ENDOCANNABINOID SYSTEM: A multi-facet therapeutic target.

Posted on April 19, 2016 by David

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“Cannabis sativa is also popularly known as marijuana. It is being cultivated and used by man for recreational and medicinal purposes from many centuries.

Study of cannabinoids was at bay for very long time and its therapeutic value could not be adequately harnessed due to its legal status as proscribed drug in most of the countries.

The research of drugs acting on endocannabinoid system has seen many ups and down in recent past. Presently, it is known that endocannabinoids has role in pathology of many disorders and they also serve “protective role” in many medical conditions.

Several diseases like emesis, pain, inflammation, multiple sclerosis, anorexia, epilepsy, glaucoma, schizophrenia, cardiovascular disorders, cancer, obesity, metabolic syndrome related diseases, Parkinson’s disease, Huntington’s disease, Alzheimer’s disease and Tourette’s syndrome could possibly be treated by drugs modulating endocannabinoid system.

Presently, cannabinoid receptor agonists like nabilone and dronabinol are used for reducing the chemotherapy induced vomiting. Sativex (cannabidiol and THC combination) is approved in the UK, Spain and New Zealand to treat spasticity due to multiple sclerosis. In US it is under investigation for cancer pain, another drug Epidiolex (cannabidiol) is also under investigation in US for childhood seizures. Rimonabant, CB1 receptor antagonist appeared as a promising anti-obesity drug during clinical trials but it also exhibited remarkable psychiatric side effect profile. Due to which the US Food and Drug Administration did not approve Rimonabant in US. It sale was also suspended across the EU in 2008.

Recent discontinuation of clinical trial related to FAAH inhibitor due to occurrence of serious adverse events in the participating subjects could be discouraging for the research fraternity. Despite of some mishaps in clinical trials related to drugs acting on endocannabinoid system, still lot of research is being carried out to explore and establish the therapeutic targets for both cannabinoid receptor agonists and antagonists.

One challenge is to develop drugs that target only cannabinoid receptors in a particular tissue and another is to invent drugs that acts selectively on cannabinoid receptors located outside the blood brain barrier. Besides this, development of the suitable dosage forms with maximum efficacy and minimum adverse effects is also warranted.

Another angle to be introspected for therapeutic abilities of this group of drugs is non-CB1 and non-CB2 receptor targets for cannabinoids.

In order to successfully exploit the therapeutic potential of endocannabinoid system, it is imperative to further characterize the endocannabinoid system in terms of identification of the exact cellular location of cannabinoid receptors and their role as “protective” and “disease inducing substance”, time-dependent changes in the expression of cannabinoid receptors.”

http://www.ncbi.nlm.nih.gov/pubmed/27086601

The role of carbon monoxide on the anti-nociceptive effects and expression of cannabinoid 2 receptors during painful diabetic neuropathy in mice.

Posted on March 30, 2016 by David

“The activation of cannabinoid 2 receptors (CB2R) attenuates chronic pain, but the role played by carbon monoxide synthesized by the inducible heme oxygenase 1 (HO-1) on the anti-nociceptive effects produced by a selective CB2R agonist, JWH-015, during painful diabetic neuropathy remains unknown.

The activation of HO-1 enhanced the anti-nociceptive effects of JWH-015 in diabetic mice, suggesting that coadministration of JWH-015 with CORM-2 or CoPP might be an interesting approach for the treatment of painful diabetic neuropathy in mice.”

http://www.ncbi.nlm.nih.gov/pubmed/27020787

Cannabinoids inhibit insulin receptor signaling in pancreatic β-cells.

Posted on March 12, 2016 by David

“Optimal glucose homeostasis requires exquisitely precise adaptation of the number of insulin-secreting β-cells in the islets of Langerhans. Insulin itself positively regulates β-cell proliferation in an autocrine manner through the insulin receptor (IR) signaling pathway.

It is now coming to light that cannabinoid 1 receptor (CB1R) agonism/antagonism influences insulin action in insulin-sensitive tissues. However, the cells on which the CB1Rs are expressed and their function in islets have not been firmly established. We undertook the current study to investigate if intraislet endogenous cannabinoids (ECs) regulate β-cell proliferation and if they influence insulin action.

These findings provide direct evidence for a functional interaction between CB1R and IR signaling involved in the regulation of β-cell proliferation and will serve as a basis for developing new therapeutic interventions to enhance β-cell function and proliferation in diabetes.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3064093/

Cannabinoids Regulate Bcl-2 and Cyclin D2 Expression in Pancreatic β Cells.

Posted on March 12, 2016 by David

“Recent reports have shown that cannabinoid 1 receptors (CB1Rs) are expressed in pancreatic β cells, where they induce cell death and cell cycle arrest by directly inhibiting insulin receptor activation. Here, we report that CB1Rs regulate the expression of the anti-apoptotic protein Bcl-2 and cell cycle regulator cyclin D2 in pancreatic β cells. Treatment of MIN6 and βTC6 cells with a synthetic CB1R agonist, WIN55,212-2, led to a decrease in the expression of Bcl-2 and cyclin D2, in turn inducing cell cycle arrest in G0/G1 phase and caspase-3-dependent apoptosis. Additionally, genetic deletion and pharmacological blockade of CB1Rs after injury in mice led to increased levels of Bcl-2 and cyclin D2 in pancreatic β cells. These findings provide evidence for the involvement of Bcl-2 and cyclin D2 mediated by CB1Rs in the regulation of β-cell survival and growth, and will serve as a basis for developing new therapeutic interventions to enhance β-cell function and growth in diabetes.”

http://www.ncbi.nlm.nih.gov/pubmed/26967640

The endocannabinoid system: novel pathway for cardiometabolic Risk-factor reduction.

Posted on February 20, 2016 by David

“Although rimonabant has been approved for use in several countries, the Food and Drug Administration has expressed concern about the potential for adverse neurologic and psychiatric effects, considering the widespread distribution of CB1 receptors in the brain. While more research is clearly needed, the clinical evidence shows that CB1-receptor blockade with rimonabant improves multiple cardiovascular and metabolic variables, including body weight and waist circumference, HDL-C, triglycerides, and glucose metabolism. Furthermore, these effects, which are probably mediated by both peripheral and central actions in the ECS, appear to be greater than the improvements that would be expected from weight loss alone. There are multiple ongoing and planned studies with rimonabant as well as several other CB-receptor blockers (e.g., taranabant, CP-945,598). While diet and exercise are the cornerstones of cardiometabolic risk-factor reduction, improved pharmacotherapies are urgently needed. The ECS has provided us with new insights and a promising new avenue for the management of obesity and its associated cardiometabolic risk factors.”

http://www.ncbi.nlm.nih.gov/pubmed/18047036

The endocannabinoid system: potential for reducing cardiometabolic risk.

Posted on February 20, 2016 by David

“The endocannabinoid system (ECS) affects multiple metabolic pathways in the brain and other organs. The transmembrane CB receptors were cloned in the early 1990s, followed shortly thereafter by the discovery of endogenous ligands, now known as endocannabinoids.

Three general types of cannabimimetic compounds have been described: herbal CBs, which occur uniquely in the cannabis plant (Cannabis sativa); endogenous CBs (or endocannabinoids), which are produced in the brain and peripheral tissues; and synthetic CBs, which are functionally similar compounds synthesized in the laboratory.

Obesity is associated with increased risk for insulin resistance, type 2 diabetes, nonalcoholic fatty liver disease, atherogenic dyslipidemia, and cardiovascular disease. Recent studies indicate that the body protects itself from weight loss by lowering energy expenditure. Both energy consumption and energy expenditure are regulated by hormones from a number of organs that act on the brain, as well as neural signals emanating from the brain itself.

Lifestyle modification is the initial intervention for obesity, with emphasis on reducing calorie intake and increasing physical activity; pharmacotherapy may be indicated for certain cardiovascular and metabolic risk factors.

This review focuses on the link between the biology of the cannabinoid receptor type 1 (CB₁ receptor) system and body-weight regulation, as well as clinical data from studies of the first CB₁ receptor antagonist…”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2905146/

Vaccenic acid suppresses intestinal inflammation by increasing the endocannabinoid anandamide and non-cannabinoid signaling molecules in a rat model of the metabolic syndrome.

Posted on February 20, 2016 by David

“Vaccenic acid (VA), the predominant ruminant-derived trans fat in the food chain, ameliorates hyperlipidemia yet mechanisms remain elusive. We investigated whether VA could influence tissue endocannabinoids (EC) by altering the availability of their biosynthetic precursor, arachidonic acid (AA) in membrane phospholipids (PL).

Interestingly, VA increased jejunal concentrations of anandamide and those of the non-cannabinoid signaling molecules, oleoylethanolamide and palmitoylethanolamide, relative to CD (P<0.05). This was consistent with a lower jejunal protein abundance (but not activity) of their degrading enzyme, fatty acid amide hydrolase and mRNA expression TNFα and IL-1β (P<0.05).

The ability of VA to reduce 2-AG in the liver and VAT provides a potential mechanistic explanation to alleviate ectopic lipid accumulation. The opposing regulation of EC and other non-cannabinoid lipid signaling molecules by VA suggests an activation of benefit via the EC system in the intestine.”

http://www.ncbi.nlm.nih.gov/pubmed/26891736

Cannabinoids and autoimmune diseases: A systematic review.

Posted on February 17, 2016 by David

“Cannabinoids have shown to have a variety effects on body systems. Through CB1 and CB2 receptors, amongst other, they exert an effect by modulating neurotransmitter and cytokine release.

Current research in the role of cannabinoids in the immune system shows that they possess immunosuppressive properties. They can inhibit proliferation of leucocytes, induce apoptosis of T cells and macrophages and reduce secretion of pro-inflammatory cytokines.

In mice models, they are effective in reducing inflammation in arthritis, multiple sclerosis, have a positive effect on neuropathic pain and in type 1 diabetes mellitus.

They are effective as treatment for fibromyalgia and have shown to have anti-fibrotic effect in scleroderma.

Studies in human models are scarce and not conclusive and more research is required in this field.

Cannabinoids can be therefore promising immunosuppressive and anti-fibrotic agents in the therapy of autoimmune disorders.”

http://www.ncbi.nlm.nih.gov/pubmed/26876387

http://www.thctotalhealthcare.com/category/autoimmune-disease/

Cannabinoid receptor type 1 mediates high-fat diet-induced insulin resistance by increasing forkhead box O1 activity in a mouse model of obesity.

Posted on February 8, 2016 by David

“Hepatic glucose production is promoted by forkhead box O1 (FoxO1) under conditions of insulin resistance.

The overactivity of cannabinoid receptor type 1 (CB1R) partly causes increased liver fat deposits and metabolic dysfunction in obese rodents by decreasing mitochondrial function.

The aim of the present study was to investigate the role of FoxO1 in CB1R-mediated insulin resistance through the dysregulation of mitochondrial function in the livers of mice with high-fat diet (HFD)-induced obesity.

Taken together, our findings suggest that the anti-insulin resistance effect of AM251, which leads to an improvement of mitochondrial function in hepatic steatosis, is mediated through FoxO1.”

http://www.ncbi.nlm.nih.gov/pubmed/26847930

CB1 receptor blockade counters age-induced insulin resistance and metabolic dysfunction.

Posted on January 14, 2016 by David

“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.”

http://www.ncbi.nlm.nih.gov/pubmed/26757949