Cannabinoids cool the intestine

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“Inflammatory bowel diseases (IBDs) such as ulcerative colitis and Crohn’s disease affects over a million people in the United States, with an estimated indirect cost from work loss of $3.6 billion annually. Many of these individuals suffer from pain, diarrhea and poor ability to digest their food, and in up to half of those with IBD, the disease is so severe that it ultimately requires surgery to remove the affected bowel segment.

Historically, marijuana has been used to treat diarrhea and has been advocated for the treatment of a variety of other gastrointestinal problems, including Crohn’s disease.

More recent pharmacological studies have clearly established that cannabinoids inhibit gastrointestinal motility and secretion by acting on CB1 receptors located on the terminals of both intrinsic and extrinsic submucosal neurons.

When administered to mice with chemically induced enteritis, cannabinoids also reduce inflammation and fluid accumulation in the gut.

Cannabinoids inhibit motility and secretion in the intestine.

They are now assigned the additional task of curbing excessive inflammation, suggesting that drugs targeting the endogenous cannabinoid system could be exploited for inflammatory bowel disease.

These findings may offer a new therapeutic approach to IBD.”

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2516444/

 

ENDOCANNABINOID SYSTEM: A multi-facet therapeutic target.

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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

Synthesis and pharmacological evaluation of new biphenylic derivatives as CB2 receptor ligands.

“Targeting type-2 cannabinoid receptor (CB2) is considered a feasible strategy to develop new drugs for the treatment of diseases like neuropathic pain, chronic inflammation, neurodegenerative disorders and cancer.

Such drugs are devoid of the undesired central side effects that are typically mediated by the CB1 receptor.

In this work we synthesized 18 biphenylic carboxamides as new CB2-selective ligands and evaluated their pharmacological profiles. The functional activity of these compounds is strongly influenced by the nature of the substituent at position 4′ and 5 of the biphenyl scaffold.

Position 5 seems to be responsible for the agonist or inverse agonist behaviour independently of the substituent in position 4′, with the exception of the methoxyl group which transforms both full agonists and inverse agonists into neutral antagonists.

This study provides a novel complete toolbox of CB2 functional modulators that derive from the same chemical scaffold. Such probes may be useful to investigate the biological role of CB2 receptors in cellular assays.”

http://www.ncbi.nlm.nih.gov/pubmed/27078864

Production of endocannabinoids by activated T cells and B cells modulates inflammation associated with delayed type hypersensitivity.

“Endocannabinoids are endogenous ligands for the cannabinoid (CB) receptors which include anandamide (AEA) and (2-AG). 2-AG has been linked to inflammation due to its elevated expression in animal models of autoimmunity and hypersensitivity.

However, administration of exogenous 2-AG has been shown to suppress inflammation making its precise role unclear. In the current study, we investigated the role of 2-AG following immunization of C57BL/6 (BL6) mice with methylated BSA (mBSA) antigen, which triggers both delayed type hypersensitivity (DTH) and antibody response.

Together, these data show for the first time that activated T and B cells produce 2-AG, which plays a negative regulatory role to decrease DTH via inhibition of T-cell activation and proliferation.

Moreover, these findings suggest that exogenous 2-AG treatment can be used therapeutically in Th1- or Th17-driven disease.”  http://www.ncbi.nlm.nih.gov/pubmed/27064137

“∆9-Tetrahydrocannabinol (THC) is one of the major bioactive cannabinoids derived from the Cannabis sativa plant and is known for its anti-inflammatory properties. Delayed-type hypersensitivity (DTH) is driven by proinflammatory T helper cells including the classic inflammatory Th1 lineage as well as the more recently discovered Th17 lineage. In the current study, we investigated whether THC can alter the induction of Th1/Th17 cells involved in mBSA-induced DTH response… In summary, the current study suggests that THC treatment during DTH response can simultaneously inhibit Th1/Th17 activation via regulation of microRNA (miRNA) expression.• THC treatment inhibits simultaneous Th1/Th17 driven inflammation. • THC treatment corrects DTH-mediated microRNA dysregulation. • THC treatment regulates proinflammatory cytokines and transcription factors.” http://www.ncbi.nlm.nih.gov/pubmed/27038180

Role of cannabinoids in gastrointestinal mucosal defense and inflammation.

“Modulating the activity of the endocannabinoid system influences various gastrointestinal physiological and pathophysiological processes, and cannabinoid receptors as well as regulatory enzymes responsible for the synthesis or degradation of endocannabinoids represent potential targets to reduce the development of gastrointestinal mucosal lesions, hemorrhage and inflammation.

Direct activation of CB1 receptors by plant-derived, endogenous or synthetic cannabinoids effectively reduces both gastric acid secretion and gastric motor activity, and decreases the formation of gastric mucosal lesions induced by stress, pylorus ligation, nonsteroidal anti-inflammatory drugs (NSAIDs) or alcohol, partly by peripheral, partly by central mechanisms.

Similarly, indirect activation of cannabinoid receptors through elevation of endocannabinoid levels by globally acting or peripherally restricted inhibitors of their metabolizing enzymes (FAAH, MAGL) or by inhibitors of their cellular uptake reduced the gastric mucosal lesions induced by NSAIDs in a CB1 receptor-dependent fashion.

Dual inhibition of FAAH and cyclooxygenase induced protection against both NSAID-induced gastrointestinal damage and intestinal inflammation.

Moreover, in intestinal inflammation direct or indirect activation of CB1 and CB2 receptors exerts also multiple beneficial effects.

Namely, activation of both CB receptors was shown to ameliorate intestinal inflammation in various murine colitis models, to decrease visceral hypersensitivity and abdominal pain, as well as to reduce colitis-associated hypermotility and diarrhea.

In addition, CB1 receptors suppress secretory processes and also modulate intestinal epithelial barrier functions. Thus, experimental data suggest that the endocannabinoid system represents a promising target in the treatment of inflammatory bowel diseases, and this assumption is also confirmed by preliminary clinical studies.”

http://www.ncbi.nlm.nih.gov/pubmed/26935536

Cannabinoids and autoimmune diseases: A systematic review.

“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/

Selective Cannabinoid Receptor-1 Agonists Regulate Mast Cell Activation in an Oxazolone-Induced Atopic Dermatitis Model.

“Many inflammatory mediators, including various cytokines (e.g. interleukins and tumor necrosis factor [TNF]), inflammatory proteases, and histamine are released following mast cell activation.

Endogenous cannabinoids such as palmitoylethanolamide (PEA) and N-arachidonoylethanolamine (anandamide or AEA), were found in peripheral tissues and have been proposed to possess autacoid activity, implying that cannabinoids may downregulate mast cell activation and local inflammation.

Our results indicate that CB1R agonists down-regulate mast cell activation and may be used for relieving inflammatory symptoms mediated by mast cell activation, such as atopic dermatitis, psoriasis, and contact dermatitis.”

http://www.ncbi.nlm.nih.gov/pubmed/26848215

RGS proteins as targets in the treatment of intestinal inflammation and visceral pain: New insights and future perspectives.

“Regulators of G protein signaling (RGS) proteins provide timely termination of G protein-coupled receptor (GPCR) responses. Serving as a central control point in GPCR signaling cascades, RGS proteins are promising targets for drug development. In this review, we discuss the involvement of RGS proteins in the pathophysiology of the gastrointestinal inflammation and their potential to become a target for anti-inflammatory drugs. Specifically, we evaluate the emerging evidence for modulation of selected receptor families: opioid, cannabinoid and serotonin by RGS proteins. We discuss how the regulation of RGS protein level and activity may modulate immunological pathways involved in the development of intestinal inflammation. Finally, we propose that RGS proteins may serve as a prognostic factor for survival rate in colorectal cancer. The ideas introduced in this review set a novel conceptual framework for the utilization of RGS proteins in the treatment of gastrointestinal inflammation, a growing major concern worldwide.”

http://www.ncbi.nlm.nih.gov/pubmed/26817719

Dietary Supplement Therapies for Inflammatory Bowel Disease: Crohn’s Disease and Ulcerative Colitis.

“Inflammatory bowel disease (IBD) including ulcerative colitis and Crohn’s disease are chronic relapsing and remitting chronic diseases for which there is no cure.

The treatment of IBD frequently requires immunosuppressive and biologic therapies which carry an increased risk of infections and possible malignancy.

There is a continued search for safer and more natural therapies in the treatment of IBD.

This review aims to summarize the most current literature on the use of dietary supplements for the treatment of IBD. Specifically, the efficacy and adverse effects of vitamin D, fish oil, probiotics, prebiotics, curcumin, Boswellia serrata, aloe vera and cannabis sativa are reviewed.”

http://www.ncbi.nlm.nih.gov/pubmed/26561079

HU-444, A Novel, Potent Anti-Inflammatory, Non-Psychotropic Cannabinoid.

“Cannabidiol (CBD) is a component of cannabis, which does not cause the typical marijuana-type effects, but has a high potential for use in several therapeutic areas.

In contrast to Δ9-tetrahydrocannabinol (Δ9-THC) it binds very weakly to the CB1 and CB2 cannabinoid receptors. It has potent activity in both in vitro and in vivo anti-inflammatory assays. Thus, it lowers the formation of TNF-α, a proinflammatory cytokine, and was found to be an oral anti-arthritic therapeutic in murine collagen-induced arthritis in vivo.

However in acidic media it can cyclize to the psychoactive Δ9-THC. We report the synthesis of a novel CBD derivative, HU-444, which cannot be converted by acid cyclization into a Δ9-THC-like compound.

In vitro HU-444 had anti-inflammatory activity (decrease of reactive oxygen intermediates and inhibition of TNF-a production by macrophages); in vivo it led to suppression of production of TNF-α and amelioration of liver damage as well as lowering of mouse collagen-induced arthritis. HU-444 did not cause Δ9-THC- like effects in mice.

We believe that HU-444 represents a potential novel drug for rheumatoid arthritis and other inflammatory diseases.”

http://www.ncbi.nlm.nih.gov/pubmed/26272937