Tag Archives: CB1
Chronic alcohol exposure disrupts CB1 regulation of GABAergic transmission in the rat basolateral amygdala.
“The basolateral nucleus of the amygdala (BLA) is critical to the pathophysiology of anxiety-driven alcohol drinking and relapse.
The endogenouscannabinoid/type 1 cannabinoid receptor (eCB/CB1 ) system curbs BLA-driven anxiety and stress responses via a retrograde negative feedback system that inhibits neurotransmitter release, and BLA CB1 activation reduces GABA release and drives anxiogenesis.
Additionally, decreased amygdala CB1 is observed in abstinent alcoholic patients and ethanol withdrawn rats.
Here, we investigated the potential disruption of eCB/CB1signaling on GABAergic transmission in BLA pyramidal neurons of rats exposed to 2-3 weeks intermittent ethanol.
In the naïve rat BLA, the CB1agonist WIN 55,212-2 (WIN) decreased GABA release, and this effect was prevented by the CB1 antagonist AM251. AM251 alone increased GABA release via a mechanism requiring postsynaptic calcium-dependent activity.
This retrograde tonic eCB/CB1 signaling was diminished in chronic ethanol exposed rats, suggesting a functional impairment of the eCB/CB1 system.
In contrast, acute ethanol increased GABAergic transmission similarly in naïve and chronic ethanol exposed rats, via both presynaptic and postsynaptic mechanisms.
Notably, CB1 activation impaired ethanol’s facilitation of GABAergic transmission across both groups, but the AM251-induced and ethanol-induced facilitation of GABA release was additive, suggesting independent presynaptic sites of action.
Collectively, the present findings highlight a critical CB1 influence on BLA GABAergic transmission that is dysregulated by chronic ethanol exposure and, thus, may contribute to the alcohol-dependent state.”
The endocannabinoid system and NGF are involved in the mechanism of action of resveratrol: a multi-target nutraceutical with therapeutic potential in neuropsychiatric disorders.
“Resveratrol is a polyphenolic compound with antioxidant, anti-inflammatory, and neuroprotective effects. It has also shown antidepressant-like effects in the behavioral studies; however, its mechanism(s) of action merit further evaluation.
Resveratrol like the classical antidepressant, amitriptyline, affects brain NGF and eCB signaling under the regulatory drive of CB1receptors.”
The G1359A-CNR1 gene polymorphism is associated to glioma in Spanish patients.
“The cannabinoid receptor gene 1 (CNR1) encodes the human cannabinoid receptor CB1.
This receptor has a widespread distribution in the central nervous system (CNS), the main ligands being anandamide, 2-araquidonoil glycerol and marijuana constituents.
There is evidence to suggest an anti-neoplastic effect of these ligands in glial tissues mediated through stimulation of the receptor.
Our results suggest that allele G of the CNR1 gene could be associated with a lower susceptibility to glioma.”
http://www.ncbi.nlm.nih.gov/pubmed/21156413
“A glioma is a primary brain tumor that originates from the supportive cells of the brain, called glial cells.” http://neurosurgery.ucla.edu/body.cfm?id=159
“Remarkably, cannabinoids kill glioma cells selectively and can protect non-transformed glial cells from death.” http://www.ncbi.nlm.nih.gov/pubmed/15275820
“Cannabinoids, the active components of Cannabis sativa…” http://www.ncbi.nlm.nih.gov/pubmed/17952650
CB1 receptor blockade counters age-induced insulin resistance and metabolic dysfunction.
“The endocannabinoid system can modulate energy homeostasis by regulating feeding behaviour as well as peripheral energy storage and utilization.
Importantly, many of its metabolic actions are mediated through the cannabinoid type 1 receptor (CB1R), whose hyperactivation is associated with obesity and impaired metabolic function.
Herein, we explored the effects of administering rimonabant, a selective CB1R inverse agonist, upon key metabolic parameters in young (4 month old) and aged (17 month old) adult male C57BL/6 mice…
Collectively, our findings indicate a key role for CB1R in aging-related insulin resistance and metabolic dysfunction and highlight CB1R blockade as a potential strategy for combating metabolic disorders associated with aging.”
Interactions between the endocannabinoid and nicotinic cholinergic systems: preclinical evidence and therapeutic perspectives.
“Many behavioral and neurochemical effects of nicotine that are related to its addictive potential are reduced by pharmacological blockade or genetic deletion of type-1 cannabinoid receptors, inhibition of endocannabinoid uptake or metabolic degradation, and activation of peroxisome proliferator-activated-receptor-α. On the other hand, cholinergic antagonists at α7 nicotinic acetylcholine receptors as well as endogenous negative allosteric modulators of these receptors are effective in blocking dependence-related effects of cannabinoids.
CONCLUSIONS:
Pharmacological manipulation of the endocannabinoid system and endocannabinoid-like neuromodulators shows promise in the treatment of nicotine dependence and in relapse prevention. Likewise, drugs acting at nicotinic acetylcholine receptors might prove useful in the therapy of cannabinoid dependence.”
Anti Proliferative and Pro Apoptotic Effects of Flavonoid Quercetin Are Mediated by CB1 Receptor in Human Colon Cancer Cell Lines.
“Quercetin, the major constituent of flavonoid and widely present in fruits and vegetables, is an attractive compound for cancer prevention due to its beneficial anti proliferative effects, showing a crucial role in the regulation of apoptosis and cell cycle signaling.
In vitro studies have demonstrated that quercetin specifically influences colon cancer cell proliferation.
Our experiments, using human colon adenocarcinoma cells, confirmed the anti proliferative effect of quercetin and gave intriguing new insight in to the knowledge of the mechanisms involved…
These findings open new perspectives for anticancer therapeutic strategies.”
http://www.ncbi.nlm.nih.gov/pubmed/25893829
“Flavonoid glycosides and cannabinoids from the pollen of Cannabis sativa L.” http://www.ncbi.nlm.nih.gov/pubmed/15688956
The Endocannabinoid Signaling System in the CNS: A Primer.
“The purpose of this chapter is to provide an introduction to the mechanisms for the regulation of endocannabinoid signaling through CB1 cannabinoid receptors in the central nervous system.
The processes involved in the synthesis and degradation of the two most well-studied endocannabinoids, 2-arachidonoylglycerol and N-arachidonylethanolamine are outlined along with information regarding the regulation of the proteins involved.
Signaling mechanisms and pharmacology of the CB1 cannabinoid receptor are outlined, as is the paradigm of endocannabinoid/CB1 receptor regulation of neurotransmitter release.
The reader is encouraged to appreciate the importance of the endocannabinoid/CB1 receptor signaling system in the regulation of synaptic activity in the brain.”
CB1 cannabinoid receptor enrichment in the ependymal region of the adult human spinal cord
“Cannabinoids are involved in the regulation of neural stem cell biology and their receptors are expressed in the neurogenic niches of adult rodents.
In the spinal cord of rats and mice, neural stem cells can be found in the ependymal region, surrounding the central canal, but there is evidence that this region is largely different in adult humans: lacks a patent canal and presents perivascular pseudorosettes, typically found in low grade ependymomas.
Using Laser Capture Microdissection, Taqman gene expression assays and immunohistochemistry, we have studied the expression of endocannabinoid system components (receptors and enzymes) at the human spinal cord ependymal region.
We observe that ependymal region is enriched in CB1 cannabinoid receptor, due to high CB1 expression in GFAP+ astrocytic domains. However, in human spinal cord levels that retain central canal patency we found ependymal cells with high CB1 expression, equivalent to the CB1HIGH cell subpopulation described in rodents.
Our results support the existence of ependymal CB1HIGH cells across species, and may encourage further studies on this subpopulation, although only in cases when central canal is patent. In the adult human ependyma, which usually shows central canal absence, CB1 may play a different role by modulating astrocyte functions.”
Computational Prediction and Biochemical Analyses of New Inverse Agonists for the CB1 Receptor.
“Human cannabinoid type 1 (CB1) G-protein coupled receptor is a potential therapeutic target for obesity.
The previously predicted and experimentally validated ensemble of ligand-free conformations of CB1 are used here to predict the binding sites for known CB1-selective inverse agonists including rimonabant and its seven known derivatives.
This binding pocket, which differs significantly from previously published models, is used to identify 16 novel compounds expected to be CB1 inverse agonists by exploiting potential new interactions.
We show experimentally that two of these compounds exhibit inverse agonist properties including inhibition of basal and agonist-induced G-protein coupling activity, as well as an enhanced level of CB1 cell surface localization.
This demonstrates the utility of using the predicted binding sites for an ensemble of CB1 receptor structures for designing new CB1 inverse agonists.”