The Endocannabinoid System: A Potential Target for the Treatment of Various Diseases

ijms-logo“The Endocannabinoid System (ECS) is primarily responsible for maintaining homeostasis, a balance in internal environment (temperature, mood, and immune system) and energy input and output in living, biological systems.

In addition to regulating physiological processes, the ECS directly influences anxiety, feeding behaviour/appetite, emotional behaviour, depression, nervous functions, neurogenesis, neuroprotection, reward, cognition, learning, memory, pain sensation, fertility, pregnancy, and pre-and post-natal development.

The ECS is also involved in several pathophysiological diseases such as cancer, cardiovascular diseases, and neurodegenerative diseases. In recent years, genetic and pharmacological manipulation of the ECS has gained significant interest in medicine, research, and drug discovery and development.

The distribution of the components of the ECS system throughout the body, and the physiological/pathophysiological role of the ECS-signalling pathways in many diseases, all offer promising opportunities for the development of novel cannabinergic, cannabimimetic, and cannabinoid-based therapeutic drugs that genetically or pharmacologically modulate the ECS via inhibition of metabolic pathways and/or agonism or antagonism of the receptors of the ECS. This modulation results in the differential expression/activity of the components of the ECS that may be beneficial in the treatment of a number of diseases.

This manuscript in-depth review will investigate the potential of the ECS in the treatment of various diseases, and to put forth the suggestion that many of these secondary metabolites of Cannabis sativa L. (hereafter referred to as “C. sativa L.” or “medical cannabis”), may also have potential as lead compounds in the development of cannabinoid-based pharmaceuticals for a variety of diseases.”

https://pubmed.ncbi.nlm.nih.gov/34502379/

https://www.mdpi.com/1422-0067/22/17/9472

 

“Cannabis sativa L. as a Natural Drug Meeting the Criteria of a Multitarget Approach to Treatment”

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7830475/

Gastrointestinal Adverse Events of Cannabinoid 1 Receptor Inverse Agonists suggest their Potential Use in Irritable Bowel Syndrome with Constipation: A Systematic Review and Meta-Analysis.

 Image result for J Gastrointestin Liver Dis“Irritable bowel syndrome (IBS) is one of the most common functional gastrointestinal (GI) disorders characterized by pain and impaired bowel movements. Currently available drugs show limited efficacy.

Cannabinoid 1 receptor (CB1) inverse agonists (CB1-RAN) cause diarrhea and may be candidates for the treatment of constipation-predominant IBS (IBS-C). We evaluated the effects of CB1-RAN in clinical trials for their potential use in IBS-C.

METHODS:

Database search identified all clinical trials published up to May 2018 that reported rimonabant and taranabant treatment for at least one month and detailed the GI adverse events (AEs). Categorical outcomes (subgroups of AEs) were analyzed using the odds ratio (OR).

RESULTS:

Eighteen trials met the inclusion criteria. Rimonabant 20 mg produced significantly more overall AEs (OR=1.35, CI: 1.19-1.52, p<0.0001), psychiatric events (OR=1.79, CI: 1.46-2.21, p<0.001) and GI AEs (OR=2.05, CI: 1.65-2.55, p<0.001) compared to placebo. Taranabant at doses ranging from 0.5 to 8 mg produced significantly more overall AEs (OR=1.36, CI: 1.13-1.64, p<0.002), psychiatric AEs (1.82, CI: 1.54-2.16, p<0.001) and GI AEs (OR=1.75, CI: 1.29-2.37, p<0.001) compared to placebo.

CONCLUSIONS:

The approach to target CB1 in the gut for the treatment of IBS-C or chronic constipation seems a promising therapeutic option. Prospective clinical trials on the possible targeting of CB1 and the endocannabinoid system are warranted.”

https://www.ncbi.nlm.nih.gov/pubmed/31826058

https://www.jgld.ro/jgld/index.php/jgld/article/view/265

Nabilone administration in refractory chronic diarrhea: a case series

Image result for bmc gastroenterology
“Through the years, the endocannabinoid system has been recognized in the homeostatic mechanisms of the gut, as well as in the physiological control of intestinal motility and secretion. Accordingly, cannabinoids may be a promising therapy against several gastrointestinal conditions, such as abdominal pain and motility-related disorders. After three months of therapy, oral nabilone improved the health of nearly all patients, with visible improvements in reducing diarrheal symptoms and weight gain. These findings encourage the study of cannabinoids acting on CB1 receptors in chronic gastrointestinal disorders, especially in refractory chronic diarrhea, offering a chance for a substantial improvement in the quality of life of selected patients, with a reasonable safety profile.” https://bmcgastroenterol.biomedcentral.com/articles/10.1186/s12876-019-1024-y
“Nabilone is a drug used to treat severe nausea and vomiting. It is in a family of drugs called cannabinoids (eg. marijuana).” https://hivclinic.ca/main/drugs_fact_files/nabilone.pdf

The novel peripherally active cannabinoid type 1 and serotonin type 3 receptor agonist AM9405 inhibits gastrointestinal motility and reduces abdominal pain in mouse models mimicking irritable bowel syndrome.

European Journal of Pharmacology

“The endocannabinoid system (ECS) plays a crucial role in numerous physiological processes in the central and peripheral nervous systems. In the gastrointestinal (GI) tract, selective cannabinoid (CB) receptor agonists exert potent inhibitory actions on motility and pain signalling. In the present study, we used mouse models of diarrhea, hypermotility, and abdominal pain to examine whether a novel synthetic CB1 receptor agonist AM9405 [(2-(2,6-dihydroxy-4-(2-methyloctan-2-yl)phenyl)-1,3-dimethyl-1H-benzo[d]imidazol-3-ium bromide); also known as GAT379] exhibits effects of potential therapeutic relevance. AM9405 significantly slowed mouse intestinal motility in physiological conditions. Moreover, AM9405 reversed hypermotility and reduced pain in mouse models mimicking symptoms of functional GI disorders, such as stress-induced diarrhoea and writhing test. Interestingly, some of the effects of AM9405 were blocked by a 5-HT3 antagonist suggesting interaction with 5-HT3 receptors. In our study we show that combining CB1 agonism with 5-HT3 agonism may alter physiological functions and experimental pathophysiologies in a manner that make such compounds promising drugs for the future treatment of functional GI disorders.”

https://www.ncbi.nlm.nih.gov/pubmed/30121173

https://www.sciencedirect.com/science/article/pii/S0014299918304734?via%3Dihub

Cannabinoid pharmacology and therapy in gut disorders.

Biochemical Pharmacology

“Cannabis sp and their products (marijuana, hashish…), in addition to their recreational, industrial and other uses, have a long history for their use as a remedy for symptoms related with gastrointestinal diseases.

After many reports suggesting these beneficial effects, it was not surprising to discover that the gastrointestinal tract expresses endogenous cannabinoids, their receptors, and enzymes for their synthesis and degradation, comprising the so-called endocannabinoid system.

This system participates in the control of tissue homeostasis and important intestinal functions like motor and sensory activity, nausea, emesis, the maintenance of the epithelial barrier integrity, and the correct cellular microenvironment. Thus, different cannabinoid-related pharmacological agents may be useful to treat the main digestive pathologies.

To name a few examples, in irritable bowel syndrome they may normalize dysmotility and reduce pain, in inflammatory bowel disease they may decrease inflammation, and in colorectal cancer, apart from alleviating some symptoms, they may play a role in the regulation of the cell niche.

This review summarizes the main recent findings on the role of cannabinoid receptors, their synthetic or natural ligands and their metabolizing enzymes in normal gastrointestinal function and in disorders including irritable bowel syndrome, inflammatory bowel disease, colon cancer and gastrointestinal chemotherapy-induced adverse effects (nausea/vomiting, constipation, diarrhea).”

Cannabidiol restores intestinal barrier dysfunction and inhibits the apoptotic process induced by Clostridium difficile toxin A in Caco-2 cells.

 SAGE Journals

“Clostridium difficile toxin A is responsible for colonic damage observed in infected patients.

Drugs able to restore Clostridium difficile toxin A-induced toxicity have the potential to improve the recovery of infected patients. Cannabidiol is a non-psychotropic component of Cannabis sativa, which has been demonstrated to protect enterocytes against chemical and/or inflammatory damage and to restore intestinal mucosa integrity.

The purpose of this study was to evaluate (a) the anti-apoptotic effect and (b) the mechanisms by which cannabidiol protects mucosal integrity in Caco-2 cells exposed to Clostridium difficile toxin A.

RESULTS:

Clostridium difficile toxin A significantly decreased Caco-2 cells’ viability and reduced transepithelial electrical resistence values and RhoA guanosine triphosphate (GTP), bax, zonula occludens-1 and occludin protein expression, respectively. All these effects were significantly and concentration-dependently inhibited by cannabidiol, whose effects were completely abolished in the presence of the cannabinoid receptor type 1 (CB1) antagonist, AM251.

CONCLUSIONS:

Cannabidiol improved Clostridium difficile toxin A-induced damage in Caco-2 cells, by inhibiting the apoptotic process and restoring the intestinal barrier integrity, through the involvement of the CB1 receptor.”

https://www.ncbi.nlm.nih.gov/pubmed/29238589

“In the last decade, cannabinoids extracted from the marijuana plant (Cannabis sativa) and synthetic cannabinoids have shown numerous beneficial effects on gastrointestinal (GI) functions. Non-psychotropic phytocannabinoid cannabidiol (CBD) is one of the most interesting compounds, since it exerts a wide range of beneficial pharmacological actions on GI functions, ranging from antioxidant to antinflammatory activities. CBD has been shown to act as a non-competitive negative allosteric modulator of CB1 receptors. Notably, CBD is able to restore in vitro intestinal permeability increased by ethylenediaminetetraacetic acid (EDTA) or pro-inflammatory stimuli.

Clostridium difficile infection is the leading cause of hospital-acquired diarrhoea and pseudomembranous colitis. Clostridium difficile-Toxin A significantly affects enterocytes permeability leading to apoptosis and colonic mucosal damage.

In the present study, we showed that Cannabidiol, a non-psychotropic component of Cannabis sativa significantly inhibit the apoptosis rate in TcdA-exposed cells and restores barrier function by a significant RhoA GTP rescue.

We also provide evidence that the effects of Cannabidiol are mediated by CB-1 receptor.

Given the absence of any significant toxic effect in humans, cannabidiol may ideally represent an effective adjuvant treatment for Clostridium difficile-associated colitis.”   http://journals.sagepub.com/doi/10.1177/2050640617698622

Cannabinoids for treating inflammatory bowel diseases: where are we and where do we go?

Image result for Expert Rev Gastroenterol Hepatol.

“Fifty years after the discovery of Δ9-tetrahydrocannabinol (THC) as the psychoactive component of Cannabis, we are assessing the possibility of translating this herb into clinical treatment of inflammatory bowel diseases (IBDs).

Here, a discussion on the problems associated with a potential treatment is given.

From first surveys and small clinical studies in patients with IBD we have learned that Cannabis is frequently used to alleviate diarrhea, abdominal pain, and loss of appetite.

Single ingredients from Cannabis, such as THC and cannabidiol, commonly described as cannabinoids, are responsible for these effects. Synthetic cannabinoid receptor agonists are also termed cannabinoids, some of which, like dronabinol and nabilone, are already available with a narcotic prescription.

Recent data on the effects of Cannabis/cannabinoids in experimental models of IBD and in clinical trials with IBD patients have been reviewed using a PubMed database search. A short background on the endocannabinoid system is also provided.

Expert commentary: Cannabinoids could be helpful for certain symptoms of IBD, but there is still a lack of clinical studies to prove efficacy, tolerability and safety of cannabinoid-based medication for IBD patients, leaving medical professionals without evidence and guidelines.”

Cannabinoids as gastrointestinal anti-inflammatory drugs.

Related image

“In this mini-review, we focus on the potential of the endocannabinoid system as a target for novel therapies to treat gastrointestinal (GI) inflammation. We discuss the organization of the endocannabinoid signaling and present possible pharmacological sites in the endocannabinoid system. We also refer to recent clinical findings in the field. Finally, we point at the potential use of cannabinoids at low, non-psychoactive doses to counteract non-inflammatory pathological events in the GI tract, like chemotherapy-induced diarrhea, as evidenced by Abalo et al. in the rat model.”

https://www.ncbi.nlm.nih.gov/pubmed/28239924

Role of cannabis in digestive disorders.

Image result for European Journal of Gastroenterology & Hepatology

“Cannabis sativa, a subspecies of the Cannabis plant, contains aromatic hydrocarbon compounds called cannabinoids.

Tetrahydrocannabinol is the most abundant cannabinoid and is the main psychotropic constituent.

Cannabinoids activate two types of G-protein-coupled cannabinoid receptors: cannabinoid type 1 receptor and cannabinoid type 2 receptor.

There has been ongoing interest and development in research to explore the therapeutic potential of cannabis. Tetrahydrocannabinol exerts biological functions on the gastrointestinal (GI) tract.

Cannabis has been used for the treatment of GI disorders such as abdominal pain and diarrhea.

The endocannabinoid system (i.e. endogenous circulating cannabinoids) performs protective activities in the GI tract and presents a promising therapeutic target against various GI conditions such as inflammatory bowel disease (especially Crohn’s disease), irritable bowel syndrome, and secretion and motility-related disorders.

The present review sheds light on the role of cannabis in the gut, liver, and pancreas and also on other GI symptoms, such as nausea and vomiting, cannabinoid hyperemesis syndrome, anorexia, weight loss, and chronic abdominal pain.

Although the current literature supports the use of marijuana for the treatment of digestive disorders, the clinical efficacy of cannabis and its constituents for various GI disorders remains unclear.”

https://www.ncbi.nlm.nih.gov/pubmed/27792038

May cannabinoids prevent the development of chemotherapy-induced diarrhea and intestinal mucositis? Experimental study in the rat.

Image result for neurogastroenterology & motility

“The antineoplastic drug 5-fluoruracil (5-FU) is a pirimidine analog, which frequently induces potentially fatal diarrhea and mucositis.

Cannabinoids reduce gastrointestinal motility and secretion and might prevent 5-FU-induced gut adverse effects.

Here, we asked whether cannabinoids may prevent diarrhea and mucositis induced by 5-FU in the rat.

CONCLUSIONS AND INFERENCES:

5-FU-induced diarrhea, but not mucositis, was partly prevented by WIN at a low dose.

Cannabinoids might be useful to prevent chemotherapy-induced diarrhea.”

https://www.ncbi.nlm.nih.gov/pubmed/27686064