Tag Archives: cannabinoid receptors

The stress-regulated protein p8 mediates cannabinoid-induced apoptosis of tumor cells.

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“One of the most exciting areas of current research in the cannabinoid field is the study of the potential application of these compounds as antitumoral drugs. Here, we describe the signaling pathway that mediates cannabinoid-induced apoptosis of tumor cells. By using a wide array of experimental approaches, we identify the stress-regulated protein p8 (also designated as candidate of metastasis 1) as an essential mediator of cannabinoid antitumoral action and show that p8 upregulation is dependent on de novo-synthesized ceramide. We also observe that p8 mediates its apoptotic effect via upregulation of the endoplasmic reticulum stress-related genes ATF-4, CHOP, and TRB3. Activation of this pathway may constitute a potential therapeutic strategy for inhibiting tumor growth.”

http://www.ncbi.nlm.nih.gov/pubmed/16616335

“Marijuana has been used in medicine for many centuries, and nowadays there is a renaissance in the study of the therapeutic effects of cannabinoids. One of the most active areas of research in the cannabinoid field is the study of the potential antitumoral application of these drugs. Our results unravel the mechanism of cannabinoid antitumoral action by demonstrating the proapoptotic role of the stress protein p8 via its downstream targets ATF-4, CHOP, and TRB3.

The identification of this pathway may contribute to the design of therapeutic strategies for inhibiting tumor growth. In particular, our findings can help to improve the efficiency and selectivity of potential antitumoral therapies with cannabinoids.

Our results also support that cannabinoid treatment does not activate this pathway in nontransformed cells, in line with the belief that cannabinoid proapoptotic action is selective for tumor versus nontumor cells, and that cannabinoids act in a synergic fashion with ER stress inducers as well as with other antitumoral agents.

The identification of the p8-regulated pathway described here may contribute to the design of therapeutic strategies for inhibiting tumor growth. In particular, our findings can help to improve the efficiency and selectivity of a potential cannabinoid-based antitumoral therapy.”

http://www.sciencedirect.com/science/article/pii/S1535610806000857

Medical Marijuana and Chronic Pain: a Review of Basic Science and Clinical Evidence.

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“Cannabinoid compounds include phytocannabinoids, endocannabinoids, and synthetics.

The two primary phytocannabinoids are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), with CB1 receptors in the brain and peripheral tissue and CB2 receptors in the immune and hematopoietic systems.

The route of delivery of cannabis is important as the bioavailability and metabolism are very different for smoking versus oral/sublingual routes.

Gold standard clinical trials are limited; however, some studies have thus far shown evidence to support the use of cannabinoids for some cancer, neuropathic, spasticity, acute pain, and chronic pain conditions.”

http://www.ncbi.nlm.nih.gov/pubmed/26325482

Fatty acids, endocannabinoids and inflammation.

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“From their phylogenetic and pharmacological classification it might be inferred that cannabinoid receptors and their endogenous ligands constitute a rather specialised and biologically distinct signalling system.

However, the opposite is true and accumulating data underline how much the endocannabinoid system is intertwined with other lipid and non-lipid signalling systems.

Endocannabinoids per se have many structural congeners, and these molecules exist in dynamic equilibria with different other lipid-derived mediators, including eicosanoids and prostamides.

With multiple crossroads and shared targets, this creates a versatile system involved in fine-tuning different physiological and metabolic processes, including inflammation.

A key feature of this ‘expanded’ endocannabinoid system, or ‘endocannabinoidome’, is its subtle orchestration based on interactions between a relatively small number of receptors and multiple ligands with different but partly overlapping activities.

Following an update on the role of the ‘endocannabinoidome’ in inflammatory processes, this review continues with possible targets for intervention at the level of receptors or enzymes involved in formation or breakdown of endocannabinoids and their congeners.

Although its pleiotropic character poses scientific challenges, the ‘expanded’ endocannabinoid system offers several opportunities for prevention and therapy of chronic diseases.

In this respect, successes are more likely to come from ‘multiple-target’ than from ‘single-target’ strategies.”

http://www.ncbi.nlm.nih.gov/pubmed/26325095

Endocannabinoid System Contributes to Liver Injury and Inflammation by Activation of Bone Marrow-Derived Monocytes/Macrophages in a CB1-Dependent Manner.

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“Hepatic injury undergoes significant increases in endocannabinoids and infiltrations of macrophages, yet the concrete mechanisms of changes in endocannabinoids and the functions of macrophage-expressed cannabinoid receptors (CBs) are unclear…

In the chimeric murine model, we found that blockade of CB1 by administration of a CB1 antagonist inhibited the recruitment of Bone marrow-derived monocytes/macrophages (BMM) into injured liver using immunofluorescence staining and FACS, but it did not have effects on migration of T cells and dendritic cells without CB1 expression. Furthermore, activation of CB1 enhanced cytokine expression of BMM. In vivo, inhibition of CB1 attenuated the inflammatory cytokine level through real-time RT-PCR and cytometric bead array, ameliorating hepatic inflammation and fibrosis.

In this study, we identify inactivation of BMM-expressed CB1 as a therapeutic strategy for reducing hepatic inflammation and fibrosis.”

http://www.ncbi.nlm.nih.gov/pubmed/26320250

Age-related changes in the endocannabinoid system in the mouse hippocampus.

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“Previous studies have demonstrated that the endocannabinoid system significantly influences the progression of brain ageing, and the hippocampus is one of the brain regions most vulnerable to ageing and neurodegeneration.

We have further examined age-related changes in the hippocampalendocannabinoid system by measuring the levels of anandamide (AEA) and 2-arachidonoylglycerol (2-AG) in young and old mice from two different mouse strains.

We found a decrease in 2-AG but not AEA levels in aged mice.

In order to identify the cause for 2-AG level changes, we investigated the levels of several enzymes that contribute to synthesis and degradation of 2-AG in the hippocampus.

We found a selective decrease in DAGLα mRNA and protein levels as well as an elevated MAGL activity during ageing.

We hypothesize that the observed decrease of 2-AG levels is probably caused by changes in DAGLα expression and MAGL activity.

This finding can contribute to the existing knowledge about the processes underlying selective vulnerability of the hippocampus to ageing and age-related neurodegeneration.”

http://www.ncbi.nlm.nih.gov/pubmed/26278494

Effect of anandamide on endometrial adenocarcinoma (Ishikawa) cell numbers: implications for endometrial cancer therapy.

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“We have previously shown that patients with endometrial carcinoma express elevated concentrations of the endocannabinoid, anandamide (AEA), in both their plasma and their endometrial tissue and that the endometrial carcinoma cell line, Ishikawa, contains the receptors to which AEA binds.

Several studies have reported that human and rodent cancer cell lines die in response to high AEA concentrations.

The incidence of endometrial carcinoma continues to escalate and, although surgical treatment has improved, morbidity and mortality rates have not. A move towards a novel non-surgical therapeutic option is thus required, and the endocannabinoid system provides a good candidate target.

We aimed to investigate the effects of AEA on the survival and proliferation of an endometrial carcinoma cell model.

Our results show that AEA induces a decrease in Ishikawa cell number probably through inhibition of cell proliferation rather than cell death.

These data suggest that the increased plasma and tissue AEA concentrations observed in patients with endometrial cancer is a counter mechanism against further cancer growth and points to the endocannabinoid system as a potentially new therapeutic target.”

http://www.ncbi.nlm.nih.gov/pubmed/26312842

https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(15)60335-X/fulltext

Cannabinoids and Schizophrenia: Risks and Therapeutic Potential.

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“The endocannabinoid system has been implicated in psychosis both related and unrelated to cannabis exposure, and studying this system holds potential to increase understanding of the pathophysiology of schizophrenia.

Anandamide signaling in the central nervous system may be particularly important.

Δ9-Tetrahydrocannabinol in cannabis can cause symptoms of schizophrenia when acutely administered, and cannabidiol (CBD), another compound in cannabis, can counter many of these effects.

CBD may have therapeutic potential for the treatment of psychosis following cannabis use, as well as schizophrenia, possibly with better tolerability than current antipsychotic treatments. CBD may also have anti-inflammatory and neuroprotective properties.

Establishing the role of CBD and other CBD-based compounds in treating psychotic disorders will require further human research.”

http://www.ncbi.nlm.nih.gov/pubmed/26311150

http://www.thctotalhealthcare.com/category/schizophrenia/

Pregnenolone can protect the brain from cannabis intoxication.

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“Pregnenolone is considered the inactive precursor of all steroid hormones, and its potential functional effects have been largely uninvestigated.

The administration of the main active principle of Cannabis sativa (marijuana), Δ(9)-tetrahydrocannabinol (THC), substantially increases the synthesis of pregnenolone in the brain via activation of the type-1 cannabinoid (CB1) receptor.

Pregnenolone then, acting as a signaling-specific inhibitor of the CB1 receptor, reduces several effects of THC.

This negative feedback mediated by pregnenolone reveals a previously unknown paracrine/autocrine loop protecting the brain from CB1 receptor overactivation that could open an unforeseen approach for the treatment of cannabis intoxication and addiction.

These data indicate that THC increases pregnenolone through activation of the CB1 receptor…

In conclusion, this new understanding of the role of pregnenolone has the potential to generate new therapies for cannabis dependence.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4057431/

Enhancing Brain Pregnenolone May Protect Cannabis Intoxication but Should Not Be Considered as an Anti-addiction Therapeutic: Hypothesizing Dopaminergic Blockade and Promoting Anti-Reward.

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“Pregnenolone considered the inactive precursor of all steroid hormones, has recently been shown to protect the brain from Cannabis intoxication.

The major active ingredient of Cannabis sativa (marijuana), Δ9-tetrahydrocannabinol (THC) enhances Pregnenolone synthesis in the brain via stimulation of the type-1 cannabinoid (CB1) receptor.

This steroid has been shown to inhibit the activity of the CB1 receptor thereby reducing many of the effects of THC.

While this mechanism seems correct, in our opinion, Vallee et al., incorrectly suggest that blocking CB1 receptors could open unforeseen approaches to the treatment of cannabis intoxication and addiction.

In this hypothesis, we caution the scientific community that, other CB1 receptor blockers, such as, Rimonabant (SR141718) have been pulled off the market in Europe. In addition, CB1 receptor blockers were rejected by the FDA due to mood changes including suicide ideation.

Blocking CB1 receptors would result in reduced neuronal release of Dopamine by disinhibition of GABA signaling.

Long-term blockade of cannabinoid receptors could occur with raising Pregnenolone brain levels…”

http://www.ncbi.nlm.nih.gov/pubmed/26306328

Pro-inflammatory obesity in aged cannabinoid-2 receptor deficient mice.

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“Cannabinoid-1 receptor signaling increases the rewarding effects of food intake and promotes the growth of adipocytes, whereas CB2 possibly opposes these pro-obesity effects by silencing the activated immune cells that are key drivers of the metabolic syndrome.

Pro- and anti-orexigenic cannabimimetic signaling may become unbalanced with age because of alterations of the immune and endocannabinoid system…

CB2 agonists may fortify CB2-mediated anti-obesity signaling without the risk of anti-CB1 mediated depression that caused the failure of rimonabant.”

http://www.ncbi.nlm.nih.gov/pubmed/26303348