Master Document

Subiculum

2012-08-31T12:50:00.001-07:00

Only primates have temporal lobes, which are largest in man, accommodating 17% of the cerebral cortex and including areas with auditory, olfactory, vestibular, visual and linguistic functions. Association fibres connect all parts of the cerebral cortex with the parahippocampal gyrus and subiculum, which in turn project to the dentate gyrus. The largest efferent projection of the subiculum and hippocampus is through the fornix to the hypothalamus. http://www.ncbi.nlm.nih.gov/pubmed/22934160

Whole-brain voxel based morphometric analysis found that higher total Lifetime Experiences Questionnaire scores are linked with increased grey matter volume in the medial temporal lobe, especially in the hippocampus. Through a series of more specific analyses, we found that supervisory and managerial experience in midlife was the dominant contributor to this effect. The rate of hippocampal atrophy in late-life in those with high level supervisory experience in midlife was five-times slower than those with no midlife supervisory experience. For the first time, we reveal that managerial and supervisory experience during our working life is connected to hippocampal integrity after retirement, some 20-30 years later. http://www.ncbi.nlm.nih.gov/pubmed/22902920

The medial temporal lobe includes a system of anatomically related structures that are essential for declarative memory (conscious memory for facts and events). http://www.ncbi.nlm.nih.gov/pubmed/15217334

The presubiculum, but not parasubiculum, was strongly reactive for glycogen phosphorylase. These patterns confirm earlier evidence that glycogenolytic demand in Layers I and III of rat entorhinal cortex is organized in a modular fashion and show that such demand can be modified by brief exposure to a novel holeboard. http://www.ncbi.nlm.nih.gov/pubmed/16229987

The anterior thalamic nuclei consist of the anterodorsal (AD), anteroventral, and anteromedial nuclei, each of which are highly differentiated and may contribute to different aspects of various cognitive and memory functions. The data show that the AD provides strong projections to layers I and IV of area 30 and to layers I, III, IV, and VI of area 29 in the retrosplenial cortex, and to layers I and III-VI of the presubiculum. The projections to the presubiculum are not organized topographically. Other minor projections were also observed in the parasubiculum and part of the medial entorhinal area. These results indicate that the AD provides strong projections to the retrosplenial cortex and presubiculum, suggesting that these projections constitute essential pathways to these cortical regions for transmitting mnemonic information, such as a novel conditioning stimulus during the initial stage of avoidance learning. http://www.ncbi.nlm.nih.gov/pubmed/22314639

These findings indicate selective early involvement of the CA1 and subiculum regions of the hippocampus and provide new information on early anterior pole involvement in the entorhinal cortex in incipient AD. http://www.ncbi.nlm.nih.gov/pubmed/22289801

The dorsal presubiculum (also known as the postsubiculum) is critically important for the direct transfer of visual landmark information to spatial signals within the limbic system. http://www.ncbi.nlm.nih.gov/pubmed/21982585

Interestingly, maltreatment was associated with 4.2% and 4.3% reductions in the left presubiculum and subiculum, respectively. http://www.ncbi.nlm.nih.gov/pubmed/22331913

The medial temporal lobe (MTL) encompasses a network of interconnected cortical areas that is considered the neural substrate for some types of memory, such as spatial, episodic, recognition, and associative memory. Within the MTL, the subiculum has been well characterized in terms of its connectivity and structure. However, the dorsal subiculum (DS) is also reciprocally connected to the perirhinal and postrhinal cortices, which are critically involved in recognition memory. This connectivity pattern suggests that DS might encode not only spatial signals but also recognition signals. Theta power was significantly higher in DS when mice explored novel objects as compared to familiar objects and that this theta modulation was absent in CA1. We also detected DS units that were responsive specifically to novel object exploration, indicating that a subset of DS neurons were tuned to novelty during the NOR task. http://www.ncbi.nlm.nih.gov/pubmed/22833721

Synaptic glutamate signaling in brain is highly complex and includes multiple interacting receptors, modulating cotransmitters and distinct regional dynamics. Hippocampal imaging studies in schizophrenia have identified 2 alterations in MTL - increases in baseline blood perfusion and decreases in task-related activation. These observations along with converging postsynaptic hippocampal protein changes suggest that homeostatic plasticity mechanisms might be altered in schizophrenia hippocampus. If hippocampal pattern separation is diminished due to partial dentate gyrus failure (resulting in "spurious associations") and also if pattern completion is accelerated and increasingly inaccurate due to increased CA3 associational activity, then it is conceivable that associations could be false and, especially if driven by anxiety or stress, could generate psychotic content, with the mistaken associations being laid down in memory, despite their psychotic content, especially delusions and thought disorder. http://www.ncbi.nlm.nih.gov/pubmed/22532703

ERPs were recorded in epilepsy patients from multicontact depth electrodes, implanted along the longitudinal axis of MTL. Patients had to respond to rare visual target stimuli by a button press. Target detection resulted in large MTL-P300 potentials in the hippocampus and subiculum. Their latencies did not differ. The hippocampal P300 amplitude increased linearly from anterior to posterior hippocampal body (HB). In contrast, an inverse gradient with larger mean amplitudes in anterior parts was observed for the subiculum. Our results indicate two separate generators of the MTL-P300, one in the anterior subiculum and one in the posterior HB. Since latencies did not differ, a parallel activation via the entorhinal cortex might have initiated the simultaneous MTL-P300. Hippocampus and subiculum are essential parts of the MTL-memory system. Their function within target detection might be to maintain a template of previous stimuli for a comparison with incoming sensory stimuli. http://www.ncbi.nlm.nih.gov/pubmed/19437422

The firing pattern of the ensemble of MTL neurons showed robust temporal autocorrelation over macroscopic periods of time during performance of the memory task. The gradually-changing part of the ensemble state was causally affected by the visual stimulus being presented. Critically, repetition of a stimulus caused the ensemble to elicit a pattern of activity that resembled the pattern of activity present before the initial presentation of the stimulus. These findings confirm a direct prediction of this class of temporal context models and may be a signature of the mechanism that underlies the experience of episodic memory as mental time travel. http://www.ncbi.nlm.nih.gov/pubmed/22488671

Objective perceptual identity correlated with activity in the left MTL, while subjective memory experience correlated with activity in the right MTL for both types of material. http://www.ncbi.nlm.nih.gov/pubmed/22230115

When a subject judged the word as "old," a second judgment was made concerning the physical similarity of the two pictures. Repetition related changes in MTL activation varied depending on whether or not subjects could correctly state that pictures were different. Moreover, psychophysiological interactions analyses showed that accuracy in recalling whether the two pictures were different was predicted by repetition-related changes in the functional connectivity of MTL with frontal regions. Specifically, correct recollection was predicted by increased connectivity between the left posterior hippocampus and the right inferior frontal gyrus, and also by decreased connectivity between the left posterior hippocampus and the left precentral gyrus on the second stimulus presentation. http://www.ncbi.nlm.nih.gov/pubmed/22807169

The role of the subiculum within the behavioural inhibition system. It receives information about available goals from areas that plan motor action. This is filtered by earlier elements of the essentially unidirectional hippocampal circuit that essentially block familiar and unimportant information while passing to the subiculum important information. The function of the subiculum is to compare and integrate this goal information and produce output when conflict between incompatible goals is detected. This output prevents execution of the responses that would address the conflicting goals, increases the valence of affectively negative stimuli and associations and releases external exploration and internal rumination intended to resolve the conflict. These subicular outputs are held to be computationally simple but to have complex consequences both because of the complexity of the target areas and because, in many cases, processing is recursive. It can involve multiple passages of essentially the same information round loops such as the circuit of Papez--each pass refining the solution to the original problem of conflicting goals. http://www.ncbi.nlm.nih.gov/pubmed/16887202

The most prominent cortical projections from the dorsal CA1 and the dorsal parts of the subicular complex are to the retrosplenial and anterior cingulated cortices in rats and monkeys — two cortical regions involved primarily in the cognitive processing of visuospatial information and memory processing and environmental exploration (spatial navigation) in rats, monkeys, and humans. Meanwhile, the dorsal (but not ventral) parts of this subicular complex send massive parallel projections through the postcommissural fornix to the medial and lateral mammillary nuclei and the anterior thalamic complex — two structures containing the most navigation-related neurons . In turn, these subcortical structures send their projections back to the DH and retrosplennial cortex . It is apparent that this neural network, composed of the dorsal CA1-dorsal subicular complex-mammillary body—anterior thalamic nuclei, provides the most important interface to register a cognitive map for the navigation/direction system, thus, enabling animals to properly orient and execute behaviors in a learned environment. Additionally, the dorsal CA1 and dorsal CA3 project rather selectively to the caudal part (LSc) and tiny dorsal region of the medial zone of the rostral part (LSr.m.d) of the lateral septal nucleus, which in turn projects to the medial septal complex and supramammillary nucleus — two structures that generate and control the hippocampal theta rhythm activated during voluntary locomotion. Furthermore, the dorsal subiculum and lateral band of the lateral and medial entorhinal cortex send massive projections to the rostrolateral part of the nucleus accumbens and rostral caudoputamen, both of which send descending projections either directly, or indirectly via the substantia innominata (ventral pallidum) or globus pallidus (dorsal pallidum), to innervate the ventral tegmental area and/or reticular part of the substantial nigra (SNr). The ventral tegmental area plays a critical role in locomotion, while the SNr mediates in orienting movements of the eyes, head, neck and even upper limbs, via its massive projection to the deeper layers of the superior colliculus. Additionally, the ventral CA1/subiculum and these amygdalar nuclei also share intimate bi-directional connectivity with the infralimbic, prelimbic and agranular insular cortices. These ventral hippocampal/subicular-amygdalar-medial prefrontal cortical structures form a series of parallel, segregated descending projections, either directly or indirectly through the lateral septum (rostral and ventral parts), the medial and central amygdalar nuclei, and bed nuclei of the stria terminalis (BST), to innervate the periventricular and medial zones of the hypothalamus — the primary structure involved in the control of neuroendocrine, autonomic, and somatic motor activities associated with three basic classes of motivated behaviors having strong emotional components: ingestion (feeding and drinking), reproduction (sexual and parental), and defense. It is worth noting that the ventral CA1, along with the ventral subiculum and medial band of the lateral and medial entorhinal cortical areas, also gives rise to direct projections to the caudomedial (shell) nucleus accumbens (but not the rostral and lateral parts), which plays a critical role in reward processing and motivation of feeding behavior. Finally, axonal terminals of the ventral CA1 and ventral subiculum overlap with the circadian-rhythm related inputs from the suprachiasmatic nucleus of the hypothalamic subparaventricular zone and dorsomedial hypothalamic nucleus — two brain structures recently shown to control the sleep-wake circadian circle. The latter two structures may provide a critical interface for the hippocampal inputs to influence general behavioral states and affect. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2822727/

The impairing effects of chronic WIN on short-term memory in the water maze and the object recognition tasks as well as long-term potentiation (LTP) in the ventral subiculum (vSub)-nucleus accumbens (NAc) pathway were temporary as they lasted only 24 h or 10 d after withdrawal. http://www.ncbi.nlm.nih.gov/pubmed/22348124

In the aversive contextual fear task, WIN into the basolateral amygdala impaired fear acquisition/consolidation, but not retrieval. In the ventral subiculum (vSub), WIN impaired fear retrieval. In the neutral social discrimination task, WIN into the vSub impaired both acquisition/consolidation and retrieval, whereas in the medial amygdala WIN impaired acquisition. http://www.ncbi.nlm.nih.gov/pubmed/21447623

In adults, TRPC4 expression was high throughout the frontal cortex, lateral septum (LS), pyramidal cell layer of the hippocampus (HIP), dentate gyrus (DG), and ventral subiculum (vSUB). Patch-clamp recording indicated a strong metabotropic glutamate-activated cation current-mediated depolarization that was dependent on intracellular Ca(2+)and inhibited by protein kinase C in brain regions associated with dense TRPC4. http://www.ncbi.nlm.nih.gov/pubmed/17593972

Cells that moderately express alpha2 mRNA were localized to the cerebral cortex layers V and VI, the subiculum, the oriens layer of CA1, the medial septum, the diagonal band complex, the substantia innominata, and the amygdala of both animals. http://www.ncbi.nlm.nih.gov/pubmed/16255031

Small islands of alpha7 immunoreactive cells were present in the outer presubiculum. alpha4 and beta2, and alpha3, alpha4 and beta2 immunoreactive fibre tracts were present in the stratum radiatum and subiculum, respectively, suggesting nAChRs may play a role in modulating inputs to the hippocampus via Schaffer collaterals and along the perforant pathway. Some astrocytes were immunoreactive for alpha3, alpha7 and beta4 subunits. Immunoreactivity to all subunits was noted in association with blood vessels. http://www.ncbi.nlm.nih.gov/pubmed/12663058

When the area of myelination was expressed relative to brain weight, there was a twofold increase between the first and second decades. The increased staining of myelin during the first and second decades principally occurred in the subicular region and adjacent portions of the presubiculum. http://www.ncbi.nlm.nih.gov/pubmed/8192550

We observed a reduction in the numerical density of parvalbumin- and somatostatin-positive interneurons in the caudal EC and parasubiculum in BPD-I and SZ, but no change in the subiculum. http://www.ncbi.nlm.nih.gov/pubmed/21968533

We found that thickness in the entorhinal (ERC) and subicular (Sub) cortices of mild cognitive impairment subjects at initial assessment correlated to change in memory encoding over two years in early stages of neurodegeneration in AD. http://www.ncbi.nlm.nih.gov/pubmed/21559183

We demonstrate that genetic deletion of the beta-secretase (BACE1) not only abrogates Abeta generation and blocks amyloid deposition but also prevents neuron loss found in the cerebral cortex and subiculum, brain regions manifesting the most severe amyloidosis. http://www.ncbi.nlm.nih.gov/pubmed/17258906

The left hippocampal volume was significantly smaller in e4-carriers than non-carriers, the effect of APOE4 mapping to the subicular/CA1 region. http://www.ncbi.nlm.nih.gov/pubmed/21224004

Our primary thesis is that the encoding of short-term memories into new, long-term memories represents the collective set of nonlinearities induced by the three or four principal subsystems of the hippocampus, i.e., entorhinal cortex-to-dentate gyrus, dentate gyrus-to-CA3 pyramidal cell region, CA3-to-CA1 pyramidal cell region, and CA1-to-subicular cortex. http://www.ncbi.nlm.nih.gov/pubmed/20700470

Higher visual medial temporal atrophy rating scale scores were associated with progressive atrophy of the subiculum and the CA1-3 subregions. http://www.ncbi.nlm.nih.gov/pubmed/20143386

A local map of the animal's surroundings is stored in CA1 and subicular regions, where matching of fragment positions and attributes takes place. http://www.ncbi.nlm.nih.gov/pubmed/1308181

The present results highlight the susceptibility of subicular plasticity to acute stress and provide evidence that GR activation is necessary but not sufficient for mediating these alterations. http://www.ncbi.nlm.nih.gov/pubmed/22918985

Spatial information outflow from the hippocampal circuit: distributed spatial coding and phase precession in the subiculum. Remarkably, despite the disparate firing rate properties of subicular neurons, we found that neurons at all proximal-distal locations exhibit robust theta phase precession, with similar spiking oscillation frequencies as neurons in area CA1. http://www.ncbi.nlm.nih.gov/pubmed/22915100

Subjects with amnestic mild cognitive impairment exhibited significant hippocampal volume reductions in the presubiculum, subiculum and cornu ammonis 2-3 areas compared with healthy subjects. http://www.ncbi.nlm.nih.gov/pubmed/22759884

According to their spiking pattern, pyramidal cells in the subiculum were classified as bursting cells and non-bursting cells. In the present study, we demonstrate that subicular bursting cells show input-specific forms of long-term potentiation (LTP). At CA1-Sub synapses, bursting cells have been shown to express a presynaptic NMDA receptor-dependent LTP that depends on the activation of a cAMP-PKA cascade (Wozny et al., Journal of Physiology 2008). In contrast, at EC-Sub synapses the induction of LTP in bursting cells shows a high induction-threshold and relies on the activation of postsynaptic NMDA receptors, postsynaptic depolarization and postsynaptic Ca(2+) influx. Each form of LTP is input-specific and fails to induce heterosynaptic plasticity. http://www.ncbi.nlm.nih.gov/pubmed/22104348

Here we show using a complete rat hippocampal preparation in vitro that the subiculum intrinsically and independently generates spontaneous slow (25-50 Hz) and fast (100-150 Hz) gamma rhythms during the rising phase and peak of persistent subicular theta rhythms. These two gamma frequencies are phase modulated by theta rhythms without any form of afferent input from the entorhinal cortex or CA1. Fast GABAergic inhibition is required for the generation of fast gamma, whereas slow gamma is generated by excitatory and inhibitory mechanisms. In addition, the transverse subicular axis exhibits gamma rhythm topography with faster gamma coupling arising in the distal subiculum region. These results suggest the subiculum is a third spontaneous gamma generator in the hippocampal formation (in addition to CA3 and the entorhinal cortex). http://www.ncbi.nlm.nih.gov/pubmed/21865453

We used single and paired intracellular patch clamp recordings from post-hoc-identified cells in acute rat hippocampal slices and identified a subpopulation of molecular layer interneurons that expressed immunocytochemical markers present in members of the neurogliaform cell (NGFC) class. Single NGFCs displayed small dendritic trees, and their characteristically dense axonal arborizations covered significant portions of the outer and middle one-thirds of the molecular layer, with frequent axonal projections across the fissure into the CA1 and subicular regions. http://www.ncbi.nlm.nih.gov/pubmed/21452204

Ventral subicular lesioning impaired the spatial task performances in rats and produced considerable degree of dendritic atrophy of the hippocampal pyramidal neuron. http://www.ncbi.nlm.nih.gov/pubmed/21074573

Using high-resolution fMRI (1.6 mm × 1.6-mm in-plane), we found that activity within the right CA23DG increased during encoding compared to retrieval. Conversely, right subicular activity increased during retrieval compared to encoding of spatial associations. http://www.ncbi.nlm.nih.gov/pubmed/20882543

Apoptotic neurons were detected in the subicular region of both suicide and Addison victims, and it is statistically significant in both right and left between the cases. The present study confirms the vulnerability of the subicular neurons to apoptosis, possibly due to corticosteroids in both ends of spectrum. http://www.ncbi.nlm.nih.gov/pubmed/20048453

In contrast to CA1 pyramidal cells, bursting pyramidal cells in the subiculum showed a Na(+) spike-evoked medium afterhyperpolarizations that was reduced by apamin, indicating cell-type-dependent differences in mAHP mechanisms. http://www.ncbi.nlm.nih.gov/pubmed/18684909

With antibodies raised against the N-terminal mouse EAAT4 sequence, the highest protein expression levels were observed in the substantia nigra pars compacta, ventral tegmental area, paranigral nucleus, habenulo-interpeduncular system, supraoptic nucleus, lateral posterior thalamic nucleus, subiculum, and superficial layers of the superior colliculus. http://www.ncbi.nlm.nih.gov/pubmed/18770868

Ventral subiculum (vSUB) lesions enhance corticosterone responses to psychogenic stressors via trans-synaptic influences on paraventricular nucleus (PVN) neurons. Synaptic relays likely occur in GABA-rich regions interconnecting the vSUB and PVN. Exposure to novelty stress increased c-fos mRNA expression in the PVN to a greater degree in vSUB lesion relative to shams, consistent with an inhibitory role for the vSUB in the HPA stress response. vSUB lesions increased GAD65 or GAD67 mRNA levels in several efferent targets, including anterior and posterior subnuclei of the bed nucleus of the stria terminalis and lateral septum. Lesions did not effect stress-induced increases in GAD65 expression in principal output nuclei of the amygdala. The current data suggest that loss of vSUB innervations produces a compensatory increase in GAD expression in subcortical targets; however, this up-regulation is insufficient to block lesion-induced stress hyperresponsiveness, perhaps driven by amygdalar disinhibition of the PVN. http://www.ncbi.nlm.nih.gov/pubmed/16979601

The ventral subiculum (vSUB) is an interface between the hippocampal formation and structures in the brain reward circuitry, such as the nucleus accumbens (NAc) and prefrontal cortex (PFC). The vSUB powerfully activates the dopamine system, particularly in response to novelty. This activity is both necessary and sufficient to elevate nucleus accumbens dopamine levels triggered by a novel stimulus. Direct stimulation of the vSUB increases the population of active dopamine neurons in the ventral tegmental area and dopamine levels in the accumbens via a multisynaptic route relayed through the nucleus accumbens. Furthermore, activity in the vSUB is correlated with drug-seeking behaviour such that vSUB inhibition attenuates cocaine-primed reinstatement of drug-seeking, while brief vSUB activation triggers reinstatement cocaine-seeking. We report that acute cocaine alters vSUB pyramidal neuron activity by inducing a frequency-dependent output mode transition from bursting to single-spiking. We suggest that under normal conditions bursting and output mode switching (bursting to single-spiking) may be needed for proper routing of information in and out of the vSUB. We propose that psychostimulants disrupt bursting and output mode switching leading to inappropriate dopamine/novelty signaling that is necessary to set motivational states and direct attention and ultimately, behaviour. http://www.ncbi.nlm.nih.gov/pubmed/16870273

Increased excitability enhances the flow of hippocampal output through the subiculum resulting in support for frontal lobe function and the action mode. Decreased excitability, on the other hand, reduces this output and that support, leading to a disconnection between frontal lobes and hippocampus. At the same time, correlated cholinergic activity enhances receptive mode processes, indicated by the occurrence of the hippocampal theta rhythm. It is suggested that the hypothesis provides a conceptual framework for considering various phenomena including REM sleep, schizophrenia, and hypnosis. In REM sleep the receptive mode remains dominant as cholinergic activity supports the hippocampal integration of experience into a composite view of reality. In schizophrenia, the action and receptive modes are not properly coordinated because of a dysfunction in anterior hippocampal output. http://www.ncbi.nlm.nih.gov/pubmed/16824701

In addition, inactivating the vSub with TTX attenuates the ability of the BLA to drive spike firing in the NAc. Thus, the vSub is required for activation of the NAc by the BLA. http://www.ncbi.nlm.nih.gov/pubmed/21211108

The ventral subiculum (vSUB), a hippocampal efferent target implicated in learning and stress coping, receives cholinergic input and sends glutamatergic output to the bed nucleus of the stria terminalis (BNST). Results of the 1-day retention tests showed that intra-vSUB infusion of oxotremorine (0.01 microg) or scopolamine (0.3 or 3.0 microg) enhanced or impaired retention, respectively. These data suggest that in an inhibitory avoidance task muscarinic activation of the vSUB modulated memory formation by interacting with the BNST glutamatergic and noradrenergic functions. http://www.ncbi.nlm.nih.gov/pubmed/19041726

The ventral subiculum (vSub) of the hippocampus, in particular, is proposed to gate information flow within the NAc, a factor that is disrupted in models of schizophrenia. Using in vivo extracellular recordings in anesthetized rats, we examined the response of NAc neurons to vSub stimulation and how this is modulated by the mPFC. We found that inactivation of mPFC by tetrodotoxin attenuates the ability of the vSub to drive spike firing in the NAc. Thus, a contribution of the mPFC is required for the activation of NAc by the vSub. However, when long-term potentiation is induced in the vSub-NAc pathway, the vSub is now capable of driving the NAc without the participation of the mPFC. Moreover, this interaction is dependent on activation of dopaminergic D(2) receptors in the NAc. This work demonstrates the critical role of the mPFC in the ability of vSub to drive NAc neurons in normal anesthetized animals. One model of schizophrenia posits that vSub hyperactivity may underlie both the hyperdopaminergic state and disruption of information flow in this circuit in schizophrenia. Therefore, inactivation of the mPFC, as would occur with mPFC leukotomy in schizophrenia, may prevent the abnormal vSub drive of the NAc. http://www.ncbi.nlm.nih.gov/pubmed/18815264

D1 receptor antagonism (3.0 nmol/0.5 microl SCH-23390 bilaterally) in the vSUB impaired instrumental learning and performance, reduced break point in progressive ratio (PR) tests, and produced an intrasession decline in responding during test sessions, but had no effect on spontaneous motor or food-directed behavior. D1 activation in the vSUB may be a critical component of motivational arousal associated with learned contextual cues. http://www.ncbi.nlm.nih.gov/pubmed/16768606

In the hippocampal formation (dentate gyrus, hippocampus proper and subiculum) and entorhinal cortex, the colocalization of the 5-HT2Ar with the inhibitory transmitter ?-aminobutyric acid (GABA) was studied using double immunofluorescence confocal microscopy. http://www.ncbi.nlm.nih.gov/pubmed/22119732

Subjects with late life depression exhibited significant hippocampal volume reductions in the total hippocampus, subiculum, and Cornu Ammonis (CA) 2-3 areas compared with healthy subjects. http://www.ncbi.nlm.nih.gov/pubmed/22840623

In hippocampal formation of control subjects, H3 receptor radioligand binding was prominent in dentate gyrus, subiculum, entorhinal cortex and parasubiculum. Decreased H3 binding was found in the CA4 area of bipolar subjects. Decreased H3 binding in CA2 and presubiculum of medication-free bipolar subjects was also seen. http://www.ncbi.nlm.nih.gov/pubmed/19413576

High levels of GalR2 mRNA and protein expression were observed in the presubiculum, subiculum, cingulate cortex, retrosplenial granular and agranular cortices, subregions of prefrontal cortex, and the olfactory bulb, regions which are directly or indirectly implicated in depression-like behavior. http://www.ncbi.nlm.nih.gov/pubmed/21672612

SNAP-25 levels were reduced significantly in stratum oriens of bipolar patients compared with controls (p < 0.05); they were also reduced significantly in st. oriens (p < 0.01 vs schizophrenia), in alveous (p < 0.01 vs schizophrenia) and in presubiculum (p < 0.05 vs depressed). Depressed SNAP-25 levels increased in st. moleculare (p < 0.01 vs schizophrenics) and presubiculum (p < 0.05 vs controls and bipolars; p < 0.01 vs schizophrenics). http://www.ncbi.nlm.nih.gov/pubmed/11711867

The findings also suggest further functional differences within retrosplenial subregions as area 29 received the large majority of efferents from the subiculum. http://www.ncbi.nlm.nih.gov/pubmed/22522494

Somatostatin messenger RNA (mRNA) is rapidly but transiently expressed de novo in pyramidal neurons of the subiculum and entorhinal cortex 24 hours after KA. Surviving somatostatin interneurons display increased mRNA levels at late intervals (3 months) after KA and increased labeling of their terminals in the outer molecular layer of the subiculum; the labeling correlates with the number of spontaneous seizures, suggesting that the seizures may trigger somatostatin expression. In contrast, neuropeptide Y mRNA is consistently expressed in principal neurons of the proximal subiculum and the lateral entorhinal cortex and labeling for the peptide persistently increased in virtually all major excitatory pathways of the hippocampal formation. The pronounced plastic changes differentially involving both neuropeptide systems indicate marked rearrangement of parahippocampal areas, presumably aiming at endogenous seizure protection. http://www.ncbi.nlm.nih.gov/pubmed/22437342

We conclude that the deep layer cells of the presubiculum and parasubiculum are richly interconnected with excitatory synapses. These interconnections can generate giant excitatory synaptic potentials that support the bursting behaviour exhibited by these neurons. Any of the excitatory inputs to deep layer cells can trigger the population bursts and specific inputs from entorhinal cortex produce the after-discharges. http://www.ncbi.nlm.nih.gov/pubmed/9192310

We found that subicular projections to each area were composed of a mixture of regular-spiking and bursting neurons. Neurons projecting to amygdala, lateral entorhinal cortex, nucleus accumbens, and medial/ventral orbitofrontal cortex were located primarily in the proximal subiculum and consisted mostly of regular-spiking neurons (~80%). By contrast, neurons projecting to medial EC, presubiculum, retrosplenial cortex, and ventromedial hypothalamus were located primarily in the distal subiculum and consisted mostly of bursting neurons (~80%). Neurons projecting to a thalamic nucleus were located in the middle portion of subiculum, and their probability of bursting was close to 50%. http://www.ncbi.nlm.nih.gov/pubmed/21538658

This, possibly novel, TTX-I sodium current could contribute to the coding functions of presubicular neurons, specifically the maintained firing associated with signalling of a stable head position. http://www.ncbi.nlm.nih.gov/pubmed/19596892

Saturation binding and displacement experiments showed that [(125)I]YVP and [(125)I]EYF bound selectively with a very high affinity, K(D)=0.18 nM and 0.06 nM, to NPFF(1) and NPFF(2) receptors respectively.The highest densities of [(125)I]EYF binding sites were seen in the most external layers of the dorsal horn of the spinal cord, the parafascicular thalamic nucleus, laterodorsal thalamic nucleus and presubiculum of hippocampus. http://www.ncbi.nlm.nih.gov/pubmed/12421602

Vesicular glutamate transporter 1 (VGluT1) is one of the best markers for glutamatergic neurons, because it accumulates transmitter glutamate into synaptic vesicles. Differentiation-associated Na(+)-dependent inorganic phosphate cotransporter (DNPI) shows 82% amino acid identity to VGluT1, and is another candidate for vesicular glutamate transporters. Both DNPI and VGluT1 immunoreactivities were found mostly in neuropil, presumably in axon terminals, throughout the brain. In the telencephalic regions, intense DNPI immunoreactivity was observed in the glomeruli of the olfactory bulb, layer IV of the neocortex, granular layer of the dentate gyrus, presubiculum, and postsubiculum. In contrast, VGluT1 immunoreactivity was intense in the olfactory tubercle, layers I-III of the neocortex, piriform cortex, entorhinal cortex, hippocampus, dentate gyrus, and subiculum. http://www.ncbi.nlm.nih.gov/pubmed/11835181

The regions of highest V1a receptor density included the prefrontal, cingulate, pyriform, and entorhinal cortex, as well as the presubiculum and mamillary bodies. http://www.ncbi.nlm.nih.gov/pubmed/10223283

The parasubiculum and the external principal lamina of the presubiculum may be the structures most vulnerable to early lesions in the parahippocampal gyrus in CJD. http://www.ncbi.nlm.nih.gov/pubmed/9988133

Social Fodder

2012-06-14T18:41:00.001-07:00

As we get more toxic from industrial body burdens compounding psychological stress, this harm prevention networking becomes impossible, or improbable without the youth like us, resilient to the damages enough to be competent to the causes. The chance for community rejuvenation lies in the youth, specifically the youth predisposed to store less toxins from having less genes to store fat. The social qualities of these individuals will be a critical precursor. If we ever manage anything beyond personal gain or moral support, it will have to be a corporate involvement with home infrastructure to reduce reliance on all but the community. Every home built with independence. Producing your own fuel. Indoor green-housing can be tailored into the construct of the houses (rain capturing, angles of sunlight, rooms designated for filtration). One family growing sprouts and nuts can barely support one family for cell protection and locomotion if at all. Everyone together can scale the size up to account for one another through labor and barter. Step 1. Socialize the concepts into existence. Step 2. Implement the infrastructure from businesses. Step 3. Amplify efficiency to a state of permanent unity. Address body burdens by condition; predictable causes targeted with predictable solutions, prioritized for extent of care. Old people are not naturally useless, and can be brought back for the sake of the young. Youth should receive as much attention as we do, but not the way it is now. It may be a pipe dream to bring capitalist precedence to it's knees, but it would sure prevent unnecessary arguments. It's not as if 'our' culture is so unique that it has to willfully ignore health care from other cultures. Big Pharma and Big Agro are banking on their zombie masses being separate in will and information so thoroughly to complacently accept oppression. The oppression is excused as latent or necessary; whereas it is an active and cruel project to turn consumerist fodder into useful coroners reports.

Synopsis

2012-05-13T09:57:00.001-07:00

Subsequent Responses And Toward And Untoward Error Perception From Other's Perspectives On A Synopsis Of Modern Human: societal phylogenetics for consumer goods, resisting tire at night and relationship to chronoastrobiology of self-organized and group-organized experimental glycolipid phylogenetic biophysics and the mind-mitochondrial-gonad axes and it's relationship to predicted random walk based on methylation status of conserved brain genes and copy number variants and the correlation with interactive waves and particles and their intensities, electronics and industrial pollutants in consumer goods, hinging on time spent in atmospheric particle density sites and contact with the grounds of these hotspots with absorbtive cells and the biophysics of the absorbtive cells in the process, functional gains and losses, thermodynamics, reactive hemodynamics and neurology referring to cannabinoids and tao and their organizations towards neurological interactions in neural cytoarchitecture based on endogenous retroviral transcript and regional laterality shifting and the mitochondrias viral transcripts mechanistic regulation yet mutualist relation with the demanded biophysics and how the mitochondria genome adapts to this independently and its relationship to people who would be enabled to discuss such an order and event and their physics of articulation and language display and response to themselves and the known confines of human organized emotional relationship and their sequences and superimposition implications in the context, social entropy and negentropy from individual self-experience and empirical observation leading to agreement and its relationship to mitochondria, being signaled by the phosphate-related molecules similarly in the active epigenetic reprogramming events of present moments cyclic adenosine monophosphate, adenosine monophosphate kinase and relationship to fatty acid synthase, fatty acid amide hydrolase and monoacylglycerol lipase and organ integrity in biophysics of neurology and accidental, arbitrary, and pro-active sought durations of things on minds consequential to information field development, glycolipid bioelectromagnetics and consciousness of the rise of self-awareness in binary confines produced as a result of the self-perception such as good and bad in the good and bad centers of the brain dominated by the hippocampus, then brainstem for pains, language centers, and self-centers in pre-frontal densities and the ability to seek to regulate the good pro-actively in the confined parameters of capacity, and coordination with psychic and physical pain and pleasure and it's augmentation of information field development in self and others as a function of the chronoastrobiology and total system thermodynamics including glaciological and volcanological in meteorological control over food chain base abundances and qualities in regulation of the retroviral transcripts in present moments and up-chain risks in microwave food biotechnology in disorganization of horizontal gene transfer, DNA information processing capacities, and chromophores and chromatin in context to success of chromosomes and complexification of quantum chromodynamics and it's relationship to electron-phonon-photon coupling and alterations of effects on sequences of hereditary infuenced biological relationship to local geophysics, anxiety, fear, migratory phenotype, and pineal hydrodynamics at the moments the self realizes indefinitely the concerns involved and precedents and expectations for biotic and abiotic stress, terrorism, and internal tensional and intentional integrity decline and effects on seeking of variables acting as resonances for resilience.

May-OCT11

2011-10-11T17:03:00.001-07:00

BMC Gastroenterol. 2011 Feb 23;11:14.
The actin-bundling protein fascin is overexpressed in inflammatory bowel disease and may be important in tissue repair.
Qualtrough D, Smallwood K, Littlejohns D, Pignatelli M.
Source

School of Cellular and Molecular Medicine, University of Bristol, UK. david.qualtrough@bristol.ac.uk
Abstract
BACKGROUND:

Fascin is associated with increased cell motility in colorectal tumours but is absent from the normal colonic epithelium. We examined the expression of fascin in inflammatory bowel disease (IBD) and its location at regions undergoing restitution and regeneration. Tissue repair is essential for disease remission and we sought to determine the effects of therapeutic modalities on fascin expression and function using an in vitro model.
METHODS:

Immunohistochemistry was performed on colonic tissue from IBD patients to determine changes in fascin expression and distribution. A human colorectal epithelial cell line was treated with 5-aminosalicylate (a common treatment for IBD), or sodium butyrate to determine the effect on fascin expression and cell motility.
RESULTS:

Fascin overexpression was observed in both ulcerative colitis and Crohn's colitis and expression correlated with disease severity. Immunoreactivity was more intense and widespread in Crohn's compared to ulcerative colitis. Interestingly, highly expressing foci were consistently observed at the edges of ulcers where flattened, motile epithelial cells are actively involved in restitution, and also in areas of mucosal regeneration.5-aminosalicylate reduced fascin expression in colorectal epithelial cells and inhibited their motility. Conversely, sodium butyrate increased fascin expression and stimulated cell motility in the same cells.
CONCLUSIONS:

Our data shows that fascin is overexpressed in inflammatory bowel disease and its location is indicative of a role in tissue repair. Our in vitro studies show that different therapeutic modalities may have converse effects on fascin expression and may have significant consequences for disease remission and the clinical management of IBD.

PMID:
    21345224

Dig Dis Sci. 2000 May;45(5):976-81.
Combined oral sodium butyrate and mesalazine treatment compared to oral mesalazine alone in ulcerative colitis: randomized, double-blind, placebo-controlled pilot study.
Vernia P, Monteleone G, Grandinetti G, Villotti G, Di Giulio E, Frieri G, Marcheggiano A, Pallone F, Caprilli R, Torsoli A.
Source

Cattedra di Gastroenterologia 1, Università La Sapienza, Roma, Italy.
Abstract

Butyrate represents the main source of energy for colonic epithelial cells; however, its availability/utilization is impaired in ulcerative colitis (UC). In the present randomized, double-blind, placebo-controlled pilot study, the safety and efficacy of colonic targeted oral sodium butyrate tablets, coated with a pH-dependent soluble polymer, have been evaluated in ulcerative colitis. Thirty patients with mild to moderate colitis underwent a six-week course of oral sodium butyrate (4 g/day) plus oral mesalazine (2.4 g/day), (Group A) or of oral mesalazine plus placebo (Group B). Clinical, endoscopic, and histologic data were collected at the beginning and the end of the study. Twenty-five patients completed the study (12 in group A, 13 in group B). No untoward side effects were reported. In group A, seven patients underwent remission and four improved; in Group B the numbers were 5 and 5, respectively. After treatment, all clinical parameters had significantly improved in both treatment arms compared to pretreatment findings. The UC disease activity index (UCDAI) score decreased from 7.27 +/- 2.02 to 2.58 +/- 2.19 (P < 0.05) in the combined treatment group and from 6.07 +/-1.60 to 3.46 +/- 1.98 (P < 0.05) in group B. The endoscopic and histologic scores also significantly improved after treatment in both groups (P < 0.05). The difference between the two treatment arms was not significant, but a significantly better improvement vs baseline values (P < 0.05) was observed in the combined treatment group vs the mesalazine group, when considering both the clinical index (delta9.58 +/- 4.19 vs 5.92 +/- 3.48) and the UCDAI score (delta4.67 +/- 2.19 vs 2.54 +/- 2.18). A more favorable trend, although not significant, was observed for all individual parameters in group A. In conclusion, results of the present pilot study indicate that oral butyrate is safe and well tolerated. These data also suggest that oral butyrate may improve the efficacy of oral mesalazine in active ulcerative colitis and prompt the need of a large scale investigation to confirm the present findings.

PMID:
    10795763

Cancer Lett. 2000 Sep 29;158(1):61-4.
Serum alpha-N-acetylgalactosaminidase is associated with diagnosis/prognosis of patients with squamous cell carcinoma of the uterine cervix.
Reddi AL, Sankaranarayanan K, Arulraj HS, Devaraj N, Devaraj H.
Source

Unit of Biochemistry, Department of Zoology, University of Madras, Guindy Campus, 600 025, Chennai, India. vkmalr@hotmail.com
Abstract

Serum alpha-N-acetylgalactosaminidase (NaGalase) is responsible for the deglycosylation of vitamin D(3)-binding protein (Gc protein). The deglycosylated Gc protein cannot be converted into major macrophage-activating factor (MAF), leading to immunosuppression. NaGalase is universally detected in a variety of cancer patients, but not in healthy individuals (Cancer Res. 56 (1997) 2827-2831). However, the diagnostic/prognostic utility of NaGalase in squamous cell carcinoma (SCC) of the uterine cervix is not known. To address this issue, the serum NaGalase was quantitatively determined in 210 patients with different stages of SCC of the uterine cervix. NaGalase levels were increased with the progression of the cancer. After radiotherapy, the increased levels returned toward or to normal levels in early stages (FIGO stage I-IIB) but not in advanced stages (FIGO stage III-IV). The present study revealed that the amount of NaGalase in the patient's bloodstream reflects the tumor burden and aggressiveness of the disease. We conclude that NaGalase is an independent predictor of diagnosis/prognosis in SCC of the uterine cervix, and therefore suggest that quantitative NaGalase alteration may reflect important differences in the immunological functions of these neoplasms.

PMID:
    10940510

Proc Biol Sci. 2010 Feb 7;277(1680):345-51. Epub 2009 Oct 21.
Reelin and apolipoprotein E receptor 2 in the embryonic and mature brain: effects of an evolutionary change in the apoER2 gene.
Myant NB.
Source

MRC Clinical Sciences Centre, Imperial College London, Hammersmith Hospital, , London W12 0NN, UK. audreymyant@hotmail.com
Abstract

In the mature cerebral cortex of higher vertebrates, neurons are arranged in layers, each layer containing neurons of the same functional class. The cortical layering pattern is laid down during development by migration of young post-mitotic neurons along glial fibres to their correct positions in the cortical plate. The mechanics of whole-cell movement are well understood, but there is still uncertainty as to how a migrating neuron is instructed to leave its glial support when it reaches its destination. An intraneuronal signalling pathway initiated by reelin and containing apolipoprotein E receptor 2 (apoER2) is essential for normal cortical layering, and there is strong evidence that detachment of a migrating neuron is brought about by reelin-dependent downregulation of alpha3 integrin. But there remains the problem of how the reelin signal is switched on at a position in the cortex appropriate for each class of neuron. ApoER2 of placental mammals contains an amino acid sequence that is encoded in a separate exon in the apoER2 gene and is required for normal memory and spatial learning. The separate exon is not present in marsupials, birds or reptiles. The addition of this exon to the evolving apoER2 gene may have contributed to the success of placental mammals.

PMID:
    19846452

Neuroscience. 2010 Mar 17;166(2):625-32. Epub 2009 Dec 24.
Insulin-like growth factor-1 stimulation of hypothalamic KiSS-1 gene expression is mediated by Akt: effect of alcohol.
Hiney JK, Srivastava VK, Les Dees W.
Source

Department of Integrative Biosciences, College of Veterinary Medicine, Texas A and M University College Station, TX 77843-4458, USA. jhiney@cvm.tamu.edu
Abstract

Kisspeptin, as well as insulin-like growth factor-1 (IGF-1), act centrally to stimulate luteinizing hormone-releasing hormone (LHRH) secretion at puberty. IGF-1 can induce KiSS-1 gene expression as an early pubertal event; however, the signaling pathway mediating this effect is not known. Since alcohol (ALC) blocks IGF-1 induced LHRH release acutely, we assessed whether this drug could affect IGF-1 stimulated prepubertal KiSS-1 gene expression following a binge type of exposure. Immature female rats were administered either ALC (3 g/kg) or water via gastric gavage at 07.30 h. At 09.00 h the ALC and control groups were subdivided where half received either saline or IGF-1 (200 ng) into the third ventricle. A second dose of ALC (1.5, 2 and 3 g/kg) or water was administered at 11.30 h. These regimens produced moderate blood alcohol concentrations of 77, 89 and 117 mg/dl, respectively, over the time course of the experiment. Rats were sacrificed 6 h after the IGF-1 injection and tissues containing the anteroventral periventricular (AVPV) and arcuate (ARC) nuclei were collected. IGF-1 stimulated (P<0.01) KiSS-1 gene expression in the AVPV nucleus at 6 h, but did not affect expression of the kisspeptin receptor, GPR54. While ALC did not alter basal expression of either gene, its dose dependently blocked IGF-1-induced KiSS-1 gene expression in the AVPV nucleus. No changes were observed in the ARC nucleus. Assessment of IGF-1 signaling indicated that the acute administration of IGF-1, ALC, or both did not alter the basal expression of IGF-1 receptor protein. However, IGF-1 stimulated (P<0.05) phosphorylated Akt protein over basal levels, an action blocked by ALC. Our results indicate that the IGF-1 induction of KiSS-1 gene expression is mediated by Akt activation, and that ALC alters this important prepubertal action of IGF-1.

Copyright (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

PMID:
    20034543

Int J Neuropsychopharmacol. 2011 May 4:1-11. [Epub ahead of print]
Cerebroside-A provides potent neuroprotection after cerebral ischaemia through reducing glutamate release and Ca2+ influx of NMDA receptors.
Li L, Yang R, Sun K, Bai Y, Zhang Z, Zhou L, Qi Z, Qi J, Chen L.
Source

Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China.
Abstract

Excessive presynaptic glutamate release after cerebral ischaemia leads to neuronal death mainly through excessive calcium entry of N-methyl-d-aspartate receptors (NMDARs). Our recent study reported that cerebroside can open large-conductance Ca2+-activated K+ (BKCa) channels. The present study evaluated the effects of cerebroside-A (CS-A), a single molecule isolated from an edible mushroom, on brain injury after focal or global ischaemia in adult male mice and rats. We herein report that treatment with CS-A after 60-min middle cerebral artery occlusion dose-dependently reduced the cerebral infarction with at least a 6-h efficacious time-window, which was partially blocked by the BKCa channel blocker charybdotoxin (CTX). Treatment with CS-A after 20 min global cerebral ischaemia (four-vessel occlusion) significantly attenuated the death of pyramidal cells in hippocampal CA1 area, which was also sensitive to CTX. CS-A, by opening the BKCa channel, could prevent excessive glutamate release after oxygen-glucose deprivation (OGD). In addition, CS-A could inhibit NMDAR Ca2+ influx, which did not require the activation of the BKCa channel. Furthermore, CS-A blocked the OGD-induced NMDAR-dependent long-term potentiation in hippocampal CA1 region. These findings indicate that treatment with CS-A after stroke exerts potent neuroprotection through prevention of excessive glutamate release and reduction of Ca2+ influx through NMDARs.

PMID:
    21557879

Morfologiia. 2010;137(2):38-43.
[Changes in duodenal lymphoid structures in rats with various behavioral activity, caused by delta sleep-inducing peptide and following acute emotional stress].
[Article in Russian]
Ivanova EA, Koplik EV.
Abstract

The effect of delta sleep-inducing peptide (DSIP) on the lymphoid structures of small intestine, was investigated. Studies were conducted on 42 male Wistar rats, which were previously assessed in an "open field" test. According to the results of the test, rats were divided into behaviorally active animals (prognostically resistant to stress) and passive ones (resistant to the effects of stress). As a stress, immobilization of the animals in pens with an electrical stimulation of their back for 1 hour, was used. Intraperitoneal injection of DSIP resulted in a reduction of eosinophil number in rats of all the experimental groups. After DSIP injection to the active rats of the control group, the increase in small and medium lymphocyte numbers was detected that was more expressed than in the passive rats. After an acute exposure of behaviorally active rats to stress, the number of the cells of lymphoid series was increased,mainly due to the increase in small and medium lymphocytes. In the group of passive rats, stress exposure and DSIP injection resulted in the increase of plasma cell number in all the duodenal mucosa structures studied.

PMID:
    20572393

Metallomics. 2011 May 1;3(5):513-20. Epub 2011 Feb 18.
Identification in human urine and blood of a novel selenium metabolite, Se-methylselenoneine, a potential biomarker of metabolization in mammals of the naturally occurring selenoneine, by HPLC coupled to electrospray hybrid linear ion trap-orbital ion trap MS.
Klein M, Ouerdane L, Bueno M, Pannier F.
Source

Laboratoire de Chimie Analytique Bio Inorganique et Environnement, IPREM, Université de Pau et des Pays de l'Adour / CNRS UMR 5254, Hélioparc, Avenue du Pr. Angot, Pau, France.
Abstract

Speciation analysis of selenium in human urine allowed for the first time the identification of a novel selenium metabolite, Se-methylselenoneine. Despite a concentration at low ppb level, its characterization was achieved after sample purification by solid phase extraction (SPE) followed by the parallel coupling of the bidimensional RP/HILIC chromatography with ICP-MS and ESI-LTQ Orbitrap MS detection. To confirm its biological significance with regards to selenoneine, the recently discovered analog of ergothioneine, and to discard the possibility of sample preparation artifacts, a new method was developed to monitor its actual presence, as well as the occurrence of its sulfur and/or non-methylated analogs, in non-preconcentrated urine and blood samples of non-supplemented humans. It consisted in a HILIC ESI-MS(3) method in high resolution mode (resolution 30?000 at m/z 400) with large isolation width windows for precursor ions. These two particular settings allowed respectively to keep observing the specific mass defect of selenium- and sulfur-containing molecules and to maintain the characteristic selenium pattern in product ions created through MS(n) fragmentations. As a result, all four metabolites were detected in blood and three of them in urine. Moreover, different ratios "methylated/non-methylated" were observed between urine and blood samples, which seemed to indicate their active metabolization. The analytical tool developed here will be of a great importance to further study the occurrence and the potential metabolic role in mammalian organelles, cells and fluids of these very particular and promising redox metabolites.

PMID:
    21331438

J Med Entomol. 2006 Sep;43(5):889-95.
Fumigant and repellent properties of essential oils and component compounds against permethrin-resistant Pediculus humanus capitis (Anoplura: Pediculidae) from Argentina.
Toloza AC, Zygadlo J, Cueto GM, Biurrun F, Zerba E, Picollo MI.
Source

Centro de Investigaciones en Plagas e Insecticidas (CITEFA-CONICET), Juan Bautista De La Salle 4397 (B1603ALO) Villa Martelli, Provincia de Buenos Aires, Argentina.
Abstract

The repeated use of permethrin and other insecticides for the control of head lice, Pediculus humanus capitis De Geer (Anoplura: Pediculidae), during past decades has resulted in the development of marked levels of resistance. Thus, new alternative insecticides are needed for the control of head lice. We studied the fumigant and repellent properties of essential oils from 16 native and exotic plants in Argentina, and 21 chemical components against permethrin-resistant head lice from Argentina. With a direct vapor-exposure bioassay, the most effective oil was from the native Myrcianthes cisplatensis Cambess (Myrtaceae) with a time to 50% knockdown (KT50) of 1.3 min, followed by exotic species, Eucalyptus cinerea F.V. Muell., Eucalyptus viminalis Labill., and Eucalyptus saligna Smith. with KT50 values of 12.0, 14.9, and 17.4 min, respectively. The most effective components were 1,8-cineole and anisole, with KT50 values of 11.1 and 12.7 min, respectively. Regression analysis of KT50 values and vapor pressures and water-partition coefficients for the essential oil components revealed that the most effective fumigants were among the more volatile components. Repellency assays indicated that the essential oil from Mentha pulegium L. and its benzyl alcohol component were the most effective repellents, having repellency indices of 75.5 and 57.8%, respectively. Thus, some Argentinean plants contain essential oils and components that function as fumigants or as repellents and thereby show potential for development of new control products for head lice.

PMID:
    17017225

Int J Ayurveda Res. 2010 Apr;1(2):112-21.
Tinospora cordifolia (Willd.) Hook. f. and Thoms. (Guduchi) - validation of the Ayurvedic pharmacology through experimental and clinical studies.
Upadhyay AK, Kumar K, Kumar A, Mishra HS.
Source

Department of Ayurved Research and Development, Patanjali Yogpeeth, Haridwar, India.
Abstract

T. cordifolia (Guduchi) is a large, glabrous, perennial, deciduous, climbing shrub of weak and fleshy stem found throughout India. It is a widely used plant in folk and Ayurvedic systems of medicine. The chemical constituents reported from this shrub belong to different classes, such as alkaloids, diterpenoid lactones, glycosides, steroids, sesquiterpenoid, phenolics, aliphatic compounds and polysaccharides. Various properties of T. cordifolia, described in ancient texts of Ayurveda, like Rasayana, Sangrahi, Balya, Agnideepana, Tridoshshamaka, Dahnashaka, Mehnashaka, Kasa-swasahara, Pandunashaka, Kamla-Kushta-Vataraktanashaka, Jwarhara, Krimihara, Prameha, Arshnashaka, Kricch-Hridroganashak, etc., are acquiring scientific validity through modern research adopting "reverse pharmacological" approach. Potential medicinal properties reported by scientific research include anti-diabetic, antipyretic, antispasmodic, anti-inflammatory, anti-arthritic, antioxidant, anti-allergic, anti-stress, anti-leprotic, antimalarial, hepato-protective, immuno-modulatory and anti-neoplastic activities. This review brings together various properties and medicinal uses of T. cordifolia described in Ayurveda, along with phytochemical and pharmacological reports.

PMID:
    20814526

J Altern Complement Med. 2006 Dec;12(10):971-80.
Trial of Essiac to ascertain its effect in women with breast cancer (TEA-BC).
Zick SM, Sen A, Feng Y, Green J, Olatunde S, Boon H.
Source

Integrative Medicine, University of Michigan, Ann Arbor, MI 48104-1555, USA. szick@umich.edu
Abstract
BACKGROUND:

Breast cancer is a major cause of morbidity, mortality, and medical expenditures among women in Canada. Essiac (Resperin Canada Limited, Waterloo, Ontario, Canada), a blend of at least four herbs (burdock root [Arctium lappa], Indian rhubarb [Rheum palmatum], sheep sorrel [Rumex acetosella], and the inner bark of slippery elm [Ulmus fulva or U. rubra]), has become one of the more popular herbal remedies for breast-cancer treatment, secondary prevention, improving quality of life, and controlling negative side-effects of conventional breast-cancer treatment.
OBJECTIVES:

Our primary objective was to determine the difference in health-related quality of life (HR-QOL), as assessed by the Functional Assessment of Cancer Therapy Breast Cancer Version, between women who are new Essiac users (since breast cancer diagnosis) and those who have never used Essiac. Secondary endpoints included differences in depression, anxiety, fatigue, rate of adverse events, and prevalence of complications or benefits associated with Essiac during standard breast-cancer treatment. Additionally, we described the pattern of use of Essiac in this cohort of women.
METHODS:

We performed a retrospective cohort study in 510 women, randomly chosen from the Ontario Cancer Tumour Registry, with a diagnosis of primary breast cancer in 2003.
RESULTS:

With the exception changes in a Physical well-being subscale and a relationship with doctor subscale, Essiac did not have a significant effect on HR-QOL or mood states. Even for Physical well-being and relationship with doctor, Essiac seemed to have a negative effect, with Essiac users doing worse than the non-Essiac users. This might be attributed to the fact that the group of users comprised younger women with more advanced stages of breast cancer, and both of these subgroups of patients have been shown to be at a significantly increased risk for negative mood states and/or a decreased sense of well-being. The women were taking low doses (total daily dose 43.6 +/- 30.8 mL) of Essiac that corresponded to the label directions found on most Essiac products. Friends were the most common source of information, and most women were taking Essiac to boost their immune systems or increase their chances of survival. Only 2 women reported minor adverse events, whereas numerous women reported beneficial effects of Essiac.
CONCLUSIONS:

Essiac does not appear to improve HR-QOL or mood states. Future studies are needed to determine whether other clinical outcomes, such as cancer reoccurrence, are affected by Essiac.

PMID:
    17212569

Vaccine. 2011 Mar 21;29(14):2530-6. Epub 2011 Feb 2.
Effects of Taishan Pinus massoniana pollen polysaccharide on immune response of rabbit haemorrhagic disease tissue inactivated vaccine and on production performance of Rex rabbits.
Wei K, Sun Z, Yan Z, Tan Y, Wang H, Zhu X, Wang X, Sheng P, Zhu R.
Source

College of Animal Science and Technology, Shandong Agricultural University, Taian, Shandong 271018, PR China.
Abstract

Varied doses of Taishan Pinus massoniana pollen polysaccharide (TPPPS) and Astragalus polysaccharide (APS) extracted by hot water extraction and ethanol precipitation method were added to the vaccine in order to prepare polysaccharide-rabbit haemorrhagic disease (RHD) tissue inactivated vaccine. The purpose was to study effects of TPPPS on immune response of RHD tissue inactivated vaccine and on production performance of Rex rabbits. Results showed that each index in groups I, II, III and IV was higher than that in group V, especially groups I, II and IV, the difference between which and group V was much more significant (P<0.05); each index in group I was extremely higher than that in group V (P<0.01); each index in group I was significantly higher than that in groups II, III (P<0.05), and generally no significant difference was observed between groups II and III. The overall level in group IV was slightly lower than that in group I. Each index in the polysaccharide groups reached its peak value later than that in the non-polysaccharide groups did. Results suggested that any dose of TPPPS can enhance immunologic function and production performance of rabbits, and the amount of 400mg per rabbit has the most obvious efficacy. Furthermore, it can extend the immune peak period of RHD tissue inactivated vaccine and the growing peak period of Rex rabbits. TPPPS has generally higher efficiency than APS.

Copyright © 2011 Elsevier Ltd. All rights reserved.

PMID:
    21295100

Food Chem Toxicol. 2010 Jun;48(6):1644-53. Epub 2010 Mar 27.
Protective effects of silica hydride against carbon tetrachloride-induced hepatotoxicity in mice.
Hsu YW, Tsai CF, Chuang WC, Chen WK, Ho YC, Lu FJ.
Source

Department of Applied Chemistry, Chung Shan Medical University, Taichung City, Taiwan.
Abstract

The protective effects of MegaHydrate silica hydride against liver damage were evaluated by its attenuation of carbon tetrachloride (CCl(4))-induced hepatotoxicity in mice. Male ICR mice were orally treated with silica hydride (104, 208 and 520 mg/kg) or silymarin (200 mg/kg) daily, with administration of CCl(4) (1 mL/kg, 20% CCl4 in olive oil) twice a week for eight weeks. The results showed that oral administration of silica hydride significantly reduced the elevated serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), triglyceride (TG), and cholesterol and the level of malondialdehyde (MDA) in the liver that were induced by CCl(4) in mice. Moreover, the silica-hydride treatment was also found to significantly increase the activities of superoxide dismutase (SOD), catalase, and glutathione peroxidase (GSH-Px), as well as increase the GSH content, in the liver. Liver histopathology also showed that silica hydride reduced the incidence of liver lesions induced by CCl(4). The results suggest that silica hydride exhibits potent hepatoprotective effects on CCl(4)-induced liver damage in mice, likely due to both the increase of antioxidant-defense system activity and the inhibition of lipid peroxidation.

Copyright 2010 Elsevier Ltd. All rights reserved.

PMID:
    20350579

J Biol Regul Homeost Agents. 2011 Apr-Jun;25(2):187-94.
Beneficial nutraceutical modulation of cerebral erythropoietin expression and oxidative stress: an experimental study.
Sedriep S, Xia X, Marotta F, Zhou L, Yadav H, Yang H, Soresi V, Catanzaro R, Zhong K, Polimeni A, Chui DH.
Source

Bio-Cell Unit Lab and Analysis Center, Miyazaki, Japan.
Abstract

The main object of this study is to examine the effect of Klamin®, a nutraceutical containing phenylethylamine, phycocyanins, mycosporine-like aminoacids and aphanizomenon flos aquae-phytochrome on the learning and memory ability, the oxidative status and cerebral erythropoietin and its receptor EPO/EPOR system in prematurely senescent (PS) mice. A total of 28 PS mice, selected according to a prior T-maze test, and 26 non-prematurely senescent mice (NPS) mice were chosen. PS animals were divided into 3 groups and followed for 4 weeks: A) normal chow diet; B) added with Klamin® at 20 mg/kg/day (low dose); C) added with Klamin® at 100mg/kg/day (high dose). A further group of NPS mice given either normal food (group D) or high dose Klamin® (group E) was also considered. The behavioral procedures of spatial learning ability (Morris test) showed that PS mice had significantly longer learning time as compared to their NPS counterpart (p<0.01), but this effect was prevented especially in mice supplemented with high-dose Klamin® (p<0.05) which improved performances in NPS mice (p<0.05). High-dose Klamin® supplementation restored the depleted total thiol concentration in the brain observed in PS mice while normalizing their increased malonildialdehyde level (p<0.05). Moreover, the high-dosage only caused a significant upregulation of EPO/EPOR system both in PS and in NPS animals (p<0.05). Taken together, these data suggest that this specific alga Klamath extract has considerable antioxidant and adaptogenic properties, also through a stimulatory effect of cerebral EPO/EPO system.

PMID:
    21880207

Brain. 2011 Apr;134(Pt 4):1061-76. Epub 2011 Mar 7.
Unawareness of deficits in Alzheimer's disease: role of the cingulate cortex.
Amanzio M, Torta DM, Sacco K, Cauda F, D'Agata F, Duca S, Leotta D, Palermo S, Geminiani GC.
Source

Department of Psychology, University of Turin, Via Verdi 10, 10123 Turin, Italy. martina.amanzio@unito.it
Abstract

Unawareness of deficits is a symptom of Alzheimer's disease that can be observed even in the early stages of the disease. The frontal hypoperfusion associated with reduced awareness of deficits has led to suggestions of the existence of a hypofunctioning prefrontal pathway involving the right dorsolateral prefrontal cortex, inferior parietal lobe, anterior cingulate gyri and limbic structures. Since this network plays an important role in response inhibition competence and patients with Alzheimer's disease who are unaware of their deficits exhibit impaired performance in response inhibition tasks, we predicted a relationship between unawareness of deficits and cingulate hypofunctionality. We tested this hypothesis in a sample of 29 patients with Alzheimer's disease (15 aware and 14 unaware of their disturbances), rating unawareness according to the Awareness of Deficit Questionnaire-Dementia scale. The cognitive domain was investigated by means of a wide battery including tests on executive functioning, memory and language. Neuropsychiatric aspects were investigated using batteries on behavioural mood changes, such as apathy and disinhibition. Cingulate functionality was assessed with functional magnetic resonance imaging, while patients performed a go/no-go task. In accordance with our hypotheses, unaware patients showed reduced task-sensitive activity in the right anterior cingulate area (Brodmann area 24) and in the rostral prefrontal cortex (Brodmann area 10). Unaware patients also showed reduced activity in the right post-central gyrus (Brodmann area 2), in the associative cortical areas such as the right parietotemporal-occipital junction (Brodmann area 39) and the left temporal gyrus (Brodmann areas 21 and 38), in the striatum and in the cerebellum. These findings suggest that the unawareness of deficits in early Alzheimer's disease is associated with reduced functional recruitment of the cingulofrontal and parietotemporal regions. Furthermore, in line with previous findings, we also found apathy and disinhibition to be prominent features of the first behavioural changes in unaware patients.

PMID:
    21385751

Panminerva Med. 2006 Mar;48(1):19-26.
Peptide hormones and lung cancer.
Moody TW.
Source

Department of Health and Human Services, National Cancer Institute, Center for Cancer Research, Office of the Director, Bethesda, MD 20892, USA. moodyt@mail.nih.gov
Abstract

Several peptide hormones have been identified which alter the proliferation of lung cancer. Small cell lung cancer (SCLC), which is a neuroendocrine cancer, produces and secretes gastrin releasing peptide (GRP), neurotensin (NT) and adrenomedullin (AM) as autocrine growth factors. GRP, NT and AM bind to G-protein coupled receptors causing phosphatidylinositol turnover or elevated cAMP in SCLC cells. Addition of GRP, NT or AM to SCLC cells causes altered expression of nuclear oncogenes, such as c-fos, and stimulation of growth. Antagonists have been developed for GRP, NT and AM receptors which function as cytostatic agents and inhibit SCLC growth. Growth factor antagonists, such as the NT1 receptor antagonist SR48692, facilitate the ability of chemotherapeutic drugs to kill lung cancer cells. It remains to be determined if GRP, NT and AM receptors will served as molecular targets, for development of new therapies for the treatment of SCLC patients. Non-small cell lung cancer (NSCLC) cells also have a high density of GRP, NT, AM and epidermal growth factor (EGF) receptors. Several NSCLC patients with EGF receptor mutations respond to gefitinib, a tyrosine kinase inhibitor. Gefitinib relieves NSCLC symptoms, maintaining stable disease in patients who are not eligible for systemic chemotherapy. It is important to develop new therapeutic approaches using translational research techniques for the treatment of lung cancer patients.

PMID:
    16633328

Spectrochim Acta A Mol Biomol Spectrosc. 2011 Oct 15;81(1):184-98. Epub 2011 Jun 21.
Antioxidant, electrochemical, thermal, antimicrobial and alkane oxidation properties of tridentate Schiff base ligands and their metal complexes.
Ceyhan G, Celik C, Urus S, Demirtas I, Elmastas M, Tümer M.
Source

Kahramanmaras Sütçü Imam University, Chemistry Department, 46100 K.Maras, Turkey.
Abstract

In this study, two Schiff base ligands (HL(1) and HL(2)) and their Cu(II), Co(II), Ni(II), Pd(II) and Ru(III) metal complexes were synthesized and characterized by the analytical and spectroscopic methods. Alkane oxidation activities of the metal complexes were studied on cyclohexane as substrate. The ligands and their metal complexes were evaluated for their antimicrobial activity against Corynebacterium xerosis, Bacillus brevis, Bacillus megaterium, Bacillus cereus, Mycobacterium smegmatis, Staphylococcus aureus, Micrococcus luteus and Enterococcus faecalis (as Gram-positive bacteria) and Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Yersinia enterocolitica, Klebsiella fragilis, Saccharomyces cerevisiae, and Candida albicans (as Gram-negative bacteria). The antioxidant properties of the Schiff base ligands were evaluated in a series of in vitro tests: 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and reducing power activity of superoxide anion radical generated non-enzymatic systems. Electrochemical and thermal properties of the compounds were investigated.

Copyright © 2011 Elsevier B.V. All rights reserved.

PMID:
    21752697

Neurosci Lett. 2011 Feb 11;489(3):168-71. Epub 2010 Dec 13.
Nicotine modulates expression of dynamin 1 in rat brain and SH-SY5Y cells.
Xu Q, Li MD.
Source

Institute of Biological Science and Bioengineering, Beijing Jiaotong University, Beijing 100044, China.
Abstract

Our previous genetic and proteomic studies demonstrated that dynamin 1 is significantly associated with nicotine dependence (ND) in human smokers and its expression is highly modulated by nicotine in the brains of animals. To provide further molecular evidence for the involvement of dynamin 1 in the etiology of ND, we investigated the regulatory effect of nicotine on the expression of dynamin 1 using both in vivo and in vitro approaches. With quantitative real-time RT-PCR, we found that dynamin 1 mRNA was significantly downregulated, by 30%, 31%, and 38%, in the striatum, hippocampus, and medial basal hypothalamus (MBH), respectively, of nicotine-treated rats (P<0.01 for all three regions). Further, dynamin 1 protein was downregulated by nicotine in the ventral tegmental area (VTA: 39.5%; P<0.01), hippocampus (13.4%, P<0.05), MBH (24.6%, P<0.01), and amygdala (15.7%, P<0.05). We also determined the effect of nicotine on human SH-SY5Y cells and found that dynamin 1 mRNA was significantly down-regulated by nicotine after treatment (51.4%; P<0.01), and a consistent decrease in the amount of the protein was also observed (36.6%; P<0.05). Taken together, our findings provide further molecular evidence for the involvement of dynamin 1 in the etiology of ND.

© 2010 Elsevier Ireland Ltd. All rights reserved.

PMID:
    21159320

J Biol Chem. 2011 Jun 17;286(24):21865-75. Epub 2011 Apr 22.
Glutathionylation acts as a control switch for uncoupling proteins UCP2 and UCP3.
Mailloux RJ, Seifert EL, Bouillaud F, Aguer C, Collins S, Harper ME.
Source

Department of Biochemistry, Microbiology, and Immunology, Faculty of Medicine, University of Ottawa, Ottawa, Ontario, Canada, K1H 8M5.
Abstract

The mitochondrial uncoupling proteins 2 and 3 (UCP2 and -3) are known to curtail oxidative stress and participate in a wide array of cellular functions, including insulin secretion and the regulation of satiety. However, the molecular control mechanism(s) governing these proteins remains elusive. Here we reveal that UCP2 and UCP3 contain reactive cysteine residues that can be conjugated to glutathione. We further demonstrate that this modification controls UCP2 and UCP3 function. Both reactive oxygen species and glutathionylation were found to activate and deactivate UCP3-dependent increases in non-phosphorylating respiration. We identified both Cys(25) and Cys(259) as the major glutathionylation sites on UCP3. Additional experiments in thymocytes from wild-type and UCP2 null mice demonstrated that glutathionylation similarly diminishes non-phosphorylating respiration. Our results illustrate that UCP2- and UCP3-mediated state 4 respiration is controlled by reversible glutathionylation. Altogether, these findings advance our understanding of the roles UCP2 and UCP3 play in modulating metabolic efficiency, cell signaling, and oxidative stress processes.

PMID:
    21515686

Glycobiology. 2004 Jun;14(6):501-10. Epub 2004 Jan 22.
Chemical and biological characterization of a polysaccharide biological response modifier from Aloe vera L. var. chinensis (Haw.) Berg.
Leung MY, Liu C, Zhu LF, Hui YZ, Yu B, Fung KP.
Source

Institute of Chinese Medicine, Chinese University of Hong Kong, Shatin, N.T., Hong Kong, People's Republic of China.
Abstract

Three purified polysaccharide fractions designated as PAC-I, PAC-II, and PAC-III were prepared from Aloe vera L. var. chinensis (Haw.) Berg. by membrane fractionation and gel filtration HPLC. The polysaccharide fractions had molecular weights of 10,000 kDa, 1300 kDa, and 470 kDa, respectively. The major sugar residue in the polysaccharide fractions is mannose, which was found to be 91.5% in PAC-I, 87.9% in PAC-II, and 53.7% in PAC-III. The protein contents in the polysaccharide fractions was undetectable. NMR study of PAC-I and PAC-II demonstrated the polysaccharides shared the same structure. The main skeletons of PAC-I and PAC-II are beta-(1-->4)-D linked mannose with acetylation at C-6 of manopyranosyl. The polysaccharide fractions stimulated peritoneal macrophages, splenic T and B cell proliferation, and activated these cells to secrete TNF-alpha, IL-1 beta, INF-gamma, IL-2, and IL-6. The polysaccharides were nontoxic and exhibited potent indirect antitumor response in murine model. PAC-I, which had the highest mannose content and molecular weight, was found to be the most potent biological response modifier of the three fractions. Our results suggested that the potency of aloe polysaccharide fraction increases as mannose content and molecular weight of the polysaccharide fraction increase.

PMID:
    14739149

Curr Med Chem. 2000 Jul;7(7):715-29.
Immunomodulation and anti-cancer activity of polysaccharide-protein complexes.
Ooi VE, Liu F.
Source

Department of Biology, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong.
Abstract

In the last three decades, numerous polysaccharides and polysaccharide-protein complexes have been isolated from mushrooms and used as a source of therapeutic agents. The most promising biopharmacological activities of these biopolymers are their immunomodulation and anti-cancer effects. They are mainly present as glucans with different types of glycosidic linkages such as (1-->3), (1-->6)-beta-glucans and (1-->3)-alpha-glucans, and as true herteroglycans, while others mostly bind to protein residues as polysaccharide-protein complexes. Three antitumor mushroom polysaccharides, i.e. lentinan, schizophyllan and protein-bound polysaccharide (PSK, Krestin), isolated respectively, from Lentinus edodes, Schizophyllum commune and Coriolus versicolor, have become large market items in Japan. Lentinan and schizophyllan are pure beta-glucans, whereas PSK is a protein-bound beta-glucan. A polysaccharide peptide (PSP), isolated from a strain of Coriolus versicolor in China, has also been widely used as an anti-cancer and immunomodulatory agent. Although the mechansim of their antitumor action is still not completely clear, these polysaccharides and polysaccharide-protein complexes are suggested to enhance cell-mediated immune responses in vivo and in vitro and act as biological response modifiers. Potentiation of the host defense system may result in the activation of many kinds of immune cells that are vitally important for the maintenance of homeostasis. Polysaccharides or polysaccharide-protein complexes are considered as multi-cytokine inducers that are able to induce gene expression of vaious immunomodulatory cytokines and cytokine receptors. Some interesting studies focus on investigation of the relationship between their structure and antitumor activity, elucidation of their antitumor mechanism at the molecular level, and improvement of their various biological activities by chemical modifications.

PMID:
    10702635

Cytotechnology. 2000 Jul;33(1-3):247-51.
Mannosylerythritol lipid increases levels of galactoceramide in and neurite outgrowth from PC12 pheochromocytoma cells.
Shibahara M, Zhao X, Wakamatsu Y, Nomura N, Nakahara T, Jin C, Nagaso H, Murata T, Yokoyama KK.
Source

Tsukuba Life Science Center, RIKEN (The Institute of Physical and Chemical Research), 3-1-1 Koyadai, Tsukuba, Ibaraki, 305-0074, Japan.
Abstract

We report here that a microbial extracellular glycolipid,mannosylerythritol lipid (MEL), induces the outgrowth ofneurites from and enhances the activity of acetylcholinesterase(AChE) in PC12 pheochromocytoma cells. Furthermore, treatment ofPC12 cells with MEL increased levels of galactosylceramide(Galbeta1-1'Cer; GalCer). Exposure of PC12 cells to exogenous GalCer caused the dose-dependent outgrowth ofneurites. By contrast, treatment of PC12 cells with nerve growthfactor (NGF) did not increase the level of GalCer in the cells. The neurite-related morphological changes induced by GalCerdifferend from those induced by NGF, indicating differencesbetween the signal transduction pathways triggered by NGF and by GalCer.

PMID:
    19002832

J Biochem. 2003 Apr;133(4):541-52.
Molecular action mode of Hippospongic acid A, an inhibitor of gastrulation of starfish embryos.
Mizushina Y, Murakami C, Takikawa H, Kasai N, Xu X, Mori K, Oshige M, Yamaguchi T, Saneyoshi M, Shimazaki N, Koiwai O, Yoshida H, Sugawara F, Sakaguchi K.
Source

Department of Nutritional Science, Kobe-Gakuin University, Nishi-ku, Kobe, Hyogo 651-2180. mizushin@nutr.kobegakuin.ac.jp
Abstract

Hippospongic acid A (HA-A) is a novel natural triterpene metabolite that exhibits inhibitory activity against the gastrulation of starfish embryos isolated from a marine sponge, Hippospongia sp. We succeeded in chemically synthesizing the natural enantiomer and the racemate HA-A. In this study, we examined its action mode in vitro. HA-A was a rare compound that could selectively but uniformly inhibit the activities of all the vertebrate DNA polymerases tested such as alpha, beta, delta, epsilon, eta, kappa, and lambda, in the IC(50) range of 5.9-17.6 microM, and interestingly also those of human DNA topoisomerases I and II (IC(50) = 15-25 microM). HA-A exhibited no inhibitory effect on DNA polymerases from insects, plants and prokaryotes, or on many other DNA metabolic enzymes. HA-A was an inhibitor specific to DNA polymerases and DNA topoisomerases from vertebrates, but not selective as to a subclass species among the enzymes. Since DNA polymerase beta is the smallest, we used it to analyze the biochemical relationship with HA-A. Biochemical, BIAcore and computer modeling analyses demonstrated that HA-A bound selectively to the N-terminal 8 kDa DNA template-binding domain of DNA polymerase beta, and HA-A inhibited the ssDNA binding activity. HA-A could prevent the growth of NUGC-3 cancer cells at both the G1 and G2/M phases, and induce apoptosis in the cells. The LD(50) value was 9.5 microM, i.e. in the same range as for the enzyme inhibition. Therefore, we concluded that one molecular basis of the gastrulation of starfish embryos is a process that requires DNA polymerases and DNA topoisomerases, and subsequently the gastrulation was inhibited by HA-A. We also discussed the in vivo role of HA-A.

PMID:
    12761303

Curr Med Chem. 2007;14(9):955-67.
Inhibitory effect on replicative DNA polymerases, human cancer cell proliferation, and in vivo anti-tumor activity by glycolipids from spinach.
Maeda N, Hada T, Yoshida H, Mizushina Y.
Source

Laboratory of Food and Nutritional Sciences, Department of Nutritional Science, Kobe-Gakuin University, 518 Arise, Ikawadanicho, Nishi-ku, Kobe, Hyogo 651-2180, Japan.
Abstract

We succeeded in purifying a major glycolipids fraction (i.e., Fraction-II) in the class of monogalactosyl diacylglycerol (MGDG), digalactosyl diacylglycerol (DGDG) and sulfoquinovosyl diacylglycerol (SQDG) from spinach using hydrophobic column chromatography. Fraction-II inhibited the activities of replicative DNA polymerases (pols) such as alpha, delta and epsilon, and mitochondrial pol gamma with IC(50) values of 43-79 microg/ml, but had no influence on the activity of repair-related pols beta and lambda. MGDG, DGDG, SQDG were purified from Fraction-II of spinach using silica gel column chromatography, and SQDG was the strongest inhibitor of mammalian pols in the three glycolipids. Therefore, SQDG and its related compounds were chemically synthesized, and the sulfate group and fatty acid moiety of the compound were suggested to be important for pol inhibition. These glycolipids showed no effect even on the activities of plant pols, prokaryotic pols and other DNA metabolic enzymes such as T4 polynucleotide kinase, T7 RNA polymerase and deoxyribonuclease I. Fraction-II also inhibited the proliferation of human cervix carcinoma (HeLa) cells with LD(50) values of 57 microg/ml, and could halt the cell cycle at the G1-phase, and subsequently induced severe apoptosis. In an in vivo anti-tumor assay on nude mice bearing solid tumors of HeLa cells, Fraction-II was shown to be a promising suppressor of solid tumors. Histopathological examination revealed that tumor necrosis with hemorrhage was significantly enhanced with Fraction-II in vivo. The spinach Fraction-II containing SQDG might be a potent anti-tumor compound, and may be a healthy food substance with anti-tumor activity.

PMID:
    17439396

J Biochem Mol Biol Biophys. 2002 Oct;6(5):341-5.
Pleurotus Eous mushroom lectin (PEL) with mixed carbohydrate inhibition and antiproliferative activity on tumor cell lines.
Mahajan RG, Patil SI, Mohan DR, Shastry P.
Source

Division of Biochemical Sciences, National Chemical Laboratory, Pune 411 008, India. padmashastry@hotmail.com
Abstract

A novel Pleurotus eous mushroom lectin (PEL) having mixed binding specificity was purified to homogeneity from the fruitbodies of P. eous. The lectin showed monomer weight of 16 kDa and was a glycoprotein having a 9% neutral sugar content. The antiproliferative activity of PEL was tested on four human tumor cell lines. A 50% inhibition of proliferation was demonstrated in MCF-7, K562 and Hep2 cell lines at the lowest concentration (2 microg/ml) of lectin tested. SK-N-MC cell line showed 50% inhibition at 50 microg/ml of PEL. The inhibitory activity of PEL was not associated with toxicity to cell lines.

PMID:
    12385970

Blood. 2011 Aug 26. [Epub ahead of print]
Hepcidin regulation by innate immune and infectious stimuli.
Armitage AE, Eddowes LA, Gileadi U, Cole S, Spottiswoode N, Selvakumar TA, Ho LP, Townsend AR, Drakesmith H.
Source

Molecular Immunology Group, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom;
Abstract

Hepcidin controls the levels and distribution of iron, an element whose availability can influence the outcome of infections. We investigated hepcidin regulation by infection-associated cytokines, pathogen-derived molecules, and whole pathogens in vitro and in vivo. We found that IL-22, an effector cytokine implicated in responses to extracellular infections, caused IL-6-independent hepcidin upregulation in human hepatoma cells, suggesting it might represent an additional inflammatory hepcidin agonist. Like IL-6, IL-22 caused phosphorylation of STAT3 and synergized with BMP6 potentiating hepcidin induction. In human leukocytes, IL-6 caused potent, transient hepcidin upregulation that was augmented by TGF-ß1. Pathogen-derived TLR agonists also stimulated hepcidin, most notably the TLR5 agonist flagellin in an IL-6-dependent manner. In contrast, leukocyte hepcidin induction by heat-killed Candida albicans hyphae was IL-6-independent, but partially TGF-ß-dependent. In a murine acute systemic candidiasis model, Candida albicans strongly stimulated hepcidin, accompanied by a major reduction in transferrin saturation. Similarly, hepcidin was upregulated with concomitant lowering of serum iron during acute murine Influenza A/PR/8/34 virus (H1N1) infection. This intracellular pathogen also stimulated hepcidin expression in leukocytes and hepatoma cells. Together, these results indicate that hepcidin induction represents a component of the innate immune response to acute infection, with the potential to affect disease pathogenesis.

PMID:
    21873546

J Rheumatol. 2011 Oct;38(10):2153-9. Epub 2011 Sep 1.
Serum hepcidin: a direct link between anemia of inflammation and coronary artery atherosclerosis in patients with rheumatoid arthritis.
Abdel-Khalek MA, El-Barbary AM, Essa SA, Ghobashi AS.
Source

Tanta Faculty of Medicine, Rheumatology and Rehabilitation Department, Elgesh Street, Tanta, Gharbeia, Egypt. ml_barbary@yahoo.com.
Abstract
OBJECTIVE:

To investigate the role of hepcidin as an inducer of anemia of inflammation in patients with rheumatoid arthritis (RA), and its correlation to coronary artery atherosclerosis.
METHODS:

Our study included 60 patients with RA and 20 healthy controls. Anemic RA patients with serum transferrin receptors/log ferritin (sTfR-F) index value < 1.5 were classified as having pure anemia of chronic disease (ACD), and patients with sTfR-F index value > 1.5 were classified as having anemia of chronic disease with coexistent iron deficiency anemia (ACD+IDA). Measurements were taken for Disease Activity Score for 28 joints (DAS28), Modified Health Assessment Questionnaire (MHAQ), erythrocyte sedimentation rate (ESR), high sensitivity C-reactive protein (hsCRP), rheumatoid factor (RF), lipid profile, serum interleukin 6 (IL-6), tumor necrosis factor-a, iron studies, and serum hepcidin. Coronary calcium score (CCS) was measured using multislice spiral computed tomography as a marker of atherosclerosis.
RESULTS:

Serum hepcidin was found to be higher in anemic patients with RA than in controls (p < 0.001), and higher in the pure ACD subgroup than in the ACD+IDA subgroup (p < 0.001). Hepcidin concentration was positively correlated with disease duration, ESR, hsCRP, RF, DAS28, MHAQ, serum ferritin, IL-6, and mean CCS and inversely correlated with hemoglobin, sTfR, and the sTfR-F index.
CONCLUSION:

Hepcidin can be considered a key inducer of anemia of inflammation in patients with RA. This inflammation was proved to be directly linked to coronary artery atherosclerosis. The correlations between serum hepcidin with disease activity and IL-6 raise the possibility of using it as a surrogate marker for disease activity.

PMID:
    21885483

Blood. 2011 Aug 26. [Epub ahead of print]
TMPRSS6 rs855791 modulates hepcidin transcription in vitro and serum hepcidin levels in normal individuals.
Nai A, Pagani A, Silvestri L, Campostrini N, Corbella M, Girelli D, Traglia M, Toniolo D, Camaschella C.
Source

Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan, Italy;
Abstract

The iron hormone hepcidin is inhibited by matriptase-2, a liver serine-protease encoded by TMPRSS6 gene. Cleaving the BMP-coreceptor hemojuvelin, matriptase-2 impairs the BMP/SMAD signaling pathway, downregulates hepcidin and facilitates iron absorption. TMPRSS6 inactivation causes iron-deficiency-anemia refractory to iron administration both in humans and mice. Genome wide association studies have shown that the SNP rs855791, which causes the matriptase-2 V736A amino acid substitution, is associated with variations of serum iron, transferrin saturation, hemoglobin and erythrocyte traits. Here we show that in vitro matriptase-2 736(A) inhibits hepcidin more efficiently than 736(V). Moreover, in a genotyped population, after exclusion of samples with iron deficiency and inflammation, hepcidin, hepcidin/transferrin saturation and hepcidin/ferritin ratios were significantly lower and iron parameters were consistently higher in homozygotes 736(A) than in 736(V). Our results indicate that rs855791 is a TMPRSS6 functional variant and strengthen that even a partial inability to modulate hepcidin influences iron parameters and indirectly erythropoiesis.

PMID:
    21873547

Gene. 2008 May 31;415(1-2):40-8. Epub 2008 Feb 26.
Molecular evolution and characterization of hepcidin gene products in vertebrates.
Hilton KB, Lambert LA.
Source

Department of Biology, Chatham University, Woodland Road, Pittsburgh, PA 15232, United States.
Abstract

Antimicrobial peptides (AMPs) include a diverse group of gene-encoded molecules that play a role in innate defense in many organisms. Evolutionary analyses of the AMP genes can be challenging because of gene duplication and diversification. Recently discovered, hepcidins are small, cysteine-rich antimicrobial peptides that also function as hormonal regulators of iron homeostasis. In this paper we investigated the organization, expression and molecular evolution of hepcidin. From searches of the literature and public genomic databases we collected 68 different hepcidin gene products from 51 different species, all among the vertebrates. Although some species have multiple hepcidin homologues, we suggest that each contains only one copy that functions as an iron regulator. Despite the recent report of hepcidin sequences in the pigeon (Fu, Y.M., Li, S.P., Wu, Y.F., Chang, Y.Z., 2007. Identification and expression analysis of hepcidin-like cDNAs from pigeon (Columba livia). Mol. Cell. Biochem. 305, 191-197.), searches of the chicken genomic, EST, and HTGS databases did not reveal any evidence of the presence of this gene in birds. This, along with the absence of reported avian transferrin receptor 2 and hemojuvelin sequences, suggests that iron homeostasis in birds may be regulated by an alternative mechanism.

PMID:
    18395368

Carbohydr Res. 2011 Oct 18;346(14):2255-9. Epub 2011 Jul 24.
A comparative study of antioxidative activities of cell-wall polysaccharides.
Pristov JB, Mitrovic A, Spasojevic I.
Source

Institute for Multidisciplinary Research, University of Belgrade, Belgrade, Serbia.
Abstract

Oxidative burst in plants is elicited by biotic and abiotic stressors. Analogously to some monosaccharides which act as intracellular antioxidants, cell-wall polysaccharides may be in charge of buffering free-radical production in the extracellular compartment under pronounced prooxidative settings. Although a wide range of plant polysaccharides have been examined for their antioxidative properties, this usually has not been done in a coherent and comparative manner and against biologically relevant reactive species. Here we show that different cell-wall polysaccharides, cellulose, pectin, d-galacto-d-mannan, arabinogalactan, and xylan, exhibit distinctive antioxidative activities against the hydroxyl radical (()OH)-generating Fenton reaction and superoxide. We found, using an EPR spin-trapping method, that the main carriers of 'anti-Fenton' activity in the plant cell wall are pectin and xylan. They most likely act by binding metal ions in such a manner to allow the Fenton reaction, after which they scavenge ()OH. Such a mode of action is preferred by cells resulting in a safe degradation of H(2)O(2). On the other hand, the polysaccharides examined showed similar superoxide scavenging capacities. We propose that plants may employ different antioxidative characteristics of polysaccharides to regulate their redox status by modifying the composition of the cell wall.

Copyright © 2011 Elsevier Ltd. All rights reserved.

PMID:
    21880306

J Endocrinol. 2011 Sep 8. [Epub ahead of print]
5{alpha}-REDUCED GLUCOCORTICOIDS - A STORY OF NATURAL SELECTION.
Nixon M, Upreti R, Andrew R.
Source

M Nixon, Endocrinology, Queen's Medical Research Institute, University of Edinburgh,, Edinburgh , United Kingdom.
Abstract

5a-Reduced glucocorticoids are formed when one of the two isozymes of 5a-reductase reduce the ?4-5 double bond in the A-ring of glucocorticoids. These steroids are largely viewed inert, despite acceptance that other 5a-dihydro steroids, eg 5a-dihydrotestosterone, retain or have increased activity at their cognate receptors. However recent findings suggest that 5a-reduced metabolites of corticosterone have dissociated actions at glucocorticoid receptors in vivo and in vitro and thus are potential candidates for safer anti-inflammatory steroids.5a-Dihydro- and 5a-tetrahydro-corticosterone can bind with glucocorticoid receptors but interest in these compounds had been limited, since they only weakly activated metabolic gene transcription. However a greater understanding of the signalling mechanisms has revealed that transactivation represents only one mode of signalling via the glucocorticoid receptor and recently the abilities of 5a-reduced glucocorticoids to suppress inflammation have been demonstrated in vitro and in vivo.Thus the balance of parent glucocorticoid and its 5a-reduced metabolite may critically affect the profile of glucocorticoid receptor signalling. 5a-Reduction of glucocorticoids is up-regulated in liver in metabolic disease and may represent a pathway which both protects from glucocorticoid induced fuel dyshomeostasis and the concomitant inflammatory insult. Therefore 5a-reduced steroids provide hope for drug development, but also may act as biomarkers of the inflammatory status of the liver in metabolic disease. With these proposals in mind, careful attention must be paid to the possible adverse metabolic effects of 5a-reductase inhibitors, drugs which are commonly administered long-term for the treatment of benign prostatic hyperplasia.

PMID:
    21903862

Neurobiol Aging. 2006 Jul;27(7):1010-9. Epub 2005 Jun 23.
Quantitative proteomics analysis of differential protein expression and oxidative modification of specific proteins in the brains of old mice.
Poon HF, Vaishnav RA, Getchell TV, Getchell ML, Butterfield DA.
Source

Department of Chemistry, Center of Mambrane Sciences, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40506-0055, USA.
Abstract

The brain is susceptible to oxidative stress, which is associated with age-related brain dysfunction, because of its high content of peroxidizable unsaturated fatty acids, high oxygen consumption per unit weight, high content of key components for oxidative damage, and the relative scarcity of antioxidant defense systems. Protein oxidation, which results in functional disruption, is not random but appears to be associated with increased oxidation in specific proteins. By using a proteomics approach, we have compared the protein levels and specific protein carbonyl levels, an index of oxidative damage in the brains of old mice, to these parameters in the brains of young mice and have identified specific proteins that are altered as a function of aging. We show here that the expression levels of dihydropyrimidinase-like 2 (DRP2), alpha-enolase (ENO1), dynamin-1 (DNM1), and lactate dehydrogenase 2 (LDH2) were significantly increased in the brains of old versus young mice; the expression levels of three unidentified proteins were significantly decreased. The specific carbonyl levels of beta-actin (ACTB), glutamine synthase (GS), and neurofilament 66 (NF-66) as well as a novel protein were significantly increased, indicating protein oxidation, in the brains of old versus young mice. These results were validated by immunochemistry. In addition, enzyme activity assays demonstrated that oxidation was associated with decreased GS activity, while the activity of lactate dehydrogenase was unchanged in spite of an up-regulation of LDH2 levels. Several of the up-regulated and oxidized proteins in the brains of old mice identified in this report are known to be oxidized in neurodegenerative diseases as well, suggesting that these proteins may be particularly susceptible to processes associated with neurodegeneration. Our results establish an initial basis for understanding protein alterations that may lead to age-related cellular dysfunction in the brain.

PMID:
    15979213

Cell Mol Neurobiol. 2010 Nov;30(8):1351-7.
Dynamin and myosin regulate differential exocytosis from mouse adrenal chromaffin cells.
Chan SA, Doreian B, Smith C.
Source

Case Western Reserve University, 2109 Adelbert Road, Cleveland, OH 44106-4970, USA. shyue-an.chan@case.edu
Abstract

Neuroendocrine chromaffin cells of the adrenal medulla represent a primary output for the sympathetic nervous system. Chromaffin cells release catecholamine as well as vaso- and neuro-active peptide transmitters into the circulation through exocytic fusion of large dense-core secretory granules. Under basal sympathetic activity, chromaffin cells selectively release modest levels of catecholamines, helping to set the "rest and digest" status of energy storage. Under stress activation, elevated sympathetic firing leads to increased catecholamine as well as peptide transmitter release to set the "fight or flight" status of energy expenditure. While the mechanism for catecholamine release has been widely investigated, relatively little is known of how peptide transmitter release is regulated to occur selectively under elevated stimulation. Recent studies have shown selective catecholamine release under basal stimulation is accomplished through a transient, restricted exocytic fusion pore between granule and plasma membrane, releasing a soluble fraction of the small, diffusible molecules. Elevated cell firing leads to the active dilation of the fusion pore, leading to the release of both catecholamine and the less diffusible peptide transmitters. Here we propose a molecular mechanism regulating the activity-dependent dilation of the fusion pore. We review the immediate literature and provide new data to formulate a working mechanistic hypothesis whereby calcium-mediated dephosphorylation of dynamin I at Ser-774 leads to the recruitment of the molecular motor myosin II to actively dilate the fusion pore to facilitate release of peptide transmitters. Thus, activity-dependent dephosphorylation of dynamin is hypothesized to represent a key molecular step in the sympatho-adrenal stress response.

PMID:
    21061163

BMC Complement Altern Med. 2011 Jul 25;11:58.
Polysaccharides from Agaricus bisporus and Agaricus brasiliensis show similarities in their structures and their immunomodulatory effects on human monocytic THP-1 cells.
Smiderle FR, Ruthes AC, van Arkel J, Chanput W, Iacomini M, Wichers HJ, Van Griensven LJ.
Source

Plant Research International, Wageningen University and Research, Bornsesteeg 1, 6708 PD Wageningen, The Netherlands.
Abstract
BACKGROUND:

Mushroom polysaccharides have traditionally been used for the prevention and treatment of a multitude of disorders like infectious illnesses, cancers and various autoimmune diseases. Crude mushroom extracts have been tested without detailed chemical analyses of its polysaccharide content. For the present study we decided to chemically determine the carbohydrate composition of semi-purified extracts from 2 closely related and well known basidiomycete species, i.e. Agaricus bisporus and A. brasiliensis and to study their effects on the innate immune system, in particular on the in vitro induction of pro-inflammatory cytokines, using THP-1 cells.
METHODS:

Mushroom polysaccharide extracts were prepared by hot water extraction and precipitation with ethanol. Their composition was analyzed by GC-MS and NMR spectroscopy. PMA activated THP-1 cells were treated with the extracts under different conditions and the production of pro-inflammatory cytokines was evaluated by qPCR.
RESULTS:

Semi-purified polysaccharide extracts of A. bisporus and A. brasiliensis (= blazei) were found to contain (1?6),(1?4)-linked a-glucan, (1?6)-linked ß-glucan, and mannogalactan. Their proportions were determined by integration of 1H-NMR signs, and were considerably different for the two species. A. brasiliensis showed a higher content of ß-glucan, while A. bisporus presented mannogalactan as its main polysaccharide. The extracts induced a comparable increase of transcription of the pro-inflammatory cytokine genes IL-1ß and TNF-a as well as of COX-2 in PMA differentiated THP-1 cells. Pro-inflammatory effects of bacterial LPS in this assay could be reduced significantly by the simultaneous addition of A. brasiliensis extract.
CONCLUSIONS:

The polysaccharide preparations from the closely related species A. bisporus and A. brasiliensis show major differences in composition: A. bisporus shows high mannogalactan content whereas A. brasiliensis has mostly ß-glucan. Semi-purified polysaccharide extracts from both Agaricus species stimulated the production of pro-inflammatory cytokines and enzymes, while the polysaccharide extract of A. brasiliensis reduced synthesis of these cytokines induced by LPS, suggesting programmable immunomodulation.

PMID:
    21787425

FASEB J. 2008 Mar;22(3):703-12. Epub 2007 Oct 10.
Methylene blue delays cellular senescence and enhances key mitochondrial biochemical pathways.
Atamna H, Nguyen A, Schultz C, Boyle K, Newberry J, Kato H, Ames BN.
Source

Nutrition & Metabolism Center, Children's Hospital Oakland Research Institute, 5700 Martin Luther King Jr. Way, Oakland, CA 94609-1673, USA. hatamna@chori.org
Abstract

Methylene blue (MB) has been used clinically for about a century to treat numerous ailments. We show that MB and other diaminophenothiazines extend the life span of human IMR90 fibroblasts in tissue culture by >20 population doubling (PDLs). MB delays senescence at nM levels in IMR90 by enhancing mitochondrial function. MB increases mitochondrial complex IV by 30%, enhances cellular oxygen consumption by 37-70%, increases heme synthesis, and reverses premature senescence caused by H2O2 or cadmium. MB also induces phase-2 antioxidant enzymes in hepG2 cells. Flavin-dependent enzymes are known to use NAD(P)H to reduce MB to leucomethylene blue (MBH2), whereas cytochrome c reoxidizes MBH2 to MB. Experiments on lysates from rat liver mitochondria suggest the ratio MB/cytochrome c is important for the protective actions of MB. We propose that the cellular senescence delay caused by MB is due to cycling between MB and MBH2 in mitochondria, which may partly explain the increase in specific mitochondrial activities. Cycling of MB between oxidized and reduced forms may block oxidant production by mitochondria. Mitochondrial dysfunction and oxidative stress are thought to be key aberrations that lead to cellular senescence and aging. MB may be useful to delay mitochondrial dysfunction with aging and the decrease in complex IV in Alzheimer disease.

PMID:
    17928358

Antioxid Redox Signal. 2009 May;11(5):949-62.
Fragrant unsaturated aldehydes elicit activation of the Keap1/Nrf2 system leading to the upregulation of thioredoxin expression and protection against oxidative stress.
Masutani H, Otsuki R, Yamaguchi Y, Takenaka M, Kanoh N, Takatera K, Kunimoto Y, Yodoi J.
Source

Department of Biological Responses, Institute for Virus Research, Kyoto University, Kyoto, Japan. hmasutan@virus.kyoto-u.ac.jp
Abstract

Thioredoxin, a key molecule in redox regulation, and many redox enzymes are regulated through the antioxidant responsive element (ARE). To search for antioxidative constituents, we screened extracts from vegetables and found that the extracts of Perilla frutescens and Artemisia princeps have potent thioredoxin-inducing activities. By activity-guided purification of Perilla frutescens extracts, we identified perillaldehyde as a novel thioredoxin inducer. Fragrant unsaturated aldehydes, such as trans-cinnamaldehyde, safranal, 2,4-octadienal, citral, trans-2, cis-6-nonadienal, and trans-2-hexenal showed the ability to activate ARE. Perillaldehyde-induced activation through the ARE was suppressed by the overexpression of wild-type Keap1, whereas sulforaphane-induced activation seemed to be partially suppressed. Mutant Keap1 (R272A/K287A or C273A/C288A) did not suppress this activation. Pretreatment with perillaldehyde reduced the H(2)O(2)-induced cytotoxicity. Thus, we show that fragrant unsaturated aldehydes from edible plants are novel thioredoxin inducers and ARE activators and may be beneficial for protection against oxidative stress-induced cellular damage. These results also suggest that perillaldehyde activates the Nrf2-Keap1 system and that the lysine and arginine residues juxtaposed to the critical cysteine residues of Keap1 are required for signal sensing.

PMID:
    19123792

J Food Sci. 2011 Mar;76(2):C250-6. doi: 10.1111/j.1750-3841.2010.02010.x. Epub 2011 Feb 3.
Neuroprotective effect of caffeoylquinic acids from Artemisia princeps Pampanini against oxidative stress-induced toxicity in PC-12 cells.
Lee SG, Lee H, Nam TG, Eom SH, Heo HJ, Lee CY, Kim DO.
Source

Dept of Food Science and Technology, Inst of Life Sciences and Resources, Kyung Hee Univ, Yongin, Gyeonggi 446-701, Republic of Korea.
Abstract

Phenolics in dry Artemisia princeps Pampanini, an herbal plant traditionally consumed as food ingredients in Korea was extracted, fractionated, and quantified as well as evaluated for its neuroprotection for PC-12 cells. Whole extract had 5,852 mg gallic acid equivalents/100 g of total phenolics and 6,274 mg and 9,698 mg vitamin C equivalents/100 g of antioxidant capacities assayed by DPPH and ABTS radicals, respectively. The fraction extracted with n-butanol had the highest levels of total phenolics and antioxidant capacity than the other fractions (n-hexane, chloroform, ethyl acetate, and water). Using a reversed-phase HPLC system, caffeoylquinic acid (CQA) and its derivatives such as 3-CQA, 4-CQA, 5-CQA, 1,5-diCQA, 3,4-diCQA, 3,5-diCQA, and 4,5-diCQA were isolated and quantified. The whole extract and its n-butanol fraction yielded 3,5-diCQA with the highest amount, which consisted of approximately 36.8% and 33.5%, respectively. The whole extract, the n-butanol fraction, and 3,5-diCQA showed neuroprotective effect on PC-12 cells under the insult of amyloid ß peptide in a dose-dependent manner. Treatments of the whole extract and the n-butanol fraction for PC-12 cells under oxidative stress increased approximately 1.6 and 2.4 times higher cell viability, compared with the control without treatments. For PC-12 cells treated with 3,5-diCQA, intracellular oxidative stress decreased by 51.3% and cell viability increased up to 2.8 times compared to the control with oxidative insult of amyloid ß peptide only. These results indicate that phenolics from A. princeps Pampanini alleviated the oxidative stress and enhanced the viability of PC-12 cells, suggesting that it may be applied as a dietary antineurodegenerative agent in functional foods.

PMID:
    21535743

Food Funct. 2011 Sep 7. [Epub ahead of print]
Dietary chromones as antioxidant agents-the structural variable.
Dias MM, Machado NF, Marques MP.
Source

Research Unit "Molecular Physical Chemistry", University of Coimbra, Portugal.
Abstract

This study reports an evaluation of the free radical scavenging ability of a series of chromone derivatives, in the light of their structural features and conformational behaviour. The 2,2-diphenyl-1-picrylhydrazyl radical (DPPH?) test for the assessment of radical scavenging properties was applied, and the interpretation of the experimental results was assisted by ab initio theoretical approaches that allowed relevant parameters, such as the enthalpy of formation of the radical species, to be predicted. From the eighteen tested compounds, three-fisetin, luteolin and quercetin-are shown to act as effective antiradicals. Consistent structure-activity relationships (SARs) were established regarding the antioxidant role of this type of chromone-based system.

PMID:
    21897966

PLoS One. 2011;6(5):e19859. Epub 2011 May 31.
Plasma corticosterone activates SGK1 and induces morphological changes in oligodendrocytes in corpus callosum.
Miyata S, Koyama Y, Takemoto K, Yoshikawa K, Ishikawa T, Taniguchi M, Inoue K, Aoki M, Hori O, Katayama T, Tohyama M.
Source

Department of Anatomy and Neuroscience, Graduate School of Medicine, Osaka University, Suita, Osaka, Japan. smiyata@anat2.med.osaka-u.ac.jp
Abstract

Repeated stressful events are known to be associated with onset of depression. Further, stress activates the hypothalamic-pituitary-adrenocortical (HPA) system by elevating plasma cortisol levels. However, little is known about the related downstream molecular pathway. In this study, by using repeated water-immersion and restraint stress (WIRS) as a stressor for mice, we attempted to elucidate the molecular pathway induced by elevated plasma corticosterone levels. We observed the following effects both, in vivo and in vitro: (1) repeated exposure to WIRS activates the 3-phosphoinositide-dependent protein kinase (PDK1)-serum glucocorticoid regulated kinase (SGK1)-N-myc downstream-regulated gene 1 (NDRG1)-adhesion molecule (i.e., N-cadherin, a-catenin, and ß-catenin) stabilization pathway via an increase in plasma corticosterone levels; (2) the activation of this signaling pathway induces morphological changes in oligodendrocytes; and (3) after recovery from chronic stress, the abnormal arborization of oligodendrocytes and depression-like symptoms return to the control levels. Our data strongly suggest that these abnornalities of oligodendrocytes are possibly related to depression-like symptoms.

PMID:
    21655274

Appl Environ Microbiol. 2001 Aug;67(8):3440-4.
Laboratory-scale evidence for lightning-mediated gene transfer in soil.
Demanèche S, Bertolla F, Buret F, Nalin R, Sailland A, Auriol P, Vogel TM, Simonet P.
Source

Laboratoire d'Ecologie Microbienne, UMR CNRS 5557, Université Lyon I, France.
Abstract

Electrical fields and current can permeabilize bacterial membranes, allowing for the penetration of naked DNA. Given that the environment is subjected to regular thunderstorms and lightning discharges that induce enormous electrical perturbations, the possibility of natural electrotransformation of bacteria was investigated. We demonstrated with soil microcosm experiments that the transformation of added bacteria could be increased locally via lightning-mediated current injection. The incorporation of three genes coding for antibiotic resistance (plasmid pBR328) into the Escherichia coli strain DH10B recipient previously added to soil was observed only after the soil had been subjected to laboratory-scale lightning. Laboratory-scale lightning had an electrical field gradient (700 versus 600 kV m(-1)) and current density (2.5 versus 12.6 kA m(-2)) similar to those of full-scale lightning. Controls handled identically except for not being subjected to lightning produced no detectable antibiotic-resistant clones. In addition, simulated storm cloud electrical fields (in the absence of current) did not produce detectable clones (transformation detection limit, 10(-9)). Natural electrotransformation might be a mechanism involved in bacterial evolution.

PMID:
    11472916

J Mol Biol. 2008 Dec 19;384(3):564-76. Epub 2008 Oct 2.
Thioredoxin-1 and its natural inhibitor, vitamin D3 up-regulated protein 1, are differentially regulated by PPARalpha in human macrophages.
Billiet L, Furman C, Cuaz-Pérolin C, Paumelle R, Raymondjean M, Simmet T, Rouis M.
Source

UMR-7079, Université Pierre et Marie Curie/CNRS, Bâtiment A, 5ème étage/Case courrier 256, 7, Quai St-Bernard, 75252 Paris Cedex 5, France.
Abstract

Macrophage-derived reactive oxygen species contribute to the initiation and development of atherosclerosis. The cellular balance between oxidative and reductive states depends on the endogenous antioxidant capacity, with the thioredoxin-1 (Trx-1) system playing a major role. Peroxisome proliferator-activated receptor-alpha (PPARalpha) is expressed by human macrophages and exhibits anti-inflammatory properties. Here we show that the selective PPARalpha activator GW647 significantly increased the Trx-1 mRNA and protein expression in human macrophages as determined by quantitative polymerase chain reaction and Western immunoblotting. Consistently, the Trx-1 activity was significantly increased by PPARalpha activation. By contrast, PPARalpha activation led to the down-regulation of vitamin D(3) up-regulated protein 1 (VDUP-1), the physiological inhibitor of Trx-1. Analysis of the Trx-1 and VDUP-1 promoters with gene reporter assays, mutational analysis, gel shift assays and chromatin immunoprecipitation analyses revealed the presence of a functional response element specific for PPARalpha in the Trx-1 promoter and the presence of a functional activator protein 1 (AP-1) site in the VDUP-1 promoter. The interference of PPARalpha/retinoid X receptor alpha with the AP-1 transcription factor elements c-Jun/c-Fos resulted in the inhibition of AP-1 binding and down-regulation of the VDUP-1 gene expression. Finally, PPARalpha activation reduced the lidocaine-induced caspase-3 activity and apoptosis, which might be due to the VDUP-1-mediated regulation of the Bax/Bcl-2 ratio. Together these data indicate that stimulation of PPARalpha in human macrophages might reduce arterial inflammation through differential regulation of the Trx-1 and VDUP-1 gene expression.

PMID:
    18848838

Br J Pharmacol. 2007 Nov;152(5):734-43. Epub 2007 Oct 1.
Cannabinoid activation of PPAR alpha; a novel neuroprotective mechanism.
Sun Y, Alexander SP, Garle MJ, Gibson CL, Hewitt K, Murphy SP, Kendall DA, Bennett AJ.
Source

School of Biomedical Sciences, University of Nottingham Medical School, Nottingham, UK.
Abstract
BACKGROUND AND PURPOSE:

Although CB(1) receptor activation evokes neuroprotection in response to cannabinoids, some cannabinoids have been reported to be peroxisome proliferator activated receptor (PPAR) ligands, offering an alternative protective mechanism. We have, therefore, investigated the ability of a range of cannabinoids to activate PPAR alpha and for N-oleoylethanolamine (OEA), an endogenous cannabinoid-like compound (ECL), to evoke neuroprotection.
EXPERIMENTAL APPROACH:

Assays of PPAR alpha occupancy and gene transactivation potential were conducted in cell-free and transfected HeLa cell preparations, respectively. In vivo estimates of PPAR alpha activation through fat mobilization and gene transcription were conducted in mice. Neuroprotection in vivo was investigated in wild-type and PPAR alpha gene-disrupted mice.
KEY RESULTS:

The ECLs OEA, anandamide, noladin ether and virodhamine were found to bind to the purified PPAR alpha ligand binding domain and to increase PPAR alpha-driven transcriptional activity. The high affinity synthetic CB(1/2) cannabinoid agonist WIN 55212-2 bound to PPAR alpha equipotently with the PPARalpha agonist fenofibrate, and stimulated PPARalpha-mediated gene transcription. The phytocannabinoid delta 9 tetrahydrocannabinol was without effect. OEA and WIN 55212-2 induced lipolysis in vivo, while OEA pre-treatment reduced infarct volume from middle cerebral artery occlusion in wild-type, but not in PPAR alpha-null mice. OEA treatment also led to increased expression of the NFkappa B-inhibitory protein, Ikappa B, in mouse cerebral cortex, while expression of the NFkappa B-regulated protein COX-2 was inhibited. Conclusions and implications:These data demonstrate the potential for a range of cannabinoid compounds, of diverse structures, to activate PPAR alpha and suggest that at least some of the neuroprotective properties of these agents could be mediated by nuclear receptor activation.

PMID:
    17906680

Neuron. 2000 Feb;25(2):331-43.
Identification of a novel family of oligodendrocyte lineage-specific basic helix-loop-helix transcription factors.
Zhou Q, Wang S, Anderson DJ.
Source

Division of Biology, California Institute of Technology, Pasadena 91125, USA.
Abstract

Basic helix-loop-helix (bHLH) transcription factors have been identified for neurons and their precursors but not for glial cells. We have identified two bHLH factors, Oligo1 and Oligo2, that are specifically expressed in zones of neuroepithelium from which oligodendrocyte precursors emerge, as well as in the precursors themselves. Expression of Oligo2 in the spinal cord precedes that of platelet-derived growth factor receptor alpha (PDGFRalpha), the earliest known marker of oligodendrocyte precursors, by several days. Ectopic expression of Oligo2 in vivo causes ectopic expression of Sox10, an HMG-box transcription factor expressed in oligodendrocyte and other glial precursors. These data identify Oligo genes as the earliest known markers of oligodendrocyte lineage determination and suggest they play a causal role in this process.

PMID:
    10719889

Vet Microbiol. 2011 Jan 27;147(3-4):445-9. Epub 2010 Jul 16.
Serodiagnosis of sporotrichosis infection in cats by enzyme-linked immunosorbent assay using a specific antigen, SsCBF, and crude exoantigens.
Fernandes GF, Lopes-Bezerra LM, Bernardes-Engemann AR, Schubach TM, Dias MA, Pereira SA, de Camargo ZP.
Source

Universidade Federal de São Paulo, Disciplina de Biologia Celular, São Paulo, Brazil.
Abstract

The main objective of this study is to standardize an ELISA for the diagnosis of feline sporotrichosis. Sporothrix schenckii is the etiological agent of human and animal sporotrichosis. Cats may act as reservoirs for S. schenckii and can transmit the infection to humans by a bite or scratch. There are few methods for the serological diagnosis of fungal diseases in animals. In this paper, an ELISA test for the diagnosis of cat sporotrichosis is proposed, which detects S. schenckii-specific antibodies in feline sera. Two different kinds of antigens were used: "SsCBF", a specific molecule from S. schenckii that consists of a Con A-binding fraction derived from a peptido-rhamnomannan component of the cell wall, and a S. schenckii crude exoantigen preparation. The ELISA was developed, optimized, and evaluated using sera from 30 cats with proven sporotrichosis (by culture isolation); 22 sera from healthy feral cats from a zoonosis center were used as negative controls. SsCBF showed 90% sensitivity and 96% specificity in ELISA; while crude exoantigens demonstrated 96% sensitivity and 98% specificity. The ELISA assay described here would be a valuable screening tool for the detection of specific S. schenckii antibodies in cats with sporotrichosis. The assay is inexpensive, quick to perform, easy to interpret, and permits the diagnosis of feline sporotrichosis.

Copyright © 2010 Elsevier B.V. All rights reserved.

PMID:
    20708355

Pharm Biol. 2011 Sep;49(9):907-19. Epub 2011 May 19.
Subcutaneous antifungal screening of Latin American plant extracts against Sporothrix schenckii and Fonsecaea pedrosoi.
Gaitán I, Paz AM, Zacchino SA, Tamayo G, Giménez A, Pinzón R, Cáceres A, Gupta MP.
Source

Facultad de CCQQ y Farmacia, Universidad de San Carlos, Guatemala, Guatemala.
Abstract
CONTEXT:

Subcutaneous mycoses are chronic infections caused by slow growing environmental fungi. Latin American plants are used in folk medicine to treat these afflictions. Moreover, the potential of the rich Latin American biodiversity for this purpose has not been fully explored.
OBJECTIVES:

The aim of the study was to screen Latin American plant extracts against two species of subcutaneous fungi: Sporothrix schenckii and Fonsecaea pedrosoi.
MATERIALS AND METHODS:

One hundred ninety-five organic extracts from 151 Latin American plants were screened against two subcutaneous fungi by the agar dilution method at a concentration of 100 µg/mL, and minimum inhibitory concentrations (MICs) of active extracts were determined. Positive (amphothericin B) and negative (50% ethanol) controls were used.
RESULTS AND DISCUSSION:

Twenty eight extracts showed activity at =100 µg/mL. Of these, four extracts from Gnaphalium gaudichaudianum DC (Asteraceae), Plumeria rubra L (Apocynaceae), Tecoma stans (L.) Juss. ex Kunth. (Bignoniaceae), and Trichostigma octandum (L.), H. Walter showed activity against F. pedrosoi at MIC 12.5 µg/mL; and, four extracts from Bourreria huanita (Lex.) Hemsl. (Boraginaceae), Phytolacca bogotensis Kunth (Phytolaccaceae), Monnina xalapensis Kunth (Polygalaceae) and Crataegus pubescens (C. Presl) C. Presl (Rosaceae) against S. schenckii. This is the first report on antifungal activity of the Latin American plants against these two subcutaneous fungi.
CONCLUSION:

S. schenkii and F. pedrosoi were inhibited by B. huanita (MIC: 12.5 and 25 µg/mL), G. gaudichaudianum (MIC: 50 and 12.5 µg/mL) and T. triflora (MIC: 25 µg/mL).

PMID:
    21592008

Dement Geriatr Cogn Disord. 2011 Aug 26;32(2):79-93. [Epub ahead of print]
A Systematic Literature Review of Cerebrospinal Fluid Biomarkers in Delirium.
Hall RJ, Shenkin SD, Maclullich AM.
Source

Edinburgh Delirium Research Group, Geriatric Medicine, Division of Health Sciences, School of Clinical Sciences and Community Health, Edinburgh, UK.
Abstract

Background: Cerebrospinal fluid (CSF) analysis has great potential to advance understanding of delirium pathophysiology. Methods: A systematic literature review of CSF studies of DSM or ICD delirium was performed. Results: In 8 studies of 235 patients, delirium was associated with: elevated serotonin metabolites, interleukin-8, cortisol, lactate and protein, and reduced somatostatin, ß-endorphin and neuron-specific enolase. Elevated acetylcholinesterase predicted poor outcome after delirium and higher dopamine metabolites were associated with psychotic features. Conclusions: No clear conclusions emerged, but the current literature suggests multiple areas for further investigation with more detailed studies.

Copyright © 2011 S. Karger AG, Basel.

PMID:
    21876357

Int J Food Sci Nutr. 2009;60 Suppl 4:155-62.
Preliminary assessment of nutritional value of plant-based diets in relation to human nutrients.
Aberoumand A.
Source

Department of Food Science, Behbahan University, Behbehan City, Khuzestan Province, Iran. Aberoumand38@yahoo.com
Abstract

In this research, we present preliminary nutritional data for traditional vegetables and fruits including their content of mineral elements (calcium, potassium, sodium, zinc, and iron) and antioxidant phenolic compounds levels. Eight vegetables and vegetables were studied. Plant foods Asparagus officinalis DC, Chlorophytum comosum Linn., Cordia myxa Roxb., Portulaca oleracia Linn. and Solanum indicum Linn. were collected in Behbehan, south Iran, and also Alocacia indica Sch., Eulophia ocherata Lindl. and Momordica dioica Roxb. were collected from the south of India. Nutrients were measured with food analytical standard methods. The results of this study provide evidence that these local traditional vegetables, which do not require formal cultivation, could be important contributors to improving the nutritional content of Pune and Behbehan people. Results indicate that 50% of the vegetables have significant energy values ranging from 281.4 to 303.9 kcal/100 g. From this study, it was determined that five vegetables, namely A. officinalis, C. comosum, E. ocherata, P. oleracia and S. indicum, provide mineral concentrations exceeding 2% of the plant dry weight and are much higher than typical mineral concentrations in conventional edible vegetables; they are thus recommended for future commercial cultivation. High levels of antioxidant compounds were noticed in P. oleracia and S. indicum. The three plants S. indicum, A. officinalis and P. oleracia are suitable for high-temperature food processes.

PMID:
    19274594

Indian J Pharmacol. 2011 Jul;43(4):424-8.
Influence of Momordica charantia on oxidative stress-induced perturbations in brain monoamines and plasma corticosterone in albino rats.
Kavitha N, Babu SM, Rao ME.
Source

Department of Pharmacology, Roland Institute of Pharmaceutical Sciences, Berhampur, Orissa, India.
Abstract
OBJECTIVES:

The objective of this study was to evaluate the antistress activity of Momordica charantia (MC) fruit extract on stress-induced changes in albino rats and also to explore attenuating effects of MC on in vitro lipid peroxidation in rat brain.
MATERIALS AND METHODS:

In this study, Wistar albino rats (180-200 g) were used. Plasma corticosterone and monoamines-5-hydroxy tryptamine (5-HT), norepinephrine (NE), epinephrine (E) and dopamine (DA) in cortex, hypothalamus and hippocampus regions of brain were determined in animals under different stressful conditions. Ethanolic fruit extract of MC, at doses of 200 and 400 mg/kg, was used. The oxidative stress paradigms used in in vivo models were acute stress (AS) and chronic unpredictable stress (CUS). Panax quinquefolium (PQ) was used as a standard in in vivo models and ascorbic acid was used as a reference standard in the in vitro method.
RESULTS:

Subjecting the animals to AS (immobilization for 150 min once only) resulted in significant elevation of plasma corticosterone levels and brain monoamine levels. Pretreatment with MC at doses of 200 and 400 mg/kg p.o. significantly countered AS-induced changes and a similar effect was exhibited by PQ at 100 mg/kg p.o. In the CUS regimen (different stressors for 7 days), plasma corticosterone levels were significantly elevated whereas the levels of 5-HT, NE, E, and DA were depleted significantly. Pretreatment with MC (200 and 400 mg/kg) attenuated the CUS-induced changes in the levels of above monoamines in cortex, hypothalamus, and hippocampus regions of brain and plasma corticosterone in a dose-dependent manner. Furthermore, MC extract (1000-5000 µg/mL) exhibited a significant quenching effect on in vitro lipid peroxidation indicating its strong antioxidant activity which was compared with ascorbic acid.
CONCLUSIONS:

This study reveals the antistress activity of MC as it significantly reverted the stress-induced changes, and the activity might be attributed to its antioxidant activity since stress is known to involve several oxidative mechanisms.

PMID:
    21844998

Methods Mol Biol. 2009;532:163-79.
Horizontal gene transfer and the evolution of methanogenic pathways.
Fournier G.
Source

Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT, USA.
Abstract

Horizontal gene transfer (HGT) is a driving force in the evolution of metabolic pathways, allowing novel enzymatic functions that provide a selective advantage to be rapidly incorporated into an organism's physiology. Here, the role of two HGT events in the evolution of methanogenesis is described. First, the acetoclastic sub-pathway of methanogenesis is shown to have evolved via a transfer of the ackA and pta genes from a cellulolytic clostridia to a family of methanogenic archaea. Second, the system for encoding the amino acid pyrrolysine, used for the synthesis of enzymes for methanogenesis from methylamines, is shown to likely have evolved via transfer from an ancient, unknown, deeply branching organismal lineage.

PMID:
    19271184

Neurosci Lett. 2011 Jan 25;488(3):225-8. Epub 2010 Oct 12.
The effects of acupuncture (PC6) on chronic mild stress-induced memory loss.
Kim H, Park HJ, Shim HS, Han SM, Hahm DH, Lee H, Shim I.
Source

Division of Brain Disease, Center for Biomedical Science, National Institute of Health, 194 Tongillo, Eunpyeong-gu, Seoul, 122-701, Korea.
Abstract

A previous study reported that the PC6 acupuncture point can alleviate chronic mild stress (CMS)-induced anxiety [17]. Following the previous study, this study examined the effects of the PC6 acupuncture point on CMS-induced memory loss. The memory storage and acetylcholinesterase (AchE) activity in the hippocampus were measured, respectively, using a passive avoidance test (PAT) and AchE immunohistochemistry. In the PAT (retention test), the CMS group showed a markedly lower latency time than the control (post (72h): P<0.01, post (96h): P<0.05, post (120h): P<0.001). However, acupuncture at PC6 significantly recovered the impairment of memory compared to the CMS group (post (120h): P<0.001). Exposure to CMS also significantly decreased the AchE activity in the hippocampus compared to the control rats. Acupuncture stimulation at the PC6 point on the pericardium channels (3min), but not at other points (TE5), produced memory improvements and an increase in AchE reactivity in the hippocampus compared to the CMS group. These results show that the acupuncture point is effective in restoring the CMS-related biochemical and behavioral impairments, such as learning and memory.

Copyright Â© 2010 Elsevier Ireland Ltd. All rights reserved.

PMID:
    20946936

Chin Med J (Engl). 2011 Apr;124(8):1229-34.
Differential temporal neural responses of pain-related regions by acupuncture at acupoint ST36: a magnetoencephalography study.
Cheng H, Zhang XT, Yan H, Bai LJ, Ai L, Wang FB, You YB, Chen P, Wang BG.
Source

Department of Anesthesiology, Beijing Tiantan Hospital, Capital Medical University, Beijing, China.
Abstract
BACKGROUND:

Previous neuroimaging studies primarily focused on the spatial distribution of acupuncture needling stimulation. However, a salient feature of acupuncture was its long-lasting effect. This study attempted to detect the spatial-temporal neural responses evoked by acupuncture at an analgesia acupoint ST36 by using magnetoencephalography. To further verify its functional specificity, we also adopted acupuncture at Pericardium 6 and nonacupoint as separated controls.
METHODS:

Forty-two college students, all right-handed and acupuncture naïve, participated in this study. Every participant received only one acupoint stimulation, resulting in 14 subjects in one group. Both magnetoencephalography data (151-channel whole-head system) and structural functional magnetic resonance imaging data (3D sequence with a voxel size of 1 mm(3) for anatomical localization) were collected for each subject. All processing procedures were performed in BrainStorm Toolbox.
RESULTS:

Acupuncture at ST36 showed a significantly time-varied brain activities with different onset time. Our results presented that acupuncture at different acupoints (or comparing with nonacupoint) can specifically induce neural responses in different brain areas-acupuncture at ST36 can specifically induce the neural responses of pain-inhibition areas, while acupuncture at PC6 can specifically induce the activities of the insula and amygdala.
CONCLUSIONS:

In the present study, we attempted to detect the temporal neural responses underlying the functional specificity of acupuncture at ST36, using acupoint belonging to different meridians and non-acupoint with efficacy-irreverent as separate controls. The specific neural substrates involving acupuncture at different acupoints may be related to its functional specificity in clinical settings.

PMID:
    21543002

Evid Based Complement Alternat Med. 2012;2012:692621. Epub 2011 Jul 25.
Traditional chinese medicine for senile dementia.
Lin Z, Gu J, Xiu J, Mi T, Dong J, Tiwari JK.
Source

Naturals and Bioscience, Unilever R&D Shanghai, Shanghai 200233, China.
Abstract

Traditional Chinese Medicine (TCM) has a 3000 years' history of human use. A literature survey addressing traditional evidence from human studies was done, with key result that top 10 TCM herb ingredients including Poria cocos, Radix polygalae, Radix glycyrrhizae, Radix angelica sinensis, and Radix rehmanniae were prioritized for highest potential benefit to dementia intervention, related to the highest frequency of use in 236 formulae collected from 29 ancient Pharmacopoeias, ancient formula books, or historical archives on ancient renowned TCM doctors, over the past 10 centuries. Based on the history of use, there was strong clinical support that Radix polygalae is memory improving. Pharmacological investigation also indicated that all the five ingredients mentioned above can elicit memory-improving effects in vivo and in vitro via multiple mechanisms of action, covering estrogen-like, cholinergic, antioxidant, anti-inflammatory, antiapoptotic, neurogenetic, and anti-Aß activities. Furthermore, 11 active principles were identified, including sinapic acid, tenuifolin, isoliquiritigenin, liquiritigenin, glabridin, ferulic acid, Z-ligustilide, N-methyl-beta-carboline-3-carboxamide, coniferyl ferulate and 11-angeloylsenkyunolide F, and catalpol. It can be concluded that TCM has a potential for complementary and alternative role in treating senile dementia. The scientific evidence is being continuously mined to back up the traditional medical wisdom.

PMID:
    21808655

Neurosci Lett. 2011 Jun 15;497(1):22-6. Epub 2011 Apr 16.
Protective effects of catalpol on oligodendrocyte death and myelin breakdown in a rat model of chronic cerebral hypoperfusion.
Cai QY, Chen XS, Zhan XL, Yao ZX.
Source

Department of Histology and Embryology, College of Basic Medicine, The Third Military Medical University, Chongqing 400038, China.
Abstract

Chronic cerebral hypoperfusion is thought to induce white matter lesions (WMLs) with oligodendrocyte (OLG) death and myelin breakdown. Although apoptosis is believed to be involved in the pathologic process of WMLs, effective therapies for such remain lacking. In the present study, we investigated whether catalpol, an iridoid glycoside, could act on oligodendrocytes (OLGs) and myelin sheaths in a rat chronic hypoperfusion model, and whether transcription factor cAMP-responsive element binding protein (CREB) phosphorylation is involved in the resulting neuroprotection. A rat model of chronic cerebral hypoperfusion was prepared by bilateral common carotid artery ligation. On the 30th day after hypoperfusion, OLG loss and myelin disruption in the ischemic white matter were more severe and evident than in the sham control. Spatial memory was also more seriously impaired in rats after hypoperfusion. Treatment with catalpol significantly suppressed diminished OLGs and myelin breakdown, and promoted the recovery of cognitive decline. The expression of Bcl-2 and phosphorylated CREB (p-CREB) was also significantly increased by catalpol treatment. In conclusion, catalpol could protect against hypoperfusion-induced WMLs and cognitive impairment through the p-CREB signaling pathway leading to downstream upregulation of Bcl-2. Our results suggest that catalpol may be a useful approach for treating cerebrovascular WMLs.

Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

PMID:
    21524686

Zhonghua Zhong Liu Za Zhi. 2011 Apr;33(4):291-4.
[Safety and effectiveness of large dose compound Sophora flavescens Ait injection in the treatment of advanced malignant tumors].
[Article in Chinese]
Li DR, Lin HS.
Source

The Guanganmen Hospital, China Academy of Chinese Medical Sciences, Beijing 100053, China. lidaorui@sina.com
Abstract
OBJECTIVE:

To evaluate the effectiveness and safety of large dose compound Sophora flavescens Ait injection in the treatment of advanced malignant tumors.
METHODS:

A non-randomized case control trial was conducted. Ninety six patients with pathologically confirmed advanced non-small-cell lung cancer, gastric cancer and colorectal cancer were divided into traditional Chinese medicine group and chemotherapy group, 48 cases each. Patients of the traditional Chinese medicine group received treatment with large dose of compound Sophora flavescens Ait injection (20 ml/d), and 21 days as a cycle.
RESULTS:

Forty-seven patients of the traditional Chinese medicine group and 46 patients of the chemotherapy group completed their treatment, respectively. The clinical benefit rate (CBR) in the traditional Chinese medicine group was 83.0%, significantly higher than that in the chemotherapy group (69.6%) (P < 0.01). The Karnofsky performance status and weight improvement in the traditional Chinese medicine group was superior to that in the chemotherapy group (P < 0.05). Except the skin irritation in one patient in the traditional Chinese medicine group, there were no other clinical adverse effects related with the large dose compound Sophora flavescens Ait injection.
CONCLUSIONS:

Large dose compound Sophora flavescens Ait injection in the treatment of advanced malignant tumors is safe and effective. The recommended dose is 20 ml/d.

PMID:
    21575502

Scand J Med Sci Sports. 2011 Apr 21. doi: 10.1111/j.1600-0838.2011.01314.x. [Epub ahead of print]
Mitochondrial nutrients stimulate performance and mitochondrial biogenesis in exhaustively exercised rats.
Sun M, Qian F, Shen W, Tian C, Hao J, Sun L, Liu J.
Source

Key Laboratory of General Administration of Sport, Shanghai Research Institute of Sports Science, Shanghai, China State Key Laboratory of Medical Genomics, Shanghai Key Laboratory of Vascular Biology, Department of Hypertension, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China Institute for Nutritional Science, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai, China Key Laboratory of Marine Drugs, Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao, China College of Sports and Health, East China Normal University, Shanghai, China The Key Laboratory of Biomedical Information Engineering of Ministry of Education, Institute of Mitochondrial Biology and Medicine, Xi'an Jiaotong University School of Life Science and Technology, Xi'an, China.
Abstract

The aim of this study was to investigate the effects of a combination of nutrients on physical performance, oxidative stress and mitochondrial biogenesis in rats subjected to exhaustive exercise. Rats were divided into sedentary control (SC), exhaustive exercise (EC) and exhaustive exercise with nutrient supplementation (EN). The nutrients include (mg/kg/day): R-a-lipoic acid 50, acetyl-l-carnitine 100, biotin 0.1, nicotinamide 15, riboflavin 6, pyridoxine 6, creatine 50, CoQ10 5, resveratrol 5 and taurine 100. Examination of running distances over the 4-week period revealed that EN rats ran significantly longer throughout the entire duration of the exhaustive exercise period compared with the EC rats. Nutrient supplementation significantly inhibited the increase in activities of alanine transaminase, lactate dehydrogenase and creatine kinase, reversed increases in malondialdehyde, inhibited decreases in glutathione S-transferase and total antioxidant capacity in plasma, and suppressed the elevation of reactive oxygen species and apoptosis in splenic lymphocytes. Nutrient supplementation increased the protein expression of mitochondrial complexes I, II and III, mtDNA number and transcription factors involved in mitochondrial biogenesis and fusion in skeletal muscle. These findings suggest that mitochondrial nutrient supplementation can reduce exhaustive exercise-induced oxidative damage and mitochondrial dysfunction, thus leading to enhancement of physical performance and of fatigue recovery.

© 2011 John Wiley & Sons A/S.

PMID:
    21507065

J Agric Food Chem. 2011 Sep 14;59(17):9194-200. Epub 2011 Aug 5.
Konjac Glucomannan and Inulin Systematically Modulate Antioxidant Defense in Rats Fed a High-Fat Fiber-free Diet.
Wu WT, Chen HL.
Source

School of Nutrition, Chung Shan Medical University , Taichung, Taiwan.
Abstract

The aim of this study was to investigate the effects of konjac glucomannan (KGM) and inulin on the balance between pro-oxidative status and antioxidative defense systems in the colon, liver, and plasma of rats fed a high-fat fiber-free diet. Male Sprague-Dawley rats (n = 8 animals per group) were fed a high-fat (25% corn oil, w/w) fiber-free diet or that supplemented with KGM or inulin fiber (5%, w/w) for 4 weeks. The index of pro-oxidative status, malondialdehyde (MDA), and blood lymphocyte DNA damage; the antioxidative defense, that is, antioxidant enzymes (glutathione peroxidase, superoxide dismutase, catalase) in the colonic mucosa and liver; and the plasma antioxidant levels were determined. The fermentation of fiber was shown in fecal short-chain fatty acids. Incorporation of KGM and inulin into the high-fat fiber-free diet beneficially reduced the MDA levels of the colon and liver and DNA damage in blood lymphocytes. On the other hand, both fibers enhanced the antioxidative defense systems by up-regulating the gene expressions of glutathione peroxidase and catalase in the colonic mucosa and of superoxide dismutase and catalase in the liver. Furthermore, KGM and inulin promoted antioxidative status in the blood by elevating the a-tocopherol level. KGM and inulin were well-fermented in rats and increased the concentration and daily excretion of fecal short-chain fatty acids, especially acetate and butyrate. These results suggest that in vivo utilization of KGM and inulin stimulated both local and systemic antioxidative defense systems in rats.

PMID:
    21800874

J Agric Food Chem. 2011 Feb 9;59(3):989-94. Epub 2011 Jan 5.
Effects of konjac glucomannan on putative risk factors for colon carcinogenesis in rats fed a high-fat diet.
Wu WT, Chen HL.
Source

School of Nutrition, Chung Shan Medical University, Taichung, Taiwan.
Abstract

The aim of this study was to determine effects of konjac glucomannan (KGM) in a high fat corn oil diet on risk factors of colon carcinogenesis, that is, fecal ß-glucuronidase, mucinase, and bile acids, and on preventive factors, that is, fecal microflora and cecal short-chain fatty acids (SCFAs). Sprague-Dawley rats (n = 8 animals per group) were fed a normal-fat fiber-free (5% corn oil, w/w) or high-fat (25% corn oil, w/w) diet containing no fiber, KGM (5%, w/w), or inulin (5%, w/w, as a prebiotic control) for 4 weeks. Results indicated that the high-fat fiber-free diet significantly elevated the fecal ß-glucuronidase and mucinase activities and total bile acid concentration and decreased cecal SCFA contents, as compared with its normal-fat counterpart. The incorporation of KGM, as well as inulin, into the high-fat fiber-free diet beneficially reduced the fecal ß-glucuronidase and mucinase activities and lithocholic acid (secondary bile acid) concentration. Although KGM elevated the daily fecal total bile acid excretion, the change was due to the primary, instead of the secondary, bile acids. In addition, KGM beneficially promoted the daily fecal excretion of bifidobacteria and lactobacilli and cecal SCFA contents, as compared with the high-fat fiber-free diet. Therefore, the present study suggests that KGM potentially attenuated the high fat-induced risk in colon carcinogenesis.

PMID:
    21208006

Phytomedicine. 2008 Jan;15(1-2):92-7. Epub 2007 Aug 6.
Inhibitory effect of Erigeron breviscapus extract and its flavonoid components on GABA shunt enzymes.
Tao YH, Jiang DY, Xu HB, Yang XL.
Source

Institute of Materia Medica, College of Life Science and Technology, Huazhong University of Science and Technology, 430074 Wuhan, China.
Abstract

Gamma-aminobutyric acid (GABA), the major inhibitory neurotransmitter, is metabolized by the successive action of GABA transaminase (GABA-T) and succinic semialdehyde dehydrogenase (SSADH). Inhibition of both enzymes in brain tissues increases the GABA level and may have therapeutic applications in neurological diseases. Erigeron breviscapus ethanol extract was evaluated for their effect on both enzymes. This extract, its ethyl acetate fraction and aqueous fraction, significantly inhibited them at >100 microg/ml. Flavonoid components of E. breviscapus potently and noncompetitively inhibited both enzymes, and the different structure-activity relations were observed with respect to inhibition of both enzymes. Baicalein was the most potent inhibitor for GABA-T with an IC50 value of 12.8+/-1.2 microM, and scutellarein exhibited the best inhibitory effect on SSADH with an IC50 value of 7.20+/-0.9 microM. The present results may imply new pharmacological actions of E. breviscapus and contribute partially to the beneficial effect of the herb and flavonoids on the central nervous system.

PMID:
    17689232

Phytomedicine. 2011 Oct 15;18(13):1126-9. Epub 2011 May 10.
Effect of honokiol on activity of GAD(65) and GAD(67) in the cortex and hippocampus of mice.
Ku TH, Lee YJ, Wang SJ, Fan CH, Tien LT.
Source

Department of Anesthesiology, Changhua Christian Hospital, Changhua County 500, Taiwan.
Abstract

Honokiol, an active agent extracted from magnolia bark, has been reported that induces anxiolytic action in a mouse elevated plus-maze test. However, the mechanism of anxiolytic action induced by honokiol remains unclear. This study was to investigate the change in two forms of glutamic acid decarboxylase (GABA synthesized enzymes) GAD(65) and GAD(67) in the cortex and hippocampus areas while the anxiolytic actions induced by chronic administration of honokiol in mice. Mice treated with 7 daily injection of honokiol (1mg/kg, p.o.) caused anxiolytic action which was similar to that was induced by 7 daily injection of diazepam (2mg/kg, p.o.) in the elevated plus-maze test. In addition, the activity of hippocampal GAD(65) of honokiol treated mice was significantly increased than that of the vehicle or diazepam treated groups. These data suggest that honokiol causes diazepam-like anxiolytic action, which may be mediated by altering the synthesis of GABA in the brain of mice.

Copyright © 2011 Elsevier GmbH. All rights reserved.

PMID:
    21561750

Zhongguo Zhong Yao Za Zhi. 2008 Jul;33(14):1681-3.
[HPLC determination of four active components in dengzhanxixin injection].
[Article in Chinese]
Wang XM, Wang YF, Pan GX, Yang J.
Source

The Traditional Chinese Medicine Research Centre of Tianjin University of Traditional Chinese Medicine, Key Laboratory of Pharmacology of Traditional Chinese Medical Formulae, Ministry of Education, Tianjin 300193, China.
Abstract
OBJECTIVE:

To establish a method for determination of chlorogenic acid, caffeic acid, caffeoylquinic acid and ScuteIlarin in Dengzhan Xixin injection.
METHOD:

The HPLC method was carried out on Agilent Zorbax SB-C18 column (150 mm x 4. 6 mm, 5 pim) evaluated with acetonitrile-0.1% formic acid as mobile phase, gradient elution; the flow rate was 1.0 mL x min(-1); the temperatue of column was at 35 degrees C; the detection wavelength was at 335 nm for UV detection.
RESULT:

The calibration curves were linear in the range of 0.025 to 0.800 microg (r = 0.9990) for chlorogenic acid, 0.027 to 0.850 microg (r = 0.9999) for caffeic acid, 0.062 to 1.978 microg (r = 0.9997) for caffeoylquinic acid and 0.118 to 3.770 microg (r = 0.9999) for scutellarin,respectilely. The average recoveries were 97.19% with RSD 1.16%; 100.45% with RSD 1.16%; 97.32% with RSD 1.43% and 103.81% with RSD 0.70%, respectively.
CONCLUSION:

The assay demonstrated that the method was simple, it had adequate accuracy and selectivity to quantify the four active components in Dengzhan Xixin injection.

PMID:
    18841764

Zhongguo Zhong Yao Za Zhi. 2009 Jan;34(2):208-11.
[Effects of Dengzhan Xixin on blood-brain barrier permeability and metabolites after cerebral ischemia-reperfusion injuries].
[Article in Chinese]
Liu H, Liao W, Wei L, Lei H.
Source

Department of Rehabilitation Medicine, Zhongnan Hospital Wuhan University, Wuhan 430071, China.
Abstract
OBJECTIVE:

The investigated the effects of Dengzhan Xixin on brain water content, blood-brain barrier (BBB) permeability, T2-weighted imaging (T2WI), metabolites and the lesion ratio after cerebral ischemia-reperfusion injuries (IRI).
METHOD:

The 65 rats were randomly individed into three groups, the sham-operated group, the ischemia-reperfusion group and the Dengzhan Xixin treatment group. The models of ischemia-reperfusion of middle cerebral artery in rats were established by placing an intraluminal suture. The Dengzhan Xixin treatment group were injected 10% Dengzhan Xixin injection 22.5 mg kg(-1) after ischemia 1.5 h. The sh am-operated group (n=5) were sacrificed on 1 to measure brain water content and BBB permeability. The rats of the ischemia-reperfusion group (n=30) and the Dengzhan Xixin treatment group (n=30) were sacrificed at reperfusion for 6 h, 12 h, 1 d, 2 d, 4 d, 7 d, respectively, after ischemia 1.5 h. The additional 35 rats were individed into the same three groups. The changes of T2WI and metabolites in the brain were observed, and rats were sacrificed at reperfusion for 1 d, 2 d, 4 d after ischemia 1.5 h to determine the lesion ratio by TTC.
RESULT:

In the ischemia-reperfusion group, brain water content(77.93+/-0.68)% and BBB permeability (3.77+/-0.28) increased after reperfusion for 6 h. The peak time of brain water content was at 4 d (83.82+/-0.49)% and BBB permeability was at 2 d (5.51+/-0.24)%. In the ischemia-reperfusion group and the Dengzhan Xixin treatment group, there were hyperintense signals in the injury region of T2WI. In the ischemia-reperfusion group after reperfusion for 1 d, the ratio of NAA/Cr decreased and Cho/Cr increased. In the Dengzhan Xixin treatment group, the ratio of NAA/Cr increased and Cho/Cr decreased. In the treatment group, the lesion ratio decreased by TTC was 16.78+/-1.45 and in the ischemia-reperfusion group was 21.27+/-1.73 at 2 d.
CONCLUSION:

Dengzhan Xixin may relieve cerebral ischemia-reperfusion injury by influencing the metabolites of brain, stabilizing BBB and decreasing brain edema.

PMID:
    19385188

J Biol Chem. 2000 Sep 29;275(39):30677-82.
Glycosylation of GIRK1 at Asn119 and ROMK1 at Asn117 has different consequences in potassium channel function.
Pabon A, Chan KW, Sui JL, Wu X, Logothetis DE, Thornhill WB.
Source

Department of Physiology and Biophysics, Mount Sinai School of Medicine, New York, New York 10029, USA.
Abstract

GIRK (G protein-gated inward rectifier K(+) channel) proteins play critical functional roles in heart and brain physiology. Using antibodies directed to either GIRK1 or GIRK4, site-directed mutagenesis, and specific glycosidases, we have investigated the effects of glycosylation in the biosynthesis and heteromerization of these proteins expressed in oocytes. Both GIRK1 and GIRK4 have one extracellular consensus N-glycosylation site. Using chimeras between GIRK1 and GIRK4 as well as a GIRK1 N-glycosylation mutant, we report that GIRK1 was glycosylated at Asn(119), whereas GIRK4 was not glycosylated at Asn(132). GIRK1 membrane-spanning domain 1 was required for optimal glycosylation at Asn(119) because a chimera that contained GIRK4 membrane-spanning domain 1 significantly reduced the addition of a carbohydrate structure at this site. This finding may partly account for the reason that GIRK4 is not glycosylated at Asn(132), either as a homomer or when coexpressed with GIRK1. When the GIRK1(N119Q) mutant was coexpressed with GIRK4, the biophysical properties of the heteromeric channel and the magnitude of the agonist-induced currents were similar to those of controls. Thus, N-glycosylation of GIRK1 at Asn(119) does not appear to affect its physical association with GIRK4, the routing of the heteromer to the cell surface, or heteromeric channel function, unlike the dramatic functional effects of N-glycosylation of ROMK1 at Asn(117) (Schwalbe, R. A., Wang, Z., Wible, B. A., and Brown, A. M. (1995) J. Biol. Chem. 270, 15336-15340).

PMID:
    10889209

Eur J Pharmacol. 2011 Oct 1;668(1-2):133-9. Epub 2011 Jul 13.
Evaluation of the antioxidant, anti-inflammatory and hepatoprotective properties of vanillin in carbon tetrachloride-treated rats.
Makni M, Chtourou Y, Fetoui H, Garoui el M, Boudawara T, Zeghal N.
Source

; Food Processing Department, ISET, BP 377, 9100 Sidi Bouzid, Tunisia. mohamed.makni@gmail.com
Abstract

The antioxidant and anti-inflammatory effects of vanillin are considered as important forces in the protection against liver injury and fibrosis. This study investigated the protective effects of vanillin against carbon tetrachoride (CCl(4))-induced hepatotoxicity in rat. Pretreatment with vanillin prior the administration of CCl(4) significantly prevented the decrease of protein synthesis and the increase in plasma alanine (ALT) and aspartate (AST) aminotransferases. Furthermore, it inhibited hepatic lipid peroxidation (MDA) and protein carbonyl (PCO) formation and attenuated the (CCl(4))-mediated depletion of antioxidant enzyme catalase and superoxide dismutase (SOD) activities and glutathione level (GSH) in the liver. In addition, vanillin markedly attenuated the expression levels of pro-inflammatory cytokines such as tumor necrosis factor-a (TNF-a), interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) and prevented CCl(4)-induced hepatic cell alteration and necrosis, as indicated by liver histopathology. These findings suggest that the antioxidant and anti-inflammatory effects of vanillin against CCl(4)-induced acute liver injury may involve its ability to block CCl(4)-generated free radicals.

Copyright © 2011 Elsevier B.V. All rights reserved.

PMID:
    21777577

Eur J Neurosci. 2011 Sep 21. doi: 10.1111/j.1460-9568.2011.07864.x. [Epub ahead of print]
Pyruvate's blood glutamate scavenging activity contributes to the spectrum of its neuroprotective mechanisms in a rat model of stroke.
Boyko M, Zlotnik A, Gruenbaum BF, Gruenbaum SE, Ohayon S, Kuts R, Melamed I, Regev A, Shapira Y, Teichberg VI.
Source

Division of Anesthesiology and Critical Care, Soroka Medical Center, Ben-Gurion University of the Negev, 36 Hanoch Albek Str., Beer-Sheva, Israel 84833 Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA Department of Neurosurgery, Soroka Medical Center, Beer-Sheva, Israel Clinical Research Center, Soroka Medical Center, Beer-Sheva, Israel Department of Neurobiology, Weizmann Institute of Science, Rehovot, Israel.
Abstract

In previous studies, we have shown that by increasing the brain-to-blood glutamate efflux upon scavenging blood glutamate with either oxaloacetate or pyruvate, one achieves highly significant neuroprotection particularly in the context of traumatic brain injury. The current study examines, for the first time, how the blood glutamate scavenging properties of glutamate-pyruvate transaminase (GPT), alone or in combination with pyruvate, may contribute to the spectrum of its neuroprotective mechanisms and improve the outcome of rats exposed to brain ischemia, as they do after head trauma. Rats that were exposed to permanent middle cerebral artery occlusion (MCAO) and treated with intravenous 250 mg/kg pyruvate had a smaller volume of infarction and reduced brain edema, resulting in an improved neurological outcome and reduced mortality compared to control rats treated with saline. Intravenous pyruvate at the low dose of 31.3 mg/kg did not demonstrate any neuroprotection. However, when combined with 0.6 mg/kg of GPT there was a similar neuroprotection observed as seen with pyruvate at 250 mg/kg. Animals treated with 1.69 g/kg glutamate had a worse neurological outcome and a larger extent of brain edema. The decrease in mortality, infarcted brain volume and edema, as well as the improved neurological outcome following MCAO, was correlated with a decrease in blood glutamate levels. We therefore suggest that the blood glutamate scavenging activity of GPT and pyruvate contributes to the spectrum of their neuroprotective mechanisms and may serve as a new neuroprotective strategy for the treatment of ischemic stroke.

© 2011 The Authors. European Journal of Neuroscience © 2011 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

PMID:
    21936878

Prostaglandins Other Lipid Mediat. 2011 Jul 23. [Epub ahead of print]
A synaptogenic amide N-docosahexaenoylethanolamide promotes hippocampal development.
Kim HY, Spector AA, Xiong ZM.
Source

Laboratory of Molecular Signaling, National Institute of Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, MD 20892-9410, United States.
Abstract

Docosahexaenoic acid (DHA), the n-3 essential fatty acid that is highly enriched in the brain, increases neurite growth and synaptogenesis in cultured mouse fetal hippocampal neurons. These cellular effects may underlie the DHA-induced enhancement of hippocampus-dependent learning and memory functions. We found that N-docsahexaenoylethanolamide (DEA), an ethanolamide derivative of DHA, is a potent mediator for these actions. This is supported by the observation that DHA is converted to DEA by fetal mouse hippocampal neuron cultures and a hippocampal homogenate, and DEA is present endogenously in the mouse hippocampus. Furthermore, DEA stimulates neurite growth and synaptogenesis at substantially lower concentrations than DHA, and it enhances glutamatergic synaptic activities with concomitant increases in synapsin and glutamate receptor subunit expression in the hippocampal neurons. These findings suggest that DEA, an ethanolamide derivative of DHA, is a synaptogenic factor, and therefore we suggest utilizing the term 'synaptamide'. This brief review summarizes the neuronal production and actions of synaptamide and describes other N-docosahexaenoyl amides that are present in the brain.

Published by Elsevier Inc.

PMID:
    21810478

J Neurotrauma. 2011 Oct 4. [Epub ahead of print]
The Salutary Effects of DHA Dietary Supplementation on Cognition, Neuroplasticity, and Membrane Homeostasis after Brain Trauma.
Wu A, Ying Z, Gomez-Pinilla F.
Source

1 Department of Integrative Biology and Physiology, University of California at Los Angeles (UCLA) , Los Angeles, California.
Abstract

Abstract The pathology of traumatic brain injury (TBI) is characterized by the decreased capacity of neurons to metabolize energy and sustain synaptic function, likely resulting in cognitive and emotional disorders. Based on the broad nature of the pathology, we have assessed the potential of the omega-3 fatty acid docosahexaenoic acid (DHA) to counteract the effects of concussive injury on important aspects of neuronal function and cognition. Fluid percussion injury (FPI) or sham injury was performed, and rats were then maintained on a diet high in DHA (1.2% DHA) for 12 days. We found that DHA supplementation, which elevates brain DHA content, normalized levels of brain-derived neurotrophic factor (BDNF), synapsin I (Syn-1), cAMP-responsive element-binding protein (CREB), and calcium/calmodulin-dependent kinase II (CaMKII), and improved learning ability in FPI rats. It is known that BDNF facilitates synaptic transmission and learning ability by modulating Syn-I, CREB, and CaMKII signaling. The DHA diet also counteracted the FPI-reduced manganese superoxide dismutase (SOD) and Sir2 (a NAD+-dependent deacetylase). Given the involvement of SOD and Sir2 in promoting metabolic homeostasis, DHA may help the injured brain by providing resistance to oxidative stress. Furthermore, DHA normalized levels of calcium-independent phospholipase A2 (iPLA2) and syntaxin-3, which may help preserve membrane homeostasis and function after FPI. The overall results emphasize the potential of dietary DHA to counteract broad and fundamental aspects of TBI pathology that may translate into preserved cognitive capacity.

PMID:
    21851229

Biol Trace Elem Res. 2011 Sep 20. [Epub ahead of print]
Effects of Subchronic Aluminum Exposure on the Reproductive Function in Female Rats.
Wang N, She Y, Zhu Y, Zhao H, Shao B, Sun H, Hu C, Li Y.
Source

College of Veterinary Medicine, Northeast Agricultural University, Harbin, 150030, China.
Abstract

The aim of this study was to investigate the effects of aluminum (Al) exposure on the reproductive function in female rats. Forty female Wistar (5 weeks old) rats, weighing 110-120 g, were divided randomly into four groups. They were orally administrated with 0, 64.18, 128.36, and 256.72 mg aluminum chloride (AlCl(3)) per kilogram body weight in drinking water for 120 days. Levels of Al, estrogen (E(2)), progestogen (P), testosterone (T), follicle-stimulating hormone (FSH), and luteinizing hormone (LH) in serum were measured at the end of experiment. The results showed that levels of E(2), P, FSH, and LH were significantly lower and Al concentration was significantly higher in all three Al-treated groups than those in the control group (GC). The level of T was significantly higher in the low- and medium-dose groups (GL and GM) (P?<?0.05) but not in high-dose group (GH) compared with GC. The results suggest that the reproductive function of female rats is inhibited under long-term Al exposure in an Al dose-dependent manner.

PMID:
    21932046

Neuron. 2002 Nov 14;36(4):661-74.
Clathrin adaptor AP2 and NSF interact with overlapping sites of GluR2 and play distinct roles in AMPA receptor trafficking and hippocampal LTD.
Lee SH, Liu L, Wang YT, Sheng M.
Source

Picower Center for Learning and Memory, RIKEN-MIT Neuroscience Research Center, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Abstract

Proteins that bind to the cytoplasmic tails of AMPA receptors control receptor trafficking and thus the strength of postsynaptic responses. Here we show that AP2, a clathrin adaptor complex important for endocytosis, associates with a region of GluR2 that overlaps the NSF binding site. Peptides used previously to interfere with NSF binding also antagonize GluR2-AP2 interaction. Using GluR2 mutants and peptide variants that dissociate NSF and AP2 interaction, we find that AP2 is involved specifically in NMDA receptor-induced (but not ligand-dependent) internalization of AMPA receptors, and is essential for hippocampal long-term depression (LTD). NSF function, on the other hand, is needed to maintain synaptic AMPA receptor responses, but is not directly required for NMDA receptor-mediated internalization and LTD.

PMID:
    12441055

Exp Neurol. 2007 Jul;206(1):114-25. Epub 2007 Apr 24.
Time course of changes in pyridoxal 5'-phosphate (vitamin B6 active form) and its neuroprotection in experimental ischemic damage.
Hwang IK, Yoo KY, Kim do H, Lee BH, Kwon YG, Won MH.
Source

Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon 200-702, South Korea.
Abstract

In the present study, we investigated ischemia-induced changes of pyridoxal 5'-phosphate synthesizing enzyme and degrading enzyme and neuroprotective effects and roles of pyridoxal 5'-phosphate against ischemic damage in the gerbil hippocampal CA1 region. Pyridoxal 5'-phosphate oxidase and pyridoxal phosphate phosphatase immunoreactivities were changed in neurons up to 2 days after ischemia, while 4 days after ischemia their immunoreactivities were expressed in astrocytes. Pyridoxal 5'-phosphate oxidase immunoreactivity and its protein level were highest 12 h after ischemia, while those in pyridoxal phosphate phosphatase were highest 2 days after ischemia. Total activities of these enzymes were changed after ischemia, but specific activities of the enzymes were not altered. Treatment with pyridoxal 5'-phosphate into brains (4 microg/5 microl, i.c.v.) at 30 min before transient ischemia protected about 80% of CA1 pyramidal cells 4 days after ischemia and induced elevation of glutamic acid decarboxylase 67 immunoreactivity in the CA1 region. However, pyridoxal 5'-phosphate treatment into ischemic brains decreased GABA transaminase immunoreactivity in the CA1 region after ischemia. These results indicate that pyridoxal 5'-phosphate may be associated with the inhibitory discharge of GABA in the hippocampal CA1 neurons, and the increased level of GABA may protect hippocampal CA1 pyramidal cells from ischemic damage.

PMID:
    17531224

J Agric Food Chem. 2008 May 28;56(10):3532-7. Epub 2008 Apr 30.
Phytoecdysteroids increase protein synthesis in skeletal muscle cells.
Gorelick-Feldman J, Maclean D, Ilic N, Poulev A, Lila MA, Cheng D, Raskin I.
Source

Biotech Center, Cook College, Rutgers University, 59 Dudley Road, New Brunswick, New Jersey 08901, USA. jongf@eden.rutgers.edu
Abstract

Phytoecdysteroids, which are structurally similar or identical to insect molting hormones, produce a range of effects in mammals, including increasing growth and physical performance. To study the mechanism of action of phytoecdysteroids in mammalian tissue, an in vitro cellular assay of protein synthesis was developed. In C2C12 murine myotubes and human primary myotubes, phytoecdysteroids increased protein synthesis by up to 20%. In vivo, ecdysteroids increased rat grip strength. Ecdysteroid-containing plant extracts produced similar results. The effect was inhibited by a phosphoinositide kinase-3 inhibitor, which suggests a PI3K-mediated mechanism.

PMID:
    18444661

Ukr Biokhim Zh. 1992 Jul-Aug;64(4):61-7.
[Effect of phytoecdysteroids and nerobol on parameters of carbohydrate and lipid metabolism and phospholipid spectrum of liver mitochondrial membrane in experimental diabetes mellitus of rats].
[Article in Russian]
Syrov VN, Tashmukhamedova MA, Khushbaktova ZA, Mirtalipov DT, Mamatkhanov AU.
Abstract

Phytoecdysteroids: ecdysterone and turkesterone, introduced orally to male rats with the body mass 180-120 g in a dose of 5 mg/l kg of mass and nerobol in a dose of 10 mg per 1 kg of the mass for 15 days against a background of the developed alloxan diabetes cause a considerable decrease in the content of free fatty acids of the blood serum, sharply increased after the subcutaneous injection of alloxan to the animals (150 mg per 1 kg of the mass). The content of glycogen, malonic dialdehyde, pyruvic acid and calcium transporting function of the liver mitochondria are also normalized. These changes are closely interrelated (and may be mutually conditioned) with the preparation-induced reduction of phospholipid spectrum of the liver mitochondrial membranes pathologically changed owing to insulin insufficiency. In this case phytoecdysteroids in the first turn normalize the fractions of phospholipids which play the structural role in the mitochondrial membranes, and nerobol normalizes the level of minor and monoacylic phospholipids.

PMID:
    1448876

J Sep Sci. 2008 May;31(8):1387-92.
Supercritical fluid extraction of cynaropicrin and 20-hydroxyecdysone from Leuzea carthamoides DC.
Sovová H, Opletal L, Sajfrtová M, Bártlová M.
Source

Institute of Chemical Process Fundamentals, Academy ofSciences CR, Prague, Czech Republic. sovova@icpf.cas.cz
Abstract

Leuzea carthamoides is an adaptogenic plant containing biologically active compounds as ecdysteroids and guaianolide-type sesquiterpene lactones, conventionally extracted from the plant with ethanol. It may be a potential source of the mentioned natural compounds. Ethanol-modified near-critical CO(2) was used as selective solvent with the aim to increase the level of 20-hydroxyecdysone in the extract from L. carthamoides roots and to remove selectively cynaropicrin, a sesquiterpene lactone of bitter taste, from the leaves. The extraction conditions were varied (pressure 20-28 MPa, temperature 40-60 degrees C, ethanol concentration in the solvent 0-7.1%) and the extraction yield and extract composition were compared with the results of ethanolic extraction. The supercritical fluid extraction (SFE) from finely powdered plant was controlled by phase equilibrium. Cynaropicrin was quantitatively removed from the leaves where 89% of 20-hydroxyecdysone was retained. The extraction yield of 20-hydroxyecdysone from roots with ethanol-modified CO(2 )was lower by 30% than with ethanol but its concentration in the extract was higher by 67%.

PMID:
    18383243

J Ethnopharmacol. 2007 Jun 13;112(2):368-74. Epub 2007 Mar 19.
The selective effect of N-feruloylserotonins isolated from Leuzea carthamoides on nociception and anxiety in rats.
Yamamotová A, Pometlová M, Harmatha J, Rasková H, Rokyta R.
Source

Charles University, 3rd Faculty of Medicine, Department of Normal, Pathological and Clinical Physiology, Ke Karlovu 4, 120 00 Prague, Czech Republic. yamamoto@lf3.cuni.cz
Abstract

The effects of N-feruloylserotonins, substances isolated from the seeds of Leuzea carthamoides (WILLD.) DC., on nociception and anxiety were studied in Wistar rats. Nociceptive responses were measured using the plantar and tail-flick tests which were administered before and after swimming stress (3 min, water temperature 32 degrees C). Anxiety was evaluated using an elevated plus maze. In Experiment I, neither basal nociception nor stress-induced analgesia was influenced significantly. Separating the animals into groups based on their basal nociceptive sensitivity, either high- or low-pain threshold revealed that N-feruloylserotonins have selective effects, especially on rats with high-pain thresholds. In these animals, N-feruloylserotonins reduced the stress-induced analgesia that followed swimming stress. In Experiment II, basal nociceptive sensitivity correlated with indicators of anxiety; high-pain threshold rats were more anxious in the elevated plus maze, with less frequent visits to open arms. The opposite effect was seen in low-pain threshold rats. N-feruloylserotonins did not influence anxiety in low-pain threshold rats, although it reduced anxiety in the high-pain threshold rats as indicated by the increased ratio of open arm visit frequency compared to closed arm visit frequency in the elevated plus maze. From these results we concluded that N-feruloylserotonins have selective stress-reducing effects in stress-sensitive animals.

PMID:
    17442511

Reprod Domest Anim. 2011 Aug;46(4):573-8. doi: 10.1111/j.1439-0531.2010.01703.x. Epub 2010 Nov 23.
Effects of herbal preparation on libido and semen quality in boars.
Frydrychová S, Opletal L, Macáková K, Lustyková A, Rozkot M, Lipenský J.
Source

Department of Pig Breeding, Institute of Animal Science, Prague-Uhríneves, Workplace Kostelec nad Orlicí, Kostelec nad Orlicí, Czech Republic. vuzvkostelec@seznam.cz
Abstract

The objective of this study was to investigate the effects of a preparation from herbal extracts (PHE) on libido and semen quality in breeding artificial insemination boars. Ten fertile boars were divided into control and experimental groups according to significant difference of libido. There were no differences in semen quality between groups. Animals were fed a commercial feeding mixture for boars. The feeding mixture for the experimental group was enriched with PHE, which was prepared from Eurycoma longifolia, Tribulus terrestris and Leuzea carthamoides. Duration of the experiment was 10 weeks. Samples of ejaculate were collected weekly. Libido was evaluated according to a scale of 0-5 points. Semen volume, sperm motility, percentage of viable spermatozoa, sperm concentration, morphologically abnormal spermatozoa, daily sperm production and sperm survival were assessed. Amounts of mineral components and free amino acids were analysed in seminal plasma. Significant differences were found in these parameters: libido (4.05 ± 0.22 vs 3.48 ± 0.78; p < 0.001), semen volume (331.75 ± 61.91 vs 263.13 ± 87.17 g; p < 0.001), sperm concentration (386.25 ± 107.95 vs 487.25 ± 165.50 × 10(3) /mm(3); p < 0.01), morphologically abnormal spermatozoa (15.94 ± 11.08 vs 20.88 ± 9.19%; p < 0.001) and Mg concentration (28.36 ± 11.59 vs 20.27 ± 13.93 mm; p < 0.05). The experimental group's libido was increased by 20% in comparison with the beginning of the experiment. Results of this study showed positive effect of PHE on libido and some parameters of boar semen quality.

© 2010 Blackwell Verlag GmbH.

PMID:
    21092065

Genes Cells. 2001 Oct;6(10):857-68.
Two domains of Nrf2 cooperatively bind CBP, a CREB binding protein, and synergistically activate transcription.
Katoh Y, Itoh K, Yoshida E, Miyagishi M, Fukamizu A, Yamamoto M.
Source

Center for Tsukuba Advanced Research Alliance, University of Tsukuba, Japan.
Abstract
BACKGROUND:

Nrf2 belongs to the Cap-N-Collar (CNC) transcription factor family and is essential for the antioxidant responsive element (ARE)-mediated expression of a group of detoxifying and antioxidant genes. The forced expression of Nrf2 in mammalian cells activates the expression of target genes through the ARE, with Nrf2 showing the highest transactivation activity among the CNC family of transcription factors. To elucidate the molecular mechanisms generating this potent transactivation activity, we examined the functions of the domains within Nrf2.
RESULT:

We found that Nrf2 contains two transcription activation domains, Neh4 and Neh5, which act synergistically to attain maximum a activation of reporter gene expression. Neh4 and Neh5 both individually and cooperatively bind to CBP (CREB (cAMP Responsive Element Binding protein) Binding Protein). In fact, the specific inhibitor of CBP, adenovirus E1A protein, significantly reduced Nrf2 activity. Importantly, the CBP-binding activity of Nrf2 deletion mutants positively correlated with their transactivation activity. Neh5 contains a motif which is commonly conserved among the CNC factors, whereas Neh4 contains the novel CBP-interacting motif recently identified in p53 and E2F.
CONCLUSIONS:

Our results indicate that Nrf2 exploits the cooperative binding of two independent transactivation domains to CBP in the acquisition of a potent transactivation activity.

PMID:
    11683914

Biochem J. 2007 Jun 15;404(3):459-66.
Nrf2 Neh5 domain is differentially utilized in the transactivation of cytoprotective genes.
Zhang J, Hosoya T, Maruyama A, Nishikawa K, Maher JM, Ohta T, Motohashi H, Fukamizu A, Shibahara S, Itoh K, Yamamoto M.
Source

Graduate School of Comprehensive Human Sciences, Center for Tsukuba Advanced Research Alliance, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba 305-8577, Japan.
Abstract

The transcription factor Nrf2 (nuclear factor erythroid 2-related factor 2) contains two transcription activation domains, Neh4 (Nrf2 ECH homology 4) and Neh5, which co-ordinately regulate transactivation of cytoprotective genes. In the present study we aimed to clarify the role of the Neh5 domain in Nrf2-mediated gene regulation. Deletion of the complete Neh5 domain reduces expression of endogenous Nrf2 target genes, such as HO-1 (haem oxygenase 1), NQO1 [NAD(P)H:quinone oxidoreductase 1] and GCLM (glutamate cysteine ligase modulatory subunit), in human kidney epithelial cells. Furthermore, the deletion of Neh5 markedly repressed CBP [CREB (cAMP-response-element-binding protein)-binding protein] and BRG1 (Brahma-related gene 1) from associating with Nrf2, diminishing their co-operative enhancement of HO-1 promoter activity. Mutational analysis of the Neh5 domain revealed a motif that shares significant homology with beta-actin and ARP1 (actin-related protein 1). Mutagenesis of this motif selectively decreased HO-1, but not NQO1 and GCLM, expression. Taken together, these results indicate that the Neh5 domain has the ability to regulate Nrf2 target gene transcription, yet the role of the Neh5 domain in transcription varies from gene to gene.

PMID:
    17313370

J Biochem Mol Toxicol. 2008 Feb;22(1):63-76.
Phosphorylation of Nrf2 in the transcription activation domain by casein kinase 2 (CK2) is critical for the nuclear translocation and transcription activation function of Nrf2 in IMR-32 neuroblastoma cells.
Apopa PL, He X, Ma Q.
Source

Receptor Biology Laboratory, Toxicology and Molecular Biology Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Morgantown, WV 26505, USA.
Abstract

The antioxidant-activated transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) regulates the induction of cytoprotective genes against chemical toxicity and oxidative injuries. The role of phosphorylation in Nrf2 activation has been suggested but remains elusive. We report that phenolic antioxidant/pro-oxidant tert-butylhydroquinone (tBHQ) induced two forms of the Nrf2 protein in neuroblastoma cells (IMR-32), which migrated as distinctive bands on SDS-PAGE. In vitro treatment with lambda phosphatase eliminated the slower migrating form and increased the amount of the faster migrating form of Nrf2. In vivo (32)Pi-phosphorylation resulted in (32)Pi-labeling of the Nrf2 protein in the presence of tBHQ that can be dephosphorylated by lambda phosphotase, indicating that the slower migrating form is a phosphorylated Nrf2 protein and the faster form an unphosphorylated Nrf2. Unphosphorylated Nrf2 predominated in the cytoplasm, whereas the phosphorylated form preferentially localized in the nucleus. Nuclear Nrf2 can be dephosphorylated by lambda phosphotase in vitro and be converted to the faster migrating form, implicating phosphorylation of Nrf2 in the cytoplasmic-nuclear translocation of the protein. Deletional analyses from both the carboxyl- and amino-ends revealed the transcription activation (TA) domains Neh4 (Nrf2-ECH homology 4) and Neh5 (Nrf2-ECH homology 5) as a major region necessary for the phosphorylation. The TA domains are characterized by the presence of multiple phosphorylation sites of casein kinase 2 (CK2). Moreover, CK2 phosphorylated the TA domains in vitro. Treatment with CK2 inhibitor 2-dimethylamino-4,5,6,7,-tetrabromo-1H-benzimidazole (DMAT) blocked the induction of endogenous target genes of Nrf2 in cells and inhibited the TA activities of both the full length and the TA domains of Nrf2 to a large extent. Finally, phosphorylation of the TA domains correlated with the nuclear translocation of Nrf2 that was inhibited by DMAT in a concentration-dependent manner. The findings demonstrated that phosphorylation of Nrf2 at the TA domains by CK2 is an integral component of Nrf2 activation necessary for the nuclear localization and transcription activation function of Nrf2 in neuroblastoma cells.

(c) 2008 Wiley Periodicals, Inc.

PMID:
    18273910

Mol Cell Biol. 2005 May;25(10):4150-65.
Glucocorticoid receptor (GR)-associated SMRT binding to C/EBPbeta TAD and Nrf2 Neh4/5: role of SMRT recruited to GR in GSTA2 gene repression.
Ki SH, Cho IJ, Choi DW, Kim SG.
Source

College of Pharmacy, Seoul National University, Sillim-dong, Kwanak-gu, Seoul 151-742, South Korea.
Abstract

The expression of the glutathione S-transferase gene (GST), whose induction accounts for cancer chemoprevention, is regulated by activation of CCAAT/enhancer binding protein beta (C/EBPbeta) and NF-E2-related factor 2 (Nrf2). The present study investigated the repressing effects of activating glucocorticoid receptor (GR) on C/EBPbeta- and Nrf2-mediated GSTA2 gene induction and the mechanism. Dexamethasone that activates GR inhibited constitutive and oltipraz- or tert-butylhydroquinone (t-BHQ)-inducible GSTA2 expression in H4IIE cells. Also, dexamethasone repressed GSTA2 promoter-luciferase gene activity. Dexamethasone-GR activation did not inhibit nuclear translocation of C/EBPbeta or Nrf2 nor their DNA binding activities induced by oltipraz or t-BHQ. Deletion of the glucocorticoid response element (GRE) in the GSTA2 promoter abolished dexamethasone inhibition of the gene induction. Immunoprecipitation-immunoblotting, chromatin immunoprecipitation, and GST pull-down assays revealed that silencing mediator for retinoid and thyroid hormone receptors (SMRT), a corepressor recruited to steroid-GR complex for histone deacetylation, bound to TAD domain of C/EBPbeta and Neh4/5 domain of Nrf2. The GSTA2 promoter-luciferase activities were decreased by SMRT but not by truncated SMRTs. The small interference RNA (siRNA) against SMRT abolished SMRT repression of the gene induction by C/EBPbeta or Nrf2. The plasmid transfection and siRNA experiments directly evidenced the functional role of SMRT in GSTA2 repression. In conclusion, dexamethasone antagonizes C/EBPbeta- and Nrf2-mediated GSTA2 gene induction via ligand-GR binding to the GRE, and steroid-mediated GSTA2 repression involves inactivation of C/EBPbeta and Nrf2 by SMRT recruited to steroid-GR complex.

PMID:
    15870285

Antioxid Redox Signal. 2011 Apr 15;14(8):1425-36. Epub 2011 Feb 20.
Neuronal activity controls the antagonistic balance between peroxisome proliferator-activated receptor-? coactivator-1a and silencing mediator of retinoic acid and thyroid hormone receptors in regulating antioxidant defenses.
Soriano FX, Léveillé F, Papadia S, Bell KF, Puddifoot C, Hardingham GE.
Source

Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom.
Abstract

Transcriptional coactivators and corepressors often have multiple targets and can have opposing actions on transcription and downstream physiological events. The coactivator peroxisome proliferator-activated receptor-? coactivator (PGC)-1a is under-expressed in Huntington's disease and is a regulator of antioxidant defenses and mitochondrial biogenesis. We show that in primary cortical neurons, expression of PGC-1a strongly promotes resistance to excitotoxic and oxidative stress in a cell autonomous manner, whereas knockdown increases sensitivity. In contrast, the transcriptional corepressor silencing mediator of retinoic acid and thyroid hormone receptors (SMRT) specifically antagonizes PGC-1a-mediated antioxidant effects. The antagonistic balance between PGC-1a and SMRT is upset in favor of PGC-1a by synaptic activity. Synaptic activity triggers nuclear export of SMRT reliant on multiple regions of the protein. Concomitantly, synaptic activity post-translationally enhances the transactivating potential of PGC-1a in a p38-dependent manner, as well as upregulating cyclic-AMP response element binding protein-dependent PGC-1a transcription. Activity-dependent targeting of PGC-1a results in enhanced gene expression mediated by the thyroid hormone receptor, a prototypical transcription factor coactivated by PGC-1a and repressed by SMRT. As a consequence of these events, SMRT is unable to antagonize PGC-1a-mediated resistance to oxidative stress in synaptically active neurons. Thus, PGC-1a and SMRT are antagonistic regulators of neuronal vulnerability to oxidative stress. Further, this coactivator-corepressor antagonism is regulated by the activity status of the cell, with implications for neuronal viability.

PMID:
    20849372

PLoS One. 2011;6(6):e21056. Epub 2011 Jun 9.
In cortical neurons HDAC3 activity suppresses RD4-dependent SMRT export.
Soriano FX, Hardingham GE.
Source

Centre for Integrative Physiology, University of Edinburgh, Edinburgh, United Kingdom.
Abstract

The transcriptional corepressor SMRT controls neuronal responsiveness of several transcription factors and can regulate neuroprotective and neurogenic pathways. SMRT is a multi-domain protein that complexes with HDAC3 as well as being capable of interactions with HDACs 1, 4, 5 and 7. We previously showed that in rat cortical neurons, nuclear localisation of SMRT requires histone deacetylase activity: Inhibition of class I/II HDACs by treatment with trichostatin A (TSA) causes redistribution of SMRT to the cytoplasm, and potentiates the activation of SMRT-repressed nuclear receptors. Here we have sought to identify the HDAC(s) and region(s) of SMRT responsible for anchoring it in the nucleus under normal circumstances and for mediating nuclear export following HDAC inhibition. We show that in rat cortical neurons SMRT export can be triggered by treatment with the class I-preferring HDAC inhibitor valproate and the HDAC2/3-selective inhibitor apicidin, and by HDAC3 knockdown, implicating HDAC3 activity as being required to maintain SMRT in the nucleus. HDAC3 interaction with SMRT's deacetylation activation domain (DAD) is known to be important for activation of HDAC3 deacetylase function. Consistent with a role for HDAC3 activity in promoting SMRT nuclear localization, we found that inactivation of SMRT's DAD by deletion or point mutation triggered partial redistribution of SMRT to the cytoplasm. We also investigated whether other regions of SMRT were involved in mediating nuclear export following HDAC inhibition. TSA- and valproate-induced SMRT export was strongly impaired by deletion of its repression domain-4 (RD4). Furthermore, over-expression of a region of SMRT containing the RD4 region suppressed TSA-induced export of full-length SMRT. Collectively these data support a model whereby SMRT's RD4 region can recruit factors capable of mediating nuclear export of SMRT, but whose function and/or recruitment is suppressed by HDAC3 activity. Furthermore, they underline the fact that HDAC inhibitors can cause reorganization and redistribution of corepressor complexes.

PMID:
    21695276

Mol Cell Biol. 2001 Sep;21(18):6091-101.
The SMRT and N-CoR corepressors are activating cofactors for histone deacetylase 3.
Guenther MG, Barak O, Lazar MA.
Source

Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, The Penn Diabetes Center, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Abstract

Repression of gene transcription is linked to regulation of chromatin structure through deacetylation of core histone amino-terminal tails. This action is mediated by histone deacetylases (HDACs) that function within active multiprotein complexes directed to the promoters of repressed genes. In vivo, HDAC3 forms a stable complex with the SMRT corepressor. The SMRT-HDAC3 complex exhibits histone deacetylase activity, whereas recombinant HDAC3 is an inactive enzyme. Here we report that SMRT functions as an activating cofactor of HDAC3. In contrast, SMRT does not activate the class II HDAC4, with which it also interacts. Activation of HDAC3 is mediated by a deacetylase activating domain (DAD) that includes one of two SANT motifs present in SMRT. A cognate DAD is present in the related corepressor N-CoR, which can also activate HDAC3. Mutations in the DAD that abolish HDAC3 interaction also eliminate reconstitution of HDAC activity. Using purified components, the SMRT DAD is shown to be necessary and sufficient for activation of HDAC3. Moreover, the DAD is required both for HDAC3 to function enzymatically and for the major repression function of SMRT. Thus, SMRT and N-CoR do not serve merely as platforms for HDAC recruitment but function as an integral component of an active cellular HDAC3 enzyme.

PMID:
    11509652

FASEB J. 2011 May;25(5):1758-66. Epub 2011 Feb 1.
Cholesterol regulation of receptor-interacting protein 140 via microRNA-33 in inflammatory cytokine production.
Ho PC, Chang KC, Chuang YS, Wei LN.
Source

Department of Pharmacology, University of Minnesota Medical School, Minneapolis, Minnesota, 55455-0217, USA.
Abstract

Receptor interacting protein 140 (RIP140) is a nuclear receptor coregulator that affects a wide spectrum of biological processes. It is unclear whether and how the expression level of RIP140 can be modulated and whether RIP140 is involved in inflammatory diseases. Here, we examine how intracellular cholesterol regulates RIP140 expression, and we evaluate the effect of RIP140 expression on macrophage proinflammatory potential. Macrophages treated with modified low-density lipoprotein express higher RIP140 mRNA and protein levels. Consistently, simvastatin reduces RIP140 levels, which can be reversed by mevalonate. Moreover, a high-fat diet elevates RIP140 but lowers miR-33 levels in peritoneal macrophages, and increases the production of IL-1ß and TNF-a in macrophages. Mechanistically, miR-33 targets RIP140 mRNA by recognizing its target located in a highly conserved sequence of the 3'-untranslated region (3'-UTR) of RIP140 mRNA. Consequentially, miR-33 reduces RIP140 coactivator activity for NF-?B, which is supported by the reduction in NF-?B reporter activity and the inflammatory potential in macrophages. This study uncovers a cholesterol-miR-33-RIP140 regulatory pathway that modulates the proinflammatory potential in macrophages in response to an alteration in the intracellular cholesterol status, and identifies RIP140 as a direct target of miR-33 that mediates simvastatin-triggered anti-inflammation.

PMID:
    21285396

Genes Dev. 2009 Mar 15;23(6):681-93.
Cooperative NCoR/SMRT interactions establish a corepressor-based strategy for integration of inflammatory and anti-inflammatory signaling pathways.
Ghisletti S, Huang W, Jepsen K, Benner C, Hardiman G, Rosenfeld MG, Glass CK.
Source

Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093, USA.
Abstract

Innate immune responses to bacterial or viral infection require rapid transition of large cohorts of inflammatory response genes from poised/repressed to actively transcribed states, but the underlying repression/derepression mechanisms remain poorly understood. Here, we report that, while the nuclear receptor corepressor (NCoR) and silencing mediator of retinoic acid and thyroid hormone receptor (SMRT) corepressors establish repression checkpoints on broad sets of inflammatory response genes in macrophages and are required for nearly all of the transrepression activities of liver X receptors (LXRs), they can be selectively recruited via c-Jun or the Ets repressor Tel, respectively, establishing NCoR-specific, SMRT-specific, and NCoR/SMRT-dependent promoters. Unexpectedly, the binding of NCoR and SMRT to NCoR/SMRT-dependent promoters is frequently mutually dependent, establishing a requirement for both proteins for LXR transrepression and enabling inflammatory signaling pathways that selectively target NCoR or SMRT to also derepress/activate NCoR/SMRT-dependent genes. These findings reveal a combinatorial, corepressor-based strategy for integration of inflammatory and anti-inflammatory signals that play essential roles in immunity and homeostasis.

PMID:
    19299558

Nucleic Acids Res. 1998 Jun 15;26(12):2899-907.
The corepressor N-CoR and its variants RIP13a and RIP13Delta1 directly interact with the basal transcription factors TFIIB, TAFII32 and TAFII70.
Muscat GE, Burke LJ, Downes M.
Source

University of Queensland, Centre for Molecular and Cellular Biology, Ritchie Research Laboratories, B402A, St Lucia 4072, Queensland, Australia. g.guscat@cmcb.uq.edu.au
Abstract

Repression of transcription by the classical nuclear receptors (e.g. TR, RAR), the orphan nuclear receptors (e.g. Rev-erbAalpha/beta), Mxi-1 and Mad bHLH-zip proteins and the oncoproteins PLZF and LAZ3/BCL6 is mediated by the corepressors N-CoR and SMRT. The interaction of the corepressors with the components involved in chromatin remodelling, such as the recruiting proteins Sin3A/B and the histone deacteylases HDAc-1 and RPD3, has been analysed in detail. The N-CoR/Sin3/HDAc complexes have a key role in the regulation of cellular proliferation and differentiation. However, the interaction of these corepressors with the basal transcriptional machinery has remained obscure. In this study we demonstrated that the N-terminalrepression domains and the receptor interactiondomains (RID) of N-CoR and its splice variants, RIP13a and RIP13Delta1, directly interact with TAFII32 in vivo and in vitro . We show that interaction domain II within the N-CoR and RIP13a RID is required for the interaction with TAFII32. We also observed that N-CoR directly interacts with each of the basal factors, TFIIB and TAFII70, and can simultaneously interact with all three basal factors in a non-competitive manner. Furthermore, we provide evidence that suggests the RVR/Rev-erbbeta-corepressor complex also interacts with the general transcriptional machinery, and that the physicalassociation of TFIIB with N-CoR also occurs in the presence of Sin3B and HDAc-1. Interestingly, we observed that N-CoR expression ablated the functional interaction between TFIIB and TAFII32 that is critical to the initiation of transcription. In conclusion, this study demonstrates that the N-terminal repressor region and the C-terminal RIDs are part of the corepressor contact interface that mediates the interaction with the general transcription factors, and demonstrates that TAFs can also directly interact with corepressors to mediate signals from repressors to the basal machinery. We also suggest that N-CoR interacts with the central components of the transcriptional initiation process (TFIIB, TAFs) and locks them into a non-functional complex or conformation that is not conducive to transcription.

PMID:
    9611234

Biochem Soc Trans. 2000;28(4):386-9.
Modulation of thyroid hormone receptor silencing function by co-repressors and a synergizing transcription factor.
Lutz M, Baniahmad A, Renkawitz R.
Source

Genetisches Institut, Justus-Liebig-Universität, D-35392 Giessen, Germany.
Abstract

We have found that the thyroid hormone receptor (T3R) functionally synergizes with the CCCTC-binding factor (CTCF). CTCF is a highly conserved zinc-finger protein that has been connected with multiple functions in gene regulation including chromatin insulator activity, transcriptional enhancement and silencing as well as tumour suppression. A specific property of CTCF is that some of the binding sites are found in the vicinity of T3R-binding sites. Interestingly, both factors synergize in repression as well as in activation. T3R-mediated repression has been shown to involve co-repressors such as the silencing mediator for retinoic acid and thyroid hormone receptor (SMRT), N-CoR or Alien. These co-repressors in turn have been found to interact with Sin3A. Until now, the mechanisms by which CTCF synergizes with T3R in transcriptional repression has not been determined. Here we show that CTCF comprises autonomous silencing domains that mediate transcriptional repression when tethered to a promoter sequence. At least one of these domains, the zinc-finger region of CTCF, binds Sin3A without binding to SMRT or N-CoR and recruits histone deacetylation activity. For Sin3A we identified two different domains interacting independently with the CTCF zinc-finger cluster. The ability of regions of CTCF to retain deacetylase activity is correlated with the ability to bind to Sin3A and to repress transcription. Taking these results together, the synergy in repression mediated by T3R and CTCF might be achieved by the binding of multiple molecules of Sin3A to the T3R/CTCF-DNA complex, thus providing a large platform for the recruitment of histone deacetylases.

PMID:
    10961925

J Biol Chem. 2009 Jan 30;284(5):3195-210. Epub 2008 Dec 1.
The Nrf3 transcription factor is a membrane-bound glycoprotein targeted to the endoplasmic reticulum through its N-terminal homology box 1 sequence.
Zhang Y, Kobayashi A, Yamamoto M, Hayes JD.
Source

Biomedical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, UK. y.z.zhang@dundee.ac.uk
Abstract

Transcription factor Nrf3 (NF-E2 p45-related factor 3) is targeted to the endoplasmic reticulum (ER). Mouse Nrf3 is subject to proteolysis, Asn glycosylation, and deglycosylation reactions. It is synthesized as a approximately 96-kDa protein that is subsequently converted into isoforms of approximately 90, 80, and 70 kDa. In the ER, the approximately 90-kDa glycoprotein is predominant and gives rise to approximately 80- and approximately 70-kDa isoforms. The approximately 90- and approximately 80-kDa polypeptides were observed in the nuclear envelope, whereas the approximately 70-kDa isoform was detected primarily in the nucleoplasm. Our experiments showed the N-terminal homology box 1 (NHB1, residues 12-31) is part of a tripartite signal peptide sequence, comprising n, h, and c regions. The h region (residues 12-23) was demonstrated to target Nrf3 to the ER and is necessary for its Asn glycosylation. The n region (residues 1-11) controlled the abundance of the approximately 90-kDa glycoprotein. The c region (residues 24-39) was found to contain a signal peptidase cleavage site that is responsible for production of the approximately 90-kDa mature Nrf3 glycoprotein from a approximately 96-kDa precursor. We have found that Nrf3 is activated by the ER stressors tunicamycin and brefeldin A, and that NHB1 is required for this response. Amino acids between the c region and NHB2 (residues 76-100) controlled the proteolytic processing of mouse Nrf3 into cleavage products of approximately 80-kDa (glycated) and approximately 70-kDa (non-glycated); by contrast, human Nrf3 lacked a signal peptidase cleavage site between its c region and NHB2. Lastly, data are presented suggesting that the NHB2 sequence in mouse Nrf3 may regulate the topology of the transcription factor within the ER membrane.

PMID:
    19047052

Free Radic Biol Med. 2009 Jan 15;46(2):146-53. Epub 2008 Oct 9.
Oxidant stress stimulates expression of the human peroxiredoxin 6 gene by a transcriptional mechanism involving an antioxidant response element.
Chowdhury I, Mo Y, Gao L, Kazi A, Fisher AB, Feinstein SI.
Source

Institute for Environmental Medicine, University of Pennsylvania School of Medicine, 1 John Morgan Building, 3620 Hamilton Walk, Philadelphia, PA 19104-6068, USA.
Abstract

Peroxiredoxin 6 (Prdx6) is a unique antioxidant enzyme that can reduce phospholipid and other hydroperoxides. A549 cells, a human lung-derived cell line, express both Prdx6 and Nrf2, a transcription factor that binds to antioxidant-response elements (AREs) and promotes expression of antioxidant genes. Treatment of A549 cells with 500 microM H(2)O(2) increased Prdx6 mRNA levels 2.5-fold, whereas treatment with 400 microM H(2)O(2) or 200 microM tert-butylhydroquinone (t-BHQ) triggered a corresponding 2.5-fold increase in reporter gene activity in A549 cells transfected with the pSEAP2:Basic vector (BD Bioscience), containing 1524 nucleotides of the human Prdx6 promoter region. Deletion of a consensus ARE sequence present between positions 357 and 349 before the start of transcription led to a striking decrease in both basal and H(2)O(2)- or t-BHQ-induced activation in A549 cells and H(2)O(2)-induced activation in primary rat alveolar type II cells. Cotransfection with Nrf2 stimulated the Prdx6 promoter in an ARE-dependent manner, whereas it was negatively regulated by Nrf3. siRNA targeting Nrf2 down-regulated reporter gene expression, whereas siRNA targeting the Nrf2 repressor, Keap1, up-regulated it. Binding of Nrf2 to the ARE sequence in chromatin was confirmed by PCR after chromatin immunoprecipitation. These data demonstrate that the ARE within the Prdx6 promoter is a key regulator of basal transcription of the Prdx6 gene and of its inducibility under conditions of oxidative stress.

PMID:
    18973804

J Biol Chem. 2004 Dec 3;279(49):50810-7. Epub 2004 Sep 22.
Nrf3 negatively regulates antioxidant-response element-mediated expression and antioxidant induction of NAD(P)H:quinone oxidoreductase1 gene.
Sankaranarayanan K, Jaiswal AK.
Source

Department of Pharmacology, Baylor College of Medicine, Houston, Texas 77030, USA.
Abstract

Antioxidant-response element (ARE) and nuclear factor Nrf2-mediated expression and coordinated induction of genes encoding chemopreventive proteins, including NQO1, are critical mechanisms in chemoprotection. Recently, Nrf3, a new member of the Nrf family with substantial homology to Nrf2, was identified and cloned. In this report, we have investigated the role of Nrf3 in ARE-mediated gene expression and induction of NQO1 in response to antioxidants. Overexpression of Nrf3 in Hep-G2 cells led to a concentration-dependent decrease in transfected and endogenous NQO1 gene expression and induction in response to antioxidant tert-butylhydroquinone (t-BHQ). Deletion mutation analysis revealed that Nrf3 repression of NQO1 gene expression required heterodimerization and DNA binding domains but not transcriptional activation domain of Nrf3. Bandshift and supershift assays with in vitro transcribed and translated proteins and nuclear extracts from Hep-G2 cells treated with Me2SO and t-BHQ and immunoprecipitation assays demonstrated that Nrf3 associates with small Maf proteins to bind to the ARE. RNA interference specific to Nrf3 reduced intracellular Nrf3 leading to increased expression and induction of transfected and endogenous NQO1 gene expression in response to t-BHQ. These results combined suggest that Nrf3 is a negative regulator of ARE-mediated gene expression.

PMID:
    15385560

Biochem J. 2011 Aug 3. [Epub ahead of print]
Novel insights into the regulation of the antioxidant response element mediated gene expression by electrophiles: induction of the transcriptional repressor BACH1 by NRF2.
Jyrkkänen HK, Kuosmanen SM, Heinäniemi M, Laitinen H, Kansanen E, Mella-Aho E, Leinonen H, Ylä-Herttuala S, Levonen AL.
Abstract

A central mechanism in cellular defence against oxidative or electrophilic stress is mediated by transcriptional induction of genes via the Antioxidant Response Element (ARE), a cis-acting sequence present in the regulatory regions of genes involved in the detoxification and elimination of reactive oxidants and electrophiles. The ARE binds different basic-region leucine zipper (bZIP) transcription factors, most notably NF-E2 related factor-2 (Nrf2) that functions as a transcriptional activator via heterodimerization with small Maf proteins. While the ARE activation by Nrf2 is relatively well understood, the mechanisms by which ARE mediated signalling is downregulated is poorly known. Transcription factor BACH1 (BTB and CNC homology 1) binds to ARE-like sequences, functioning as a transcriptional repressor in a subset of ARE-regulated genes thus antagonizing the activator function of Nrf2. Herein, we demonstrate that BACH1 itself is regulated by Nrf2 as it is induced by Nrf2 overexpression and by Nrf2 activating agents in an Nrf2-dependent manner. Furthermore, a functional ARE site was identified at +1411 from the transcription start site of transcript variant 2 of BACH1. We conclude that BACH1 is a bona fide Nrf2 target gene, and that induction of BACH1 by Nrf2 may serve as a feedback inhibitory mechanism for ARE-mediated gene regulation.

PMID:
    21812759

J Biol Chem. 2011 Jul 1;286(26):23521-32. Epub 2011 May 9.
The BTB and CNC homology 1 (BACH1) target genes are involved in the oxidative stress response and in control of the cell cycle.
Warnatz HJ, Schmidt D, Manke T, Piccini I, Sultan M, Borodina T, Balzereit D, Wruck W, Soldatov A, Vingron M, Lehrach H, Yaspo ML.
Source

Department of Vertebrate Genomics, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany.
Abstract

The regulation of gene expression in response to environmental signals and metabolic imbalances is a key step in maintaining cellular homeostasis. BTB and CNC homology 1 (BACH1) is a heme-binding transcription factor repressing the transcription from a subset of MAF recognition elements at low intracellular heme levels. Upon heme binding, BACH1 is released from the MAF recognition elements, resulting in increased expression of antioxidant response genes. To systematically address the gene regulatory networks involving BACH1, we combined chromatin immunoprecipitation sequencing analysis of BACH1 target genes in HEK 293 cells with knockdown of BACH1 using three independent types of small interfering RNAs followed by transcriptome profiling using microarrays. The 59 BACH1 target genes identified by chromatin immunoprecipitation sequencing were found highly enriched in genes showing expression changes after BACH1 knockdown, demonstrating the impact of BACH1 repression on transcription. In addition to known and new BACH1 targets involved in heme degradation (HMOX1, FTL, FTH1, ME1, and SLC48A1) and redox regulation (GCLC, GCLM, and SLC7A11), we also discovered BACH1 target genes affecting cell cycle and apoptosis pathways (ITPR2, CALM1, SQSTM1, TFE3, EWSR1, CDK6, BCL2L11, and MAFG) as well as subcellular transport processes (CLSTN1, PSAP, MAPT, and vault RNA). The newly identified impact of BACH1 on genes involved in neurodegenerative processes and proliferation provides an interesting basis for future dissection of BACH1-mediated gene repression in neurodegeneration and virus-induced cancerogenesis.

PMID:
    21555518

Haematologica. 2010 Aug;95(8):1261-8. Epub 2010 Feb 23.
Heme controls ferroportin1 (FPN1) transcription involving Bach1, Nrf2 and a MARE/ARE sequence motif at position -7007 of the FPN1 promoter.
Marro S, Chiabrando D, Messana E, Stolte J, Turco E, Tolosano E, Muckenthaler MU.
Source

Department of Pediatric Oncology, University of Heidelberg, Im Neuenheimer Feld 153, 69120 Heidelberg, Germany.
Abstract
BACKGROUND:

Macrophages of the reticuloendothelial system play a key role in recycling iron from hemoglobin of senescent or damaged erythrocytes. Heme oxygenase 1 degrades the heme moiety and releases inorganic iron that is stored in ferritin or exported to the plasma via the iron export protein ferroportin. In the plasma, iron binds to transferrin and is made available for de novo red cell synthesis. The aim of this study was to gain insight into the regulatory mechanisms that control the transcriptional response of iron export protein ferroportin to hemoglobin in macrophages.
DESIGN AND METHODS:

Iron export protein ferroportin mRNA expression was analyzed in RAW264.7 mouse macrophages in response to hemoglobin, heme, ferric ammonium citrate or protoporphyrin treatment or to siRNA mediated knockdown or overexpression of Btb And Cnc Homology 1 or nuclear accumulation of Nuclear Factor Erythroid 2-like. Iron export protein ferroportin promoter activity was analyzed using reporter constructs that contain specific truncations of the iron export protein ferroportin promoter or mutations in a newly identified MARE/ARE element.
RESULTS:

We show that iron export protein ferroportin is transcriptionally co-regulated with heme oxygenase 1 by heme, a degradation product of hemoglobin. The protoporphyrin ring of heme is sufficient to increase iron export protein ferroportin transcriptional activity while the iron released from the heme moiety controls iron export protein ferroportin translation involving the IRE in the 5'untranslated region. Transcription of iron export protein ferroportin is inhibited by Btb and Cnc Homology 1 and activated by Nuclear Factor Erythroid 2-like involving a MARE/ARE element located at position -7007/-7016 of the iron export protein ferroportin promoter.
CONCLUSIONS:

This finding suggests that heme controls a macrophage iron recycling regulon involving Btb and Cnc Homology 1 and Nuclear Factor Erythroid 2-like to assure the coordinated degradation of heme by heme oxygenase 1, iron storage and detoxification by ferritin, and iron export by iron export protein ferroportin.
Comment in

    * Haematologica. 2010 Aug;95(8):1233-6.

PMID:
    20179090

FEBS Lett. 2009 Nov 3;583(21):3508-18. Epub 2009 Oct 12.
Prolonged cigarette smoke exposure decreases heme oxygenase-1 and alters Nrf2 and Bach1 expression in human macrophages: roles of the MAP kinases ERK(1/2) and JNK.
Goven D, Boutten A, Leçon-Malas V, Boczkowski J, Bonay M.
Source

Inserm U700, Université Paris 7, Faculté de Médecine Denis Diderot-site Bichat, Paris, France.
Abstract

Tobacco may be involved in the decreased macrophage heme oxygenase-1 (HO-1) expression described in smoking-induced severe emphysema, via the nuclear factor erythroid 2-related factor 2 (Nrf2)/Kelch-like ECH-associated protein 1 (Keap1)-BTB and CNC homology 1, basic leucine zipper transcription factor 1 (Bach1) pathway. We assessed in vitro effects of cigarette smoke condensate (CS) in the human monocyte/macrophage cell line (THP-1). CS exposure led to increased HO-1 and nuclear Nrf2 expression (6 h) followed by decreased HO-1 expression concomitantly with nuclear Nrf2/Bach1 ratio decrease (72h). CS-induced mitogen-activated protein kinase (MAPK) phosphorylation. Extracellular-signal-regulated kinase(1/2) (ERK(1/2)) and c-Jun NH2-terminal kinase (JNK) inhibition completely abrogated CS effects on HO-1 expression and nuclear Nrf2/Bach1 translocation. These results suggest that ERK(1/2) and JNK are involved in CS-induced biphasic HO-1 expression by a specific regulation of Nrf2/Keap1-Bach1.

PMID:
    19822148

Nat Struct Mol Biol. 2008 Dec;15(12):1246-54. Epub 2008 Nov 16.
Bach1 inhibits oxidative stress-induced cellular senescence by impeding p53 function on chromatin.
Dohi Y, Ikura T, Hoshikawa Y, Katoh Y, Ota K, Nakanome A, Muto A, Omura S, Ohta T, Ito A, Yoshida M, Noda T, Igarashi K.
Source

Department of Biochemistry, Tohoku University Graduate School of Medicine, Seiryo-machi 2-1, Sendai 980-8575, Japan.
Abstract

Cellular senescence is one of the key strategies to suppress expansion of cells with mutations. Senescence is induced in response to genotoxic and oxidative stress. Here we show that the transcription factor Bach1 (BTB and CNC homology 1, basic leucine zipper transcription factor 1), which inhibits oxidative stress-inducible genes, is a crucial negative regulator of oxidative stress-induced cellular senescence. Bach1-deficient murine embryonic fibroblasts showed a propensity to undergo more rapid and profound p53-dependent premature senescence than control wild-type cells in response to oxidative stress. Bach1 formed a complex that contained p53, histone deacetylase 1 and nuclear co-repressor N-coR. Bach1 was recruited to a subset of p53 target genes and contributed to impeding p53 action by promoting histone deacetylation. Because Bach1 is regulated by oxidative stress and heme, our data show that Bach1 connects oxygen metabolism and cellular senescence as a negative regulator of p53.

PMID:
    19011633

Mol Cell Biol. 1996 Nov;16(11):6083-95.
Bach proteins belong to a novel family of BTB-basic leucine zipper transcription factors that interact with MafK and regulate transcription through the NF-E2 site.
Oyake T, Itoh K, Motohashi H, Hayashi N, Hoshino H, Nishizawa M, Yamamoto M, Igarashi K.
Source

Department of Biochemistry, Tohoku University School of Medicine, Sendai, Japan.
Abstract

Members of the small Maf family (MafK, MafF, and MafG) are basic region leucine zipper (bZip) proteins that can function as transcriptional activators or repressors. The dimer compositions of their DNA binding forms determine whether the small Maf family proteins activate or repress transcription. Using a yeast two-hybrid screen with a GAL4-MafK fusion protein, we have identified two novel bZip transcription factors, Bach1 and Bach2, as heterodimerization partners of MafK. In addition to a Cap'n'collar-type bZip domain, these Bach proteins possess a BTB domain which is a protein interaction motif; Bach1 and Bach2 show significant similarity to each other in these regions but are otherwise divergent. Whereas expression of Bach1 appears ubiquitous, that of Bach2 is restricted to monocytes and neuronal cells. Bach proteins bind in vitro to NF-E2 binding sites, recognition elements for the hematopoietic transcription factor NF-E2, by forming heterodimers with MafK. Furthermore, a DNA binding complex that contained MafK as well as Bach2 or a protein related closely to Bach2 was found to be present in mouse brain cells. Bach1 and Bach2 function as transcription repressors in transfection assays using fibroblast cells, but they function as a transcriptional activator and repressor, respectively, in cultured erythroid cells. The results suggest that members of the Bach family play important roles in coordinating transcription activation and repression by MafK.

PMID:
    8887638

Am J Respir Crit Care Med. 2011 Jul 28. [Epub ahead of print]
Enhancing Nrf2 Pathway by Disruption of Keap1 in Myeloid Leukocytes Protects Against Sepsis.
Kong X, Thimmulappa R, Craciun F, Harvey C, Singh A, Kombairaju P, Reddy SP, Remick D, Biswal S.
Source

Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States.
Abstract
RATIONALE:

Sepsis syndrome is characterized by inappropriate amplified systemic inflammatory response and bacteremia that promote multiorgan failure and mortality. Nuclear factor-erythroid 2 p45-related factor 2 (Nrf2) regulates a pleiotropic cytoprotective defense program including antioxidants and protect against several inflammatory disorders by inhibiting oxidative tissue injuries. However, the role of enhanced Nrf2 activity in modulating innate immune responses to microbial infection and pathogenesis of sepsis is unclear.
OBJECTIVES:

To determine whether Nrf2 in myeloid leukocytes alter inflammatory response and protects against sepsis.
MEASUREMENTS:

Mice with deletion of Nrf2 or Keap1 in myeloid leukocyte cells and respective floxed controls were subjected to cecal ligation and puncture (CLP)-induced sepsis and were assessed for survival, organ injury, systemic inflammation and bacteremia. Using lipopolysaccharide (LPS) stimulated peritoneal macrophages, TLR4 surface trafficking and downstream signaling events were analyzed.
MAIN RESULTS:

Mortality, organ injury, circulating levels of inflammatory mediators, and bacteremia were markedly reduced in LysM-Keap1(-/-) compared to respective floxed controls (Keap1(f/f) or Nrf2(f/f)) and significantly elevated in LysM-Nrf2(-/-) mice following CLP. Peritoneal macrophages from septic LysM-Keap1(-/-) mice showed a greater bacterial phagocytic activity compared to LysM-Nrf2(-/-) and floxed controls. LPS stimulation resulted in greater reactive oxygen species-induced cell surface transport of TLR4 from trans-Golgi network and subsequent TLR4 downstream signaling (recruitment of MYD88 and TRIF, phosphorylation of IkB and IRF3, and cytokine expression) in macrophages of LysM-Nrf2(-/-) compared to LysM-Keap1(-/-) mice and floxed controls.
CONCLUSIONS:

Our study shows that Nrf2 acts as a critical immuno-modulator in leukocytes, controls host inflammatory response to bacterial infection, and protects against sepsis.

PMID:
    21799073

J Immunol. 2010 Jul 1;185(1):569-77. Epub 2010 May 28.
NADPH oxidase-dependent reactive oxygen species mediate amplified TLR4 signaling and sepsis-induced mortality in Nrf2-deficient mice.
Kong X, Thimmulappa R, Kombairaju P, Biswal S.
Source

Department of Environmental Health Sciences, Bloomberg School of Public Health, The Johns Hopkins University, Baltimore, MD 21205, USA.
Abstract

Sepsis syndrome is characterized by a dysregulated inflammatory response to infection. NADPH oxidase-dependent reactive oxygen species (ROS) play significant roles in the pathophysiology of sepsis. We previously showed that disruption of Nrf2, a master regulator of antioxidant defenses, caused a dysregulation of innate immune response that resulted in greater mortality in a polymicrobial sepsis and LPS shock model; however, the underlying mechanisms are unclear. In the current study, compared with wild-type (Nrf2(+/+)) macrophages, we observed greater protein kinase C-induced NADPH oxidase-dependent ROS generation in Nrf2-disrupted (Nrf2(-/-)) macrophages that was modulated by glutathione levels. To address the NADPH oxidase-mediated hyperinflammatory response and sepsis-induced lung injury and mortality in Nrf2(-/-) mice, we used double knockout mice lacking Nrf2 and NADPH oxidase subunit, gp91(phox) (Nrf2(-/-)//gp91(phox-/-)). Compared with Nrf2(+/+) macrophages, LPS induced greater activation of TLR4 as evident by TLR4 surface trafficking and downstream recruitment of MyD88 and Toll/IL-1R domain-containing adaptor in Nrf2(-/-) macrophages that was diminished by ablation of gp91(phox). Similarly, phosphorylation of IkappaB and IFN regulatory factor 3 as well as cytokine expression was markedly higher in Nrf2(-/-) macrophages; whereas, it was similar in Nrf2(+/+) and Nrf2(-/-)//gp91(phox-/-). In vivo studies showed greater LPS-induced pulmonary inflammation in Nrf2(-/-) mice that was significantly reduced by ablation of gp91(phox). Furthermore, LPS shock and polymicrobial sepsis induced early and greater mortality in Nrf2(-/-) mice; whereas, Nrf2(-/-)//gp91(phox-/-) showed prolonged survival. Together, these results demonstrate that Nrf2 is essential for the regulation of NADPH oxidase-dependent ROS-mediated TLR4 activation and lethal innate immune response in sepsis.

PMID:
    20511556

Am J Physiol Lung Cell Mol Physiol. 2010 Aug;299(2):L192-203. Epub 2010 May 14.
Glutaredoxin 1 regulates cigarette smoke-mediated lung inflammation through differential modulation of I{kappa}B kinases in mice: impact on histone acetylation.
Chung S, Sundar IK, Yao H, Ho YS, Rahman I.
Source

Dept. of Environmental Medicine, Univ. of Rochester Medical Center, Rochester, NY 14642, USA.
Abstract

Glutaredoxin 1 (Glrx1) is a small dithiol protein that regulates the cellular redox state and redox-dependent signaling pathways via modulation of protein glutathionylation. IkappaB kinase (IKK), an essential enzyme for NF-kappaB activation, can be subjected to S-glutathionylation leading to alteration of its activity. However, the role of Glrx1 in cigarette smoke (CS)-induced lung inflammation and chromatin modifications are not known. We hypothesized that Glrx1 regulates the CS-induced lung inflammation and chromatin modifications via differential regulation of IKKs by S-glutathionylation in mouse lung. Glrx1 knockout (KO) and wild-type (WT) mice were exposed to CS for 3 days and determined the role of Glrx1 in regulation of proinflammatory response in the lung. Neutrophil influx in bronchoalveolar lavage fluid and proinflammatory cytokine release in lung were increased in Glrx1 KO mice compared with WT mice exposed to CS, which was associated with augmented nuclear translocation of RelA/p65 and its phospho-acetylation. Interestingly, phosphorylated and total levels of IKKalpha, but not total and phosphorylated IKKbeta levels, were increased in lungs of Glrx1 KO mice compared with WT mice exposed to CS. Ablation of Glrx1 leads to increased CS-induced IKKbeta glutathionylation rendering it inactive, whereas IKKalpha was activated resulting in increased phospho-acetylation of histone H3 in mouse lung. Thus, targeted disruption of Glrx1 regulates the lung proinflammatory response via histone acetylation specifically by activation of IKKalpha in response to CS exposure. Overall, our study suggests that S-glutathionylation and phosphorylation of IKKalpha plays an important role in histone acetylation on proinflammatory gene promoters and NF-kappaB-mediated abnormal and sustained lung inflammation in pathogenesis of chronic inflammatory lung diseases.

PMID:
    20472709

Biochem Pharmacol. 2011 Aug 19. [Epub ahead of print]
Importance of PIKKs in NF-?B activation by genotoxic stress.
Sabatel H, Pirlot C, Piette J, Habraken Y.
Source

Laboratory of Immunology and Virology, GIGA-R, Building B34, Unit of Signal Transduction, University de Liège, 1 Allée de l'Hôpital, B-4000, Liège, Belgium.
Abstract

Alteration of the genome integrity leads to the activation of a vast network of cellular responses named "DNA damage response". Three kinases from the phosphoinositide 3-kinase-like protein kinase family regulate this network; ATM and DNA-PK both activated by DNA double-strand breaks and ATR activated by replication blocks. "DNA damage response" pathway coordinates cell cycle arrest, DNA repair, and the activation of transcription factors such as p53 and NF-?B. It controls senescence/apoptosis/survival of the damaged cells. Cell death or survival result from a tightly regulated balance between antagonist pro- and anti-apoptotic signals. NF-?B is a key transcription factor involved in immunity, inflammation and cell transformation. When activated by DNA double-strand breaks, NF-?B has most often a pro-survival effect and thereof interferes with chemotherapy treatments that often rely on DNA damage to induce tumor cell death (i.e. topoisomerase inhibitors and ionizing radiation). NF-?B is thus an important pharmaceutical target. Agents leading to replication stress induce a pro-apoptotic NF-?B. The molecular mechanisms initiated by DNA lesions leading to NF-?B nuclear translocation have been extensively studied these last years. In this review, we will focus on ATM, ATR and DNA-PK functions both in the IKKa/IKKß/NEMO-dependent or -independent signaling pathways and on the regulation they can exercise at the promoter level of NF-?B regulated genes.

Copyright © 2011 Elsevier Inc. All rights reserved.

PMID:
    21872579

Mol Cell. 2002 Feb;9(2):401-10.
TNF-induced recruitment and activation of the IKK complex require Cdc37 and Hsp90.
Chen G, Cao P, Goeddel DV.
Source

Tularik, Incorporated, Two Corporate Drive, South San Francisco, CA 94080, USA.
Abstract

The IKK complex, containing two catalytic subunits IKKalpha and IKKbeta and a regulatory subunit NEMO, plays central roles in signal-dependent activation of NF-kappaB. We identify Cdc37 and Hsp90 as two additional components of the IKK complex. IKKalpha/IKKbeta/NEMO and Cdc37/Hsp90 form an approximately 900 kDa heterocomplex, which is assembled via direct interactions of Cdc37 with Hsp90 and with the kinase domain of IKKalpha/IKKbeta. Geldanamycin (GA), an antitumor agent that disrupts the formation of this heterocomplex, prevents TNF-induced activation of IKK and NF-kappaB. GA treatment reduces the size of the IKK complex and abolishes TNF-dependent recruitment of the IKK complex to TNF receptor 1 (TNF-R1). Therefore, heterocomplex formation with Cdc37/Hsp90 is a prerequisite for TNF-induced activation and trafficking of IKK from the cytoplasm to the membrane.

PMID:
    11864612

PLoS One. 2011;6(8):e23488. Epub 2011 Aug 24.
NF-?B Inducing Kinase, NIK Mediates Cigarette Smoke/TNFa-Induced Histone Acetylation and Inflammation through Differential Activation of IKKs.
Chung S, Sundar IK, Hwang JW, Yull FE, Blackwell TS, Kinnula VL, Bulger M, Yao H, Rahman I.
Source

Department of Environmental Medicine, Lung Biology and Disease Program, University of Rochester Medical Center, Rochester, New York, United States of America.
Abstract
BACKGROUND:

Nuclear factor (NF)-?B inducing kinase (NIK) is a central player in the non-canonical NF ?B pathway, which phosphorylates I?B kinase a (IKKa) resulting in enhancement of target gene expression. We have recently shown that IKKa responds to a variety of stimuli including oxidants and cigarette smoke (CS) regulating the histone modification in addition to its role in NF-?B activation. However, the primary signaling mechanism linking CS-mediated oxidative stress and TNFa with histone acetylation and pro-inflammatory gene transcription is not well understood. We hypothesized that CS and TNFa increase NIK levels causing phosphorylation of IKKa, which leads to histone acetylation.
METHODOLOGY:

To test this hypothesis, we investigated whether NIK mediates effects of CS and TNFa on histone acetylation in human lung epithelial cells in vitro and in lungs of mouse exposed to CS in vivo. CS increased the phosphorylation levels of IKKa/NIK in lung epithelial cells and mouse lungs. NIK is accumulated in the nuclear compartment, and is recruited to the promoters of pro-inflammatory genes, to induce posttranslational acetylation of histones in response to CS and TNFa. Cells in which NIK is knocked down using siRNA showed partial attenuation of CSE- and TNFa-induced acetylation of histone H3 on pro-inflammatory gene promoters. Additional study to determine the role of IKKß/NF-?B pathway in CS-induced histone acetylation suggests that the canonical pathway does not play a role in histone acetylation particularly in response to CS in mouse lungs.
CONCLUSIONS:

Overall, our findings provide a novel role for NIK in CS- and TNFa-induced histone acetylation, especially on histone H3K9.

PMID:
    21887257

J Immunol. 2010 Jul 1;185(1):588-96. Epub 2010 May 26.
Nicotine inhibits Fc epsilon RI-induced cysteinyl leukotrienes and cytokine production without affecting mast cell degranulation through alpha 7/alpha 9/alpha 10-nicotinic receptors.
Mishra NC, Rir-sima-ah J, Boyd RT, Singh SP, Gundavarapu S, Langley RJ, Razani-Boroujerdi S, Sopori ML.
Source

Immunology and Asthma Division, Lovelace Respiratory Research Institute, Albuquerque, NM 87108, USA.
Abstract

Smokers are less likely to develop some inflammatory and allergic diseases. In Brown-Norway rats, nicotine inhibits several parameters of allergic asthma, including the production of Th2 cytokines and the cysteinyl leukotriene LTC(4). Cysteinyl leukotrienes are primarily produced by mast cells, and these cells play a central role in allergic asthma. Mast cells express a high-affinity receptor for IgE (FcepsilonRI). Following its cross-linking, cells degranulate and release preformed inflammatory mediators (early phase) and synthesize and secrete cytokines/chemokines and leukotrienes (late phase). The mechanism by which nicotine modulates mast cell activation is unclear. Using alpha-bungarotoxin binding and quantitative PCR and PCR product sequencing, we showed that the rat mast/basophil cell line RBL-2H3 expresses nicotinic acetylcholine receptors (nAChRs) alpha7, alpha9, and alpha10; exposure to exceedingly low concentrations of nicotine (nanomolar), but not the biologically inactive metabolite cotinine, for > or = 8 h suppressed the late phase (leukotriene/cytokine production) but not degranulation (histamine and hexosaminidase release). These effects were unrelated to those of nicotine on intracellular free calcium concentration but were causally associated with the inhibition of cytosolic phospholipase A(2) activity and the PI3K/ERK/NF-kappaB pathway, including phosphorylation of Akt and ERK and nuclear translocation of NF-kappaB. The suppressive effect of nicotine on the late-phase response was blocked by the alpha7/alpha9-nAChR antagonists methyllycaconitine and alpha-bungarotoxin, as well as by small interfering RNA knockdown of alpha7-, alpha9-, or alpha10-nAChRs, suggesting a functional interaction between alpha7-, alpha9-, and alpha10-nAChRs that might explain the response of RBL cells to nanomolar concentrations of nicotine. This "hybrid" receptor might serve as a target for novel antiallergic/antiasthmatic therapies.

PMID:
    20505147

Psychopharmacology (Berl). 2004 Apr;172(4):375-83. Epub 2004 Jan 15.
AR-R 17779 improves social recognition in rats by activation of nicotinic alpha7 receptors.
Van Kampen M, Selbach K, Schneider R, Schiegel E, Boess F, Schreiber R.
Source

CNS Research, Bayer AG, 42096 Wuppertal, Germany.
Abstract
RATIONALE:

Nicotine and agonists at alpha(4)beta(2) and alpha(7) nicotinic acetylcholine receptors (nAChRs) improve learning and memory. The alpha(7)-nAChR subtype is of special interest, since it appears to play no role in the abuse liability of nicotine.
OBJECTIVES AND METHODS:

To further investigate the role of the alpha(7)-nAChR in learning and memory, the effects of the specific alpha(7)-nAChR agonist AR-R17779 on cognition were measured in the rat social recognition test (SRT) and the effect of the alpha(7)-nAChR antagonist methyllycaconitine (MLA) was studied. The SRT and a scopolamine-induced deficit version were validated with the acetylcholinesterase inhibitor metrifonate. Social memory was measured by the ability of an adult rat to recognize a juvenile rat after a delay. The difference in social interaction time (SIT) was measured between two encounters. The difference in SIT is expressed as percent reduction in social interaction time (%RSIT).
RESULTS:

Metrifonate (10 and 30 mg/kg PO) increased %RSIT in a behaviorally specific manner, employing a 24-h interval and reversed the scopolamine-induced deficit at a retention time of 15 min. Likewise, AR-R17779 increased %RSIT in unimpaired animals (1, 3, 10 and 30 mg/kg SC) employing a 24-h retention interval, and reversed the scopolamine-induced deficit (0.3 and 1 mg/kg SC) after a 15-min retention interval. The effects of AR-R17779 (1 mg/kg SC) in unimpaired animals were reversed by MLA (10 micro g ICV), which induced a decrease of %RSI at a 15-min retention interval when given alone.
CONCLUSIONS:

AR-R17779 increased social recognition memory by activation of alpha(7)-nAChRs, suggesting that alpha(7)-nAChR agonists possess cognitive-enhancing properties.

PMID:
    14727003

Behav Pharmacol. 1999 Nov;10(6-7):675-80.
AR-R17779, and alpha7 nicotinic agonist, improves learning and memory in rats.
Levin ED, Bettegowda C, Blosser J, Gordon J.
Source

Psychiatry Department, Duke University Medical Center, Durham, North Carolina 27710, USA. edlevin@duke.edu
Abstract

Nicotinic acetylcholine systems have been found to be important for learning and memory function. The prototypic nicotinic agonist nicotine has been shown in a variety of studies to improve aspects of cognitive function. The specific involvement of nicotinic receptor subtypes is now being investigated. The involvement of alpha7 nicotinic receptors was assessed in this project using a novel alpha7 nicotinic agonist, AR-R 17779. Repeated doses (subcutaneous injection 20 min before testing) of the racemic mixture AR-R 13489 and its active isomer AR-R 17779 were assessed in adult female Sprague-Dawley rats using the eight-arm radial maze. AR-R 13489 (2 mg/kg) caused a significant improvement of long-term win-shift acquisition after 3 weeks of training (n = 10 per group). The same dose of AR-R 17779 also caused a significant improvement in repeated acquisition within each daily session in the radial-arm maze. In another study, the active isomer AR-R 17779 significantly improved radial-arm maze working memory function in rats with lesions to the septohippocampal projection. Fimbria-fornix lesions significantly impaired working memory performance and AR-R 17779 significantly reversed that impairment. These studies showed that alpha7 nicotinic agonist treatment improved learning in two radial-arm maze tasks and reversed working memory impairment caused by fimbria-fornix sections, providing evidence for alpha7 involvement in learning and memory, and the potential therapeutic use of AR-R 17779.

PMID:
    10780509

J Clin Endocrinol Metab. 1978 Dec;47(6):1348-51.
Stimulation of prolactin and growth hormone secretion by muscimol, a gamma-aminobutyric acid agonist.
Tamminga CA, Neophytides A, Chase TN, Frohman LA.
Abstract

The alteration in circulating levels of PRL, GH, TSH, and cortisol was studied after the oral administration of muscimol (3-hydroxy-5-aminomethylisoxazole) to human subjects with Huntington's disease (n = 4) and chronic schizophrenia (n = 5). PRL levels rose significantly in a dose-dependent fashion within a 120-min time interval. GH rose significantly but modestly over the same time interval, whereas TSH and cortisol levels remained unchanged. Since muscimol is thought to be a potent and specific gamma-aminobutyric acid agonist, these data indicate that gamma-aminobutyric acid-mediated neural transmission may function to stimulate the release of plasma PRL and GH in human subjects.

PMID:
    162520

Neuropsychopharmacology. 2010 Mar;35(4):999-1007. Epub 2009 Dec 23.
Prototypic GABA(A) receptor agonist muscimol acts preferentially through forebrain high-affinity binding sites.
Chandra D, Halonen LM, Linden AM, Procaccini C, Hellsten K, Homanics GE, Korpi ER.
Source

Departments of Anesthesiology and Pharmacology & Chemical Biology, University of Pittsburgh, Pittsburgh, PA, USA.
Abstract

Muscimol has been regarded as a universal agonist for all gamma-aminobutyric acid type A receptor (GABA(A)-R) subtypes. However, brain regional distribution of muscimol's high-affinity binding sites greatly differs from those of other binding sites of the GABA(A)-R. To test whether behavioral effects of muscimol correlated with the density of high-affinity [(3)H]muscimol binding, we examined several GABA(A)-R subunit gene-modified mouse lines: alpha1, alpha4, or delta-knockouts (KO), alpha4+delta-double KO, and Thy1.2 promoter-driven alpha6 transgenic mice (Thy1alpha6). We determined the high-affinity [(3)H]muscimol binding in brain sections by quantitative autoradiography and sedative/ataxic effects induced in vivo by muscimol using a constant speed rotarod. alpha4-KO mice had reduced [(3)H]muscimol binding in the caudate-putamen, thalamus, and hippocampus, and were less sensitive to the behavioral impairment by muscimol. Similarly, delta-KO mice also had reduced binding to forebrain regions and a lower behavioral sensitivity to muscimol than their wild-type controls. In contrast, alpha1-KO mice had unaltered behavioral sensitivity to muscimol and unaltered [(3)H]muscimol binding, even though previous studies have demonstrated dramatically reduced binding to various other GABA(A)-R sites in these mice. Finally, Thy1alpha6 mice exhibited increased behavioral sensitivity to muscimol, and to another direct GABA-site agonist gaboxadol, and increased [(3)H]muscimol binding in the cerebral cortex and hippocampus. Thus, the differences in sedative and motor-impairing actions of muscimol in various mouse models correlated with the level of forebrain high-affinity [(3)H]muscimol binding. These data suggest that a small special population of GABA(A)-Rs, most likely extrasynaptic non-alpha1-containing receptors, strongly contributes to the in vivo pharmacological effects of muscimol.

PMID:
    20032968

DNA Cell Biol. 2011 Jul 20. [Epub ahead of print]
Regulation of Insulin Gene Transcription by Multiple Histone Acetyltransferases.
Sampley ML, Ozcan S.
Source

Department of Molecular and Cellular Biochemistry, College of Medicine, University of Kentucky , Lexington, Kentucky.
Abstract

Glucose-stimulated insulin gene transcription is mainly regulated by a 340-bp promoter region upstream of the transcription start site by beta-cell-enriched transcription factors Pdx-1, MafA, and NeuroD1. Previous studies have shown that histone H4 hyperacetylation is important for acute up-regulation of insulin gene transcription. Until now, only the histone acetyltransferase (HAT) protein p300 has been shown to be involved in this histone H4 acetylation event. In this report we investigated the role of the additional HAT proteins CREB binding protein (CBP), p300/CBP-associated factor (PCAF), and general control of amino-acid synthesis 5 (GCN5) in regulation of glucose-stimulated insulin gene transcription. Utilizing quantitative chromatin immunoprecipitation analysis, we demonstrate that glucose regulates the binding of p300, CBP, PCAF, and GCN5 to the proximal insulin promoter. siRNA-mediated knockdown of each of these HAT proteins revealed that depletion of p300 and CBP leads to a drastic decrease in histone H4 acetylation at the insulin promoter and in insulin gene expression, whereas knockdown of PCAF and GCN5 leads to a more moderate decrease in histone H4 acetylation and insulin gene expression. These data suggest that high glucose mediates the recruitment of p300, CBP, PCAF, and GCN5 to the insulin promoter and that all four HATs are important for insulin gene expression.

PMID:
    21774670

Expert Opin Ther Pat. 2011 Oct;21(10):1651-6. Epub 2011 Jul 15.
Epigenetic modulation of PGC-1a activity by GCN5 inhibitors: WO2010007085.
Carradori S, Secci D, Mai A.
Source

Istituto Pasteur-Fondazione Cenci Bolognetti, Dipartimento di Chimica e Tecnologie del Farmaco , Sapienza University of Rome, P.le A. Moro 5, 00185 Rome , Italy +0039 06 4991 3392 ; +0039 06 4969 3268 ; antonello.mai@uniroma1.it.
Abstract

The transcriptional peroxisome proliferator-activated receptor ? (PPAR?) co-activator PGC-1a plays a central role in the regulation of cellular energy metabolism. Among the wide range of its activities, PGC-1a controls mitochondrial biogenesis and function and is one of the main factors involved in hormonal and nutrient regulation of hepatic gluconeogenesis. PGC-1a is present in a multiprotein complex, and its activity can also be modulated through epigenetic modifications. In particular, it is directly acetylated by the HAT enzyme general control nonderepressible 5 (GCN5), resulting in a transcriptionally inactive protein that relocalizes from promoter regions to nuclear foci, whereas it is deacetylated by SIRT1 at multiple lysine sites, with a subsequent increase in its activity leading to induction of liver gluconeogenic gene transcription. Thus, both GCN5 and SIRT1 may be pharmacological targets to regulate the activity of PGC-1a, providing a potential treatment for metabolic disorders in which hepatic glucose output is altered.

PMID:
    21756203

Oncogene. 2011 Jul 4. doi: 10.1038/onc.2011.261. [Epub ahead of print]
And-1 is required for the stability of histone acetyltransferase Gcn5.
Li Y, Jaramillo-Lambert AN, Yang Y, Williams R, Lee NH, Zhu W.
Source

Department of Biochemistry and Molecular Biology, The George Washington University Medical School, Washington, DC, USA.
Abstract

Histone acetyltransferases (HATs) have a central role in the modification of chromatin as well as in the pathogenesis of a broad set of diseases including cancers. Gcn5 is the first identified transcription-related HAT that has been implicated in the regulation of diverse cellular functions. However, how Gcn5 proteins are regulated remains largely unknown. Here we show that acidic nucleoplasmic DNA-binding protein (And-1, a high mobility group domain-containing protein) has remarkable capability to regulate the stability of Gcn5 proteins and thereby histone H3 acetylation. We find that And-1 forms a complex with both histone H3 and Gcn5. Downregulation of And-1 results in Gcn5 degradation, leading to the reduction of H3K9 and H3K56 acetylation. And-1 overexpression stabilizes Gcn5 through protein-protein interactions in vivo. Furthermore, And-1 expression is increased in cancer cells in a manner correlating with increased Gcn5 and H3K9Ac and H3K56Ac. Thus, our data reveal not only a functional link between Gcn5 and And-1 that is essential for Gcn5 protein stability and histone H3 acetylation, but also a potential role of And-1 in cancer.Oncogene advance online publication, 4 July 2011; doi:10.1038/onc.2011.261.

PMID:
    21725360

J Cell Sci. 1997 May;110 ( Pt 9):1051-62.
AND-1, a natural chimeric DNA-binding protein, combines an HMG-box with regulatory WD-repeats.
Köhler A, Schmidt-Zachmann MS, Franke WW.
Source

Division of Cell Biology, German Cancer Research Center, Heidelberg, Germany.
Abstract

Using a specific monoclonal antibody (mAb AND-1/23-5-14) we have identified, cDNA-cloned and characterized a novel DNA-binding protein of the clawed toad, Xenopus laevis, that is accumulated in the nucleoplasm of oocytes and various other cells. This protein comprises 1,127 amino acids, with a total molecular mass of 125 kDa and a pI of 5.27. It is encoded by a mRNA of approximately 4 kb and contains, in addition to clusters of acidic amino acids, two hallmark motifs: the amino-terminal part harbours seven consecutive 'WD-repeats', which are sequence motifs of about 40 amino acids that are characteristic of a large group of regulatory proteins involved in diverse cellular functions, while the carboxy terminal portion possesses a 63-amino-acid-long 'HMG-box', which is typical of a family of DNA-binding proteins involved in regulation of chromatin assembly, transcription and replication. The DNA-binding capability of the protein was demonstrated by DNA affinity chromatography and electrophoretic mobility shift assays using four-way junction DNA. Protein AND-1 (acidic nucleoplasmic DNA-binding protein) appears as an oligomer, probably a homodimer, and has been localized throughout the entire interchromatinic space of the interphase nucleoplasm, whereas during mitosis it is transiently dispersed over the cytoplasm. We also identified a closely related, perhaps orthologous protein in mammals. The unique features of protein AND-1, which is a 'natural chimera' combining properties of the WD-repeat and the HMG-box families of proteins, are discussed in relation to its possible nuclear functions.

PMID:
    9175701

J Biol Chem. 2010 Mar 26;285(13):9493-505. Epub 2010 Jan 19.
Influence of the human cohesion establishment factor Ctf4/AND-1 on DNA replication.
Bermudez VP, Farina A, Tappin I, Hurwitz J.
Source

Program of Molecular Biology, Memorial Sloan-Kettering Cancer Center, New York, New York 10065, USA.
Abstract

Ctf4/AND-1 is a highly conserved gene product required for both DNA replication and the establishment of sister chromatid cohesion. In this report, we examined the mechanism of action of human Ctf4 (hCtf4) in DNA replication both in vitro and in vivo. Our findings show that the purified hCtf4 exists as a dimer and that the hCtf4 SepB domain likely plays a primary role determining the dimeric structure. hCtf4 binds preferentially to DNA template-primer structures, interacts directly with the replicative DNA polymerases (alpha, delta, and epsilon), and markedly stimulates the polymerase activities of DNA polymerases alpha and epsilon in vitro. Depletion of hCtf4 in HeLa cells by small interfering RNA resulted in G(1)/S phase arrest. DNA fiber analysis revealed that cells depleted of hCtf4 exhibited a rate of DNA replication slower than cells treated with control small interfering RNA. These findings suggest that in human cells, hCtf4 plays an essential role in DNA replication and its ability to stimulate the replicative DNA polymerases may contribute to this effect.

PMID:
    20089864

Genes Cells. 2009 Jul;14(7):807-20. Epub 2009 Jun 3.
Ctf4 coordinates the progression of helicase and DNA polymerase alpha.
Tanaka H, Katou Y, Yagura M, Saitoh K, Itoh T, Araki H, Bando M, Shirahige K.
Source

Laboratory of Chromosome Structure and Function, Department of Biological Science, Graduate School of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama City, Kanagawa, Japan.
Abstract

Ctf4 is a protein conserved in eukaryotes and a constituent of the replisome progression complex. It also plays a role in the establishment of sister chromatid cohesion. In our current study, we demonstrate that the replication checkpoint is activated in the absence of Ctf4, and that the interaction between the MCM helicase-go ichi ni san (GINS) complex and DNA polymerase alpha (Pol alpha)-primase is destabilized specifically in a ctf4Delta mutant. An in vitro interaction between GINS and DNA Pol alpha was also found to be mediated by Ctf4. The same interaction was not affected in the absence of the replication checkpoint mediators Tof1 or Mrc1. In ctf4Delta cells, DNA pol alpha became significantly unstable and was barely detectable at the replication forks in HU. In contrast, the quantities of helicase and DNA pol epsilon bound to replication forks were almost unchanged but their localizations were widely and abnormally dispersed in the mutant cells compared with wild type. These results lead us to propose that Ctf4 is a key connector between DNA helicase and Pol alpha and is required for the coordinated progression of the replisome.

PMID:
    19496828

J Neurochem. 2009 Feb;108(3):676-84. Epub 2008 Nov 28.
Hydrogen sulfide evokes neurite outgrowth and expression of high-voltage-activated Ca2+ currents in NG108-15 cells: involvement of T-type Ca2+ channels.
Nagasawa K, Tarui T, Yoshida S, Sekiguchi F, Matsunami M, Ohi A, Fukami K, Ichida S, Nishikawa H, Kawabata A.
Source

Division of Pharmacology and Pathophysiology, Kinki University School of Pharmacy, Higashi-Osaka, Japan.
Abstract

We investigated if stimulation of T-type Ca(2+) channels with sodium hydrosulfide (NaHS), a donor of hydrogen sulfide (H(2)S), could cause neuronal differentiation of NG108-15 cells. Like dibutyryl cyclic AMP (db-cAMP), treatment with NaHS at 1.5-13.5 mM for 16 h enhanced neurite outgrowth in a concentration-dependent manner. Synergistic neuritogenic effect was obtained in the cells stimulated with NaHS in combination with db-cAMP at subeffective concentrations. Exposure to NaHS or db-cAMP for 2 days resulted in enhancement of expression of high-voltage-activated currents consisting of N-, P/Q-, L- and also other types, but not of T-type currents. Mibefradil, a pan-T-type channel blocker, abolished the neuritogenesis induced by NaHS, but not by db-cAMP. The NaHS-evoked neuritogenesis was also completely blocked by pretreatment with BAPTA/AM, a chelator of intracellular Ca(2+), and by zinc chloride at a concentration known to selectively inhibit Ca(v)3.2 isoform of T-type Ca(2+) channels, but not Ca(v)3.1 or Ca(v)3.3. Further, L-ascorbate, recently proven to selectively inhibit Ca(v)3.2, abolished the neuritogenic effect of NaHS, but not db-cAMP. Our data thus demonstrate that NaHS/H(2)S is a novel inducer of neuronal differentiation in NG108-15 cells, as characterized by neuritogenesis and expression of high-voltage-activated currents, and suggest the involvement of T-type Ca(2+) channels, especially Ca(v)3.2.

PMID:
    19054275

Proc Natl Acad Sci U S A. 2011 Aug 16;108(33):13823-8. Epub 2011 Aug 1.
The Ca(V)3.3 calcium channel is the major sleep spindle pacemaker in thalamus.
Astori S, Wimmer RD, Prosser HM, Corti C, Corsi M, Liaudet N, Volterra A, Franken P, Adelman JP, Lüthi A.
Source

Department of Cell Biology and Morphology, University of Lausanne, CH-1005 Lausanne, Switzerland.
Abstract

Low-threshold (T-type) Ca(2+) channels encoded by the Ca(V)3 genes endow neurons with oscillatory properties that underlie slow waves characteristic of the non-rapid eye movement (NREM) sleep EEG. Three Ca(V)3 channel subtypes are expressed in the thalamocortical (TC) system, but their respective roles for the sleep EEG are unclear. Ca(V)3.3 protein is expressed abundantly in the nucleus reticularis thalami (nRt), an essential oscillatory burst generator. We report the characterization of a transgenic Ca(V)3.3(-/-) mouse line and demonstrate that Ca(V)3.3 channels are indispensable for nRt function and for sleep spindles, a hallmark of natural sleep. The absence of Ca(V)3.3 channels prevented oscillatory bursting in the low-frequency (4-10 Hz) range in nRt cells but spared tonic discharge. In contrast, adjacent TC neurons expressing Ca(V)3.1 channels retained low-threshold bursts. Nevertheless, the generation of synchronized thalamic network oscillations underlying sleep-spindle waves was weakened markedly because of the reduced inhibition of TC neurons via nRt cells. T currents in Ca(V)3.3(-/-) mice were <30% compared with those in WT mice, and the remaining current, carried by Ca(V)3.2 channels, generated dendritic [Ca(2+)](i) signals insufficient to provoke oscillatory bursting that arises from interplay with Ca(2+)-dependent small conductance-type 2 K(+) channels. Finally, naturally sleeping Ca(V)3.3(-/-) mice showed a selective reduction in the power density of the s frequency band (10-12 Hz) at transitions from NREM to REM sleep, with other EEG waves remaining unaltered. Together, these data identify a central role for Ca(V)3.3 channels in the rhythmogenic properties of the sleep-spindle generator and provide a molecular target to elucidate the roles of sleep spindles for brain function and development.

PMID:
    21808016

Neuroscientist. 2002 Aug;8(4):335-46.
Two phylogenetic specializations in the human brain.
Allman J, Hakeem A, Watson K.
Source

Division of Biology, California Institute of Technology, Pasadena, California 91125, USA. cebus@caltech.edu
Abstract

In this study, two anatomical specializations of the brain in apes and humans are considered. One of these is a whole cortical area located in the frontal polar cortex (Brodmann's area 10), and the other is a morphologically distinctive cell type, the spindle neuron of the anterior cingulate cortex. The authors suggest that the spindle cells may relay to other parts of the brain--especially to area 10, the outcome of processing within the anterior cingulate cortex. This relay conveys the motivation to act. It particularly concerns the recognition of having committed an error that leads to the initiation of adaptive responses to these adverse events so as to reduce error commission. This capacity is related to the development of self-control as an individual matures and gains social insight. Although the anterior cingulate deals with the individual's immediate response to changing conditions, area 10 is involved in the retrieval of memories from the individual's past experience and the capacity to plan adaptive responses. The authors suggest that these neurobehavioral specializations are crucial aspects of intelligence as defined as the capacity to make adaptive responses to changing conditions. The authors further hypothesize that these specializations facilitated the evolution of the unique capacity for the intergenerational transfer of the food and information characteristic of human extended families.

PMID:
    12194502

Am J Psychiatry. 2011 Jul;168(7):727-34. Epub 2011 Apr 15.
Reduced metabotropic glutamate receptor 5 density in major depression determined by [(11)C]ABP688 PET and postmortem study.
Deschwanden A, Karolewicz B, Feyissa AM, Treyer V, Ametamey SM, Johayem A, Burger C, Auberson YP, Sovago J, Stockmeier CA, Buck A, Hasler G.
Source

PET Center, Division of Nuclear Medicine, University Hospital, Zurich.
Abstract
OBJECTIVE:

Clinical and preclinical evidence suggests a hyperactive glutamatergic system in clinical depression. Recently, the metabotropic glutamate receptor 5 (mGluR5) has been proposed as an attractive target for novel therapeutic approaches to depression. The goal of this study was to compare mGluR5 binding (in a positron emission tomography [PET] study) and mGluR5 protein expression (in a postmortem study) between individuals with major depressive disorder and psychiatrically healthy comparison subjects.
METHOD:

Images of mGluR5 receptor binding were acquired using PET with [(11)C]ABP688, which binds to an allosteric site with high specificity, in 11 unmedicated individuals with major depression and 11 matched healthy comparison subjects. The amount of mGluR5 protein was investigated using Western blot in postmortem brain samples of 15 depressed individuals and 15 matched comparison subjects.
RESULTS:

The PET study revealed lower levels of regional mGluR5 binding in the prefrontal cortex, the cingulate cortex, the insula, the thalamus, and the hippocampus in the depression group relative to the comparison group. Severity of depression was negatively correlated with mGluR5 binding in the hippocampus. The postmortem study showed lower levels of mGluR5 protein expression in the prefrontal cortex (Brodmann's area 10) in the depression group relative to the comparison group, while prefrontal mGluR1 protein expression did not differ between groups.
CONCLUSIONS:

The lower levels of mGluR5 binding observed in the depression group are consonant with the lower levels of protein expression in brain tissue in the postmortem depression group. Thus, both studies suggest that basal or compensatory changes in excitatory neurotransmission play roles in the pathophysiology of major depression.

PMID:
    21498461

Neurol Res Int. 2010;2010:671421. Epub 2010 Jun 10.
Medial orbitofrontal cortex is associated with fatigue sensation.
Tajima S, Yamamoto S, Tanaka M, Kataoka Y, Iwase M, Yoshikawa E, Okada H, Onoe H, Tsukada H, Kuratsune H, Ouchi Y, Watanabe Y.
Source

Hyogo Children's Sleep and Development Medical Research Center, Hyogo Rehabilitation Centre Central Hospital, 1070 Akebono-cho, Nishi-ku, Kobe 651-2181, Japan.
Abstract

Fatigue is an indispensable bioalarm to avoid exhaustive state caused by overwork or stresses. It is necessary to elucidate the neural mechanism of fatigue sensation for managing fatigue properly. We performed H(2) ( 15)O positron emission tomography scans to indicate neural activations while subjects were performing 35-min fatigue-inducing task trials twice. During the positron emission tomography experiment, subjects performed advanced trail-making tests, touching the target circles in sequence located on the display of a touch-panel screen. In order to identify the brain regions associated with fatigue sensation, correlation analysis was performed using statistical parametric mapping method. The brain region exhibiting a positive correlation in activity with subjective sensation of fatigue, measured immediately after each positron emission tomography scan, was located in medial orbitofrontal cortex (Brodmann's area 10/11). Hence, the medial orbitofrontal cortex is a brain region associated with mental fatigue sensation. Our findings provide a new perspective on the neural basis of fatigue.

PMID:
    21188225

J Neurosci. 2010 Jul 28;30(30):10039-47.
Multiple mechanisms of consciousness: the neural correlates of emotional awareness.
Amting JM, Greening SG, Mitchell DG.
Source

Department of Psychiatry and Department of Anatomy and Cell Biology, Schulich School of Medicine and Dentistry, The University of Western Ontario, 339 Windermere Road, London, Ontario, Canada.
Abstract

Emotional stimuli, including facial expressions, are thought to gain rapid and privileged access to processing resources in the brain. Despite this access, we are conscious of only a fraction of the myriad of emotion-related cues we face everyday. It remains unclear, therefore, what the relationship is between activity in neural regions associated with emotional representation and the phenomenological experience of emotional awareness. We used functional magnetic resonance imaging and binocular rivalry to delineate the neural correlates of awareness of conflicting emotional expressions in humans. Behaviorally, fearful faces were significantly more likely to be perceived than disgusted or neutral faces. Functionally, increased activity was observed in regions associated with facial expression processing, including the amygdala and fusiform gyrus during emotional awareness. In contrast, awareness of neutral faces and suppression of fearful faces were associated with increased activity in dorsolateral prefrontal and inferior parietal cortices. The amygdala showed increased functional connectivity with ventral visual system regions during fear awareness and increased connectivity with perigenual prefrontal cortex (pgPFC; Brodmann's area 32/10) when fear was suppressed. Despite being prioritized for awareness, emotional items were associated with reduced activity in areas considered critical for consciousness. Contributions to consciousness from bottom-up and top-down neural regions may be additive, such that increased activity in specialized regions within the extended ventral visual system may reduce demands on a frontoparietal system important for awareness. The possibility is raised that interactions between pgPFC and the amygdala, previously implicated in extinction, may also influence whether or not an emotional stimulus is accessible to consciousness.

PMID:
    20668188

Neuroimage. 2011 Jan 1;54(1):645-52. Epub 2010 Jul 27.
Neural substrates of implicit cueing effect on prospective memory.
Hashimoto T, Umeda S, Kojima S.
Source

Riken BSI Symbolic Cognitive Development, Wako, Saitama, Japan. t-hashimoto@brain.riken.jp
Abstract

Functional magnetic resonance imaging was used to examine the maintenance of intentions during an ongoing task involving implicit cues. Participants were required to detect target words while engaging in the ongoing task. Cues matched to the target category and cues matched to the action for targets were presented implicitly during the ongoing task. Implicit categorical target cues were found to enhance prospective memory performance, and implicit action cues accelerated responses more than irrelevant implicit cues in the prospective memory task. We found increased caudal anterior cingulate cortex (cACC) activity during the ongoing task with both implicit target and action cues, suggesting that alertness or preparatory attentional processes were strengthened by implicit cues. Implicit target cues elicited enhanced activity in the lateral anterior prefrontal cortex (Brodmann's area 10), which may be involved in dual processing of the ongoing task and the maintained intention. These results suggest that implicit cues may boost primitive attention toward an intended action and may be accessible to off-line maintenance. The facilitation of prospective target detection and the action execution by target cues were associated with increased supplementary motor area (SMA) activity. In contrast, we found enhanced premotor cortex (PMC) activation with action cue during the prospective memory task, suggesting that the PMC may be involved in stimulus-induced and rather automatic action. These results demonstrate the effectiveness of implicit cues for examining the maintenance of intention. Overall, we found that implicit target cues can facilitate prospective memory performance, and implicit action cues can accelerate responses. The above-mentioned neural underpinnings suggest that attentional and motor control processes are involved in the enhancement of prospective memory.

Copyright © 2010 Elsevier Inc. All rights reserved.

PMID:
    20673802

Neuroimage. 2005 Dec;28(4):787-96. Epub 2005 Jun 17.
Thinking about intentions.
den Ouden HE, Frith U, Frith C, Blakemore SJ.
Source

Institute of Cognitive Neuroscience, Department of Psychology, University College London, UK.
Abstract

In this fMRI study, we investigated the convergence of underlying neural networks in thinking about a scenario involving one's own intentional action and its consequences and setting up and holding in mind an intention to act. A factorial design was employed comprising two factors: i. Causality (intentional or physical events) and ii. Prospective Memory (present or absent). In each condition, subjects answered questions about various hypothetical scenarios, which related either to the link between the subject's own intentions and consequential actions (Intentional Causality) or to the link between a natural, physical event and its consequences (Physical Causality). A prospective memory task was embedded in half the blocks. In this task, subjects were required to keep in mind an intention (to press a key on seeing a red stimulus background) whilst carrying out the ongoing Causality task. Answering questions about intentional causality versus physical causality activated a network of regions that have traditionally been associated with Theory of Mind, including the medial prefrontal cortex (mPFC), the superior temporal sulcus and the temporal poles bilaterally. In addition, the precuneus bordering with posterior cingulate cortex, an area involved in self-awareness and self-related processing, was activated more when thinking about intentional causality. In the prospective memory task, activations were found in the right parietal cortex, frontopolar cortex (BA 10) and precuneus. Different subregions within the precuneus/posterior cingulate cortex were activated in both main effects of intentional causality and prospective memory. Therefore, the precuneus/posterior cingulate cortex subserves separately thinking about one's own intentions and consequent actions and bearing in mind an intention to make an action. Previous studies have shown that prospective memory, requiring the formation of an intention and the execution of a corresponding action, is associated with decreased activation in the dorsal mPFC, close to the region activated in Theory of Mind tasks. Here, we found that holding in mind an intention to act and at the same time thinking about an intentional action led to reduced activity in a dorsal section of the mPFC. This was a different region from a more anterior, inferior dorsal mPFC region that responded to intentional causality. This suggests that different regions of mPFC play different roles in thinking about intentions.

PMID:
    15964210

J Biol Chem. 2011 Sep 2;286(35):30561-70. Epub 2011 Jul 11.
Sirtuin 1 (SIRT1) deacetylase activity is not required for mitochondrial biogenesis or peroxisome proliferator-activated receptor-gamma coactivator-1alpha (PGC-1alpha) deacetylation following endurance exercise.
Philp A, Chen A, Lan D, Meyer GA, Murphy AN, Knapp AE, Olfert IM, McCurdy CE, Marcotte GR, Hogan MC, Baar K, Schenk S.
Source

Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California 95616, USA.
Abstract

The protein deacetylase, sirtuin 1 (SIRT1), is a proposed master regulator of exercise-induced mitochondrial biogenesis in skeletal muscle, primarily via its ability to deacetylate and activate peroxisome proliferator-activated receptor-? coactivator-1a (PGC-1a). To investigate regulation of mitochondrial biogenesis by SIRT1 in vivo, we generated mice lacking SIRT1 deacetylase activity in skeletal muscle (mKO). We hypothesized that deacetylation of PGC-1a and mitochondrial biogenesis in sedentary mice and after endurance exercise would be impaired in mKO mice. Skeletal muscle contractile characteristics were determined in extensor digitorum longus muscle ex vivo. Mitochondrial biogenesis was assessed after 20 days of voluntary wheel running by measuring electron transport chain protein content, enzyme activity, and mitochondrial DNA expression. PGC-1a expression, nuclear localization, acetylation, and interacting protein association were determined following an acute bout of treadmill exercise (AEX) using co-immunoprecipitation and immunoblotting. Contrary to our hypothesis, skeletal muscle endurance, electron transport chain activity, and voluntary wheel running-induced mitochondrial biogenesis were not impaired in mKO versus wild-type (WT) mice. Moreover, PGC-1a expression, nuclear translocation, activity, and deacetylation after AEX were similar in mKO versus WT mice. Alternatively, we made the novel observation that deacetylation of PGC-1a after AEX occurs in parallel with reduced nuclear abundance of the acetyltransferase, general control of amino-acid synthesis 5 (GCN5), as well as reduced association between GCN5 and nuclear PGC-1a. These findings demonstrate that SIRT1 deacetylase activity is not required for exercise-induced deacetylation of PGC-1a or mitochondrial biogenesis in skeletal muscle and suggest that changes in GCN5 acetyltransferase activity may be an important regulator of PGC-1a activity after exercise.

PMID:
    21757760

J Neuroinflammation. 2010 Dec 17;7:93.
Fractalkine receptor (CX3CR1) deficiency sensitizes mice to the behavioral changes induced by lipopolysaccharide.
Corona AW, Huang Y, O'Connor JC, Dantzer R, Kelley KW, Popovich PG, Godbout JP.
Source

Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University, 333 W. 10th Ave., Columbus, OH 43210, USA. Angela.Wynne@osumc.edu
Abstract
BACKGROUND:

Interactions between fractalkine (CX3CL1) and fractalkine receptor (CX3CR1) regulate microglial activation in the CNS. Recent findings indicate that age-associated impairments in CX3CL1 and CX3CR1 are directly associated with exaggerated microglial activation and an impaired recovery from sickness behavior after peripheral injection of lipopolysaccharide (LPS). Therefore, the purpose of this study was to determine the extent to which an acute LPS injection causes amplified and prolonged microglial activation and behavioral deficits in CX3CR1-deficient mice (CX3CR1-/-).
METHODS:

CX3CR1-/- mice or control heterozygote mice (CX3CR1+/-) were injected with LPS (0.5 mg/kg i.p.) or saline and behavior (i.e., sickness and depression-like behavior), microglial activation, and markers of tryptophan metabolism were determined. All data were analyzed using Statistical Analysis Systems General Linear Model procedures and were subjected to one-, two-, or three-way ANOVA to determine significant main effects and interactions.
RESULTS:

LPS injection caused a prolonged duration of social withdrawal in CX3CR1-/- mice compared to control mice. This extended social withdrawal was associated with enhanced mRNA expression of IL-1ß, indolamine 2,3-dioxygenase (IDO) and kynurenine monooxygenase (KMO) in microglia 4 h after LPS. Moreover, elevated expression of IL-1ß and CD14 was still detected in microglia of CX3CR1-/- mice 24 h after LPS. There was also increased turnover of tryptophan, serotonin, and dopamine in the brain 24 h after LPS, but these increases were independent of CX3CR1 expression. When submitted to the tail suspension test 48 and 72 h after LPS, an increased duration of immobility was evident only in CX3CR1-/- mice. This depression-like behavior in CX3CR1-/- mice was associated with a persistent activated microglial phenotype in the hippocampus and prefrontal cortex.
CONCLUSIONS:

Taken together, these data indicate that a deficiency of CX3CR1 is permissive to protracted microglial activation and prolonged behavioral alterations in response to transient activation of the innate immune system.

PMID:
    21167054

J Biol Chem. 2011 Sep 16;286(37):32713-22. Epub 2011 Jul 19.
CX3CR1 Protein Signaling Modulates Microglial Activation and Protects against Plaque-independent Cognitive Deficits in a Mouse Model of Alzheimer Disease.
Cho SH, Sun B, Zhou Y, Kauppinen TM, Halabisky B, Wes P, Ransohoff RM, Gan L.
Source

From the Gladstone Institute of Neurological Disease and.
Abstract

Aberrant microglial activation has been proposed to contribute to the cognitive decline in Alzheimer disease (AD), but the underlying molecular mechanisms remain enigmatic. Fractalkine signaling, a pathway mediating the communication between microglia and neurons, is deficient in AD brains and down-regulated by amyloid-ß. Although fractalkine receptor (CX3CR1) on microglia was found to regulate plaque load, no functional effects have been reported. Our study demonstrates that CX3CR1 deficiency worsens the AD-related neuronal and behavioral deficits. The effects were associated with cytokine production but not with plaque deposition. Ablation of CX3CR1 in mice overexpressing human amyloid precursor protein enhanced Tau pathology and exacerbated the depletion of calbindin in the dentate gyrus. The levels of calbindin in the dentate gyrus correlated negatively with those of tumor necrosis factor a and interleukin 6, suggesting neurotoxic effects of inflammatory factors. Functionally, removing CX3CR1 in human amyloid precursor protein mice worsened the memory retention in passive avoidance and novel object recognition tests, and their memory loss in the novel object recognition test is associated with high levels of interleukin 6. Our findings identify CX3CR1 as a key microglial pathway in protecting against AD-related cognitive deficits that are associated with aberrant microglial activation and elevated inflammatory cytokines.

PMID:
    21771791

Behav Neurosci. 2010 Oct;124(5):645-55.
Dopamine activity in the lateral anterior hypothalamus modulates AAS-induced aggression through D2 but not D5 receptors.
Schwartzer JJ, Melloni RH Jr.
Source

Behavioral Neuroscience Program, Department of Psychology, Northeastern University, 360 Huntington Avenue, Boston, MA 02115, USA.
Abstract

Treatment with anabolic-androgenic steroids (AAS) throughout adolescence facilitates offensive aggression in Syrian hamsters. In the anterior hypothalamus (AH), the dopaminergic neural system undergoes alterations after repeated exposure to AAS, producing elevated aggression. Previously, systemic administration of selective dopamine receptor antagonists has been shown to reduce aggression in various species and animal models. However, these reductions in aggression occur with concomitant alterations in general arousal and mobility. Therefore, to control for these systemic effects, the current studies utilized microinjection techniques to determine the effects of local antagonism of D2 and D5 receptors in the AH on adolescent AAS-induced aggression. Male Syrian hamsters were treated with AAS throughout adolescence and tested for aggression after local infusion of the D2 antagonist eticlopride, or the D5 antagonist SCH-23390, into the AH. Treatment with eticlopride showed dose-dependent suppression of aggressive behavior in the absence of changes in mobility. Conversely, while injection of SCH-23390 suppressed aggressive behavior, these reductions were met with alterations in social interest and locomotor behavior. To elucidate a plausible mechanism for the observed D5 receptor mediation of AAS-induced aggression, brains of AAS and sesame oil-treated animals were processed for double-label immunofluorescence of GAD67 (a marker for GABA production) and D5 receptors in the lateral subdivision of the AH (LAH). Results indicate a sparse distribution of GAD67 neurons colocalized with D5 receptors in the LAH. Together, these results indicate that D5 receptors in the LAH modulate non-GABAergic pathways that indirectly influence aggression control, while D2 receptors have a direct influence on AAS-induced aggression.

(PsycINFO Database Record (c) 2010 APA, all rights reserved).

PMID:
    20939664

Neuroscience. 2011 Jun 30;185:85-96. Epub 2011 Apr 1.
Glutamate-vasopressin interactions and the neurobiology of anabolic steroid-induced offensive aggression.
Carrillo M, Ricci LA, Melloni RH.
Source

Behavioral Neuroscience Program, Department of Psychology, 125 Nightingale Hall, Northeastern University, 360 Huntington Avenue, Boston, MA 02155, USA.
Abstract

In the latero-anterior hypothalamus (LAH) increased glutamate and vasopressin (AVP) activity facilitate anabolic androgenic steroid (AAS)-induced offensive aggression. In addition, adolescent AAS treatment increases the strength of glutamate-mediated connections between the LAH and the brain nucleus of stria terminalis (BNST). The current set of studies used male Syrian hamsters exposed to AAS during adolescence to examine whether increased glutamate-mediated stimulation of the BNST is dependent on LAH-AVP signaling and whether this neural pathway modulates adolescent AAS-induced offensive aggression. In the first set of AAS-treated animals offensive aggression was measured following blockade of glutamate activity within the BNST using NBQX. Then, in a second group of AAS-treated animals aggression levels were examined following simultaneous blockade of LAH-AVP activity using Manning compound and stimulation of BNST glutamate using AMPA. Lastly, the number of AVP fibers in apposition to glutamate cells was examined in AAS and control animals, using double-label immunofluorescence. The results showed that administration of NBQX into the BNST dose-dependently reduced aggressive behavior in AAS-treated animals. Further, the current results replicated previous findings showing that blockade of LAH-AVP significantly reduces aggressive behavior in AAS-treated animals. In these animals stimulation of BNST-AMPA receptors had a linear effect on aggression, where the smallest dose exacerbated the inhibitory effect of the V1a antagonist, the medium dose had no effect and the highest dose recuperated aggression to control levels. Finally when compared with control animals, AAS treatment produced a significant increase in the number of AVP fibers in apposition to LAH-glutamate cells. Overall, these results identify the BNST as a key brain region involved in aggression control and provide strong evidence suggesting that AVPergic-mediated stimulation of BNST-glutamate is a possible mechanism that facilitates aggression expression in adolescent AAS-treated animals.

Copyright © 2011. Published by Elsevier Ltd.

PMID:
    21459130

Brain Struct Funct. 2011 Sep 21. [Epub ahead of print]
Orexinergic innervation of the extended amygdala and basal ganglia in the rat.
Schmitt O, Usunoff KG, Lazarov NE, Itzev DE, Eipert P, Rolfs A, Wree A.
Source

Institute of Anatomy, University of Rostock, P. O. Box 100888, 18055, Rostock, Germany, schmitt@med.uni-rostock.de.
Abstract

The orexinergic system interacts with several functional states of emotions, stress, hunger, wakefulness and behavioral arousal through four pathways originating in the lateral hypothalamus (LH). Hundreds of orexinergic efferents have been described by tracing studies and direct immunohistochemistry of orexin in the forebrain, olfactory regions, hippocampus, amygdala, septum, basal ganglia, thalamus, hypothalamus, brain stem and spinal cord. Most of these tracing studies investigated the whole orexinergic projection to all regions of the intracranial part of the CNS. To identify the orexinergic efferents at the subnuclear level of resolution, we focussed on the orexinergic target in the amygdala, which is substantially involved in the LH output and contributes mostly to the functional outcome of the orexinergic system and the basal ganglia. Immunohistochemical identification of axonal orexin A and orexin B in male adult rats has been performed on serial sections. In the extended amygdala many new orexinergic targets were found in the anterior amygdaloid area (dense), anterior cortical nucleus (moderate), amygdalostriatal transition region (moderate), basolateral regions (moderate), basomedial nucleus (moderate), several bed nucleus of the stria terminals regions (few to dense), central amygdaloid subdivisions (dense), posteromedial cortical nucleus (moderate) and medial amygdaloid subnuclei (dense). Furthermore, the entopeduncular nucleus has been newly identified as another target for orexinergic fibers with a high density. These results suggest that subdivisions and subnuclei of the extended amygdala are specific targets of the orexinergic system.

PMID:
    21935673

Zh Evol Biokhim Fiziol. 2011 May-Jun;47(3):223-31.
[Functional role of hypothalamic D1 and D2 receptors in organization of some forms of behavior of the common frog].
[Article in Russian]
Aristakesian EA.
Abstract

Dopamine is one of the most ancient, widely spread neurotransmitters that performs a great number of neuromodulator effects in the vertebrate CNS. For the last few years there considerably increases an interest in study of functional role of this neurotransmitter in regulation of various forms of behavior of poikilothermal vertebrates. The present work deals with study of the role of the dopaminergic system, specifically of the hypothalamic dophaminergic system in providing some behavioral frog reactions. We studies behavior of the animals in the "open field" before and after administration to them of antagonists of D1 (SCH 23390) and D2 (haloperidol) receptors as well as of animals with destructed anterior and posterior parts of hypothalamis. Administration of SCH 23390 to intact frogs caused a statistically significant decrease of the number of exploratory reactions and goal-oriented jumps, whereas haloperidol only moderately increased the number of the above reactions. Destruction of the posterior part of hypothalamus inhibited essentially all kinds of activity, while destruction of the anterior part suppressed them completely. Antagonists of D1 and D2 receptors of dopamin little changed the initial motor and emotional activity of the operated animals. The obtained data are discussed in the light of evolutionary origin of D1 and D2 receptors in the vertebrate subphylum and allow concluding that D1 and D2 receptors of hypothalamic dophamin of the common frog are located predominantly in the anterior hypothalamic areas and that their effect on behavior can be mediated and is associated with other brain neurotransmitter systems in such brain structures as lateral hypothalamus, locus coereleus, and striatum that provide different aspects of wakefulness.

PMID:
    21780642

Curr Opin Clin Nutr Metab Care. 2011 Jan;14(1):41-8.
The role of the antioxidant and longevity-promoting Nrf2 pathway in metabolic regulation.
Sykiotis GP, Habeos IG, Samuelson AV, Bohmann D.
Source

Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, USA.
Abstract
PURPOSE OF REVIEW:

The vertebrate cap'n'collar family transcription factor Nrf2 and its invertebrate homologues SKN-1 (in worms) and CncC (in flies) function as master mediators of antioxidant and detoxification responses and regulators of the cellular redox state. Nrf2 controls gene expression programs that defend various tissues against diverse electrophilic stressors and oxidative insults, thus protecting the organism from disorders that are caused or exacerbated by such stresses. Moreover, studies on model organisms implicate the Nrf2 pathway in the prevention of aging-related diseases and suggest that SKN-1-regulated and CncC-regulated gene expression can promote longevity. These facets of Nrf2 signaling have been thoroughly reviewed. This article discusses another aspect of the Nrf2 pathway's function that has not yet received the same degree of attention, but emerges as a topic of increasing interest and potential clinical impact: its role in metabolic regulation and its interaction with central signaling systems that respond to nutritional inputs.
RECENT FINDINGS:

Recent evidence identifies Nrf2 signaling as a mediator of the salutary effects of caloric restriction. Nrf2 signaling also crosstalks with metabolic signaling systems such as the insulin/Akt pathway as well as with the metabolism of lipids. Moreover, Nrf2 has a protective role in models of diabetic nephropathy.
SUMMARY:

The emerging role of Nrf2 as an effector of metabolic and longevity signals offers new therapeutic perspectives. The potential impact of pharmacological manipulation of Nrf2 signaling as a strategy for the prevention and treatment of metabolic disease can be envisioned.

PMID:
    21102319

Chem Biol Interact. 2011 Jun 30;192(1-2):37-45. Epub 2010 Oct 23.
The cap'n'collar transcription factor Nrf2 mediates both intrinsic resistance to environmental stressors and an adaptive response elicited by chemopreventive agents that determines susceptibility to electrophilic xenobiotics.
Higgins LG, Hayes JD.
Source

Biomedical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee DD1 9SY, Scotland, United Kingdom.
Abstract

Transcription factor Nrf2 regulates genes encoding drug-metabolising enzymes and drug transporters, as well as enzymes involved in the glutathione, thioredoxin and peroxiredoxin antioxidant pathways. Using mouse embryonic fibroblast (MEF) cells from Nrf2(+/+) and Nrf2(-/-) mice, in conjunction with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay, we have shown that loss of Nrf2 diminishes the intrinsic resistance of mutant fibroblasts towards isothiocyanates (i.e. sulforaphane), epoxides (i.e. (2S,3S)-(-)-3-phenylglycidol, ethyl 3-phenylglycidate and styrene-7,8-epoxide), peroxides, hydroquinones and quinones (i.e. tert-butylhydroperoxide, tert-butylhydroquinone and 2,3-dimethoxynaphthoquinone), NaAsO(2), and various mutagens, including ß-propiolactone, cisplatin, mechlorethamine and methyl methanesulfonate to ~50% of that observed in equivalent wild-type cells. Exposure of Nrf2(+/+) fibroblasts, but not Nrf2(-/-) fibroblasts, to a non-toxic dose (3µmol/l) of the chemopreventive agent sulforaphane (Sul) stimulated an adaptive response that, 18h after first being subjected to the isothiocyanate, caused an induction of between 2- and 10-fold in the levels of mRNA for glutamate-cysteine ligase catalytic (Gclc) and modifier (Gclm) subunits, glutathione S-transferases and NAD(P)H:quinone oxidoreductase-1 (Nqo1); this was accompanied by an increase in total glutathione of between 1.5- and 1.9-fold. Pre-treatment of Nrf2(+/+) MEF cells with 3µM Sul for 18h prior to challenge with xenobiotics, conferred between 2.0- and 4.0-fold protection against isothiocyanates, reactive carbonyls, peroxides, quinones, NaAsO(2), and the anticancer nitrogen mustard chlorambucil, but pre-treatment with 3µM Sul produced no such increased tolerance in Nrf2(-/-) MEF cells. The inducible resistance towards acrolein, cumene hydroperoxide and chlorambucil, produced by pre-treating wild-type fibroblasts with 3µM Sul, was dependent on glutathione because simultaneous pre-treatment with 5µmol/l buthionine sulfoximine abolished the increased tolerance of these xenobiotics. However, inducible resistance towards menadione that occurred upon pre-treatment with 3µM Sul was independent of glutathione and may be due to upregulation of Nqo1. Thus Nrf2 controls cellular resistance against electrophiles.

Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

PMID:
    20932822

Planta Med. 2008 Oct;74(13):1526-39. Epub 2008 Oct 20.
Nrf2 as a master redox switch in turning on the cellular signaling involved in the induction of cytoprotective genes by some chemopreventive phytochemicals.
Surh YJ, Kundu JK, Na HK.
Source

National Research Laboratory of Molecular Carcinogenesis and Chemoprevention, College of Pharmacy, Seoul National University, Seoul, South Korea. surh@plaza.snu.ac.kr
Abstract

A wide array of dietary phytochemicals have been reported to induce the expression of enzymes involved in both cellular antioxidant defenses and elimination/inactivation of electrophilic carcinogens. Induction of such cytoprotective enzymes by edible phytochemicals largely accounts for their cancer chemopreventive and chemoprotective activities. Nuclear factor-erythroid-2-related factor 2 (Nrf2) plays a crucial role in the coordinated induction of those genes encoding many stress-responsive and cytoptotective enzymes and related proteins. These include NAD(P)H:quinone oxidoreductase-1, heme oxygenase-1, glutamate cysteine ligase, glutathione S-transferase, glutathione peroxidase, thioredoxin, etc. In resting cells, Nrf2 is sequestered in the cytoplasm as an inactive complex with the repressor Kelch-like ECH-associated protein 1 (Keap1). The release of Nrf2 from its repressor is most likely to be achieved by alterations in the structure of Keap1. Keap1 contains several reactive cysteine residues that function as sensors of cellular redox changes. Oxidation or covalent modification of some of these critical cysteine thiols would stabilize Nrf2, thereby facilitating nuclear accumulation of Nrf2. After translocation into nucleus, Nrf2 forms a heterodimer with other transcription factors, such as small Maf, which in turn binds to the 5'-upstream CIS-acting regulatory sequence, termed antioxidant response elements (ARE) or electrophile response elements (EpRE), located in the promoter region of genes encoding various antioxidant and phase 2 detoxifying enzymes. Certain dietary chemopreventive agents target Keap1 by oxidizing or chemically modifying one or more of its specific cysteine thiols, thereby stabilizing Nrf2. In addition, phosphorylation of specific serine or threonine residues present in Nrf2 by upstream kinases may also facilitate the nuclear localization of Nrf2. Multiple mechanisms of Nrf2 activation by signals mediated by one or more of the upstream kinases, such as mitogen-activated protein kinases, phosphatidylionositol-3-kinase/Akt, protein kinase C, and casein kinase-2 have recently been proposed. This review highlights the cytoprotective gene expression induced by some representative dietary chemopreventive phytochemicals with the Nrf2-Keap1 system as a prime molecular target.

PMID:
    18937164

Carcinogenesis. 2009 Oct;30(10):1754-62. Epub 2009 Jul 24.
1-Cyano-2,3-epithiopropane is a novel plant-derived chemopreventive agent which induces cytoprotective genes that afford resistance against the genotoxic alpha,beta-unsaturated aldehyde acrolein.
Kelleher MO, McMahon M, Eggleston IM, Dixon MJ, Taguchi K, Yamamoto M, Hayes JD.
Source

Biomedical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Scotland, UK.
Abstract

Epithionitriles represent a previously unrecognized class of cancer chemopreventive phytochemical generated from alkenyl glucosinolates in cruciferous vegetables. In rat liver RL-34 epithelial cells, 1-cyano-2,3-epithiopropane (CETP), 1-cyano-3,4-epithiobutane (CETB) and 1-cyano-4,5-epithiopentane (CETPent) were shown to induce cytoprotective enzymes including NAD(P)H:quinone oxidoreductase 1 (NQO1), glutathione (GSH) S-transferase A3 and the glutamate-cysteine ligase modifier subunit; CETP was more potent in this regard than were either CETB or CETPent, with 50 microM CETP eliciting a remarkable approximately 10-fold induction of NQO1. Furthermore, 50 microM CETP stimulated a 2.0-fold overproduction of GSH in RL-34 cells. Transfection experiments demonstrated that epithionitriles induced gene expression through an antioxidant response element (ARE) and that transactivation of an Nqo1-luciferase reporter plasmid was dependent on NF-E2 p45-related factor 2 (Nrf2), a cap'n'collar basic region leucine zipper transcription factor. Evidence is presented that CETP affected Nrf2-mediated induction of ARE-driven transcription by inhibiting Kelch-like ECH-associated protein 1 (Keap1), a ubiquitin ligase substrate adaptor that negatively regulates Nrf2. We found that Nqo1 was expressed constitutively at high levels in Keap1(-/-) mouse embryonic fibroblasts (MEFs) and it was not further induced by CETP. However, knock-in of mouse Keap1 or zebrafish Keap1a into Keap1(-/-) MEFs repressed Nqo1-luciferase reporter gene activity, but repression by the murine or zebrafish proteins was antagonized by CETP. Pre-treatment of Nrf2(+/+) MEFs, but not Nrf2(-/-) MEFs, with 15 microM CETP for 24 h conferred 2.4-fold resistance against subsequent exposure to the alpha,beta-unsaturated aldehyde acrolein, indicating that the phytochemical exerts chemopreventive properties against genotoxic xenobiotics.

PMID:
    19633057

Expert Rev Mol Med. 2009 Jun 3;11:e17.
The Nrf2-ARE cytoprotective pathway in astrocytes.
Vargas MR, Johnson JA.
Source

Division of Pharmaceutical Sciences, University of Wisconsin, Madison, WI 53705, USA.
Abstract

The expression of phase-II detoxification and antioxidant enzymes is governed by a cis-acting regulatory element named the antioxidant response element (ARE). ARE-containing genes are regulated by the nuclear factor erythroid-2-related factor 2 (Nrf2), a member of the Cap'n'Collar basic-leucine-zipper family of transcription factors. ARE-regulated genes are preferentially activated in astrocytes, which consequently have more efficient detoxification and antioxidant defences than neurons. Astrocytes closely interact with neurons to provide structural, metabolic and trophic support, as well as actively participating in the modulation of neuronal excitability and neurotransmission. Therefore, functional alterations in astrocytes can shape the interaction with surrounding cells, such as neurons and microglia. Activation of Nrf2 in astrocytes protects neurons from a wide array of insults in different in vitro and in vivo paradigms, confirming the role of astrocytes in determining the vulnerability of neurons to noxious stimuli. Here, we review the current data supporting Nrf2 activation in astrocytes as a viable therapeutic approach, not only in acute neuronal damage, but also in chronic neurodegeneration related to oxidative stress.

PMID:
    19490732

Acta Pharmacol Sin. 2007 Apr;28(4):459-72.
Natural dietary anti-cancer chemopreventive compounds: redox-mediated differential signaling mechanisms in cytoprotection of normal cells versus cytotoxicity in tumor cells.
Nair S, Li W, Kong AN.
Source

Graduate Program in Pharmaceutical Sciences and Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers-The State University of New Jersey, Piscataway, NJ 08854, USA.
Abstract

Many dietary phytochemicals exhibit health-beneficial effects including prevention of diseases such as cancer, as well as neurological, cardiovascular, inflammatory, and metabolic diseases. Evolutionarily, herbivorous and omnivorous animals have been ingesting plants. This interaction between "animal-plant" ecosystems has resulted in an elaborate system of detoxification and defense mechanisms evolved by animals including humans. Mammalian cells, including human cells, respond to these dietary phytochemicals by "non-classical receptor sensing" mechanisms of electrophilic chemical-stress typified by "thiol-modulated" cellular signaling events primarily leading to the gene expression of pharmacologically beneficial effects, but sometimes unwanted cytotoxicity also. Our laboratory has been studying two groups of dietary phytochemical cancer-chemopreventive compounds (isothiocyanates and polyphenols), which are effective in chemical-induced, as well as genetically-induced, animal carcinogenesis models. These compounds typically generate "cellular stress" and modulate gene expression of phase II detoxifying/antioxidant enzymes. Electrophiles, reactive oxygen species, and reactive nitrogen species are known to act as second messengers in the modulation of many cellular signaling pathways leading to gene expression changes and pharmacological responses. Redox-sensitive transcription factors such as nuclear factor-E2-related factor 2 (Nrf2), AP-1, NF-kappaB, to cite a few examples, sense and transduce changes in the cellular redox status and modulate gene expression responses to oxidative and electrophilic stresses, presumably via sulfhydryl modification of critical cysteine residues found on these proteins and/or other upstream redox-sensitive molecular targets. In the current review, we will explore dietary cancer chemopreventive phytochemicals, discuss the link between oxidative/electrophilic stresses and the redox circuitry, and consider different redox-sensitive transcription factors. We will also discuss the kelch-like erythroid Cap'n'Collar homologue-associated protein 1 (Keap1)-Nrf2 axis in redox signaling of induction of phase II detoxifying/antioxidant defense mechanisms, an important target and preventive strategy for normal cells against carcinogenesis, and the converse inhibition of cell growth/inflammatory signaling pathways that would confer therapeutic intervention in many types of cancers. Finally, we will summarize the Nrf2 paradigm in gene expression, the pharmacotoxicogenomic relevance of redox-sensitive Nrf2, and the redox regulation of cell death mechanisms.

PMID:
    17376285

Chin Med. 2010 Oct 27;5:37.
Anti-cancer and potential chemopreventive actions of ginseng by activating Nrf2 (NFE2L2) anti-oxidative stress/anti-inflammatory pathways.
Saw CL, Wu Q, Kong AN.
Source

Center for Cancer Prevention Research, Ernest Mario School of Pharmacy, Rutgers, the State University of New Jersey, USA. constancesaw@gmail.com.
Abstract

This article reviews recent basic and clinical studies of ginseng, particularly the anti-cancer effects and the potential chemopreventive actions by activating the transcriptional factor, nuclear factor (erythroid-derived 2)-like 2 (Nrf2 or NFE2L2)-mediated anti-oxidative stress or anti-inflammatory pathways. Nrf2 is a novel target for cancer prevention as it regulates the antioxidant responsive element (ARE), a critical regulatory element in the promoter region of genes encoding cellular phase II detoxifying and anti-oxidative stress enzymes. The studies on the chemopreventive effects of ginseng or its components/products showed that Nrf2 could also be a target for ginseng's actions. A number of papers also demonstrated the anti-inflammatory effects of ginseng. Targeting Nrf2 pathway is a novel approach to the investigation of ginseng's cancer chemopreventive actions, including some oxidative stress and inflammatory conditions responsible for the initiation, promotion and progression of carcinogenesis.

PMID:
    20979613

AAPS J. 2011 Mar;13(1):1-13. Epub 2010 Oct 22.
Anti-inflammatory/Anti-oxidative stress activities and differential regulation of Nrf2-mediated genes by non-polar fractions of tea Chrysanthemum zawadskii and licorice Glycyrrhiza uralensis.
Wu TY, Khor TO, Saw CL, Loh SC, Chen AI, Lim SS, Park JH, Cai L, Kong AN.
Source

Graduate Program in Pharmaceutical Science, Department of Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA.
Abstract

Accumulating evidence from epidemiological studies indicates that chronic inflammation and oxidative stress play critical roles in neoplastic development. The aim of this study was to investigate the anti-inflammatory, anti-oxidative stress activities, and differential regulation of Nrf2-mediated genes by tea Chrysanthemum zawadskii (CZ) and licorice Glycyrrhiza uralensis (LE) extracts. The anti-inflammatory and anti-oxidative stress activities of hexane/ethanol extracts of CZ and LE were investigated using in vitro and in vivo approaches, including quantitative real-time PCR (qPCR) and microarray. Additionally, the role of the transcriptional factor Nrf2 (nuclear erythroid-related factor 2) signaling pathways was examined. Our results show that CZ and LE extracts exhibited potent anti-inflammatory activities by suppressing the mRNA and protein expression levels of pro-inflammatory biomarkers IL-1ß, IL-6, COX-2 and iNOS in LPS-stimulated murine RAW 264.7 macrophage cells. CZ and LE also significantly suppressed the NO production of LPS-stimulated RAW 264.7 cells. Additionally, CZ and LE suppressed the NF-?B luciferase activity in human HT-29 colon cancer cells. Both extracts also showed strong Nrf2-mediated antioxidant/Phase II detoxifying enzymes induction. CZ and LE induced NQO1, Nrf2, and UGT and antioxidant response element (ARE)-luciferase activity in human hepatoma HepG2 C8 cells. Using Nrf2 knockout [Nrf2 (-/-)] and Nrf2 wild-type (+/+) mice, LE and CZ showed Nrf2-dependent transactivation of Nrf2-mediated antioxidant and phase II detoxifying genes. In summary, CZ and LE possess strong inhibitory effects against NF-?B-mediated inflammatory as well as strong activation of the Nrf2-ARE-anti-oxidative stress signaling pathways, which would contribute to their overall health promoting pharmacological effects against diseases including cancer.

PMID:
    20967519

AAPS J. 2011 Sep;13(3):417-26. Epub 2011 Jun 3.
Examination of the pharmacokinetics of active ingredients of ginger in humans.
Yu Y, Zick S, Li X, Zou P, Wright B, Sun D.
Source

Department of Pharmaceutical Sciences, College of Pharmacy, The University of Michigan, Ann Arbor, 48109-1065, USA.

2011-10-05T14:41:00.001-07:00

Some agonists appear to be curative agents operating systems AhR was regulating in the absence of exogenous dioxin-like compounds, synergizing with endogenous AhR regulation. Notice how THC interacts with the arylhydrocarbon hydroxylase. Those studies were never duplicated to test for endogenous cannabinoid similarities. Agonists would normally reduce cancer incidences. Antagonists will help after exposure to dioxins. Agonists that we know are in safe foods probably synergize with exogenous dioxins to cause cancer, whereas the antagonists were probably more harmful at one time. If endogenous cannabinoid activity mediates AhR activity, SNPs in genes in the endometabolome may be responsible for individual sensitivity to dioxin-like compounds and play a role in complicating procedure to restore health, converging at tryptophan 2,3-dioxygenase and B and T lymphocytes.

Inhibitors: Cacao polyphenol, Molokhia, known as Egyptian spinach, Curcuma longa and curcumin, quercetin analogue flavonol-C-glucoside, kaempferol, ginkgo biloba, chrysophanol, danthron, rhein, aloe-emodin, apigenin, quercetin, anthraquinones such as emodin, Kampo formula Bakumondo-to: ophiopogonis tuber, pinelliae tuber, oryzae semen, zizyphi fructus, ginseng radix, glycyrhizzae radix. lutein and chlorophyll a and b from green tea leaves, EGCG, four theaflavins in black tea extract: theaflavin, theaflavin-3-gallate, theaflavin-3'-gallate, and theaflavin-3,3'-digallate, Siraitia grosvenorii (luo han guo) extract, proteasome inhibitors N-acetyl-leucyl-leucyl-norleucinal and lactacystin, flavone, flavonol, flavanone, catechol, melanin extracted from Thea sinensis reduced tea melanin and non-reduced, geranylgeranylacetone, vitamin A and vitamin E succinate, sage, spinach, citrus, piperine, coumestrol, brevifolincarboxylic acid, resveratrol, carnosol, capsaicin, ethanolic extracts of propolis and Baccharis dracunculifolia flavonoid aglycones, Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid)

Activators: ginseng, Fo-Ti, white oak bark, licorice, ginkgo biloba, black cohosh, corn, jalapeño pepper, green bell pepper, apple, Brussels sprout, potato, 1,4-Dihydroxyanthraquinone (quinizarin), 1,5-dihydroxyanthraquinone (anthrarufin), 1,8-dihydroxyanthraquinone (danthron), and 5-hydroxy-1,4-naphthoquinone (juglone) daidzein, resveratrol (a stilbene) structure, some flavanones such as naringenin, and flavones such as baicalein, Prunella vulgaris, cigarette smoke extract, Cordyceps militaris, diesel exhaust particle, Aminoflavone, maltol

Cacao polyphenol extract suppresses transformation of an aryl hydrocarbon receptor in C57BL/6 mice. Inhibiting the formation of a heterodimer between AhR and an aryl hydrocarbon receptor nuclear translocator in the liver. suppressed MC-induced cytochrome P4501A1 expression and NAD(P)H:quinone-oxidoreductase activity, whereas it increased glutathione S-transferase activity. PMID: 18928297
The aryl hydrocarbon receptor (AhR) has dual roles in regulating intracellular protein levels both as a ligand-activated transcription factor and as a ligand-dependent E3 ubiquitin ligase. AhR E3 ubiquitin ligase has a role in suppression of intestinal carcinogenesis by a previously undescribed ligand-dependent beta-catenin degradation pathway. Activated by both xenobiotics and natural AhR ligands, such as indole derivatives that are converted from dietary tryptophan and glucosinolates by intestinal microbes, and suppresses intestinal tumor development PMID: 19651607
Molokhia, known as Egyptian spinach, showed the strongest suppressive effect on AhR transformation among 41 kinds of extracts from vegetables and fruits. inhibiting translocation of the AhR from cytosol into the nucleus in the liver. PMID: 16115717
Curcuma longa, did not inhibit the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced translocation of the AhR into the nucleus, but rather accelerated it. . In the nucleus, curcumin inhibited the TCDD-induced heterodimerization of the AhR with an AhR nuclear translocator (Arnt), an essential partner for the transformation, and also dose-dependently inhibited the TCDD-evoked phosphorylation of both the AhR and Arnt. curcumin significantly inhibited the TCDD-induced activation of protein kinase C (PKC), which is involved in the transformation, decreased the TCDD-induced DNA-binding activity of the AhR/Arnt heterodimer, and downregulated CYP1A1 expression. binds to the AhR as a ligand, but suppresses its transformation by inhibiting the phosphorylation of AhR and Arnt, probably by PKC. PMID: 17880909
A novel quercetin analogue from stem bark of Ulmus wallichiana promoted peak bone mass achievement. 6-C-β-D-glucopyranosyl-(2S,3S)-(+)-3',4',5,7-tetrahydroxyflavanol (GTDF), a novel flavonol-C-glucoside isolated from the extracts, had a nonestrogenic bone-sparing effect. GTDF stimulated osteoblast proliferation, survival, and differentiation. GTDF transactivated the aryl hydrocarbon receptor (AhR). Activation of AhR mediated the stimulatory effect of GTDF on osteoblast proliferation and differentiation. GTDF stimulated cAMP production, which mediated osteogenic gene expression. increased the mRNA levels of AhR target genes in calvaria or bone marrow stromal cells. PMID: 21638315
(ginseng, Fo-Ti, white oak bark, licorice, ginkgo biloba, and black cohosh) stimulated AhR DNA binding and gene expression to levels between 20 and 60% of that produced by TCDD. (corn, jalapeño pepper, green bell pepper, apple, Brussels sprout, and potato) were relatively potent activators of AhR DNA binding (30-50% of TCDD), only corn and jalapeño pepper extracts induced AhR-dependent luciferase reporter gene expression. dilution of corn, jalapeño pepper, bell pepper, and potato extracts dramatically increased their ability to induce luciferase activity, suggesting that these extracts contained AhR antagonists whose effectiveness was overcome by dilution. PMID: 12926901
kaempferol or ginkgo biloba extract (EGb) containing 24% flavonol at 100 mg/kg body weight suppressed AhR transformation induced by 3-methylcholanthrene at 10 mg/kg body weight in the liver. suppressive effect of kaempferol was enhanced by verapamil, an inhibitor of P-glycoprotein (P-gp). Enhancement of the suppressive effect by verapamil was also observed in mouse hepatoma Hepa-1c1c7 cells, accompanied by an increase in the uptake of kaempferol into the cells. inhibition of P-gp enhanced the suppressive effect of kaempferol on AhR transformation through an increase in the intracellular kaempferol concentration. PMID: 19584540
a known disruptor of B-cell differentiation, binding of the AhR to dioxin responsive elements (DRE) in sensitive genes. Ig heavy chain (IgH) gene is transcriptionally inhibited by TCDD through inhibition of the 3'IgH transcriptional regulatory region (3'IgHRR). AhR as an important regulator of IgH expression. inhibition of both 3'IgHRR activation and IgH protein expression by the non-dioxin AhR activators indolo(3,2-b)carbazole, primaquine, carbaryl, and omeprazole which followed a rank order potency for AhR activation supporting a role of the AhR in the transcriptional regulation of the 3'IgHRR and IgH expression. However, modulation of the 3'IgHRR and IgH expression was not limited to AhR activators or to suppressive effects. Hydrogen peroxide and terbutaline had an activating effect and benzyl isothiocyanate was inhibitory. These chemicals are not known to influence the AhR signaling pathway but have been previously shown to modulate humoral immunity and/or transcription factors that regulate the 3'IgHRR. PMID: 19447539
TCDD-induced inhibition of micro heavy chain expression and thus of IgM secretion. 3'alpha Ig heavy chain enhancer, which is composed of four regulatory domains that span approximately 40 kb. One of these domains, hs4, contains a DRE-like site that overlaps a kappaB motif. previously demonstrated TCDD-inducible binding of both the AhR nuclear complex and NF-kappaB/Rel proteins to the DRE and kappaB motifs, respectively, as well as TCDD and LPS-induced transcriptional activity through the hs4 domain. determine if the AhR nuclear complex and NF-kappaB/Rel proteins converge at these two overlapping cis-elements and act cooperatively to influence enhancer activity. TCDD activated the hs4 fragment; however, co-treatment with LPS led to a marked and synergistic activation. AhR nuclear complex and NF-kappaB/Rel proteins converge at the DRE and kappaB motif to influence transcriptional activity of the hs4 enhancer fragment. PMID: 15212819
1,4-Dihydroxyanthraquinone (quinizarin), 1,5-dihydroxyanthraquinone (anthrarufin), 1,8-dihydroxyanthraquinone (danthron), and 5-hydroxy-1,4-naphthoquinone (juglone) strongly suppressed DNA-binding activity of the AhR induced by 0.1 nM 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), with their IC(50) values around 1 muM. hydroxyl groups at C1 or C4 but not C3 position of anthraquinone structure are critical for the suppressive effects. In human hepatoma HepG2 cells, chrysophanol, danthron, and rhein also suppressed the DNA-binding activity in a dose-dependent manner, although aloe-emodin showed a moderate effect. PMID: 19269596
marked AhR activation was exhibited by isoflavones such as daidzein, resveratrol (a stilbene) structure, some flavanones such as naringenin, and flavones such as baicalein. flavones such as apigenin, flavonols such as quercetin, and anthraquinones such as emodin, showed notable inhibitory effects. leafy green vegetables, citrus fruits, and herbs that contain food polyphenolics showed AhR-based interactions at high concentrations. PMID: 17869316
Prunella vulgaris (PV), a commonly used Chinese herb, also known as Self-heal displayed significant antiestrogenic activity. significantly reduced alkaline phosphatase activity and cell proliferation in response to estrogen in a dose-dependent manner. CYR61, an estrogen-induced protein, was blocked. not appear to directly inhibit estrogen signaling. Rather, we found that its activities were probably related to an ability to function as an aryl hydrocarbon receptor (AHR) agonist. PV induced CYP1A1, CYP1B1, and AHR repressor expression in a dose-dependent manner--responses that were blocked by small interfering RNA treatment to reduce AHR and specific AHR antagonists. immunohistochemistry demonstrated persistent estrogen receptor (ER), but reduced proliferation and CYR61 expression by PV tea treatment. ability of PV-activated AHR to interfere with estrogen. PMID: 18923163
four Kampo formulae (Bakumondo-to, Keigai-rengyo-to, Gosha-jinki-gan and Hochu-ekki-to) were administered to four representative dioxin and related organochlorine symptoms (respiratory, skin, neurological symptoms and general fatigue) for half a year. Bakumondo-to significantly improved respiratory symptoms. PMID: 19996156
lutein and chlorophyll a and b from green tea leaves as novel antagonists for AhR. suppressed AhR transformation dose-dependently with the 50% inhibitory concentration (IC(50)) values against 0.1 nM TCDD-induced AhR transformation at 3.2, 5.0, and 5.9 microM .EGCG, which is the most abundant flavonoid in green tea leaves, also showed stronger suppressive effects than did other major tea components, with the IC(50) value of 1.7 microM. through the suppression of AhR transformation. PMID: 15113147
black tea extract strongly suppressed AhR transformation compared to green and oolong tea, although the catechin contents did not change significantly among the extracts. four theaflavins as active compounds from black tea leaves. The IC(50) values of theaflavin, theaflavin-3-gallate, theaflavin-3'-gallate, and theaflavin-3,3'-digallate (Tfdg) were 4.5, 2.3, 2.2, and 0.7 muM, respectively. observed not only by pre-treatment but also by post-treatment. theaflavins inhibit the binding of TCDD to the AhR and also the binding of the transformed AhR to the specific DNA-binding site. PMID: 15914905
Siraitia grosvenorii extract inhibited the induction of gamma-glutamyltranspeptidase-positive hepatocytes, lipid peroxidation, and gene expression of Cyp1a1, all of which were caused by Dicyclanil. Cyp1a1 gene expression was significantly lower in mice administered DC + SGE. inhibited hepatocarcinogenesis, probably due to suppression of Ahr activity. PMID: 19182440
cigarette smoke extract markedly induced activation of AhR, inhibiting differentiation of preadipocytes into adipocytes with a decrease in lipid accumulation, blunted expression of adipocyte markers (adiponectin, PPAR-gamma, and C/EBPalpha), and sustained expression of a preadipocyte marker MCP-1. CSE induced ER stress in preadipocytes. Interestingly, AhR agonists did not cause ER stress, and ER stress inducers did not activate AhR. cigarette smoke has the potential to inhibit adipocyte differentiation via dual, independent mechanisms, i.e., through activation of the AhR pathway and induction of the unfolded protein response. PMID: 19141685
inducible expression of the reporter in T47D breast tumor cells with AhR ligands was significantly reduced by co-treatment with N-acetyl-leucyl-leucyl-norleucinal. the induced expression of CYP1A1 and CYP1B1 mRNAs was unaffected by ALLN. lactacystin, another proteasome inhibitor, exhibited the same effect as ALLN on reporter activity induced by AhR ligands. proteasome inhibition results in a reduction in the expression of AhR-regulated proteins. PMID: 21791387
antiadipogenic mycelia Cordyceps militaris suppressed differentiation of 3T3-L1 preadipocytes into mature adipocytes without affecting cell viability. associated with 1) a decrease in lipid accumulation, 2) blunted induction of adipocyte markers including adiponectin, peroxisome proliferator-activated receptor-gamma, and CCAAT/enhancer binding protein-alpha, and 3) sustained expression of a preadipocyte marker, monocyte chemoattractant protein-1. decreased accumulation of lipid and hypertrophy in mature adipocytes and preserved their response to insulin (phosphorylation of Akt). C. militaris has the potential to activate the aryl hydrocarbon receptor (AhR). C. militaris has the potential to interfere with adipocyte differentiation through activation of AhR. PMID: 18664595
Flavone, flavonol, and flavanone but not catechin inhibited the specific binding between the AhR and 3-methylcholanthrene dose-dependently, indicating that the former three subclasses possibly act as competitive antagonists of the AhR. However, catechin in addition to the former three subclasses directly interacted with the AhRc by surface plasmon resonance analysis. dissociation constant values showed an inverse correlation with the suppressive effect on the DNA binding activity. flavone, flavonol, and flavanone act as competitive antagonists of the AhR, while catechin associates with the AhRc and indirectly exhibits its antagonistic effects. PMID: 17560542
Reduced tea melanin (RTM) and non-reduced tea melanin (NRTM). RTM protected the animals against TCDD-induced lipid peroxidation, inhibition of glutathione peroxidase, alteration in reduced and oxidized glutathione concentrations, loss of body weight, and increased relative liver weight. NRTM was less effective as compared to RTM because of its inferior antioxidant activity, but it still displayed a strong protective effect against TCDD toxicity owing to its similar suppression of the activity of the aryl hydrocarbon receptor. Both NRTM and RTM suppressed the expression of CYP1A1 gene and prevented the activation of cytochrome P450 isozyme in the livers. dual protection against the development of TCDD-induced oxidative stress. PMID:17077530
melanin extracted from Thea sinensis Linn. antagonistic activity against different venoms. MEBT demonstrated neutralization effect against all venoms tested at dose of 3 mg. PMID: 14967198
Mitochondrial reactive oxygen production is dependent on the aromatic hydrocarbon receptor. dioxin caused a rise in succinate-stimulated mitochondrial H(2)O(2) production. Dioxin decreased mitochondrial aconitase (an enzyme inactivated by superoxide) by 44%. Dioxin treatment increased mitochondrial glutathione levels. These results suggest that both constitutive and dioxin-induced mitochondrial reactive oxygen production is associated with a function of the AHR, and these effects are independent of either CYP1A1 or CYP1A2. PMID: 12398935
Geranylgeranylacetone (GGA), an antiulcer drug, counteracts suppression of body weight gain and lethality produced by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). curcumin, a food ingredient anticipates the TCDD's toxicity on body weight gain. Both GGA and curcumin had no effect on the induction of hepatic ethoxyresorufin O-deethylase activity by TCDD. These data suggest that both compounds exhibit a protective effect against some forms of dioxin toxicity by a mechanism without involving inhibition of aryl hydrocarbon receptor activation. PMID: 15997774
Low-dose dioxins alter gene expression related to cholesterol biosynthesis, lipogenesis, and glucose metabolism. Changes in the expression of genes involved in the circadian rhythm, cholesterol biosynthesis, fatty acid synthesis, and glucose metabolism in the liver even at 5 ng/kg for 18 days. affect energy metabolism via alterations of gene expression. PMID: 18295293
vitamin A and TCDD or vitamin E succinate exhibited reduction in indicators of acute toxicity including the decrease in total body and thymus weight. also a significant reduction in the increase in liver weight as compared to TCDD only. Following one day of treatment with 50 microg TCDD/kg, vitamin A and vitamin E succinate produced a significant decrease in the production of superoxide anion by peritoneal lavage cells (P<0.05) and in DNA-single strand breaks. A significant decrease in DNA-single strand breaks in peritoneal lavage cells was observed following 5 days treatment with 50 microg TCDD/kg. PMID: 15447737
In concert with reduced body weight, TCDD increased brain TRP concentration, 5-HT synthesis and its metabolism to 5-HIAA at lethal doses in TCDD-susceptible L-E rats, and almost not at all in resistant H/W rats. TCDD indirectly increases free TRP concentration in the circulation in TCDD-susceptible L-E rats. Blood free fatty acids seem to be involved. not likely that the enhanced serotonergic tone in the CNS is a causative factor in TCDD-induced anorexia. However, the present results may open up an interesting avenue to better understand physiology of TRP and the complex regulation of energy balance. PMID: 10721086
dose-related increase in brain 5-HT turnover and plasma free tryptophan. Nonesterified fatty acids (NEFA) in the plasma were dose dependently elevated in male and female L-E rats and there was a moderate or good correlation (r = 0.654 for male and r = 0.731 for female rats) between this parameter and plasma free tryptophan. Bilirubin was dose dependently increased in the plasma of female L-E rats and there was a good correlation between plasma free tryptophan and total (r = 0.779) or conjugated (r = 0.825) bilirubin. The concentration of albumin tended to be suppressed in female L-E rats. The main tryptophan metabolizing enzyme, hepatic tryptophan pyrrolase, was inhibited in female L-E rats but not in male L-E rats. PMID: 7940543
extracts of sage, among the vegetables, green leafy ones such as spinach, and among the fruit, citrus showed inhibitory effects on AhR activation by TCDD, although some tested samples did not show parallel behavior in both assays. Sage had a remarkable inhibitory effect (79% in the CALUX assay and 83% in the Ah-Immunoassay compared with control) and its effects were dose dependent. PMID: 11853182
Ninety vegetable constituents including flavonoids, tannins, saponins, terpenes, etc., were assayed in vitro. Among them, flavones, flavonols, anthraquinones, piperine, coumestrol, brevifolincarboxylic acid, and resveratrol showed marked inhibitory effects on AhR-based bioassay activation by TCDD, and their effects were dose dependent. Curcumin, carnosol, and capsaicin also inhibited the activation of AhR in this assay, although to a lesser degree. PMID: 14646185
ethanolic extracts of propolis containing higher concentrations of flavonoids suppressed 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced aryl hydrocarbon receptor transformation in a dose-dependent manner. The IC(50) values of propolis group 3 and group 12 were 1.2 and 3.6 microg/ml, respectively, indicating that propolis showed stronger antagonistic effects as compared with vegetable extracts. PMID: 15118327
its main botanical origin (leaf bud of Baccharis dracunculifolia). suppressive effects of propolis on AhR transformation were relatively higher than those of resins of its botanical origin. propolis contained slightly higher amounts of flavonoid aglycones as compared with its botanical origin with the same characteristics. antiradical activity, one of the typical biological activities of flavonoids, in propolis was also slightly higher than that in its botanical origin. not only propolis but also its botanical origin contains high amounts of flavonoid aglycones and that both of them are useful dietary sources for flavonoids with a potency to prevent dioxin toxicity. PMID: 16366731
Artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) was also identified in both propolis and resinous exudates, and both ethanolic extracts contained the highest concentrations of this compound as compared with the rest of the chemical constituents. PMID: 14995105
delta9-THC completely suppressed the induction of arylhydrocarbon hydroxylase activity of 3-methylcholanthrene from 455% to 177% of control. delta9-THC also inhibited the induction of aminopyrine demethylase by phenobarbital. These drugs do not have any interactive effect on microsomal protein synthesis but are potent antagonists in the synthesis of nuclear RNA. PMID: 996365
After ex vivo exposure to TCDD (a highly potent AhR ligand) for 3 h, Cyp1b1 expression was significantly increased by 2.3-fold in brain microvessels. A single i.p. dose of TCDD also increased Cyp1b1 transcripts (22-fold) and Cyp1b1 protein (2-fold) in rat brain microvessels at 72 h after TCDD. Likewise, DEP treatment (in vivo and ex vivo) strongly induced Cyp1b1 protein in brain microvessels. Diesel exhaust particle-mediated Cyp1b1 induction was inhibited by actinomycin D, cycloheximide, or by an AhR antagonist. In contrast, a sub-chronic in vivo treatment with Δ9-THC once daily for 7 seven days had no effect on Cyp1b1 expression. PMID: 21867498
CBD most potently inhibited catalytic activity of human CYP3A enzymes, especially CYP3A4 and CYP3A5. These results suggest that two phenolic hydroxyl groups in the resorcinol moiety of CBD may play an important role in the CYP3A inhibition. Olivetol partially inhibited all the CYP3A isoforms tested. two phenolic hydroxyl groups in the resorcinol moiety of CBD may play an important role in the CYP3A inhibition. PMID: 21356216
cdc42 expression was increased in comparison to the control cell line. exogenous AhR induced catecholaminergic differentiation. excessive activation of AhR resulted in neural differentiation of Neuro2a cells. This result revealed that dioxins may affect the nervous system through the AhR-signaling pathway. Activated AhR may disrupt the strictly regulated brain formation with irregular differentiation occurring rather than cell death. PMID: 16956419
Induction of TH by TCDD through AhR activation was detected at mRNA and protein levels. Induced TH protein was functional and its expression increased dopamine synthesis. AhR directly regulated TH gene expression. Regulatory sequence called aryl hydrocarbon receptor responsive element III (AHRE-III) was identified upstream of the TH gene from -285 bp to -167 bp. Under TCDD exposure, an AhR complex was bound to AHRE-III as well as the xenobiotic response element (XRE). TCDD directly regulate the dopamine system by TH gene transactivation via an AhR-AHRE-III-mediated pathway. The AhR- mediated pathway could have a particular AhR-mediated genomic control pathway transmitting the effects of TCDD action to target cells in the development of dopaminergic disabilities. PMID: 19500377
Endothelial cells are a target of halogenated aromatic hydrocarbon toxicity. AHR has a physiological function in endothelial cells in the absence of exogenous ligands. crosstalk between hypoxia and AHR in the absence of exogenous ligands. human pulmonary microvascular endothelial cells exposed to hypoxia (1 or 2.5% O2), 25 nM AHR siRNA, 25 nM hypoxia-inducible factor (HIF)-2alpha siRNA, or their combinations. Hypoxia significantly induced known hypoxia-regulated genes, and this induction was highly attenuated by HIF-2alpha siRNA. Hypoxia also significantly reduced CYP1A1 mRNA and this reduction was also attenuated by HIF-2alpha siRNA. As expected, AHR siRNA significantly reduced constitutive CYP1A1 mRNA. While the combination of hypoxia plus AHR siRNA reduced CYP1A1 mRNA more than either treatment alone, the reduction was less than additive, suggesting that hypoxia and AHR deficiency may share a common pathway in reducing CYP1A1 expression. hypoxia significantly reduced AHR mRNA and this reduction was completely prevented by HIF-2alpha siRNA. constitutive CYP1A1 mRNA expression is dependent on AHR and is reduced by hypoxia via a HIF-2alpha-dependent mechanism, which may be mediated by a HIF-2alpha-dependent reduction of AHR expression. PMID: 17968679
AhR antagonist resveratrol (RSV) could reverse this TCDD-induced CYP1A1 expression. both MMP-9 mRNA expression and enzymatic activity were gradually increased with the concentration increase of TCDD in media and these changes could be reversed by RSV treatment in a dose-dependent manner. After TCDD treatment, the migration distance and the migration and invasion abilities of human gastric cancer AGS cells were increased with a dose-dependent manner. MMP-9 mRNA expression and activity in untreated control AGS cells were very weak; After TCDD (10 nmol/L) treatment, MMP-9 mRNA expression and activity were significant increased; This TCDD-induced MMP-9 expression and activity increase could be abolished by c-Jun siRNA transfection. Aryl hydrocarbon receptor pathway activation enhances gastric cancer cell invasiveness likely through a c-Jun-dependent induction of matrix metalloproteinase-9. PMID: 19371443
Aminoflavone (AF), the active component of a novel anticancer agent (AFP464) in phase I clinical trials, is a ligand of the aryl hydrocarbon receptor (AhR). AhR dimerizes with HIF-1beta/AhR, which is shared with HIF-1alpha, a transcription factor critical for the response of cells to oxygen deprivation. To address whether pharmacologic activation of the AhR pathway might be a potential mechanism for inhibition of HIF-1, we tested the effects of AF on HIF-1 expression. AF inhibited HIF-1alpha transcriptional activity and protein accumulation in MCF-7 cells. However, inhibition of HIF-1alpha by AF was independent from a functional AhR pathway. Indeed, AF inhibited HIF-1alpha expression in Ah(R100) cells, in which the AhR pathway is functionally impaired, yet did not induce cytotoxicity, providing evidence that these effects are mediated by distinct signaling pathways. AF was inactive in MDA-MB-231 cells, yet inhibited HIF-1alpha in MDA-MB-231 cells transfected with the SULT1A1 gene. AF inhibited HIF-1alpha mRNA expression by approximately 50%. Notably, actinomycin-D completely abrogated the ability of AF to downregulate HIF-1alpha mRNA, indicating that active transcription was required for the inhibition of HIF-1alpha expression. AF inhibited HIF-1alpha protein accumulation and the expression of HIF-1 target genes in MCF-7 xenografts. AF inhibits HIF-1alpha in an AhR-independent fashion. PMID: 20736373
Cockayne Syndrome group B (CSB) mutant cells are unable to react to hypoxic stimuli by properly activating the hypoxia-inducible factor-1 (HIF-1) pathway, a defect that is further enhanced in the event of a concomitant genotoxic stress. CSB expression is under the control of HIF-1 and has a critical function during hypoxic response by redistributing p300 between HIF-1 and p53. CSB is part of a feedback loop mechanism that modulates the biological functions of p53. PMID: 18784753
intestinal bacteria may contribute to induce inflammation in individuals afflicted by inflammatory bowel disease (IBD), increasing the risk of developing colon cancer. Accumulating evidence suggests that Helicobacter organisms are linked to IBD as well as to gastric and colon cancer. evaluate the effect of lipopolysaccharide (LPS) isolated from Helicobacter on modulating the DNA repair system. We used an in vitro model represented by two colon carcinoma cell lines, the DNA repair-proficient SW480 and the DNA repair-deficient LoVo, and transfected with a UVC-irradiated psV-beta-galactosidase plasmid. We observed that LPS, by upregulating the expression of inducible nitric oxide (NO), leads to an increased NO release, demonstrating that LPS is able to interfere with the DNA repair machinery of intestinal cells, thus increasing the risk of permanent genotoxic effects. PMID: 19651607
treatment of Hepa 1c1c7 cells with maltol significantly induced Cyp1a1 at mRNA, protein, and activity levels in a concentration-dependent manner. The RNA synthesis inhibitor, actinomycin D, completely blocked the Cyp1a1 mRNA induction by maltol, indicating a requirement of de novo RNA synthesis through transcriptional activation. In addition, maltol induced aryl hydrocarbon receptor (AhR)-dependent luciferase reporter gene expression in stably transfected H1L1.1c2 cells, suggesting an AhR-dependent mechanism. This is the first demonstration that the food flavoring agent, maltol, can directly induce Cyp1a1 gene expression in an AhR-dependent manner and represents a novel mechanism by which maltol promotes carcinogenicity and toxicity. PMID: 17317091
Ginkgo biloba extract (GBE) had the strongest inhibitory effect on DEP-induced AhR activation. Quercetin, a major polyphenol in onions, and GBE showed a strong inhibitory effect. PMID: 17622219

endorsing nature

2011-09-02T18:57:00.000-07:00

2011-06-14T16:29:00.000-07:00

http://medicalxpress.com/news/2011-05-worm-discovery-billion-people-worldwide.html
http://en.wikipedia.org/wiki/Trichuris_trichiura Light infestations (<100 worms) are frequently asymptomatic. The female T. trichiura produces 2,000–10,000 single celled eggs per day. Within the United States, infection is rare overall but may be common in the rural Southeast where 2.2 million people are thought to be infected.
Whipworm as a therapeutic agent for IBD and other inflammatory disorders
Main article: Helminthic therapy
The hygiene hypothesis suggests that various immunological disorders that have been observed in humans only within the last 100 years, s...uch as Crohn's disease, or that have become more common during that period as hygienic practices have become more widespread, may result from a lack of exposure to parasitic worms (also called helminths) during childhood. The use of Trichuris suis ova (TSO, or pig whipworm eggs) by Weinstock, et al., as a therapy for treating Crohn's disease[8][9][10] and to a lesser extent ulcerative colitis[11] are two examples that support this hypothesis. There is also anecdotal evidence that treatment of inflammatory bowel disease (IBD) with TSO decreases the incidence of asthma,[12] allergy,[13] and other inflammatory disorders.[citation needed] Some scientific evidence suggests that the course of multiple sclerosis may be very favorably altered by helminth infection;[14] TSO is being studied as a treatment for this disease.[15]
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1440857/ Anti-inflammatory and anti-arthritic effects of yucca schidigera: A review
Palytoxin is a huge molecule with chemical formula C129H223N3O54. http://en.wikipedia.org/wiki/Palytoxin
http://www.oxphos.org/index.php?option=com_content&task=view&id=86&Itemid=1 Succinate in hypoxia
T8690 Thioredoxin human ≥90% (SDS-PAGE), recombinant, expressed in Escherichia coli (N-terminal hist http://www.sigmaaldrich.com/catalog/ProductDetail.do?D7=0&N5=SEARCH_CONCAT_PNO|BRAND_KEY&N4=T8690|SIGMA&N25=0&QS=ON&F=SPEC
http://en.wikipedia.org/wiki/Alanine_cycle
http://groups.google.com/group/alt.baldspot/browse_thread/thread/c3a401892a9be495/c78bfd7536edd801?lnk=gst&q=creatine#c78bfd7536edd801
The increases in serum alanine transaminase levels (after 3 hours and 12 hours of reperfusion) were significantly (P < .01) attenuated in the BH(4) group. http://www.ncbi.nlm.nih.gov/pubmed/16546503 Cytoprotective function of tetrahydrobiopterin in rat liver ischemia/reperfusion injury.
Serum aspartame transaminase may be 15 percent higher in black men than white men.
Plasma homocysteine levels
were increased in all experimental groups from 6 wk onward and
were greatest in FDE. Ethanol feeding reduced liver methionine
synthase activity, S-adenosylmethionine (SAM), and glutathione,
and elevated plasma malondi...aldehyde (MDA) and alanine
transaminase. Folate deficiency decreased liver folate levels and
increased global DNA hypomethylation. Ethanol feeding and folate
deficiency acted together to decrease the liver SAM S-adenosylhomocysteine
(SAH) ratio and to increase liver SAH, DNA strand
breaks, urinary 8-oxo-2 -deoxyguanosine [oxo(8)dG] mg of creatinine,
plasma homocysteine, and aspartate transaminase by more
than 8-fold. Liver SAM correlated positively with glutathione,
which correlated negatively with plasma MDA and urinary
oxo(8)dG. Liver SAM SAH correlated negatively with DNA strand
breaks, which correlated with urinary oxo(8)dG. Livers from
ethanol-fed animals showed increased centrilobular CYP2E1 and
protein adducts with acetaldehyde and MDA.
In summary, the present study demonstrates that the addition
of folate deficiency to a diet containing excessive ethanol both
enhances abnormal hepatic methionine metabolism and promotes
the early development of alcoholic liver injury. Feeding...
the combined FDE diet resulted in the greatest increase in
plasma Hcy and liver SAH levels and the greatest reduction in
the SAM SAH ratio (Table 2), together with an 8-fold increase
in plasma AST.
Vasopressin receptors control fidelity http://groups.google.com/group/sci.med.psychobiology/browse_thread/thread/1d878fcd03ff115b/331820b4dda7d3d?q#0331820b4dda7d3d
http://www.jlaforums.com/viewtopic.php?p=31731514 Endogenous and Exogenous Cannabinoids Modulate Inflammation
Interferon-y Is a Critical Modulator of CB2 Cannabinoid Receptor Signaling during Neuropathic Pain http://www.jneurosci.org/content/28/46/12136.full.pdf

Interferon-y Is a Critical Modulator of CB2 Cannabinoid Receptor Signaling during Neuropathic Pain

2011-06-14T15:13:00.001-07:00

The present results revealed the crucial role of CB2 cannabinoid receptors in the development of neuropathic pain through an immune mechanism linked to modified IFN-activity. Hyperalgesia and allodynia induced by sciatic nerve injury were enhanced in CB2 / mice, as revealed by a mirror image of pain in the contralateral side. These behavioral manifestations of neuropathic pain matched the changes induced in microglial and astrocyte activation, astrocytic IFN-expression, and other biochemical parameters related to the immune response. Glial activators include chemokines that enhance pain sensation and are under the control of immune mediators, as well as several neuromodulators released by nearby neurons, such as prostaglandins (Tanga et al., 2006). Interferons represent crucial modulators of the central and peripheral immune responses (Bach et al., 1997) and the enhanced induction of IFN-genes in CB2 / mice could participate in their nociceptive hypersensitivity. Indeed, a prolonged spinal increase in IFN- levels in inflammatory responses in diseases such as viral infections and multiple sclerosis, is thought to contribute to the associated persistent pain states (Miyazaki et al., 2008). Furthermore, IFN-treatments in cancer therapy can result in spontaneous pain in humans (Quesada et al., 1986; Mahmoud et al., 1992). Intrathecal IFN- administration in mice can also cause pain-related behaviors in normal, but not in IFN-receptor knockout mice (Robertson et al., 1997). Although the molecular and cellular mechanism of interferon-induced pain remains mostly unclear, it has been demonstrated that IFN- can cause spontaneous firing of dorsal horn neurons in vitro and in vivo, as well as enhanced wind-up responses to electrical stimulation (Vikman et al., 2003, 2005, 2007). Interestingly, the pharmacological activation of CB2 cannabinoid receptors suppresses wind-up responses of spinal nociceptive neurons and this effect was more pronounced in the presence of pathological pain (Nackley et al., 2004). The enhanced IFN- response revealed by microarray experiments in CB2 / mice exposed to nerve injury has an important functional relevance in vivo. Thus, a direct relationship between the enhanced IFN- response and the neuropathic pain manifestations of CB2 / mice was demonstrated by using double knock-out animals deficient in CB2 receptors and IFN-. The behavioral phenotype of CB2 / mice showing an enhanced neuropathic pain was completely abolished in these double knock-out animals. IFN- is a crucial modulator of the central and peripheral immune responses suggesting that an immune alteration seems to underline the neuropathic pain responses in CB2 / mice. The manifestations of neuropathic pain observed in CB2 / mice and double knock-out mice deficient in CB2 and IFN- suggest that endocannabinoids play an important role in the control of the immune responses leading to the development of neuropathic pain. In support of this hypothesis, an enhancement in the levels of the two main endocannabinoids, anandamide and 2-arachidonoyl-glycerol, was revealed after sciatic nerve injury in the spinal cord and several brain areas involved in pain, such as the periaqueductal gray matter and the rostral ventral medulla (Petrosino et al., 2007). The endocannabinoid levels were also enhanced after sciatic nerve injury in the dorsal root ganglia (Mitrirattanakul et al., 2006) and the section of the sciatic nerve proximal to the lesion (Agarwal et al., 2007). These increased endocannabinoid levels are likely related to enhanced biosynthesis or decreased catabolism and transport because endocannabinoids are produced on demand without any substantial storage (Di Marzo, 1998). Therefore, endocannabinoids could produce a tonic activation of CB2 receptors after sciatic nerve injury that would limit the immune responses leading to the development of neuropathic pain. In agreement, both mechanical and thermal hyperalgesia produced after sciatic nerve injury were attenuated by the administration of N-arachidonoyl-serotonin, an inhibitor of fatty acid amide hydrolase, the enzyme responsible for the degradation of anandamide (Maione et al., 2007), which further support the role of endocannabinoids in the modulation of neuropathic pain. In contrast with the results here obtained in CB2 / mice, the genetic disruption of the CB1 receptor had no major consequences on the development of neuropathic pain (Castan˜e´ et al., 2006) despite the high expression of these receptors in the CNS (Tsou et al., 1998). However, CB1 receptors expressed in peripheral nociceptors but not in the CNS seem to be involved in the manifestations of neuropathic pain (Agarwal et al., 2007). In agreement, pharmacological activation of CB1 receptors have also been reported to reduce pain sensitivity in a variety of neuropathic pain models (Pertwee, 2005). Subsequent to nerve injury, gradients formed by CCL2 and CCL3 orchestrate the recruitment and activation of resident and monocyte-derived microglia via signaling through their respective receptors CCR2, CCR1, and CCR5 (Scholz and Woolf, 2007). In particular, CCR2 expression in either resident microglia or bone marrow-derived macrophages may be sufficient for the development of mechanical allodynia in a murine neuropathic pain model (Zhang et al., 2007). CB2 cannabinoid receptor activity may critically influence the induction of CCR2 expression by monocytes and thus inhibit their chemotaxis (Steffens et al., 2005). Moreover, endocannabinoids were found to abolish microglia activation by inhibiting NO release through a mechanism linked to the MAPK (mitogen-activated protein kinase) pathway (Eljaschewitsch et al., 2006). Our data revealed that IFN- treatment of mouse BV-2 microglial cells evoked marked microglial activation as indicated by induction of iNOS and CCR2 gene expression. CB2 signaling, however, interfered with the expression of these two IFN--inducible genes in BV-2 cells. These data suggest that CB2 receptor signaling exerts antiinflammatory effects in the neuropathic response by controlling IFN--mediated microglial activation and recruitment. Therefore, these data complement our in vivo observations in the neuropathic response in CB2 / mice. Mice genetically modified either by increasing or eliminating specific gene may be limited by the fact that this genetic change may be affecting not only the target gene but also other biological components, perhaps participating in the effects evaluated in these genetic models. Therefore, pharmacological studies using selective ligands of CB2 receptors would be useful to confirm the relevance of the present results. Nevertheless, these genetic manipulations have been considered a key approach to the identification of alterations associated to different pathological conditions and to the discovering of new potential therapeutic targets in a variety of neuropsychiatric disorders. In this study, the according results obtained in CB2 / mice and double knock-out mice deficient in CB2 and IFN-together with the pharmacological studies performed in vitro further support the relevance of the findings. Our immunofluorescence analysis revealed that IFN-was mainly expressed in neurons after sciatic nerve injury and this expression of IFN-matched the pattern of nociceptive hypersensitivity in all experiments. IFN- expression was also present in astrocytes, but absent in microglia. Previous studies have reported the presence of CB2 receptors in microglial cells (Romero- Sandoval et al., 2008) and neurons (Van Sickle et al., 2005). However, the possible presence of CB2 receptors in neurons and its possible functional role is still a controversial issue that requires additional investigation. Taken all these data into consideration, we can postulate a mechanism to explain the modulation of neuropathic pain through CB2 receptor activation (Fig. 8). Thus, the neuroinflammatory process leading to the development of neuropathic pain seems to be initiated by the microglial activation produced after nerve injury (Scholz and Woolf, 2007). This process requires a coactivation of astrocytes, which, together with neurons, release IFN- and promote consolidation and progression of the neuropathic pain state (Zhang et al., 2007). IFN-promotes microglia activation by the induction of several inflammatory pathways, including an enhancement in iNOS and CCR2 activity. Interestingly, previous studies have reported the expression of IFN- receptors in microglial cells and its modulation under pathological conditions (Cannella and Raine, 2004). CB2 receptors on microglial cells would play a crucial role to control and limit the spreading of this neuroinflammatory process. Thus, the activity of CB2 receptors in microglial cells would reduce the activation of these cells during neuropathic pain by regulating the expression of iNOS and CCR2. In the absence of CB2 receptors, IFN-would produce a more widespread activation of microglial cells, which would enhance the manifestations of neuropathic pain and would be responsible for the presence of a mirror image of pain in the contralateral side.

Thioredoxin Catalyzes the Reduction of Insulin Disulfides by Dithiothreitol and Dihydrolipoamide

2011-06-14T07:06:00.000-07:00

When the two interchain disulfides of insulin are split by reduction, the free B chain will aggregate and precipitate from neutral solutions at low concentration. This well known phenomenon (14) was used in this study to develop a rapid and simple spectrophotometric assay for thiol-mediated protein disulfide reduction. The quantitative relationship between disulfide reduction and the onset of a rate of precipitation was calculated from extrapolation of the rate of NADPH oxidation in the presence of NADPH and thioredoxin reductase as the reducing system for thioredoxin. The two interchain disulfides of insulin are split by thioredoxin at similar rates (5). The K,,, value for insulin with thioredoxin is 11 pM (5). The concentration of insulin in the turbidimetric assay (130 pM) is thus sufficiently high to saturate the thioredoxin-(SH)2 reaction. The main result of this study is the demonstration of thioredoxin as a dithiol-disulfide oxidoreductase that catalyzes the reduction of protein disulfides by dithiothreitol or dihydrolipoamide. Chemically reduced ribonuclease has also been found to be a very efficient dithiol substrate for thioredoxin.’ This result is consistent with a general function of thioredoxin in catalyzing oxidoreduction between suitable dithiols and exposed protein disulfides. The enzymatic mechanism of thioredoxin involves the reduction and oxidation of an exposed active site disulfide bridge (1) with the structure: The disulfide in thioredoxin-S2 and the dithiol in thioredoxin-( SH)z both have unusual reactivities in thiol-disulfide interchange reactions. The second order rate constant for the reduction of thioredoxin by dithiothreitol obtained from the stopped flow fluorescence measurements is compared with measurements by Creighton for model disulfides (19) in Table V. Apparently, thioredoxin-Sz reacts between 2 to 3 orders of magnitude faster at physiological pH values than the model disulfides. Since thioredoxin-(SH)t shows an apparent reactivity with insulin that is around lo4 times higher at pH 7.0 than dithiothreitol (5), the combined effect of these two rates explains the catalytic action of thioredoxin in reducing insulin with dithiothreitol. Thioredoxin-Sz and thioredoxin-(SH)2 may thus be regarded as two species of an enzyme working in a ping-pong reaction. The local conformational change in thioredoxin upon oxidoreduction observed by tryptophan fluorescence (11) and nuclear magnetic resonance spectroscopy(20) explains the differences in reactivity of the two species of thioredoxin. Dihydrolipoamide was a very good dithiol substrate for thioredoxin. This provides a mechanism for NADH-dependent reduction of disulfides to sulfhydryl groups through the operation of lipoamide dehydrogenase. Roman0 and Nickerson (21) have described the existence of a specific NADHdependent cystine reductase (EC 1.6.4.1) or NADH-cystine transhydrogenase in yeast. The cystine reductase activity has not been purified and characterized but could be identical to the combined effect of NADH, lipoamide, lipoamide dehydrogenase, and thioredoxin. Eldjarn and Bremer (22) and Skrede (23) have studied disulfide reduction in mitochondria and shown that reduction of cystamine is NADH and lipoic acid-dependent and occurs by the lipoamide dehydrogenase enzyme in the cY-oxoacid complexes. The studies of Tietze (24) also suggests mitochondria as the place of NADH-dependent disulfide reduction since only NADPH was observed to support this process in 100,OOO X g supernatants of rat liver. Is there any physiological basis for the rapid reaction between dihydrolipoamide and thioredoxin-Sz? Some recent results regarding the functional organization of the pyruvate dehydrogenase complex in E. coli suggest a possible mechanism (25, 26). Lipoic acid is bound in an amide linkage to the dihydrolipoyl transacetylase component of the pyruvate and a-ketoglutarate dehydrogenase multienzyme complexes in E. coli and mitochondria. Studies on the site coupling in electron and acetyl group transfer in the E. coli pyruvate dehydrogenase complex has suggested (26) that only half of the a-lipoyl moieties are coupled to lipoamide dehydrogenase and NADH formation. The other half of the dihydrolipoamide groups may have a yet unidentified electron acceptor (26). Experiments with isolated E. coli pyruvate dehydrogenase complex should decide if this can be thioredoxin. Thioredoxin has been found in mitochondrial preparations from calf liver (27). The coupling between pyruvate decarboxylation and the reduction of thioredoxin may of course represent an unknown substrate cycle. This could operate in cells lacking thioredoxin reductase, as erythrocytes seem to do.3 It should also be noted that a novel role for lipoic acid in oxidative phosphorylation has been suggested recently (28). The fast reduction of thioredoxin-Sz by dihydrolipoamide observed in this study represents the only kinetically favorable reaction between any of the three compounds, lipoic acid, glutathione and thioredoxin. The reduction of the disulfides in these ubiquitous compounds is catalyzed by the three similar but specific dehydrogenases called NADH-lipoamide dehydrogenase, NADPH-glutathione reductase and NADPHthioredoxin reductase. The electrode potentials (E’o values), of the Lip&, GSSG, and thioredoxin-S2 couples are similar or -0.29, -0.25, and -0.26 V, respectively (3). The small molecules GSH and lipoic acid show no particularly rapid thiol-disulfide interchange rates (3). Thioredoxin-Sn is only very slowly reduced by the monothiol GSH (29) nor does thioredoxin-(SH)z react rapidly with GSSG (5). Thioredoxin was originally considered to be a substrate cofactor for the two enzymes thioredoxin reductase and ribonucleotide reductase (30). As shown here, it should rather be regarded as a small disulfide reductase enzyme. This applies for the thioredoxins from E. coli, yeast, and mammalian cells which are homologous proteins2 that all give high activity in the insulin turbidimetric assay.

Glutathionylation of human thioredoxin: A possible crosstalk between the glutathione and thioredoxin systems

2011-06-14T06:54:00.001-07:00

This study shows that Trx can be glutathionylated under conditions of oxidative stress. Glutathionylation was confirmed by incubating rhTrx with GSSG at a concentration (5 mM) that can be observed in vivo under conditions of oxidative stress or in cellular compartments such as the endoplasmic reticulum where the GSH/GSSG ratio can be 1 (22). The mass spectrometric analysis showed that, at a GSSG concentration of 5 mM, only one GSH can be attached to rhTrx at Cys-72. This higher susceptibility of Cys-72 to oxidation is very likely caused by the fact that it is easily accessible in the active site surface of the three-dimensional structure of Trx (23). In fact, when we synthesized peptides reproducing partial Trx sequences and treated them with GSSG, we found that all Cys with the exception of one of those in the CGPC active site were equally susceptible to glutathionylation. Thus the susceptibility of Cys-72 appears to be observed only within the entire protein with its three-dimensional structure. Further supporting the concept that Cys-72 is the Cys residue of rhTrx most exposed to oxidizing agents, we noted that iodoacetamide treatment of rhTrx under nondenaturing conditions alkylated only Cys-72 (data not shown). Alkylation under nondenaturing conditions has been used to determine oxidant-sensitive Cys (also in terms of accessibility in the native structure; refs. 24 and 25). Thus, in the case of Trx, susceptibility to glutathionylation is mainly due to the three-dimensional structure rather than to the chemical-physical properties of the amino acids in the vicinity, as has been suggested for other proteins (26). A glutathione adduct on Cys-72 also might be favored by the primary structure, however, as this amino acid is next to a basic one, Lys-71, which might stabilize the adduct by interacting electrostatically with the -glutamyl group of GSH (27). Interestingly, Cys-72 is also involved in the dimerization of Trx (23, 28), which may occur under oxidative conditions or spontaneous oxidation, confirming that Cys-72 can be easily oxidized. The fact that the same Cys-72 of Trx can be involved in both the dimerization and in the glutathionylation of Trx suggests that glutathionylation prevents dimer formation. In fact, we found that in the absence of GSSG, the mass spectra of rhTrx revealed some Trx dimers, whereas in GSSG-treated rhTrx, no dimer was detectable (data not shown). Analysis by MALDI-TOF of rhTrx exposed to GSSG for longer periods (overnight) showed that two GSH residues can be attached to a single rhTrx molecule. This finding would imply that one of the two Cys that can undergo glutathionylation is Cys-72 and the other is either Cys-61 or Cys-68. In fact, a mixed disulfide between glutathione and one of the Cys of the CGPC active site (Cys-31, Cys-34) would be highly unstable (25). In agreement with this hypothesis, we observed that even when a synthetic peptide containing the CGPC active site was treated with GSSG, no adduct was ever formed with two GSH molecules. The fact that Trx can be glutathionylated raises the question of how this fact affects its activities. We investigated whether glutathionylation affected its enzymatic activity. Glutathionylated rhTrx lost all activity initially, but gradually, the activity was restored with time. This was probably due to the fact that Trx can reduce mixed disulfides (29), though not as efficiently as glutaredoxin, and its residual activity could reactivate itself according to the proposed scheme: The finding that Trx can be regulated by glutathionylation indicates the existence of crosstalk between the glutathione glutaredoxin system and the Trx system through which Trx activity can be influenced by the GSH/GSSG ratio, an indicator of the redox state of the cell. The observation that GSNO also can induce glutathionylation of Trx with the same efficiency as GSSG suggests that, through the formation of GSNO, NO can influence Trx activity. Although we demonstrate the occurrence of Trx glutathionylation in living cells exposed to an exogenous oxidant in the present work, other reports show that S-thiolathion of enzymes, namely glyceraldehyde-3-phosphate dehydrogenase, with loss of enzyme activity, can take place during physiologic oxidative stress such as that induced by monocyte activation (30). Therefore, it will be important to evaluate whether Trx is glutathionylated under pathological conditions resulting in oxidative stress. It should be noted that although glutathionylation reduces the enzymatic activity of Trx, it could have more subtle effects on other activities of this protein, altering its affinity for interacting proteins or even generating new activities. For instance, in a protein related to Trx, sharing its insulin disulfide reducing activity, glycosylation inhibiting factor macrophage migration inhibitory factor, S-thiolation caused conformational changes and generation of a growth factor like bioactivity (31). Trx has many biological activities, whose mechanisms are largely obscure: it acts extracellularly as a cytokine, chemokine, or growth factor (32–34) and intracellularly as a regulatory protein that influences several regulatory proteins such as NF- B (35) and ASK1 (36), and it is efficiently secreted through a still unknown mechanism. The relevance of the posttranslational modification of Trx reported here warrants further investigation.

Synopsis

2011-06-13T09:36:00.000-07:00

http://www.ncbi.nlm.nih.gov/pubmed/17203585 Differential expression of glycans in the hippocampus of rats trained on an inhibitory learning paradigm.
Vicia villosa lectin (VVL) for terminal alpha/beta N-acetylgalactosamine (alpha/beta GalNAc); Galanthus nivalus lectin (GNL) for terminal mannose alpha-1,3 (Man alpha-1,3); Peanut agglutinin (PNA) for galactose beta-1,3N-acetylgalactosamine... (Gal beta-1,3 GalNAc); Erythrina cristagalli lectin (ECL) for galactose beta-1,4 N-acetylglucosamine (Gal beta-1,4 GlcNAc); Sambucus nigra lectin (SNA) for sialic acid alpha-2.6 galactose (SA alpha-2,6 Gal); Maackia amurensis lectin II (MAL II) for sialic acid alpha-2,3 (SA alpha-2,3); Wheat germ agglutinin (WGA) for terminal N-acetylglucosamine with/ without sialic acid (GlcNAc wo SA); succynilated WGA (sWGA) for terminal N-acetylglucosamine without sialic acid (terminal GlcNAc without SA); Griffonia simplicifolia lectin II (GSL II) for terminal alpha/beta N-acetylglucosamine (alpha/beta GlcNAc terminal); and Lotus tetragonolobus lectin (LTL) alpha-fucose
http://www.lifesciencesite.com/lsj/life0801/08_4167life0801_44_51.pdf Molecular Biological and Biochemical Studies on Avian Influenza Virus Receptors in Different Avian Species
http://www.ncbi.nlm.nih.gov/pubmed/19682714 Elderberry flavonoids bind to and prevent H1N1 infection in vitro.
http://www.harvestmoonhealthfoods.com/wyceeljuco12.html Wyldewood Cellars Elderberry Juice Concentrate 12.5 fl. oz $27.99
Oral acute (200 mg/kg) or prolonged (25 mg/kg, every 2 days for 2 weeks) administration of pyritinol significantly reduced streptozotocin-induced changes in free carbonyls, dityrosine, malondialdehyde and advanced oxidative protein products.
http://www.ncbi.nlm.nih.gov/pubmed/18593582 Pyritinol reduces nociception and oxidative stress in diabetic rats. http://www.harvestmoonhealthfoods.com/unnu.html
https://www.greenfoods.com/index.php?main_page=product_info&cPath=1&products_id=11 VEGGIE MAGMA® IS DR. HAGIWARA'S ORIGINAL NUTRIENT-RICH "SALAD IN A GLASS" VEGETABLE BLEND CONTAINING YOUNG BARLEY GRASS JUICE POWDER (GREEN MAGMA) COMBINED WITH 16 NUTRITIOUS VEGETABLES.
http://www.ncbi.nlm.nih.gov/pubmed/20550627 Regulation of markers of synaptic function in mouse models of depression: chronic mild stress and decreased expression of VGLUT1.
http://www.ncbi.nlm.nih.gov/pubmed/20937555 Chronic stress and impaired glutamate function elicit a depressive-like phenotype and common changes in gene expression in the mouse frontal cortex.
Kindling, in the amygdala, is characterized by afterdischarge (AD) activity in the electroencephalogram (EEG) and a progression through five defined seizure stages culminating in generalized seizures. In addition to producing epileptogenisis, studies have linked amygdala kindling to enhanced emotionality in laboratory animals.
http://www.jneurosci.org/content/19/22/RC41.full.pdf Enhanced Amygdala Kindling after Electrical Stimulation of the Ventral Tegmental Area: Implications for Fear and Anxiety
http://www.wikigenes.org/e/gene/e/24949.html
http://science.niuz.biz/dha-t225060.html DHA and uridine enhance synapse formation
http://dx.doi.org/10.1006/dbio.1997.8734 WNT-7a Induces Axonal Remodeling and Increases Synapsin I Levels in Cerebellar Neurons
Lithium mimics WNT-7a in granule cells by inhibiting GSK-3β, a component of the WNT signaling pathway. These results suggest a direct effect of WNT-7a in the regulation of neuronal cytoskeleton and synapsin I in granule cell neurons.
Exercise induces BDNF and synapsin I to specific hippocampal subfields. http://www.ncbi.nlm.nih.gov/pubmed/15079864
The enhancement of stress-related memory by glucocorticoids depends on synapsin-Ia/Ib. http://www.ncbi.nlm.nih.gov/pubmed/20368707
Synapsins differentially control dopamine and serotonin release. http://www.ncbi.nlm.nih.gov/pubmed/20660258
The synapsin cycle: a view from the synaptic endocytic zone. http://www.ncbi.nlm.nih.gov/pubmed/17455288
http://www.ncbi.nlm.nih.gov/pubmed/16373512 Protein fucosylation regulates synapsin Ia/Ib expression and neuronal morphology in primary hippocampal neurons.
http://dx.doi.org/10.1016/j.ymgme.2005.11.016 Metabolic changes associated with hyperammonemia in patients with propionic acidemia
http://www.additivesinfood.info/codes/282/ calcium propionate (Preservative E282)
Propionyl CoA is formed as a product of beta-oxidation of odd-chain fatty acids.
http://library.med.utah.edu/NetBiochem/FattyAcids/9_4c.html
http://en.wikipedia.org/wiki/Vasopressin http://en.wikipedia.org/wiki/Biotin
http://en.wikipedia.org/wiki/Avidin
http://www.weizmann.ac.il/Biological_Chemistry/scientist/Bayer/new_pages/reserch_topics/avidin_biotin.html
Biocytin hydrazide (BCHZ), a new, water-soluble, long-chained, biotin-containing hydrazide, was synthesized and used for the selective nonradioactive detection of glycoconjugates.
http://www.ncbi.nlm.nih.gov/pubmed/12855812 5-HT4(a) receptors avert opioid-induced breathing depression without loss of analgesia.
http://jb.oxfordjournals.org/content/143/6/719.abstract Expression and Function of the HNK-1 Carbohydrate
http://www.jbc.org/content/274/36/25608.full Structure and Function of HNK-1 Sulfotransferase IDENTIFICATION OF DONOR AND ACCEPTOR BINDING SITES BY SITE-DIRECTED MUTAGENESIS
http://en.wikipedia.org/wiki/B3GAT1
http://jcb.rupress.org/content/115/3/731.full.pdf Developmentally and Spatially Regulated Expressio of HNK1 Carbohydrate Antigen on a Novel Phosphatidylinositol-anchored Glycoprotein in Rat Brain
http://www.ncbi.nlm.nih.gov/pubmed/21604096 Inhibition of the bacterial lectins of Pseudomonas aeruginosa with monosaccharides and peptides.
The major source of acquisition of P. aeruginosa appears to be from the environment.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2671200/ http://www.invitrogen.com/site/us/en/home/References/Molecular-Probes-The-Handbook/Probes-for-Cytoskeletal-Proteins/Probes-for-Tubulin-and-Other-Cytoskeletal-Proteins.html
http://www.ncbi.nlm.nih.gov/pubmed/19253034 The molecular architecture of ribbon presynaptic terminals.
http://www.ncbi.nlm.nih.gov/pubmed/21187649 2-Decenoic acid ethyl ester possesses neurotrophin-like activities to facilitate intracellular signals and increase synapse-specific proteins in neurons cultured from embryonic rat brain.
http://www.glaserorganicfarms.com/shop/index.php?l=product_detail&p=21
http://www.easycart.net/BeyondACenturyInc./Special_Products_A-G.html Cococin Powder 5th from the bottom
http://www.florida-coconuts.com/produtos.php
http://store.vitacoco.com/v/cart.aspx?ID=241&Q=1&S=8 Green Young Coconut Water
www.glaserorganicfarms.com Organic green young coconut water.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2895317/ Exogenous thioredoxin prevents ethanol-induced oxidative damage and apoptosis in mouse liver
http://www.ncbi.nlm.nih.gov/pubmed/16439183 A dual effect of N-acetylcysteine on acute ethanol-induced liver damage in mice. http://www.ncbi.nlm.nih.gov/pubmed/17548252 N-acetylcysteine inhibits activation of toll-like receptor 2 and 4 gene expression in the liver and lung after partial hepatic ischemia-reperfusion injury in mice
http://www.ncbi.nlm.nih.gov/pubmed/19576882 Melatonin protects against alcoholic liver injury by attenuating oxidative stress, inflammatory response, and apoptosis
http://www.ncbi.nlm.nih.gov/pubmed/14713338 Intravenous administration of thioredoxin decreases brain damage following transient focal cerebral ischemia in mice
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2693936/ Regulation of Thioredoxin by Ceramide in Retinal Pigment Epithelial Cells
Increased glucocorticoid production and sensitivity with advancing age decrease skeletal hydration and thereby increase skeletal fragility by attenuating the volume of the bone vasculature and interstitial fluid.
http://www.unil.ch/webdav/site/dbcm/shared/riederer/CurrentProteomics2009_Riederer.pdf
http://en.wikipedia.org/wiki/Posterior_column-medial_lemniscus_pathway
http://en.wikipedia.org/wiki/Clarke%27s_nucleus
http://en.wikipedia.org/wiki/FAD
http://www.ajcn.org/content/75/4/616.full High-dose vitamin therapy stimulates variant enzymes with decreased coenzyme binding affinity (increased Km): relevance to genetic disease and polymorphisms
http://en.wikipedia.org/wiki/Nicotinamide Molecular formula C6H6N2O
http://www.ncbi.nlm.nih.gov/pubmed/16734417 Artemin crystal structure reveals insights into heparan sulfate binding. http://www.ncbi.nlm.nih.gov/pubmed/21619614 Inhibition of TRPA1 channel activity in sensory neurons by the glial cell line-derived neurotrophic factor family member, artemin.
http://www.ncbi.nlm.nih.gov/pubmed/19845789 Distribution of artemin and GFRalpha3 labeled nerve fibers in the dura mater of rat: artemin and GFRalpha3 in the dura.
Genomic organization of the human SPOCK gene and its chromosomal localization to 5q31. http://www.ncbi.nlm.nih.gov/pubmed/9545645 http://www.ncbi.nlm.nih.gov/pubmed/11131125 Distribution of testican expression in human brain.
http://www.ncbi.nlm.nih.gov/pubmed/10386950 Molecular cloning of testican-2: defining a novel calcium-binding proteoglycan family expressed in brain.
http://www.ncbi.nlm.nih.gov/pubmed/17920205 Mesencephalic dopamine neuron number and tyrosine hydroxylase content: Genetic control and candidate genes.
http://www.ncbi.nlm.nih.gov/pubmed/9181134 Cloning of testican/SPOCK in man and mouse. Neuromuscular expression perspectives in pathology.
An osteonectin-like domain, a Kazal-like sequence and a 46-amino-acid motif around a Cys-Trp-Cys-Val peptide encountered in cell-surface antigens, cell-adhesion molecules and growth-factor-binding proteins are distributed within the testican protein core.
Testican has been shown to carry substantial amounts of chondroitin sulfate as well as other oligosaccharides, but the biological significance of these embellishments is not yet known. http://www.ncbi.nlm.nih.gov/pubmed/7952652 The role of thiol proteases in tissue injury and remodeling. Human proteoglycan testican-1 inhibits the lysosomal cysteine protease cathepsin L. http://www.ncbi.nlm.nih.gov/pubmed/14511383
http://www.ncbi.nlm.nih.gov/pubmed/21490396 Heparanase powers a chronic inflammatory circuit that promotes colitis-associated tumorigenesis in mice.
http://www.ncbi.nlm.nih.gov/pubmed/21408198 Modulation of brain β-endorphin concentration by the specific part of the Y chromosome in mice.
http://www.ncbi.nlm.nih.gov/pubmed/18581056 Sex determination in mammals--before and after the evolution of SRY.
http://www.ncbi.nlm.nih.gov/pubmed/21183788 Identification of SOX3 as an XX male sex reversal gene in mice and humans.
Effect of brain monoamine precursors on stress-induced behavioral and neurochemical changes in aged mice http://dx.doi.org/10.1016/0006-8993(84)90514-6
http://www.molecularbrain.com/content/2/1/8 Tryptophan 2,3-dioxygenase is a key modulator of physiological neurogenesis and anxiety-related behavior in mice
http://www.ncbi.nlm.nih.gov/pubmed/20099004 The impact of taurine- and beta-alanine-supplemented diets on behavioral and neurochemical parameters in mice: antidepressant versus anxiolytic-like effects.
http://www.ncbi.nlm.nih.gov/pubmed/21590285 Antidepressant-like effect of artemin in mice: a mechanism for acetyl-L: -carnitine activity on depression.
http://www.ncbi.nlm.nih.gov/pubmed/20302919 Acetyl-L-carnitine increases artemin level and prevents neurotrophic factor alterations during neuropathy.
Endogenous cannabinoid signaling is required for voluntary exercise-induced enhancement of progenitor cell proliferation in the hippocampus. http://www.ncbi.nlm.nih.gov/pubmed/19489006 Endocannabinoids and voluntary activity in mice: runner's high and long-term consequences in emotional behaviors. http://www.ncbi.nlm.nih.gov/pubmed/20353785
CB1 receptor deficiency decreases wheel-running activity: consequences on emotional behaviours and hippocampal neurogenesis. http://www.ncbi.nlm.nih.gov/pubmed/20138171
http://faculty.psy.ohio-state.edu/wenk/documents/MolecPsych142009.pdf Cannabinoid agonist WIN-55,212-2 partially restores neurogenesis in the aged rat brain
http://brainmeta.com/forum/index.php?showtopic=5398
As synapsin I is a presynaptic protein, its increase in CA1 dendritic layers may indicate synaptogenesis and neural reorganization, possibly induced by activity relayed from the DG through transsynaptic circuitry from the DG to CA1. In conclusion, physiologic levels of activity produced by exercise increase BDNF and synapsin I levels to specific hippocampal subfields, indicating activation of specific hippocampal circuitry, which may include a spatial restriction on BDNF-mediated regulation of synapsin I. This ability of BDNF to mediate exercise-induced hippocampal synaptic plasticity by regulating synapsin I in specific hippocampal subfields may underlie the improved neural function seen with exercise.
http://dx.doi.org/10.1016/0006-291X(92)90507-H The reducing activity of S-aminoethylcysteine ketimine and similar sulfur-containing ketimines
http://www.ncbi.nlm.nih.gov/pubmed/17727797 Protective effects of tungstophosphoric acid and sodium tungstate on chemically induced liver necrosis in wistar rats.
http://www.caymanchem.com/app/template/Article.vm
http://www.caymanchem.com/app/template/Article.vm/article/2138
http://nutritiondata.self.com/
http://www.sciencedaily.com/releases/2010/07/100714104059.htm Tea May Contain More Fluoride Than Once Thought, Research Shows
http://www.ncbi.nlm.nih.gov/pubmed/8961242
http://www.ncbi.nlm.nih.gov/pubmed/21284844
Selective gamma-hydroxybutyric acid receptor ligands increase extracellular glutamate in the hippocampus, but fail to activate G protein and to produce the sedative/hypnotic effect of gamma-hydroxybutyric acid. http://www.ncbi.nlm.nih.gov/pubmed/14535954
http://lib.bioinfo.pl/pmid:15952782 http://lib.bioinfo.pl/pmid:15964843 http://lib.bioinfo.pl/pmid:16157695 http://lib.bioinfo.pl/pmid:8636122
The first and second internal loop regions of the cannabinoid CB1 receptor were involved in transducing the pathway leading to luciferase gene expression. http://lib.bioinfo.pl/pmid:10422789
http://www.ncbi.nlm.nih.gov/pubmed/15952782 Cysteine residues in the human cannabinoid receptor: only C257 and C264 are required for a functional receptor, and steric bulk at C386 impairs antagonist SR141716A binding.
http://www.ncbi.nlm.nih.gov/pubmed/20025243 Hydrophobic residues in helix 8 of cannabinoid receptor 1 are critical for structural and functional properties.
Our results are congruent with a hypothesis that anandamide approaches its binding site by laterally diffusing within one membrane leaflet in an extended conformation and interacts with a hydrophobic groove formed by helices 3 and 6 of CB1, where its terminal carbon is positioned close to a key cysteine residue in helix 6 leading to receptor activation.
http://www.ncbi.nlm.nih.gov/pubmed/18509622 CB(1) cannabinoid receptor activation dose dependently modulates neuronal activity within caudal but not rostral song control regions of adult zebra finch telencephalon.
http://www.ncbi.nlm.nih.gov/pubmed/21645625
Dissociable systems of working memory for rhythm and melody.
http://www.ncbi.nlm.nih.gov/pubmed/21642004 DISC1 is associated with cortical thickness and neural efficiency.
http://www.ncbi.nlm.nih.gov/pubmed/19650139 Impact of schizophrenia-risk gene dysbindin 1 on brain activation in bilateral middle frontal gyrus during a working memory task in healthy individuals.
http://www.ncbi.nlm.nih.gov/pubmed/20827271 Gamma oscillatory power is impaired during cognitive control independent of medication status in first-episode schizophrenia.
http://www.ncbi.nlm.nih.gov/pubmed/19568482 Emotion-elicited gamma synchrony in patients with first-episode schizophrenia: a neural correlate of social cognition outcomes.
http://www.ncbi.nlm.nih.gov/pubmed/21308001 Hippocampal oscillations in the rodent model of schizophrenia induced by amygdala GABA receptor blockade.
http://www.ncbi.nlm.nih.gov/pubmed/21281651 Control of hippocampal theta rhythm by serotonin: Role of 5-HT2c receptors.
http://www.mezziah.org/transhuman/personal/piracetam_raw.htm
http://lib.bioinfo.pl/paper:17369910
http://lib.bioinfo.pl/find?field=Papers&query=cysteine+cb1
http://www.newworldwinemaker.com/articles/view?id=340
http://www.benbest.com/health/alcohol.html
http://www.quantium.plus.com/lr/lr91.htm LONGEVITY REPORT 91
http://schizophreniabulletin.oxfordjournals.org/content/2/1/90.full.pdf
A review of recent studies of the biosynthesis and excretion of hallucinogens formed by methylation of neurotransmitters or related substances
http://www.ncbi.nlm.nih.gov/pubmed/18930743 Excessive S-adenosyl-L-methionine-dependent methylation increases levels of methanol, formaldehyde and formic acid in rat brain striatal homogenates: possible role in S-adenosyl-L-methionine-induced Parkinson's disease-like disorders.
The spiral ganglion: Connecting the peripheral and central auditory systems
http://dx.doi.org/10.1016/j.heares.2011.04.003
Cholinergic systems mediate action from movement to higher consciousness http://dx.doi.org/10.1016/j.bbr.2009.12.046
Induction of innate immune genes in brain create the neurobiology of addiction http://dx.doi.org/10.1016/j.bbi.2011.03.003
http://www.nature.com/npp/journal/v30/n9/full/1300711a.html Neuropsychopharmacology - Behavioral Tolerance to Lysergic Acid Diethylamide is Associated with Redu
Neuropsychopharmacology, the official publication of the American College of Neuropsychopharmacology, publishing the highest quality original research and advancing our understanding of the brain and behavior.
http://www2.ups.edu/faculty/amadlung/Plant_Phys_Bio332/Bio332_04_GMOdigestion.pdf Assessing the survival of transgenic plant DNA in the human gastrointestinal tract
http://www.ncbi.nlm.nih.gov/pubmed/20223226
http://brainmaps.org/index.php?pm=medial+habenula
http://www.ncbi.nlm.nih.gov/pubmed/9030340
http://www.ncbi.nlm.nih.gov/pubmed/21626599
http://www.ncbi.nlm.nih.gov/pubmed/15931590 http://www.ncbi.nlm.nih.gov/pubmed/21596542 http://www.ncbi.nlm.nih.gov/pubmed/21480794
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0002082
http://www.isteroids.com/steroids/Trenbolone-Acetate-Finaplix.html
http://www.raysahelian.com/aromatase.html
http://www.raysahelian.com/chrysin.html
http://www.ncbi.nlm.nih.gov/pubmed/20813161 http://www.ncbi.nlm.nih.gov/pubmed/21625419 http://www.ncbi.nlm.nih.gov/pubmed/21603032 http://www.ncbi.nlm.nih.gov/pubmed/21550230 http://www.ncbi.nlm.nih.gov/pubmed/20981159
http://forums.rxmuscle.com/archive/index.php/t-27222.html
http://www.ncbi.nlm.nih.gov/pubmed/21531755
http://www.ncbi.nlm.nih.gov/pubmed/21466813
http://www.ncbi.nlm.nih.gov/pubmed?term=chrysin
http://dx.doi.org/10.1016/j.toxlet.2011.03.023 Arsenic and fluoride induce neural progenitor cell apoptosis
http://brainmaps.org/index.php?pm=hyperstriatum+ventrale
Furthermore, activation of nicotinic acetylcholine receptor (nAChR)-α3 and -α7 and whether a PPARγ agonist, rosiglitazone (RGZ), blocks nicotine-mediated Wnt activation were examined. Following nicotine stimulation, there was clear evidence for nAChR-α3 and -α7 up-regulation, accompanied by the activation of PKC and Wnt signaling, which was further accompanied by significant changes in the expression of the downstream targets of Wnt signaling at 24 hours. Nicotine-mediated Wnt activation was almost completely blocked by pretreatment with either calphostin C or RGZ, indicating the central involvement of PKC activation and Wnt/PPARγ interaction in nicotine-induced up-regulation of Wnt signaling, and hence AIF-to-MYF transdifferentiation, providing novel preventive/therapeutic targets for nicotine-induced lung injury.
http://en.wikipedia.org/wiki/Adenosine
http://www.ncbi.nlm.nih.gov/pubmed/21616118 Anterior cingulate proton spectroscopy glutamate levels differ as a function of smoking cessation outcome.
http://www.ncbi.nlm.nih.gov/pubmed/12450963 Caudate nucleus volumes and genetic determinants of homocysteine metabolism in the prediction of psychomotor speed in older persons with depression.
http://jcem.endojournals.org/content/early/2011/05/18/jc.2011-0226.short Metyrapone Administration Reduces the Strength of an Emotional Memory Trace in a Long-Lasting Manner
jcem.endojournals.org
Context: It has recently been demonstrated that the process of memory retrieval serves as a reactivation mechanism whereby the memory trace that is reactivated during retrieval is once again sensitive to modifications by environmental or pharmacological manipulations.
http://www.odh.ohio.gov/pdf/idcm/ehrl.pdf Non-lyme tick-borne pathogens
http://www.ncbi.nlm.nih.gov/pubmed/21615557
Chondroitin sulfate proteoglycans regulate astrocyte-dependent synaptogenesis and modulate synaptic activity in primary embryonic hippocampal neurons.
Homer 1a gates the induction mechanism for endocannabinoid-mediated synaptic plasticity. http://www.ncbi.nlm.nih.gov/pubmed/20181604
http://www.ncbi.nlm.nih.gov/pubmed/19274064 PSD-95 regulates D1 dopamine receptor resensitization, but not receptor-mediated Gs-protein activation.
http://www.ncbi.nlm.nih.gov/pubmed/17369255 Inhibition of the dopamine D1 receptor signaling by PSD-95.
http://www.jneurosci.org/content/29/22/7124.full.pdf PSD-95 Is Essential for Hallucinogen and Atypical Antipsychotic Drug Actions at Serotonin Receptors
Given the accumulating evidence that hallucinogenic action involves alterations in synaptic activity, our data further suggest the possibility that hallucinogens may exert their actions via PSD-95-mediated interactions with glutamatergic signaling complexes downstream of 5-HT2A receptor activation.
http://www.chinaphar.com/1671-4083/25/176.pdf Membrane associated Guanylate Kinase superfamily of proteins
http://thebiogrid.org/8573/publication/nuclear-translocation-and-transcription-regulation-by-the-membrane-associated-guanylate-kinase-casklin-2.html
http://www.ncbi.nlm.nih.gov/pubmed/19118122
THC (1 microM) inhibited excitatory postsynaptic currents (EPSCs) and whole-cell I(Ca) evoked at 0.1 Hz but at 0.5 Hz THC had little effect. Modulation of excitatory synaptic transmission by Delta 9-tetrahydrocannabinol switches from agonist to antagonist depending on firing rate.
http://stke.sciencemag.org/content/vol0/issue2003/images/data/CMP_13010/DC1/MammalianPathway-Final.swf
http://stke.sciencemag.org/cgi/content/full/sigtrans;CMP_13010/DC1
http://www.ncbi.nlm.nih.gov/pubmed/21525926
http://dx.doi.org/10.1016/j.bbr.2010.11.039 The cholinergic system, circadian rhythmicity, and time memory
http://en.wikipedia.org/wiki/Cryptochrome
Cryptochrome - Wikipedia, the free encyclopedia
en.wikipedia.org
Cryptochromes (from the Greek κρυπτό χρώμα, hidden colour) are a class of blue light-sensitive flavoproteins found in plants and animals. Cryptochromes are involved in the circadian rhythms of plants and animals, and in the sensing of magnetic fields in a number of species.
http://dx.doi.org/10.1016/j.legalmed.2011.03.001
Recent evidence from Arabidopsis thaliana cryptochrome also suggests that radical pairs can be generated by the light-independent dark reoxidation of Flavin protein by molecular oxygen through the formation of a spin-correlated FADH-superoxide radical pairs.[44] Magnetoception is hypothesized to function through the surrounding magnetic fields effect on the correlation (parallel or anti-parallel) of these radicals, which affects the duration that cryptochrome remains activated. Activation of cryptochrome may affect the light-sensitivity of retinal neurons, with the overall result that the animal can "see" the magnetic field.
http://en.wikipedia.org/wiki/Cocaine_and_amphetamine_regulated_transcript
Cocaine and amphetamine regulated transcript - Wikipedia, the free encyclopedia
en.wikipedia.org
Cocaine and amphetamine regulated transcript also known as CART is a protein that in humans is encoded by the CARTPT gene.[1][2] CART appears to have roles in reward, feeding, and stress, and it has the functional properties of an endogenous psychostimulant.[3]
http://dx.doi.org/10.1016/j.bbr.2011.03.067
Neuropeptide Y (NPY) is one of the most abundant peptides in the central nervous system and currently there are four known receptor subtypes Y1, Y2, Y4 and Y5. Central NPY and its receptors have been implicated in a variety of physiological processes such as epilepsy, sleep, obesity, learning and memory, gastrointestinal regulation, alcoholism, depression and anxiety. The localization of these receptors within the brain is consistent with the roles mentioned, as they are found in varying density within the limbic structures, such as the hippocampal formation, amygdala, hypothalamus and septum. It is well understood that NPY produces anxiolytic responses following central administration under stressful or anxiety-provoking situations. In contrast, central administration of the neuropeptide corticotropin-releasing factor (CRF) produces anxiogenic behaviors. It has been proposed that NPY counteracts the effects of CRF to maintain no net change in emotional state, e.g., emotional homeostasis. In this article, we review the scientific literature describing the NPY–CRF relationship, specifically as it relates to the modulation of the CRF-mediated stress responses via the amygdala, a key forebrain structure involved in the regulation of emotional state.
http://www.iicb.res.in/divisionwiselistofscientists/dddb/allpub_nirmald.html
http://dx.doi.org/10.1016/S0076-6879(05)91003-3
http://www.nature.com/bjc/journal/v80/n10/abs/6690558a.html
http://www.sciencedaily.com/releases/2011/05/110523101948.htm
http://www.nature.com/nm/journal/vaop/ncurrent/full/nm.2387.html
http://stke.sciencemag.org/cgi/content/abstract/sigtrans;4/167/ra20?view=abstract
What doesn't kill the brain makes it stronger
www.sciencedaily.com
Scientists say that a newly discovered "survival protein" protects the brain against the effects of stroke in rodent brain tissue by interfering with a particular kind of cell death that's also implicated in complications from diabetes and heart attack.
http://dx.doi.org/10.1016/j.ejphar.2009.01.025 Effect of δ-9-tetrahydrocannabinol on altered antioxidative enzyme defense mechanisms and lipid peroxidation in mice testes
http://members.iowatelecom.net/sharkhaus/marijuana_melatonin.html Is It Okay To Use Marijuana To Get To Sleep melatonin levels increase by 400 percent
members.iowatelecom.net
Medical marijuana and melatonin
http://www.health101.org/art_methylcobalamin.htm
http://www.enzymatictherapy.com/Products/Energy/Daily-Energy/05623-B12-Infusion.aspx
http://www.ncbi.nlm.nih.gov/pubmed/21241747
http://brainmind.com/CaudateHead.html
http://www.pureendurance.net/lactic_acid
http://dx.doi.org/10.1016/j.biopsych.2010.12.006
http://dx.doi.org/10.1016/j.neurobiolaging.2011.03.002
http://dx.doi.org/10.1016/0091-3057(80)90146-X
http://dx.doi.org/10.1016/S0304-3940(99)00406-1
http://dx.doi.org/10.1016/S0165-1838(98)00134-9
http://www.ncbi.nlm.nih.gov/pubmed/21331438
http://www.ncbi.nlm.nih.gov/pubmed/21540999
http://www.ncbi.nlm.nih.gov/pubmed/20388714
http://abstractboard.com/pubmedDetail.php?id=10657232
http://www.inchem.org/documents/jecfa/jecmono/v35je03.htm
834. Butyllhydroquinone, tert- (WHO Food Additives Series 35)
www.inchem.org
http://www.nature.com/mp/journal/v5/n1/full/4000589a.html The role of stress in the pathophysiology of the dopaminergic system
www.nature.com
Molecular Psychiatry publishes work aimed at elucidating biological mechanisms underlying psychiatric disorders and their treatment
http://www.ncbi.nlm.nih.gov/pubmed/19489006 Endogenous cannabinoid signaling is required for voluntary exercise-induced enhancement of progenitor cell proliferation in the hippocampus
http://www.dadamo.com/protocols/17.html
http://www.dadamo.com/
http://www.battleforhealth.com/Battle_for_Health/Agglutination.html
Agglutination
www.battleforhealth.com
Agglutination literally means “glued together”. This is what happens to your red blood cells when they are exposed to lectins. Note the left side is a picture of healthy cells, and the right side is a mass of cells clumped together.
Calcium dipicolinate also caused spores irradiated in the presence of iodoacetamide to germinate and therefore evidently by-passed the damaged germination mechanism. http://mic.sgmjournals.org/cgi/reprint/64/3/301.pdf
Up to 20% of the dry weight of the endospore consists of calcium dipicolinate within the core, which is thought to stabilize the DNA. Dipicolinic acid could be responsible for the heat resistance of the spore.
http://glycob.oxfordjournals.org/content/19/12/1382.full Metabolic glycoengineering: Sialic acid and beyond
glycob.oxfordjournals.org
This report provides a perspective on metabolic glycoengineering methodology developed over the past two decades that allows natural sialic acids to be replaced with chemical variants in living cells and animals. Examples are given demonstrating how this tec
http://www.harmreductionjournal.com/content/2/1/17 Harm reduction-the cannabis paradox
www.harmreductionjournal.com
This article examines harm reduction from a novel perspective. Its central thesis is that harm reduction is not only a social concept, but also a biological one. More specifically, evolution does not make moral distinctions in the selection process, but utilizes a cannabis-based approach to harm red
http://dx.doi.org/10.1016/0300-483X(88)90128-X Choleresis and increased biliary efflux of glutathione induced by phenolic antioxidants in rats
Role of astroglia and insulin-like growth factor-I in gonadal hormone-dependent synaptic plasticity. http://www.ncbi.nlm.nih.gov/pubmed/9370220
Changes in axonal transport could be an important mechanism of disordering the growth of neurons and innervated cells in old age. Age-related changes in axonal transport. http://www.ncbi.nlm.nih.gov/pubmed/9315448 Exp Gerontol. 1997 Jul-Oct;32(4-5):441-50.
Small doses of sodium fluoride accelerated axonal transport, and this correlated with a rise in cAMP levels in ventral roots of the spinal cord. Following irradiation hormonal effects on axonal transport changed, for example, the stimulatory effect of estradiol became weak, especially in old rats.
It was also shown that hydrocortisone and testosterone were transported along axons, reached fibers of the skeletal muscles, and hyperpolarized the plasma membrane.
Theralac, 30 capsules
www.lef.org
Theralac's breakthrough technology guarantees 100 percent live delivery of its probiotics into the intestinal tract. Once in the gut, Theralac's strains are stimulated into action by LactoStim, a patented prebiotic that feeds probiotics. Rapid colonization of intestinal surfaces follows and bowel mo
http://www.controlyourimpact.com/articles/antiperspirant-aluminum-and-alzheimers-disease/
http://www.raven1.net/mcf/gwen-haarp-satellite-gps-emf-control-grid.htm
http://idsn.org/news-resources/idsn-news/read/article/the-cost-of-cotton-every-30-minutes-an-indian-farmer-commits-suicide/128/
International Dalit Solidarity Network: The cost of cotton - Every 30 minutes an Indian farmer commi
idsn.org
The report, Every Thirty Minutes: Farmer Suicides, Human Rights, and the Agrarian Crisis in India, released by the Center for Human Rights and Global Justice (CHRGJ) and the The International Human Rights Clinic (IHRC) looks critically at India’s farmer suicide epidemic. A quarter of a million India
16 years = 504 million seconds / 250,000 suicides = 1 suicide per 2016 seconds/ 33.6 minutes
http://www.nature.com/labinvest/journal/v83/n2/full/3780603a.html Matrix Metalloproteinase Production by COOH-Terminal Heparin-Binding Fibronectin Fragment in Rheumatoid Synovial Cells
The level of sialic acid residues in platelets was found to be significantly lower and the carbonylation of proteins was higher in old age, diabetes, and lymphoma cases in comparison to controls. The level of carbonylation correlated with desialylation in these cases. In vitro treatment of platelets with free radicals was found to cause desialylation and to increase the carbonyl content.
Sialic acids are biosynthesized by almost all organisms as a 9-carbon carboxylated monosaccharide and are integral components of glycoconjugates.
Ethanol, given IP at 2 g/kg, seemed to decrease total SA in all brain regions at four hours after injection, with statistically significant decreases in the hippocampus and brainstem. With 3 g/kg, only the cerebellum showed a 25% decrease at four hours.
Only identical twins have chemically identical glycocalices; everyone else is unique.
More than 40 naturally occurring sialic acid derivatives of the three main forms of sialic acids, the N-acetyl- and N-glycolylneuraminic acid and 2-keto-3-deoxy-nonulosonic acid have been identified.
Gangliosides being amphiphilic sialic acid containing glycosphingolipids, are highly accumulated in complex in synaptic membranes assumed to fulfill the task of neuromodulators in connection with calcium by transmission and storage of information.
Virtually all cell surface proteins and many cell membrane lipids are glycosylated, creating a cell surface glycocalyx. The glycan chains attached to cell surface glycoproteins and glycolipids are complex structures with specific additions that determine functions of the glycans in cell–cell communication and cell sensing of the environment. Glycans can decorate glycan termini by sialic acids.
Thus, our studies clearly show that chronic ethanol induced deglycosylation of brain gangliosides is in part, due to specific up-regulation of plasma membrane sialidase in the myelin and synaptosomal membrane fractions of the brain.
This increase in plasma membrane sialidase may be responsible for chronic-ethanol-induced physiological and neurological impairment in the brain, presumably due to deglycosylation of gangliosides that are essential for crucial cellular and metabolic activities.
The data in the present study indicate that COC administration may modify constitutive synaptic plasticity in the mPFC by increasing the NCAM polysialylation in perisomatic innervations of pyramidal neurons via activation of dopamine D1 and D2/D3 receptors.
An acute cocaine injection increases the mRNA level of polysialyltransferase ST8SiaII. Cocaine administration leads to an enhancement of PSA-NCAM protein expression. An increase in the PSA-NCAM protein is mainly observed in the perisomatic-like sites. Inhibition of D1 or D2 dopamine receptors abolishes effects of cocaine administration.
Chronic stress and corticosterone decreased sialidase activity in the brain homogenates and synaptosomes. In the stressed animals, these changes were related to significantly higher expression of polysialic acid. Sialidase activity caused by stress and chronic corticosterone administration reflect disturbances of polysialylated glycoconjugates known to be related to synaptic plasticity in hippocampus.
Testicular hormones confer resiliency to chronic stress in males therefore reducing the likelihood of developing putative physiological, behavioural or neurological depressive-like phenotypes.
http://www.springerlink.com/content/bw2551j407l1524w/
Possible mechanisms whereby fluoride could affect brain function include influencing calcium currents, altering enzyme configuration by forming strong hydrogen bonds with amide groups, inhibiting cortical adenylyl cyclase activity and increasing phosphoinositide hydrolysis.
http://dx.doi.org/10.1016/j.neuroscience.2011.03.048
http://engineering.colorado.edu/news/CUE/2008/features/mech.htm
http://dx.doi.org/10.1016/j.jad.2010.11.005
http://dx.doi.org/10.1016/j.cellsig.2010.08.011
When mice behavior was assessed in a cross maze, those fed the lowest and mid-level fish-containing diets developed higher anxiety state behaviors compared to mice fed with control diet. The 0.1% (5ng/d) fish-containing regimen proved to affect gene expression, muscle mitochondrial respiration, and triggered an anxiety-driven behavior in mice.
The level of mercury in rain ranged from 1.3 to 81.2 nanograms per liter
Cigarette smoke contains up to 11.5 nanograms of mercury per cigarette in mainstream smoke and up to 16.6 nanograms of mercury per cigarette in side stream smoke. Mitochondrial respiratory rates showed a 35-40% decrease in respiration for the three contaminated mice groups. In the muscles of mice fed the lightest fish-containing diet, cytochrome c oxidase activity was decreased to 45% of that of the control muscles
http://groups.google.com/group/sci.life-extension/browse_thread/thread/1da1d8a1a75e0309/e2a82f5cdf7c3667?q#e2a82f5cdf7c3667
Magnesium and DNA repair - sci.life-extension | Google Groups
groups.google.com
1. Magnesium chloride, magnesium aspartate, magnesium gluconate, and magnesium lactate are better tolerated than magnesium oxide.
http://groups.google.com/group/sci.life-extension/browse_thread/thread/159949aa0417e215/fe31c808d8139c02?q#fe31c808d8139c02
extremely low frequency magnetic fields suppress GABA function - sci.life-extension | Google Gro
groups.google.com
This study investigated the effects of extremely low frequency magnetic fields (ELF-MFs) on the sensitivity of seizure response to bicuculline, picrotoxin and NMDA in mice. The mice were exposed to either a sham or 20 G ELF-MFs for 24 hours. Convulsants were then administered i.p. at various
http://groups.google.com/group/sci.life-extension/browse_thread/thread/607a4812640f3b20?pli=1
http://www.ncbi.nlm.nih.gov/pubmed/20381588
http://www.ncbi.nlm.nih.gov/pubmed/9096133
http://www.ncbi.nlm.nih.gov/pubmed/18602929
http://www.sciencedaily.com/releases/2010/07/100729144223.htm
Memory's master switch: Molecular power behind memory discovered
www.sciencedaily.com
A new study describes GABA, a natural molecule that occurs in the brain, which could be the main factor in regulating how many new memories we can generate. The understanding of these mechanisms might lead to the development of new memory enhancers and new treatments for neurodegenerative diseases
http://www.jneurosci.org/content/25/2/507.short Specific Modulation of Na+ Channels in Hippocampal Neurons by Protein Kinase C∊
www.jneurosci.org
Cellular/Molecular
http://www.gizmag.com/go/4635/
Electrifying food while it is being cooked could be major breakthrough
www.gizmag.com
American cookware manufacturer LifeWare Technologies has announced the launch of a new line of cookware that it claims electromechanically reduce
http://mellyoitzl.org/IRTG-school08/Speakers%20Lit/HansReul/Reul3.pdf
It may be speculated, however, that given that MSK is a potent CREB kinase and CREB phosphorylation is indeed taking place in dentate neurons after psychological stressors such as forced swimming and novelty (Bilang-Bleuel et al., 2002),
under such circumstances P-CREB may recruit one of the coactivator CREB-binding proteins (e.g. CBP, P300, pCAF) whose histone acetyl transferase (HAT) activity has been shown, at least in vitro, to acetylate histone H3 at Lys14.
http://www.xmission.com/~total/temple/Soapbox/Articles/glutathione.html
Reduced glutathione appears to be essential for maintaining normal red-cell structure and for keeping hemoglobin in the ferrous state. Magnesium deprivation resulted in elevated circulating substance P; changes in the release of other neurogenic peptides, including decreases in calcitonin generelated peptide and neuropeptide Y.
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2755791/
Caspases, a group of cysteine proteases, play an essential role in programmed cell death. Activation of caspase-3 is involved in N-arachidonoylserotonin-induced inhibition of aberrant crypt foci formation. Endocannabinoids appear to involve caspase-3 activation and subsequent apoptosis of colon preneoplastic cells.
http://www.med.upenn.edu/ins/Journal%20Club/Fall%202008/David%20Sweatt/Levenson%20and%20Sweatt%20NRN%20Epigenetics.pdf
In addition, systemic administration of the HDAC inhibitor sodium butyrate enhanced the formation of contextual fear memories98. In both studies, HDAC inhibitors did not affect short-term memory98,109. In these studies, it was possible that the drugs that were
used affected other cellular processes. However, taking all the data into consideration, these studies indicate that long-term behavioural memory regulates, and is regulated by, the epigenome.
http://en.wikipedia.org/wiki/Calpain
Calpain - Wikipedia, the free encyclopedia
en.wikipedia.org
A calpain (pronounced /ˈkælpeɪn/[1]; EC 3.4.22.52, EC 3.4.22.53) is a protein belonging to the family of calcium-dependent, non-lysosomal cysteine proteases (proteolytic enzymes) expressed ubiquitously in mammals and many other organisms. Calpains constitute the C2 family of protease clan CA in the
http://astrowow.wordpress.com/2010/12/08/apogalacticon/
http://dx.doi.org/10.1016/S0895-3988(10)60047-5
These data indicate that D-galactose and L-glucose form AGEs in vivo and that elevated AGEs may accelerate the aging process.
http://www.aseanfood.info/Articles/11022067.pdf
It is important to note that the galactose content of all fruits and vegetables analyzed was still under 40 mg/100 g, which is mimimal when compared to the galactose content of dairy products. Assuming that the galactose in dairy products is 50% of the lactose concentration, milk contains 2000–2500 mg galactose/100 g, while cheddar cheese can contain up to 1000mg/100 g.
http://www.galactose.org/research.html
http://pureformulas.com/brocco-immune-60-vcaps-by-protocol-for-life-balance.html
http://www.growery.org/forums/showflat.php/Number/526388
http://journals.cambridge.org/action/displayFulltext?type=6&fid=2688320&jid=BJN&volumeId=100&issueId=06&aid=2688316&bodyId&membershipNumber&societyETOCSession&fulltextType=RA&fileId=S0007114508975607
http://www.nutraingredients.com/Research/Orafti-consolidates-science-for-inulin-oligofructose
Rapid recovery from major depression using magnesium treatment http://www.ncbi.nlm.nih.gov/pubmed/16542786
http://pyrroloquinoline-quinone.com/
http://www.plosone.org/article/info:doi%2F10.1371%2Fjournal.pone.0006759
http://www.mall-net.com/mcs/afung.html
http://www.kefirlady.com/orderkefirgrains.htm
http://www.beneo-orafti.com/Our-Products/Natural-Food-Ingredients http://www.sabinsa.com/products/beverage-ingredients/cococin/
http://www.upo.es/export/portal/com/bin/portal/upo/profesores/amancar/profesor/1232643757415_publicaciones.pdf
http://www.upo.es/export/portal/com/bin/portal/upo/profesores/amancar/profesor/1232643757415_publica
http://www.cell.com/current-biology/abstract/S0960-9822%2808%2901614-X Current Biology - Lack of DREAM Protein Enhances Learning and Memory and Slows Brain Aging
www.cell.com
Ángela Fontán-Lozano1, Rocío Romero-Granados1, Yaiza del-Pozo-Martín1, Irene Suárez-Pereira1, José María Delgado-García1, Josef M. Penninger2, , and Ángel Manuel Carrión1, ,
Systemic administration of a histone deacetylase inhibitor, sodium butyrate (NaB; 0.3 M, 0.4 g/kg, i.p.), significantly increased the levels of LiCl-induced c-Fos and phospho-acetylated histone H3 in the CeA.
NaB(sodium butyrate) also enhanced conditioned taste aversion learning induced by pairing saccharin consumption with LiCl(lithium chloride) injection, by making the conditioned taste aversion more resistant to extinction. These results suggest that LiCl-induced c-Fos expression may be regulated by modification of histone H3, especially phospho-acetylation, in the CeA(central nucleus of the amygdala).
Chromatin modifications such as acetylation and phosphorylation are necessary for optimal gene expression, and gene expression may be increased by inhibiting the activity of histone deacetylases. LiCl (0.15 M, 12 ml/kg, i.p.) highly increased the levels of acetylation and phospho-acetylation of histone H3 in the CeA.
http://www.spacedaily.com/reports/Details_Of_Solar_Particles_Penetrating_The_Earth_Environment_Revealed_999.html
Details Of Solar Particles Penetrating The Earth Environment Revealed
www.spacedaily.com
Paris, France (ESA) Oct 04, 2006 - Co-ordinated efforts by China/ESA's Double Star and ESA's Cluster spacecraft have allowed scientists to zero in on an area where energetic particles from the Sun are blasting their way through the Earth's magnetic shield. Solar material penetrating the Earth's ma
http://www.ann-geophys.net/12/183/1994/angeo-12-183-1994.html
ANGEO - Abstract - Role of interchange instability in flux transfer event origin
www.ann-geophys.net
The instability increment is calculated for various magnitudes of the azimuthal wave number, ky, and curvature radius of the magnetic field lines, Rc. The disturbances with R-1e≤ky≤4R-1e (where Re is the Earth's radius) and Rc≅Re are the most unstable.
http://magbase.rssi.ru/REFMAN/SPPHTEXT/fte.html
Space Physics Group of Oulu
magbase.rssi.ru
One of the most interesting aspects of FTEs are their signatures on ground: they are still not known for sure (e.g., Glassmeier and Stellmacher, 1996). Number of possibilities exist:
http://en.wikipedia.org/wiki/Flux_transfer_event
Flux transfer event - Wikipedia, the free encyclopedia
en.wikipedia.org
A flux transfer event (FTE) occurs when a magnetic portal opens in the Earth's magnetosphere through which high-energy particles flow from the Sun. This connection, while previously thought to be permanent, has been found to be brief and very dynamic. The European Space Agency's four Cluster spacecr
http://www.agu.org/journals/ABS/1999/1998JA900023.shtml
http://www.ncbi.nlm.nih.gov/pubmed/18814864 Epigenetic regulation in human brain-focus on hist [Biol Psychiatry. 2009]
http://www.ncbi.nlm.nih.gov/pubmed/21421011 Posttraining systemic administration of the histon [Behav Brain Res. 2011]
http://www.fasebj.org/content/22/11/3938 Dietary uridine enhances the improvement in learning and memory produced by administering DHA to ger
www.fasebj.org
Massachusetts Institute of Technology, Department of Brain and Cognitive Sciences, Cambridge, Massachusetts, USA
http://cercor.oxfordjournals.org/content/19/suppl_1/i78.full Origin, Early Commitment, Migratory Routes, and Destination of Cannabinoid Type 1 Receptor-Containin
cercor.oxfordjournals.org
It is now well established that inhibitory interneurons of the cerebral cortex display large diversity, but where each subclass originates and how they acquire final position and physiological characteristics is only begin to be elucidated. Recent studies in
http://www.ncbi.nlm.nih.gov/pubmed/10795763 Combined oral sodium butyrate and mesalazine treat [Dig Dis Sci. 2000]
http://www.ncbi.nlm.nih.gov/pubmed/21345224 The actin-bundling protein fascin is overexpressed [BMC Gastroenterol. 2011]
http://www.nature.com/emboj/journal/v23/n6/abs/7600163a.html
http://www.nature.com/emboj/journal/v23/n6/abs/7600163a.html
Serum alpha-N-acetylgalactosaminidase (NaGalase) is responsible for the deglycosylation of vitamin D(3)-binding protein (Gc protein). The deglycosylated Gc protein cannot be converted into major macrophage-activating factor (MAF), leading to immunosuppression. NaGalase is universally detected in a variety of cancer patients, but not in healthy individuals.
http://www.isps-us.org/koehler/social_environment_influence.htm Social environment’s influence on biological processes, including gene expression
http://www.ncbi.nlm.nih.gov/pubmed/18237558 The role of reelin in adult synaptic function and [Biochim Biophys Acta. 2008]
http://people.ccmr.cornell.edu/~ginsparg/Phys446-546/fa03/nyt07oct03epi.html A Pregnant Mother's Diet May Turn the Genes Around
With the help of some fat yellow mice, scientists have discovered exactly how a mother's diet can permanently alter the functioning of genes in her offspring without changing the genes themselves.
http://en.wikipedia.org/wiki/Uridine is a molecule (known as a nucleoside) that is formed when uracil is attached to a ribose ring (also known as a ribofuranose) via a β-N1-glycosidic bond.
http://en.wikipedia.org/wiki/Calcitonin_gene-related_peptide (CGRP) is a member of the calcitonin family of peptides, which in humans exists in two forms, α-CGRP and β-CGRP. α-CGRP is a 37-amino acid peptide and is formed from the alternative splicing of the calcitonin/CGRP gene located on chromosome 11. The less-studied β-CGRP
http://digitalcommons.mcmaster.ca/dissertations/AAINR36069/ "Neuroprotection by melatonin and neural stem cells in a model of Parki" by Rohita Sharma
Several studies have reported the neuroprotective effects of administering pharmacological concentrations of the indoleamine melatonin in various models of Parkinson's disease (PD). Treatment with physiological concentrations of melatonin increased the expression of GDNF in rat C6 glioma cells.
Whereas most reelin+ Cajal–Retzius cells disappear from the brain due of programmed cell death during the early postnatal period (Super et al. 1998), CB1/reelin+ interneurons undergo a secondary migration (Morozov and Freund 2003b; Morozov et al. 2006) and appear to continue secreting reelin in a cannabinoid-dependent manner during late postnatal development and adulthood.
http://www.center4cancer.com/glyco-protein.php
Dr. Yamamoto's Vitamin-D binding protein
Vitamin-D binding protein. Dr. Nobuto Yamamoto, director of the Division of Cancer Immunology and Molecular Biology, Socrates Institute for Therapeutic Immunology, Philadelphia, Pennsylvania says this is probably the most potent macrophage activating factor ever discovered
http://www.isps-us.org/koehler/social_environment_influence.htm Social environment’s influence on biological processes, including gene expression
Needed in the art are new compounds and methods for safely and economically treating plants, with or without the above-described enhancing agents, to protect them against adverse environmental stresses and agents that can typically adversely affect the plant's own antioxidant system.
http://www.faqs.org/patents/app/20080274888#ixzz1KXgmZ5xe
N-Acetylcysteine Amide (Nac Amide) for Enhancing Plant Resistance and Tolerance to Environmental Stress
Moreover, ethanol was able to nearly abolish arachidonic acid release in response to fluoroaluminate, a direct activator of G-proteins. Altogether, the results of this study suggest that ethanol inhibits zymosan-stimulated eicosanoid production by interacting with a G-protein — or a G-protein-mediated process — that is critically involved in arachidonic acid mobilization.
Homocysteine Reduction - Homocysteine, Homocysteine Levels - Life Extension Health Concern www.lef.org
Then in 1968 a Harvard researcher named Dr. Kilmer McCully noticed that children with genetically Elevated Homocysteine Levels experienced Heart Disease similar to the Heart Disease found in middle-aged patients. Learn about Homocysteine, Homocysteine Levels, and Elevated Homocysteine Levels.
http://www.sdbonline.org/fly/neural/syntxn2b.htm Interactive Fly, Drosophila
Syntaxin 1A EVOLUTIONARY HOMOLOGS part 3/3 Vertebrate syntaxins, the Golgi apparatus, and vesicular trafficking Syntaxin 1A is a nervous system-specific protein thought to function during the late steps of the regulated secretory pathway by mediating the docking of secretory ves
Loss of p53-upregulated mediator of apoptosis (Puma) resulted in marked protection from ethanol-induced caspase-3 activation and apoptosis.
http://scholarsmine.mst.edu/post_prints/EffectsOfN-AcetylcysteineAmide%28NACA%29,AThiolAnti_09007dcc805ad00a.html
Effects of N-acetylcysteine amide (NACA), a thiol antioxidant on radiation-induced cytotoxicity in C
Ionizing radiation is known to cause tissue damage in biological systems, mainly due to its ability to produce reactive oxygen species (ROS) in cells. Many thiol antioxidants have been used previously as radioprotectors, but their application has been limited by their toxicity.
Impacts of stable element intake on 14C and 129I d [Health Phys. 2005]
http://www.mombu.com/medicine/medicine/t-zinc-l-carnosine-blocks-leaky-gut-syndrome-kidney-in-vitro-rheumatoid-arthritis-colitis-arthritis-2447626.html
http://www.nature.com/npp/journal/v36/n2/full/npp2010179a.html Neuropsychopharmacology - Regulation of Hippocampal Cannabinoid CB1 Receptor Actions by Adenosine A1
Penrose and Hameroff have suggested that microtubules function as quantum computers, with tubulin proteins within microtubules
Along similar lines, Mari Jibu, Kunio Yasue and Scott Hagan29,38 calculated that Frohlich dynamics of ordered water on microtubule surfaces, particularly the internal hollow core of microtubules, would result in quantum optical modes termed super-radiance and self-induced transparency
Conformational states of individual tubulins within neuronal microtubules are determined by quantum mechanical London forces within the tubulin interiors which can induce conformational quantum superposition. While in superposition, tubulins communicate/compute with entangled tubulins in the same microtubule, and in other microtubules in the same neuron. Quantum states in microtubules in any given neuron may extend to microtubules in neighboring neurons, and through macroscopic regions of brain via tunneling through gap junctions and possibly tunneling nanotubes. Quantum states of tubulin/microtubuless are isolated/protected from environmental decoherence by biological mechanisms which include phases of actin gelation, ordered water, plasma-like Debye layering, coherent pumping and topological quantum error correction . Microtubule quantum computations/superpositions are tuned or `orchestrated' by microtubule associated proteins during a classical, liquid phase which alternates (e.g. at 40 Hz) with a quantum, solid state phase.
Following periods of pre-conscious quantum computation (e.g. on the order of tens to hundreds of milliseconds) tubulin superpositions reduce or collapse by Penrose quantum gravity `objective reduction' (OR). The classical output states which result from the OR process are chosen non-algorithmically (`noncomputably') and then govern neurophysiological events by binding of microtubule associated proteins, regulating synapses and membrane functions etc.
The reduction or `self-collapse' in the orchestrated objective reduction `Orch OR' model is suggested to be a `conscious moment', linked to Penrose's quantum gravity mechanism which ties the process to fundamental spacetime geometry. This connection enables a pan-protopsychist approach to the `hard problem' of subjective experience
http://www.biomedsolutions.com/patents/20050143791.html
Process of Treating a Cell - US Patent Application 2005/0143791
Included in this disclosure is a process for treating a cell in which the tubulin pattern of a centriole is caused to change in response to altering its physical state. In this manner, the tubulin pattern can be selectively reprogrammed.
Quantum dipole oscillations within macroscopic proteins were first proposed by Frohlich (Proc. Natl. Acad. Sci. U.S.A. 72, 4211-4215, 1975) to regulate protein conformation and engage in macroscopic coherence. Conrad (Chaos, Solitons Fractals, v, 423-438, 1994) suggested quantum superposition of various possible protein conformations occur before one is selected. Roitberg et al (Science 268 (5315), 1319-1322, 1995) showed functional protein vibrations which depend on quantum effects centered in two hydrophobic phenylalanine residues, and Tejada et al (Science, 272, 424-426, 1996) have evidence to suggest quantum coherent states exist in the protein ferritin. In protein folding, non-local quantum electron spin interactions among hydrophobic regions guide formation of protein tertiary conformation (Klein-Seetharaman et al., Science, 295, 1719-1722, 2002), suggesting protein folding may rely on spin-mediated quantum computation. Other experiments have shown quantum wave behavior of biological porphyrin molecules (Hackermuller et al., Phys. Rev. Left. 91, 090408, 2003). In both benzene and porphyrin, and in hydrophobic aromatic amino acid groups in proteins such as tubulin, delocalizable electrons may harness thermal environmental energy to promote, rather than destroy, quantum states. For example, Ouyang and Awschalom (Science, 301, 1074-1078, 2002) showed that quantum spin transfer through biological benzene rings is more efficient at higher temperatures.
[0047] In one embodiment of this invention, the aforementioned activities which result in mirror-like centriole functions are acted upon to reset the quantum state of one centriole, reverting it to its pre-disease state. In one embodiment, the physical properties of a centriole are reset via treatment with coherent photonic radiation. This alteration of the physical properties resets the quantum state of the centriole. The entangled twin centriole then reacts to this change in quantum state and is likewise reset. By irradiating multiple cells (i.e. a tissue or an entire patient) a plurality of cells are treated. In one embodiment, the qubit patterns are reset using mediated entanglement. In another embodiment, the qubit patterns are reset using pulsed laser radiation. In one embodiment the crystallographic or otherwise obtained information demonstrating the physical state of the healthy centriole will be used to customize the laser irradiation of the diseased tissue/centrioles.
[0048] In one embodiment, the photonic radiation is coherent radiation with a narrow band wavelength of from about 400 nm to about 1060 nm. In another embodiment, the wavelength is from about 400 nm to about 800 nm. In another embodiment, the wavelength is from about 600 nm to about 750 nm. In another embodiment, the photonic radiation is non-coherent radiation with a range of wavelengths from about 400 nm to about 1060 nm. In another embodiment the photonic radiation is an interference pattern between two or more coherent laser sources.
[0049] In one embodiment coherent photonic radiation is used to inhibit mitosis in cancerous tissue by radiation with a power density between about 500 milliwatts per square centimeter and about 1 watt per square centimeter, without substantially increasing the temperature of said biological tissue but the power density is selected so as to disable or disassemble the centrioles due to the resultant optical resonant effects. This embodiment of the invention thus operates within a window of intensity; lower level photonic irradiation is known increase centriole replication, which is undesirable; higher levels result in heating of the tissue, which is likewise undesirable.
[0050] As previously discussed, within microtubules, individual tubulins exist in different states which can change on various time scales. Reference may be had to FIG. 4. In FIG. 4 the state of each centriole is euphemistically represented as either spin up or down (right or left). In actuality the states of each centriole are far more complex, since each tubulin could be in one particular binary state. There are approximately 30,000 tubulins per centriole cylinder. If each tubulin can be in one of two possible states, each centriole could be in one of 2.sup.30,000 possible states. Considering variations in isozymes and post-translational modifications, each tubulin may exist in many more than two possible states (e.g. 10), and centrioles may therefore exist in up to 10.sup.30,000 possible states. A variety of forces act upon the tubulins to generate these states, each of which corresponds with a particular state of cellular differentiation.
[0051] The types of forces operating among amino acid side groups within a protein include charged interactions such as ionic forces and hydrogen bonds, as well as interactions between dipoles--separated charges in electrically neutral groups. Dipole-dipole interactions are known as van der Waals forces and include three types: (1) permanent dipole-permanent dipole, (2) permanent dipole-induced dipole, and (3) induced dipole-induced dipole. Induced dipole-induced dipole interactions are the weakest but most purely non-polar. They are known as London dispersion forces, and although quite delicate (40 times weaker than hydrogen bonds) are numerous and highly influential. The London force attraction between any two atoms is usually less than a few kilojoules, however thousands occur in each protein. As other forces cancel out, London forces in hydrophobic pockets tend to govern protein conformational states.
[0052] London forces ensue from the fact that atoms and molecules which are electrically neutral and (in some cases) spherically symmetrical, nevertheless have instantaneous electric dipoles due to asymmetry in their electron distribution: electrons in one cloud repel those in the other, forming dipoles in each. The electric field from each fluctuating dipole couples to others in electron clouds of adjacent non-polar amino acid side groups. Due to inherent uncertainty in electron localization, the London forces which regulate tubulin states are quantum mechanical and subject to quantum uncertainty. While not wishing to be bound to any particular theory, applicants believe that 1) tubulins in microtubules and centrioles can act as qubits, and 2) centrioles, which are comprised of tubulin, are entangled through quantum entanglement and remain entangled after separation.
[0053] The enigmatic perpendicular centriole replication provides an opportunity for each tubulin in a mature ("mother") centriole to be transiently in contact, either directly or via filamentous proteins, with a counterpart in the immature ("daughter") centriole. Thus the state of each tubulin (genetic, post-translational, electronic, and conformational) may be relayed to its daughter counterpart tubulin in the replicated centriole, resulting in an identical or complementary mosaic of tubulins, and two identical or complementary centrioles. Assuming proteins may exist in quantum superposition of states, transient contact of tubulin twins during centriole replication would enable quantum entanglement so that subsequent states and activities of originally coupled tubulins within the paired centrioles would be unified. Then if a particular tubulin in one centriole cylinder is perturbed ("measured"), or its course or activities altered, its twin tubulin in the paired centriole "feels" the effect and respond accordingly in a fashion analogous to quantum entangled EPR pairs. Thus activities of replicated centrioles are mirror-like, precisely what is needed for normal mitosis. While not wishing to be bound to any particular theory, applicants believe that abnormal or absent entanglement between centrioles leads to abnormal distribution of chromosomes, aneuploidy, genomic instability and cancer.
Quantum states in proteins and protein assemblies: The essence of life? http://mitacs-gw.phys.ualberta.ca/~jtus/PDF_conferences/quantum_states.pdf
Technological quantum computation became more feasible with the advent of quantum error correction codes in the early 1990s. This means that algorithms run on the quantum computer can detect and correct errors due to random localized decoherence before they destroy the global quantum state. In some cases specific topological structural geometry of the quantum computer enhances the error correction. For example toroidal surfaces may have global, topological degrees of freedom which are protected from local errors and decoherence. The topology of microtubule lattices involves helical windings which repeat on any given protofilament according to the Fibonacci series (3,5,8,13,21…). Each of the winding patterns also corresponds with pathways along specific aromatic amino acid groups which may promote exciton or spin transfer along those pathways. If the winding patterns, rather than individual tubulin subunits are taken as qubits, then microtubules may be resistant to decoherence by virtue of topological quantum error correction. If any individual tubulin in a winding decoheres, it will resonate back into quantum superposition by other tubulins. In this scenario the output of the quantum computation will be specific combinations of winding patterns which are known to induce binding of microtubule associated proteins which in turn determine cytoskeletal structure and function.
Recent quantum information technology utilizes unpaired electron quantum spin (rather than electron location) to represent information (“spintronics”). As previously mentioned, electron quantum spin transfer through organic benzene molecules (the same as found in aromatic amino acids) is more efficient at room temperature than at absolute zero. At physiological temperature, unpaired electron spins form networks in protein interiors, and nonlocal quantum effects are important in protein folding. What about microtubules and spintronics? Microtubules are ferromagnetic lattices which align parallel to strong magnetic fields, accounted for by single unpaired electrons per tubulin. Atomic structure of tubulin shows two positively charged areas (~100-150 meV) near the alpha-beta dimer “neck” separated by a negatively charged area of about 1.5 nanometers. This region constitutes a double well potential which Figure 10. Left: A lattice neighborhood of 7 tubulin dimers showing connected locations of tryptophans and vertical pathways along protofilament; Right: Lattice neighborhood of 7 tubulin dimers with connected locations of aromatic amino acids phenylalanine and histidine which correspond with winding patterns along the 3,5 and 8 helical starts. Alternate pathways could provide topological quantum error correction via the Aharonov-Bohm effect should enable inter-well quantum tunneling of single electrons and spin states since the energy depth is significantly above thermal fluctuations (kT=25 meV at room temperature). The intra-tubulin dielectric constant is only 2, compared to roughly 80 outside the microtubule. Hence neither environmental nor thermal effects threaten quantum spin states in the double well.
Type 3 induced dipole - induced dipole interactions are the weakest but most purely non-polar. They are known as London dispersion forces, and although quite delicate (40 times weaker than hydrogen bonds) are numerous and influential. The London force attraction between any two atoms is usually less than a few kiloJoules, however thousands occur in each protein, and they may act collectively. As other forces cancel out, London forces in hydrophobic pockets can govern protein conformational states. London forces ensue from the fact that atoms and molecules which are electrically neutral and structurally symmetrical nevertheless have instantaneous electric dipoles due to asymmetry in their electron distribution. The electric field from each fluctuating dipole induces and couples to others in electron clouds of adjacent non-polar amino acid side groups. Due to inherent uncertainty in electron localization, the instantaneous London forces are quantum mechanical effects (Figure 1).
Anesthetic gases act to ablate consciousness in hydrophobic pockets of certain brain proteins.5 The anesthetic gas molecules do so by forming their own van der Waals London interactions with non-polar amino acid groups in the pockets, presumably impairing normally occurring London force effects necessary for protein functions required for consciousness.
A free radical is an atom, ion or molecule that is usually, very reactive and unstable because it has one and only one unpaired electron in an outer orbital, which explain its paramagnetic properties. Exceptions include paramagnetic transition metals like copper.
Our spin-mediated consciousness theory says that quantum spin is the seat of consciousness and the linchpin between mind and the brain, that is, spin is the mindpixel (Hu & Wu, 2002, 2004a-d).
The starting point is the fact that spin is basic quantum bit ("qubit") for encoding information and, on the other hand, neural membranes and proteins are saturated with nuclear spin carrying nuclei and form the matrices of brain electrical activities. Indeed, as discussed above, spin is embedded in the microscopic structure of spacetime as reflected by Dirac equation and is likely more fundamental than spacetime itself as implicated by Roger Penrose’s work. In the Hestenes picture the zitterbewegung associated with spin was shown to be responsible for the quantum effects of the fermion. Further, in the Bohm picture the internal motion associated with spin has been shown to be responsible for the quantum potential which, in turn, is responsible for quantum effects. Thus, if one adopts the minority quantum mind view, nuclear spins and possibly unpaired electron spins become natural candidates for mind-pixels (Hu & Wu, 2002; 2003; 2004a-d)
Applying these ideas to the particular structures and dynamics of the brain, we have theorized that human brain works as follows: Through action potential modulated nuclear spin interactions and paramagnetic O2/NO driven activations, the nuclear spins inside neural membranes and proteins form various entangled quantum states and, in turn, the collective dynamics of the said entangled quantum states produces consciousness through contextual, irreversible and non-computable means and influences the classical neural activities through spin chemistry (Hu & Wu, 2002; 2003; 2004a-d)
Urinary and cerebrospinal fluid (CSF) levels of 8-hydroxydeoxyguanosine (8-OHdG) were examined to estimate the relevance
of oxidative stress in children with brain damage. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2692890/
Immuno-spin trapping of protein and DNA radicals: “tagging” free radicals to locate and understand the redox process
http://stroke.ahajournals.org/cgi/content/full/strokeaha;28/10/2018 Superior Neuroprotective Efficacy of a Novel Antioxidant (U-101033E) With Improved Blood-Brain Barrier Permeability in Focal Cerebral Ischemia
http://www.subtleenergies.com/ormus/tw/spincoherence.htm
Glycerol oxidation in discrete areas of rat brain from young, adolescent, and adult rats
We have reported previously that the oxidation rate of [1,3-14C] glycerol to 14CO2 is lower in whole brain homogenates from neonatal rats and increases about 30% during the suckling period to adult levels
Oxidation of ethanol in the brain and its consequences
Acetaldehyde, a toxic byproduct of ethanol metabolism, may be at least partially responsible for ethanol's actions in the CNS (Hunt 1996; Hashimoto et al. 1989; Bergamaschi et al. 1988; Zimatkin and Deitrich 1997; Thadani and Truitt 1977; Collins et al. 1988; Heap et al. 1995)
Reversal of age-related increase in brain protein oxidation, decrease in enzyme activity, and loss in temporal and spatial memor
Oxygen free radicals and oxidative events have been implicated as playing a role in bringing about the changes in cellular function that occur during aging
Brain oxidation is an initial process in sleep induction
CNS activity is generally coupled to the vigilance state, being primarily active during wakefulness and primarily inactive during deep sleep
Metabolic, immune, epigenetic, endocrine and phenotypic abnormalities found in individuals with autism spectrum disorders, Down syndrome and Alzheimer disease may be caused by congenital and/or acquired chronic cerebral toxoplasmosis
http://dx.doi.org/10.1016/j.rasd.2010.03.009
Local interactions between anandamide, an endocannabinoid, and ibuprofen, a nonsteroidal anti-inflammatory drug, in acute and inflammatory pain.
Because bradyzoites and sporozoites throughout their life cycle accumulate large amounts of crystalline storage polysaccharide granules analogous to amylopectin within the cytoplasm and are able to build more complex macromolecules, they may be at least in part responsible for the production of amyloid-β senile plaques. Moreover, it seems that the accumulation of iron in senile plaques reflect a defense of the host against T. gondii because this transition metallic ion is necessary for proliferation of tachyzoites. Finally, the beneficial effects of ibuprofen in the patients with AD that restored cellular immunity, decreased production of proinflammatory cytokines, NO, amyloid-β, reduced lipid peroxidation and free radical generation, were consistent with the suggestion that congenital and/or acquired chronic latent CT play an important role in development of these types of neurodegeneration
The three pathways for the metabolism of acetaminophen are glucuronidation, sulfation, and the cytochrome P-450 system. One study of children with autism indicated that these children had a sulfation deficit which causes them to process acetaminophen differently from control children (Alberti et al. 1999).
Sulfation is the primary pathway for acetaminophen metabolism until age 10–12 years (Defendi and Tucker 2009). It is possible that children predisposed to developing autism have a sulfation deficit which may lead to increased blood levels of acetaminophen after therapeutic doses of acetaminophen are administered
Monocytes are one of the primary cells of the immune system and differentiate into macrophages and dendritic cells. If the evidence is correct that acetaminophen acts as an activator of cannabinoid receptors, then activating CB2 receptors could influence the growth of monocytes. Data from our lab indicates that acetaminophen in the media inhibits the cell division of monocytes in a dose dependent manner as assayed with resazurin stain for mitochondrial dehydrogenase activity. Inhibition of growth is noted even at the therapeutic concentration of 20 micrograms per milliliter. If as proposed, children with autism are poor metabolizers of acetaminophen, higher than normal therapeutic levels could be possible with recommended doses which could lead to a greater inhibition of monocytes
It has been shown in several studies that children with autism have immune system dysregulation (Warren et al. 1996, Jyonouchi et al. 2005, Ashwood et al. 2006, Molloy et al. 2006, Li et al. 2009, Entstrom et al. 2010). This dysregulation includes differential monocyte responses, abnormal T helper cytokine levels, decreased T cell mitogen response, decreased numbers of lymphocytes, and abnormal serum immunoglobulin levels. Many studies have shown that children with autism exhibit autoimmunity, in particular antibodies against brain and central nervous system proteins (Singh et al. 1993, Connolly et al. 1999, Ashwood and Van De Water 2004, Cohly and Panja 2005, Kawashti et al. 2006, Wills et al. 2007, Martin et al. 2008). It is proposed that the immune dysregulation in children with autism is due to the influence of acetaminophen on CB2 receptors during gestation or in early childhood
It has been proposed that the blockage of fever with antipyretics (as acetaminophen) could lead to autism by interfering with normal immunologic development (Torres 2003). Children with autism have reported to have a decrease in autism symptoms when they have a fever (Sullivan 1980, Cotterill 1985, Torres 2003, Curran et al. 2007). It is interesting to note that activation of CB1 receptors, in addition to providing an analgesic effect, causes a decrease in body temperature
(Fraga et al. 2009). This type of effect may be further evidence of endocannabinoid disruption in children with autism
Other environmental factors may also be involved in triggering autism. For example, low levels of breastfeeding could decrease immune protection in infants by decreasing mother to child transfer of IgA. Decreased immune protection could make a child more vulnerable to viral infection which in theory could lead to autism. Lack of breastfeeding has been shown to be associated with autism (Schultz et al. 2006). This same study found an association between use of infant formula without docosahexaenoic acid or arachidonic acid supplementation and autism. Arachidonic acid metabolism is an integral part of the endocannabinoidsystem and its disruption could be further evidence of a role for the endocannabinoid system in autism
http://en.wikipedia.org/wiki/Hysteresis is essential to the workings of the memristor, a circuit component which "remembers" changes in the current passing through it by changing its resistance.
'Missing link' memristor created: Rewrite the textbooks? www.eetimes.com
HP Labs' Stanley Williams has invented the world's first memristor, the 'missing link' in circuit theory--a fourth passive-device type after resistors, capacitors and inductors--as predicted by University of California at Berkeley professor, Leon Chua.
http://dx.doi.org/10.1016/j.ejphar.2007.05.062
http://dx.doi.org/10.1016/j.pnpbp.2008.11.010
http://dx.doi.org/10.1016/j.jneuroim.2006.05.004 Acute restraint stress in rats was found to induce an increase in glutathione levels in the cerebellum after 2 and 4 h of immobilization
Repeated restraint stress suppresses neurogenesis and induces biphasic PSA-NCAM expression in the adult rat dentate gyrus.
The results show that acute restraint stress did not change either the proliferation of dentate gyrus precursor cells or the expression of polysialylated neural cell adhesion molecule, whereas 3 weeks of chronic restraint stress suppressed proliferation by 24% and increased polysialylated neural cell adhesion molecule expression by 40%. The study was extended for an additional 3 weeks to trace the survival and development of the cells born after the initial 3 weeks of restraint. Rats subjected to 6 weeks of daily restraint stress exhibited suppressed cell proliferation and attenuated survival of the recently born cells after the extended time course, resulting in a 47% reduction of granule cell neurogenesis. Furthermore, 6 weeks of chronic stress significantly reduced the total number of granule cells by 13% and the granule cell layer volume by 5%. Expression of polysialylated neural cell adhesion molecule followed a biphasic time course, displaying a significant up-regulation after 3 weeks of daily restraint stress that was lost after 6 weeks of stress. These studies may help us understand the basis for hippocampal shrinkage and raise questions about the ultimate reversibility of the effects of chronic stress
Chronic restraint stress decreases the expression of glutathione S-transferase pi2 in the mouse hippocampus
Chronic restraint stress in mice affects hippocampal structure and function. Mice were subjected to daily restraint for 3 weeks, and gene expression in hippocampus was compared to controls using large-scale cDNA microarrays. We found that 444 genes were differentially expressed, and further analysis of 6 genes by real-time reverse transcription PCR confirmed that 3 of them were downregulated by stress. These 3 genes, growth factor receptor-bound protein 2 (Grb2), phosphatidylinositol-4-phosphate 5-kinase, type 1 beta (Pip5k1b), and glutathione S-transferase, pi2 (Gstp2), were also analyzed by in situ hybridization. The downregulation of Gstp2 may induce an increase of oxidative damage in the pyramidal cells of the CA1 and CA3 regions and granular layer of the dentate gyrus, leading to structural and functional damage. Those regions are affected by stress, and our results could help understand further the mechanisms involved in the occurrence of stress-related disorders
http://lib.bioinfo.pl/pmid:15576840
http://lib.bioinfo.pl/pmid:15525997
http://lib.bioinfo.pl/pmid:15331569
http://lib.bioinfo.pl/pmid:15787710
http://lib.bioinfo.pl/pmid:19675536
http://lib.bioinfo.pl/pmid:19563475
http://lib.bioinfo.pl/pmid:19259645
http://lib.bioinfo.pl/pmid:12839875
http://lib.bioinfo.pl/pmid:19357347
http://lib.bioinfo.pl/pmid:18509042
http://lib.bioinfo.pl/pmid:17409233
The postmortal accumulation of brain N-arachidonylethanolamine (anandamide) is dependent upon fatty acid amide hydrolase activity. The endocannabinoid system and multiple sclerosis. Role of cannabinoids and endocannabinoids in cerebral ischemia. The endocannabinoid system: a n
http://lib.bioinfo.pl/pmid:20133390
http://lib.bioinfo.pl/pmid:19484221
http://lib.bioinfo.pl/pmid:20405543
http://lib.bioinfo.pl/pmid:19154758
http://lib.bioinfo.pl/pmid:16950524
Propionic acid, a widely used food preservative, derived from the bacteria that makes the holes in swiss cheese, shown to cause neuroinflammation and worsen or induce symptoms of autistic spectrum disorder.
http://lib.bioinfo.pl/pmid:18395759
Intracerebroventricular injection of propionic acid, an enteric bacterial metabolic end-product, impairs social behavior in the rat: Implications for an animal model of autism.
Compared to controls, rats treated with PPA displayed social behavior impairments as indicated by significantly greater mean distance apart, reduced time spent in close proximity, reduced playful interaction, and altered responses to playful initiations. Treatment with another short chain fatty acid, sodium acetate, produced similar impairments.
http://en.wikipedia.org/wiki/Propionibacteria Propionic acid (PPA) is a short chain fatty acid and an important intermediate of cellular metabolism. PPA is also a by-product of a subpopulation of human gut enterobacteria and is a common food preservative. We examined the behavioural, electrophysiological, neuropathological, and biochemical effects of treatment with PPA and related compounds in adult rats. Intraventricular infusions of PPA produced reversible repetitive dystonic behaviours, hyperactivity, turning behaviour, retropulsion, caudate spiking, and the progressive development of limbic kindled seizures, suggesting that this compound has central effects. Biochemical analyses of brain homogenates from PPA treated rats showed an increase in oxidative stress markers (e.g., lipid peroxidation and protein carbonylation) and glutathione S-transferase activity coupled with a decrease in glutathione and glutathione peroxidase activity. Neurohistological examinations of hippocampus and adjacent white matter (external capsule) of PPA treated rats revealed increased reactive astrogliosis (GFAP immunoreactivity) and activated microglia (CD68 immunoreactivity) suggestive of a neuroinflammatory process. This was coupled with a lack of cytotoxicity (cell counts, cleaved caspase 3′ immunoreactivity), and an increase in phosphorylated CREB immunoreactivity. We propose that some types of autism may be partial forms of genetically inherited or acquired disorders involving altered PPA metabolism. Thus, intraventricular administration of PPA in rats may provide a means to model some aspects of human ASD in rats
Sodium acetate may be added to foods as a seasoning. It may be used in the form of sodium diacetate — a 1:1 complex of sodium acetate and acetic acid,[1] given the E-number E262. A frequent use of this form is in salt and vinegar chips in the United States. Many US brands, including national manufacturer Frito-Lay, sell "salt and vinegar flavoured" chips that use this chemical, with lactose and smaller percentages of other chemicals, in lieu of a real salt and vinegar preparation.
Stephen Hecht and colleagues at the University of Minnesota in Minneapolis asked 12 volunteers with a history of smoking to smoke a cigarette laced with phenanthrene, a type of PAH that binds with DNA but is non-carcinogenic.
The results demonstrated that the three-step pathway resulting in the formation of diol epoxides, as monitored by [D10]PheT, occurred with remarkable rapidity. Levels of [D10]PheT in plasma of all subjects were maximal at the earliest time points examined, 15−30 min after smoking the cigarette containing [D10]phenanthrene, and decreased thereafter. These results demonstrate that the formation of a polycyclic aromatic hydrocarbon diol epoxide occurs rapidly in smokers. Because polycyclic aromatic hydrocarbon diol epoxides are mutagenic and carcinogenic, the results clearly demonstrate immediate negative health consequences of smoking
Omega-3 supplementation by pregnant mothers restores deficits in prepulse inhibition (PPI), a behavioral response that is impaired during a window of 3-5 weeks during nursing, by restoring hippocampal neurogenesis in children that would later develop schizophrenia, autism, and bipolar disorder.
Arachidonic Acid Drives Postnatal Neurogenesis and Elicits a Beneficial Effect on Prepulse Inhibitio
It is noteworthy that the administration of ARA successfully and dramatically increased neurogenesis not only in wild-type but also Pax6(+/−) rats. It is known that prostaglandin E2 (PGE2) plays an important role in neurogenesis [26], stimulates CB2, a receptor for endocannabinoids and promotes mouse neural stem cell proliferation [27]. Both PGE2 and endocannabinoids are metabolites of ARA. It is also possible that ARA itself augments proliferation of neural progenitor cells. ARA could be transmitted from Fabps to nuclear receptor proteins [17], thereby indirectly controlling the transcription of genes related to cell proliferation. This scenario is analogous to that where retinoic acid (a metabolite of vitamin A) is transmitted from a cellular retinoic acid binding protein and Fabp5 to nuclear receptors RAR and PPARβ/δ, respectively [28]. We also speculate from our current study that the effect of DHA albeit small, may be caused by promoting differentiation and prevention of apoptosis, rather than by increasing cell proliferation
As a test of plausibility for the hypothesis that schizophrenia can result from abnormal brain, especially cerebral cortical, development, these studies examined whether, in the rat, disruption of brain development initiated on embryonic day (E) 17, using the methylating agent methylazoxymethanol acetate (MAM), leads to a schizophrenia-relevant pattern of neural and behavioral pathology. Specifically, we tested whether this manipulation leads to disruptions of frontal and limbic corticostriatal circuit function, while producing schizophrenia-like, region-dependent reductions in gray matter in cortex and thalamus. METHODS: In offspring of rats administered MAM (22 mg/kg) on E17 or earlier (E15), regional size, neuron number and neuron density were determined in multiple brain regions. Spontaneous synaptic activity at prefrontal cortical (PFC) and ventral striatal (vSTR) neurons was recorded in vivio. Finally, cognitive and sensorimotor processes mediated by frontal and limbic corticostriatal circuits were assessed. RESULTS: Adult MAM-E17-exposed offspring showed selective histopathology: size reductions in mediodorsal thalamus, hippocampus, and parahippocampal, prefrontal, and occipital cortices, but not in sensory midbrain, cerebellum, or sensorimotor cortex. The prefrontal, perirhinal, and occipital cortices showed increased neuron density with no neuron loss. The histopathology was accompanied by a disruption of synaptically-driven "bistable membrane states" in PFC and vSTR neurons, and, at the behavioral level, cognitive inflexibility, orofacial dyskinesias, sensorimotor gating deficits and a post-pubertal-emerging hyper-responsiveness to amphetamine. Earlier embryonic MAM exposure led to microcephaly and a motor phenotype. CONCLUSIONS: The "MAM-E17" rodent models key aspects of neuropathology in circuits that are highly relevant to schizophrenia
Isothiocyanates are derived from the hydrolysis (breakdown) of glucosinolates sulfur-containing compounds found in cruciferous vegetables. They are shown to increase longevity! Buy some garden cress seeds! Lepidium sativum is the name, and it's high in Omega-3s, and glucosinolates.
Garden cress ½ cup (25 g) 98mg Glucotropaeolin
http://lpi.oregonstate.edu/infocenter/phytochemicals/isothio/
Bio-availability and metabolism of n-3 fatty acid rich garden cress (Lepidium sativum) seed oil in albino rats
The Effects of Lepidium sativum Seeds on Fracture-Induced Healing in Rabbits
http://www.ncbi.nlm.nih.gov/sites/ppmc/articles/PMC1994840/ A Study on Clinical Efficacy of Lepidium sativum Seeds in Treatment of Bronchial Asthma
http://ijpt.iums.ac.ir/index.php/ijpt/article/viewFile/060501055/212 Physicochemical Properties of Garden Cress (Lepidium sativum L.) Seed Oil
http://findarticles.com/p/articles/mi_hb5762/is_201005/ai_n53933020/
Garden cress (GC) is an annual, glabrous, erect herb cultivated as a culinary vegetable all over Asia and Europe [1, 2]. It is commonly cultivated throughout the temperate regions of India and Pakistan [I]. The GC plant is cultivated in Ethiopia for the edible oil from its seeds [3]. Egyptians used GCO mixed with wild mustard seed oil to stabilise unstable linseed oil [4]. Medieval Indian medical texts record the medicinal properties of the GC plant [1, 2]. Since ancient times, the seeds have been used in local traditional medicine [5]. The GC seeds are bitter, thermogenic, depurative, rubefacient, galactogogue, tonic, aphrodisiac, ophthalmic, antiscorbutic, antihistaminic and diuretic. They are useful in the treatment of asthma, coughs with expectoration, poultices for sprains, leprosy, skin disease, dysentery, diarrhoea, splenomegaly, dyspepsia, lumbago, leucorrhoea, scurvy and seminal weakness [2]. The seedlings are consumed as a spice and are a rich source of glucosinolates [6]. Seeds, leaves and roots of GC are of economic importance too. In India, GC is mainly cultivated for its seeds. Fresh leaves are mainly used in salad and have antibacterial, diuretic and stimulant properties. The juice of eight-day-old, whole GC plants has been shown to be chemoprotective against IQ (2-amino-3-methylimidazo [4.5-/]quinoline)-induced genotoxic effects and colonic neoplastic lesions in rats [7]. GC seeds have been shown to reduce the symptoms of asthma and improve lung function in asthmatics [8]. The seeds have been reported as possessing a hypoglycemic property [9]
The study, of the total glucosinolates of the seeds of Lepidium sativum revealed the presence of two glucosinolates, glucotropaeolin and gluconasturin. On the other hand, four glucosinolates were isolated from the fresh herb and were identified as 2 – ethyl butyl glucosinolate, methyl glucosinolate (glucocapparin), butyl glucosinolate in addition to the glucotropaeolin which was isolated also from the seeds.
Nanomolecular Gravitational Interactions Causing Increased Probability of Birth Defects in Humans During Period from Conception to Early Fetus Formation
Induced change in centriole separation and consequent probability for disadvantageous mutation
http://www.nsti.org/publications/MSM/2002/pdf/144.pdf
http://www.nsti.org/publications/MSM/2002/pdf/144.pdf
It is found that small decreases in gravity that are caused by planet syzygy, full moon presence,and cosmogonic events of deep space can cause a sufficient change in gravitational interactions to affect the nucleons of a single cell or a small nanocluster of cells after initial mitosis such that small but significant changes in normal centriole separation can occur. These slight modifications can cause modifications in bond lengths and bond angles of sheathing water molecules, and changes of the helical DNA structure, and lead to a mutation with adverse consequences
Official 2012 Countdown widgetserver.com The official countdown to the end of the Mayan calendar 2012 www.Official2012Countdown.com On December 21st, 2012 A.D. the ancient Mayan Long Count Calendar comes to an abrupt end. There are many scientific theories and historic prophecies
3. Paroxetine (Paxil) - An SSRI antidepressant drug that is 10.3 times more likely to be associated with violence than other drugs. It is also linked to severe withdrawal symptoms and birth defects.
2. Fluoxetine (Prozac) - A popular SSRI antidepressant drug that is 10.9 times more likely to be associated with violence than other drugs.
www.naturalnews.com
Study reveals top ten violence-inducing prescription drugs
http://www.sciencedaily.com/releases/2011/01/110114081653.htm
http://ehp03.niehs.nih.gov/article/info%3Adoi%2F10.1289%2Fehp.1002727
99% of pregnant women in US test positive for multiple chemicals including banned ones, study sugges
The bodies of virtually all US pregnant women carry multiple chemicals, including some banned since the 1970s and others used in common products such as non-stick cookware, processed foods and personal care products, according to a new study.
The side effect of prolonged laptop use on bare legs (or 'toasted skin syndrome') as temperature und
www.indopost.com
A team of researchers of the University Hospital Basel from Swiss has published a report via medical journal Pediatrics and found that computer laptop users who resting their laptops on bare legs for a few hours a day for several
Infinity Announces That Purdue Pharmaceutical Products L.P. and Mundipharma International Corporation financial.businessinsider.com
Chronic stress and impaired glutamate function elicit a depressive-like phenotype and common changes in gene expression in the mouse frontal cortex
http://www.europeanneuropsychopharmacology.com/article/S0924-977X(10)00143-4/abstract
http://www.europeanneuropsychopharmacology.com/article/S0924-977X(10)00143-4/abstract
Major depression might originate from both environmental and genetic risk factors. The environmental chronic mild stress (CMS) model mimics some environmental factors contributing to human depression and induces anhedonia and helplessness. Mice heterozygous for the synaptic vesicle protein (SVP) vesicular glutamate transporter 1 (VGLUT1) have been proposed as a genetic model of deficient glutamate function linked to depressive-like behaviour. Here, we aimed to identify, in these two experimental models, gene expression changes in the frontal cortex, common to stress and impaired glutamate function.
Both VGLUT1+/− and CMS mice showed helpless and anhedonic-like behavior. Microarray studies in VGLUT1+/− mice revealed regulation of genes involved in apoptosis, neurogenesis, synaptic transmission, protein metabolic process or learning and memory. In addition, RT-PCR studies confirmed gene expression changes in several glutamate, GABA, dopamine and serotonin neurotransmitter receptors. On the other hand, CMS affected the regulation of 147 transcripts, some of them involved in response to stress and oxidoreductase activity. Interestingly, 52 genes were similarly regulated in both models. Specifically, a dowregulation in genes that promote cell proliferation (Anapc7), cell growth (CsnK1g1), cell survival (Hdac3), and inhibition of apoptosis (Dido1) was observed. Genes linked to cytoskeleton (Hspg2, Invs), psychiatric disorders (Grin1, MapK12) or an antioxidant enzyme (Gpx2) were also downregulated. Moreover, genes that inhibit the MAPK pathways (Dusp14), stimulate oxidative metabolism (Eif4a2) and enhance glutamate transmission (Rab8b) were upregulated.
Consciousness is getting closer to anatomical elucidation.
We have recently found that, in layer V of rat neocortex, a subtype of GABAergic interneurons, classified as low-threshold spiking (LTS), undergoes a prominent and long-lasting hyperpolarization following their own repetitive firing. This slow self-inhibition (SSI) is due to the postsynaptic activation of a G-protein-coupled inward rectifier potassium (GIRK) conductance triggered by an activity-dependent autocrine action of endocannabinoids. Slow self-inhibition (SSI) of LTS cortical interneurons is an endocannabinoid-dependent persistent and prominent change of somatodendritic excitability. In the neocortex and hippocampus, interneurons are important players in cortical circuit activity. Some interneurons such as basket cells are responsible for induction and maintenance of various cortical oscillations, by providing feedback inhibition onto glutamatergic pyramidal cells. In contrast, other GABAergic interneurons target pyramidal cell dendrites and might be thus responsible for filtering excitation onto pyramidal neurons.
Neocortical LTS interneurons belong to this latter class of cells and their self-induced inhibition by 2-AG might provide a persistent tuning of information processing along the dendritic axis of pyramidal cells.
The neocortex is divided into frontal, parietal, occipital, and temporal lobes, which perform different functions. For example, the occipital lobe contains the primary visual cortex, and the temporal lobe contains the primary auditory cortex.
http://www.nextbio.com/b/search/lit/URB597?type=treatment#sortBy=date
http://www.pjoes.com/pdf/12.2/163-169.pdf
http://onlinelibrary.wiley.com/doi/10.1111/j.1476-5381.2010.00716.x/abstract
http://www.mdpi.com/2072-6651/2/4/593/pdf
http://molpharm.aspetjournals.org/content/78/2/260.abstract
http://onlinelibrary.wiley.com/doi/10.1111/j.1369-1600.2010.00222.x/abstract
http://www.pjoes.com/pdf/12.2/163-169.pdf
http://www.jpp.krakow.pl/journal/archive/09_09/pdf/119_09_09_article.pdf
http://www.dissertations.se/dissertation/7c51bcf947/
http://umu.diva-portal.org/smash/get/diva2:213724/FULLTEXT01
http://www.nejm.org/doi/pdf/10.1056/NEJM198805263182102
Autism is a neurologic disorder that severely impairs social, language, and cognitive development. Whether autism involves maldevelopment of neuroanatomical structures is not known.
The size of the cerebellar vermis in patients with autism was measured on magnetic resonance scans and compared with its size in controls. The neocerebellar vermal lobules VI and VII were found to be significantly smaller in the patients. This appeared to be a result of developmental hypoplasia rather than shrinkage or deterioration after full development had been achieved. In contrast, the adjacent vermal lobules I to V, which are ontogenetically, developmentally, and anatomically distinct from lobules VI and VII, were found to be of normal size. Maldevelopment of the vermal neocerebellum had occurred in both retarded and nonretarded patients with autism. This localized maldevelopment may serve as a temporal marker to identify the events that damage the brain in autism, as well as other neural structures that may be concomitantly damaged.
Our findings suggest that in patients with autism, neocerebellar abnormality may directly impair cognitive functions that some investigators have attributed to the neocerebellum; may indirectly affect, through its connections to the brain stem, hypothalamus, and thalamus, the development and functioning of one or more systems involved in cognitive, sensory, autonomic, and motor activities; or may occur concomitantly with damage to other neural sites whose dysfunction directly underlies the cognitive deficits in autism.
http://dx.doi.org/10.1016/j.pscychresns.2009.12.004
Abnormal cerebellar morphometry in abstinent adolescent marijuana users
Functional neuroimaging data from adults have, in general, revealed frontocerebellar dysfunction associated with acute and chronic marijuana (MJ) use. The goal of this study was to characterize cerebellar volume in adolescent chronic MJ users following 1 month of monitored abstinence. Participants were MJ users (n = 16) and controls (n = 16) aged 16–18 years. Extensive exclusionary criteria included history of psychiatric or neurologic disorders. Drug use history, neuropsychological data, and structural brain scans were collected after 28 days of monitored abstinence. Trained research staff defined cerebellar volumes (including three cerebellar vermis lobes and both cerebellar hemispheres) on high-resolution T1-weighted magnetic resonance images. Adolescent MJ users demonstrated significantly larger inferior posterior (lobules VIII–X) vermis volume than controls, above and beyond effects of lifetime alcohol and other drug use, gender, and intracranial volume. Larger vermis volumes were associated with poorer executive functioning. Following 1 month of abstinence, adolescent MJ users had significantly larger posterior cerebellar vermis volumes than non-using controls. These greater volumes are suggested to be pathological based on linkage to poorer executive functioning. Longitudinal studies are needed to examine typical cerebellar development during adolescence and the influence of marijuana use.
http://www.nature.com/npp/journal/v21/n1/full/1395350a.html
Since qualitative CT studies have suggested decreased cerebellar size in patients with bipolar disorder, we performed a quantitative analysis of the cerebellum in patients with bipolar disorder
The number of previous episodes of depression may be largely associated with the smaller V3 area in multiple-episode patients, but this requires future study. Others (Shah et al. 1992) found that depressed patients have smaller anterior, posterior and total vermal areas compared to healthy volunteers.
Vermal area 3 (lobules VIII-X) consists of the inferior posterior lobe and nodulus (flocculonodular lobe) of the vermis. Several animal studies support the possibility that these regions play a role in the modulation of behavior. Anand et al. (1959) stimulated the flocculonodular lobe and the anterior and posterior portions of the vermis of dogs and found heavy projections from the flocculonodular and adjoining posterior regions of the vermis to the orbitomesial cortex, anterior cigulate gyrus, amygdala, hippocampal and dentate gyri, pyriform and periamygdaloid cortical regions, and hypothalamus, all of which are believed to regulate mood
Higher IQ subjects have not only a higher memory span, but consequently also more complex waveforms of EEG than lower IQ subjects. The most extreme compression of information is represented by the eigenvalues of the power spectrum. There are as much eigenvalues of a spectrum as are harmonics.
http://www.v-weiss.de/spinadel.html
http://www.v-weiss.de/spinadel.htmlare
It is a psychoacoustic fact, known as octave equivalence (GLASSMAN 1999) that all known musical cultures consider a tone twice the frequency of another to be, in some sense, the same tone as the other (only higher). The point of resonance, corresponding to the eigenvalues and zero-crossings of a wave packet (wavelet), is not the frequency of its fundamental, but half of its frequency.
Temporal Interactions between Cortical Rhythms
When a small area of cortex is stimulated a gamma frequency rhythm is generated riding on a post-stimulus depolarisation of both principal cells and local circuit interneurons (Traub et al., 1996). The basic feature of this form of gamma rhythm is the locally synchronous activity generated by interneuron networks, with resulting inhibitory postsynaptic potentials (IPSPs) governing the times at which principal cells may generate action potentials. These principal cell action potentials feed back to local interneurons to generate and modify interneuronal spiking. However, when stimulation is more intense, or more than one region is co-activated, this gamma rhythm transforms into a beta frequency oscillation, with this frequency being approximately half that of the original gamma rhythm.
http://www.v-weiss.de/spinadel.html
The pattern of neuronal connectivity within a single cortical column is extremely rich (Binzegger et al., 2004; Thomson et al., 2002), making it likely that even local networks in completely different laminae may readily interact. A solution to the interference problem can be found if the ratio of frequencies is ‘irrational’ . In this situation the two rhythms never fully synchronise and the phase relationship between frequencies constantly changes. Coexistent gamma and beta2 rhythms in association cortex provide an example of this method from minimising interference. The two rhythms are generated in different cortical laminae and survive physical separation of these laminae (Roopun et al., 2006). The ratio of modal peak frequencies is approximately phi, resulting in a periodic pattern of change in low-level synchrony between laminae with period equal to the sum of the two periods of oscillation present. This phenomenon can occur, to some extent, with any pair of co-expressed frequencies. However, in using phi as a common ratio between adjacent frequencies in the EEG spectrum, the neocortex appears to have found a way to pack as many, minimally interfering frequency bands as possible into the available frequency space.
If the cortex uses different frequency bands to process different aspects of incoming information then it must also possess the ability to combine information held in these bands to reconstruct this input. Patterns of sensory information are capable of subtle modification of peak frequencies associated with processing input (Gieselmann and Thiele, 2008) such that the background framework of minimally interfering multiple frequencies (above) is disrupted. In such a situation it is possible that frequency ratios may become more favourable for direct temporal interaction between bands. Evidence for this is available from studies using measures of phase synchrony between frequencies. When frequency ratios are integer values, strong phase synchrony can be seen in human MEG recordings (Palva et al., 2005). The key feature of this relationship is that phase between two frequencies must be non-randomly ordered. Stable (i.e. non-random) phase relationships are seen between frequencies with ratios of 2, 3 and 4 during mental arithmetic tasks in topographically localised regions of neocortex, and the phenomenon has been proposed to be involved in memory matching and attention (Sauseng et al., 2008).
Perhaps the most readily observable form of cross-frequency interaction is that of ‘nesting’. Here the amplitude (power) of a discrete frequency band is modified according to the phase of a lower frequency, coexistent rhythm. This pattern is seen when considering gamma rhythms coexisting with theta frequency oscillations in hippocampus (Bragin et al., 1995). Hierarchies of nested rhythms are also seen. Nesting of delta, theta and gamma rhythms exists both in hippocampus (Penttonen and Buzsaki, 2003) and neocortex (Lakatos et al., 2005). This arrangement of rhythms ensures successively higher frequencies are maximally expressed in a manner dependent on the lower frequencies in the hierarchy and does not, per se, imply precise phase relationships. However, when nesting is seen it is possible to discern stable phase relationships between different frequencies in a manner, at least superficially, similar to phase synchrony (Lakatos et al., 2005).
The generation of the Nambu-Goldstone mode in brain corresponds to a memory-storage while an excitation of the NG mode is a recalling of the memory. Therefore, based on our discussion given above, we regard brain is a kind of spin system and the NG boson of brain is interpreted as a magnon. Here we would like to make an argument that the dynamics in brain should be described by the theory of magnetism
http://arxiv.org/PS_cache/quant-ph/pdf/0306/0306021v1.pdf
After we obtain this viewpoint, we can employ various powerful methods in condensed matter physics to study brain. When the spin system is under a broken-symmetry phase, the system stores a memory, and the excitation of a magnon mode is the recalling of the memory. For example, the thermodynamics of brain can also be studied by the method of the spin system. The effect of the thermal noise can be incorpolated into the theory of brain. The Neel temperature or Curie temperature are interpreted as the temperatures of brain at which the disappearances of the memories might be happend. It is interesting for us to examine what character brain has; ferromagnetic, antiferromagnetic or other types of order. It is well-known fact that the dispersion relation of the magnon is different between in the ferromagnetic and antiferromagnetic cases.
The Model of the Theory of the Quantum Brain Dynamics can be cast on the Heisenberg Spin Hamiltonian http://arxiv.org/PS_cache/quant-ph/pdf/0306/0306021v1.pdf
http://www.v-weiss.de/chaos.html
Reading rate, short term memory, IQ and clock cycle of brain waves
www.v-weiss.de
Empirical data for breaking the code of the brain, the power of the mind, golden mean shift, the golden mean as the fundamental of brain waves
http://www.ncbi.nlm.nih.gov/pubmed/19887554Synthetic cannabinoid receptor agonists inhibit tu [Mol Cancer Ther. 2009]
Cannabinoids have been reported to possess antitumorogenic activity. Not much is known, however, about the effects and mechanism of action of synthetic nonpsychotic cannabinoids on breast cancer growth and metastasis. We have shown that the cannabinoid receptors CB1 and CB2 are overexpressed in primary human breast tumors compared with normal breast tissue. We have also observed that the breast cancer cell lines MDA-MB231, MDA-MB231-luc, and MDA-MB468 express CB1 and CB2 receptors. Furthermore, we have shown that the CB2 synthetic agonist JWH-133 and the CB1 and CB2 agonist WIN-55,212-2 inhibit cell proliferation and migration under in vitro conditions. These results were confirmed in vivo in various mouse model systems. Mice treated with JWH-133 or WIN-55,212-2 showed a 40% to 50% reduction in tumor growth and a 65% to 80% reduction in lung metastasis. These effects were reversed by CB1 and CB2 antagonists AM 251 and SR144528, respectively, suggesting involvement of CB1 and CB2 receptors. In addition, the CB2 agonist JWH-133 was shown to delay and reduce mammary gland tumors in the polyoma middle T oncoprotein (PyMT) transgenic mouse model system. Upon further elucidation, we observed that JWH-133 and WIN-55,212-2 mediate the breast tumor-suppressive effects via a coordinated regulation of cyclooxygenase-2/prostaglandin E2 signaling pathways and induction of apoptosis. These results indicate that CB1 and CB2 receptors could be used to develop novel therapeutic strategies against breast cancer growth and metastasis.
Beneficial effects of cannabinoids (CB) in a murine model of allergen-induced airway inflammation: Role of CB(1)/CB(2) receptors
http://www.ncbi.nlm.nih.gov/pubmed/21056512
The endocannabinoid system (ECS) consists of two cannabinoid (CB) receptors, namely CB(1) and CB(2) receptor, and their endogenous (endocannabinoids) and exogenous (cannabinoids, e.g. delta-9-tetrahydrocannabinol (THC)) ligands which bind to these
Beneficial effects of cannabinoids (CB) in a murin [Immunobiology. 2010]
THC treatment of C57BL/6 wildtype mice dramatically reduced airway inflammation as determined by significantly reduced total cell counts in bronchoalveolar lavage (BAL).
Antidepressant-like effect of delta9-tetrahydrocannabinol and other cannabinoids isolated from Cannabis sativa L. http://www.ncbi.nlm.nih.gov/pubmed/20332000
Psychomotor performance in relation to acute oral administration of Delta9-tetrahydrocannabinol and standardized cannabis extract in healthy human subjects. http://www.ncbi.nlm.nih.gov/pubmed/19224107
Effect of intrapulmonary tetrahydrocannabinol administration in humans http://www.ncbi.nlm.nih.gov/pubmed/18515447
Inhibition of monoamine oxidase activity by cannabinoids http://www.ncbi.nlm.nih.gov/pubmed/20401651
Effect of cannabinoids on platelet serotonin uptake http://www.ncbi.nlm.nih.gov/pubmed/17508987
Cannabinoids promote embryonic and adult hippocampus neurogenesis and produce anxiolytic- and antidepressant-like effects http://www.ncbi.nlm.nih.gov/pubmed/16224541
Intra-dorsal periaqueductal gray administration of cannabidiol blocks panic-like response by activating 5-HT1A receptors http://www.ncbi.nlm.nih.gov/pubmed/20457188
Cannabinoids Potentiate Emotional Learning Plasticity in Neurons of the Medial Prefrontal Cortex through Basolateral Amygdala Inputs http://www.ncbi.nlm.nih.gov/pubmed/16775133
Exogenous acylethanolamides and digestive system health
Cannabis has been used to treat gastrointestinal (GI) conditions that range from enteric infections and inflammatory conditions to disorders of motility, emesis and abdominal pain. Anatomical, physiological and pharmacological studies have shown that the endocannabinoid system is widely distributed throughout the gut, with regional variation and organ-specific actions. It is involved in the regulation of food intake, nausea and emesis, gastric secretion and gastroprotection, GI motility, ion transport, visceral sensation, intestinal inflammation and cell proliferation in the gut. Modulation of acylethanolamide levels in the gut may provide new pharmacological strategies not only for the treatment of feeding disorders but also for the prevention or cure of widespread intestinal diseases such as inflammatory bowel disease and colon cancer.
Patented FAAH inhibitor does everything cannabis does, plus.
Amines that inhibit a mammalian anandamide transporter, and methods of use thereof United States Patent Application 20060281742 One aspect of the present invention relates to amines
Quantum Matter goldennumber.net Artists use Phi and the Golden Section to achieve beauty and balance in layout and design.
Golden ratio discovered in quantum world: Hidden symmetry observed for the first time in solid state
www.sciencedaily.com
Researchers have for the first time observed a nanoscale symmetry hidden in solid state matter. They have measured the signatures of a symmetry showing the same attributes as the golden ratio famous from art and architecture.
Experiments show that soil and foliar application of zinc fertilizer can effectively reduce the phytate zinc ratio in grain. People who eat bread prepared from zinc enriched wheat show a significant increase in serum zinc, suggesting that the zinc fertilizer strategy is a promising approach to address zinc deficiencies in humans.
In animal studies, rats who were deprived of zinc during early fetal development exhibited increased emotionality, poor memory, and abnormal response to stress which interfered with performance in learning situations. Zinc deprivation in monkeys showed that zinc deficient animals were emotionally less mature, and also had cognitive deficits indicated by their difficulty in retaining previously learned problems and in learning new problems. Human observational studies show weaker results. Low maternal zinc status has been associated with less attention during the neonatal period and worse motor functioning.
Deficiencies of micronutrients (zinc, iron, folic acid and iodine) during pregnancy are known causes of Low Birth Weight (LBW). Studies have documented status of one or two micronutrients amongst pregnant women (PW). However, no attempt has been made to concurrently assess the prevalence of multiple micronutrient deficiencies and the factors associated with them amongst PW.
Nearly 73.5, 2.7, 43.6, 73.4, 26.3, and 6.4 percent PW were deficient in zinc, copper, magnesium, iron, folic acid and iodine, respectively. The highest concurrent prevalence of two, three, four and five micronutrient deficiency was of zinc and iron (54.9%); zinc, magnesium and iron (25.6%); zinc, magnesium, iron and folic acid (9.3%) and zinc, magnesium, iron, folic acid and iodine (0.8%), respectively. No pregnant woman was found to have concomitant deficiencies of all the six micronutrients. Dietary intake data revealed an inadequate nutrient intake. Over 19% PW were consuming less than 50% of the recommended calories. Similarly, 99, 86.2, 75.4, 23.6, 3.9 percent of the PW were consuming less than 50% of the recommended folic acid, zinc, iron, copper, and magnesium. The consumption of food groups rich in micronutrients (pulses, vegetables, fruits, nuts and oil seeds, animal foods) was infrequent. Univariate and Multivariate logistic regression analysis revealed that low dietary intake of nutrients, low frequency of consumption of food groups rich in micronutrients and increased reproductive cycles with short interpregnancy intervals were important factors leading to micronutrient deficiencies.
Pulses (beans) are 20 to 25% protein by weight, which is double the protein content of wheat and three times that of rice. For this reason, pulses are called "vegetarian's meat". While pulses are generally high in protein, and the digestibility of that protein is also high, they often are relatively poor in the essential amino acid methionine, although Indian cuisine includes sesame seeds, which contain high levels of methionine. Grains (which are themselves deficient in lysine) are commonly consumed along with pulses to form a complete protein of diet.
Nutritional Programming in the Rat Is Linked to Long-Lasting Changes in Nutrient Sensing and Energy Homeostasis in the Hypothalamus
The programming of the hypothalamic circuits regulating energy homeostasis is a key step in the development of obesity associated with malnutrition in early life
http://www.biospace.com/PLos_Article.aspx?TheTitle=Nutritional+Programming+in+the+Rat+Is+Linked+to+Long-Lasting+Changes+in+Nutrient+Sensing+and+Energy+Homeostasis+in+the+Hypothalamus
BioSpace - Nutritional Programming in the Rat Is Linked to Long-Lasting Changes in Nutrient Sensing.
Drug Discovery Opinion » PF-3845 – A Potent and Selective FAAH Inhibitor
drugdiscoveryopinion.com
The discovery of the cannabis receptors CB1 and CB2 and the subsequent discovery of anandamide (N-arachidonoylethanolamine), the first endogenous agonist of both receptors, provided a rationale for the known analgesic properties of Cannabis sativa.
http://www.sciencedaily.com/releases/2007/11/071105120556.htm
Marijuana-like Brain Chemicals Work As Antidepressant
www.sciencedaily.com
Researchers have found that boosting the amounts of a marijuana-like brain transmitter called anandamide produces antidepressant effects in test rats.
http://www.caymanchem.com/app/template/Product.vm/catalog/10046/a/z
http://learnmem.cshlp.org/content/16/5/332.full
Fatty acid amide hydrolase (FAAH) inhibition enhances memory acquisition through activation of PPAR-α nuclear receptors
http://www.ncbi.nlm.nih.gov/pubmed/18172430
http://www.pnas.org/content/102/51/18620.full#ref-18
http://www.caymanchem.com/app/template/Product.vm/catalog/10046/a/z
http://www.ncbi.nlm.nih.gov/pubmed/20850463
The future of marijuana in pill form via raising anandamide [0026] Fatty acid amide hydrolase (FAAH) is an enzyme that hydrolyzes the fatty acid amide (FAA) family of endogenous signaling lipids. General classes of FAAs include the N- acylethanolamines (NAEs) and fatty acid primary amides (FAPAs)
Cannabis and Cancer
Cannabinoids, the active components of Cannabis sativa (marijuana) and their endogenous counterparts, exert their effects by binding to specific G-protein-coupled receptors that modulate adenylyl cyclase and ion channels
Japan to Beam Solar Power from Space on Lasers
www.foxnews.com
Japan is aiming to collect solar power in space and zap it down to Earth using laser beams or microwaves. The government has picked companies and researchers to turn the multi-billion pound dream of unlimited clean energy into reality by 2030.
http://www.ncbi.nlm.nih.gov/pubmed/17397266
The common cold is the leading cause of doctor visits in the United States and annually results in 189 million lost school days. In the course of one year the U.S. population contracts approximately 1 billion colds. Influenza infection is still a leading cause ofmorbidity and mortality, accounting for 20-25 million doctor visits and 36,000 deaths per year in the United States. Conventional therapies for colds and flu focus primarily on temporary symptom relief and include over-the-counter antipyretics, anti-inflammatories, and decongestants. Treatment for influenza also includes prescription antiviral agents and vaccines for prevention. This article reviews the common cold and influenza viruses, presents the conventional treatment options, and
highlights select botanicals (Echinacea spp., Sambucus nigra, larch arabinogalactan, Astragalus membranaceous, Baptisia tinctoria, Allium sativa, Panax quinquefolium, Eleutherococcus senticosus, Andrographis paniculata, olive leaf extract, and Isatis tinctoria) and nutritional considerations (vitamins A and C, zinc, high lactoferrin whey protein, N-acetylcysteine, and DHEA) that may help in the prevention and treatment of these conditions.
http://www.dadamo.com/science_larch.htm
Peter D'Adamo: Larch Arabinogalactan is a Novel Immune Modulator
www.dadamo.com
Information, guidance and support for readers interested in applying the principles of The Blood Type Diet as outlined by The New York Times best-selling author Dr. Peter D'Adamo.
This indicates that disrupting cannabinoid 1 receptor-mediated neurotransmission at the genome level produces mutant mice with an enhanced capacity to strengthen synaptic connections in a brain region crucial for memory formation.
http://www.ncbi.nlm.nih.gov/pubmed/10619457?dopt=Abstract
NewsDaily: North Korea military appears to back Kim succession
www.newsdaily.com
North Korea's military has nominated the third son of ailing leader Kim Jong-il as a delegate to a rare meeting of the ruling party, a South Korean newspaper said, supporting reports he is his father's chosen successor.
http://www.harmreductionjournal.com/content/2/1/17
Harm Reduction Journal | Full text | Harm reduction-the cannabis paradox
www.harmreductionjournal.com
The electronic version of this article is the complete one and can be found online at: http://www.harmreductionjournal.com/content/2/1/17
September 27, 2010 at 2:08am · LikeUnlike · · Share
http://www.uccs.edu/~rmelamed/Evolutionism/medical_uses_of_cannabinoid_2/
Medical Uses of Cannabinoids | Evolutionism | Dr. Bob Melamede
www.uccs.edu
Endocannabinoids are currently being intensively investigated by scientists around the world as their intimate involvement in human health is revealed. Below are selected abstracts from PubMed, the NIH database of peer reviewed articles on medicine and biology. There are thousands additional article
A frequent polymorphism in the coding exon of the human cannabinoid receptor (CNR1) gene was detected in codon 453 of the CNR1 gene that turned out to be a common polymorphism in the German population which may be related to anandamide metabolism disturbances. facilitating disorders like Gilles de la Tourette syndrome (GTS), obsessive compulsive disorder (OCD), Parkinsons disease, Alzheimers disease and severe alcohol dependence.
http://en.wikipedia.org/wiki/Shwedagon
Shwedagon Pagoda - Wikipedia, the free encyclopedia
en.wikipedia.org
The Shwedagon Pagoda (Burmese: ရွှေတိဂုံ ဘုရား; MLCTS: hrwe ti. gum. bhu. ra:, IPA: [ʃwèdəɡòuɴ pʰəjá]); Mon:ကျာ် လ္ဂုၚ်, [tɕaiʔ təkɜ̀ŋ]; officially titled Shwedagon Zedi Daw ([ʃwèdəɡòun zèdìdɔ̀]), also known as the Golden Pagoda, is a 98-metre (approx. 321.5 feet) gilded stupa located in Yangon, Bur
http://en.wikipedia.org/wiki/GABA
Memory's Master Switch: Molecular Power Behind Memory Discovered
ScienceDaily (July 29, 2010) —
Neuroscientists have long wondered how individual connections between
brain cells remain diverse and "fit" enough for storing new memories.
Now it looks like I have to do some tests of my own. Mainstream literature always ignores the endocannabinoid system. To my knowledge, endocannabinoids regulate neurogenesis. The amino acid Glutamate gets synthesized to GABA. THC inhibits glutamatergic toxicity and seizures/spasms caused from it. I wonder if some mice had a maxed glutamate and THC during life stages compared to controls they wouldn't find out that cannabis is intrinsically linked. In 2007, an excitatory GABAergic system was described in the airway epithelium. The system activates following exposure to allergens and may participate in the mechanisms of asthma. Cannabis has been used for 5,000 years in similar mechanisms. http://www.cannabismd.net/asthma/
Medical Marijuana - Asthma
www.cannabismd.net
Asthma is the shortness of breath and wheezing caused by spasms of the bronchial tubes, overproduction of mucus, and swelling of the mucous membranes. Asthma kills more than 4,000 Americans each year.[1]
http://www.sciencedaily.com/releases/2010/07/100729144223.htm
GABA regulates the proliferation of neural progenitor cells, the migration and differentiation, the elongation of neurites, and the formation of synapses. http://www.ncbi.nlm.nih.gov/pubmed/12209121
Endocannabinoids, the endogenous counterparts of marijuana-derived cannabinoids, act as neuromodulators via presynaptic CB1 receptors and also control neural cell death and survival. Here we show that progenitor cells express a functional endocannabinoid system that actively regulates cell proliferation both in vitro and in vivo. Specifically, NPs produce endocannabinoids and express the CB1 receptor and the endocannabinoid-inactivating enzyme FAAH. CB1 receptor activation promotes cell proliferation and neurosphere generation, an action that is abrogated in CB1-deficient NPs.
Recent research shows that endocannabinoids stimulate neural progenitor proliferation and inhibit hippocampal neurogenesis in normal adult brain. Cannabinoids inhibit cortical neuron differentiation and promote glial differentiation. On the other hand, experiments with differentiated neurons have shown that cannabinoids also regulate neuritogenesis, axonal growth and synaptogenesis.
http://www.nopalaztec.com/fr_new.php
http://www.ncbi.nlm.nih.gov/pubmed/11322644
Endocannabinoid system - Wikipedia, the free encyclopedia
en.wikipedia.org
The endocannabinoid system refers to a group of neuromodulatory lipids and their receptors that are involved in a variety of physiological processes including appetite, pain-sensation, mood, and memory. It is named for endocannabinoids, the endogenous lipids that bind cannabinoid receptors (the same
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1253627/?tool=pmcentrez
In summary, since adult hippocampal neurogenesis is suppressed following chronic administration of opiates, alcohol, nicotine, and cocaine, the present study suggests that cannabinoids are the only illicit drug that can promote adult hippocampal neurogenesis following chronic administration. Increased hippocampal neurogenesis appears to underlie the mechanism of anxiolytic- and antidepressant-like effects produced by a high dose of chronic HU210 treatment. The opposing effects of high doses of acute and chronic cannabinoids, together with the anxiolytic-like effects caused by a low dose of cannabinoids, may finally explain discrepancies in the clinical study literature regarding the effects of cannabinoid on anxiety and depression.
The discovery of multipotent neural progenitor (NP) cells has provided strong support for the existence of neurogenesis in the adult brain. However, the signals controlling NP proliferation remain elusive. Endocannabinoids, the endogenous counterparts of marijuana-derived cannabinoids, act as neuromodulators via presynaptic CB1 receptors and also control neural cell death and survival. Here we show that progenitor cells express a functional endocannabinoid system that actively regulates cell proliferation both in vitro and in vivo. Specifically, NPs produce endocannabinoids and express the CB1 receptor and the endocannabinoid-inactivating enzyme fatty acid amide hydrolase (FAAH). CB1 receptor activation promotes cell proliferation and neurosphere generation, an action that is abrogated in CB1-deficient NPs. Accordingly, proliferation of hippocampal NPs is increased in FAAH-deficient mice. Our results demonstrate that endocannabinoids constitute a new group of signaling cues that regulate NP proliferation and thus open novel therapeutic avenues for manipulation of NP cell fate in the adult brain.
The endocannabinoids (eCBs) anandamide and 2-arachidonoylglycerol are important retrograde messengers that inhibit neurotransmitter release via presynaptic CB1 receptors. In addition, cannabinoids are known to modulate the cell death/survival decision of different neural cell types, leading to different outcomes that depend on the nature of the target cell and its proliferative/differentiation status. Thus, cannabinoids protect primary neurons, astrocytes and oligodendrocytes from apoptosis, whereas transformed glial cells are prone to apoptosis by cannabinoid challenge. Moreover, a potential role of the eCB system in neurogenesis and neural differentiation has been proposed. Recent research shows that eCBs stimulate neural progenitor proliferation and inhibit hippocampal neurogenesis in normal adult brain. Cannabinoids inhibit cortical neuron differentiation and promote glial differentiation. On the other hand, experiments with differentiated neurons have shown that cannabinoids also regulate neuritogenesis, axonal growth and synaptogenesis. These new observations support that eCBs constitute a new family of lipid signaling cues responsible for the regulation of neural progenitor proliferation and differentiation, acting as instructive proliferative signals through the CB1 receptor.
http://en.wikipedia.org/wiki/Caryophyllene
First Dietary Cannabinoid FDA Approved
en.wikipedia.org
Caryophyllene (pronounced /ˌkæri.ɵfɪˈliːn/), or (−)-β-caryophyllene, is a natural bicyclic sesquiterpene that is a constituent of many essential oils, especially clove oil, the oil from the stems and flowers of Syzygium aromaticum (cloves)[1], the essential oil of hemp Cannabis sativa[2], and rosema
http://www.sciencedaily.com/news/headlines/
ScienceDaily: Latest Science News
www.sciencedaily.com
Breaking science news and articles on global warming, extrasolar planets, stem cells, bird flu, autism, nanotechnology, dinosaurs, evolution -- the latest discoveries in astronomy, anthropology, biology, chemistry, climate & environment, computers, engineering, health & medicine, math, physics, psyc
June Was the Fourth Consecutive Month That Was Warmest on Record
http://www.sciencedaily.com/releases/2010/07/100718233311.htm
Autophagy can promote cell survival or cell death, but the molecular basis underlying its dual role in cancer remains obscure. Here we demonstrate that Δ9-tetrahydrocannabinol (THC), the main active component of marijuana, induces human glioma cell death through stimulation of autophagy. Our data indicate that THC induced ceramide accumulation and eukaryotic translation initiation factor 2α (eIF2α) phosphorylation and thereby activated an ER stress response that promoted autophagy via tribbles homolog 3–dependent (TRB3-dependent) inhibition of the Akt/mammalian target of rapamycin complex 1 (mTORC1) axis. We also showed that autophagy is upstream of apoptosis in cannabinoid-induced human and mouse cancer cell death and that activation of this pathway was necessary for the antitumor action of cannabinoids in vivo. These findings describe a mechanism by which THC can promote the autophagic death of human and mouse cancer cells and provide evidence that cannabinoid administration may be an effective therapeutic strategy for targeting human cancers.
Journal of Clinical Investigation -- Cannabinoid action induces autophagy-mediated cell death throu
Our data indicate that THC induced ceramide accumulation
As a bioactive lipid, ceramide has been implicated in a variety of physiological functions including apoptosis, cell growth arrest, differentiation, cell senescence, cell migration and adhesion. Roles for ceramide and its downstream metabolites have also been suggested in a number of pathological states including cancer, neurodegeneration, diabetes, microbial pathogenesis, obesity, and inflammation.
Ceramide accumulation has been found following treatment of cells with a number of apoptotic agents including ionizing radiation, UV light, TNF-alpha, and chemotherapeutic agents. This suggests a role for ceramide in the biological responses of all these agents. Because of its apoptosis-inducing effects in cancer cells, ceramide has been termed the “tumor suppressor lipid”
This is incredible news. Cannabis performs the same effect that is attempted in chemotherapy - the accumulation of the tumor suppressor lipid. Cannabis however provides this treatment to every organ system at once, maxing the micrograms per micromole of THC around all the cells that are to die. This makes sure they dont stay alive past a healthy programmed cell death and turn into tumors.
http://www.naturalnews.tv/v.asp?v=BCED96C19361449686F6E68ED178FFFF
Foods That Kill - Part 1 of 6 - NaturalNews.tv
www.naturalnews.tv
Make Yourself Heart Attack Proof http://www.youtube.com/watch?v=AYTf0z Herbivore vs. Carnivore - You be the judge ! http://www.bizarro.com/videos/mov/Veg Explore the consequences of a me
ScienceDaily (June 23, 2010) Neuroscientists Can Predict Your Behavior Better Than You Can
Neuroscientists can predict your behavior better than you can
www.sciencedaily.com
In a study with implications for the advertising industry and public health organizations, neuroscientists have shown they can use brain scanning to predict whether people will use sunscreen in the next week better than the people themselves can predict whether they will do so. This is the first per
Electrifying food while it is being cooked could be major breakthrough
www.gizmag.com
American cookware manufacturer LifeWare Technologies has announced the launch of a new line of cookware that it claims electromechanically reduce
THC deficiency by Ethan Russo
In the initial lines of his 1895 work, Project for a Scientific Psychology, Sigmund Freud stated [1] (p..
http://www.gizmag.com/axle-group-ev-x7-electric-motorcycle/8403/
EV-X7: the electric future-cruiser
www.gizmag.com
With an only in Japan style unlike anything that’s come before it, the EV-X7 is an electric streetbike with a 92mph top speed and a range of up
http://www.gizmag.com/asus-eeekeyboard-official-announcement/14970/
ASUS Eee Keyboard PC officially launched (at last)
www.gizmag.com
ASUS has finally launched its Eee Keyboard PC, although confirmation of price and release date are still unknown
http://www.mag-i-cal.com/magnesium.htm
Magnesium dietary supplement in Nano Particle Ionic Liquid form.
www.mag-i-cal.com
magnesium deficiencies and needs addressed with Nano Particle Ionic Liquid Magnesium supplement, a high potency form of 100% absorbable ionic magnesium.
http://www.sciencedaily.com/articles/c/cannabis.htm
Cannabis
www.sciencedaily.com
As a drug it usually comes in the form of dried flowers (marijuana), resin (hashish), or various extracts collectively referred to as hash oil..
We find that variation in the transcript levels of the brain gene syntaxin 1a correlates significantly with intelligence!
Thus, the closed conformation of syntaxin-1 gates the initiation of the synaptic vesicle fusion reaction, which is then mediated by SNARE-complex/Munc18-1 assemblies.
http://www.cheniere.org/briefings/porthole/index.htm
The Tom Bearden Website
www.cheniere.org
‎"A consortium of the scientific community, the large pharmaceuticals, FDA, and the AMA will oppose this project even while the U.S. is being destroyed wholesale."
http://audiospotlights.com/directional_sound_intro.html
Audio_Spotlights: Introduction to hypersonic sound directional sound beam technology: How does it wo
audiospotlights.com
Audio Spotlight and Hypersonic Sound. An introduction to directional beams of sound. How does it work? What are we doing with it?
http://www.amazing1.com/burning-lasers.htm
Class 4 Burning, Cutting Lasers
www.amazing1.com
Information Unlimited -Class 4 Burning, Cutting Lasers
Our data indicate that THC induced ceramide accumulation and eukaryotic translation initiation factor 2a phosphorylation and thereby activated an ER stress response that promoted autophagy via tribbles homolog dependent inhibition of the mTORC1 axis
http://www.jci.org/articles/view/37948
Marijuana prevents lung cancer
Journal of Clinical Investigation -- Cannabinoid action induces autophagy-mediated cell death throug
www.jci.org
‎(May 1, 2009)J Clin Invest. 2009;119(5):1359–1372. doi:10.1172/JCI37948.Copyright © 2009, American Society for Clinical Investigation
Termites release more co2 than humans annually. Mt. St. Helens released more greenhouse gas than all of humanity since the industrial revolution began.
30,000 Scientists Rejecting Anthropomorphic Global Warming Hypothesis « What The Crap?
whatthecrap.wordpress.com
Uhhad a slight weapons malfunction. But, uh, everything's perfectly all right now. We're fine. We're all fine here, now, thank you. How are you? - Han Solo
Mt. St. Helens (only VEI-3 of VEI-8, scaling by x10 each level in cubic kilometers of the ash cloud) was 1/100,000th the size of the eruptions we get several times every 10 million years.
http://en.wikipedia.org/wiki/Biefield-Brown_effect
Check out the Ionic Airfish
Plasma Aerodynamics
www.electrofluidsystems.com
In 1998, Berkant Goeksel founded theFuture WorkshopElectrofluidsystems at the Technical University of Berlinwith the vision of developing plasma assisted flight vehicles forfuture generation.
www.zimbio.com
With reports suggesting the budget for the world's most advanced fusion reactor is growing as the time-table is pushed back, ITER officials insist the project is still on target. (Reuters Business Video)
International Thermonuclear Experimental Reactor
http://en.wikipedia.org/wiki/Iter
http://www.msnbc.msn.com/id/7285683/
Salba® - Nature's Most Powerful Whole Food
www.sourcesalba.com
The whole food Salba® is derived from an ancient variety of plant species belonging to the mint family called Chia. Its botanical name is Salvia hispanica L. Chia was an integral cornerstone of the daily diet that fueled the vast Aztec empire.
The average human brain contains approximately 100 billion neurons and tens of billions of additional support cells called glia, with average daily loss of 200,000 neurons (equates to 1/500,000th daily or 0.0002%, discounting glia). we also live from 28,000 to 40,000 days. 86,400 seconds a day means 1 neuron is lost every 26 seconds. 40,000 days is 960,000 hours, and the age of 114 reaches the million mark. 114 years is 2.28% of our total neurons natural decay in contemporary standards (little to no supplementation).

Action of Nrf2 and Keap1 in ARE-mediated NQO1 expression by quercetin.

2011-04-19T19:02:00.000-07:00

Polyphenols are characterized by the presence of more than one phenolic group and are widely distributed in many fruits and vegetables. They possess antioxidant properties and interact with cellular defense systems through the antioxidant-responsive element/electrophile-responsive element (ARE/EpRE) although the precise mechanism by which polyphenols influence transcription factor complexes to target ARE is poorly understood. In the present study, we chose a typical polyphenol, quercetin, to investigate the mechanism in human HepG2 cells. Quercetin enhanced the ARE binding activity and Nrf2-mediated transcription activity. Molecular evidence revealed that quercetin not only up-regulated the expression of Nrf2 mRNA and protein, but also stabilized Nrf2 protein by inhibiting the ubiquitination and proteasomal turnover of Nrf2. At the same time, quercetin markedly reduced the level of Keap1 protein in posttranslational levels through the formation of modified Keap1 protein, rather than 26S proteasome-dependent degradation mechanisms, without affecting the dissociation of Keap1-Nrf2. Silencing Keap1 using Keap1 siRNA significantly increased the Nrf2-dependent ARE activity, whereas silencing Nrf2 using Nrf2 siRNA markedly reduced the ARE activity under both baseline and quercetin-induced conditions. Thus, we conclude that the pathway of quercetin-induced ARE activity involves up-regulation of Nrf2 through the regulation of both transcription and posttranscription sites and repression of Keap1 by affecting the posttranscription site, revealing some substantial differences between oxidative inducers. Thus, the findings provide an insight into the mechanisms underlying polyphenolic compounds in cytoprotection and cancer chemoprevention.

Regulation of human carbonyl reductase 3 (CBR3; SDR21C2) expression by Nrf2 in cultured cancer cells.

2011-04-19T18:19:00.001-07:00

Carbonyl reduction is a central metabolic process that controls the level of key regulatory molecules as well as xenobiotics. Carbonyl reductase 3 (CBR3; SDR21C2), a member of the short-chain dehydrogenase/reductase (SDR) superfamily, has been poorly characterized so far, and the regulation of its expression is a complete mystery. Here, we show that CBR3 expression is regulated via Nrf2, a key regulator in response to oxidative stress. In human cancer cell lines, CBR3 mRNA was expressed differentially, ranging from very high (A549, lung) to very low (HT-29, colon; HepG2, liver) levels. CBR3 protein was highly expressed in SW-480 (colon) cells but was absent in HCT116 (colon) and HepG2 cells. CBR3 mRNA could be induced in HT-29 cells by Nrf2 agonists [sulforaphane (SUL, 7-fold) and diethyl maleate (DEM, 4-fold)] or hormone receptor ligand Z-guggulsterone (5-fold). Aryl hydrocarbon receptor agonist B[k]F failed to induce CBR3 mRNA after incubation for 8 h but elevated CBR3 levels after 24 h, most likely mediated by B[k]F metabolites that can activate Nrf2 signaling. Inhibition of Nrf2-activating upstream kinase MEK/ERK by PD98059 weakened DEM-mediated induction of CBR3 mRNA. Proteasome inhibitors MG-132 (5 μM) and bortezomib (50 nM) dramatically increased the level of CBR3 mRNA, obviously because of the increase in the level of Nrf2 protein. While siRNA-mediated knockdown of Nrf2 led to a decrease in the level of CBR3 mRNA in A549 cells (30% of control), Keap1 knockdown increased the level of CBR3 mRNA expression in HepG2 (9.3-fold) and HT-29 (2.7-fold) cells. Here, we provide for the first time evidence that human CBR3 is a new member of the Nrf2 gene battery.

t-Butylhydroperoxide-induced Ca2+ efflux from liver mitochondria in the presence of physiological concentrations of Mg2+ and ATP.

2011-04-19T18:14:00.000-07:00

Isolated rat liver mitochondria, energized either by succinate oxidation or by ATP hydrolysis, present a transient increase in the rate of Ca2+ efflux concomitant to NAD(P)H oxidation by hydroperoxides when suspended in a medium containing 3 mM ATP, 4 mM Mg2+ and acetate as permeant anion. This is paralleled by an increase in the steady-state concentration of extramitochondrial Ca2+, a small decrease in delta psi and an increase in the rate of respiration and mitochondrial swelling. With the exception of mitochondrial swelling all other events were found to be reversible. If Ca2+ cycling was prevented by ruthenium red, the changes in delta psi, the rate of respiration and the extent of mitochondrial swelling were significantly diminished. In addition, there was no significant decrease in the content of mitochondrial pyridine nucleotides. Mitochondrial coupling was preserved after a cycle of Ca2+ release and re-uptake under these experimental conditions. It is concluded that hydroperoxide-induced Ca2+ efflux from intact mitochondria is related to the redox state of pyridine nucleotides.

Sublethal oxidant stress induces a reversible increase in intracellular calcium dependent on NAD(P)H oxidation in rat alveolar macrophages.

2011-04-19T18:12:00.001-07:00

A concentration-dependent elevation of intracellular calcium ([Ca2+]i) and oxidation of NAD(P)H occurred in alveolar macrophages during exposure to sublethal tert-butylhydroperoxide concentrations (tBOOH) (< or = 100 microM in 1 ml with 1 x 10(6) cells). Oxidation of NAD(P)H preceded a rise in [Ca2+]i. The elevation of [Ca2+]i was reversible at < 50 microM tBOOH exposure and the return to the steady state [Ca2+]i correlated temporally with repletion of NAD(P)H. At > 50 microM tBOOH, the changes in NAD(P)H and [Ca2+]i were sustained. The relative contributions of NADPH and NADH oxidation were examined by varying the substrates supplying reducing equivalents and by inhibiting glutathione reductase activity. The results suggested that at < 50 microM tBOOH, oxidation of NADPH predominated, while at > 50 microM tBOOH, NADH oxidation predominated. A complex relationship between the relative roles of NADPH and NADH oxidation and the elevation of [Ca2+]i was revealed: (i) reversible oxidation of NADPH is associated with the initial and reversible elevation of [Ca2+]i at < 50 microM tBOOH; (ii) the sustained elevation of [Ca2+]i at > 50 microM tBOOH correlates with the sustained oxidation of NADH; and (iii) the changes in [Ca2+]i did not depend on influx of extracellular Ca2+. We speculate that at low tBOOH, Ca2+ was released from the NADPH/NADP(+)-sensitive mitochondrial Ca2+ pool while higher tBOOH caused additional Ca2+ release from GSH/GSSG-sensitive nonmitochondrial Ca2+ pools with sustained elevation of [Ca2+]i due to decreased mitochondrial Ca2+ reuptake.

Effect of peroxide, sodium, and calcium on brain mitochondrial respiration in vitro: potential role in cerebral ischemia and reperfusion

2011-04-19T18:09:00.000-07:00

Mitochondrial pyruvate-supported respiration was studied in vitro under conditions known to exist following ischemia, i.e., elevated extramitochondrial Ca2+, Na+, and peroxide. Ca2+ alone (7-10 nmol/mg) decreased state 3 and increased state 4 respiration to 81 and 141% of control values, respectively. Sodium (15 mM) and/or tert-butyl hydroperoxide (tBOOH; up to 2,000 nmol/mg protein) alone had no effect on respiration; however, Na+ or tBOOH in combination with Ca2+ dramatically altered respiration. Respiratory inhibition induced by Ca2+ and tBOOH does not involve pyruvate dehydrogenase (PDH) inhibition since PDH flux increased linearly with tBOOH concentration (R = 0.96). Calcium potentiated tBOOH-induced mitochondrial NAD(P)H oxidation and shifted the redox state of cytochrome b from 67 to 47% reduced. Calcium (5.5 nmol/mg) plus Na+ (15 mM) decreased state 3 and increased state 4 respiratory rates to 55 and 202% of control values, respectively. Sodium- as well as tBOOH-induced state 3 inhibition required mitochondrial Ca2+ uptake because ruthenium red addition before Ca2+ addition negated the effect. The increase in state 4 respiration involved Ca2+ cycling since ruthenium red immediately returned state 4 rates back to control values. The mechanisms for the observed Ca2(+)-, Na(+)-, and tBOOH-induced alterations in pyruvate-supported respiration in vitro are discussed and a multifactorial etiology for mitochondrial respiratory dysfunction following cerebral ischemia in vivo is proposed.

Brain mitochondria from rats treated with sulforaphane are resistant to redox-regulated permeability transition.

2011-04-19T18:06:00.000-07:00

Oxidative stress promotes Ca2+-dependent opening of the mitochondrial inner membrane permeability transition pore (PTP), causing bioenergetic failure and subsequent cell death in many paradigms, including those related to acute brain injury. One approach to pre-conditioning against oxidative stress is pharmacologic activation of the Nrf2/ARE pathway of antioxidant gene expression by agents such as sulforaphane (SFP). This study tested the hypothesis that administration of SFP to normal rats increases resistance of isolated brain mitochondria to redox-sensitive PTP opening. SFP or DMSO vehicle was administered intraperitoneally to adult male rats at 10 mg/kg 40 h prior to isolation of non-synaptic brain mitochondria. Mitochondria were suspended in medium containing a respiratory substrate and were exposed to an addition of Ca2+ below the threshold for PTP opening. Subsequent addition of tert-butyl hydroperoxide (tBOOH) resulted in a cyclosporin A-inhibitable release of accumulated Ca2+ into the medium, as monitored by an increase in fluorescence of Calcium Green 5N within the medium, and was preceded by a decrease in the autofluorescence of mitochondrial NAD(P)H. SFP treatment significantly reduced the rate of tBOOH-induced Ca2+ release but did not affect NAD(P)H oxidation or inhibit PTP opening induced by the addition of phenylarsine oxide, a direct sulfhydryl oxidizing agent. SFP treatment had no effect on respiration by brain mitochondria and had no effect on PTP opening or respiration when added directly to isolated mitochondria. We conclude that SFP confers resistance of brain mitochondria to redox-regulated PTP opening, which could contribute to neuroprotection observed with SFP.

Edited

2011-04-19T17:21:00.001-07:00

The cannabinoid 1 (CB1) receptor antagonist SR141716A reversed the actions of URB-597 and OMDM-2, but not PMSF, without affecting reward thresholds by itself.
THC increases mRNA encoding the immediate early genes zif-268, c-fos and c-jun and FosB protein in the cingulate area of the rat prefrontal cortex.
The DCLHK sequence is conserved in rat, human, mouse and cat CB1 receptors, located in the C-terminal portion of the CB1 receptor in a domain of the protein potentially involved in the interaction with cytoplasmic effectors.
Analysis of these results has led to the suggestion that the effects of SR141716A administration on working memory are dependent on temporal components of the task, and that CB1 blockade may prolong the duration of memory rather than facilitating learning.
SR141716A did not block URB597-mediated attenuation of KA-evoked burst firing.
Cannabis sativa has been known, used, and misused by mankind for centuries, and yet only over the last two decades has research stemming from the chemical constituents specific to this plant, the cannabinoids, started to provide fundamental insights into animal physiology and pathology, resulting in the development of new therapeutics. The discovery of the endocannabinoid system, and its targeting with two new pharmaceutical preparations now on the market in several countries, represent the most recent example of how studies on medicinal plants and on the mechanism of their
biological effects can reveal, through a chain of breakthroughs, new systems of endogenous signals and physiological phenomena that can become the source of novel strategies for unmet therapeutic challenges.
We have developed a new class of agents that prevents anandamide inactivation by targeting the intracellular enzymatic activity
of FAAH. URB597, the most potent member of this class, inhibited FAAH activity with an IC50 value of 4 nM in brain membranes
and 0.5 nM in intact neurons, and an ID50 value of 0.15 mg kg–1 after systemic administration in the rat. This compound
had much greater selectivity for FAAH than other cannabinoid related targets, including cannabinoid receptors (selectivity
index, >25,000) and MGL, an enzyme involved in the deactivation of the endogenous cannabinoid ester 2-AG (selectivity
index, >7,500). Such target discrimination was matched by a lack of overt cannabimimetic effects in vivo. Thus, at doses that almost
abolished FAAH activity and substantially raised brain anandamide levels, URB597 and its analog URB532 did not evoke
catalepsy, reduce body temperature or stimulate feeding, three key symptoms of cannabinoid intoxication in the rodent11.
Nevertheless, the compounds did elicit marked anxiolytic-like responses, which paralleled their ability to inactivate FAAH and
were prevented by the CB1 receptor antagonist rimonabant. We interpret these findings to indicate that URB597 and URB532 may
selectively modulate anxiety-like behaviors by enhancing the tonic actions of anandamide on a subset of CB1 receptors which
may normally be engaged in controlling emotions. Forebrain sites that might be implicated in such actions include the basolateral
amygdala, the anterior cingulate cortex and the prefrontal cortex, all key elements of an “emotion circuit”33 that contains high densities
of CB1 receptors21,22. CB1 receptors in these structures are localized to the axon terminals of a subpopulation of GABAergic
interneurons, which also express the peptide cholecystokinin23,34 (CCK). The anxiogenic properties of CCK35 and the ability of CB1
agonists to inhibit K+-evoked CCK release from hippocampal slices36 indicate that interactions between this peptide and anandamide
may participate in the control of anxiety. In addition to their anxiolytic-like actions, URB597 and
URB532 exerted modest anti-nociception in a model of acute pain, which also was sensitive to CB1 receptor blockade. These findings are similar to those reported for Faah–/– mice9 and support the proposed roles of anandamide in the intrinsic modulation
of pain37. However, as emotional states may strongly influence pain sensation, it is possible that anxiolysis might
have contributed to the mild anti-nociceptive effects of the
FAAH inhibitors. URB597 and URB532 increased brain anandamide levels without
modifying those of the second endogenous cannabinoid, 2-AG. It is therefore likely that the pharmacological actions of
these compounds, which are sensitive to the CB1 antagonist rimonabant,
are primarily due to anandamide accumulation. But the FAAH inhibitors also produced large elevations in the levels
of two anandamide analogs, palmitoylethanolamide and
oleoylethanolamide, whose biological effects are independent of CB1 receptors7,8. Thus, we cannot exclude the possibility that additional properties of URB597 and URB532, mediated by these fatty ethanolamides, remain to be discovered.
We have recently reported that THC induces sphingomyelin breakdown and intracellular ceramide accumulation in primary astrocytes in a timeand
dose-dependent manner (Sa´nchez et al., 1998b; Bla´zquez et al., 1999). Because rat primary astrocytes express the CB1 receptor mRNA (Bouaboula et al., 1995a) and protein
(Sa´nchez et al., 1998a), experiments were conducted to test whether THC-evoked sphingomyelin breakdown was dependent on this receptor. As shown in Fig. 1, the effect of 1 mM
THC was prevented by 1 mM SR141716, a selective CB1 receptor antagonist, but not by 1 mM SR144528, a selective
CB2 receptor antagonist. The synthetic cannabinoid agonist HU-210 at 50 nM also stimulated sphingomyelin hydrolysis.
The endogenous cannabinoid ligand anandamide induced sphingomyelin breakdown at 50 but not at 25 mM. Because
primary astrocytes have a high capacity to take up and degrade anandamide (Di Marzo et al., 1994), we tested the
effect of PMSF, an inhibitor of anandamide hydrolysis, on anandamide action. When coincubated with 100 mM PMSF, 25 mM anandamide was able to evoke maximal sphingomyelin breakdown (Fig. 1). Likewise, methanandamide, a stable synthetic analog of anandamide, induced maximal sphingomyelin hydrolysis at 25 mM, indicating that anandamide action is blunted by cellular degradation. The synthetic CB2 selective agonist JWH-133 at 50 nM did not significantly affect sphingomyelin levels (Fig. 1). Interestingly, although it is well established that cannabinoid receptors are coupled to Gi/o proteins, 50 ng/ml pertussis toxin was unable to prevent THC-induced sphingomyelin breakdown (Fig. 1), whereas under identical experimental conditions, pertussis toxin fully blocked THC-induced activation of extracellular signal-regulated kinase (Bouaboula et al., 1995b) and protein kinase B (Go´mez del Pulgar et al., 2000) (results not shown).
To test whether THC-induced sphingomyelin hydrolysis also occurs in other cells expressing the CB1 receptor, primary
neurons, U373 MG astrocytoma cells, and CHO cells transfected with the CB1 receptor cDNA were examined. However, THC was unable to induce a significant breakdown of sphingomyelin in these cells (Fig. 2).
The Adaptor Protein FAN Couples the CB1 Cannabinoid Receptor of Astrocytes to Sphingomyelin Breakdown.
Extensive studies on the 55-kDa TNF receptor have finely defined the domains of the receptor that allow coupling
to sphingomyelinase activation (Adam-Klages et al., 1998; Kolesnick and Kro¨nke, 1998). A protein designated as FAN
(for factor associated with neutral sphingomyelinase activation) has been shown by Kro¨nke and coworkers (Adam-
Klages et al., 1996; Kreder et al., 1999) to couple the NSD (for
neutral sphingomyelinase activation domain) of the 55-kDa TNF receptor to neutral sphingomyelinase activation. FAN
contains five WD repeats in its C-terminal portion that serve as functional motifs to facilitate defined protein-protein interactions.
Interestingly, b subunits of heterotrimeric G proteins are also WD-repeat proteins (Adam-Klages et al., 1998).
We therefore examined whether the CB1 receptor may be coupled to FAN in primary astrocytes and in U373 MG astrocytoma
cells, the latter selected as an example of cells in which THC is unable to induce sphingomyelin hydrolysis.
For this purpose, the CB1 receptor was precipitated with a specific antibody and FAN was subsequently detected by immunoblotting. As shown in Fig. 3, FAN from primary astrocytes was precipitated by the anti-CB1 receptor antibody. Furthermore, pretreatment of astrocytes with THC favored the binding of FAN to the CB1 receptor, whereas
SR141716 prevented this association. By contrast, the effect of THC was not evident in U373 MG astrocytoma cells, despite
the presence of FAN in these cells. To test whether the FAN-CB1 receptor interaction is functionally
relevant, we used ECV304 cells stably transfected with either full-length FAN or a truncated, dominant-negative
form of FAN that does not bind to the NSD domain of the 55-kDa TNF receptor and therefore blocks TNF-induced
sphingomyelin breakdown and ceramide generation (Adam- Klages et al., 1996; Se´gui et al., 1999). In line with a previous report (Liu et al., 2000), ECV304 cells were shown to express the CB1 receptor (Fig. 4A).
CB1 Cannabinoid Receptor and Sphingomyelin Hydrolysis 957
As shown in Fig. 4B, THC induced a transient breakdown of sphingomyelin in cells expressing
wild-type FAN but not in cells expressing dominant-negative FAN. The involvement of the CB1 receptor in THC-induced sphingomyelin hydrolysis was proved by the antagonistic effect of SR141716. As expected, THC-induced sphingomyelin breakdown occurred in concert with an elevation of intracellular ceramide levels (Fig. 4C). HU-210 also induced sphingomyelin hydrolysis in ECV304 cells expressing wildtype FAN, and this effect was prevented by SR141716 (results not shown).
The notion that FAN is coupled to the CB1 receptor is strengthened by the homology between the NSD of the 55-
kDa TNF receptor and a region of the CB1 cannabinoid receptor. NSD is a short, nine-amino-acid motif that includes
the sequence DSAHK (Adam-Klages et al., 1996), and the CB1 receptor contains the highly homologous sequence
DCLHK at amino acid positions 431 to 435 (Matsuda et al., 1990). The DCLHK sequence 1) is conserved in rat, human, mouse and cat CB1 receptors is located in the C-terminal portion of the CB1 receptor (i.e., in a domain of the protein potentially involved in the interaction with cytoplasmic effectors); and 3) is not
present in the CB2 receptor, which, in HL-60 cells at least, is not coupled to sphingomyelin hydrolysis (results not shown).
It is difficult to evaluate whether the aforementioned sequence homology between the NSD of the 55-kDa TNF receptor and the NSD-like portion of the CB1 receptor is actually significant. In this respect, it is worth noting that CD40, a member of the TNF receptor superfamily, has been recently shown to evoke sphingomyelin hydrolysis via FAN (Se´gui et al., 1999). The sequence QETLH in the cytoplasmic domain of
CD40, the one that fits better with a portion of the NSD of the 55-kDa TNF receptor (EDSAH), shares a lower similarity with the latter than the CB1 receptor. Nevertheless, as we are aware, because the CB1 receptor is not coupled to FAN in U373 MG astrocytoma cells, which express FAN, additional, still-unknown factors may be necessary for the CB1 receptor to activate sphingomyelin hydrolysis.
The sphingomyelin cycle plays and important role in the regulation of cell physiology in the central nervous system
(Kolesnick and Kro¨nke, 1998). Ceramide generated by challenge of astroglial cells to cannabinoids may serve as a second messenger in the control of several functions [e.g., metabolic regulation (Sa´nchez et al., 1998b; Bla´zquez et al., 1999) and induction of apoptosis (Galve-Roperh et al., 2000)]. The notion that the CB1 cannabinoid receptor, like the 55- kDa TNF receptor, may control the activity of the sphingomyelin cycle (the present report) and of mitogen- (Bouaboula et al., 1995b) and stress-activated protein kinases (Rueda et al., 2000) points to a general role of cannabinoids as modulators of glial cell fate. By showing that the CB1 cannabinoid receptor may be coupled to FAN independently of Gi/o proteins, this report opens a new conceptual view on the mechanism
of cannabinoid action and contributes to the novel idea that G protein-coupled receptors may signal via ceramide
(Limatola et al., 1999) as well as by mechanisms alternative to the classical heterotrimeric-G protein paradigm (Hall et
al., 1999).
CB1 receptors are involved in the control of excitatory glutamatergic neurotransmission. Blockade
of AEA metabolism could therefore confer inhibitory effects via suppression of excitatory synapses under hyperexcitable conditions.
AEA has been shown to directly modulate a number of seven-transmembrane and nuclear receptors, including GPR55 and peroxisome proliferator-activated receptors (reviewed in Alexander and Kendall, 2007), and voltage and ligand-gated ion channels, in some cases at intracellular sites, including T-type calcium channels, voltage-gated, and background potassium channels, a7-nicotinic acetylcholine receptors, TRPV1 receptors, and 5-HT3 serotonin receptors.
This work found that administration of a CB1 antagonist during febrile seizures blocked seizure induced potentiation of DSI, eliminated seizure-induced CB1 receptor upregulation, and prevented the development of long-term limbic hyperexcitability.
Furthermore, this study indicates that by inhibiting the degradation of AEA and other endocannabinoids, specific FAAH inhibitors such as URB597 may provide us with new hope for effectively lowering IOP by enhancing aqueous humor outflow.
Results indicate that ACEA (2.5 mg/kg, i.p.) co-administered with PMSF (30 mg/kg, i.p.), significantly enhanced the anticonvulsant activity of phenobarbital.
THC induced a transient breakdown of sphingomyelin in cells expressing dominant-negative factor associated with neutral sphingomyelinase activation.
As expected, THC-induced sphingomyelin breakdown occurred in concert with an elevation of intracellular ceramide levels.
THC increases mRNA encoding the immediate early genes zif-268, c-fos and c-jun and FosB protein in the cingulate area of the rat prefrontal cortex.
THC-induced working memory deficits in a delayed alternation T-maze task are associated with altered dopamine and noradrenaline turnover in the rat prefrontal cortex.
Rats must shift attentional bias (or ‘set’) between different abstract features of stimuli, a process termed ‘attentional set shifting’. In contrast, in order to perform reversal-learning discriminations, rats must update contingencies between stimuli and reward presentation when these are reversed. Acute administration of D9-THC impairs performance on reversal learning stages of the task, whilst attentional set shifting ability is unaffected.
Initial evidence that antagonism of CB1 receptors may improve certain memory processes was obtained using an olfactory recognition task. As mature rodents normally spend more time investigating unfamiliar than familiar conspecific animals, the olfactory recognition task measures social short-term working memory capacity. In this task, administration of SR141716A alone improves olfactory recognition memory in both aged rats and mice. In addition, SR141716A improves working memory performance on the 8-arm radial maze when long delay periods are included. These studies have therefore, suggested that SR141716A may exert nootropic effects when administered alone, and, by extension, indicate that the endocannabinoid system may negatively influence some mnemonic processes.
Analysis of these results has led to the suggestion that the effects of SR141716A administration on working memory are dependent on temporal components of the task, and that CB1 blockade may prolong the duration of memory rather than facilitating learning.
SR141716A did not block URB597-mediated attenuation of KainicAcid-evoked burst firing.
CB1 receptors are involved in the control of excitatory glutamatergic neurotransmission. Blockade
of AEA metabolism could therefore confer inhibitory effects via suppression of excitatory synapses under hyperexcitable conditions.
AEA has been shown to directly modulate a number of seven-transmembrane and nuclear receptors, including GPR55 and peroxisome proliferator-activated receptors (reviewed in Alexander and Kendall, 2007), and voltage and ligand-gated ion channels, in some cases at intracellular sites, including T-type calcium channels, voltage-gated, and background potassium channels, a7-nicotinic acetylcholine receptors, TRPV1 receptors, and 5-HT3 serotonin receptors.
We examined cardiovascular responses to intravenous administration of anandamide and the synthetic cannabinoid, (WIN55212-2), in conscious male Wistar rats made acutely hypertensive by infusion of angiotensin II (AII) and arginine vasopressin (AVP). Rats were chronically instrumented for measurement of arterial blood pressure and vascular conductances in the renal, mesenteric and hindquarters beds.
Anandamide dose-dependently decreased the mean arterial blood pressure of rats made hypertensive by AII-AVP infusion, but not normotensive rats. Interestingly, acute hypertension also revealed a hypotensive response to WIN55212-2, which caused hypertension in normotensive animals. The enhanced depressor effects of the cannabinoids in acute hypertension were associated with increased vasodilatation in hindquarters, renal and mesenteric vascular beds. Treatment with URB597, which inhibits anandamide degradation by fatty acid amide hydrolase, potentiated the depressor and mesenteric vasodilator responses to anandamide. Furthermore, haemodynamic responses to WIN55212-2, but not to anandamide, were attenuated by the CB1 receptor antagonist, AM251.
The sphingomyelin cycle plays and important role in the regulation of cell physiology in the central nervous system. Ceramide generated by challenge of astroglial cells to cannabinoids may serve as a second messenger in the control of several functions [e.g., metabolic regulation and induction of apoptosis. The notion that the CB1 cannabinoid receptor, like the 55- kDa TNF receptor, may control the activity of the sphingomyelin cycle and of mitogen-and stress-activated protein kinases points to a general role of cannabinoids as modulators of glial cell fate. By showing that the CB1 cannabinoid receptor may be coupled to FAN independently of Gi/o proteins, this report opens a new conceptual view on the mechanism of cannabinoid action and contributes to the novel idea that G protein-coupled receptors may signal via ceramide as well as by mechanisms alternative to the classical heterotrimeric-G protein paradigm.
This work found that administration of a CB1 antagonist during febrile seizures blocked seizure induced potentiation of DSI, eliminated seizure-induced CB1 receptor upregulation, and prevented the development of long-term limbic hyperexcitability.
Furthermore, this study indicates that by inhibiting the degradation of AEA and other endocannabinoids, specific FAAH inhibitors such as URB597 may provide us with new hope for effectively lowering IOP by enhancing aqueous humor outflow.
But the FAAH inhibitors also produced large elevations in the levels of two anandamide analogs, palmitoylethanolamide and oleoylethanolamide, whose biological effects are independent of CB1 receptors.
Other members of the acylethanolamide lipid family are also produced by neurons and act through
G-protein-coupled receptors: homo-linolenylethanolamide (HEA) and docosatetraenylethanolamide (DEA) act through CB1 receptors
A number of studies indicate that cannabinoids impair memory acquisition in mammals by suppressing
excitation in the hippocampus, one consequence of which is that hippocampal neural activity remains
below levels required for long-term potentiation (LTP; Terranova et al., 1995; Stella et al., 1997;
Hampson and Deadwyler, 2000; Sullivan; 2000). That is, activation of CB1 receptors impairs LTP via inhibition
of presynaptic calcium channels, thereby reducing excitatory neurotransmitter release below levels
that are required to remove the magnesium block from postsynaptic NMDA receptors (Misner and Sullivan,
1999; Sullivan, 1999; Hoffman and Lupica, 2000).
Prior work has shown that cannabinoid exposure of zebra finches during sensorimotor stages of vocal development alters song patterns produced in adulthood. We are currently working to identify physiological substrates for this altered song learning. FoxP2 is a transcription factor associated with altered vocal development in both zebra finches and humans. This protein shows a distinct pattern of expression within Area X of striatum that coincides with peak expression of CB1 cannabinoid receptors during sensorimotor learning. Coincident expression in a brain region essential for song learning led us to test for a potential signaling interaction. We have found that cannabinoid agonists acutely increase expression of FoxP2 throughout striatum. When administered during sensorimotor song learning, cannabinoids increase basal levels of striatal FoxP2 expression in adulthood. Thus, song-altering cannabinoid treatments are associated with persistent increases in basal expression of FoxP2 in zebra finch striatum.
Vocal learning and production in zebra finches is associated with marked physiological changes within distinct regions of telencephalon (e.g. lMAN, Area X, auditory Field L2, RA) and thalamus (DLM, ovoidalis) known to be critical for song perception, production and learning. Each of these regions distinctly and densely expresses CB1 receptors [3]. Normal development in song regions is associated with gross anatomical changes in region volume, neuron number
and density, both increases and decreases in axonal interconnections between song regions, and changes in
synaptic densities. Cannabinoid-altered vocal development implies that exogenous agonist exposure must
somehow alter some or all of these processes responsible for critical periods of song learning. We are currently
working to identify which processes are modified by developmental cannabinoid exposure and the mechanism(s) responsible.
Whereas the CA1 region appears to process features of space, the DG processes orientation in space. Both phenomena are strongly associated with the expression of LTD in these hippocampal subregions. Taken together with our findings that persistent expression of LTP occurs in the DG and CA1 regions following exposure to novel empty space, one could speculate that LTP is generated as an instantaneous response to exposure to empty space. Superimposed on this phenomenon comes the processing of novel spatial orientation through LTD in the DG and the processing of novel spatial features through LTD in the CA1 region. The integration of these individual aspects of space results in the basis for a complete spatial map of a novel environment. This implies that feature-rich spatial memory is acquired by bidirectional synaptic plasticity and that in the subregions different types of functional spatial information trigger LTD.
First, chronic unpredictable stress, used to model anhedonia, a core depression symptom, is associated with decreased endocannabinoid 2-arachidonoylglycerol in the rat hippocampus (Hill et al., 2005). Second, in humans, upregulation of PFC CB1R in suicidal depressives may indicate an adaptive response to decreased endocannabinoids (Hungund et al., 2004). Third, randomized trials of the CB1R antagonist rimonabant for obesity management increased adverse effects of depression and anxiety (Bronander and Bloch, 2007).
Cannabinoids Potentiate Emotional Learning Plasticity in Neurons of the Medial Prefrontal Cortex through Basolateral Amygdala Inputs.
Laviolette SR, Grace AA.
Departments of Neuroscience, Psychiatry, and Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
Abstract
Cannabinoids represent one of the most commonly used hallucinogenic drug classes. In addition, cannabis use is a primary risk factor for schizophrenia in susceptible individuals and can potently modulate the emotional salience of sensory stimuli. We report that systemic activation or blockade of cannabinoid CB1 receptors modulates emotional associative learning and memory formation in a subpopulation of neurons in the mammalian medial prefrontal cortex (mPFC) that receives functional input from the basolateral amygdala (BLA). Using in vivo single-unit recordings in rats, we found that a CB1 receptor agonist potentiated the response of medial prefrontal cortical neurons to olfactory cues paired previously with a footshock, whereas this associative responding was prevented by a CB1 receptor antagonist. In an olfactory fear-conditioning procedure, CB1 agonist microinfusions into the mPFC enabled behavioral responses to olfactory cues paired with normally subthreshold footshock, whereas the antagonist completely blocked emotional learning. These results are the first demonstration that cannabinoid signaling in the mPFC can modulate the magnitude of neuronal emotional learning plasticity and memory formation through functional inputs from the BLA.
Intra-dorsal periaqueductal gray administration of cannabidiol blocks panic-like response by activating 5-HT1A receptors.
Soares Vde P, Campos AC, Bortoli VC, Zangrossi H Jr, Guimarães FS, Zuardi AW.
Neuroscience and Behavioral Sciences, School of Medicine of Ribeirão Preto, Campus USP, Ribeirão Preto, SP, Brazil. vanpaso@cb.ufrn.br
Abstract
Activation of 5-HT1A receptors in the dorsal periaqueductal gray (dPAG) impairs escape behavior, suggesting a panicolytic-like effect. Cannabidiol (CBD), a major non-psychotomimetic compound present in Cannabis sativa, causes anxiolytic-like effects after intra-dPAG microinjections by activating 5-HT1A receptors. In the present work we tested the hypothesis that CBD could also impair escape responses evoked by two proposed animal models of panic: the elevated T-maze (ETM) and electric stimulation of dPAG. In experiment 1 male Wistar rats with a single cannula implanted in the dPAG received a microinjection of CBD or vehicle and, 10 min later, were submitted to the ETM and open field tests. In experiment 2 escape electrical threshold was measured in rats with chemitrodes implanted in the dPAG before and 10 min after CBD microinjection. In experiment 3 similar to experiment 2 except that the animals received a previous intra-dPAG administration of WAY-100635, a 5-HT1A receptor antagonist, before CBD treatment. In the ETM microinjection of CBD into the dPAG impaired inhibitory avoidance acquisition, an anxiolytic-like effect, and inhibited escape response, a panicolytic-like effect. The drug also increased escape electrical threshold, an effect that was prevented by WAY-100635. Together, the results suggest that CBD causes panicolytic effects in the dPAG by activating 5-HT1A receptors.
Cannabinoids promote embryonic and adult hippocampus neurogenesis and produce anxiolytic- and antidepressant-like effects.
Jiang W, Zhang Y, Xiao L, Van Cleemput J, Ji SP, Bai G, Zhang X.
Neuropsychiatry Research Unit, Department of Psychiatry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Abstract
The hippocampal dentate gyrus in the adult mammalian brain contains neural stem/progenitor cells (NS/PCs) capable of generating new neurons, i.e., neurogenesis. Most drugs of abuse examined to date decrease adult hippocampal neurogenesis, but the effects of cannabis (marijuana or cannabinoids) on hippocampal neurogenesis remain unknown. This study aimed at investigating the potential regulatory capacity of the potent synthetic cannabinoid HU210 on hippocampal neurogenesis and its possible correlation with behavioral change. We show that both embryonic and adult rat hippocampal NS/PCs are immunoreactive for CB1 cannabinoid receptors, indicating that cannabinoids could act on CB1 receptors to regulate neurogenesis. This hypothesis is supported by further findings that HU210 promotes proliferation, but not differentiation, of cultured embryonic hippocampal NS/PCs likely via a sequential activation of CB1 receptors, G(i/o) proteins, and ERK signaling. Chronic, but not acute, HU210 treatment promoted neurogenesis in the hippocampal dentate gyrus of adult rats and exerted anxiolytic- and antidepressant-like effects. X-irradiation of the hippocampus blocked both the neurogenic and behavioral effects of chronic HU210 treatment, suggesting that chronic HU210 treatment produces anxiolytic- and antidepressant-like effects likely via promotion of hippocampal neurogenesis.
Effect of cannabinoids on platelet serotonin uptake.
Velenovská M, Fisar Z.
Department of Psychiatry, 1st Faculty of Medicine, Charles University, Prague, Czech Republic.
Abstract
Serotonin is involved in many of the same processes affected by cannabinoids; therefore, we investigated in vitro and in vivo effects of these drugs on the function of serotonin transporter. The effect of Delta(9)-tetrahydrocannabinol (Delta(9)-THC), endocannabinoid anandamide and synthetic cannabinoid receptor agonist WIN 55,212-2 on platelet serotonin uptake and membrane microviscosity was examined in 19 marijuana smokers and 20 controls. (1) Serotonin uptake was inhibited at higher doses of Delta(9)-THC (IC(50) = 139 micromol/l), anandamide (IC(50) = 201 micromol/l) or WIN 55,212-2 (IC(50) = 17.4 micromol/l); the inhibition was found non-competitive. Delta(9)-THC, anandamide and WIN 55,212-2 produced different effects on the membrane microviscosity. (2) Maximal velocity of platelet serotonin uptake was significantly increased in a group of chronic marijuana smokers suffering impairment of cognitive functions when compared with controls. Opposite effect of marijuana smoking on the serotonin uptake efficiency was observed in males beside females. In summary, this study provides evidence that (1) Activity of serotonin transporter is acutely affected by cannabinoids at relatively high drug concentrations; this effect is indirect and can be partially accounted for the changes in the membrane microviscosity. (2) Increase of maximal velocity of the serotonin uptake could be understood as adaptation change in the serotonergic system induced by chronic cannabis use. A hypothesis was supported that lowered serotonin uptake may reflect a gender-related differences in effects of psychoactive cannabinoids.
Inhibition of monoamine oxidase activity by cannabinoids.
Fisar Z.
Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00, Prague 2, Czech Republic. zfisar@lf1.cuni.cz
Abstract
Brain monoamines are involved in many of the same processes affected by neuropsychiatric disorders and psychotropic drugs, including cannabinoids. This study investigated in vitro effects of cannabinoids on the activity of monoamine oxidase (MAO), the enzyme responsible for metabolism of monoamine neurotransmitters and affecting brain development and function. The effects of the phytocannabinoid Delta(9)-tetrahydrocannabinol (THC), the endocannabinoid anandamide (N-arachidonoylethanolamide [AEA]), and the synthetic cannabinoid receptor agonist WIN 55,212-2 (WIN) on the activity of MAO were measured in a crude mitochondrial fraction isolated from pig brain cortex. Monoamine oxidase activity was inhibited by the cannabinoids; however, higher half maximal inhibitory concentrations (IC(50)) of cannabinoids were required compared to the known MAO inhibitor iproniazid. The IC(50) was 24.7 micromol/l for THC, 751 micromol/l for AEA, and 17.9 micromol/l for WIN when serotonin was used as substrate (MAO-A), and 22.6 micromol/l for THC, 1,668 micromol/l for AEA, and 21.2 micromol/l for WIN when phenylethylamine was used as substrate (MAO-B). The inhibition of MAOs by THC was noncompetitive. N-Arachidonoylethanolamide was a competitive inhibitor of MAO-A and a noncompetitive inhibitor of MAO-B. WIN was a noncompetitive inhibitor of MAO-A and an uncompetitive inhibitor of MAO-B. Monoamine oxidase activity is affected by cannabinoids at relatively high drug concentrations, and this effect is inhibitory. Decrease of MAO activity may play a role in some effects of cannabinoids on serotonergic, noradrenergic, and dopaminergic neurotransmission.
Fatty acid amide hydrolase (FAAH) is an enzyme that hydrolyzes the fatty acid amide (FAA) family of endogenous signaling lipids. General classes of FAAs include the N- acylethanolamines (NAEs) and fatty acid primary amides (FAPAs). Examples of NAEs include anandamide (AEA), palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). An example of
FAPAs includes 9-Z-octadecenamide or oleamide. (McKinney MK, Cravatt BF. 2005. Annu Rev Biochem 74:411-32)].
Diseases, disorders, syndromes and/or conditions, that would benefit from inhibition of FAAH enzymatic activity include, for example, Alzheimer's Disease, schizophrenia, depression, alcoholism, addiction, suicide, Parkinson's disease, Huntington's disease, stroke, emesis, miscarriage, embryo implantation, endotoxic shock, liver cirrhosis, atherosclerosis, cancer, traumatic head injury, glaucoma, and bone cement implantation syndrome.
Other diseases, disorders, syndromes and/or conditions that would benefit from inhibition of FAAH activity, include, for example, multiple sclerosis, retinitis, amyotrophic lateral sclerosis, immunodeficiency virus-induced encephalitis, attention-deficit hyperactivity disorder, pain, nociceptive pain, neuropathic pain, inflammatory pain, non-inflammatory pain, painful hemorrhagic cystitis, obesity, hyperlipidemia, metabolic disorders, feeding and fasting, alteration of appetite, stress, memory, aging, hypertension, septic shock, cardiogenic shock, intestinal inflammation and motility, irritable bowel syndrome, colitis, diarrhea, ileitis, ischemia, cerebral ischemia, hepatic ischemia, myocardial infarction, cerebral excitotoxicity, seizures, febrile seizures, neurotoxicity, neuropathies, sleep, induction of sleep, prolongation of sleep, insomnia, and inflammatory diseases. [0028] Carbamic acid esters have shown promise as selective FAAH inhibitors (Kathuria et al., Nat. Med. 2003, 9:76-81). In particular, a series of alkylcarbamic acid aryl esters, such as, for example, the compound of Formula (I) disclosed herein, have been shown to be potent and selective inhibitors of FAAH activity. Mor et al. (J. Med. Chem. 2004, 47:4998-5008; incorporated by reference) and Piomelli et al. (International Patent Publication No. WO 2004/033422; incorporated by reference) disclosed representative alkylcarbamic acid aryl esters of Formula (I) that are potent inhibitors of FAAH activity, but do not significantly interact with selected serine hydrolases or with cannabinoid receptors. Among the disclosed alkylcarbamic acid esters of Formula (I), the compound cyclohexylcarbamic acid 3'-carbamoylbiphenyl-3-yl ester (also known as 5'- carbamoylbiphenyl-3-yl cyclohexyl carbamate, UCM597 and URB597; referenced herein as compound KDS-4103) was identified as a potent and selective inhibitor of FAAH activity.
Treatment with Delta(9)-THC did not produce significant changes in oxidative stress markers or in mRNA levels of CB1 and CB2 receptors in the liver of mice, but attenuated the increase in the selenium-dependent GPx activity (Delta(9)-THC: 8%; VCtrl: 23% increase) and the GSH/oxidized GSH ratio (Delta(9)-THC: 61%; VCtrl: 96% increase), caused by treatment with the vehicle. Delta(9)-THC administration did not show any harmful effects on lipid peroxidation, protein carboxylation or DNA oxidation in the healthy liver of mice but attenuated unexpected effects produced by the vehicle containing ethanol/cremophor EL.
Each of the 3 cannabis-associated cases of cerebellar infarction was confirmed by biopsy (1 case) or necropsy (2 cases) and showed inflammatory cellular reactions characteristic of a 1- to 3-day-old infarct (case 1) or a 3- to 7-day-old infarct (cases 2 and 3).3 In all 3 cases, the central nervous system infarction was acute and localized to cerebellum.
We previously presented a case of biopsy-proven cerebellar infarction involving multiple branch cerebellar arterial territories with a benign cerebral arteriogram in a 15-year-old male that was temporally related to heavy marijuana use, confirmed by toxicologic study. This patient presented with a 3-day history of headache, nausea, and unsteadiness of gait after a binge of marijuana smoking. Brainstem compromise caused by cerebellar and cerebral edema led to death in the 2 fatal cases. From the literature, it is clear that marijuana use can cause systemic hypotension, impair peripheral vasomotor reflexes, and may alter central nervous system blood flow and cerebral vascular autoregulation. Marijuana use has been associated with stroke in adults, but acute central nervous system infarction related to marijuana use is not well described in children. Although the mechanism of neurologic injury and its localization to the posterior circulation in these cases remains uncertain, our observation of acute cerebellar infarction in 3 adolescents shortly after marijuana use suggests that this drug may contribute to cerebellar vascular injury, possibly by causing vasospasm, especially in the inexperienced or episodic user, resulting in cerebellar ischemia.
Mice fed diets containing 3% or 6% coffee for 5 days had increased levels of mRNA for NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S-transferase class Alpha 1 (GSTA1) of between 4- and 20-fold in the liver and small intestine. Mice fed 6% coffee also had increased amounts of mRNA for UDP-glucuronosyl transferase 1A6 (UGT1A6) and the glutamate cysteine ligase catalytic (GCLC) subunit of between 3- and 10-fold in the small intestine. Up-regulation of these mRNAs was significantly greater in mice possessing Nrf2 (NF-E2 p45 subunit-related factor 2) than those lacking the transcription factor. Basal levels of mRNAs for NQO1, GSTA1, UGT1A6 and GCLC were lower in tissues from nrf2(-/-) mice than from nrf2(+/+) mice, but modest induction occurred in the mutant animals. Treatment of mouse embryonic fibroblasts (MEFs) from nrf2(+/+) mice with either coffee or the coffee-specific diterpenes cafestol and kahweol (C+K) increased NQO1 mRNA up to 9-fold. MEFs from nrf2(-/-) mice expressed less NQO1 mRNA than did wild-type MEFs, but NQO1 was induced modestly by coffee or C+K in the mutant fibroblasts. Transfection of MEFs with nqo1-luciferase reporter constructs showed that induction by C+K was mediated primarily by Nrf2 and required the presence of an antioxidant response element in the 5'-upstream region of the gene. Luciferase reporter activity did not increase following treatment of MEFs with 100 mumol/l furan, suggesting that this ring structure within C+K is insufficient for gene induction. Priming of nrf2(+/+) MEFs, but not nrf2(-/-) MEFs, with C+K conferred 2-fold resistance towards acrolein.
Epidemiological and laboratory studies have highlighted the potent chemopreventive effectiveness of both dietary selenium and cruciferous vegetables, particularly broccoli. Sulforaphane (SFN), an isothiocyanate, was identified as the major metabolite of broccoli responsible for its anti-cancer properties. An important mechanism for SFN chemoprevention is through the enhancement of glutathione (GSH), the most abundant antioxidant in animals and an important target in chemoprevention. Enhancement of GSH biosynthetic enzymes including the rate-limiting glutamate cysteine ligase (GCL), as well as other Phase II detoxification enzymes results from SFN-mediated induction of the nuclear factor-erythroid 2-related factor 2 (Nrf2)/antioxidant response elements (ARE) signaling pathway. While isothiocyanate compounds such as SFN are among the most potent Nrf2 inducers known, we hypothesized that substitution of sulfur with selenium in the isothiocyanate functional group of SFN would result in an isoselenocyanate compound (SFN-isoSe) with enhanced Nrf2 induction capability. Here we report that SFN-isoSe activated an ARE-luciferase reporter in HepG2 cells more potently than SFN. It was also found that SFN-isoSe induced GCL and GSH in MEF cells in an Nrf2-dependent manner. Finally, we provide evidence that SFN-isoSe was more effective in killing HepG2 cancer cells, yet was less toxic to non-cancer MEF cells, than SFN. These data support our hypothesis, and suggest that SFN-isoSe and potentially other isoselenocyanates may be highly effective chemoprotective agents in vivo due to their ability to induce Nrf2 with low toxicity in normal cells and high efficiency at killing cancer cells.
Oxidative stress and loss of cellular Ca2+ homeostasis are closely linked and are common denominators in the pathophysiology of many neurodegenerative diseases and acute disorders of the nervous system. Mitochondria are major targets of oxidative stress and abnormal intracellular Ca2+, as both can cause bioenergetic failure through synergistic activation of the mitochondrial inner membrane permeability transition pore. Opening of this molecularly ill-defined pore causes both collapse of the membrane potential, which drives oxidative phosphorylation, and release of small metabolites, including pyridine nucleotides and glutathione, which are necessary for energy metabolism and defense against oxidative stress. Expression of genes coding for many antioxidant defense proteins is regulated by the Nrf2 transcriptional activating factor. Translocation of this protein from the cytosol to the nucleus is stimulated by oxidative stress and by specific agents that either react with cysteine sulfhydryl groups present on the protein KEAP1, that normally binds and restricts Nrf2 translocation, or that stimulate serine phosphorylation of Nrf2. Recent evidence indicates that mitochondria are a target of the cytoprotective gene expression induced by Nrf2 and that this pathway can increase resistance to redox-regulated opening of the permeability transition pore. Pharmacologic stimulation of the Nrf2 system and its protection against mitochondrial bioenergetic dysfunction may therefore constitute a powerful mechanism for both pre-conditioning against neurodegeneration and for post-conditioning against neural cell death associated with acute neurologic injury.
Cruciferous vegetables contain glucosinolates that, after conversion to isothiocyanates (ITC), are capable of inducing cytoprotective genes. We examined whether broccoli seeds can elicit a chemoprotective response in mouse organs and rodent cell lines and investigated whether this response requires nuclear factor-erythroid 2 p45-related factor 2 (Nrf2). The seeds studied contained glucosinolate at 40 mmol/kg, of which 59% comprised glucoiberin, 19% sinigrin, 8% glucoraphanin, and 7% progoitrin. Dietary administration of broccoli seeds to nrf2(+/+) and nrf2(-/-) mice produced a approximately 1.5-fold increase in NAD(P)H:quinone oxidoreductase 1 (NQO1) and glutathione S-transferase (GST) activities in stomach, small intestine, and liver of wild-type mice but not in mutant mice; increased transferase activity was associated with elevated levels of GSTA1/2, GSTA3, and GSTM1/2 subunits. These seeds also increased significantly the level of glutamate cysteine ligase catalytic (GCLC) subunit in the stomach and the small intestine of nrf2(+/+) mice but not nrf2(-/-) mice. An aqueous broccoli seed extract was prepared for treatment of cultured cells that contained ITC at approximately 600 mumol/L, composed of 61% 3-methylsulfinylpropyl ITC, 30% sulforaphane, 4% allyl ITC, and 4% 3-butenyl ITC. This extract induced GSTA1/2, GSTA3, NQO1, and GCLC between 3-fold and 10-fold in mouse Hepa-1c1c7 and rat liver RL-34 cells. The broccoli seed extract affected increases in GSTA3, GSTM1, and NQO1 proteins in nrf2(+/+) mouse embryonic fibroblasts but not in nrf2(-/-) mouse embryonic fibroblasts. These experiments show that broccoli seeds are effective at inducing antioxidant and detoxication proteins, both in vivo and ex vivo, in an Nrf2-dependent manner.
We demonstrate that Keap1/Nrf2 and NF-kappaB respond differently to electrophiles that bind proteins covalently and the redox perturbation associated with glutathione depletion, and that crosstalk may enable NF-kappaB to partly influence Nrf2 expression during cellular stress. We have investigated two transcription factors known to be sensitive to electrophilic stress and redox perturbation, Nrf2 and NF-kappaB, in mouse liver cells. Cellular stress was induced by the probes: N-acetyl-p-benzoquinineimine (NAPQI), the reactive metabolite of acetaminophen; dinitrochlorobenzene (DNCB), a model electrophile; and buthionine (S,R)-sulfoximine (BSO), an inhibitor of glutamate-cysteine ligase. NAPQI, DNCB and BSO can all cause glutathione (GSH) depletion; however only NAPQI and DNCB can covalently bind proteins.
Northern blotting has shown that mouse small intestine contains relatively large amounts of the nuclear factor-E2 p45-related factor (Nrf) 2 transcription factor but relatively little Nrf1. Regulation of intestinal antioxidant and detoxication enzymes by Nrf2 has been assessed using a mouse line bearing a targeted disruption of the gene encoding this factor. Both Nrf2-/- and Nrf2+/+ mice were fed a control diet or one supplemented with either synthetic cancer chemopreventive agents [butylated hydroxyanisole (BHA), ethoxyquin (EQ), or oltipraz] or phytochemicals [indole-3-carbinol, cafestol and kahweol palmitate, sulforaphane, coumarin (CMRN), or alpha-angelicalactone]. The constitutive level of NAD(P)H:quinone oxidoreductase (NQO) and glutathione S-transferase (GST) enzyme activities in cytosols from small intestine was typically found to be between 30% and 70% lower in samples prepared from Nrf2 mutant mice fed a control diet than in equivalent samples from Nrf2+/+ mice. Most of the chemopreventive agents included in this study induced NQO and GST enzyme activities in the small intestine of Nrf2+/+ mice. Increases of between 2.7- and 6.2-fold were observed in wild-type animals fed diets supplemented with BHA or EQ; increases of about 2-fold were observed with a mixture of cafestol and kahweol palmitate, CMRN, or alpha-angelicalactone; and increases of 1.5-fold were measured with sulforaphane. Immunoblotting confirmed that in the small intestine, the constitutive level of NQO1 is lower in the Nrf2-/- mouse, and it also showed that induction of the oxidoreductase was substantially diminished in the mutant mouse. Immunoblotting class-alpha and class-mu GST showed that constitutive expression of most transferase subunits is also reduced in the small intestine of Nrf2 mutant mice. Significantly, induction of class-alpha and class-mu GST by EQ, BHA, or CMRN is apparent in the gene knockout animal. No consistent change in the constitutive levels of the catalytic heavy subunit of gamma-glutamylcysteinyl synthetase (GCS(h)) was observed in the small intestine of Nrf2-/- mice. However, although the expression of GCS(h) was found to be increased dramatically in the small intestine of Nrf2+/+ mice by dietary BHA or EQ, this induction was essentially abolished in the knockout mice. It is apparent that Nrf2 influences both constitutive and inducible expression of intestinal antioxidant and detoxication proteins in a gene-specific fashion. Immunohistochemistry revealed that induction of NQO1, class-alpha GST, and GCS(h) occurs primarily in epithelial cells of the small intestine. This suggests that the variation in inducibility of NQO1, Gsta1/2, and GCS(h) in the mutant mouse is not attributable to the expression of the enzymes in distinct cell types but rather to differences in the dependency of these genes on Nrf2 for induction.
tert-Butyl-4-hydroxyanisole (BHA) and its demethylated analog, tert-butyl-hydroquinone (TBHQ), are antioxidants used in food. Both BHA and TBHQ have been shown to promote kidney and bladder carcinogenesis in the rat. We have previously demonstrated that glutathione (GSH) conjugates of a variety of hydroquinones are nephrotoxic and proposed that GSH conjugation serves to target these compounds to the kidney. In the present study, we examined the metabolism of TBHQ, focusing on the formation of potentially nephrotoxic sulfur-containing metabolites. 2-tert-Butyl-5-glutathion-S-ylhydroquinone, 2-tert-butyl-6-glutathion-S-ylhydroquinone, and 2-tert-butyl-3,6-bisglutathion-S-ylhydroquinone were identified as biliary metabolites of TBHQ (1.0 mmol/kg, ip) in male F344 rats, accounting for 2.2% of the dose. Liquid chromatography/mass spectroscopic analysis of urine also revealed the presence of additional sulfur-containing metabolites, tentatively identified as 2,5-dihydroxy-3-tert-butyl-thiophenol, 2,5-dihydroxy-4-tert-butylthiophenol, and their S-methyl derivatives. No mercapturic acids of TBHQ were found in the urine. The major biliary and urinary metabolites were TBHQ-glucuronide and TBHQ-sulfate, with a trace of TBHQ excreted unchanged. The results indicate that TBHQ undergoes oxidation and GSH conjugation in vivo in the male F344 rat. These conjugates are excreted into bile and undergo further metabolism prior to excretion in urine. Formation of the S-containing metabolites of TBHQ may occur in amounts sufficient to play a role in the toxicity of TBHQ to kidney and bladder.
Effects of the dietary antioxidants alpha-tocopherol (alpha-Toc), t-butylhydroquinone (TBHQ), propyl gallate (PG) and butylated hydroxytoluene (BHT) were examined using a multi-organ carcinogenesis model. Groups of 20 F344 male rats were treated with a single intragastric administration of 100 mg/kg body weight N-methyl-N'-nitro-N-nitrosoguanidine, a single intragastric administration of 750 mg/kg body weight N-ethyl-N-hydroxyethylnitrosamine, two subcutaneous injections of 0.5 mg/kg body weight N-methylbenzyl-nitrosamine and four subcutaneous injections of 40 mg/kg body weight 1,2-dimethylhydrazine. At the same time the rats were given 0.1% N-dibutylnitrosamine for 4 weeks and then 0.1% 2,2'-dihydroxy-di-n-propylnitrosamine for 2 weeks in the drinking water, for a total carcinogen exposure period of 6 weeks. Starting 3 days thereafter the rats received 1% alpha-Toc, 1% TBHQ, 1% PG or 0.7% BHT in the diet, or basal diet alone. Further groups of 10-15 animals each were treated with antioxidant alone or basal diet alone as controls. Surviving animals were killed at the end of week 36. Histopathological examination showed that alpha-Toc increased the incidence of glandular stomach atypical foci but reduced the incidence and multiplicity of kidney atypical tubules. TBHQ significantly elevated the incidences of esophageal papillary or nodular (PN) hyperplasias and papillomas, as well as forestomach papillomas, but significantly decreased the multiplicity of colon adenocarcinomas. PG was only effective in reducing the multiplicity of kidney atypical tubules. BHT enhanced the development of thyroid hyperplasias, but strongly reduced the incidence and multiplicity of colon adenocarcinomas. This compound was also associated with lowered incidence and multiplicity of renal cell tumors. None of the agents studied was unequivocal in exerting either positive or negative influence.
To determine whether the disruption of thyroid hormone and retinoid homeostasis that occurs after exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can be mediated by the arylhydrocarbon receptor (AhR), pregnant AhR-heterozygous (AhR+/-) mice were administered a single oral dose of 10 microg kg(-1) TCDD at gestation day 12.5. Serum and liver were collected on postnatal day 21 from vehicle-treated control or TCDD-treated AhR+/- and AhR-null (AhR-/-) mouse pups. Whereas TCDD exposure resulted in a marked reduction of total thyroxin (TT4) and free T4 (FT4) levels in the serum of AhR+/- mice, TCDD had no effects on AhR-/- mice. Gene expression of UDP-glucuronosyltransferase (UGT)1A6, cytochrome P450 (CYP)1A1, and CYP1A2 in the liver was induced markedly by TCDD in AhR+/- but not AhR-/- mice. Induction of CYP1A1 in response to TCDD was confirmed by immunohistochemical evidence in that CYP1A1 protein was conspicuously localized in the cytoplasm of hepatocytes in the centrilobular region. Levels of retinyl palmitate were greatly reduced in the liver of TCDD-exposed AhR+/- mice, but not in vehicle-treated AhR+/- mice. No effects of TCDD on retinoid levels in the liver were found in AhR-/- mice. We conclude that disruption of thyroid hormone and retinoid homeostasis is mediated entirely via AhR. Induction of UGT1A6 is thought to be responsible at least partly for reduced serum thyroid hormone levels in TCDD-exposed mice.
The aryl hydrocarbon receptor (AHR) plays a central role in 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin) hepatotoxicity, regulation of xenobiotic metabolism, and hepatovascular development. Each of these processes appears to be dependent on binding of the AHR to dioxin- responsive elements (DREs) within the genome. The Cyp1a1 and Cyp1a2 loci represent linked genes thought to play important roles in AHR biology. In the mouse, 8 DREs are located in the 14-kb intergenic region between the Cyp1a1 and Cyp1a2 genes. Seven of these DREs, collectively known as the DRE cluster (DREC), are located 1.4 kb upstream of the Cyp1a1 transcriptional start site and 12.6 kb upstream of the Cyp1a2 start site. To investigate the role of the DREC in each aspect of AHR biology, we generated a DREC-deficient mouse model through homologous recombination. Using this mouse model, we demonstrate that the DREC controls the adaptive up-regulation of both Cyp1a1 and Cyp1a2 genes in vivo. Using selected aspects of acute hepatic injury as endpoints, we also demonstrate that DREC null mice are more sensitive to dioxin-induced hepatotoxicity than WT mice. The results of parallel toxicologic studies using individual Cyp1a1 and Cyp1a2 null mice support the observation that up-regulation of these P450s is not the cause of many aspects of dioxin hepatotoxicity. Finally, we observed normal closure of the ductus venosus (DV) in DREC null mice. Given the 100% penetrance of patent DV in Ahr null mice, these results indicate that Cyp1a1 and Cyp1a2 do not play a dominant role in AHR-mediated vascular development.
We report the first genome-wide association study of habitual caffeine intake. We included 47,341 individuals of European descent based on five population-based studies within the United States. In a meta-analysis adjusted for age, sex, smoking, and eigenvectors of population variation, two loci achieved genome-wide significance: 7p21 (P = 2.4×10(-19)), near AHR, and 15q24 (P = 5.2×10(-14)), between CYP1A1 and CYP1A2. Both the AHR and CYP1A2 genes are biologically plausible candidates as CYP1A2 metabolizes caffeine and AHR regulates CYP1A2.
Inflammatory signaling plays a key role in tumor progression, and the pleiotropic cytokine interleukin-6 (IL-6) is an important mediator of protumorigenic properties. Activation of the aryl hydrocarbon receptor (AHR) with exogenous ligands coupled with inflammatory signals can lead to synergistic induction of IL6 expression in tumor cells. Whether there are endogenous AHR ligands that can mediate IL6 production remains to be established. The indoleamine-2,3-dioxygenase pathway is a tryptophan oxidation pathway that is involved in controlling immune tolerance, which also aids in tumor escape. We screened the metabolites of this pathway for their ability to activate the AHR; results revealed that kynurenic acid (KA) is an efficient agonist for the human AHR. Structure-activity studies further indicate that the carboxylic acid group is required for significant agonist activity. KA is capable of inducing CYP1A1 messenger RNA levels in HepG2 cells and inducing CYP1A-mediated metabolism in primary human hepatocytes. In a human dioxin response element-driven stable reporter cell line, the EC(25) was observed to be 104nM, while in a mouse stable reporter cell line, the EC(25) was 10muM. AHR ligand competition binding assays revealed that KA is a ligand for the AHR. Treatment of MCF-7 cells with interleukin-1beta and a physiologically relevant concentration of KA (e.g., 100nM) leads to induction of IL6 expression that is largely dependent on AHR expression. Our findings have established that KA is a potent AHR endogenous ligand that can induce IL6 production and xenobiotic metabolism in cells at physiologically relevant concentrations.
Maltol is used extensively as a flavor-enhancing agent, food preservative, antioxidant, and also in cosmetic and pharmaceutical formulations. However, a number of studies have shown that maltol may induce carcinogenicity and toxicity but the mechanisms involved remain unknown. Therefore, we examined the ability of maltol to induce the cytochrome P450 1a1 (Cyp1a1), an enzyme known to play an important role in the chemical activation of xenobiotics to carcinogenic derivatives. Our results showed that treatment of Hepa 1c1c7 cells with maltol significantly induced Cyp1a1 at mRNA, protein, and activity levels in a concentration-dependent manner. The RNA synthesis inhibitor, actinomycin D, completely blocked the Cyp1a1 mRNA induction by maltol, indicating a requirement of de novo RNA synthesis through transcriptional activation. In addition, maltol induced aryl hydrocarbon receptor (AhR)-dependent luciferase reporter gene expression in stably transfected H1L1.1c2 cells, suggesting an AhR-dependent mechanism. This is the first demonstration that the food flavoring agent, maltol, can directly induce Cyp1a1 gene expression in an AhR-dependent manner and represents a novel mechanism by which maltol promotes carcinogenicity and toxicity.
BACKGROUND AND PURPOSE: There is a strong correlation between cytochrome P450 (P450)-dependent arachidonic acid metabolism and the pathogenesis of cardiac hypertrophy. Several aryl hydrocarbon receptor (AhR) ligands were found to alter P450-dependent arachidonic acid metabolism. Here, we have investigated the effect of 3-methylcholanthrene (3-MC) and benzo(a)pyrene (BaP), two AhR ligands, on the development of cardiac hypertrophy.
EXPERIMENTAL APPROACH: Male Sprague Dawley rats were injected (i.p.) daily with either 3-MC (10 mg kg(-1)) or BaP (20 mg kg(-1)) for 7 days. Then hearts were removed, and the heart to body weight ratio and the gene expression of the hypertrophic markers and P450 genes were determined. Levels of arachidonic acid metabolites were determined by liquid chromatography-electron spray ionization-mass spectrometry.
KEY RESULTS: Both 3-MC and BaP increased the heart to body weight ratio as well as the hypertrophic markers, atrial natriuretic peptide and brain natriuretic peptide. 3-MC and BaP treatment increased the gene expression of CYP1A1, CYP1B1, CYP2E1, CYP4F4, CYP4F5 and soluble epoxide hydrolase. Both 3-MC and BaP treatments increased the dihydroxyeicosatrienoic acids (DHETs) : epoxyeicosatrienoic acids (EETs) ratio and the 20-hydroxyeicosatetraenoic acid (20-HETE) : total EETs ratio. Treatment with benzo(e)pyrene, an isomer of BaP that is a poor ligand for the AhR, did not induce cardiac hypertrophy in rats, confirming the role of AhR in the development of cardiac hypertrophy. Treatment with the omega-hydroxylase inhibitor, HET0016, significantly reversed BaP-induced cardiac hypertrophy.
CONCLUSIONS AND IMPLICATIONS: 3-MC and BaP induce cardiac hypertrophy by increasing the ratio of DHETs : EETs and/or the ratio of 20-HETE : total EETs, through increasing soluble epoxide hydrolase activity.
Among all food additive-containing foods, the highest contributors were: soft drinks to benzoates intake, nuts and canned juices to sulphites intake, bread and biscuits to BHA intake and chewing gum to BHT intake.
We examined the food additive, butylated hydroxyanisole (BHA), for its capacity to modulate the cytotoxic effects of Δ9-tetrahydrocannabinol (THC). THC was not cytotoxic when added to cultures of A549 lung tumor cells at concentrations<5 μg/ml, but induced cell necrosis at higher levels with an LC50=16–18 μg/ml. BHA alone, at concentrations of 10–200 μM, produced limited cell toxicity but significantly enhanced the necrotic death resulting from concurrent exposure to THC. In the presence of BHA at 200 μM, the LC50 for THC decreased to 10–12 μg/ml. Similar results were obtained with smoke extracts prepared from marijuana cigarettes, but not with extracts from tobacco or placebo marijuana cigarettes (containing no THC). Two different mechanisms for this synergistic cytotoxicity were investigated. Experiments were repeated in the presence of either diphenyleneiodonium or dicumarol as inhibitors of the redox cycling pathway. Neither of these compounds protected cells from the effects of combined THC and BHA, but rather enhanced necrotic cell death. Measurements of cellular ATP revealed that both THC and BHA reduced ATP levels in A549 cells, consistent with toxic effects on mitochondrial electron transport. The combination was synergistic in this respect, reducing ATP levels to <15% of control. Exposure to marijuana smoke in conjunction with BHA, a common food additive, may promote deleterious health effects in the lung.
The effects of butylated hydroxyanisole (BHA), a commonly used food antioxidant, on oxygen consumption, ATPase activity, and the redox state of some electron carriers of rat liver mitochondria have been studied. It was observed that BHA slightly stimulated state 4 respiration but strongly inhibited ADP- and uncoupler-stimulated respiration on NAD+- and FAD-linked substrates. ATPase activity and vectorial H+ ejection were affected only slightly by BHA, suggesting that BHA predominantly inhibits mitochondrial electron flow. Experiments to determine its site of action showed that BHA did not noticeably affect electron flow through cytochrome oxidase; in contrast, NADH:duroquinone reductase activity and electron flow through ubiquinone-cytochrome b-cytochromec complex were inhibited strongly because the oxidation of duroquinol was affected markedly. The BHA block of electron transport was bypassed by both N,N,N′,N′-tettamethyl-p-phenyleaediamine and 2,6-dichlorophenolindophenol. Also, the presence of BHA changed the redox state of cytochrome b and C1 to a more oxidized level. These observations suggest that electron transport is inhibited by BHA at the NADH-ubiquinone and at the ubiquinone-cytochrome b levels. From Hill plots, it is clear that more than one binding site is involved in complete inhibition; in addition, available evidence suggests that there may be two sites at the substrate side of ubiquinone and another two sites at the oxygen side of ubiquinone. Consequently, mitochondrial ATP synthesis would be interrupted. This event could be related to the toxicity of BHA.
Exposure to marijuana smoke in conjunction with BHA, a common food additive, may promote deleterious health effects in the lung." BHA & BHT are human-made fat preservatives, and are found in many packaged foods including: plastics in boxed cereal, Jello, Slim Jims, and more
BHA is added to butter, lard, meats, cereals, baked goods, sweets, beer, vegetable oils, potato chips, snack foods, nuts and nut products, dehydrated potatoes, and flavoring agents. It is used in sausage, poultry and meat products, dry mixes for beverages and desserts, glazed fruits, chewing gum, active dry yeast, defoaming agents for beet sugar and yeast, and emulsion stabilizers for shortenings.
BHA stabilizes the petroleum wax coatings of food packaging (Sax and Lewis 1987). BHA is considered a GRAS (generally recognized as safe) compound by the FDA when the content of the antioxidant is not greater than 0.02% w/w of the total fat or oil content of the food.
Fast food service personnel who normally cook and serve fried and oily foods have the potential for high exposure to BHA. Potential occupational exposure exists for workers in certain industries, including food producers, animal feed producers, livestock producers, cosmetic manufacturers, some petroleum workers, and rubber producers and those who handle the end products such as tires.
BHA is used as a preservative and antioxidant in pharmaceutical preparations and cosmetic formulations containing fats and oils (Osol 1980). Cosmetic-grade BHA reportedly contains a minimum of 90% 3-BHA and approximately 8% 2-BHA (IARC 1986). In a 1981 FDA survey, BHA was reported to be used in 3,217 to 21,279 cosmetic formulations; the majority (88%) of the reported concentrations was ≤0.1% (IARC 1986). One product, a lipstick, was reported to contain >10% BHA. In this survey, lipstick formulations (1,256 products) represented the highest use of BHA, with eye shadows being the next highest (410 products). A widely used antioxidant mixture for cosmetics contained 20% BHA, 6% propyl gallate, 4% citric acid, and 70% propylene glycol (Kirk-Othmer 1979a, IARC 1986).
Potential for consumer exposure to BHA by ingestion and dermal contact is widespread. In 1975, the estimated average daily intake of BHA in the diet was 4.3 mg (IARC 1986). It is a widely used food additive in products containing vegetable oils or animal fats. It retains its antioxidant properties even at high temperatures. The general population may be exposed to BHA in butter, lard, meats, cereals, baked goods, sweets, beer, vegetable oils, potato chips, snack foods, nuts, dehydrated potatoes, flavoring agents, sausage, poultry and meat products, dry mixes for beverages and desserts, glazed fruits, chewing gum, active dry yeast, defoaming agents for beet sugar and yeast, and emulsion stabilizers for shortenings. The estimated U.S. consumption of BHA in food increased to 660,000 lb/yr during 1970 to 1982, up from 374 lb/yr in 1960 (Anonymous 1984, IARC 1986). Reported annual consumption for BHA in the mid 1970s was 990,000 lb compared with 3.1 million lb for butylated hydroxytoluene (BHT) (Kirk-Othmer 1978). Industrial use of BHA has largely been replaced by tert-butylhydroquinone (TBHQ) (Kirk-Othmer 1980).
In addition, the aryl hydrocarbon receptor (AHR) antagonist, resveratrol, inhibited the increase in Cyp1a1 activity by tBHQ.
In contrast to the beneficial effects of tert-butylhydroquinone (tBHQ) as a food antioxidant, a number of studies have shown that chronic exposure to tBHQ may induce carcinogenicity. Therefore, we examined the ability of tBHQ to induce the cytochrome P450 1a1 (Cyp1a1), an enzyme known to play an important role in the chemical activation of xenobiotics to carcinogenic derivatives. A significant concentration-dependent increase in Cyp1a1 mRNA, protein, and activity occurred after treatment of murine hepatoma Hepa 1c1c7 cells with tBHQ. The increase in mRNA was apparent 3 h after treatment. The RNA polymerase inhibitor, actinomycin D, completely blocked the Cyp1a1 induction by tBHQ, indicating a requirement of de novo RNA synthesis through transcriptional activation. The protein synthesis inhibitor cycloheximide superinduced the tBHQ-mediated induction of Cyp1a1 mRNA and completely prevented the increase in Cyp1a1 activity, indicating that the induction of enzyme activity by tBHQ is dependent on de novo protein synthesis. In addition, the aryl hydrocarbon receptor (AHR) antagonist, resveratrol, inhibited the increase in Cyp1a1 activity by tBHQ. Gel electrophoretic mobility shift assays showed that tBHQ causes activation or transformation of the AHR in nuclear extracts, indicating that AHR-dependent mechanisms contributed to the Cyp1a1 induction. Similar to murine Hepa 1c1c7 cells, tBHQ caused a concentration-dependent increase in CYP1A1 at the mRNA and activity levels in human HepG2 cells. This is the first demonstration that the phenolic antioxidant, tBHQ, can directly induce Cyp1a1 gene expression in an AHR-dependent manner and may represent a novel mechanism by which tBHQ promotes carcinogenicity.
We recently demonstrated that heavy metals, Hg2+, Pb2+, and Cu2+ induced Cyp1a1 gene expression, yet the mechanisms involved remain unknown. To explore the molecular mechanisms involved in the modulation of Cyp1a1 by heavy metals, Hepa 1c1c7 cells were treated with the metals in the presence and absence of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), a potent Cyp1a1 inducer. Time-dependent effect study showed that all metals significantly induced the basal Cyp1a1 mRNA. This was apparent 3 h after treatment, and levels remained elevated for at least 24 h. At the inducible level, Hg2+ and Pb2+ further increased, while Cu2+ decreased, the TCDD-mediated induction of Cyp1a1 mRNA. The RNA synthesis inhibitor, actinomycin D, completely blocked the Cyp1a1 induction by heavy metals. The protein synthesis inhibitor, cycloheximide, and 26S proteasome inhibitor, carbobenzoxy-L-leucyl-L-leucyl-leucinal (MG-132), superinduced the metal-mediated induction of Cyp1a1 mRNA. In addition, all three metals induced aryl hydrocarbon receptor/xenobiotic-responsive element (AhR/XRE) binding, suggesting an AhR-dependent mechanism. Cyp1a1 mRNA and protein decay experiments showed that the three metals did not significantly affect the half-life of mRNA; however, they significantly decreased the degradation rate of its protein, implying a posttranslational regulation of the Cyp1a1 by the heavy metals. A significant decrease in TCDD-mediated induction of Cyp1a1 activity associated with an increase in HO-1 mRNA and a decrease in cellular heme content was observed after all metals treatment. This suggests that heme degradation plays a role in reducing Cyp1a1 activity. This is the first demonstration that heavy metals can directly induce Cyp1a1 gene expression in an AhR-dependent manner through transcriptional and posttranslational mechanisms.
Oxidation of catechols to semiquinones and quinones is a mechanism of tumor initiation, not only for endogenous estrogens, but also for synthetic estrogens such as DES and BPA, a human carcinogen, because quinone reacts with DNA [15]
Recently, alkylphenols such as p-octylphenol (p-OP), p-nonylphenol (p-NP), and bisphenol A (2,2-bis(4-hydroxyphenyl)propane, BPA) have been recognized as endocrine-disrupting chemicals to interfere with hormones of animals as well as phthalic esters and styrene.
Among alkylphenols, BPA is widely used as a material for polycarbonate resins and epoxy resins,
and it may contaminate food from the inner coating of the can and migrate from polycarbonate tableware and plastic packaging.
Chemical and biological degradation of BPA have been reported by several researchers. Horikoshi et al. reported that nonylphenol polyethoxylate was photodegraded in the presence of titanium dioxide. Nonylphenol ethoxylate was oxidized by ozone and hydrogen peroxide.
On the other hand, there are many reports for biologically degrading and polymerizing alkylphenols such as BPA using microorganisms and enzyme
Ronen and Abeliovich observed microbial degradation of BPA and tribromophenol by sediments. Lobos et al. reported that Gram-negative aerobic bacteria could degrade BPA and its analogues. Furusawa et al. also found microorganisms which could degrade p-NP.
cytochrome c oxidase subunit II, GRB2-associated binding protein 2, adaptor-related protein complex 2, and guanine nucleotide exchange factor p532
A Novel Rodent Model of Autism: Intraventricular Infusions of Propionic Acid Increase Locomotor Activity and Induce Neuroinflammation and Oxidative Stress in Discrete Regions of Adult Rat Brain http://www.autismcanada.org/pdfs/ajbb.pdf
Propionic acid is commonly used as a food preservative in wheat and dairy food products and may be involved in the recent postulated increase in the incidence of autistic spectrum disorder cases in North America (approximately 1 in 166). A number of effects have been shown following PPA treatment, including catecholamine and proenkephalin gene induction[46], cytoskeletal phosphorylation[47], histone modulation[48], second messenger metabolism[49], impaired mitochondrial respiratory transport chain function[50,51], modulation of gap junctions[52] and immune system activation[53]. There is also evidence of variable PPA metabolism in a number of metabolic disorders such as propionic and methylmalonic acidemia[54], disorders of biotin[55] and B12 metabolism[56], as well as following valproate[57] and ethanol exposure[58]. These disorders are associated with developmental delay, seizure and episodes of paroxysmal metabolic dysfunction resulting in increased oxidative stress and are to some degree reminiscent of autism[59,60]. We have hypothesized that PPA may be a candidate environmental factor putatively involved in the diverse behavioral, neuropathological and gastrointestinal aspects of ASD[61]. In our initial studies we found that repeated microinfusions of PPA into the lateral cerebral ventricles of adult rats produced behavioral, electrophysiological and neuropathological effects consistent with ASD[61]. PPA treated animals exhibited increased locomotor activity and repetitive behaviors such as dystonic limb movements, retropulsion and axial hyperextension. Simultaneous electrophysiological examination of cortical, hippocampal and striatal EEG evidenced electrographic changes reminiscent of human complex partial seizure and movement disorder. These effects were apparent within minutes of microinfusion. Furthermore, repeated exposures resulted in increased behavioral and electrographic effects suggestive of a kindling process. Collectively these findings indicated that PPA may have permanent effects on brain function. Neuropathological analysis of hippocampus and external capsule white matter tissue revealed PPA related increases in reactive astrocytes and activated microglia in the absence of gross neuronal loss and apoptotic effects. Additional analyses of whole brain homogenates produced evidence of increased oxidative stress and impaired glutathione metabolism in PPA treated animals. These findings are consistent with the neuropathological changes found in ASD autopsy brains[8] as well as biochemical studies in ASD patients[27,31]. The present study extended the examination of the effects of intraventricular PPA infusion on behavior, neuropathology and oxidative stress levels in the adult rodent ASD model. In particular, we characterized PPA induced increases in locomotor activity with additional automated measures of horizontal and vertical activity. We also examined the neuropathological responses following the twice-daily treatment schedule, utilizing additional indices of microglial activation and neurotoxicity. Lastly, we examined pro- and antioxidative stress pathways in brain regions which have been previously implicated in ASD pathophysiology.
Propionic acid is also used as an inert ingredient in pesticide formulations.
Propionic acid (PPA) is a dietary and gut bacterial short chain fatty acid which can produce brain and behavioral changes reminiscent of ASD following intraventricular infusion in rats. Impairments in GSH and catalase levels may render CNS cells more susceptible to oxidative stress from a variety of toxic insults.
THC-induced working memory deficits in a delayed alternation T-maze task are associated with altered dopamine and noradrenaline turnover in the rat prefrontal cortex.
Rats must shift attentional bias (or ‘set’) between different abstract features of stimuli, a process
termed ‘attentional set shifting’. In contrast, in order to perform reversal-learning discriminations, rats must update contingencies between stimuli and reward presentation when these are reversed. Acute administration of D9-THC impairs performance on reversal learning stages of the task, whilst attentional set shifting ability is unaffected.
Initial evidence that antagonism of CB1 receptors may improve certain memory processes was obtained using an olfactory recognition task. As mature rodents normally spend more time investigating unfamiliar than familiar conspecific animals, the olfactory recognition task measures social short-term working memory capacity. In this task, administration of SR141716A alone improves olfactory recognition memory in both aged rats and mice. In addition, SR141716A improves working memory performance on the 8-arm radial maze when long delay periods are included. These studies have therefore, suggested that SR141716A may exert nootropic effects when administered alone, and, by extension, indicate that the endocannabinoid system may negatively influence some mnemonic processes.
Introduction
The cannabinoid CB1 receptor antagonist, rimonabant, has been marketed since August 2006 in several EU countries under the commercial name of Acomplia as a pharmacological aid to exercise and calorie-intake reduction for the treatment of obesity and its metabolic complications, such as dyslipidemia and glucose intolerance [1]. About a year earlier, Sativex, a pharmaceutical preparation based on extracts of Cannabis sativa, and containing the psychotropic cannabinoid Δ9-tetrahydrocannabinol (THC) together with the nonpsychotropic cannabidiol (Figure 1) in an 1:1 ratio, was introduced in Canada for the treatment of neuropathic pain associated with multiple sclerosis [2]. These recent milestones of the exploitation of the plant with perhaps the oldest history of medicinal and recreational use by mankind are the result of four decades of intensive research. This process started with the identification and chemical synthesis of THC, the controlled study of its pharmacological properties, and the identification of its receptors in animal organisms and of their endogenous ligands, the endocannabinoids (Figure 1), and it continued with the progressive understanding of the physiological and pathological roles of this newly discovered signaling system and the appreciation of the potential therapeutic use not only of THC and endocannabinoids, but also of other plant cannabinoids. Despite this impressive sequence of achievements, whose aspects have been the subject of recent “historical” reviews [3], [4] and [5], there is much more to the original understanding of the THC mechanism of action than the discovery of the endocannabinoid system. The purpose of this article is not merely to highlight the past contribution of chemical biology to our current understanding of endocannabinoid regulation and function, but, more importantly, to discuss the several other discoveries that stemmed, and are still likely to originate in the future, from the finding of cannabinoid receptors and their endogenous ligands.
Figure 1. Chemical Structures of the Most-Studied Endocannabinoids, of a Cannabinoid Receptor Antagonist, and of Some Plant Cannabinoids
Chemical structures of (1) the two best-studied endocannabinoids, anandamide and 2-arachidonoyl glycerol [7], [8] and [9]; (2) the CB1 receptor antagonist/inverse agonist rimonabant, now on the market under the trade name Acomplia, as a pharmacological aid for the therapy of obesity and the metabolic syndrome [1]; (3) the two major plant cannabinoids, the psychotropic Δ9-THC and the nonpsychoactive cannabidiol, which are also the major constituents, in a 1:1 ratio, of Sativex, currently marketed in Canada against neuropathic pain in patients with multiple sclerosis [2].
From Plant Chemicals to Chemical Signals: Are Endocannabinoids Just Like Endorphins?
Thanks to the chemical synthesis of enantiomerically pure THC analogs (Figure 1), it became clear that the pharmacological actions of this compound were not merely due to its capability to alter membrane permeability in a nonspecific way, but rather to the interaction with specific binding sites. The same analogs, once chemically modified and radiolabelled, served as a tool for the identification of these “cannabinoid” receptors in the rat brain [6]. The finding of the first cannabinoid receptor, the CB1, out of a series of previously cloned orphan G protein-coupled receptors (GPCRs), soon to be followed by the homology cloning of the second type of cannabinoid receptors, the CB2, marked the beginning of the discovery of the endogenous cannabinoid signaling system and prompted the search for endogenous ligands, much in the same way as the identification of receptors for another plant natural product, morphine, had led to the identification of the endorphins two decades earlier. This search, however, might have lasted for several years had it not been guided by a chemical concept, i.e., that, by homology to the highly lipophilic THC, physiological cannabinoid receptor ligands were to be looked for among endogenous lipids rather than peptides like the endorphins. This idea was also supported by the observation that CB1 receptors exhibit relatively high homology with the GPCRs for another family of lipid signals, the lysophosphatidic acids. The identification of the fatty acid ethanolamide anandamide (N-arachidonoylethanolamide) [7] and of its glycerol ester analog, 2-arachidonoyl-glycerol (2-AG) [8] and [9], as endogenous agonists of CB1 and CB2 receptors (Figure 1), and the subsequent finding of their metabolic pathways and enzymes (see [10] for an updated review; see Figure S1 in the Supplemental Data available with this article online), provided the basis for the study of the physiological and pathological role of this endogenous signaling apparatus.
Beyond the similar history of their discoveries, the commonalities between opioid and cannabinoid receptors have been known even before the discovery of the latter, and they include similar inhibitory actions on nociception, gastrointestinal and cardiovascular function, anxiety and stress, and facilitatory actions on food intake and reward in laboratory animals (see [11], [12] and [13] for recent reviews; Table S1). The coupling, via inhibitory Gi/o proteins, of these two receptors to similar intracellular signaling pathways [14] underlies, to some extent, these similarities, whereas interactions between these pathways [13] probably explain why antagonists of each receptor type sometimes counteract the pharmacological effects induced by the stimulation of the other. However, one should not get the impression that the endocannabinoid system is a mere functional duplication of opioidergic signaling. The emerging scenario, in fact, distinguishes between the general strategies of endocannabinoid and endogenous opioid signaling based on the fact that, unlike endorphins, anandamide and 2-AG are lipophilic compounds produced from membrane phosphoglycerides via Ca2+-sensitive biosynthetic pathways triggered on demand, rather than being prestored in secretory vesicles. Hence, because of their chemical nature, endocannabinoids do not typically function like hormones, but they instead act as local (autocrine or paracrine) mediators. This is clearly the case with endocannabinoid action in the brain, where the elevation of intracellular Ca2+ caused by postsynaptic neuron depolarization or stimulation of postsynaptic neurotransmitter receptors coupled to Ca2+ mobilization from intracellular stores, or both, stimulates enzymes catalyzing the biosynthesis of anandamide and, particularly, 2-AG. These compounds are then released from the neuron to activate presynaptic CB1 receptors that, in most cases via inhibition of voltage-activated calcium channels, reduce the release of both excitatory (e.g., glutamate) and inhibitory (e.g., GABA) neurotransmitters, thereby producing various effects on neuronal synapses [15]. This “retrograde” mode for endocannabinoid action (Figure S1) has been implicated in several physiopathological functions of the brain, including the control of food intake, habit-forming and mnemonic processes, neuronal plasticity, and excitotoxicity. Since the biosynthetic precursors for endocannabinoids seem to be ubiquitous in membranes, it is the reciprocal pattern of expression of endocannabinoid biosynthesising enzymes and cannabinoid receptors that determines the specificity of endocannabinoid action, whereas the localization of the degrading enzymes sets its duration. Indeed, the sn-1-specific diacylglycerol lipase (DAGL)-α catalyzing 2-AG release from diacylglycerols [16] is expressed in postsynaptic dendritic “spines” that make synapses with axon terminals expressing CB1 receptors [17] and [18]. This allows a lipophilic molecule like 2-AG to reach its target in close proximity to its site of biosynthesis. Also, one of the enzymes responsible for 2-AG degradation, the monoacylglycerol lipase (MAGL), is located in presynaptic neurons, thus allowing for the immediate inactivation of the endocannabinoid signal [19]. Elegant experiments established the time and space frames for endocannabinoid retrograde action [20] and [21], which can distinguish between neighboring CB1-expressing glutamate- and GABA-releasing neurons as targets [22] and [23]. The type and time coincidence of Ca2+-mobilizing stimuli play a major role in determining the occurrence of retrograde signaling by endocannabinoids [24] and [25].
Experiments are being performed to extend this mode of action also to CB2 receptors or to nonneuronal cells, including lymphocytes, macrophages, and microglial cells (for the control of the immune and inflammatory responses) [26] and [27]; endothelial cells (for the control of vascular tone and angiogenesis) [28]; adipocytes and pancreatic β cells (for the control of adipokine and insulin secretion) [29] or other endocrine cells [30]; and to reproductive tissues [31] and [32]. For example, the tight control in time and space of endocannabinoid biosynthesis and degradation within the framework of the chemical communication between the fertilized egg and cells of the oviduct and uterus is crucial for the correct implantation of the embryo [33]. Thus, although, like the endorphins, they exert a homeostatic function, the endocannabinoids, ultimately due to their chemical nature and peculiar biosynthetic pathways (and to the fact that constitutive CB1 receptors are much more widely distributed than originally thought, whereas CB2 receptors appear to be upregulated under several pathological conditions), play a local and yet more general function, seemingly regarding all aspects of animal health and disease (Table S1).
Faces and Facets of Endocannabinoid Metabolic Pathways and Enzymes
The interplay between chemistry and biology played a major role in the identification of the enzymes catalyzing endocannabinoid synthesis and degradation. The fatty acid amide hydrolase (FAAH), which catalyzes the hydrolysis of anandamide (and of other bioactive fatty acid amides, see below) and 2-AG, was isolated after the synthesis of inhibitors [34], which were then used for affinity chromatography purification of the enzyme. This eventually led to the cloning of FAAH [35], now considered to be a promising target for the development of new anxiolytic and analgesic drugs [36], [37] and [38]. Also, the X-ray structure of FAAH was obtained thanks to the fact that a “modified version” of the purified enzyme yields good crystals only when covalently bound to an irreversible active-site inhibitor [39]. As to the cloning of the DAGL-α and -β catalyzing 2-AG formation from diacylglycerols, this was achieved by using a bioinformatic approach, i.e., starting from the gene encoding a DAGL from Penicillium, and then “fishing” for orthologs in the sequenced genomes of increasingly complex animal organisms, ending with the human genome [16].
FAAH is an unusual enzyme since, unlike most serine hydrolases which employ a Ser-His-Asp triad, its catalytic mechanism involves a Ser-Ser-Lys triad [40] (Figure 2). This is consistent with mutagenesis and enzymological studies indicating that Ser241 plays a critical role as both acid and base in the hydrolytic cycle, whereas Lys142 is the activator of Ser241 [41] and [42]. Mutagenesis studies also involve Ser217, a residue conserved in all enzymes with an amidase signature sequence, in the catalytic mechanism of FAAH. This residue may act as a “bridge” that, through a proton shift, facilitates both the nucleophile attack and the exit of the leaving group. The FAAH crystal structure revealed the existence of an acyl chain-binding (ACB) channel for entry of hydrophobic substrates and a cytoplasmatic access (AC) channel for hydrophilic compounds, i.e., water for substrate hydrolysis and hydrophilic breakdown products. This latter channel is also likely to accommodate the polar head of anandamide and other fatty acid amides [40] and [43] (Figure 2). Despite its atypical catalytic mechanism, FAAH is inhibited by most classical serine hydrolase inhibitors, including trifluoromethyl ketones, fluorophosphonates, carbamates, and α-ketoheterocycle compounds (Table S2). The inhibitory mechanism of these compounds is based on the presence in their structures of a strong electrophile that engages the Ser241 nucleophile in either a covalently reversible or irreversible manner. However, the systematic evaluation of the selectivity of these FAAH inhibitors against other Ser hydrolases is necessary to delineate their therapeutic potential. A chemical proteomic approach known as “activity-based protein profiling” (ABPP) has been used to assess the selectivity of several FAAH inhibitors [44]. ABPP methods, by using active site-directed chemical probes, allow for the screening of inhibitors against multiple enzymes in parallel, and consequently for the detection of possible off-target enzymes [45]. More recently, a multidimensional protein-identification technology (MudPIT) was employed to identify the major off-targets for several FAAH inhibitors [46]. Using this method, it was shown that the carbamate compounds known as URB-597 [36] and BMS-1 (but not SA-72 [47]), the carbamoyl tetrazole LY2077855, and the α-keto-heterocycle OL-135 [37] act on off-targets [44], [45] and [46] (Table S2). Also, the recently developed irreversible inhibitors of DAGLs [48] are ideal candidates to be investigated with proteomics-type strategies. These compounds, known as O-3841 and O-3640, are fluorophosphonate derivatives of oleic acid and are at least selective against other proteins of the endocannabinoid system.
Figure 2. Schematic Representation of the Binding Site of Fatty Acid Amide Hydrolase
Schematic representation of the active site of fatty acid amide hydrolase (FAAH), with “hydrophobic” and “polar head” pockets (“ACB” and “AC” channels, respectively) to accommodate anandamide and other fatty acid amides, as deduced from crystallographic studies [39] and structure-activity relationship studies carried out with several analogs of FAAH inhibitors [43]. Note how the “AC” channel can theoretically accommodate bulkier groups than ethanolamine. Arachidonoyl-trifluoromethylketone (TFMK) and its analogs [34] were used for the affinity chromatography purification of FAAH [35], whereas methyl-arachidonoyl-fluoro-phosphonate (MAFP) was used to obtain crystals from a slightly modified and purified form of FAAH [39]. Carbamate inhibitors like URB597 (see also Table S2) were suggested to enter the active site in a way opposite that of the fatty acid derivatives, with the ester rather than the amide bond being cleaved by the catalytic action of Ser241 [43].
In view of the “only when and where needed” character of their action, and of the increasing evidence that endocannabinoids participate in several pathological conditions [10], it can be foreseen that inhibitors of their biosynthesis or catabolism will be used for the pharmacological treatment of disorders ranging from neuropathic pain and psychiatric/neurological disorders to hypertension and obesity, possibly in a more selective way than with cannabinoid receptor agonists (see [49] for a comprehensive review). However, two peculiar aspects of endocannabinoid metabolic pathways should call for caution when it comes to their therapeutic exploitation (Figure 3): (1) the high degree of redundancy with which endocannabinoids are made and/or degraded—this means that, for example, inhibiting just one of the several pathways that have been suggested so far for anandamide biosynthesis from N-arachidonoyl-phosphatidylethanolamine [50], [51] and [52], or only one of the several enzymes (FAAH, MAGLs, COX-2) that have been suggested to catalyze 2-AG hydrolysis [10] and [53], might not be sufficient to manipulate anandamide or 2-AG tissue levels, respectively; and (2) the observation that endocannabinoids, as with other bioactive lipids, are part of a sequence of enzymatic reactions leading to a corresponding sequence of chemical signals with distinct molecular targets and biological outputs. 2-AG, for example, is at the same time the product of a family of fundamental intracellular signals, the diacylglycerols, and the precursor of prostaglandin glycerol esters (via COX-2), suggested to act at noncannabinoid receptors [54], or of arachidonic acid (via MAGL), the progenitor of a plethora of mediators and an intracellular mediator itself. Thus, the blockade of DAGLs might not only reduce endocannabinoid signaling, but also may enhance protein kinase C-mediated signals, whereas inhibition of MAGL might lead to the accumulation of prostaglandin glycerol esters. Although it is likely that cellular and subcellular compartmentalization intervenes to segregate these potentially concurring pathways, and perhaps also to ensure that only one pathway contributes to the formation or inactivation of anandamide and 2-AG acting at cannabinoid receptors in a certain cell or tissue (Figure 3), much work remains to validate the efficacy and selectivity in vivo of inhibitors of endocannabinoid metabolism.
Figure 3. Redundancy, Functional Plasticity, and Target Multiplicity of Endocannabinoid Metabolic Pathways
(A) The three pathways proposed for N-arachidonoylphosphatidyl-ethanolamine conversion into anandamide as an alternative to the one represented in Figure S1 [50], [51] and [52]. Although speculative, it is possible that the multiplicity of the biosynthetic pathways of anandamide reflects to some extent its capability to interact at a submicromolar concentration with several molecular targets [126], including, in addition to cannabinoid receptors, opposing actions on TRPV1 (activation) and TRPM8 (inhibition) [127] channels (see Figure 5).
(B) Biosynthesis and degradation of 2-arachidonoylglycerol seen as a sequence of different signals acting on different targets at different times. Apart from being converted, as discussed in the text, to arachidonic acid and to a COX-2 derivative with specific targets, 2-AG can be transformed into, and produced from, 2-arachidonoyl-lysophosphatidic acid, which activates LPA receptors with relatively high homology with CB1 receptors [128]. Abbreviations: Abh4, α/β-hydrolase 4; CB1, CB2, cannabinoid receptors of type 1 and 2, respectively; COX-2, cycloxygenase-2; FAAH, fatty acid amide hydrolase; GPCR, G protein-coupled receptor; LPA, lysophosphatidic acid; lyso-PLD, lyso-phospholipase D; MAGL, monoacylglycerol lipase; PKC, protein kinase C; sPLA2, secretory phospholipase A2, PLC, phospholipase C; PGE2, prostaglandin E2; PTPN22, protein tyrosine phosphatase N22; TRPM8, transient receptor potential melastatin type 8 channel; TRPV1, transient receptor potential vanilloid type 1 channel.
Recent data have suggested, however, that some widely used pharmaceuticals might owe some of their therapeutic actions to the interaction with endocannabinoid-biosynthesizing or -inactivating proteins. In particular, some nonsteroidal anti-inflammatory drugs (NSAIDs) (Figure 4) possess this property. Indomethacin exerts anti-inflammatory actions that are partly antagonized by a CB2 receptor antagonist [55], whereas ibuprofen enhances the analgesic actions of anandamide in a way sensitive to both CB1 and CB2 antagonists [56], and flurbiprofen inhibits the spinal release of proalgesic peptides in a way that is antagonized by a CB1 antagonist [57]. Rofecoxib, a COX-2 inhibitor, synergizes with anandamide while elevating the tissue levels of anandamide and other analgesic fatty acid ethanolamides [58]. Indeed, one possible way to explain these findings is by suggesting that these NSAIDs also inhibit FAAH, as already shown by Fowler and collaborators for ibuprofen in 1997 [59]. More recently, the same group extended this property to other acidic NSAIDs, and they showed that it becomes more important when the extracellular pH is lower than 7, as during inflammatory conditions [60]. Meanwhile, other indomethacin derivatives, such as indomethacin methyl ester and indomethacin morpholinylamides (Figure 4), were also found to directly activate CB1 and CB2 receptors, respectively [61] and [62]. More intriguingly, a recent study [63] showed that, in rats and mice, acetaminophen (paracetamol) is converted in vivo into p-aminophenol and then N-arachidonoyl-phenolamine (AM404) (Figure 4), a compound capable of inhibiting both FAAH and anandamide cellular reuptake and elevating anandamide tissue levels [64] and [65]. The second reaction is catalyzed by FAAH (an enzyme that, under certain conditions, can facilitate the condensation of fatty acids with amines), thus opening the possibility that it might also occur with other aromatic amines used in the clinic and lead to aromatic amides capable of interacting with other proteins of the endocannabinoid system. Importantly, the analgesia on a hot plate of acetaminophen is blocked by CB1 receptor antagonists, thus confirming that this widely used drug does also act through enhancement of the endocannabinoid system [66].
Figure 4. Chemical Structures of Widely Used Therapeutic Drugs that Have Been Reported to Interact with Proteins of the Endocannabnoid System
The cycloxygenase inhibitor indomethacin, and some of its derivatives, were suggested to directly bind to and activate CB1 and/or CB2 receptors [61] and [62]. Despite the lack of chemical similarity with anandamide, the NSAIDs, rofecoxib, ibuprofen, and flurbiprofen, and the general anesthetic propofol were suggested to act, in part, by inhibiting FAAH-catalyzed anandamide degradation [56], [57], [58], [59], [60] and [67]. The NSAID acetaminophen, instead, was shown to act, in part, through the conversion into AM404 and subsequent indirect activation of cannabinoid receptors [63] and [66]. The antiobesity drug orlistat (tetrahydrolipstatin) was shown to potently inhibit the biosynthesis of 2-arachidonoylglycerol [16] and [48].
NSAIDs are not the only therapeutic drugs capable of interacting with endocannabinoid enzymes. The general anesthetic propofol (Figure 4) also inhibits FAAH, and a part of its sedating properties is due to the subsequent elevation of the brain levels of anandamide, which, via CB1 receptors, can induce sleep [67]. More recently, the antiobesity drug tetrahydrolipstatin (orlistat) (Figure 4) was shown to inhibit DAGL-α and -β and, hence, to reduce 2-AG levels in intact cells, at concentrations lower than those necessary to inhibit other lipases [16] and [48]. Although this compound inhibits obesity mostly by acting at the level of lipid assimilation, it is tempting to speculate that part of its actions are due to inhibition of 2-AG-induced, and CB1-mediated, gastrointestinal actions [68]. In summary, from these data the intriguing possibility emerges that we might already be using in the clinic, without knowing it, substances that act in part by manipulating endocannabinoid levels.
Back to Plants: Are Endocannabinoids Like Chili Peppers?
The chemical structure of anandamide is not so different from that of capsaicin (Figure 5A), the pungent fatty acid amide component of another plant with a long history of medicinal and nutritional use, the hot chili pepper Capsicum annuum. In fact, capsaicin is even more chemically similar to the aforementioned AM404 (Figure 4), which inhibits anandamide degradation [64] and [65]. After the identification by Caterina and colleagues [69] of the transient receptor potential vanilloid-type 1 channel (TRPV1, originally known as vanilloid VR1 receptor) as the molecular target of capsaicin (Figures 5B and 5C), we and others, based on these chemical considerations, began to investigate the possibility that this receptor and proteins of the endocannabinoid system share common ligands [70]. Compounds were synthesized that bind to CB1 receptors, FAAH, or the putative anandamide membrane transporter (Figure S1), on the one hand, and to TRPV1, on the other hand [71] and [72]. More importantly, it was possible to demonstrate that anandamide activates TRPV1 receptors [73] and [74]. Later, other long-chain fatty acid ethanolamides, i.e., the naturally occurring homologs of anandamide (Figure 5A), and AM404 itself, were found to stimulate the activity of TRPV1 receptors [72], [75], [76], [77] and [78], and to share this property with other derivatives of arachidonic acid [79]. Molecular-modeling techniques were used to demonstrate that the preferential conformations of these compounds in solution overlap with those of capsaicin [78] and [79] (Figure 5D). However, none of these endogenous compounds appeared to be nearly as potent as capsaicin at inducing TRPV1-mediated biological responses. Although we now know that the “vanilloid” activity of these compounds is dramatically increased by several regulatory factors [80], this observation, together with the original belief that vanilloid TRPV1 receptors, by being mostly expressed in sensory afferents, are used as receptors only for external painful stimuli (high temperature, low pH, plant toxins), seemed to rule out the existence of true “endovanilloids.”
Figure 5. Vanilloid Receptors and Endovanilloids
(A) Chemical structures of N-acyldopamines and oleoylethanolamide, identified after the discovery of endocannabinoids and of the receptors for capsaicin and resiniferatoxin, the transient receptor potential vanilloid type 1 (TRPV1) channel.
(B) Three-dimensional representation of a TRPV1 monomer with the binding site for capsaicin according to Jordt and Julius [129]. According to this model, aromatic stacking of the vanillyl moiety of capsaicin (as well as anandamide) with Tyr511 in the intracellular T2-T3 linker region stabilizes the binding of the aliphatic chain with a transmembrane site created by the T3 and T4 domains. The observation that the T2-T3 linker domain plays a crucial role in ligand recognition in both TRPV1 receptor and the menthol and “cold”-receptor, TRPM8, led to the identification of anandamide and NADA as TRPM8 antagonists [127].
(C) Model proposed by Gavva and colleagues according to which capsaicin, anandamide, and N-arachidonoyldopamine (NADA) bind to Tyr511 through hydrophobic binding with their aliphatic chain, whereas residues Trp549 and Thr550 are involved in binding with the vanillyl or cathecolamine moieties of capsaicin and NADA, respectively [130].
(D) Overlap of capsaicin and oleoylethanolamide conformations in solution, according to the molecular model proposed by Movahed et al. [78].
Meanwhile, however, increasing and conclusive evidence was obtained for the presence of TRPV1 receptors in the brain [81], [82] and [83], where these proteins are unlikely to be reached by exogenous stimuli, thus strongly suggesting the existence of endovanilloid ligands [84]. Considerations on the structure-activity relationships of synthetic vanilloid TRPV1 agonists, which indicated the necessity of (1) a long, unsaturated alkyl chain, (2) a secondary amide group, and (3) 3-hydroxy-4-methoxy substituents on the aromatic moiety, in order to achieve optimal interaction with the receptors [85] and [86] (Figure 5C), together with the realization that these prerequisites could be met, to some extent, only by putative endogenous amides of dopamine with long, unsaturated fatty acids, led first to the synthesis [87] and then the isolation from the brain of N-arachidonoyl- and N-oleoyl-dopamine [88] and [89]. These compounds (Figure 5A; Table 1) are the most potent and efficacious endovanilloids identified to date and are most abundant in brain regions rich in dopamine, in agreement with their potential role as endogenous TRPV1 activators and with their possible biosynthetic origin from the N-acylation of dopamine. They are accompanied by saturated homologs that, although inactive per se on TRPV1, are capable of enhancing the activity of other endovanilloids [90]. Thus, once again, the meeting of chemical and biological minds led to the finding of endogenous counterparts of a plant natural product. The importance of the discovery of N-acyl-dopamines, however, went beyond that of finding potent endogenous ligands for TRPV1 receptors, since it supported the hypothesis that animal tissues might make, and use as chemical signals, any combination between fatty acids and biogenic amines.
The possible combinations of amino acids or biogenic amines and the most abundant fatty acids found in mammalian tissues yield new potential endogenous mediators: the N-acyl-ethanolamines, N-acyl-dopamines, N-acyl-amino acids, and N-acyl-taurines [97], [98], [99] and [100]. Fatty acid primary amides have also been identified [135] and [136]. The targets and metabolism of only a few of the several hundred possible compounds have been determined to date [103], [104], [105], [106] and [107] and are summarized here. R2 = C12:0, C14:0, C16:0, C18:0, C18:1, C18:2, C18:3, C20:0, C20:3, C20:4, C22:0, C22:4, C22:5, C22:6, C24:0, C24:1 alkyl chains; R3 = residues of amino acids or GABA. COMT, catecholamine-O-methyl-transferase; FAAH, fatty acid amide hydrolase; PPAR, peroxisome-proliferator-activated receptor; TRPV, transient receptor potential vanilloid-type.
Bioactive Fatty Acid Amides: When Animal Cells Play Combinatorial Chemistry
That cells could “combine” different fatty acids and biogenic amines to make several possible permutations of different fatty acid amides had been deduced already from the discovery in rodents of N-acyl-amino acids such as N-arachidonoyl-glycine (NAGly) and N-arachidonoyl-alanine (Table 1), which share with fatty acid ethanolamides like anandamide a potent analgesic and anti-inflammatory activity and the property of being recognized by FAAH as substrates [91], [92] and [93]. This finding raised the possibility that any long-chain fatty acid available in tissues could be amidated with any of the 20 amino acids and their naturally occurring derivatives. This would lead to the origination of hundreds of potential endogenous mediators with functions and molecular targets to be discovered. This possibility seems to be confirmed by the recent identification of N-arachidonoyl-serine, a brain constituent with vasodilatory and anti-inflammatory activity [94], and by increasing evidence for the presence in rodent tissues of 40 other postulated fatty acyl amides [95] and [96].
How is chemical-biological research going to cope with this “invasion” of new small-molecule mediators? How to discover and measure their levels in tissues, reveal their metabolic pathways, understand their physiological and pathological roles and, most importantly, identify their molecular targets? Clearly, the employment of the most modern “omic” approaches for gene, protein, and metabolite profiling will be required to find a function and a “parent receptor” to these orphan mediators, as well as to guide their discovery. Some progress in this direction has already been made. For example, based on the assumption that at least some of these compounds would be FAAH substrates, Cravatt and collaborators used an original global metabolite-profiling strategy, consisting of comparing, by the use of liquid chromatography-electrospray-mass spectrometric (LC-ESI-MS) techniques, the lipid components of tissues from wild-type and FAAH null mice, to identify new fatty amides. This led to the identification of N-acyl-taurines (Table 1) as new endogenous amides whose levels are controlled by this enzyme [97] and [98]. A similar approach, using FAAH null mice treated with anandamide, led to the identification of a potential alternative pathway for the inactivation of this compound and other acylethanolamides through the formation of the corresponding O-phosphorylcholine derivatives [99]. Other comparisons between lipid profiles, for example those of distinct brain areas from mice at different phases of their estrous cycle [100], can be used to understand the function of the analytes. Multidimensional (tandem) mass spectrometric techniques applied to other types of lipidomic-like approaches 101 M.R. Wenk, The emerging field of lipidomics, Nat. Rev. Drug Discov. 4 (2005), pp. 594–610. View Record in Scopus | Cited By in Scopus (204)[101] and [102] also seem to be very promising for the discovery of even trace quantities of fatty acid amides belonging to several families, or for the analysis of already discovered compounds [95] and [100]. Thanks to the use of “common fragment” methods, all of the naturally occurring members of the same family of fatty acid amides with different acyl chains but yielding common fragments after MS-MS (Table 1) can be analyzed in the same run (see Figure S2). Furthermore, the use of the optimal chromatographic conditions and of LC-ESI-MS-MS allows for the analysis of several fatty acid amide classes at the same time.
Progress is also being made in the identification of receptors for bioactive fatty acid amides. Some serendipitous but nevertheless important discoveries, i.e., that oleoylethanolamide binds to and activates peroxisome proliferator-activated receptor α [103], or that N-arachidonoyl-serine activates an as-yet-unidentified endothelial cannabinoid receptor [94], were prompted by the pharmacological actions observed for these compounds. N-acyl-taurines, like acylethanolamides and acyldopamines, activate TRPV1 receptors, but they also gate a related plasma membrane cation channel, the TRPV4 receptor [104]. Also, the finding of two GPCRs, GPR119 and GPR18, as high-affinity receptors for oleoylethanolamide and NAGly, respectively [105] and [106], was the result of targeted approaches. The implications of industrial patents claiming that GPR55 might be a high-affinity target for palmitoylethanolamide have also been recently discussed [107]. However, in view of the observation that bioactive fatty acid amides can be promiscuous in their targets, and that the latter, as with other lipid mediators, encompass all types of receptors (i.e., GPCRs, nuclear receptors, ion channels [Figure 3]), it can be foreseen that more systematic approaches, such as the use of biospecific interaction analysis (BIAcore), protein or mRNA arrays, and even of virtual screening methodologies, will have to be used in the future for the “deorphanization” of these novel compounds and, at the same time, of the 150 G protein-coupled and 24 nuclear “orphan” receptors still awaiting assignment of endogenous ligands. These techniques, together with the MS methods mentioned above, will have to be applied to also investigate if other amides of fatty acids, for example with serotonin, histamine, adrenaline, and noradrenaline, as well as with trace amines, occur in mammalian tissues. Some of these compounds (e.g., N-arachidonoyl-serotonin, Figure 6) have already been synthesized and exhibit interesting pharmacological properties (see below).
Figure 6. “Tinkering” with Nature's Building Blocks
Combining the vanillyl moiety typical of several plant natural products with arachidonic acid or ricinoleic acid, and the further modification of the chemical structures, yields compounds with mixed activity at cannabinoid and vanilloid TRPV1 receptors, i.e., arvanil, O-1861, and phenyl-acetyl-ricinoleoyl-cyclopropylamide [71], [108] and [109]. The synthetic N-arachidonoyl-serotonin mimics Nature's capability to make amides between long-chain fatty acids and biogenic amines, and turned out to be a selective inhibitor of fatty acid amide hydrolase (Table S2) and a potent antagonist at TRPV1 channels [38] and [110]. Iodination of the vanillyl moiety of a natural compound like resiniferatoxin (RTX), or of synthetic natural product derivatives, such as the acetylvanillyl ester of resiniferol orthophenylacetate (ROPA) and nor-dihydrocapsaicin, can produce opposing effects on the activity at TRPV1 channels [111], [112], [113] and [114]. The combination of a natural product like olivetol and a long-chain fatty acid yielded CB-25, a potent cannabinoid receptor ligand with “protean” agonist activity in vitro and in vivo [115], [116] and [117]. Isobutyl analogs of anandamide are more potent than the parent compound at cannabinoid receptors, and this is perhaps the reason why the Echinacea components dodeca-2E,4E,8Z,10Z-tetraenoic acid- and dodeca-2E,4E-dienoic acid-isobutylamide are the only plant natural products apart from cannabinoids that activate cannabinoid CB2 receptors quite potently [118], [119], [120] and [121].
Think Like a Tinker: Making Endocannabinoid-Based Drugs with Nature's Bits and Pieces
If nature can combine chemical moieties to make small, multitarget chemical signals via dedicated metabolic pathways, the synthetic chemist can also put together naturally occurring building blocks to make drugs that can interact with multiple receptor types, thus obtaining, in theory, more efficacious and therapeutically useful pharmacological tools. Given the overlap between the potential clinical applications (pain, inflammation, emesis, cancer, etc.) and binding recognition properties of proteins of the endocannabinoid system and TRPV1 channels, one strategy to develop hybrid therapeutic drugs was to put together fatty acids and the vanillyl moiety of capsaicin, each opportunely modified in order to maximize the interaction of the end product with each postulated target. N-arachidonoyl-vanyllamide (arvanil) and its analog, O-1861 (Figure 6), were synthesized with this idea in mind, and they proved to be capable of potently activating TRPV1 receptors while acting as agonists at CB1 receptors and inhibitors of the cellular reuptake of anandamide [71] and [108]. Both compounds turned out to be more potent and efficacious analgesics than pure cannabinoid or vanilloid receptor agonists with comparable affinities for their respective receptors. The derivatization of the hydroxy group of ricinoleic acid, followed by amidation with chemically modified ethylamine “heads,” yielded compounds with antagonist/inverse agonist activity at CB2 receptors and agonist activity at TRPV1 receptors and, hence, potential application against inflammation [109]. The aforementioned N-arachidonoyl-serotonin not only inhibits FAAH, thus elevating endocannabinoid levels and acting as an indirect cannabinoid receptor agonist [110], but it is also a potent TRPV1 antagonist in vitro and in vivo, thus exhibiting equivalent activity against neuropathic pain as other compounds that are more potent at FAAH [38].
However, tinkering with natural products can also lead to unexpected results. For example, 5′-iodination of resiniferatoxin on its vanillyl moiety (Figure 6) transforms the ultrapotent agonist activity at TRPV1 channels of this plant toxin into the capability to antagonize these receptors, whereas 6′-iodination only weakens its agonist activity [111]. By converse, 6′-, rather than 5′-, iodination of the much less hindered nordihydrocapsaicin (the saturated analog of capsaicin) and of other vanillamide TRPV1 ligands is required to transform their agonist activity into potent TRPV1 antagonists [112], without decreasing the capability of some of these compounds to directly inhibit NF-kB activity, thus yielding dual target anti-inflammatory and proapoptotic agents [113]. Even more intriguingly, 5′-iodination of the acetylvanillyl ester of resiniferol orthophenylacetate, a resiniferatoxin analog (Figure 6), yields a compound that, instead of behaving as an antagonist (as in the case of 5′-I-resiniferatoxin) or of losing activity (as in the case of 6′-I-resiniferatoxin), is 5-fold more potent as an agonist than the noniodinated analog [114]. On the “cannabinoid side,” attaching a C-11 alkylamide “head” to olivetol, a plant-derived compound, led to compounds that, despite their limited conformational freedom compared to endocannabinoids, bind with higher affinity to both CB1 and CB2 receptors [115]. In this case, the surprise came from the dramatically different behavior of one these compounds (CB-25, Figure 6) in vitro and in vivo, where it can act as a CB1 partial agonist and CB2 “silent” antagonist or as a CB1 antagonist, respectively [116], thus belonging to the ever growing family of receptor “protean agonists” (i.e., compounds that can exhibit agonist, antagonist, or inverse agonist activities depending on the constitutive “tone” of their receptors [117]).
If man can imitate nature by making hybrid drugs, Nature can also imitate the human body by making endocannabinoid-like natural products that potently bind to cannabinoid receptors. This is the case for the alkylisobutylamides from the roots of Echinacea angustifolia [118], [119] and [120]. These compounds, and in particular dodeca-2E,4E,8Z,10Z-tetraenoic acid- and dodeca-2E,4E-dienoic acid-isobutylamide (Figure 6), bind to CB2 receptors with higher affinity than endocannabinoids, although this property explains only part of their strong immunomodulatory and anti-inflammatory properties [121]. The crosstalk between man and Nature extends even further since C18:1 and C18:2 fatty acid ethanolamides and their corresponding phospholipid precursors are also found in higher plant seeds and leaves [122] and [123], in which a functional homolog of the mammalian FAAH has been cloned [124]. These anandamide congeners are inactive at cannabinoid receptors but play a role in the control of plant growth via unidentified molecular targets [124] and [125]. These chemical, but not necessarily functional, similarities between plant metabolites and mammalian mediators underscore the global importance of certain metabolic pathways in eukaryotes, and they emphasize how cells from phylogenetically distant species can exploit similar building blocks and anabolic/catabolic strategies to respond to different biological demands.
Take Home Messages and Open Questions
From the data reviewed in this article it is clear that biological and pharmacological studies carried out with a chemical mind can reveal new physiological and pathological mechanisms and, eventually, solve clinical problems. The exciting walk from the psychotropic constituent of Cannabis to the understanding of the mechanism of its biological actions led to the discovery of the endocannabinoid system, a signaling apparatus whose function goes well beyond what could have been imagined from pharmacological studies on THC. The route from the endocannabinoids to the Capsicum pungent principle then led to the finding of endovanilloids, endogenous mediators whose role is yet to be fully understood. The discovery of endocannabinoids and endovanilloids paved the way for the finding of several other lipid signals, and it prompted, on the one hand, new strategies for the chemical synthesis of compounds with multiple pharmacological and therapeutic targets, and, on the other hand, the search for chemically similar compounds back in plants. Many open questions to which the meeting of chemistry and biology can provide an answer still remain. Just to name a few, these questions involve the understanding of the mechanisms and exact physiological meaning of the target and metabolic pathway promiscuity of fatty acid ethanolamides; the identification of the elusive protein(s) facilitating endocannabinoid membrane transport; the receptor “deorphanization” of the several tens of bioactive fatty acid amides that have been discovered, and their testing on the several TRP channels that have been identified so far, many of which are, like TRPV1, activated by plant natural products; the determination of the exact function and molecular targets of fatty acid ethanolamides in plants; and the understanding of the mechanism of action in animals of other phytocannabinoids, like the therapeutically promising cannabidiol. Thus, the exciting promenade from plant natural products to animal physiology and back might soon become a true treasure hunt.
Hemopressin is a 9 amino acid peptide derived from alpha-hemoglobin, the main constituent of red blood cells.
Hemopressin is a short, nine amino acid peptide (H-Pro-Val-Asn-Phe-Lys-Leu-Leu-Ser-His-OH) isolated from rat brain that behaves as an inverse agonist at the cannabinoid receptor CB1, and is shown here to inhibit agonist-induced receptor internalization in a heterologous cell model. Since this peptide occurs naturally in the rodent brain, we determined its effect on appetite, an established central target of cannabinoid signaling. Hemopressin dose-dependently decreases night-time food intake in normal male rats and mice, as well as in obese ob/ob male mice, when administered centrally or systemically, without causing any obvious adverse side effects. The normal, behavioral satiety sequence is maintained in male mice fasted overnight, though refeeding is attenuated. The anorectic effect is absent in CB1 receptor null mutant male mice, and hemopressin can block CB1 agonist-induced hyperphagia in male rats, providing strong evidence for antagonism of the CB1 receptor in vivo. We speculate that hemopressin may act as an endogenous functional antagonist at CB1 receptors and modulate the activity of appetite pathways in the brain.
On the other hand, the 11- and 12-residue forms of hemopressin are likely to represent the endogenous forms, and further studies in the field should use these peptides if the goal is to characterize the functions of naturally-occurring peptides.
Che FY, Zhang X, Berezniuk I, Callaway M, Lim J, Fricker LD (2007) Optimization of neuropeptide extraction from the mouse hypothalamus. J Proteome Res 6: 4667-4676.
Fricker LD (2010) Analysis of mouse brain peptides using mass spectrometry-based peptidomics: implications for novel functions ranging from non-classical neuropeptides to microproteins. Mol Biosyst.
Gelman JS, Sironi J, Castro LM, Ferro ES, Fricker LD (2010) Hemopressins and other hemoglobin-derived peptides in mouse brain: Comparison between brain, blood, and heart peptidome and regulation in Cpefat/fat mice. J Neurochem in press.
Gomes I, Grushko JS, Golebiewska U, Hoogendoorn S, Gupta A, Heimann AS, Ferro ES, Scarlata S, Fricker LD, Devi LA (2009) Novel endogenous peptide agonists of cannabinoid receptors. FASEB J 23: 3020-3029.
Heimann AS, Gomes I, Dale CS, Pagano RL, Gupta A, de Souza LL, Luchessi AD, Castro LM, Giorgi R, Rioli V, Ferro ES, Devi LA (2007) Hemopressin is an inverse agonist of CB1 cannabinoid receptors. Proc Natl Acad Sci U S A 104: 20588-20593.
Rioli V, Gozzo FC, Heimann AS, Linardi A, Krieger JE, Shida CS, Almeida PC, Hyslop S, Eberlin MN, Ferro ES (2003) Novel natural peptide substrates for endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme. J Biol Chem 278: 8547-8555.

April 18

2011-04-18T15:58:00.000-07:00

[0026] Fatty acid amide hydrolase (FAAH) is an enzyme that hydrolyzes the fatty acid amide (FAA) family of endogenous signaling lipids. General classes of FAAs include the N- acylethanolamines (NAEs) and fatty acid primary amides (FAPAs). Examples of NAEs include anandamide (AEA), palmitoylethanolamide (PEA) and oleoylethanolamide (OEA). An example of
FAPAs includes 9-Z-octadecenamide or oleamide. (McKinney MK, Cravatt BF. 2005. Annu Rev Biochem 74:411-32)].
[0027] Diseases, disorders, syndromes and/or conditions, that would benefit from inhibition of FAAH enzymatic activity include, for example, Alzheimer's Disease, schizophrenia, depression, alcoholism, addiction, suicide, Parkinson's disease, Huntington's disease, stroke, emesis, miscarriage, embryo implantation, endotoxic shock, liver cirrhosis, atherosclerosis, cancer, traumatic head injury, glaucoma, and bone cement implantation syndrome.
Other diseases, disorders, syndromes and/or conditions that would benefit from inhibition of FAAH activity, include, for example, multiple sclerosis, retinitis, amyotrophic lateral sclerosis, immunodeficiency virus-induced encephalitis, attention-deficit hyperactivity disorder, pain, nociceptive pain, neuropathic pain, inflammatory pain, non-inflammatory pain, painful hemorrhagic cystitis, obesity, hyperlipidemia, metabolic disorders, feeding and fasting, alteration of appetite, stress, memory, aging, hypertension, septic shock, cardiogenic shock, intestinal inflammation and motility, irritable bowel syndrome, colitis, diarrhea, ileitis, ischemia, cerebral ischemia, hepatic ischemia, myocardial infarction, cerebral excitotoxicity, seizures, febrile seizures, neurotoxicity, neuropathies, sleep, induction of sleep, prolongation of sleep, insomnia, and inflammatory diseases. [0028] Carbamic acid esters have shown promise as selective FAAH inhibitors (Kathuria et al., Nat. Med. 2003, 9:76-81). In particular, a series of alkylcarbamic acid aryl esters, such as, for example, the compound of Formula (I) disclosed herein, have been shown to be potent and selective inhibitors of FAAH activity. Mor et al. (J. Med. Chem. 2004, 47:4998-5008; incorporated by reference) and Piomelli et al. (International Patent Publication No. WO 2004/033422; incorporated by reference) disclosed representative alkylcarbamic acid aryl esters of Formula (I) that are potent inhibitors of FAAH activity, but do not significantly interact with selected serine hydrolases or with cannabinoid receptors. Among the disclosed alkylcarbamic acid esters of Formula (I), the compound cyclohexylcarbamic acid 3'-carbamoylbiphenyl-3-yl ester (also known as 5'- carbamoylbiphenyl-3-yl cyclohexyl carbamate, UCM597 and URB597; referenced herein as compound KDS-4103) was identified as a potent and selective inhibitor of FAAH activity.
First, chronic unpredictable stress, used to model anhedonia, a core depression symptom, is associated with decreased endocannabinoid 2-arachidonoylglycerol in the rat hippocampus (Hill et al., 2005). Second, in humans, upregulation of PFC CB1R in suicidal depressives may indicate an adaptive response to decreased endocannabinoids (Hungund et al., 2004). Third, randomized trials of the CB1R antagonist rimonabant for obesity management increased adverse effects of depression and anxiety (Bronander and Bloch, 2007).
Treatment with Delta(9)-THC did not produce significant changes in oxidative stress markers or in mRNA levels of CB1 and CB2 receptors in the liver of mice, but attenuated the increase in the selenium-dependent GPx activity (Delta(9)-THC: 8%; VCtrl: 23% increase) and the GSH/oxidized GSH ratio (Delta(9)-THC: 61%; VCtrl: 96% increase), caused by treatment with the vehicle. Delta(9)-THC administration did not show any harmful effects on lipid peroxidation, protein carboxylation or DNA oxidation in the healthy liver of mice but attenuated unexpected effects produced by the vehicle containing ethanol/cremophor EL.
Whereas the CA1 region appears to process features of space, the DG processes orientation in space. Both phenomena are strongly associated with the expression of LTD in these hippocampal subregions. Taken together with our findings that persistent expression of LTP occurs in the DG and CA1 regions following exposure to novel empty space, one could speculate that LTP is generated as an instantaneous response to exposure to empty space. Superimposed on this phenomenon comes the processing of novel spatial orientation through LTD in the DG and the processing of novel spatial features through LTD in the CA1 region. The integration of these individual aspects of space results in the basis for a complete spatial map of a novel environment. This implies that feature-rich spatial memory is acquired by bidirectional synaptic plasticity and that in the subregions different types of functional spatial information trigger LTD.
Each of the 3 cannabis-associated cases of cerebellar infarction was confirmed by biopsy (1 case) or necropsy (2 cases) and showed inflammatory cellular reactions characteristic of a 1- to 3-day-old infarct (case 1) or a 3- to 7-day-old infarct (cases 2 and 3).3 In all 3 cases, the central nervous system infarction was acute and localized to cerebellum.
We previously presented a case of biopsy-proven cerebellar infarction involving multiple branch cerebellar arterial territories with a benign cerebral arteriogram in a 15-year-old male that was temporally related to heavy marijuana use, confirmed by toxicologic study. This patient presented with a 3-day history of headache, nausea, and unsteadiness of gait after a binge of marijuana smoking.
Brainstem compromise caused by cerebellar and cerebral edema led to death in the 2 fatal cases.
From the literature, it is clear that marijuana use can cause systemic hypotension, impair peripheral vasomotor reflexes, and may alter central nervous system blood flow and cerebral vascular autoregulation. Marijuana use has been associated with stroke in adults, but acute central nervous system infarction related to marijuana use is not well described in children. Although the mechanism of neurologic injury and its localization to the posterior circulation in these cases remains uncertain, our observation of acute cerebellar infarction in 3 adolescents shortly after marijuana use suggests that this drug may contribute to cerebellar vascular injury, possibly by causing vasospasm, especially in the inexperienced or episodic user, resulting in cerebellar ischemia.
Hemopressin is a 9 amino acid peptide derived from alpha-hemoglobin, the main constituent of red blood cells.
Hemopressin is a short, nine amino acid peptide (H-Pro-Val-Asn-Phe-Lys-Leu-Leu-Ser-His-OH) isolated from rat brain that behaves as an inverse agonist at the cannabinoid receptor CB1, and is shown here to inhibit agonist-induced receptor internalization in a heterologous cell model. Since this peptide occurs naturally in the rodent brain, we determined its effect on appetite, an established central target of cannabinoid signaling. Hemopressin dose-dependently decreases night-time food intake in normal male rats and mice, as well as in obese ob/ob male mice, when administered centrally or systemically, without causing any obvious adverse side effects. The normal, behavioral satiety sequence is maintained in male mice fasted overnight, though refeeding is attenuated. The anorectic effect is absent in CB1 receptor null mutant male mice, and hemopressin can block CB1 agonist-induced hyperphagia in male rats, providing strong evidence for antagonism of the CB1 receptor in vivo. We speculate that hemopressin may act as an endogenous functional antagonist at CB1 receptors and modulate the activity of appetite pathways in the brain.
On the other hand, the 11- and 12-residue forms of hemopressin are likely to represent the endogenous forms, and further studies in the field should use these peptides if the goal is to characterize the functions of naturally-occurring peptides.
Che FY, Zhang X, Berezniuk I, Callaway M, Lim J, Fricker LD (2007) Optimization of neuropeptide extraction from the mouse hypothalamus. J Proteome Res 6: 4667-4676.
Fricker LD (2010) Analysis of mouse brain peptides using mass spectrometry-based peptidomics: implications for novel functions ranging from non-classical neuropeptides to microproteins. Mol Biosyst.
Gelman JS, Sironi J, Castro LM, Ferro ES, Fricker LD (2010) Hemopressins and other hemoglobin-derived peptides in mouse brain: Comparison between brain, blood, and heart peptidome and regulation in Cpefat/fat mice. J Neurochem in press.
Gomes I, Grushko JS, Golebiewska U, Hoogendoorn S, Gupta A, Heimann AS, Ferro ES, Scarlata S, Fricker LD, Devi LA (2009) Novel endogenous peptide agonists of cannabinoid receptors. FASEB J 23: 3020-3029.
Heimann AS, Gomes I, Dale CS, Pagano RL, Gupta A, de Souza LL, Luchessi AD, Castro LM, Giorgi R, Rioli V, Ferro ES, Devi LA (2007) Hemopressin is an inverse agonist of CB1 cannabinoid receptors. Proc Natl Acad Sci U S A 104: 20588-20593.
Rioli V, Gozzo FC, Heimann AS, Linardi A, Krieger JE, Shida CS, Almeida PC, Hyslop S, Eberlin MN, Ferro ES (2003) Novel natural peptide substrates for endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme. J Biol Chem 278: 8547-8555.
Among all food additive-containing foods, the highest contributors were: soft drinks to benzoates intake, nuts and canned juices to sulphites intake, bread and biscuits to BHA intake and chewing gum to BHT intake.
We examined the food additive, butylated hydroxyanisole (BHA), for its capacity to modulate the cytotoxic effects of Δ9-tetrahydrocannabinol (THC). THC was not cytotoxic when added to cultures of A549 lung tumor cells at concentrations<5 μg/ml, but induced cell necrosis at higher levels with an LC50=16–18 μg/ml. BHA alone, at concentrations of 10–200 μM, produced limited cell toxicity but significantly enhanced the necrotic death resulting from concurrent exposure to THC. In the presence of BHA at 200 μM, the LC50 for THC decreased to 10–12 μg/ml. Similar results were obtained with smoke extracts prepared from marijuana cigarettes, but not with extracts from tobacco or placebo marijuana cigarettes (containing no THC). Two different mechanisms for this synergistic cytotoxicity were investigated. Experiments were repeated in the presence of either diphenyleneiodonium or dicumarol as inhibitors of the redox cycling pathway. Neither of these compounds protected cells from the effects of combined THC and BHA, but rather enhanced necrotic cell death. Measurements of cellular ATP revealed that both THC and BHA reduced ATP levels in A549 cells, consistent with toxic effects on mitochondrial electron transport. The combination was synergistic in this respect, reducing ATP levels to <15% of control. Exposure to marijuana smoke in conjunction with BHA, a common food additive, may promote deleterious health effects in the lung.
The effects of butylated hydroxyanisole (BHA), a commonly used food antioxidant, on oxygen consumption, ATPase activity, and the redox state of some electron carriers of rat liver mitochondria have been studied. It was observed that BHA slightly stimulated state 4 respiration but strongly inhibited ADP- and uncoupler-stimulated respiration on NAD+- and FAD-linked substrates. ATPase activity and vectorial H+ ejection were affected only slightly by BHA, suggesting that BHA predominantly inhibits mitochondrial electron flow. Experiments to determine its site of action showed that BHA did not noticeably affect electron flow through cytochrome oxidase; in contrast, NADH:duroquinone reductase activity and electron flow through ubiquinone-cytochrome b-cytochromec complex were inhibited strongly because the oxidation of duroquinol was affected markedly. The BHA block of electron transport was bypassed by both N,N,N′,N′-tettamethyl-p-phenyleaediamine and 2,6-dichlorophenolindophenol. Also, the presence of BHA changed the redox state of cytochrome b and C1 to a more oxidized level. These observations suggest that electron transport is inhibited by BHA at the NADH-ubiquinone and at the ubiquinone-cytochrome b levels. From Hill plots, it is clear that more than one binding site is involved in complete inhibition; in addition, available evidence suggests that there may be two sites at the substrate side of ubiquinone and another two sites at the oxygen side of ubiquinone. Consequently, mitochondrial ATP synthesis would be interrupted. This event could be related to the toxicity of BHA.
Exposure to marijuana smoke in conjunction with BHA, a common food additive, may promote deleterious health effects in the lung." BHA & BHT are human-made fat preservatives, and are found in many packaged foods including: plastics in boxed cereal, Jello, Slim Jims, and more
BHA is added to butter, lard, meats, cereals, baked
goods, sweets, beer, vegetable oils, potato chips, snack foods, nuts and
nut products, dehydrated potatoes, and flavoring agents. It is used in
sausage, poultry and meat products, dry mixes for beverages and desserts,
glazed fruits, chewing gum, active dry yeast, defoaming agents for beet
sugar and yeast, and emulsion stabilizers for shortenings.
BHA stabilizes the petroleum wax
coatings of food packaging (Sax and Lewis 1987). BHA is considered a
GRAS (generally recognized as safe) compound by the FDA when the
content of the antioxidant is not greater than 0.02% w/w of the total fat
or oil content of the food.
Fast food service personnel who normally cook and serve fried and oily
foods have the potential for high exposure to BHA.
Potential occupational exposure exists for workers in certain
industries, including food producers, animal feed producers, livestock
producers, cosmetic manufacturers, some petroleum workers, and
rubber producers and those who handle the end products such as tires.
BHA is used as a preservative and antioxidant in pharmaceutical
preparations and cosmetic formulations containing fats and oils (Osol
1980). Cosmetic-grade BHA reportedly contains a minimum of 90%
3-BHA and approximately 8% 2-BHA (IARC 1986). In a 1981 FDA
survey, BHA was reported to be used in 3,217 to 21,279 cosmetic
formulations; the majority (88%) of the reported concentrations was
≤0.1% (IARC 1986). One product, a lipstick, was reported to contain
>10% BHA. In this survey, lipstick formulations (1,256 products)
represented the highest use of BHA, with eye shadows being the next
highest (410 products). A widely used antioxidant mixture for
cosmetics contained 20% BHA, 6% propyl gallate, 4% citric acid, and
70% propylene glycol (Kirk-Othmer 1979a, IARC 1986).
Potential for consumer exposure to BHA by ingestion and dermal
contact is widespread. In 1975, the estimated average daily intake of
BHA in the diet was 4.3 mg (IARC 1986). It is a widely used food
additive in products containing vegetable oils or animal fats. It retains
its antioxidant properties even at high temperatures. The general
population may be exposed to BHA in butter, lard, meats, cereals,
baked goods, sweets, beer, vegetable oils, potato chips, snack foods,
nuts, dehydrated potatoes, flavoring agents, sausage, poultry and meat
products, dry mixes for beverages and desserts, glazed fruits, chewing
gum, active dry yeast, defoaming agents for beet sugar and yeast, and
emulsion stabilizers for shortenings. The estimated U.S. consumption
of BHA in food increased to 660,000 lb/yr during 1970 to 1982, up
from 374 lb/yr in 1960 (Anonymous 1984, IARC 1986). Reported
annual consumption for BHA in the mid 1970s was 990,000 lb
compared with 3.1 million lb for butylated hydroxytoluene (BHT)
(Kirk-Othmer 1978). Industrial use of BHA has largely been replaced
by tert-butylhydroquinone (TBHQ) (Kirk-Othmer 1980).
Theoretical and experimental.
studies have revealed that at microwave frequencies, geometrical
resonances occur in the mammalian brain that are manifested in non-uniform
distributions of absorbed energy which, for example, may result in maximum
absorption at the anterior hypothalamus, the thermoregulatory center of the
brain. Evidence derived from neurophysiological studies suggests that a
0 temperature rise of 0.01 C could result in a 3% alteration in the firing rate
of thermosensitive neurons of the preoptic nucleus of the hypothalamus.
Consequently, low-level microwave heating of such neural elements could conceivably
induce thermocompensatory responses which would be detected as an
alteration in the physiological status of the experimental subject. Such
effects would be dependent upon microwave-specific thermal changes. The
validity of this concept is dependent upon the creation of non-uniform temperature
distributions within the brain due to non-uniform energy absorption.
Since the brain is a vascularized organ, conductive cooling by blood circulation
would act to reduce non-uniform temperature distributions.
Experimental studies have been conducted at various frequencies ranging
from extra low frequencies (ELF) to microwave electromagnetic field effects.
Tinney exposed isolated poikilothermic turtle hearts to 960 MHz
continuous wave (CW) fields. In opposition to the anticipated tachycardia
which results from generalized heating, microwave exposure in the range of
absorbed powers of 2-10 mW/g resulted in significant bradycardia. The authors
hypothesize that microwave radiation causes neurotransmitter release by excitation
of the nerve remnants in the heart. Atropine, a blocker of the
parasympathetic system, and propranol hydrochloride, a sympathetic system
blocking agent, resulted in a suppression of the microwave effect when added
to the isolated hearts. By administering the drugs separately, evidence was
obtained that microwave radiation affects neurotransmitter release; the mechanism
for the effect is, however, unknown.
In vivo studies of the effects of low intensity microwaves on neurotransmitter
release have also been reported. Syngajevskaja found that 0.5 mW/cm2 decimeter wave exposure produced a significant decrease in acetylcholinesterase (Ache) activity in rabbit brains. An increase in acetylcholine and a decrease in Ache in the blood of irradiated animals has also been reported.
Repeated exposure of rats to 3 GHz microwaves at intensities
of from 10 to 40 mW/cm2 led to an initial increase followed by a
decrease in Ache blood activity.
Similar results were reported by
Baranski following irradiations of rabbits for two and one half to five
months, whereas an eight month exposure at an intensity of 1 mW/cm2 was
without effect. Three hour exposures of guinea pigs to 3 GHz CW radiation
at intensities of 3.5 and 25 mW/cm2 had no effect on Ache brain activity,
wnereas pulsed wave (PW) exposures caused a significant decrease in activity.
Repeated exposures resulted in increases in Ache activity, the effect being
more pronounced following pulsed field exposures. Ache activity in
rabbits repeatedly exposed to CW and PW microwaves for four months was found
to decrease in the case of CW exposure and increase as a result of PW irradiation.
The midbrain regions were found to be most affected. Microwaveinduced
alterations in lipid and nucleo-protein metabolism in the brains of
experimental animals have also been reported, the alterations again being
more pronounced following pulsed field exposure.
Merritt compared the effects of 1.6 GHz microwave and nonradiation
heating on neurotransmitter concentrations in the rat brain. Rats exposed for ten minutes to 80 mW/cm experienced a 4 C rise in rectal temperature
as did thermal controls exposed to elevated environmental temperatures.
Hypothalamic norepinephrine decreased in irradiated and hyperthermal control
animals compared to normothermal controls. Serotonin concentrations were
decreased in the hippocampal regions of irradiated rats but not in hyperthermal
controls. Similar results were obtained for the dopamine concentrations
in the corpus striatum and hypothalamus. Thermographic analyses of
the absorbed microwave power distributions indicated that the neurotransmitter
alterations were the result of microwave-induced hyperthermia.
Histological effects of low-intensity microwave exposure have been reported
by Albert and DeSantis. Chinese hamsters were irradiated with 1.7- 2
GHz CW microwaves at power densities of 10 and 25 mW/cm. Exposure for
thirty minutes to two hours induced cytopathology in hypothalamic and subthalamic
neurons.
Modulated low intensity electromagnetic fields have been reported to
alter calcium binding in cerebral tissue. Bawin and Adey25 exposed isolated
chick and cat cerebral tissues for twenty minutes to 0.05, 0.1, 0.56 and
1.0 V/cm fields at frequencies of 1, 6, 16, 32, or 75 Hz. A biphasic respouse
of Ca2 + in brain tissue was detected with a maximum suppression of
Ca2+ efflux occurring at 6 and 16 Hz and for field strengths of 0.10 and
0.56 V/cm. As in the case of alteration in heart rate reported by Tinney,
et aZ 16 , these results suggest the existence of a biphasic field strength
dependence since increasing the field strength to magnitudes greater than
0.56 V/cm reduced the treatment effect. Direct cortical stimulation of the
intact cat brain with 200 Hz, 10 msec pulses at intensities of 20-50 mV/cm,
on the other hand, resulted in a 20% increase in ca2+ efflux26 • Radiofrequency
fields with a carrier wave frequency of 147 MHz, amplitude modulated
at 6, 9, 11, and 16 Hz produced a statistically significant increase27
in ca2+ efflux from isolated chick forebrain at intensities of 1 to 2 mW/cm2•
A possible mechanism for the effect of low intensity radiofrequency radiation
on ca2+ efflux is suggested by the authors. They state17 that the
electrochemical equilibrium that exists in cerebral tissues between ions,
polyanionic macromolecules, and glycoproteins of the cell surface may be
disrupted by small variations of either the surrounding ionic concentrations
or local electrical gradients. Modulations of the radiofrequency field, reflected
as slow modulations of the extracellular electric field could thus
affect the Ca 2+ binding to the neuronal membrane. The fact that no effect
on Ca 2+ fluxes was produced by unmodulated fields and that a pulse repetition
rate dependent maximum rate of efflux was detected at rates of 11 and
2+ 16 Hz indicates that Ca movement was critically related to specific slow
components of the radiation field. They draw attention to the fact that this
frequency effect is consistent with results of other studies using various
electrophysiological endpoints and that it supports the finding that specific
modulation effects are involved in the reported induction of EEG changes in
the cat.
Bawin and Adev in discussing the inverse relationship of ca2+ binding
effects in neural tissue in response to modulated VHF and ELF fields indicate
that the results suggest field interaction with a common substrate which
is dependent on the interaction energy provided by the field. The basis for
the amplitude selectivity or biphasic amplitud~ response of ca2+ binding is
suggested as being related to the mode of Ca 2+ binding to neuronal biomolecules
which may consist of strong or weak bonding depending upon sitespecific
molecular binding sites2'. The authors state that no completely satisfactory explanation can be given ~or the biphasJc frequency response;
\they note that subjective time estimates in monkeys'are speeded up in the
presence of a 7 Hz, 0.10 V/cm sinusoidal field but in order to induce this
effect at 45 to 75 Hz larger field strengths are required. Bawin and Adey'
also state that EEG patterns in the cat are reinforced by VHF fields amr
plitude modulated at the dominant EEG frequencies but not by CW fields or
fields modulated at other frequencies. It is suggested that the frequency
specificity of the responses is an indication of a direct field effect on
the CNS, rather than a more generalized peripheral transduction.
It is indicated that the current density induced by a 10 mW/cm2
microwave field is 1000 times greater than the polarizing current densities required to produce an alteration in the firing patterns of ganglia.
Servantie, et aZ 32 studied the synchronization of cortical neurons in the rat by pulsed 3 GHz radiation at an average intensity of 5 mW/cm and a pulse repetition rate of 500-600 Hz. Experimental animals were exposed in free space conditions for ten days after which occipital EEG's were recorded.
The exposure resulted in the induction of an electrocortical frequency synchronous
with the microwave pulse modulation frequency. The induced electrocortical
frequency, which is significantly higher than those generally recorded,
persisted for a period of hours following the termination of exposure.
Thomas, et aZ 36 as previously
noted, found that exposure of rats to low intensity 5 mW/cm2
pulse modulated microwaves altered the animal's ability to judge the passage
of time, a result previously reported by Justesen 3 ~ in the same species.
Thomas and coworkers~ 0 have recently reported that PW 2.45 GHz microwaves at
5, 10, or 15 mW/cm 2 caused a dose-dependent increase in the frequency of premature
switching in a fixed consecutive-number schedule in rats following
thirty minute exposures, suggesting an alteration in time perception. Using
a markedly lower radiation frequency, Gavalas-Medici and Day~ 1 found exposure
of rhesus monkeys to 7 or 75 Hz fields at field strengths as low as 0.10 V/cm
caused a reduction in interresponse times in agreement with the results of an
earlier study employing a 0.07 V/cm, 7Hz field~ 2 • At a field strength of
0.56 V/cm interresponse times were significantly shorter for both 7 and 75 H?
fields and the differences were almost three times greater than at a field
strength of 0.10 V/cm. Another indication of an alteration in the "biological
clock" was reported by Bliss and Heppner~ 3 who used a different temporally dependent
endpoint, a different species, and a different type of exposure. They
investigated the effects of exposure to a zero magnetic field on the entrainment
of the circadian activity rhythm of the House Sparrow, Passer domesticus.
Periodogram analysis showed that the activity period lengths of control birds
were longer than the experimental birds. Midpoints of activity time were significantly
later for controls than for experimentals.
Studies of the interaction of microwave radiation and various drugs that
affect the mammalian CNS have also yielded evidence of the sensitivity of
neural elements to low field intensities. Goldstein and Sisko~~ and Cleary
and Wangemann~ 5 detected alterations in the response of rabbits to anesthesia
as a result of low intensity CW microwaves at 9.3 and 2.45 GHz respectively.
Baranski and Edelwejn~ 6 investigated microwave-drug interactions in
rabbits given CNS stimulants or depressants. Chloropromazine induced rapid
synchronization of previously desynchronized EEG patterns which led the
authors to conclude that there was an antagonistic interaction of microwaves
withthis drug which most likely occurred in the activating part of thereticular
formation and the cerebral cortex~ 6 • Servantie, et al~ 7 also found
that the susceptibility of mice to the effects of certain drugs was significantly
altered by exposure to pulse modulated 3 GHz microwaves at an average
intensity of 5 mW/cm2.
Altered drug tolerance in humans occupationally exposed to microwaves
has also been reported by Edelwejn and Baranski~ 5 • Intravenous injection of
cardiazole (Metrazol), a drug which acts on the human CNS, did not induce any
effects in normal adult males at a dosage level of 7 mg/kg body weight. However,
the drug produced alterations in EEG patterns (theta waves, theta discharges
and spike discharges) in microwave workers with over three years of
exposure; convulsions occurred forcing the abandonment of the study as being
hazardous to the patients. A marked decrease incardiazole tolerance has also
been demonstrated in microwave exposed rabbits.
Evidence has also been reported that occupational microwave exposure
leads to alterations in human CNS function. The effects, many of which are of
a subjective nature such as headaches and fatigue, reportedly occur during
the first three months of employment and then recur after another three to
four months. After one year of occupational exposure, the symptoms appear to
remit for various lengths of time, suggested as being due to an adaptive .
response, but objective symptoms of various neurovegetative disturbances recur
after approKimately five years of exposure 50
• The chronic overexposure syndrome
in humans is characterized by the occurrence of headaches, irritability,
sleep disturbances, weakness, decrease in libido, chest pains, and generalized
psycho-physiological depression.
The adaptive response of rats to microwave exposure following irradiation
with 2.86 - 2.88 GHz CW microwaves at intensities between 10 to 120
mW/cm2 was illustrated by the experiments of Mikolajczyk.
The survival time of hypophysectomized rats exposed to 120 mW/cm2 fields was increased
relative to unoperated animals.
Alterations in carbohydrate metabolism, a possible indirect neuroendocrine effect of microwave exposure, were induced by exposure of rabbits to 3 GHz CW fields at 5 mW/cm2.
Low intensity microwave exposures,
which would involve low level gradual heating, would be expected to
result in a generalized suppression of neuroendocrine response as reflected
in metabolic suppression.
Although data on the human response to low-level
microwave exposure is very limited, the reported decrease in thyroid function
in chronically exposed workers is consistent with this hypothesis.
A rather consistent finding has been that
microwave exposure causes transient lymphocytosis and leukocytosis. Erythrocytes
appear to exhibit a somewhat lower sensitivity to exposure effects,
with some suggestion of an exposure dependent decrease in erythrocyte
production.
Alterations in nuclear structure and in the mitotic activity
of erythroblasts, bone marrow cells, and lymphatic cells in both lymph nodes
and spleen in guinea pigs and rats following prolonged exposures to 3 GHz microwaves at an intensity of 3.5 mW/cm have been reported by Baranski.
Low intensity (3 mW/cm2) exposures at 2.95 GHz for periods of one to three
months altered the circadian rhythms in hematopoietic cell mitosis in rabbits.
Repeated daily exposures of mice and rabbits to 0.5 and 5 mW/cm
intensities respectively, to 2.95 GHz microwaves for periods of up to six
months, resulted in an increase in lymphoblasts in lymph nodes and in lymphoblastoid
transformations during the first two months of exposure and for one
month post-exposure, an effect which Czerski68 indicates to be uniquely related
to microwave exposure.
The mobilization of bone marrow granulocyte reserve pools
in response to six weeks of exposure at 3 mW/cm2 , as well as a reduction in
lysozyme activity in the blood, has been reported by Szmigielski69 • Microwave
exposure has also been reported to increase the number of colony forming units
(CFU) in the bone marrow and spleen of mice following a five minute exposure
to 2.45 GHz CW microwaves at an intensity of 100 mW/cm2, evidence of an induced
transition of hematopoietic stem cells from a resting to an active state.
The obvious problem encountered in the establishment of causal relationships
for low intensity microwave-induced alterations in biological systems is
the lack of physical interaction mechanisms to explain such phenomena. In
spite of the fact that a number of hypothetical mechanisms, such as fieldinduced
alterations in macromolecular hydrogen bonding, proton tunneling and
disruption of bound water, have been suggested, no theoretical or experimental
basis has been established for the occurrence of such mechanisms in either in
vivo or in vitro biological systems. It may be concluded that since the energy
of a microwave photon is far smaller than the activation energies estimated
for such effects, quantized frequency-specific microwave absorption would not
appear to be a feasible mode of interaction.
This conclusion, however, must be qualified due to the fact that the activation energies are by and large based on estimates derived from in vitro molecular studies rather than in
vivo systems in which high potential energy states are known to exist that
could markedly alter activation energies for the above mentioned phenomena.
Relatively weak interactions or secondary forces are responsible for
the molecular conformation as well as for the stabilization of macromolecular
complexes such as biomembranes. In view of the fact that many biomolecular
functions are dependent upon precise steric interactions, the integrity of
the noncovalent secondary bonding is essential for biological function. Such
secondary forces, including hydrophobic interactions, hydrogen bonds, and
London-van der Waals interactions, correspond generally to significantly
lower energies than covalent bonding. Although the actual energies associated
with secondary bonding in in vivo systems are not known, the potentially
low magnitude of such forces in cooperatively bonded in vivo macromolecular
assemblages suggest that such systems could be subject to perturbation by low
intensity microwave or radiofrequency fields.
The most well-characterized interaction mechanism of alternating electromagnetic
fields with biomolecules is field-induced rotation, Polar molecules,
such as proteins or water, exhibit dielectric relaxation w~th frequency dispersions
that are dependent upon molecular parameters such as size, shape,
molecular weight, and dipole moment. Characteristic frequencies, the moleculespecific
frequencies of maximum energy exchange with impressed fields, are in
the region of 1 to 10 MHz for proteins in aqueous solution, and in the 20 GHz
region for free water. A particular dispersion, referred to as the 8 dispersion,
which has been detected in the 0.1 to 1 GHz regions, is attributed to
either field-induced rotation of protein polar sidechains or the rotation of
bound water. Although dielectric relaxation of proteins and other biomolecules
has been extensively investigated, whether or not this type of interaction results
in functional alterations in living systems has not been determined. On
the basis of data derived from in vitro dielectric dispersion studies of proteins,
it appears that microwave or radiofrequency intensities of 10 mW/cm 2
or greater would be required for dielectric relaxation in living systems, although
there is much uncertainty in this estimate 72 • It is thus difficult, in
view of the pa~city of the available information, to determine the role of
dielectric relaxation in low intensity microwave or radiofrequency effects on
biological systems.
Rotation of water is characteristic of dielectric dispersion of small
polar molecules and even the polar side chain of larger molecules such as proteins.
Thus, Pennock and Schwan 3 determined that dispersion in hemoglobin
solution between 50 and 100 MHz was due to rotation of polar side chains. The
dispersion in the regions between 1 MHz and 100 MHz is further complicated by
the finding5 that there exists an additional dispersion due to the induced dipole
moment of the protein backbone which has a dielectric constant greater
than 20. Other large macromolecular constituents of the cell may also be expected
to have such induced dipole moments. Finally, the helix-coil transition
in proteins also has a relaxation in this region sometimes called the
"chemical" relation6 • Such dispersions due to conformational transitions may
contribute little to the overall dielectric constant even at their maximum
dispersion; however, conformational transition induced by electromagnetic radiation
may have functional effects, although the displacement from the already
rapid transitions due to thermal agitation is quite small.
At lower frequencies, larger cellular structures become responsible for
dispersion. In the 8 region, Schwan7 has attributed the dispersion to the
change in polarization which occurs at the boundary of phases of different dielectric
constant, the so-called Maxwell-Wagner effect. In the cell, the most
likely boundary is the cell membrane where a lipid-water transition occurs.
Such an interpretation was further verified using the dielectric dispersion of
yeast at 100 KHz. Upon treatment with cetyl trimethyl ammonium bromide, a
detergent which disrupts the cell membrane, the 100 KHz dispersion disappeared.
Most tissues and cells exhibit a strong dispersion in the a region at
100 Hz and below, with the apparent dielectric constants increasing to very
large values, with even DNA having a dielectric constant of 240-340 at 100 Hz 9 •
At least part of the dispersion at these low frequencies can be ascribed to
movement of ionic countercharges in the fixed charge latticework of large
assemblies of macromolecules such as bacterial cell walls; the same dispersion
can be seen in ionic exchange resins.
While the bulk dielectric constants of living matter can be fairly well
understood by the foregoing discussion, other more highly specific absorptions
of electromagnetic radiation may be important but not be observable against
the background of strong absorption by the more non-specific mechanisms.
It was pointed out by Lowdin several years ago that the DNA double
helix formed by complementary hydrogen-bonded base pairs could have the position
of the proton shifted from one nucleic acid to its complementary neighbor
by a tunneling process. Subsequent replication of the sequence would then
yield a complete alteration of the base pair from A-T to G-C or vice versa.
In the same paper11 , the author suggested that such a tunneling process might
be induced by electromagnetic radiation of the proper frequency. No experimental
evidence of such assisted tunneling in DNA has yet been reported. However,
it is interesting to note that recent experiments indicate that at
low temperatures (< 25°K) carbon monoxide can tunnel to form a ligand in heme
proteins. The possibility of tunneling of large atomic masses such as CO and
assistance by electromagnetic radiation at lower frequencies bears further
investigation.
The highly oriented assemblies of macromolecules which make up functioning
units of the cell such as ribosomes or mitochondria depend on correct
positioning of neighboring molecules for sequential reactions. The induction
of rotation of one or more molecules within such an assembly might disrupt
function transiently or permanently if the rotation is to a new stable
position. No experimental evidence is available concerning such rotation,
but measurements of the functioning of the assembly would probably be much
more sensitive to such an effect than measurements of dielectric constant.
Another possible interaction of electromagnetic fields in living cells
might occur by bringing into forced oscillations "gating" molecules which
are postulated to control ionic conductivity in excitable membranes.
Armstrong and Bezanilla 1 ~ have attributed the frequency dependent capacitance
of squid axons to these gating molecules 15 • Polarization currents
dependent on membrane potential in muscle membrane are also thought to be
due to gating molecules with large permanent dipole moments 16
While single peak-to-peak amplitude of external a-c fields would need to be large to
cause the gate molecules to undergo a transition, much smaller amplitudes
could cause transitions over a period of time if the gating molecules were
brought into gradually increasing forced oscillations.
Whatever the mechanisms of absorption of electromagnetic radiation,
the energy absorbed must be dissipated and thermalized. The rate and pathways
of thermalization of absorbed energy in the living system have been
little explored. Recent studies 17using laser enhanced chemical reactions
in the gas phase, have indicated that equipartition of electronic energy
into vibrational modes is not immediate but may take as long as 10-5sec.
Such slow distribution of energy allows time for enhanced reactivity of one
particular vibrational mode 18• If such unexpected delays in reaching thermal
equilibrium occur in rotational and translational excitations, enhanced
reaction rates might be observed in living systems excited by electromagnetic
radiation of comparatively low frequencies.
Barriers to thermalization might well be cellular structures with low
thermal conductivity such as the cell membrane. As a consequence of electromagnetic
radiation absorption within a relatively thermally isolated volume,
energy dissipation would be slowed enough so that temperature rise would
occur in that volume. At least in one model membrane system, detergent
vesicles, temperature rise was seen to occur and persist after visible light excitation of a dye within the vesicles.Highly localized temperature
elevations due to thermal barriers might then cause susceptible proteins to denature even if the temperature elevation is not more than 8-10 C. Some
denaturations of proteins can occur over very narrow temperature ranges.
In addition, temperature dependent phase transitions in lipid membranes
can be induced over the entire physiological range. In several membranebound
enzyme systems the transition of the lipid phase is accompanied by
functional changes in certain membrane-bound enzyme activity.
Because of the thickness of the cell membranes (-100 A), even a small
absolute difference in temperature between two sides of the membrane results
in a large thermal gr~dient across the cell membrane. Such thermal gradients
can be coupled to flow of solutes and solvents known as the LudwigSoret
effect. The phenomenological equation can be written in terms of nonequilibrium
thermodynamics 23 • In cell membranes, the thermal diffusion coefficient
is undetermined but with large thermal gradients both ionic and
osmotic gradients could be established.
These and related studies further imply that:
(a) the refinement of theoretical biophysical models beyond the heuristic
state now extant, and (b) their test and refinement via millimeter wave and
far infrared spectroscopy of biological materials may serve to elucidate
fundamental aspects of biophysics, including enzyme selectivity and catalysis,
coding of cellular differentiation, and aspects of neurological
function.
As Frohlich24 suggests, the raison d'etre, in an evolutionary sense,
for the extraordinarily high intrinsic electric fields in biological membranes
(- 10 5 V/cm) may be the establishment of the resultant unusual dielectric
properties of in situ biomolecular systems which, via collective behavior,
permit biological systems to perform tasks (such as information acquisition
and discrimination in the ubiquitous presence of inherent thermal noise) and
whose sophistication may border on the limits set by quantum-mechanical principles.
In this connection, the extent to which quasi-resonant interactions
between coherent electromagnetic fields and biological systems may be operative
in the millimeter wave and far infrared region is of crucial importance
to the question of the existence of bioeffects.
Qualitatively, while theprediction, on the basis of the Debye model, of a constant (asymptotic)
attenuation distance for H20 in the millimeter wave region and the low frequency
portion of the far infrared region is correct, it is expected that
there may exist a window (relatively large attenuation distance) between the
broad rotational relaxation spectrum in the millimeter wave and far infrared
region and the discrete, resonant (intramolecular-vibrational) transitions in
the infrared region. An additional complication arises from the existence of
translational and librational quasi-lattice modes in liquid H20 in the far
infrared region 10 • Inasmuch as the relaxation absorption spectrum of free
H20 serves as an efficient attenuator of millimeter wave and low-frequency
far infrared radiation (the attenuation distance, [a(w)]- 1 ),is of the order
of 10-2 em in the 10- 1 em wavelength range, and since, in contrast, this constant
attenuation due to the relaxation regime cannot persist in the highfrequency
limit, an accurate characterization of this contribution to a(w)
over the entire range in which (quasi-resonant) coherent oscillations may be
expected to occur, is of considerable interest. Fig. (3) represents a(w)
for the relaxation spectrum of free H20 as computed from the collisionalperturbation model.
Structural H20 is a salient entity in the stabilization of conformational
structures of biopolymers in general , and appears to be a crucialcomponent in the formation of metastable states associated, in particular,
with coherent electromagnetic oscillations. As a component in the free-H20-structural-
H20 mixture, the latter contributes a broad relaxation regime
absorption, with a maximum value for x"(w) at a frequency inte~diate to the
corresponding critical frequencies for free liquid H20 and ice.
In the extreme of highly efficient interconversion,
the strongly selective intervention of external electromagnetic
radiation, in the region below 10 GHz, into the properties of structural
H20, would be unlikely. However, the actual efficiency of this intercoversion,
as a function of T, and, in particular, any resulting biologically important
selectivity, is as yet an unresolved question.
A number of studies indicate that cannabinoids
impair memory acquisition in mammals by suppressing
excitation in the hippocampus, one consequence
of which is that hippocampal neural activity remains
below levels required for long-term potentiation
(LTP; Terranova et al., 1995; Stella et al., 1997;
Hampson and Deadwyler, 2000; Sullivan; 2000). That
is, activation of CB1 receptors impairs LTP via inhibition
of presynaptic calcium channels, thereby reducing
excitatory neurotransmitter release below levels
that are required to remove the magnesium block from
postsynaptic NMDA receptors (Misner and Sullivan,
1999; Sullivan, 1999; Hoffman and Lupica, 2000).
Prior work has shown that cannabinoid exposure of zebra finches during sensorimotor stages of vocal development alters song patterns produced in adulthood. We are currently working to identify physiological substrates for this altered song learning. FoxP2 is a transcription factor associated with altered vocal development in both zebra finches and humans. This protein shows a distinct pattern of expression within Area X of striatum that coincides with peak expression of CB1 cannabinoid receptors during sensorimotor learning. Coincident expression in a brain region essential for song learning led us to test for a potential signaling interaction. We have found that cannabinoid agonists acutely increase expression of FoxP2 throughout striatum. When administered during sensorimotor song learning, cannabinoids increase basal levels of striatal FoxP2 expression in adulthood. Thus, song-altering cannabinoid treatments are associated with persistent increases in basal expression of FoxP2 in zebra finch striatum.
Vocal learning and production
in zebra finches is associated with marked physiological
changes within distinct regions of telencephalon (e.g.
lMAN, Area X, auditory Field L2, RA) and thalamus
(DLM, ovoidalis) known to be critical for song perception,
production and learning. Each of these regions distinctly
and densely expresses CB1 receptors [3]. Normal
development in song regions is associated with gross
anatomical changes in region volume, neuron number
and density, both increases and decreases in axonal
interconnections between song regions, and changes in
synaptic densities. Cannabinoid-altered vocal development
implies that exogenous agonist exposure must
somehow alter some or all of these processes responsible
for critical periods of song learning. We are currently
working to identify which processes are modified by
developmental cannabinoid exposure and the mechanism
(s) responsible.
Indeed, Grant~ 9 hasdirected attention to the potential role of structural H20 as principal absorber
(via its relaxation spectrum) in the low-frequency portion of the relaxation
spectrum of free H20 below - 10 GHz. In addition, in view of the
role that structural H20 plays in the establishment and stabilization of the
metastable state, selective interactions involving structural H20 in the millimeter
wave and far infrared region would appear to be possible.
Considerable controversy exists as yet concerning the equilibria and
dynamics of H20 molecules in general cellular systems, particularly, with respect
to the proportion of free H2 and structural H20. In part, this arises
from the ambiguities inherent in the analyses of relaxation dynamics of
rotationally- and irrotationally-bound and (rotationally and translationally)
free H20 from proton magnetic resonance spectroscopy • e attenuation
function for structural H20 has been characterized~'~ 2 to --30 GHz,
but no experimental data is available in the millimeter wave and far infrared
region. As indicated, structural H20 is considered to be an indispensible
building block in the system associated with the long-range collective interactions
and the coherent electromagnetic oscillations.
Conversely, if such controlled (beneficial) biomedical applications
were possible, it is requisite to inquire into possible bioeffects and health
implications of technological electromagnetic radiation in the coherent regime
frequency region. In point of fact, several technological applications must
be considered in this context: (a) multichannel millimeter wave communications
systems [waveguide and open transmission systems], (b) millimeter wave
high-resolution radar, and (c) microwave power transmission, along terrestrial
and proposed satellite-based transmission routes throuph the earth's
I
atmosphere 58 ' 59 • In connection with these existing and proposed man-made
electromagnetic radiation fields, one may ask the general question concerning
the coupling of electromagnetic radiation with the entire biophysical
model envisaged by Frohlich24 ' 29 , encompassing the coherent regime oscillations
associated with the metastable state and the coupled ELF oscillations
arising from the oscillatory biochemical reactions. Fig. (5) provides a
schematic view of components of these systems. On the basis of current evidence,
and the (as yet incomplete) understanding of underlying biophysical
mechanisms, one may speculate along the following lines concerning external
electromagnetic field interactions with this system. Three possible leverage
points for perturbation may be identified: (a) the membrane intrinsic electric
field, which is responsible for setting up the metastable state(s), (b)
the coherent regime frequency branch in the - 10-10+3 GHz region, which is
associated with the long range molecular interactions, leading to the coupled
biochemical reactions, and (c) the resulting ELF frequency branch in the
-10-100 Hz region.Thermal fluctuations cause time-variant electromagnetic
fields, with a vanishing time average, and may superimpose on the average
membrane intrinsic field, and cause occasional sporadic nerve impulses~ 9 • In
a system close to the triggering threshold, at a given instant in time, an
external field may, in principle, add to the fields caused by thermal fluctuations
and lead to sporadic impulses 60 • However, strong intervention in the
average membrane field, and hence significant perturbations of its time average
properties by external fields is not predicted except for very high (static)
field strengths, close to the dielectric breakdown of bulk tissue. Intervention
in the ELF branch <~ 10-100 Hz) of the cooperative system by external
fields is probably weak, while coupling with coherent electromagnetic radiation
in the coherent regime branch <~ 10-1000 GHz) may occur. This (highly
tentative) analysis appears to be in harmony with the type of (unperturbed)
environmental terrestrial electromagnetic fields 5 that exist, if one may
assume that evolutionary development would emerge in a fashion (for a pervasive
biophysical system) so as to minimize coupling with the unperturbed environment
and optimize the operation of the biophysical system and associated
biological function. While atmospheric electric fields in the ELF region are
prevalent and may reach substantial field strengths, the millimeter wave
region of the terrestrial background electromagnetic field is a quiet zone,
contributed to only by the (extremely low field strength) low frequency tail
of terrestrial blackbody radiation, which peaks in the infrared region, and
the (extremely low field strength) contribution of the cosmic millimeter wave
blackbody radiation arising from the (drastically red-shifted) electromagnetic
pulse attendant to the initial phase of the formation of the universe.
in DNA there are some water molecules
which are hydrogen-bonded to the biopolymer itself; the water molecule is in
the framework of the biopolymer. That is certainly different from water
molecules which are hydrogen-bonded to the cells. The efficiency of the interconversion
of rotational relaxation of the two types of water must be far
different.
We are referring to an assembly of biopolymers within the membrane
intrinsic field which produce oscillations which are coherent electromagnetically.
The sources of the intrinsic oscillations are vibrations. The whole
theory has a formal resemblance to the Einstein condensation of a gas.
Frohlich suggests that the frequencies may be as low as 10 gigahertz and may
go up into the hundred or thousand gigahertz region.
Since 1975, evidence has accumulated that the binding and release of
calcium in brain tissue involves processes radically different from simple
equilibrium states 1
• Calcium ions are essential in the release of transmitter
substances from presynaptic nerve terminals and in transductive
coupling of immunological, endocrine and neurophysiogical stimuli at the
membrane surface, as well as in ensuing transmembrane coupling. This new
evidence suggests that for cerebral tissue, at least, it may be necessary
to substantially revise generally accepted views on the structural and functional
basis of excitation, particularly in regard to the role of weak electrical
gradients in the immediate environment of brain cells.
The response of cerebral tissue to certain low level oscillating environmental
electromagnetic fields is anomalous in that a sharply modified
release of calcium has been found only in a narrow range of frequencies
between 6 and 20 Hz. Responses also occur with radiofrequency fields amplitude
modulated in the same narrow range of low frequencies, but are qualitatively
different. The second quite unexpected finding is that these sensitivities
occur only within a range of field strength or a power window. The
appearance of sharp upper and lower field intensity thresholds distinguishes
these findings from what is expected of chemical reactions in simple equilibrium
systems.
The data strongly suggest that the binding and release of calcium occurs
cooperatively as the result of long-range interactions between anionic charge
sites on the binding substrate. A striking aspect of these studies has been
the consistent occurrence of major shifts in calcium efflux (in excess of 10
per cent) with fields that produce very small gradients in the extracellular
space surrounding cell membranes. The extracellular fields are about 10- 7V /cm
and 10- 3V /cm for the low frequency and modulated radio frequency experiments
respectively. They are thus far below transmembrane gradients of 10 3V /cm
associated with a typical synaptic depolarization. Moreover, the gradients
induced in the extracellular space along the membrane surface would be about
76
10 3 times larger than any transmembrane components of the same field, because
-1
the low specific resistance of extracellular fluid, about 4 ohm-em , shunts
a current around the membrane, which has a transmembrane resistance of about
2 5,000 ohms/em •
Thus, on biophysical grounds alone, large shifts in calcium efflux induced
by the imposed fields would be expected to occur primarily in the extracellular
fluid and at cell membrane surfaces. This a priori consideration
fits well with the huge differences in calcium concentration between the
extracellular space and the general cytoplasm of the cell. Typically, calcium
concentration in cerebral extracellular space is 2.4 mM; within the
cytoplasm, it is around 10- 8M . Organelles, such as mitochondria, which have
much higher concentrations 2 , may not participate in the dynamic exchanges
associated with membrane excitation.
FREQUENCY AND POWER WINDOWS IN SENSITIVITY
OF CEREBRAL TISSUE TO OSCILLATING EM FIELDS
Extremely low frequency (ELF) sinusoidal fields from 1 to 75 Hz have
been tested for effects on calcium efflux from freshly isolated neonate chick
cerebral hemisphere and cat cerebral cortex~. Electric gradients in air
ranged from 0. 05 to 1. 0 V/ em. Tissue gradients could not be measured, but were
estimated to be of the order of 0.1 ~V/cm. Both frequency and amplitude
sensitivities were observed. A decrease in calcium efflux of 12 to 15 per cent
occurred at frequencies of 6 and 16 Hz. For chick tissue, the field threshold
in air for this response was around 0.1 V/cm, and for cat cortex around
0.6 V/cm. At intensities above or below these levels, trends towards a decreased
efflux that were not statistically significant were observed (Fig. 1).
Studies with very high frequency (VHF), 147 MHz, radio fields, amplitude
modulated in the same low frequency band (0.5 to 35Hz), also produced shifts
in calcium efflux from chick cerebral tissue 5
• At modulation frequencies from
6 to 20 Hz, there was a significant increase in calcium efflux, reaching a
maximum of more than 15 per cent, and following a smooth "tuning curve" over
this range.
It should be noted
that the increased efflux observed with these 147 MHz fields mirrors the curve
for decreased efflux produced by ELF fields. This point is discussed below,
although no adequate biophysical or structural model can be offered at this time. Fields were maintained constant at 0.8 mW/cm in these studies. Tissue
gradients were not measured, but would be expected to be about 10 mV/cm, a
value consistent with actual measurements at 450 MHz described below.
The cell membrane has long been described in terms of a lipid bilayer.
With the progression from light to electron microscopy, the membrane became
identified with the plasma membrane in standard electron micrographs. It is
now known8 that the plasma membrane is part of a much broader bounding
structure, the "greater membrane". In this model, there are macromolecular
lamellae on .the outer and inner surfaces of the bilayer. In part, at least,
these covering macromolecules are protrusions from intramembranous particles
(IMP) that lie within the bilayer. This complex organization and its possible
significance in transductive coupling of weak electrical and chemical
stimuli has been reviewed elsewhere.
COHERENT STATES OF FIXED CHARGES ALONG THE MEMBRANE SURFACE
Singer and Nicolson9 have extended the greater membrane concept in the
"fluid mosaic" model, emphasizing the lateral mobility of certain IMPs within
the lipid layers. These protruding terminals of protein molecules are composed
of sugar molecules. They are acidic and have numerous negative charge
sites. The surface formed by these negatively charged binding sites constitute
a polyanionic sheet. From studies of biopolymer sheets, including
poly-1-glutamic acid, Schwarz 10 ' 11 concluded that these charges may behave
coherently, with adjacent elements having the same energy levels. A coherent
domain of anionic fixed surface charge sites at the membrane surface requires
energy to raise them above the ground state. In some membrane surface phenomena,
energy is supplied by metabolic processes, as in the immunological
"patching" reaction at the surface of lymphocytes. There is as yet no precise
knowledge about sources of energy that might contribute to coherent
surface charge states.
Implicit in the concept of a coherent domain is the expectation that for
the duration of the coherent state, this patch of membrane surface would be
thermally "quiet", that is, isolated from the randomization of energy levels
which is characteristic of the non-coherent condition. Such a system could
be restored to the ground state by an extremely weak trigger, at the level of
thermal noise or below. The action of a weak trigger at one point in a coherent
system resulting in an effect at a remote site elicits a far greater
release of energy than the trigger itself.There is an avalanche or domino
effect, best expressed in the term "quantum amplification".
COOPERATIVE PROCESSES BETWEEN SURFACE FIXED CHARGES
Cooperative processes occur, or are suspected to occur, in a variety of
biological systems. For example, a single photon of visible light with an
energy of 0.6 eV produces a perception of light. Its absorption by the disc
within a retinal receptor causes the release of about 1400 calcium ions,
which migrate outward to the receptor membrane.The triggering energy of
the single quantum is several orders of magnitude less than that required to
release these calcium ions from their binding sites.
For brain tissue, evidence from our electrom·agnetic field experiments
suggests that binding of calcium ions is highly sensitive to weak imposed
fields. A fully successful model must specify the location of the calcium
ions susceptible to the electromagnetic fields, and the competitive binding
of other cations (including the monovalent ions sodium, potassium and hydrogen)
to the same or adjacent sites on a suitable macromolecular, polyanionic substrate.
This first step is impeded because the binding energies for these
ions remain conjectural. For calcium, at least, binding may occur directly
to carboxyl groups, whereas a-sulfate groups offer a looser electrostatic
attraction through an atmosphere of water molecules.
In dielectric measurements over the spectrum from 10 MHz to 50 GHz water molecules close to macromolecular surfaces exhibit dielectric properties different from those of
molecules remotely located. These measurements show that it is no longer
possible to regard water as behaving uniformly throughout the extracellular
and intracellular compartments.
Electrophysiological evidence also supports the concept of interaction
between calcium and cell surface macromolecules in functional modulation of
the intercellular space. An apparent reduction in extracellular calcium concentration
by as much as 20 per cent occurs during cerebellar stimulation,
but measuring techniques would not distinguish between actual removal of
calcium from the extracellular space and an alteration in its state of binding
to surface polyanions. The latter explanation would appear more probable
with respect to the major part of the extracellular calcium. There is a
sharp increase in the electrical impedance of cerebral tissue associated with
increased extracellular calcium levels 15 • In these measurments, the major
part of the impedance measuring current travels in extracellular channels
The reciprocal contours of calcium efflux curves from cerebral tissue in
ELF and VHF/UHF field exposures suggest that calcium ions may be bound to
surface macromolecules in at least two different ways. As discussed elsewhere,
a plausible but so far untested explanation may lie in the concept of
strong attachment to single molecular strands and weaker bonding between
strands. These different modes of bonding might be amenable to manipulation
by the widely differing energies in weak ELF and much stronger radiofrequency
field interactions.
DIELECTRIC CHARACTERISTICS OF THE COUNTER ION LAYER
Micron diameter resin particles with porous surfaces have effective dielectric
constants as high as 10 6 at frequencies below 1KHz. The f indings
may be relevant to interactions of the numerous finer branches of cerebral
dendrites with surrounding electric fields. This model considers the case of
porous particles with a uniform volume distribution of fixed charges. The
boundary region is characterized by a very large, radially-directed static
field with a corresponding radial variation in the distribution of mobile
ions. The external electric field causes a polarization of the ionic atmosphere,
an effect that can be expressed by an additional "apparent" dielectric
constant of the particle, exceeding the actual dielectric constant by several
orders of magnitude at low frequencies. The magnitude of the low frequency
dielectric constant is proportional to the size of the particle and the square
root of the fixed charge concentration in the porous material.
As discussed elsewhere, this phenomenon at the surface of small particles
or tubes with diameters in the range of most branches of cerebral neuropil
suggests that ionic movements in oscillating electric fields close to such a
membrane surface may be severely attenuated except at very low frequencies.
This attenuation would apply to the transfer of thermoelectric noise. With
a specific resistance for brain tissue of 300 oh~cm and an effect~e frequency
bandwidth from 0 to 100 Hz, the equivalent noise voltage would be of
the order of 10-8 V/cm. This tentative model is of interest in view of observed
sensitivities of 10-8 V/cm in marine vertebrates and the behavioral
and neurochemical effects seen in birds and man and other primates attributable
to oscillating gradients less than an order of magnitude larger.
Preliminary models of membrane excitation based on quantum mechanical
aspects of cooperative charge interactions have been formulated by
Frohlich18- 20 • Frohlich has modeled long range coherence and energy storage
based on dipole interactions and the recurrence of certain bonds, such as
H-bonds, in macromolecules. High sensitivity of biological systems to weak
electromagnetic fields would then relate to a mechanism through which they
store energy, and in so doing, overcome thermal noise. Extremely high frequency
oscillations at 10 11 to 101 2 Hz would occur simultaneously with limitcycle
behavior at very low frequencies. Grodsky has considered the
membrane lipid bilayer as a sheet of dipoles under an electric strain attributable
both to the dipoles' mutual interactions and to the local electric
field generated by cations in the polyanionic glycoproteins of the outer
membrane. This system will respond to a surrounding electric field with a
change in long range order, a phase transition occurring over a narrow range
of fixed temperatures below a critical point (The Neel temperature). The
system will oscillate with most energy in a narrow low frequency band.
1. The effects of weak electromagnetic fields have been tested on the efflux
of calcium from cerebral tissue of chick and cat. The data strongly suggest
that the binding and release of calcium occurs cooperatively as the
result of long-range interactions between anionic charge sites on the
binding substrate.
2. Extremely low frequency (ELF) fields at frequencies of 6 and 12 Hz and
gradients in air of 0.1 to 0.5 V/cm decreased calcium efflux by 12 to 15
per cent. Higher and lower frequencies were without significant effect.
For chick tissue, the field threshold in air was 0.1 V/cm and for the cat
around o".6 V/m. At intensities above and below these levels, effects became
statistically insignificant.
3. With 147 MHz amplitude modulated fields, calcium afflux from chick cerebral
tissue increased for modulation frequencies from 6 to 20 Hz, with a
maximum of more than 15 per cent. No significant changes occurred at
hi£her or lower modulation frequencies, nor with an unmodulated carrier
wave.
4. With 450 MHz fields amplitude modulated at 16 Hz, increased calcium efflux
from chick cerebral tissue occurred at field intensities between 0.1 and
2 1.0 mW/cm • No increase was noted above or below these levels.
5. This series of amplitude and frequency windows is discussed in relation to
possible modes of cooperative organization of cell membrane surface glycoproteins
in the binding and release of calcium.
You indicate that these extremely long waves were in some way involved
in the transfer of information from the brain. It is well known that the
information that cane tPansmitted on a aarrieP signat is a function of the
fPequenay of the aarPieP signat. A aarPier signat in the t6 HePtz Pange aan
at most tPansmit onty a few bits peP seaond.
We examined cardiovascular responses to intravenous administration of anandamide and the synthetic cannabinoid, (WIN55212-2), in conscious male Wistar rats made acutely hypertensive by infusion of angiotensin II (AII) and arginine vasopressin (AVP). Rats were chronically instrumented for measurement of arterial blood pressure and vascular conductances in the renal, mesenteric and hindquarters beds.
Anandamide dose-dependently decreased the mean arterial blood pressure of rats made hypertensive by AII-AVP infusion, but not normotensive rats. Interestingly, acute hypertension also revealed a hypotensive response to WIN55212-2, which caused hypertension in normotensive animals. The enhanced depressor effects of the cannabinoids in acute hypertension were associated with increased vasodilatation in hindquarters, renal and mesenteric vascular beds. Treatment with URB597, which inhibits anandamide degradation by fatty acid amide hydrolase, potentiated the depressor and mesenteric vasodilator responses to anandamide. Furthermore, haemodynamic responses to WIN55212-2, but not to anandamide, were attenuated by the CB1 receptor antagonist, AM251.
The sphingomyelin cycle plays and important role in the regulation of cell physiology in the central nervous system. Ceramide generated by challenge of astroglial cells to cannabinoids may serve as a second messenger in the control of several functions [e.g., metabolic regulation and induction of apoptosis. The notion that the CB1 cannabinoid receptor, like the 55- kDa TNF receptor, may control the activity of the sphingomyelin cycle and of mitogen-and stress-activated protein kinases points to a general role of cannabinoids as modulators of glial cell fate. By showing that the CB1 cannabinoid receptor may be coupled to FAN independently of Gi/o proteins, this report opens a new conceptual view on the mechanism of cannabinoid action and contributes to the novel idea that G protein-coupled receptors may signal via ceramide as well as by mechanisms alternative to the classical heterotrimeric-G protein paradigm.
The DCLHK sequence is conserved in rat, human, mouse and cat CB1 receptors, located in the C-terminal portion of the CB1 receptor in a domain of the protein potentially involved in the interaction with cytoplasmic effectors.
The cannabinoid 1 (CB1) receptor antagonist SR141716A reversed the actions of URB-597 and OMDM-2, but not PMSF, without affecting reward thresholds by itself.
Results indicate that ACEA (2.5 mg/kg, i.p.) co-administered with PMSF (30 mg/kg, i.p.), significantly enhanced the anticonvulsant activity of phenobarbital.
THC induced a transient breakdown of sphingomyelin in cells expressing dominant-negative factor associated with neutral sphingomyelinase activation.
As expected, THC-induced sphingomyelin breakdown occurred in concert with an elevation of intracellular ceramide levels.
THC increases mRNA encoding the immediate early genes zif-268, c-fos and c-jun and FosB protein in the cingulate area of the rat prefrontal cortex.
THC-induced working memory deficits in a delayed alternation T-maze task are associated with altered dopamine and noradrenaline turnover in the rat prefrontal cortex.
Rats must shift attentional bias (or ‘set’) between different abstract features of stimuli, a process termed ‘attentional set shifting’. In contrast, in order to perform reversal-learning discriminations, rats must update contingencies between stimuli and reward presentation when these are reversed. Acute administration of D9-THC impairs performance on reversal learning stages of the task, whilst attentional set shifting ability is unaffected.
Initial evidence that antagonism of CB1 receptors may improve certain memory processes was obtained using an olfactory recognition task. As mature rodents normally spend more time investigating unfamiliar than familiar conspecific animals, the olfactory recognition task measures social short-term working memory capacity. In this task, administration of SR141716A alone improves olfactory recognition memory in both aged rats and mice. In addition, SR141716A improves working memory performance on the 8-arm radial maze when long delay periods are included. These studies have therefore, suggested that SR141716A may exert nootropic effects when administered alone, and, by extension, indicate that the endocannabinoid system may negatively influence some mnemonic processes.
Analysis of these results has led to the suggestion that the effects of SR141716A administration on working memory are dependent on temporal components of the task, and that CB1 blockade may prolong the duration of memory rather than facilitating learning.
SR141716A did not block URB597-mediated attenuation of KainicAcid-evoked burst firing.
CB1 receptors are involved in the control of excitatory glutamatergic neurotransmission. Blockade
of AEA metabolism could therefore confer inhibitory effects via suppression of excitatory synapses under hyperexcitable conditions.
AEA has been shown to directly modulate a number of seven-transmembrane and nuclear receptors, including GPR55 and peroxisome proliferator-activated receptors (reviewed in Alexander and Kendall, 2007), and voltage and ligand-gated ion channels, in some cases at intracellular sites, including T-type calcium channels, voltage-gated, and background potassium channels, a7-nicotinic acetylcholine receptors, TRPV1 receptors, and 5-HT3 serotonin receptors.
This work found that administration of a CB1 antagonist during febrile seizures blocked seizure induced potentiation of DSI, eliminated seizure-induced CB1 receptor upregulation, and prevented the development of long-term limbic hyperexcitability.
Furthermore, this study indicates that by inhibiting the degradation of AEA and other endocannabinoids, specific FAAH inhibitors such as URB597 may provide us with new hope for effectively lowering IOP by enhancing aqueous humor outflow.
But the FAAH inhibitors also produced large elevations in the levels of two anandamide analogs, palmitoylethanolamide and oleoylethanolamide, whose biological effects are independent of CB1 receptors.
We have developed a new class of agents that prevents anandamide
inactivation by targeting the intracellular enzymatic activity
of FAAH. URB597, the most potent member of this class,
inhibited FAAH activity with an IC50 value of 4 nM in brain membranes
and 0.5 nM in intact neurons, and an ID50 value of 0.15
mg kg–1 after systemic administration in the rat. This compound
had much greater selectivity for FAAH than other cannabinoid related
targets, including cannabinoid receptors (selectivity
index, >25,000) and MGL, an enzyme involved in the deactivation
of the endogenous cannabinoid ester 2-AG (selectivity
index, >7,500). Such target discrimination was matched by a lack
of overt cannabimimetic effects in vivo. Thus, at doses that almost
abolished FAAH activity and substantially raised brain anandamide
levels, URB597 and its analog URB532 did not evoke
catalepsy, reduce body temperature or stimulate feeding, three
key symptoms of cannabinoid intoxication in the rodent11.
Nevertheless, the compounds did elicit marked anxiolytic-like
responses, which paralleled their ability to inactivate FAAH and
were prevented by the CB1 receptor antagonist rimonabant. We
interpret these findings to indicate that URB597 and URB532 may
selectively modulate anxiety-like behaviors by enhancing the
tonic actions of anandamide on a subset of CB1 receptors which
may normally be engaged in controlling emotions. Forebrain sites
that might be implicated in such actions include the basolateral
amygdala, the anterior cingulate cortex and the prefrontal cortex,
all key elements of an “emotion circuit”33 that contains high densities
of CB1 receptors21,22. CB1 receptors in these structures are localized
to the axon terminals of a subpopulation of GABAergic
interneurons, which also express the peptide cholecystokinin23,34
(CCK). The anxiogenic properties of CCK35 and the ability of CB1
agonists to inhibit K+-evoked CCK release from hippocampal
slices36 indicate that interactions between this peptide and anandamide
may participate in the control of anxiety.
In addition to their anxiolytic-like actions, URB597 and
URB532 exerted modest anti-nociception in a model of acute
pain, which also was sensitive to CB1 receptor blockade. These
findings are similar to those reported for Faah–/– mice9 and support
the proposed roles of anandamide in the intrinsic modulation
of pain37. However, as emotional states may strongly
influence pain sensation, it is possible that anxiolysis might
have contributed to the mild anti-nociceptive effects of the
FAAH inhibitors.
URB597 and URB532 increased brain anandamide levels without
modifying those of the second endogenous cannabinoid,
2-AG. It is therefore likely that the pharmacological actions of
these compounds, which are sensitive to the CB1 antagonist rimonabant,
are primarily due to anandamide accumulation. But
the FAAH inhibitors also produced large elevations in the levels
of two anandamide analogs, palmitoylethanolamide and
oleoylethanolamide, whose biological effects are independent of
CB1 receptors7,8. Thus, we cannot exclude the possibility that additional
properties of URB597 and URB532, mediated by these
fatty ethanolamides, remain to be discovered.
We have recently reported
that THC induces sphingomyelin breakdown and intracellular
ceramide accumulation in primary astrocytes in a timeand
dose-dependent manner (Sa´nchez et al., 1998b; Bla´zquez
et al., 1999). Because rat primary astrocytes express the CB1
receptor mRNA (Bouaboula et al., 1995a) and protein
(Sa´nchez et al., 1998a), experiments were conducted to test
whether THC-evoked sphingomyelin breakdown was dependent
on this receptor. As shown in Fig. 1, the effect of 1 mM
THC was prevented by 1 mM SR141716, a selective CB1
receptor antagonist, but not by 1 mM SR144528, a selective
CB2 receptor antagonist. The synthetic cannabinoid agonist
HU-210 at 50 nM also stimulated sphingomyelin hydrolysis.
The endogenous cannabinoid ligand anandamide induced
sphingomyelin breakdown at 50 but not at 25 mM. Because
primary astrocytes have a high capacity to take up and
degrade anandamide (Di Marzo et al., 1994), we tested the
effect of PMSF, an inhibitor of anandamide hydrolysis, on
anandamide action. When coincubated with 100 mM PMSF,
25 mM anandamide was able to evoke maximal sphingomyelin
breakdown (Fig. 1). Likewise, methanandamide, a stable
synthetic analog of anandamide, induced maximal sphingomyelin
hydrolysis at 25 mM, indicating that anandamide
action is blunted by cellular degradation. The synthetic CB2
selective agonist JWH-133 at 50 nM did not significantly
affect sphingomyelin levels (Fig. 1). Interestingly, although it
is well established that cannabinoid receptors are coupled to
Gi/o proteins, 50 ng/ml pertussis toxin was unable to prevent
THC-induced sphingomyelin breakdown (Fig. 1), whereas
under identical experimental conditions, pertussis toxin fully
blocked THC-induced activation of extracellular signal-regulated
kinase (Bouaboula et al., 1995b) and protein kinase B
(Go´mez del Pulgar et al., 2000) (results not shown).
To test whether THC-induced sphingomyelin hydrolysis
also occurs in other cells expressing the CB1 receptor, primary
neurons, U373 MG astrocytoma cells, and CHO cells
transfected with the CB1 receptor cDNA were examined.
However, THC was unable to induce a significant breakdown
of sphingomyelin in these cells (Fig. 2).
The Adaptor Protein FAN Couples the CB1 Cannabinoid
Receptor of Astrocytes to Sphingomyelin Breakdown.
Extensive studies on the 55-kDa TNF receptor have
finely defined the domains of the receptor that allow coupling
to sphingomyelinase activation (Adam-Klages et al., 1998;
Kolesnick and Kro¨nke, 1998). A protein designated as FAN
(for factor associated with neutral sphingomyelinase activation)
has been shown by Kro¨nke and coworkers (Adam-
Klages et al., 1996; Kreder et al., 1999) to couple the NSD (for
neutral sphingomyelinase activation domain) of the 55-kDa
TNF receptor to neutral sphingomyelinase activation. FAN
contains five WD repeats in its C-terminal portion that serve
as functional motifs to facilitate defined protein-protein interactions.
Interestingly, b subunits of heterotrimeric G proteins
are also WD-repeat proteins (Adam-Klages et al., 1998).
We therefore examined whether the CB1 receptor may be
coupled to FAN in primary astrocytes and in U373 MG astrocytoma
cells, the latter selected as an example of cells in
which THC is unable to induce sphingomyelin hydrolysis.
For this purpose, the CB1 receptor was precipitated with a
specific antibody and FAN was subsequently detected by
immunoblotting. As shown in Fig. 3, FAN from primary
astrocytes was precipitated by the anti-CB1 receptor antibody.
Furthermore, pretreatment of astrocytes with THC
favored the binding of FAN to the CB1 receptor, whereas
SR141716 prevented this association. By contrast, the effect
of THC was not evident in U373 MG astrocytoma cells, despite
the presence of FAN in these cells.
To test whether the FAN-CB1 receptor interaction is functionally
relevant, we used ECV304 cells stably transfected
with either full-length FAN or a truncated, dominant-negative
form of FAN that does not bind to the NSD domain of the
55-kDa TNF receptor and therefore blocks TNF-induced
sphingomyelin breakdown and ceramide generation (Adam-
Klages et al., 1996; Se´gui et al., 1999). In line with a previous
report (Liu et al., 2000), ECV304 cells were shown to express
the CB1 receptor (Fig. 4A). As shown in Fig. 4B, THC induced
CB1 Cannabinoid Receptor and Sphingomyelin Hydrolysis 957
a transient breakdown of sphingomyelin in cells expressing
wild-type FAN but not in cells expressing dominant-negative
FAN. The involvement of the CB1 receptor in THC-induced
sphingomyelin hydrolysis was proved by the antagonistic
effect of SR141716. As expected, THC-induced sphingomyelin breakdown occurred in concert with an elevation of intracellular ceramide levels (Fig. 4C). HU-210 also induced
sphingomyelin hydrolysis in ECV304 cells expressing wildtype
FAN, and this effect was prevented by SR141716 (results
not shown).
The notion that FAN is coupled to the CB1 receptor is
strengthened by the homology between the NSD of the 55-
kDa TNF receptor and a region of the CB1 cannabinoid
receptor. NSD is a short, nine-amino-acid motif that includes
the sequence DSAHK (Adam-Klages et al., 1996), and the
CB1 receptor contains the highly homologous sequence
DCLHK at amino acid positions 431 to 435 (Matsuda et al.,
1990). The DCLHK sequence 1) is conserved in rat, human, mouse and cat CB1 receptors is located in the C-terminal portion of the CB1 receptor (i.e., in a domain of the protein potentially involved in the interaction with cytoplasmic effectors); and 3) is not
present in the CB2 receptor, which, in HL-60 cells at least, is
not coupled to sphingomyelin hydrolysis (results not shown).
It is difficult to evaluate whether the aforementioned sequence
homology between the NSD of the 55-kDa TNF receptor
and the NSD-like portion of the CB1 receptor is actually
significant. In this respect, it is worth noting that CD40,
a member of the TNF receptor superfamily, has been recently
shown to evoke sphingomyelin hydrolysis via FAN (Se´gui et
al., 1999). The sequence QETLH in the cytoplasmic domain of
CD40, the one that fits better with a portion of the NSD of the
55-kDa TNF receptor (EDSAH), shares a lower similarity
with the latter than the CB1 receptor. Nevertheless, as we
are aware, because the CB1 receptor is not coupled to FAN in
U373 MG astrocytoma cells, which express FAN, additional,
still-unknown factors may be necessary for the CB1 receptor
to activate sphingomyelin hydrolysis.
The sphingomyelin cycle plays and important role in the
regulation of cell physiology in the central nervous system
(Kolesnick and Kro¨nke, 1998). Ceramide generated by challenge
of astroglial cells to cannabinoids may serve as a second
messenger in the control of several functions [e.g., metabolic
regulation (Sa´nchez et al., 1998b; Bla´zquez et al.,
1999) and induction of apoptosis (Galve-Roperh et al., 2000)].
The notion that the CB1 cannabinoid receptor, like the 55-
kDa TNF receptor, may control the activity of the sphingomyelin
cycle (the present report) and of mitogen- (Bouaboula
et al., 1995b) and stress-activated protein kinases (Rueda et
al., 2000) points to a general role of cannabinoids as modulators
of glial cell fate. By showing that the CB1 cannabinoid
receptor may be coupled to FAN independently of Gi/o proteins,
this report opens a new conceptual view on the mechanism
of cannabinoid action and contributes to the novel idea
that G protein-coupled receptors may signal via ceramide
(Limatola et al., 1999) as well as by mechanisms alternative
to the classical heterotrimeric-G protein paradigm (Hall et
al., 1999).
The physical description of a completely free electron differs substantially
from the description of a bound electron. Because the mass of the electron is so
small, it reflects a behavior that is near the boundary between being described
as a particle and being described as a wave. Traveling far from any nucleus, the
electron behaves more like a particle. When it enters the region of a charged
nucleus that has an unoccupied electron state, the wave nature predominates
in response to the vibrating field of the nucleus, and the electron settles into
a stable standing wave pattern. If the nucleus were not vibrating, there would
be nothing to stop the electron from penetrating as a particle to the center
and interacting directly with the nucleus. Thus, these random vibrations of
the nucleons caused by the neutrinos and their tendency to behave like targets
that are very unfeasible for electrons to impact are what allow for stable atomic
structures.
The above description of the neutrino as the coordinator and sustainer of
atomic behavior encourages an alternate and more fundamental explanation of
black hole behavior. We believe that the absence of a fully developed omnidirectional
neutrino distribution will prevent some stable electron states from
persisting in super dense stars. As soon as the total path-integrated collision
cross section along any essentially radial path in such a star is large enough to
shield the central core from a large fraction of the incident neutrinos (and their
interaction with nucleons as described above), that core coulombically collapses
to higher density [15
Current information indicates that our universe is expanding at the rate of 50−100km/sec/megaparsec
With any external neutrino source, the ultimate fate of our universe has the same expansion or collapse possibilities as are provided in a Newtonian theory. However, a neutrino-induced gravity theory with outside neutrino sources, as contrasted with a Newtonian theory, would favor an expansion because the formation of black holes shields significant quantities of mass from neutrinos and thus prevents that mass, once “hidden”, from having any gravitational influence on other mass bodies.
The estimated average mass density of the universe is 10^-29 grams/cm^3, and this can be alternately
expressed as an average relativistic energy density of 3 x 10^-9 erg/cm^3.
The average neutrino energy density required to account for induced gravity is 10^27 erg/cm^3, and most of this neutrino energy continuously escapes from the universe at speeds in excess of other known material and without interacting with any mass particles.
Approximating the diameter of a nucleon as 10^-13cm, then an atomic nucleus
with atomic weight of 35 has a diameter of 3 x 10^-13cm. Average neutrino
spacing is 1.5 x 10^-11cm and they are moving at speed c and traveling in
random directions. A 2.5MeV neutrino has a mass of 1/400 AMU. Electrons
have a mass of 1/1862 AMU, and the inner electron states have a diameter
of 10^-8cm. This large void between the nucleus and the average radius of the
inner most electron states can be explained by the inability to establish a stable
electron standing wave pattern at distances closer to the nucleus because of the
large (and multipole) electromagnetic fluctuations (some being destabilizing to
a standing wave) in the near field region of a charged nucleus that is subjected
to such small and random displacements hundreds or thousands of times each
second.
The inner-most electron states behave as standing waves (closed complete
surfaces with non-zero thickness) whose fundamental frequency is determined
by the dipolar electromagnetic disturbances produced in the nucleons by the
shorter collision events. These are the most tightly bound electrons and are
more sensitive (than are more removed electrons) to this high frequency electromagnetic
mode. An electron further from that nucleus behaving as a looselycoupled
standing wave (also a closed surface) establishes the pattern whose
fundamental frequency is matched to one of the lower frequency (associated
with longer collision events) dipolar electromagnetic disturbances. This more
remote electron standing wave pattern is more loosely coupled (lower coupling
constant) to the motion of the nucleons, and the lower frequency electromagnetic
disturbances do not exert much of an influence on the above-mentioned
inner electron states. Since the higher frequency disturbances for the outer electron
are too high and too weak to completely upset the fundamental frequency
behavior of that electron, these higher frequencies act mainly to superimpose
higher multipole perturbations on that standing wave. These electromagnetic
disturbances do not of themselves determine the energies of the electron states
that respond to them; they merely are able to transfer energy when necessary to
either establish or maintain those states. The average positions of these standing
waves relative to the nucleus establish their principle quantum numbers, and
the perturbations to the standing waves provide energy differentiation between
the states belonging to the same principle quantum number. Thus, quantization
of the electron states results from the quantizing of the electron standing wave
patterns (by integral wavelength relationships characteristic of standing waves)
caused indirectly by neutrino bombardment, and the nucleon electromagnetic
frequencies sustain certain of those candidate electron standing wave patterns
but do not of themselves impose quantization. Other quantization effects that
are similarly facilitated by neutrino bombardment are discussed [13, 14].
Because the electromagnetic disturbances that drive the electron states are
classical and derive from mechanical motion, the statistical relationships between
expectation values of conjugate variables that appear in the Heisenberg
Uncertainty Principle apply as well to these electron states, and their numerical
products are expected to remain considerably higher than the value of h/(2_)
(resulting normally in lack of spontaneous photon emission). As applied to these
electron states, the uncertainty relationship is used to describe the fundamental
delocalization of the electron mass (and associated charge) that is characteristic
of a standing wave (probability amplitude) description even in the absence of
external stimuli such as interrogating radiation.
The physical description of a completely free electron differs substantially
from the description of a bound electron. Because the mass of the electron is so
small, it reflects a behavior that is near the boundary between being described
as a particle and being described as a wave. Traveling far from any nucleus, the
electron behaves more like a particle. When it enters the region of a charged
nucleus that has an unoccupied electron state, the wave nature predominates
in response to the vibrating field of the nucleus, and the electron settles into
a stable standing wave pattern. If the nucleus were not vibrating, there would
be nothing to stop the electron from penetrating as a particle to the center
and interacting directly with the nucleus. Thus, these random vibrations of
the nucleons caused by the neutrinos and their tendency to behave like targets
that are very unfeasible for electrons to impact are what allow for stable atomic
structures.
The above description of the neutrino as the coordinator and sustainer of
atomic behavior encourages an alternate and more fundamental explanation of
black hole behavior. We believe that the absence of a fully developed omnidirectional
neutrino distribution will prevent some stable electron states from
persisting in super dense stars. As soon as the total path-integrated collision
cross section along any essentially radial path in such a star is large enough to
shield the central core from a large fraction of the incident neutrinos (and their
interaction with nucleons as described above), that core coulombically collapses
to higher density [15]. This onset condition is specified by
Atoms in the outer region similarly coulombically collapse, and the region of
collapse continues to rapidly spread outward, releasing large amounts of energy.
In the black hole extreme, there are no sustainable electron states, and the
only radiation emission that can emanate from such a black hole comes from
impinging external atoms just before they encounter the surface or from purely
nuclear phenomena especially transient ones.
Induced Gravity Model Based on External Impinging Neutrinos : Calculation of G in Terms of Collision Phenomena and Inferences to Inertial Mass and Atomic Quantization
Herein, we present a particle-based mechanism and mathematical formulation of gravity, focusing on the neutrino as the gravity-inducing particle. The mechanism is based on the primacy of momentum conservation and postulates an omni-directional distribution throughout the universe of fast small particles of finite mass that have a low probability of colliding with nucleons. The measured acceleration between two neighboring mass bodies results from an alteration of this distribution caused by nucleons of each body interacting with some of those particles. Based on findings establishing that the neutrino has mass, we evaluate the various neutrinos as external particle candidates. We show that for mass quantities up to several times that of the sun the form of the time rate of momentum transfer to each body is proportional to the product of the two body masses because of the probability nature of any collision process, and inversely proportional to the square of the distance between them because of the mathematical properties of an altered particle flux. A derived expression involving the neutrino momentum flux, the neutrino-nucleon collision cross section, and the nucleon mass replaces the constant G from the classical gravitational model. The neutrino momentum flux that is required to account for gravity is so large as to cause us herein to re-evaluate conventional notions in kinematics and the cause of inertial properties and to examine neutrino-nucleon collisions as a possible source of electromagnetic standing waves essential to establish electron shell states. This reasoning indicates that in a much more massive body that is accreting mass, a coulombic collapse to a black hole will ensue when external neutrinos lose the ability to penetrate in sufficient numbers to the central region.
Our work, and our interpretation of the Shnoll work
[1, 2, 3], and many other works by Shnoll, correlates very
well with the positron annihilation work of Vikin [19] showing
that the production of positronium from Na-22 undergoes
a maximum near the time of the New Moon, and a minimum
near the time of the Full Moon. At the time of the New Moon,
the Earth laboratory (whether measurements are of gravitational
interactions or of radioactive decay phenomena) faces
in the general direction of the line of the Moon and the Sun
for a short period of the day, and then rotates such that the laboratory
faces free and open space and distant stars during the
duration of the day, so that a large complement of neutrinos
falls uninterrupted onto the measuring device; also neutrinos
that are emitted by the Sun may be scattered by the Moon to
aff ect the data. During the Full Moon, however, the Earth laboratory
is always between the Moon and the Sun, and hence
the overall collision physics is considerably different.
Shnoll sums the interpretation of the work that he describes
within [1] by stating “Taken together, all these facts
can mean that we deal with narrowly directed wave fluxes”,
which he refers to as beams that are more narrow than the
aperture of the collimators of the apparatus (0.9 mm). Our
model and theory of gravity [11] is based on a flux of particles,
and the “narrow beam” is interpreted due to very lowangle
elastic scattering of external particles by the nucleons of
the celestial bodies [11, 12], particularly the Moon (near body
in [12]) and Sun (far body), such that some particles never
reach the detecting apparatus such as pendula, gravimeter, or
radioactive source-detector system.
Fundamental to Shnoll’s work is his assertion that these
periodic characteristic histograms relate to a wide variety of
phenomena ranging from bio-chemical phenomena, to the
noise in a gravitational antenna, to alpha decay. This is in
agreement with my own work and that of others, and I have
found that anomalies in gravity, radioactive decay of Po-210
(and Co-60), and changes in plant growth, orientation, and
physiology, as well as embryonic centriole-centriole separation
phenomena, and even DNA and its sheathing H2O, are
affected by the Earth-Moon-Sun relationship [10, 11, 12, 14,
19, 20, 17]. It has been shown by Gershteyn et al. [21] that
the value of G varies at least 0.054% with the orientation of
the torsion pendula masses with the stars, and that G is periodic
over the sidereal year [21]—this periodicity arguing for
a strong link between the Shnoll radioactive decay data and
gravity. Furthermore the Shnoll work [1] cites the possibility
of a space-time anisotropy in a preferential direction, and
refers to the drift of the solar system toward the constellation
Hercules. Our theoretical work in collision-induced gravity
shows that G is a function of collision cross-section of the
neutrino-nucleon interaction [11], and experimental work indicates
that G is a function also of at least temperature, phase,
and shape [22, 10]. Our very recent experimental work determined
that G=6.692_10��11 cubic meters per kg sec2 [15]
which compares very favorably with the slightly earlier work
of Fixler et al [22] using precision a interferrometric method
in conjunction with cold Cs atoms and a known Pb mass,
yielding G=6.693_10��11 cubic meters per kg sec2 — these
values being considerably larger than the normally utilized
value of 6.67_10��11. These data are in accord with an increasing
trend in G that could possibly be related to other
trends such as that cited by Shnoll [1].
Shnoll reports [1] that the subject histograms have a fine
structure that shows what he refers to as “macroscopic fluctuations”.
We have reported gravitational fluctuations [10]
that appear at random, and are associated with time intervals
of _0.13 sec, indicating another correlation between gravity
data and radioactive decay data. The gravitational fluctuations
that we detected were observed in the form of two Newton
cradle pendula dwelling near each other for prolonged periods
of time, but occurring in an unpredictable manner. We
tentatively correlated these events with signals arriving from
supernovae events that had occurred somewhere in the vastness
of the universe. We also had detected on 27 August 2001
a peak in the radioactive decay of our Po-210 source, far in
excess of two-sigma Poisson statistics, and later correlated
with the arrival of radiation from supernovae explosion SN
2001 dz in UGC 47, emitting energy in all neutrinos of the
order of 1046 joules.
All of the above points to the ubiquity of a model of nature
based on elementary impinging momentum-transferring
external particles that can be interrupted by mass particles,
rather than nature being based on the conventional four axiomatic
forces and their respective field theory. Furthermore,
in an external particle based model for gravity, there is no
need to invoke a purely mathematical “fabric” to space-time
curvilinearity according to geodesics or warping, nor is it necessary
to invoke Riemanian space, nor Minkowski space, but
instead space-time is considered to be of a fractal geometry,
and the trajectory of mass particles and photons through space
is curved because of collisions with neutrinos (WIMPS).
Although the collision cross-section of the neutrino with the photon is extremely low, the flux density of the neutrino in our region of the universe is extremely high, and we postulate that
the bending of light is due to that interaction. It seems that astrophysics is now poised to affirm modifications to Einstein’s theory of General Relativity, and this is not unexpected in that many recent findings have indicated that gravity is quantized. Understanding the nature and details of
this quantization is one of the very major challenges and objectives in physics of this new century.
See also [27] for corroboration by private communication
of periodic behavior of radioactive decay data during New
Moon
Oxidation of catechols to semiquinones and quinones is a mechanism of tumor initiation, not only for endogenous estrogens, but also for synthetic estrogens such as DES and BPA, a human carcinogen, because quinone reacts with DNA [15]
Recently, alkylphenols such as p-octylphenol (p-OP), p-nonylphenol (p-NP), and bisphenol A (2,2-bis(4-hydroxyphenyl)propane, BPA) have been recognized as endocrine-disrupting chemicals to interfere with hormones of animals as well as phthalic esters and styrene.
Among alkylphenols, BPA is widely used as a material for polycarbonate resins and epoxy resins,
and it may contaminate food from the inner coating of the can and migrate from polycarbonate tableware and plastic packaging.
Chemical and biological degradation of BPA have been reported by several researchers. Horikoshi et al. reported that nonylphenol polyethoxylate was photodegraded in the presence of titanium dioxide. Nonylphenol ethoxylate was oxidized by ozone and hydrogen peroxide.
On the other hand, there are many reports for biologically degrading and polymerizing alkylphenols such as BPA using microorganisms and enzyme
Ronen and Abeliovich observed microbial degradation of BPA and tribromophenol by sediments. Lobos et al. reported that Gram-negative aerobic bacteria could degrade BPA and its analogues. Furusawa et al. also found microorganisms which could degrade p-NP.
cytochrome c oxidase subunit II, GRB2-associated binding protein 2, adaptor-related protein complex 2, and guanine nucleotide exchange factor p532
A Novel Rodent Model of Autism: Intraventricular Infusions of Propionic Acid Increase Locomotor Activity and Induce Neuroinflammation and Oxidative Stress in Discrete Regions of Adult Rat Brain http://www.autismcanada.org/pdfs/ajbb.pdf
Propionic acid is commonly used as a food preservative in wheat and dairy food products and may be involved in the recent postulated increase in the incidence of autistic spectrum disorder cases in North America (approximately 1 in 166). A number of effects have been shown following PPA treatment, including catecholamine and proenkephalin gene induction[46], cytoskeletal phosphorylation[47], histone modulation[48], second messenger metabolism[49], impaired mitochondrial respiratory transport chain function[50,51], modulation of gap junctions[52] and immune system activation[53]. There is also evidence of variable PPA metabolism in a number of metabolic disorders such as propionic and methylmalonic acidemia[54], disorders of biotin[55] and B12 metabolism[56], as well as following valproate[57] and ethanol exposure[58]. These disorders are associated with developmental delay, seizure and episodes of paroxysmal metabolic dysfunction resulting in increased oxidative stress and are to some degree reminiscent of autism[59,60]. We have hypothesized that PPA may be a candidate environmental factor putatively involved in the diverse behavioral, neuropathological and gastrointestinal aspects of ASD[61]. In our initial studies we found that repeated microinfusions of PPA into the lateral cerebral ventricles of adult rats produced behavioral, electrophysiological and neuropathological effects consistent with ASD[61]. PPA treated animals exhibited increased locomotor activity and repetitive behaviors such as dystonic limb movements, retropulsion and axial hyperextension. Simultaneous electrophysiological examination of cortical, hippocampal and striatal EEG evidenced electrographic changes reminiscent of human complex partial seizure and movement disorder. These effects were apparent within minutes of microinfusion. Furthermore, repeated exposures resulted in increased behavioral and electrographic effects suggestive of a kindling process. Collectively these findings indicated that PPA may have permanent effects on brain function. Neuropathological analysis of hippocampus and external capsule white matter tissue revealed PPA related increases in reactive astrocytes and activated microglia in the absence of gross neuronal loss and apoptotic effects. Additional analyses of whole brain homogenates produced evidence of increased oxidative stress and impaired glutathione metabolism in PPA treated animals. These findings are consistent with the neuropathological changes found in ASD autopsy brains[8] as well as biochemical studies in ASD patients[27,31]. The present study extended the examination of the effects of intraventricular PPA infusion on behavior, neuropathology and oxidative stress levels in the adult rodent ASD model. In particular, we characterized PPA induced increases in locomotor activity with additional automated measures of horizontal and vertical activity. We also examined the neuropathological responses following the twice-daily treatment schedule, utilizing additional indices of microglial activation and neurotoxicity. Lastly, we examined pro- and antioxidative stress pathways in brain regions which have been previously implicated in ASD pathophysiology.
Propionic acid is also used as an inert ingredient in pesticide formulations.
Propionic acid (PPA) is a dietary and gut bacterial short chain fatty acid which can produce brain and behavioral changes reminiscent of ASD following intraventricular infusion in rats. Impairments in GSH and catalase levels may render CNS cells more susceptible to oxidative stress from a variety of toxic insults.
The cannabinoid 1 (CB1) receptor antagonist SR141716A reversed the actions of URB-597 and OMDM-2, but not PMSF, without affecting reward thresholds by itself.
THC increases mRNA encoding the immediate early genes zif-268, c-fos and c-jun and FosB protein in the cingulate area of the rat prefrontal cortex.
THC-induced working memory deficits in a delayed alternation T-maze task are associated with altered dopamine and noradrenaline turnover in the rat prefrontal cortex.
Rats must shift attentional bias (or ‘set’) between different abstract features of stimuli, a process
termed ‘attentional set shifting’. In contrast, in order to perform reversal-learning discriminations, rats must update contingencies between stimuli and reward presentation when these are reversed. Acute administration of D9-THC impairs performance on reversal learning stages of the task, whilst attentional set shifting ability is unaffected.
Initial evidence that antagonism of CB1 receptors may improve certain memory processes was obtained using an olfactory recognition task. As mature rodents normally spend more time investigating unfamiliar than familiar conspecific animals, the olfactory recognition task measures social short-term working memory capacity. In this task, administration of SR141716A alone improves olfactory recognition memory in both aged rats and mice. In addition, SR141716A improves working memory performance on the 8-arm radial maze when long delay periods are included. These studies have therefore, suggested that SR141716A may exert nootropic effects when administered alone, and, by extension, indicate that the endocannabinoid system may negatively influence some mnemonic processes.
Analysis of these results has led to the suggestion that the effects of SR141716A administration on working memory are dependent on temporal components of the task, and that CB1 blockade may prolong the duration of memory rather than facilitating learning.
SR141716A did not block URB597-mediated attenuation of KA-evoked burst firing.
CB1 receptors are involved in the control of excitatory glutamatergic neurotransmission. Blockade
of AEA metabolism could therefore confer inhibitory effects via suppression of excitatory synapses under hyperexcitable conditions.
AEA has been shown to directly modulate a number of seven-transmembrane and nuclear receptors, including GPR55 and peroxisome proliferator-activated receptors (reviewed in Alexander and Kendall, 2007), and voltage and ligand-gated ion channels, in some cases at intracellular sites, including T-type calcium channels, voltage-gated, and background potassium channels, a7-nicotinic acetylcholine receptors, TRPV1 receptors, and 5-HT3 serotonin receptors.
This work found that administration of a CB1 antagonist during febrile seizures blocked seizure induced potentiation of DSI, eliminated seizure-induced CB1 receptor upregulation, and prevented the development of long-term limbic hyperexcitability.
Furthermore, this study indicates that by inhibiting the degradation of AEA and other endocannabinoids, specific FAAH inhibitors such as URB597 may provide us with new hope for effectively lowering IOP by enhancing aqueous humor outflow.
We have developed a new class of agents that prevents anandamide
inactivation by targeting the intracellular enzymatic activity
of FAAH. URB597, the most potent member of this class,
inhibited FAAH activity with an IC50 value of 4 nM in brain membranes
and 0.5 nM in intact neurons, and an ID50 value of 0.15
mg kg–1 after systemic administration in the rat. This compound
had much greater selectivity for FAAH than other cannabinoid related
targets, including cannabinoid receptors (selectivity
index, >25,000) and MGL, an enzyme involved in the deactivation
of the endogenous cannabinoid ester 2-AG (selectivity
index, >7,500). Such target discrimination was matched by a lack
of overt cannabimimetic effects in vivo. Thus, at doses that almost
abolished FAAH activity and substantially raised brain anandamide
levels, URB597 and its analog URB532 did not evoke
catalepsy, reduce body temperature or stimulate feeding, three
key symptoms of cannabinoid intoxication in the rodent11.
Nevertheless, the compounds did elicit marked anxiolytic-like
responses, which paralleled their ability to inactivate FAAH and
were prevented by the CB1 receptor antagonist rimonabant. We
interpret these findings to indicate that URB597 and URB532 may
selectively modulate anxiety-like behaviors by enhancing the
tonic actions of anandamide on a subset of CB1 receptors which
may normally be engaged in controlling emotions. Forebrain sites
that might be implicated in such actions include the basolateral
amygdala, the anterior cingulate cortex and the prefrontal cortex,
all key elements of an “emotion circuit”33 that contains high densities
of CB1 receptors21,22. CB1 receptors in these structures are localized
to the axon terminals of a subpopulation of GABAergic
interneurons, which also express the peptide cholecystokinin23,34
(CCK). The anxiogenic properties of CCK35 and the ability of CB1
agonists to inhibit K+-evoked CCK release from hippocampal
slices36 indicate that interactions between this peptide and anandamide
may participate in the control of anxiety.
In addition to their anxiolytic-like actions, URB597 and
URB532 exerted modest anti-nociception in a model of acute
pain, which also was sensitive to CB1 receptor blockade. These
findings are similar to those reported for Faah–/– mice9 and support
the proposed roles of anandamide in the intrinsic modulation
of pain37. However, as emotional states may strongly
influence pain sensation, it is possible that anxiolysis might
have contributed to the mild anti-nociceptive effects of the
FAAH inhibitors.
URB597 and URB532 increased brain anandamide levels without
modifying those of the second endogenous cannabinoid,
2-AG. It is therefore likely that the pharmacological actions of
these compounds, which are sensitive to the CB1 antagonist rimonabant,
are primarily due to anandamide accumulation. But
the FAAH inhibitors also produced large elevations in the levels
of two anandamide analogs, palmitoylethanolamide and
oleoylethanolamide, whose biological effects are independent of
CB1 receptors7,8. Thus, we cannot exclude the possibility that additional
properties of URB597 and URB532, mediated by these
fatty ethanolamides, remain to be discovered.
Other members of the acylethanolamide lipid family are also produced by neurons and act through
G-protein-coupled receptors: homo-linolenylethanolamide (HEA) and docosatetraenylethanolamide (DEA) act through CB1 receptors
80% of the population have IQs ranging between 80 and 120 with 10% lying below 80, and 10% falling above 120.
Key to understanding this relationship is
the unification between leptonic neutrinos and gluons.
This manifests at lower energy values of particle couplings
and is observed in decay patterns of the highquark
meson complexes, such as the top- and bottomquarks,
but these are resonant energies of the up-quark
and the down-quark.
The proton-neutron interconversion acts to cause a mixing of wave functions and the exchange of a mesonic mediator. This is known as Yukawa coupling, and it is the Yukawa meson that carries the antiquark which couples to an up-quark of the proton. These couplings necessarily relate to
the Heisenberg zero-point energy (ZPE) metric background.
The net result is that the strong gluonic coupling can be
assumed by the weak antineutrino coupling in terms of
a neutral weak-interaction current. The current arises
from the triquark complex of a nucleon, and thus can
re-circulate; therefore the original nucleon (such as the
neutron in the +n inelastic interaction) can be rematerialized.
The associated long decay times are ideal
for heat carry-off. The significant point to this is that the quark-antiquark coupling is transmuted into a temporary diquark selfstate following a simple exchange of the state-antistate couplings of the neutral pions.
It is found that small decreases in gravity that are caused by planet syzygy, full moon presence, and cosmogonic events of deep space can cause a sufficient change in gravitational interactions
to affect the nucleons of a single cell
or a small nanocluster of cells after initial mitosis such that small but significant changes in normal centriole separation can occur. These slight modifications can cause modifications in bond lengths and bond angles of sheathing water molecules, and changes of the helical DNA structure, and lead to a mutation with adverse consequences.
This study was performed to investigate the geotropism and geotaxy of a life science system in order to correlate with predictions of our own external particle model for gravity [8-10].
Calculations indicate that the change in centriole-centriole separation due to the decreased gravity of a full moon interval (during which decreased gravity effects would be maximized) is of the order of tens of angstroms.
This variation in length scale is shown to alter the probability of reaching the activation energy to form a covalent bond in an emerging DNA helix, and create the possibility of a change in bond angle, bond length, and the elements entering the bond.
We have recently found indication of cosmogonic phenomena possibly affecting weak force interactions, and recommend also that experimental work in this sub-area be continued as related to unstable nuclides in organic systems.
Because of the modified chemical potential the effect on phosphorus bridging atoms is significant
The probability then of a miscopy in replication during mitosis will be enhanced by at least 10 percent, and thus the probability of a disadvantageous mutation leading to a birth defect will likewise increase.
The catenoid is of particular interest here since it is the same shape that Wheeler (1962) uses in his theory to describe how wormholes act as transducers for higher dimensional energy to influx into our 4D space/time reality. As similar idea for the influx of energy from higher dimensions has also been
proposed (Shacklett, 1993) based on Twistor theory (Peat, 1988) which is based on a unique topology composed of a catenoid inside the hole of a toroid
We have shown this thermodynamically (and through catalysis) during liquid-liquid short-range-order transitions in many molten elemental states to include sulfur, selenium, tellurium, lead, bismuth, tin, and mercury. We reported in those studies that short range order structural configurations become stable or persistently metastable.
Nanomolecular Gravitational Interactions Causing Increased Probability of Birth Defects in Humans During Period from Conception to Early Fetus Formation
Induced change in centriole separation and consequent probability for disadvantageous mutation
G. C. Vezzoli
Department of Physics and Mathematics
Benjamin Franklin Institute of Technology
41 Berkeley Street, Boston, MA 02116;
Research affiliate, The Farlow Herbaria
Harvard University, Cambridge, MA 02139
ABSTRACT
It is found that small decreases in gravity that
are caused by planet syzygy, full moon presence,
and cosmogonic events of deep space can cause
a sufficient change in gravitational interactions
to affect the nucleons of a single cell or a small
nanocluster of cells after initial mitosis such that
small but significant changes in normal centriole
separation can occur. These slight modifications
can cause modifications in bond lengths and
bond angles of sheathing water molecules, and
changes of the helical DNA structure, and lead
to a mutation with adverse consequences.
Key words: centrioles, nanoclusters, mutation,
sheathing water, gravity, cosmogonic
1 Introduction
1.1 Cellular Systems
Recent work employing sea urgin eggs and
embryos has shown that the centriole-centrosome
complex is altered during cell division when
exposed to microgravity, however, control cells
cultured in a centrifuge at 1g in space, and those
cultured on ground appear normal [1]. It was
reported that the separation of centrioles were
observed most significantly in 4% of the cells
that were exposed to microgravity [1]. Sea
urchins were employed for this study because of
their constituting an animal model system which
is ideal for the study of molecular, cell, and
developmental biology [2,3]. Experiments have
also been recently conducted in microgravity
using ceratopteris [4] and indicated that only as a
single-celled spore did the organism appear to
respond to gravity. It was also shown therein
that gravity detection takes place only during a
very crucial time which allows the effect to
influence subsequent cell polarity, cell
differentiation, direction of nuclear migration,
and direction of rhizoid growth – this time period
being referred to as the “polarity-determination
window”. The response is observed to be that
the nucleus migrates down to the bottom of the
front face of the spore to position itself for an
asymmetric division. The two consequent
daughter cells are not of equal size, and the
larger becomes the prothallus (upward growing
aerial part) whereas the smaller becomes the
rhizoid; the nuclear migration positions the first
cell division such that the rhizoid grows
downward.
The ceratopteris work relates to the microcurrent
studies conducted by Levengood and
Gedye [5,6] on impatiens and soybean plants in
which gravitationally polartropic electrical
effects are measured by a charge density pulse
capacitive technique. Their work also shows
that a gravitropic relationship is affected
by the position of the Sun.
1.2 Botanical systems
The above effects, though of small magnitude,
can have profound consequences, and fall under
what is becoming to be known under the general
category of “subtle energy effects”. We have
measured [7] a very close correlation of
enhanced growth/height of the extremity of a
parabolic cactus shoot corresponding to the time
interval of 99% to 100% visibility of the full
moon of August 3rd-5th, 2001 ( a period of a
slight decrease in gravity), and we have
measured a slight decrease in height during the
new moon (increased gravity) a fortnight
subsequent (heights measured vertically
with respect to a ground plane) – the effects
being of the order of 1-2 %. This study was
performed to investigate the geotropism and
geotaxy of a life science system in order to
correlate with predictions of our own external
particle model for gravity [8-10].
We have corroborated subtle gravitational effects
in our study of the heavy vine, Aristolochia
macrophylla (known as Ducthman’s Pipe
because of the pipe-like structure of its calyx) by
mapping the position of the tip of a cordate leaf
correlated with the position of the Sun passing
directly over the plane of support-fence of the
vine [7,11]. This work showed a small decrease
in the effect of gravity during the tine interval of
10:00 AM to 2:00 PM (EST) in experiments on
cloudless days in August 2001, the effect
observed consistently to be about 2%..
1.3 Macroscopic biological systems
Modern research has shown that Human
chorionic gonadotropin (HCG), secreted by the
human embryo, begins to circulate in maternal
blood very early in pregnancy, and established
[12] that HCG is concentrated and excreted in
maternal urine. The HCG hormone is actually
secreted by the embryonic chorionic villi cells
almost from the moment of conception, and
should be initially susceptible to gravitational
effects. The very correlation of the average
typical menstrual cycle and gestation period in
humans with the lunar month(s), and the
development of the normal monthly corpus
luteum cyst on the ovary (alerted to function by a
signal from the pituitary gland), suggest from a
physics standpoint some complex gravitational
correlation. Additional recent research, aimed at
decreasing the probability of premature births,
has shown that as an expectant mother
approaches delivery, a series of electrical signals
take place in the womb that cause muscle
contraction [13]. This effect and much of the
above phenomena may be a result of subtle
changes in the overall thermodynamic
environment to which sheathing water molecule
clusters are exposed, and a compliant response of
the structure of the water molecule and cluster to
that physical and/or chemical
perturbation/alteration. This viewpoint is borne
out by recent measurements giving the change in
the bond length of the water molecule as a
function of very small changes in temperature
and pressure [14 ], as well as indications of
changes in the resistivity of water depending
upon angle of the charge flow path vertical
gravity vector [7,12,14].
2 Theory an experiment
We have shown [8] that for an external
momenta-transfer theory of gravity, what was
thought in Newtonian theory to be the universal
gravitational constant, G, is actually a function of
gravity-bearing particle flux density, and
postulated that the external particle which is
responsible for gravitational interactions may be
the electron neutrino. We have reported
experimental support for G being a function by
showing that gravitational interactions depend
upon the temperature, shape, phase, and level of
disorder of a mass [9.10]. Much of our work that
relates to life sciences has focused on the
gravitational properties of water [14a]. The
water that exists inside living cell cytoplasm
changes between phases of disordered liquid and
ordered gelatinous solid, the fluctuation between
the two phases determined by the polymerization
of the actin cytoskeleton [16]. Water in a
microtubule environment will respond to subtle
energy gravitational effects[5,6,14]. In that
water is within and around DNA/protein
molecules the gravitational effects then become
very important relative to diffusion and life
processes. In addition to direct hydrogen bonds
between protein and DNA there are water
bridges that exist in virtually all complexes.
Nano-clustering of water molecules can range
from five or so as sheathing molecules to 57
molecules of water bound to a DNA fragment of
19 base pairs length [16]. Subtle changes in
gravity will effectuate slight changes in pressure,
as well as in the overall pressure tensor, and
cause consequent changes in the bond angle of
water from its normally established value of 104-
degrees 27-minutes to an altered value which
will consequently alter hydrogen bonding with
proteins. This alteration will have a polarizationinduced
dipole-dipole effect on the polymeric
structure and electrical properties of the protein
and of nerve cells and synapse responses.
We have reported [9.10] that at length scales of
less than 0.1 mm, gravitational properties do not
behave according to inverse square relationship,
but appear to conform to an inverse fourth
relationship. This has been predicted by string
physicists [17] who had reported that at less than
0.1 mm proximity new and extraordinary
physical behavior may be observed. ( The value
of 0.1 mm corresponds to the length scale that
gives rise to Einstein’s cosmological constant).
Our experiments also indicated that gravity has
a statistical property unlike the expected
behavior of a time-independent field [9,10].
The apparatus which we utilized to measure very
small effects of gravity is described in ref 9. We
tested this apparatus by measuring a decrease in
gravity at the time of the May 2001 Sun-planet
syzygy of the line-up of the Sun, Earth, Jupiter,
and Saturn, predicted at 2203 (UT) on May
18,’01. A cusp-like decrease in gravity was
observed in our study on the morning of May
15th between the hours of 0100 and 0500, and a
square dip in gravity was detected at 2010 UT on
May 18th lasting 35 seconds. A major anomaly
was also detected in a charge-density-pulse array
[15,5,6] in early morning hours of May 15th.
3 Calculations and Simulations
On the above basis, simulations and calculations
indicate that the change in centriole-centriole
separation due to the decreased gravity of a full
moon interval (during which decreased gravity
effects would be maximized) is of the order of
tens of angstroms. This variation in length scale
is shown to alter the probability of reaching the
activation energy to form a covalent bond in an
emerging DNA helix, and create the possibility
of a change in bond angle, bond length, and the
elements entering the bond. Because of the
modified chemical potential the effect on
phosphorus bridging atoms is significant. The
probability then of a miscopy in replication
during mitosis will be enhanced by at least
10 per cent, and thus the probability of a
disadvantageous mutation leading to a birth
defect will likewise increase.
Through the use of the Benard cell, it is reported
[18] that nonequilibrium magnifies the effects of
gravitation. The cell has a very small thickness
of only a few millimeters and is utilized to show
that at non-equilibrium gravitation will modify
diffusion flow. Detailed calculations using the
reaction diffusion equation show that
gravitation-induced changes in diffusion are
clearly shown near the bifurcation point of an
unperturbed system. The authors conclude that
“very small gravitational fields can lead to
pattern selection.” This result [18] is entirely
in accord with the results of our simulations
on cellular nanoclusters.
The above is expected also to be particularly true
during a chemical or a biochemical reaction
during which bonding is breaking down and then
new chemical bonding is being reconstructed.
Under these transient conditions, the species is
most susceptible to external stimuli. We have
shown this thermodynamically (and through
catalysis) during liquid-liquid short-range-order
transitions in many molten elemental states to
include sulfur, selenium, tellurium, lead,
bismuth, tin, and mercury [19]. We reported in
those studies that short range order structural
configurations become stable or persistently
metastable. It is reasonable to expect that during
the reconstruction of the thermodynamically
favored species, such as in polymer formation,
there would exist a preferentially high
vulnerability to gravitation and magnetic
influences during this transient interval.
4 Inferences and Further Work
We have endeavored to sensitize particularly
medical field researchers, consultants, and
practitioners regarding the consideration of
gravitational (and electromagnetic) interactions
during transient periods of molecular bonding
emphasizing very early fetus development (as
well as during the biochemical processes of
healing and joining). Subtle gravitational and
magnetic changes can be caused by lunar,
planetary, and deep space supernovae effecfts.
Data relating birth defects to syzygy effects
have been compiled by Gedye from the work of
Jones over a period of 30 years (2). It is strongly
recommended from the simulations and
calculations described herein that more
experimental research be conducted on early
embryo formation during variation of overall
thermodynamic conditions. We have recently
found indication of cosmogonic phenomena
possibly affecting weak force interactions,
and recommend also that experimental work in
this sub-area be continued [21] as related to
unstable nuclides in organic systems.
Cannabis sativa has been known, used, and misused by mankind for centuries, and yet only over the last two decades has research stemming from the chemical constituents specific to this plant, the cannabinoids, started to provide fundamental insights into animal physiology and pathology, resulting in the development of new therapeutics. The discovery of the endocannabinoid system, and its targeting with two new pharmaceutical preparations now on the market in several countries, represent the most recent example of how studies on medicinal plants and on the mechanism of their
biological effects can reveal, through a chain of breakthroughs, new systems of endogenous signals and physiological phenomena that can become the source of novel strategies for unmet therapeutic challenges.
Introduction
The cannabinoid CB1 receptor antagonist, rimonabant, has been marketed since August 2006 in several EU countries under the commercial name of Acomplia as a pharmacological aid to exercise and calorie-intake reduction for the treatment of obesity and its metabolic complications, such as dyslipidemia and glucose intolerance [1]. About a year earlier, Sativex, a pharmaceutical preparation based on extracts of Cannabis sativa, and containing the psychotropic cannabinoid Δ9-tetrahydrocannabinol (THC) together with the nonpsychotropic cannabidiol (Figure 1) in an 1:1 ratio, was introduced in Canada for the treatment of neuropathic pain associated with multiple sclerosis [2]. These recent milestones of the exploitation of the plant with perhaps the oldest history of medicinal and recreational use by mankind are the result of four decades of intensive research. This process started with the identification and chemical synthesis of THC, the controlled study of its pharmacological properties, and the identification of its receptors in animal organisms and of their endogenous ligands, the endocannabinoids (Figure 1), and it continued with the progressive understanding of the physiological and pathological roles of this newly discovered signaling system and the appreciation of the potential therapeutic use not only of THC and endocannabinoids, but also of other plant cannabinoids. Despite this impressive sequence of achievements, whose aspects have been the subject of recent “historical” reviews [3], [4] and [5], there is much more to the original understanding of the THC mechanism of action than the discovery of the endocannabinoid system. The purpose of this article is not merely to highlight the past contribution of chemical biology to our current understanding of endocannabinoid regulation and function, but, more importantly, to discuss the several other discoveries that stemmed, and are still likely to originate in the future, from the finding of cannabinoid receptors and their endogenous ligands.
Figure 1. Chemical Structures of the Most-Studied Endocannabinoids, of a Cannabinoid Receptor Antagonist, and of Some Plant Cannabinoids
Chemical structures of (1) the two best-studied endocannabinoids, anandamide and 2-arachidonoyl glycerol [7], [8] and [9]; (2) the CB1 receptor antagonist/inverse agonist rimonabant, now on the market under the trade name Acomplia, as a pharmacological aid for the therapy of obesity and the metabolic syndrome [1]; (3) the two major plant cannabinoids, the psychotropic Δ9-THC and the nonpsychoactive cannabidiol, which are also the major constituents, in a 1:1 ratio, of Sativex, currently marketed in Canada against neuropathic pain in patients with multiple sclerosis [2].
From Plant Chemicals to Chemical Signals: Are Endocannabinoids Just Like Endorphins?
Thanks to the chemical synthesis of enantiomerically pure THC analogs (Figure 1), it became clear that the pharmacological actions of this compound were not merely due to its capability to alter membrane permeability in a nonspecific way, but rather to the interaction with specific binding sites. The same analogs, once chemically modified and radiolabelled, served as a tool for the identification of these “cannabinoid” receptors in the rat brain [6]. The finding of the first cannabinoid receptor, the CB1, out of a series of previously cloned orphan G protein-coupled receptors (GPCRs), soon to be followed by the homology cloning of the second type of cannabinoid receptors, the CB2, marked the beginning of the discovery of the endogenous cannabinoid signaling system and prompted the search for endogenous ligands, much in the same way as the identification of receptors for another plant natural product, morphine, had led to the identification of the endorphins two decades earlier. This search, however, might have lasted for several years had it not been guided by a chemical concept, i.e., that, by homology to the highly lipophilic THC, physiological cannabinoid receptor ligands were to be looked for among endogenous lipids rather than peptides like the endorphins. This idea was also supported by the observation that CB1 receptors exhibit relatively high homology with the GPCRs for another family of lipid signals, the lysophosphatidic acids. The identification of the fatty acid ethanolamide anandamide (N-arachidonoylethanolamide) [7] and of its glycerol ester analog, 2-arachidonoyl-glycerol (2-AG) [8] and [9], as endogenous agonists of CB1 and CB2 receptors (Figure 1), and the subsequent finding of their metabolic pathways and enzymes (see [10] for an updated review; see Figure S1 in the Supplemental Data available with this article online), provided the basis for the study of the physiological and pathological role of this endogenous signaling apparatus.
Beyond the similar history of their discoveries, the commonalities between opioid and cannabinoid receptors have been known even before the discovery of the latter, and they include similar inhibitory actions on nociception, gastrointestinal and cardiovascular function, anxiety and stress, and facilitatory actions on food intake and reward in laboratory animals (see [11], [12] and [13] for recent reviews; Table S1). The coupling, via inhibitory Gi/o proteins, of these two receptors to similar intracellular signaling pathways [14] underlies, to some extent, these similarities, whereas interactions between these pathways [13] probably explain why antagonists of each receptor type sometimes counteract the pharmacological effects induced by the stimulation of the other. However, one should not get the impression that the endocannabinoid system is a mere functional duplication of opioidergic signaling. The emerging scenario, in fact, distinguishes between the general strategies of endocannabinoid and endogenous opioid signaling based on the fact that, unlike endorphins, anandamide and 2-AG are lipophilic compounds produced from membrane phosphoglycerides via Ca2+-sensitive biosynthetic pathways triggered on demand, rather than being prestored in secretory vesicles. Hence, because of their chemical nature, endocannabinoids do not typically function like hormones, but they instead act as local (autocrine or paracrine) mediators. This is clearly the case with endocannabinoid action in the brain, where the elevation of intracellular Ca2+ caused by postsynaptic neuron depolarization or stimulation of postsynaptic neurotransmitter receptors coupled to Ca2+ mobilization from intracellular stores, or both, stimulates enzymes catalyzing the biosynthesis of anandamide and, particularly, 2-AG. These compounds are then released from the neuron to activate presynaptic CB1 receptors that, in most cases via inhibition of voltage-activated calcium channels, reduce the release of both excitatory (e.g., glutamate) and inhibitory (e.g., GABA) neurotransmitters, thereby producing various effects on neuronal synapses [15]. This “retrograde” mode for endocannabinoid action (Figure S1) has been implicated in several physiopathological functions of the brain, including the control of food intake, habit-forming and mnemonic processes, neuronal plasticity, and excitotoxicity. Since the biosynthetic precursors for endocannabinoids seem to be ubiquitous in membranes, it is the reciprocal pattern of expression of endocannabinoid biosynthesising enzymes and cannabinoid receptors that determines the specificity of endocannabinoid action, whereas the localization of the degrading enzymes sets its duration. Indeed, the sn-1-specific diacylglycerol lipase (DAGL)-α catalyzing 2-AG release from diacylglycerols [16] is expressed in postsynaptic dendritic “spines” that make synapses with axon terminals expressing CB1 receptors [17] and [18]. This allows a lipophilic molecule like 2-AG to reach its target in close proximity to its site of biosynthesis. Also, one of the enzymes responsible for 2-AG degradation, the monoacylglycerol lipase (MAGL), is located in presynaptic neurons, thus allowing for the immediate inactivation of the endocannabinoid signal [19]. Elegant experiments established the time and space frames for endocannabinoid retrograde action [20] and [21], which can distinguish between neighboring CB1-expressing glutamate- and GABA-releasing neurons as targets [22] and [23]. The type and time coincidence of Ca2+-mobilizing stimuli play a major role in determining the occurrence of retrograde signaling by endocannabinoids [24] and [25].
Experiments are being performed to extend this mode of action also to CB2 receptors or to nonneuronal cells, including lymphocytes, macrophages, and microglial cells (for the control of the immune and inflammatory responses) [26] and [27]; endothelial cells (for the control of vascular tone and angiogenesis) [28]; adipocytes and pancreatic β cells (for the control of adipokine and insulin secretion) [29] or other endocrine cells [30]; and to reproductive tissues [31] and [32]. For example, the tight control in time and space of endocannabinoid biosynthesis and degradation within the framework of the chemical communication between the fertilized egg and cells of the oviduct and uterus is crucial for the correct implantation of the embryo [33]. Thus, although, like the endorphins, they exert a homeostatic function, the endocannabinoids, ultimately due to their chemical nature and peculiar biosynthetic pathways (and to the fact that constitutive CB1 receptors are much more widely distributed than originally thought, whereas CB2 receptors appear to be upregulated under several pathological conditions), play a local and yet more general function, seemingly regarding all aspects of animal health and disease (Table S1).
Faces and Facets of Endocannabinoid Metabolic Pathways and Enzymes
The interplay between chemistry and biology played a major role in the identification of the enzymes catalyzing endocannabinoid synthesis and degradation. The fatty acid amide hydrolase (FAAH), which catalyzes the hydrolysis of anandamide (and of other bioactive fatty acid amides, see below) and 2-AG, was isolated after the synthesis of inhibitors [34], which were then used for affinity chromatography purification of the enzyme. This eventually led to the cloning of FAAH [35], now considered to be a promising target for the development of new anxiolytic and analgesic drugs [36], [37] and [38]. Also, the X-ray structure of FAAH was obtained thanks to the fact that a “modified version” of the purified enzyme yields good crystals only when covalently bound to an irreversible active-site inhibitor [39]. As to the cloning of the DAGL-α and -β catalyzing 2-AG formation from diacylglycerols, this was achieved by using a bioinformatic approach, i.e., starting from the gene encoding a DAGL from Penicillium, and then “fishing” for orthologs in the sequenced genomes of increasingly complex animal organisms, ending with the human genome [16].
FAAH is an unusual enzyme since, unlike most serine hydrolases which employ a Ser-His-Asp triad, its catalytic mechanism involves a Ser-Ser-Lys triad [40] (Figure 2). This is consistent with mutagenesis and enzymological studies indicating that Ser241 plays a critical role as both acid and base in the hydrolytic cycle, whereas Lys142 is the activator of Ser241 [41] and [42]. Mutagenesis studies also involve Ser217, a residue conserved in all enzymes with an amidase signature sequence, in the catalytic mechanism of FAAH. This residue may act as a “bridge” that, through a proton shift, facilitates both the nucleophile attack and the exit of the leaving group. The FAAH crystal structure revealed the existence of an acyl chain-binding (ACB) channel for entry of hydrophobic substrates and a cytoplasmatic access (AC) channel for hydrophilic compounds, i.e., water for substrate hydrolysis and hydrophilic breakdown products. This latter channel is also likely to accommodate the polar head of anandamide and other fatty acid amides [40] and [43] (Figure 2). Despite its atypical catalytic mechanism, FAAH is inhibited by most classical serine hydrolase inhibitors, including trifluoromethyl ketones, fluorophosphonates, carbamates, and α-ketoheterocycle compounds (Table S2). The inhibitory mechanism of these compounds is based on the presence in their structures of a strong electrophile that engages the Ser241 nucleophile in either a covalently reversible or irreversible manner. However, the systematic evaluation of the selectivity of these FAAH inhibitors against other Ser hydrolases is necessary to delineate their therapeutic potential. A chemical proteomic approach known as “activity-based protein profiling” (ABPP) has been used to assess the selectivity of several FAAH inhibitors [44]. ABPP methods, by using active site-directed chemical probes, allow for the screening of inhibitors against multiple enzymes in parallel, and consequently for the detection of possible off-target enzymes [45]. More recently, a multidimensional protein-identification technology (MudPIT) was employed to identify the major off-targets for several FAAH inhibitors [46]. Using this method, it was shown that the carbamate compounds known as URB-597 [36] and BMS-1 (but not SA-72 [47]), the carbamoyl tetrazole LY2077855, and the α-keto-heterocycle OL-135 [37] act on off-targets [44], [45] and [46] (Table S2). Also, the recently developed irreversible inhibitors of DAGLs [48] are ideal candidates to be investigated with proteomics-type strategies. These compounds, known as O-3841 and O-3640, are fluorophosphonate derivatives of oleic acid and are at least selective against other proteins of the endocannabinoid system.
Figure 2. Schematic Representation of the Binding Site of Fatty Acid Amide Hydrolase
Schematic representation of the active site of fatty acid amide hydrolase (FAAH), with “hydrophobic” and “polar head” pockets (“ACB” and “AC” channels, respectively) to accommodate anandamide and other fatty acid amides, as deduced from crystallographic studies [39] and structure-activity relationship studies carried out with several analogs of FAAH inhibitors [43]. Note how the “AC” channel can theoretically accommodate bulkier groups than ethanolamine. Arachidonoyl-trifluoromethylketone (TFMK) and its analogs [34] were used for the affinity chromatography purification of FAAH [35], whereas methyl-arachidonoyl-fluoro-phosphonate (MAFP) was used to obtain crystals from a slightly modified and purified form of FAAH [39]. Carbamate inhibitors like URB597 (see also Table S2) were suggested to enter the active site in a way opposite that of the fatty acid derivatives, with the ester rather than the amide bond being cleaved by the catalytic action of Ser241 [43].
In view of the “only when and where needed” character of their action, and of the increasing evidence that endocannabinoids participate in several pathological conditions [10], it can be foreseen that inhibitors of their biosynthesis or catabolism will be used for the pharmacological treatment of disorders ranging from neuropathic pain and psychiatric/neurological disorders to hypertension and obesity, possibly in a more selective way than with cannabinoid receptor agonists (see [49] for a comprehensive review). However, two peculiar aspects of endocannabinoid metabolic pathways should call for caution when it comes to their therapeutic exploitation (Figure 3): (1) the high degree of redundancy with which endocannabinoids are made and/or degraded—this means that, for example, inhibiting just one of the several pathways that have been suggested so far for anandamide biosynthesis from N-arachidonoyl-phosphatidylethanolamine [50], [51] and [52], or only one of the several enzymes (FAAH, MAGLs, COX-2) that have been suggested to catalyze 2-AG hydrolysis [10] and [53], might not be sufficient to manipulate anandamide or 2-AG tissue levels, respectively; and (2) the observation that endocannabinoids, as with other bioactive lipids, are part of a sequence of enzymatic reactions leading to a corresponding sequence of chemical signals with distinct molecular targets and biological outputs. 2-AG, for example, is at the same time the product of a family of fundamental intracellular signals, the diacylglycerols, and the precursor of prostaglandin glycerol esters (via COX-2), suggested to act at noncannabinoid receptors [54], or of arachidonic acid (via MAGL), the progenitor of a plethora of mediators and an intracellular mediator itself. Thus, the blockade of DAGLs might not only reduce endocannabinoid signaling, but also may enhance protein kinase C-mediated signals, whereas inhibition of MAGL might lead to the accumulation of prostaglandin glycerol esters. Although it is likely that cellular and subcellular compartmentalization intervenes to segregate these potentially concurring pathways, and perhaps also to ensure that only one pathway contributes to the formation or inactivation of anandamide and 2-AG acting at cannabinoid receptors in a certain cell or tissue (Figure 3), much work remains to validate the efficacy and selectivity in vivo of inhibitors of endocannabinoid metabolism.
Figure 3. Redundancy, Functional Plasticity, and Target Multiplicity of Endocannabinoid Metabolic Pathways
(A) The three pathways proposed for N-arachidonoylphosphatidyl-ethanolamine conversion into anandamide as an alternative to the one represented in Figure S1 [50], [51] and [52]. Although speculative, it is possible that the multiplicity of the biosynthetic pathways of anandamide reflects to some extent its capability to interact at a submicromolar concentration with several molecular targets [126], including, in addition to cannabinoid receptors, opposing actions on TRPV1 (activation) and TRPM8 (inhibition) [127] channels (see Figure 5).
(B) Biosynthesis and degradation of 2-arachidonoylglycerol seen as a sequence of different signals acting on different targets at different times. Apart from being converted, as discussed in the text, to arachidonic acid and to a COX-2 derivative with specific targets, 2-AG can be transformed into, and produced from, 2-arachidonoyl-lysophosphatidic acid, which activates LPA receptors with relatively high homology with CB1 receptors [128]. Abbreviations: Abh4, α/β-hydrolase 4; CB1, CB2, cannabinoid receptors of type 1 and 2, respectively; COX-2, cycloxygenase-2; FAAH, fatty acid amide hydrolase; GPCR, G protein-coupled receptor; LPA, lysophosphatidic acid; lyso-PLD, lyso-phospholipase D; MAGL, monoacylglycerol lipase; PKC, protein kinase C; sPLA2, secretory phospholipase A2, PLC, phospholipase C; PGE2, prostaglandin E2; PTPN22, protein tyrosine phosphatase N22; TRPM8, transient receptor potential melastatin type 8 channel; TRPV1, transient receptor potential vanilloid type 1 channel.
Recent data have suggested, however, that some widely used pharmaceuticals might owe some of their therapeutic actions to the interaction with endocannabinoid-biosynthesizing or -inactivating proteins. In particular, some nonsteroidal anti-inflammatory drugs (NSAIDs) (Figure 4) possess this property. Indomethacin exerts anti-inflammatory actions that are partly antagonized by a CB2 receptor antagonist [55], whereas ibuprofen enhances the analgesic actions of anandamide in a way sensitive to both CB1 and CB2 antagonists [56], and flurbiprofen inhibits the spinal release of proalgesic peptides in a way that is antagonized by a CB1 antagonist [57]. Rofecoxib, a COX-2 inhibitor, synergizes with anandamide while elevating the tissue levels of anandamide and other analgesic fatty acid ethanolamides [58]. Indeed, one possible way to explain these findings is by suggesting that these NSAIDs also inhibit FAAH, as already shown by Fowler and collaborators for ibuprofen in 1997 [59]. More recently, the same group extended this property to other acidic NSAIDs, and they showed that it becomes more important when the extracellular pH is lower than 7, as during inflammatory conditions [60]. Meanwhile, other indomethacin derivatives, such as indomethacin methyl ester and indomethacin morpholinylamides (Figure 4), were also found to directly activate CB1 and CB2 receptors, respectively [61] and [62]. More intriguingly, a recent study [63] showed that, in rats and mice, acetaminophen (paracetamol) is converted in vivo into p-aminophenol and then N-arachidonoyl-phenolamine (AM404) (Figure 4), a compound capable of inhibiting both FAAH and anandamide cellular reuptake and elevating anandamide tissue levels [64] and [65]. The second reaction is catalyzed by FAAH (an enzyme that, under certain conditions, can facilitate the condensation of fatty acids with amines), thus opening the possibility that it might also occur with other aromatic amines used in the clinic and lead to aromatic amides capable of interacting with other proteins of the endocannabinoid system. Importantly, the analgesia on a hot plate of acetaminophen is blocked by CB1 receptor antagonists, thus confirming that this widely used drug does also act through enhancement of the endocannabinoid system [66].
Figure 4. Chemical Structures of Widely Used Therapeutic Drugs that Have Been Reported to Interact with Proteins of the Endocannabnoid System
The cycloxygenase inhibitor indomethacin, and some of its derivatives, were suggested to directly bind to and activate CB1 and/or CB2 receptors [61] and [62]. Despite the lack of chemical similarity with anandamide, the NSAIDs, rofecoxib, ibuprofen, and flurbiprofen, and the general anesthetic propofol were suggested to act, in part, by inhibiting FAAH-catalyzed anandamide degradation [56], [57], [58], [59], [60] and [67]. The NSAID acetaminophen, instead, was shown to act, in part, through the conversion into AM404 and subsequent indirect activation of cannabinoid receptors [63] and [66]. The antiobesity drug orlistat (tetrahydrolipstatin) was shown to potently inhibit the biosynthesis of 2-arachidonoylglycerol [16] and [48].
NSAIDs are not the only therapeutic drugs capable of interacting with endocannabinoid enzymes. The general anesthetic propofol (Figure 4) also inhibits FAAH, and a part of its sedating properties is due to the subsequent elevation of the brain levels of anandamide, which, via CB1 receptors, can induce sleep [67]. More recently, the antiobesity drug tetrahydrolipstatin (orlistat) (Figure 4) was shown to inhibit DAGL-α and -β and, hence, to reduce 2-AG levels in intact cells, at concentrations lower than those necessary to inhibit other lipases [16] and [48]. Although this compound inhibits obesity mostly by acting at the level of lipid assimilation, it is tempting to speculate that part of its actions are due to inhibition of 2-AG-induced, and CB1-mediated, gastrointestinal actions [68]. In summary, from these data the intriguing possibility emerges that we might already be using in the clinic, without knowing it, substances that act in part by manipulating endocannabinoid levels.
Back to Plants: Are Endocannabinoids Like Chili Peppers?
The chemical structure of anandamide is not so different from that of capsaicin (Figure 5A), the pungent fatty acid amide component of another plant with a long history of medicinal and nutritional use, the hot chili pepper Capsicum annuum. In fact, capsaicin is even more chemically similar to the aforementioned AM404 (Figure 4), which inhibits anandamide degradation [64] and [65]. After the identification by Caterina and colleagues [69] of the transient receptor potential vanilloid-type 1 channel (TRPV1, originally known as vanilloid VR1 receptor) as the molecular target of capsaicin (Figures 5B and 5C), we and others, based on these chemical considerations, began to investigate the possibility that this receptor and proteins of the endocannabinoid system share common ligands [70]. Compounds were synthesized that bind to CB1 receptors, FAAH, or the putative anandamide membrane transporter (Figure S1), on the one hand, and to TRPV1, on the other hand [71] and [72]. More importantly, it was possible to demonstrate that anandamide activates TRPV1 receptors [73] and [74]. Later, other long-chain fatty acid ethanolamides, i.e., the naturally occurring homologs of anandamide (Figure 5A), and AM404 itself, were found to stimulate the activity of TRPV1 receptors [72], [75], [76], [77] and [78], and to share this property with other derivatives of arachidonic acid [79]. Molecular-modeling techniques were used to demonstrate that the preferential conformations of these compounds in solution overlap with those of capsaicin [78] and [79] (Figure 5D). However, none of these endogenous compounds appeared to be nearly as potent as capsaicin at inducing TRPV1-mediated biological responses. Although we now know that the “vanilloid” activity of these compounds is dramatically increased by several regulatory factors [80], this observation, together with the original belief that vanilloid TRPV1 receptors, by being mostly expressed in sensory afferents, are used as receptors only for external painful stimuli (high temperature, low pH, plant toxins), seemed to rule out the existence of true “endovanilloids.”
Figure 5. Vanilloid Receptors and Endovanilloids
(A) Chemical structures of N-acyldopamines and oleoylethanolamide, identified after the discovery of endocannabinoids and of the receptors for capsaicin and resiniferatoxin, the transient receptor potential vanilloid type 1 (TRPV1) channel.
(B) Three-dimensional representation of a TRPV1 monomer with the binding site for capsaicin according to Jordt and Julius [129]. According to this model, aromatic stacking of the vanillyl moiety of capsaicin (as well as anandamide) with Tyr511 in the intracellular T2-T3 linker region stabilizes the binding of the aliphatic chain with a transmembrane site created by the T3 and T4 domains. The observation that the T2-T3 linker domain plays a crucial role in ligand recognition in both TRPV1 receptor and the menthol and “cold”-receptor, TRPM8, led to the identification of anandamide and NADA as TRPM8 antagonists [127].
(C) Model proposed by Gavva and colleagues according to which capsaicin, anandamide, and N-arachidonoyldopamine (NADA) bind to Tyr511 through hydrophobic binding with their aliphatic chain, whereas residues Trp549 and Thr550 are involved in binding with the vanillyl or cathecolamine moieties of capsaicin and NADA, respectively [130].
(D) Overlap of capsaicin and oleoylethanolamide conformations in solution, according to the molecular model proposed by Movahed et al. [78].
Meanwhile, however, increasing and conclusive evidence was obtained for the presence of TRPV1 receptors in the brain [81], [82] and [83], where these proteins are unlikely to be reached by exogenous stimuli, thus strongly suggesting the existence of endovanilloid ligands [84]. Considerations on the structure-activity relationships of synthetic vanilloid TRPV1 agonists, which indicated the necessity of (1) a long, unsaturated alkyl chain, (2) a secondary amide group, and (3) 3-hydroxy-4-methoxy substituents on the aromatic moiety, in order to achieve optimal interaction with the receptors [85] and [86] (Figure 5C), together with the realization that these prerequisites could be met, to some extent, only by putative endogenous amides of dopamine with long, unsaturated fatty acids, led first to the synthesis [87] and then the isolation from the brain of N-arachidonoyl- and N-oleoyl-dopamine [88] and [89]. These compounds (Figure 5A; Table 1) are the most potent and efficacious endovanilloids identified to date and are most abundant in brain regions rich in dopamine, in agreement with their potential role as endogenous TRPV1 activators and with their possible biosynthetic origin from the N-acylation of dopamine. They are accompanied by saturated homologs that, although inactive per se on TRPV1, are capable of enhancing the activity of other endovanilloids [90]. Thus, once again, the meeting of chemical and biological minds led to the finding of endogenous counterparts of a plant natural product. The importance of the discovery of N-acyl-dopamines, however, went beyond that of finding potent endogenous ligands for TRPV1 receptors, since it supported the hypothesis that animal tissues might make, and use as chemical signals, any combination between fatty acids and biogenic amines.
The possible combinations of amino acids or biogenic amines and the most abundant fatty acids found in mammalian tissues yield new potential endogenous mediators: the N-acyl-ethanolamines, N-acyl-dopamines, N-acyl-amino acids, and N-acyl-taurines [97], [98], [99] and [100]. Fatty acid primary amides have also been identified [135] and [136]. The targets and metabolism of only a few of the several hundred possible compounds have been determined to date [103], [104], [105], [106] and [107] and are summarized here. R2 = C12:0, C14:0, C16:0, C18:0, C18:1, C18:2, C18:3, C20:0, C20:3, C20:4, C22:0, C22:4, C22:5, C22:6, C24:0, C24:1 alkyl chains; R3 = residues of amino acids or GABA. COMT, catecholamine-O-methyl-transferase; FAAH, fatty acid amide hydrolase; PPAR, peroxisome-proliferator-activated receptor; TRPV, transient receptor potential vanilloid-type.
Bioactive Fatty Acid Amides: When Animal Cells Play Combinatorial Chemistry
That cells could “combine” different fatty acids and biogenic amines to make several possible permutations of different fatty acid amides had been deduced already from the discovery in rodents of N-acyl-amino acids such as N-arachidonoyl-glycine (NAGly) and N-arachidonoyl-alanine (Table 1), which share with fatty acid ethanolamides like anandamide a potent analgesic and anti-inflammatory activity and the property of being recognized by FAAH as substrates [91], [92] and [93]. This finding raised the possibility that any long-chain fatty acid available in tissues could be amidated with any of the 20 amino acids and their naturally occurring derivatives. This would lead to the origination of hundreds of potential endogenous mediators with functions and molecular targets to be discovered. This possibility seems to be confirmed by the recent identification of N-arachidonoyl-serine, a brain constituent with vasodilatory and anti-inflammatory activity [94], and by increasing evidence for the presence in rodent tissues of 40 other postulated fatty acyl amides [95] and [96].
How is chemical-biological research going to cope with this “invasion” of new small-molecule mediators? How to discover and measure their levels in tissues, reveal their metabolic pathways, understand their physiological and pathological roles and, most importantly, identify their molecular targets? Clearly, the employment of the most modern “omic” approaches for gene, protein, and metabolite profiling will be required to find a function and a “parent receptor” to these orphan mediators, as well as to guide their discovery. Some progress in this direction has already been made. For example, based on the assumption that at least some of these compounds would be FAAH substrates, Cravatt and collaborators used an original global metabolite-profiling strategy, consisting of comparing, by the use of liquid chromatography-electrospray-mass spectrometric (LC-ESI-MS) techniques, the lipid components of tissues from wild-type and FAAH null mice, to identify new fatty amides. This led to the identification of N-acyl-taurines (Table 1) as new endogenous amides whose levels are controlled by this enzyme [97] and [98]. A similar approach, using FAAH null mice treated with anandamide, led to the identification of a potential alternative pathway for the inactivation of this compound and other acylethanolamides through the formation of the corresponding O-phosphorylcholine derivatives [99]. Other comparisons between lipid profiles, for example those of distinct brain areas from mice at different phases of their estrous cycle [100], can be used to understand the function of the analytes. Multidimensional (tandem) mass spectrometric techniques applied to other types of lipidomic-like approaches 101 M.R. Wenk, The emerging field of lipidomics, Nat. Rev. Drug Discov. 4 (2005), pp. 594–610. View Record in Scopus | Cited By in Scopus (204)[101] and [102] also seem to be very promising for the discovery of even trace quantities of fatty acid amides belonging to several families, or for the analysis of already discovered compounds [95] and [100]. Thanks to the use of “common fragment” methods, all of the naturally occurring members of the same family of fatty acid amides with different acyl chains but yielding common fragments after MS-MS (Table 1) can be analyzed in the same run (see Figure S2). Furthermore, the use of the optimal chromatographic conditions and of LC-ESI-MS-MS allows for the analysis of several fatty acid amide classes at the same time.
Progress is also being made in the identification of receptors for bioactive fatty acid amides. Some serendipitous but nevertheless important discoveries, i.e., that oleoylethanolamide binds to and activates peroxisome proliferator-activated receptor α [103], or that N-arachidonoyl-serine activates an as-yet-unidentified endothelial cannabinoid receptor [94], were prompted by the pharmacological actions observed for these compounds. N-acyl-taurines, like acylethanolamides and acyldopamines, activate TRPV1 receptors, but they also gate a related plasma membrane cation channel, the TRPV4 receptor [104]. Also, the finding of two GPCRs, GPR119 and GPR18, as high-affinity receptors for oleoylethanolamide and NAGly, respectively [105] and [106], was the result of targeted approaches. The implications of industrial patents claiming that GPR55 might be a high-affinity target for palmitoylethanolamide have also been recently discussed [107]. However, in view of the observation that bioactive fatty acid amides can be promiscuous in their targets, and that the latter, as with other lipid mediators, encompass all types of receptors (i.e., GPCRs, nuclear receptors, ion channels [Figure 3]), it can be foreseen that more systematic approaches, such as the use of biospecific interaction analysis (BIAcore), protein or mRNA arrays, and even of virtual screening methodologies, will have to be used in the future for the “deorphanization” of these novel compounds and, at the same time, of the 150 G protein-coupled and 24 nuclear “orphan” receptors still awaiting assignment of endogenous ligands. These techniques, together with the MS methods mentioned above, will have to be applied to also investigate if other amides of fatty acids, for example with serotonin, histamine, adrenaline, and noradrenaline, as well as with trace amines, occur in mammalian tissues. Some of these compounds (e.g., N-arachidonoyl-serotonin, Figure 6) have already been synthesized and exhibit interesting pharmacological properties (see below).
Figure 6. “Tinkering” with Nature's Building Blocks
Combining the vanillyl moiety typical of several plant natural products with arachidonic acid or ricinoleic acid, and the further modification of the chemical structures, yields compounds with mixed activity at cannabinoid and vanilloid TRPV1 receptors, i.e., arvanil, O-1861, and phenyl-acetyl-ricinoleoyl-cyclopropylamide [71], [108] and [109]. The synthetic N-arachidonoyl-serotonin mimics Nature's capability to make amides between long-chain fatty acids and biogenic amines, and turned out to be a selective inhibitor of fatty acid amide hydrolase (Table S2) and a potent antagonist at TRPV1 channels [38] and [110]. Iodination of the vanillyl moiety of a natural compound like resiniferatoxin (RTX), or of synthetic natural product derivatives, such as the acetylvanillyl ester of resiniferol orthophenylacetate (ROPA) and nor-dihydrocapsaicin, can produce opposing effects on the activity at TRPV1 channels [111], [112], [113] and [114]. The combination of a natural product like olivetol and a long-chain fatty acid yielded CB-25, a potent cannabinoid receptor ligand with “protean” agonist activity in vitro and in vivo [115], [116] and [117]. Isobutyl analogs of anandamide are more potent than the parent compound at cannabinoid receptors, and this is perhaps the reason why the Echinacea components dodeca-2E,4E,8Z,10Z-tetraenoic acid- and dodeca-2E,4E-dienoic acid-isobutylamide are the only plant natural products apart from cannabinoids that activate cannabinoid CB2 receptors quite potently [118], [119], [120] and [121].
Think Like a Tinker: Making Endocannabinoid-Based Drugs with Nature's Bits and Pieces
If nature can combine chemical moieties to make small, multitarget chemical signals via dedicated metabolic pathways, the synthetic chemist can also put together naturally occurring building blocks to make drugs that can interact with multiple receptor types, thus obtaining, in theory, more efficacious and therapeutically useful pharmacological tools. Given the overlap between the potential clinical applications (pain, inflammation, emesis, cancer, etc.) and binding recognition properties of proteins of the endocannabinoid system and TRPV1 channels, one strategy to develop hybrid therapeutic drugs was to put together fatty acids and the vanillyl moiety of capsaicin, each opportunely modified in order to maximize the interaction of the end product with each postulated target. N-arachidonoyl-vanyllamide (arvanil) and its analog, O-1861 (Figure 6), were synthesized with this idea in mind, and they proved to be capable of potently activating TRPV1 receptors while acting as agonists at CB1 receptors and inhibitors of the cellular reuptake of anandamide [71] and [108]. Both compounds turned out to be more potent and efficacious analgesics than pure cannabinoid or vanilloid receptor agonists with comparable affinities for their respective receptors. The derivatization of the hydroxy group of ricinoleic acid, followed by amidation with chemically modified ethylamine “heads,” yielded compounds with antagonist/inverse agonist activity at CB2 receptors and agonist activity at TRPV1 receptors and, hence, potential application against inflammation [109]. The aforementioned N-arachidonoyl-serotonin not only inhibits FAAH, thus elevating endocannabinoid levels and acting as an indirect cannabinoid receptor agonist [110], but it is also a potent TRPV1 antagonist in vitro and in vivo, thus exhibiting equivalent activity against neuropathic pain as other compounds that are more potent at FAAH [38].
However, tinkering with natural products can also lead to unexpected results. For example, 5′-iodination of resiniferatoxin on its vanillyl moiety (Figure 6) transforms the ultrapotent agonist activity at TRPV1 channels of this plant toxin into the capability to antagonize these receptors, whereas 6′-iodination only weakens its agonist activity [111]. By converse, 6′-, rather than 5′-, iodination of the much less hindered nordihydrocapsaicin (the saturated analog of capsaicin) and of other vanillamide TRPV1 ligands is required to transform their agonist activity into potent TRPV1 antagonists [112], without decreasing the capability of some of these compounds to directly inhibit NF-kB activity, thus yielding dual target anti-inflammatory and proapoptotic agents [113]. Even more intriguingly, 5′-iodination of the acetylvanillyl ester of resiniferol orthophenylacetate, a resiniferatoxin analog (Figure 6), yields a compound that, instead of behaving as an antagonist (as in the case of 5′-I-resiniferatoxin) or of losing activity (as in the case of 6′-I-resiniferatoxin), is 5-fold more potent as an agonist than the noniodinated analog [114]. On the “cannabinoid side,” attaching a C-11 alkylamide “head” to olivetol, a plant-derived compound, led to compounds that, despite their limited conformational freedom compared to endocannabinoids, bind with higher affinity to both CB1 and CB2 receptors [115]. In this case, the surprise came from the dramatically different behavior of one these compounds (CB-25, Figure 6) in vitro and in vivo, where it can act as a CB1 partial agonist and CB2 “silent” antagonist or as a CB1 antagonist, respectively [116], thus belonging to the ever growing family of receptor “protean agonists” (i.e., compounds that can exhibit agonist, antagonist, or inverse agonist activities depending on the constitutive “tone” of their receptors [117]).
If man can imitate nature by making hybrid drugs, Nature can also imitate the human body by making endocannabinoid-like natural products that potently bind to cannabinoid receptors. This is the case for the alkylisobutylamides from the roots of Echinacea angustifolia [118], [119] and [120]. These compounds, and in particular dodeca-2E,4E,8Z,10Z-tetraenoic acid- and dodeca-2E,4E-dienoic acid-isobutylamide (Figure 6), bind to CB2 receptors with higher affinity than endocannabinoids, although this property explains only part of their strong immunomodulatory and anti-inflammatory properties [121]. The crosstalk between man and Nature extends even further since C18:1 and C18:2 fatty acid ethanolamides and their corresponding phospholipid precursors are also found in higher plant seeds and leaves [122] and [123], in which a functional homolog of the mammalian FAAH has been cloned [124]. These anandamide congeners are inactive at cannabinoid receptors but play a role in the control of plant growth via unidentified molecular targets [124] and [125]. These chemical, but not necessarily functional, similarities between plant metabolites and mammalian mediators underscore the global importance of certain metabolic pathways in eukaryotes, and they emphasize how cells from phylogenetically distant species can exploit similar building blocks and anabolic/catabolic strategies to respond to different biological demands.
Take Home Messages and Open Questions
From the data reviewed in this article it is clear that biological and pharmacological studies carried out with a chemical mind can reveal new physiological and pathological mechanisms and, eventually, solve clinical problems. The exciting walk from the psychotropic constituent of Cannabis to the understanding of the mechanism of its biological actions led to the discovery of the endocannabinoid system, a signaling apparatus whose function goes well beyond what could have been imagined from pharmacological studies on THC. The route from the endocannabinoids to the Capsicum pungent principle then led to the finding of endovanilloids, endogenous mediators whose role is yet to be fully understood. The discovery of endocannabinoids and endovanilloids paved the way for the finding of several other lipid signals, and it prompted, on the one hand, new strategies for the chemical synthesis of compounds with multiple pharmacological and therapeutic targets, and, on the other hand, the search for chemically similar compounds back in plants. Many open questions to which the meeting of chemistry and biology can provide an answer still remain. Just to name a few, these questions involve the understanding of the mechanisms and exact physiological meaning of the target and metabolic pathway promiscuity of fatty acid ethanolamides; the identification of the elusive protein(s) facilitating endocannabinoid membrane transport; the receptor “deorphanization” of the several tens of bioactive fatty acid amides that have been discovered, and their testing on the several TRP channels that have been identified so far, many of which are, like TRPV1, activated by plant natural products; the determination of the exact function and molecular targets of fatty acid ethanolamides in plants; and the understanding of the mechanism of action in animals of other phytocannabinoids, like the therapeutically promising cannabidiol. Thus, the exciting promenade from plant natural products to animal physiology and back might soon become a true treasure hunt.
Cannabinoids Potentiate Emotional Learning Plasticity in Neurons of the Medial Prefrontal Cortex through Basolateral Amygdala Inputs.
Laviolette SR, Grace AA.
Departments of Neuroscience, Psychiatry, and Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
Abstract
Cannabinoids represent one of the most commonly used hallucinogenic drug classes. In addition, cannabis use is a primary risk factor for schizophrenia in susceptible individuals and can potently modulate the emotional salience of sensory stimuli. We report that systemic activation or blockade of cannabinoid CB1 receptors modulates emotional associative learning and memory formation in a subpopulation of neurons in the mammalian medial prefrontal cortex (mPFC) that receives functional input from the basolateral amygdala (BLA). Using in vivo single-unit recordings in rats, we found that a CB1 receptor agonist potentiated the response of medial prefrontal cortical neurons to olfactory cues paired previously with a footshock, whereas this associative responding was prevented by a CB1 receptor antagonist. In an olfactory fear-conditioning procedure, CB1 agonist microinfusions into the mPFC enabled behavioral responses to olfactory cues paired with normally subthreshold footshock, whereas the antagonist completely blocked emotional learning. These results are the first demonstration that cannabinoid signaling in the mPFC can modulate the magnitude of neuronal emotional learning plasticity and memory formation through functional inputs from the BLA.
Intra-dorsal periaqueductal gray administration of cannabidiol blocks panic-like response by activating 5-HT1A receptors.
Soares Vde P, Campos AC, Bortoli VC, Zangrossi H Jr, Guimarães FS, Zuardi AW.
Neuroscience and Behavioral Sciences, School of Medicine of Ribeirão Preto, Campus USP, Ribeirão Preto, SP, Brazil. vanpaso@cb.ufrn.br
Abstract
Activation of 5-HT1A receptors in the dorsal periaqueductal gray (dPAG) impairs escape behavior, suggesting a panicolytic-like effect. Cannabidiol (CBD), a major non-psychotomimetic compound present in Cannabis sativa, causes anxiolytic-like effects after intra-dPAG microinjections by activating 5-HT1A receptors. In the present work we tested the hypothesis that CBD could also impair escape responses evoked by two proposed animal models of panic: the elevated T-maze (ETM) and electric stimulation of dPAG. In experiment 1 male Wistar rats with a single cannula implanted in the dPAG received a microinjection of CBD or vehicle and, 10 min later, were submitted to the ETM and open field tests. In experiment 2 escape electrical threshold was measured in rats with chemitrodes implanted in the dPAG before and 10 min after CBD microinjection. In experiment 3 similar to experiment 2 except that the animals received a previous intra-dPAG administration of WAY-100635, a 5-HT1A receptor antagonist, before CBD treatment. In the ETM microinjection of CBD into the dPAG impaired inhibitory avoidance acquisition, an anxiolytic-like effect, and inhibited escape response, a panicolytic-like effect. The drug also increased escape electrical threshold, an effect that was prevented by WAY-100635. Together, the results suggest that CBD causes panicolytic effects in the dPAG by activating 5-HT1A receptors.
Cannabinoids promote embryonic and adult hippocampus neurogenesis and produce anxiolytic- and antidepressant-like effects.
Jiang W, Zhang Y, Xiao L, Van Cleemput J, Ji SP, Bai G, Zhang X.
Neuropsychiatry Research Unit, Department of Psychiatry, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Abstract
The hippocampal dentate gyrus in the adult mammalian brain contains neural stem/progenitor cells (NS/PCs) capable of generating new neurons, i.e., neurogenesis. Most drugs of abuse examined to date decrease adult hippocampal neurogenesis, but the effects of cannabis (marijuana or cannabinoids) on hippocampal neurogenesis remain unknown. This study aimed at investigating the potential regulatory capacity of the potent synthetic cannabinoid HU210 on hippocampal neurogenesis and its possible correlation with behavioral change. We show that both embryonic and adult rat hippocampal NS/PCs are immunoreactive for CB1 cannabinoid receptors, indicating that cannabinoids could act on CB1 receptors to regulate neurogenesis. This hypothesis is supported by further findings that HU210 promotes proliferation, but not differentiation, of cultured embryonic hippocampal NS/PCs likely via a sequential activation of CB1 receptors, G(i/o) proteins, and ERK signaling. Chronic, but not acute, HU210 treatment promoted neurogenesis in the hippocampal dentate gyrus of adult rats and exerted anxiolytic- and antidepressant-like effects. X-irradiation of the hippocampus blocked both the neurogenic and behavioral effects of chronic HU210 treatment, suggesting that chronic HU210 treatment produces anxiolytic- and antidepressant-like effects likely via promotion of hippocampal neurogenesis.
Effect of cannabinoids on platelet serotonin uptake.
Velenovská M, Fisar Z.
Department of Psychiatry, 1st Faculty of Medicine, Charles University, Prague, Czech Republic.
Abstract
Serotonin is involved in many of the same processes affected by cannabinoids; therefore, we investigated in vitro and in vivo effects of these drugs on the function of serotonin transporter. The effect of Delta(9)-tetrahydrocannabinol (Delta(9)-THC), endocannabinoid anandamide and synthetic cannabinoid receptor agonist WIN 55,212-2 on platelet serotonin uptake and membrane microviscosity was examined in 19 marijuana smokers and 20 controls. (1) Serotonin uptake was inhibited at higher doses of Delta(9)-THC (IC(50) = 139 micromol/l), anandamide (IC(50) = 201 micromol/l) or WIN 55,212-2 (IC(50) = 17.4 micromol/l); the inhibition was found non-competitive. Delta(9)-THC, anandamide and WIN 55,212-2 produced different effects on the membrane microviscosity. (2) Maximal velocity of platelet serotonin uptake was significantly increased in a group of chronic marijuana smokers suffering impairment of cognitive functions when compared with controls. Opposite effect of marijuana smoking on the serotonin uptake efficiency was observed in males beside females. In summary, this study provides evidence that (1) Activity of serotonin transporter is acutely affected by cannabinoids at relatively high drug concentrations; this effect is indirect and can be partially accounted for the changes in the membrane microviscosity. (2) Increase of maximal velocity of the serotonin uptake could be understood as adaptation change in the serotonergic system induced by chronic cannabis use. A hypothesis was supported that lowered serotonin uptake may reflect a gender-related differences in effects of psychoactive cannabinoids.
Inhibition of monoamine oxidase activity by cannabinoids.
Fisar Z.
Department of Psychiatry, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Ke Karlovu 11, 120 00, Prague 2, Czech Republic. zfisar@lf1.cuni.cz
Abstract
Brain monoamines are involved in many of the same processes affected by neuropsychiatric disorders and psychotropic drugs, including cannabinoids. This study investigated in vitro effects of cannabinoids on the activity of monoamine oxidase (MAO), the enzyme responsible for metabolism of monoamine neurotransmitters and affecting brain development and function. The effects of the phytocannabinoid Delta(9)-tetrahydrocannabinol (THC), the endocannabinoid anandamide (N-arachidonoylethanolamide [AEA]), and the synthetic cannabinoid receptor agonist WIN 55,212-2 (WIN) on the activity of MAO were measured in a crude mitochondrial fraction isolated from pig brain cortex. Monoamine oxidase activity was inhibited by the cannabinoids; however, higher half maximal inhibitory concentrations (IC(50)) of cannabinoids were required compared to the known MAO inhibitor iproniazid. The IC(50) was 24.7 micromol/l for THC, 751 micromol/l for AEA, and 17.9 micromol/l for WIN when serotonin was used as substrate (MAO-A), and 22.6 micromol/l for THC, 1,668 micromol/l for AEA, and 21.2 micromol/l for WIN when phenylethylamine was used as substrate (MAO-B). The inhibition of MAOs by THC was noncompetitive. N-Arachidonoylethanolamide was a competitive inhibitor of MAO-A and a noncompetitive inhibitor of MAO-B. WIN was a noncompetitive inhibitor of MAO-A and an uncompetitive inhibitor of MAO-B. Monoamine oxidase activity is affected by cannabinoids at relatively high drug concentrations, and this effect is inhibitory. Decrease of MAO activity may play a role in some effects of cannabinoids on serotonergic, noradrenergic, and dopaminergic neurotransmission.