Cannabis and the Gastrointestinal Tract

“Cannabis has been used for its medicinal purposes since ancient times. Its consumption leads to the activation of Cannabis receptors CB1 and CB2 that, through specific mechanisms can lead to modulation and progression of inflammation or repair. The novel findings are linked to the medical use of Cannabis in gastrointestinal (GI) system.

Purpose: The objective of the present paper is to elucidate the role of Cannabis consumption in GI system. An additional aim is to review the information on the function of Cannabis in non-alcoholic fatty liver disease (NAFLD).

Methods and results: This review summarizes the recent findings on the role of cannabinoid receptors, their synthetic or natural ligands, as well as their metabolizing enzymes in normal GI function and its disorders, including irritable bowel syndrome (IBS), inflammatory bowel disease (IBD) and possible adverse events. The synergism or antagonism between Cannabis’ active ingredients and the “entourage” plays a role in the efficacy of various strains. Some elements of Cannabis may alter disease severity as over-activation of Cannabis receptors CB1 and CB2 can lead to changes of the commensal gut flora. The endocannabinoid system (ECS) contributes to gut homeostasis. The ability of ECS to modulate inflammatory responses demonstrates the capacity of ECS to preserve gastrointestinal (GI) function. Alterations of the ECS may predispose patients to pathologic disorders, including IBD. Clinical studies in IBD demonstrate that subjects benefit from Cannabis consumption as seen through a reduction of the IBD-inflammation, as well as through a decreased need for other medication. NAFLD is characterized by fat accumulation in the liver. The occurrence of inflammation in NAFLD leads to non-alcoholic-steatohepatitis (NASH). The use of Cannabis might reduce liver inflammation.

Conclusions: With limited evidence of efficacy and safety of Cannabis in IBD, IBS, and NAFLD, randomized controlled studies are required to examine its therapeutic efficacy.”

https://pubmed.ncbi.nlm.nih.gov/32762830/

https://journals.library.ualberta.ca/jpps/index.php/JPPS/article/view/31242

Cannabis Improves Obsessive-Compulsive Disorder-Case Report and Review of the Literature

Archive of "Frontiers in Psychiatry". “Although several lines of evidence support the hypothesis of a dysregulation of serotoninergic neurotransmission in the pathophysiology of obsessive-compulsive disorder (OCD), there is also evidence for an involvement of other pathways such as the GABAergic, glutamatergic, and dopaminergic systems.

Only recently, data obtained from a small number of animal studies alternatively suggested an involvement of the endocannabinoid system in the pathophysiology of OCD reporting beneficial effects in OCD-like behavior after use of substances that stimulate the endocannabinoid system.

In humans, until today, only two case reports are available reporting successful treatment with dronabinol (tetrahydrocannabinol, THC), an agonist at central cannabinoid CB1 receptors, in patients with otherwise treatment refractory OCD. In addition, data obtained from a small open uncontrolled trial using the THC analogue nabilone suggest that the combination of nabilone plus exposure-based psychotherapy is more effective than each treatment alone.

These reports are in line with data from a limited number of case studies and small controlled trials in patients with Tourette syndrome (TS), a chronic motor and vocal tic disorder often associated with comorbid obsessive compulsive behavior (OCB), reporting not only an improvement of tics, but also of comorbid OCB after use of different kinds of cannabis-based medicines including THC, cannabis extracts, and flowers.

Here we present the case of a 22-year-old male patient, who suffered from severe OCD since childhood and significantly improved after treatment with medicinal cannabis with markedly reduced OCD and depression resulting in a considerable improvement of quality of life. In addition, we give a review of current literature on the effects of cannabinoids in animal models and patients with OCD and suggest a cannabinoid hypothesis of OCD.”

https://pubmed.ncbi.nlm.nih.gov/32848902/

https://www.frontiersin.org/articles/10.3389/fpsyt.2020.00681/full

Cannabinoids for People with ASD: A Systematic Review of Published and Ongoing Studies

brainsci-logo“The etiopathogenesis of autism spectrum disorder (ASD) remains largely unclear.

Among other biological hypotheses, researchers have evidenced an imbalance in the endocannabinoid (eCB) system, which regulates some functions typically impaired in ASD, such as emotional responses and social interaction. Additionally, cannabidiol (CBD), the non-intoxicating component of Cannabis sativa, was recently approved for treatment-resistant epilepsy.

Epilepsy represents a common medical condition in people with ASD. Additionally, the two conditions share some neuropathological mechanisms, particularly GABAergic dysfunctions. Hence, it was hypothesized that cannabinoids could be useful in improving ASD symptoms.

The findings were promising, as cannabinoids appeared to improve some ASD-associated symptoms, such as problem behaviors, sleep problems, and hyperactivity, with limited cardiac and metabolic side effects. Conversely, the knowledge of their effects on ASD core symptoms is scarce.

Interestingly, cannabinoids generally allowed to reduce the number of prescribed medications and decreased the frequency of seizures in patients with comorbid epilepsy. Mechanisms of action could be linked to the excitatory/inhibitory imbalance found in people with ASD. However, further trials with better characterization and homogenization of samples, and well-defined outcomes should be implemented.”

https://pubmed.ncbi.nlm.nih.gov/32825313/

https://www.mdpi.com/2076-3425/10/9/572

Role of cannabinoids in alcohol-induced neuroinflammation

 Progress in Neuro-Psychopharmacology and Biological Psychiatry“Alcohol is a psychoactive substance highly used worldwide, whose harmful use might cause a broad range of mental and behavioural disorders. Underlying brain impact, the neuroinflammatory response induced by alcohol is recognised as a key contributing factor in the progression of other neuropathological processes, such as neurodegeneration. These sequels are determined by multiple factors, including age of exposure.

Strikingly, it seems that the endocannabinoid system modulation could regulate the alcohol-induced neuroinflammation. Although direct CB1 activation can worsen alcohol consequences, targeting other components of the expanded endocannabinoid system may counterbalance the pro-inflammatory response.

Indeed, specific modulations of the expanded endocannabinoid system have been proved to exert anti-inflammatory effects, primarily through the CB2 and PPARγ signalling. Among them, some endo- and exogeneous cannabinoids can block certain pro-inflammatory mediators, such as NF-κB, thereby neutralizing the neuroinflammatory intracellular cascades.

Furthermore, a number of cannabinoids are able to activate complementary anti-inflammatory pathways, which are necessary for the transition from chronically overactivated microglia to a regenerative microglial phenotype. Thus, cannabinoid modulation provides cooperative anti-inflammatory mechanisms that may be advantageous to resolve a pathological neuroinflammation in an alcohol-dependent context.”

https://pubmed.ncbi.nlm.nih.gov/32758518/

“Cannabinoid modulation represents an extremely interesting therapeutic target in alcohol-induced chronic neuroinflammation.”

https://www.sciencedirect.com/science/article/pii/S0278584620303705?via%3Dihub

Fig. 1

The Treatment of Cognitive, Behavioural and Motor Impairments from Brain Injury and Neurodegenerative Diseases through Cannabinoid System Modulation-Evidence from In Vivo Studies

jcm-logo“Neurological disorders such as neurodegenerative diseases or traumatic brain injury are associated with cognitive, motor and behavioural changes that influence the quality of life of the patients. Although different therapeutic strategies have been developed and tried until now to decrease the neurological decline, no treatment has been found to cure these pathologies.

In the last decades, the implication of the endocannabinoid system in the neurological function has been extensively studied, and the cannabinoids have been tried as a new promising potential treatment. In this study, we aimed to overview the recent available literature regarding in vivo potential of natural and synthetic cannabinoids with underlying mechanisms of action for protecting against cognitive decline and motor impairments.

The results of studies on animal models showed that cannabinoids in traumatic brain injury increase neurobehavioral function, working memory performance, and decrease the neurological deficit and ameliorate motor deficit through down-regulation of pro-inflammatory markers, oedema formation and blood-brain barrier permeability, preventing neuronal cell loss and up-regulating the levels of adherence junction proteins.

In neurodegenerative diseases, the cannabinoids showed beneficial effects in decreasing the motor disability and disease progression by a complex mechanism targeting more signalling pathways further than classical receptors of the endocannabinoid system. In light of these results, the use of cannabinoids could be beneficial in traumatic brain injuries and multiple sclerosis treatment, especially in those patients who display resistance to conventional treatment.”

https://pubmed.ncbi.nlm.nih.gov/32726998/

https://www.mdpi.com/2077-0383/9/8/2395

Anti-Cancer Potential of Cannabinoids, Terpenes, and Flavonoids Present in Cannabis

cancers-logo“In recent years, and even more since its legalization in several jurisdictions, cannabis and the endocannabinoid system have received an increasing amount of interest related to their potential exploitation in clinical settings. Cannabinoids have been suggested and shown to be effective in the treatment of various conditions. In cancer, the endocannabinoid system is altered in numerous types of tumours and can relate to cancer prognosis and disease outcome. Additionally, cannabinoids display anticancer effects in several models by suppressing the proliferation, migration and/or invasion of cancer cells, as well as tumour angiogenesis. However, the therapeutic use of cannabinoids is currently limited to the treatment of symptoms and pain associated with chemotherapy, while their potential use as cytotoxic drugs in chemotherapy still requires validation in patients. Along with cannabinoids, cannabis contains several other compounds that have also been shown to exert anti-tumorigenic actions. The potential anti-cancer effects of cannabinoids, terpenes and flavonoids, present in cannabis, are explored in this literature review.”

https://pubmed.ncbi.nlm.nih.gov/32708138/

https://www.mdpi.com/2072-6694/12/7/1985

Pharmacological activation of CB2 receptor protects against ethanol-induced myocardial injury related to RIP1/RIP3/MLKL-mediated necroptosis

 Molecular and Cellular Biochemistry | Home“Chronic ethanol abuse can lead to harmful consequences for the heart, resulting in systolic dysfunction, variability in the heart rate, arrhythmia, and cardiac remodelling. However, the precise molecular mechanism responsible for ethanol-induced cardiomyopathy is poorly understood. In this regard, the present study aimed to describe the RIP1/RIP3/MLKL-mediated necroptotic cell death that may be involved in ethanol-induced cardiomyopathy and characterize CBR-mediated effects on the signalling pathway and myocardial injury.

We performed an ethanol vapour administration experiment to analyse the effects of ethanol on cardiac structure and function in male C57BL/6J mice. Ethanol induced a significant decline in the cardiac structure and function, as evidenced by a decline in ejection fraction and fractional shortening, and an increase in serum Creatine Kinase levels, myocardial collagen content, and inflammatory reaction. Furthermore, ethanol also upregulated the expression levels of necroptosis-related markers such as p-RIP1, p-RIP3, and p-MLKL in the myocardium. Nec-1 treatment exerted significant cardioprotective effects by salvaging the heart tissue, improving the cardiac function, and mitigating inflammation and necroptosis.

In addition, ethanol abuse caused an imbalance in the endocannabinoid system and regulated two cannabinoid receptors (CB1R and CB2R) in the myocardium. Treatment with selective CB2R agonists, JWH-133 or AM1241, markedly improved the cardiac dysfunction and reduced the ethanol-induced necroptosis in the myocardium.

Altogether, our data provide evidence that ethanol abuse-induced cardiotoxicity can possibly be attributed to the RIP1/RIP3/MLKL-mediated necroptosis. Moreover, pharmacological activation of CB2R may represent a new cardioprotective strategy against ethanol-induced cardiotoxicity.”

https://pubmed.ncbi.nlm.nih.gov/32681290/

https://link.springer.com/article/10.1007%2Fs11010-020-03828-1

Naturally Occurring Cannabinoids and their Role in Modulation of Cardiovascular Health

 Publication Cover“In recent years, the role of the endocannabinoid system (ECS) in various cardiovascular conditions has been a subject of great interest. The ECS is composed of cannabinoid receptors, their endogenous ligands, also known as endocannabinoids, and enzymes responsible for the synthesis and degradation of endocannabinoids.

Several lines of evidence suggest that the ECS plays a complex role in cardiac and vascular systems; however, under normal physiological conditions the functions of the ECS are limited. Overactivation of components of the ECS has been associated with various cardiovascular conditions.

Intriguingly, activation of the ECS may also reflect a cardioprotective compensatory mechanism. With this knowledge, a range of naturally occurring and synthetic cannabinoid receptor agonists and antagonists, as well as inhibitors of endocannabinoid metabolic enzymes have emerged as promising approaches for the treatment or management of cardiovascular health.

This review will first focus on the known role of the ECS in regulating the cardiovascular system. Secondly, we discuss emerging data highlighting the therapeutic potential of naturally occurring non-psychoactive ECS modulators within the cardiovascular system, including phytocannabinoids, terpenes, and the endocannabinoid-like molecule palmitoylethanolamide.”

https://pubmed.ncbi.nlm.nih.gov/32677481/

“Several approaches discussed here, including administration of eCB-related molecules such as PEA, or supplementing with various phytocannabinoids can be promising candidates for the management of cardiovascular risk factors and CVD.”

https://www.tandfonline.com/doi/full/10.1080/19390211.2020.1790708

The Pro-neurogenic Effects of Cannabidiol and Its Potential Therapeutic Implications in Psychiatric Disorders

Archive of "Frontiers in Behavioral Neuroscience". “During the last decades, researchers have investigated the functional relevance of adult hippocampal neurogenesis in normal brain function as well as in the pathogenesis of diverse psychiatric conditions.

Although the underlying mechanisms of newborn neuron differentiation and circuit integration have yet to be fully elucidated, considerable evidence suggests that the endocannabinoid system plays a pivotal role throughout the processes of adult neurogenesis. Thus, synthetic, and natural cannabinoid compounds targeting the endocannabinoid system have been utilized to modulate the proliferation and survival of neural progenitor cells and immature neurons.

Cannabidiol (CBD), a constituent of the Cannabis Sativa plant, interacts with the endocannabinoid system by inhibiting fatty acid amide hydrolase (FAAH) activity (the rate-limiting enzyme for anandamide hydrolysis), allosterically modulating CB1 and CB2 receptors, and activating components of the “extended endocannabinoid system.” Congruently, CBD has shown prominent pro-neurogenic effects, and, unlike Δ9-tetrahydrocannabinol, it has the advantage of being devoid of psychotomimetic effects.

Here, we first review pre-clinical studies supporting the facilitating effects of CBD on adult hippocampal neurogenesis and available data disclosing cannabinoid mechanisms by which CBD can induce neural proliferation and differentiation. We then review the respective implications for its neuroprotective, anxiolytic, anti-depressant, and anti-reward actions.

In conclusion, accumulating evidence reveals that, in rodents, adult neurogenesis is key to understand the behavioral manifestation of symptomatology related to different mental disorders. Hence, understanding how CBD promotes adult neurogenesis in rodents could shed light upon translational therapeutic strategies aimed to ameliorate psychiatric symptomatology dependent on hippocampal function in humans.”

https://pubmed.ncbi.nlm.nih.gov/32676014/

https://www.frontiersin.org/articles/10.3389/fnbeh.2020.00109/full

The endocannabinoid system

Essays in Biochemistry “Thirty years ago, the discovery of a cannabinoid (CB) receptor that interacts with the psychoactive compound in Cannabis led to the identification of anandamide, an endogenous receptor ligand or endocannabinoid. Research on endocannabinoids has since exploded, and additional receptors along with their lipid mediators and signaling pathways continue to be revealed. Specifically, in humans, the release of endocannabinoids from membrane lipids occurs on demand and the signaling process is rapidly attenuated by the breakdown of the ligand suggesting a tight regulation of the endocannabinoid system (ECS). Additionally, the varying distribution of CB receptors between the central nervous system and other tissues allows for the ECS to participate in a wide range of cognitive and physiological processes. Select plant-derived ‘phyto’cannabinoids such as Δ-9-tetrahydrocannabinol (Δ9-THC) bind to the CB receptors and trigger the ECS, and in the case of Δ9-THC, while it has therapeutic value, can also produce detrimental effects. Current research is aimed at the identification of additional phytocannabinoids with minimal psychotropic effects with potential for therapeutic development. Although decades of research on the ECS and its components have expanded our understanding of the mechanisms and implications of endocannabinoid signaling in mammals, it continues to evolve. Here, we provide a brief overview of the ECS and its overlap with other related lipid-mediated signaling pathways.”

https://pubmed.ncbi.nlm.nih.gov/32648908/

“Therapeutic intervention in the dysregulation of the ECS will no doubt involve new phytocannabinoids and various synthetic CBs with which to control an increasing list of ECS- related pathologies.”

https://portlandpress.com/essaysbiochem/article/doi/10.1042/EBC20190086/225762/The-endocannabinoid-system

Anandamide and 2-AG are the principal endogenous ligands that define the classical endocannabinoid signaling system (ECS).