Spinal cannabinoid CB1 or CB2 receptors activation attenuates mechanical allodynia in streptozotocin-induced diabetic rats

 Behavioural Pharmacology“Diabetes is a chronic disease associated with a high number of complications such as peripheral neuropathy, which causes sensorial disturbances and may lead to the development of diabetic neuropathic pain (DNP). The current treatment for DNP is just palliative and the drugs may cause severe adverse effects, leading to discontinuation of treatment. Thus, new therapeutic targets need to be urgently investigated.

Studies have shown that cannabinoids have promising effects in the treatment of several pathological conditions, including chronic pain.

Thus, we aimed to investigate the acute effect of the intrathecal injection of CB1 or CB2 cannabinoid receptor agonists N-(2-chloroethyl)-5Z, 8Z, 11Z, 14Z-eicosatetraenamide (ACEA) or JWH 133, respectively (10, 30 or 100 μg/rat) on the mechanical allodynia associated with experimental diabetes induced by streptozotocin (60 mg/kg; intraperitoneal) in rats.

Cannabinoid receptor antagonists CB1 AM251 or CB2 AM630 (1 mg/kg) were given before treatment with respective agonists to confirm the involvement of cannabinoid CB1 or CB2 receptors. Rats with diabetes exhibited a significant reduction on the paw mechanical threshold 2 weeks after diabetes induction, having the maximum effect observed 4 weeks after the streptozotocin injection. This mechanical allodynia was significantly improved by intrathecal treatment with ACEA or JWH 133 (only at the higher dose of 100 μg). Pre-treatment with AM251 or AM630 significantly reverted the anti-allodynic effect of the ACEA or JWH 133, respectively.

Considering the clinical challenge that the treatment of DPN represents, this study showed for the first time, that the intrathecal cannabinoid receptors agonists may represent an alternative for the treatment of DNP.”

https://pubmed.ncbi.nlm.nih.gov/32804775/

The interaction between the endocannabinoid system and the renin angiotensin system and its potential implication for COVID-19 infection

 Journal of Cannabis Research | Home“Coronavirus disease 2019 (COVID-19) is spreading fast all around the world with more than fourteen millions of detected infected cases and more than 600.000 deaths by 20th July 2020. While scientist are working to find a vaccine, current epidemiological data shows that the most common comorbidities for patients with the worst prognosis, hypertension and diabetes, are often treated with angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs).

Body: Both ACE inhibitors and ARBs induce overexpression of the angiotensin converting enzyme 2 (ACE-2) receptor, which has been identified as the main receptor used by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to enter into the alveolar cells of the lungs. While cannabinoids are known to reduce hypertension, the studies testing the hypotensive effects of cannabinoids never addressed their effects on ACE-2 receptors. However, some studies have linked the endocannabinoid system (ECS) with the renin angiotensin system (RAS), including a cross-modulation between the cannabinoid receptor 1 (CB1) and angiotensin II levels.

Conclusion: Since there are around 192 million people using cannabis worldwide, we believe that the mechanism underlying the hypotensive properties of cannabinoids should be urgently studied to understand if they can also lead to ACE-2 overexpression as other antihypertensive drugs do.”

https://pubmed.ncbi.nlm.nih.gov/32835160/

https://jcannabisresearch.biomedcentral.com/articles/10.1186/s42238-020-00030-4

Anti-proliferative and cytotoxic effect of cannabidiol on human cancer cell lines in presence of serum

 BMC Research Notes | Home page“Objective: Cannabinoids are able to reduce tumor growth in xenograft models, but their therapeutic potential as anti-cancer drugs in humans is unclear yet. In vitro studies of the effect of cannabinoids on cancer cells are often carried out in absence of serum or in low serum concentration (i.e. 0.5% serum), conditions that limit cellular growth and therefore can increase the response of cells to additional challenges such as the presence of cannabinoids. However, the tumor microenvironment can be teaming with growth factors. In this study we assessed the viability and proliferation of cancer cells treated with cannabidiol in presence of a serum concentration that commonly sustains cell growth (10% serum).

Results: The results show that cannabidiol exerts a markedly different effect on the viability of the human HT-29 cancer cell line when cultured in presence of 0.5% serum in comparison to 10% serum, displaying a cytotoxic effect only in the former situation. In presence of 10% serum, no inhibitory effect of cannabidiol on DNA replication of HT-29 cells was detected, and a weak inhibition was observed for other cancer cell lines. These results indicate that the effect of cannabidiol is cell context-dependent being modulated by the presence of growth factors.”

https://pubmed.ncbi.nlm.nih.gov/32819436/

“The cannabis plant has a therapeutic potential to treat a wide range of diseases, including cancer.”

https://bmcresnotes.biomedcentral.com/articles/10.1186/s13104-020-05229-5

Emerging Promise of Cannabinoids for the Management of Pain and Associated Neuropathological Alterations in Alzheimer’s Disease

Frontiers in Pharmacology (@FrontPharmacol) | Twitter “Alzheimer’s disease (AD) is an irreversible chronic neurodegenerative disorder that occurs when neurons in the brain degenerate and die. Pain frequently arises in older patients with neurodegenerative diseases including AD. However, the presence of pain in older people is usually overlooked with cognitive dysfunctions. Most of the times dementia patients experience moderate to severe pain but the development of severe cognitive dysfunctions tremendously affects their capability to express the presence of pain. Currently, there are no effective treatments against AD that emphasize the necessity for increasing research to develop novel drugs for treating or preventing the disease process. Furthermore, the prospective therapeutic use of cannabinoids in AD has been studied for the past few years. In this regard, targeting the endocannabinoid system has considered as a probable therapeutic strategy to control several associated pathological pathways, such as mitochondrial dysfunction, excitotoxicity, oxidative stress, and neuroinflammation for the management of AD. In this review, we focus on recent studies about the role of cannabinoids for the treatment of pain and related neuropathological changes in AD.”

https://pubmed.ncbi.nlm.nih.gov/32792944/

“Cannabinoids act by targeting several signaling processes, such as pain, abnormal processing of Aβ and tau, neuroinflammation, excitotoxicity, oxidative stress, and mitochondrial dysfunction, which play a pivotal role in the management of AD. Cannabinoids also ameliorate behavioral and cognitive dysfunctions. Therefore, due to these extensive medical uses of cannabinoid compounds, it can be said that targeting the endocannabinoid system can be a promising strategy to develop an effective therapy for the management of AD. Furthermore, cannabinoids may demonstrate a safe and reliable low-cost therapy, with limited side effects.”

https://www.frontiersin.org/articles/10.3389/fphar.2020.01097/full

Structural and Functional Insights into Cannabinoid Receptors

 Trends in Pharmacological Sciences (@TrendsinPharma) | Twitter“Cannabinoid receptors type 1 (CB1) and 2 (CB2) are widely expressed in the human body, and are attractive drug targets in the prevention and management of central nervous system (CNS) and immune system dysfunction, respectively. Recent breakthroughs in the structural elucidation of cannabinoid receptors and their signaling complexes with G proteins, provide the important molecular basis of ligand-receptor interactions, activation and signaling mechanism, which will facilitate the next-generation drug design and the precise modulation of the endocannabinoid system. Here, we provide an overview on the structural features of cannabinoid receptors in different functional states and the diverse ligand binding modes. The major challenges and new strategies for future therapeutic applications targeting the endocannabinoid system (ECS) are also discussed.”

https://pubmed.ncbi.nlm.nih.gov/32739033/

“Cannabinoid receptors as key components of the endocannabinoid system are involved in regulating a variety of physiological and pathological activities, and their ligands are regarded as potential drug candidates for the treatment of many diseases.”

https://www.cell.com/trends/pharmacological-sciences/fulltext/S0165-6147(20)30146-2?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0165614720301462%3Fshowall%3Dtrue

Targeting Cannabinoid Receptors: Current Status and Prospects of Natural Products

ijms-logo “Cannabinoid receptors (CB1 and CB2), as part of the endocannabinoid system, play a critical role in numerous human physiological and pathological conditions. Thus, considerable efforts have been made to develop ligands for CB1 and CB2, resulting in hundreds of phyto- and synthetic cannabinoids which have shown varying affinities relevant for the treatment of various diseases. However, only a few of these ligands are clinically used.

Recently, more detailed structural information for cannabinoid receptors was revealed thanks to the powerfulness of cryo-electron microscopy, which now can accelerate structure-based drug discovery. At the same time, novel peptide-type cannabinoids from animal sources have arrived at the scene, with their potential in vivo therapeutic effects in relation to cannabinoid receptors.

From a natural products perspective, it is expected that more novel cannabinoids will be discovered and forecasted as promising drug leads from diverse natural sources and species, such as animal venoms which constitute a true pharmacopeia of toxins modulating diverse targets, including voltage- and ligand-gated ion channels, G protein-coupled receptors such as CB1 and CB2, with astonishing affinity and selectivity. Therefore, it is believed that discovering novel cannabinoids starting from studying the biodiversity of the species living on planet earth is an uncharted territory.”

https://pubmed.ncbi.nlm.nih.gov/32709050/

https://www.mdpi.com/1422-0067/21/14/5064

Cholesterol regulates cannabinoid analgesia through glycine receptors

Neuropharmacology “Cholesterol plays vital roles in many central physiological and pathological processes. As a key component in the cell membrane, cholesterol can regulate a variety of ion channels, including ligand-gated ion channels (LGICs). However, relatively little is known about the molecular detail and in vivo consequence of cholesterol-LGIC interaction. Here, we reveal that membrane cholesterol depletion significantly inhibits the potentiating effects of dehydroxylcannabidiol (DH-CBD) on glycine-activated currents (IGly) in HEK 293T cells expressing α1/α3 glycine receptors (GlyRs). Simvastatin considerably decreases cholesterol levels and DH-CBD-induced potentiation of IGly in the spinal cord of mice. Simvastatin also significantly decreases DH-CBD analgesia in acute and chronic pain of mice. The cholesterol levels in the dorsal horn of spinal cord, measured by mass spectrometry imaging, are specifically correlated with cannabinoid potentiation of spinal GlyRs and cannabinoid-induced analgesia. These findings suggest that spinal cholesterol is critical for the efficacy of glycinergic cannabinoid-induced analgesia.”

https://pubmed.ncbi.nlm.nih.gov/32712277/

https://www.sciencedirect.com/science/article/abs/pii/S0028390820303105?via%3Dihub

Cannabinoid-profiled agents improve cell survival via reduction of oxidative stress and inflammation, and Nrf2 activation in a toxic model combining hyperglycemia+Aβ 1-42 peptide in rat hippocampal neurons

Neurochemistry International “Alzheimer’s disease (AD) is a multifactorial neurodegenerative disorder linked to various converging toxic mechanisms. Evidence suggests that hyperglycemia induces oxidative stress, mitochondrial dysfunction, inflammation and excitotoxicity, all of which play important roles in the onset and progression of AD pathogenesis.

The endocannabinoid system (ECS) orchestrates major physiological responses, including neuronal plasticity, neuroprotection, and redox homeostasis, to name a few. The multi-targeted effectiveness of the ECS emerges as a potential approach to treat AD.

Here we characterized the protective properties of the endocannabinoids arachidonylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG), the synthetic cannabinoids CP 55-940 and WIN 55,212-2, and the fatty acid amide hydrolase (FAAH) inhibitor URB597, on a combined hyperglycemia+oligomeric amyloid β peptide (Aβ1-42) neurotoxic model in primary hippocampal neurons which exhibit several AD features.

All agents tested preserved cell viability and stimulated mitochondrial membrane potential, while reducing all the evaluated toxic endpoints in a differential manner, with URB597 showing the highest efficacy. The neuroprotective efficacy of all cannabinoid agents, except for URB597, led to partial recruitment of specific antioxidant activity and Nrf2 pathway regulation.

Our results support the neuroprotective potential of these agents at low concentrations against the damaging effects of GLU+Aβ1-42, affording new potential modalities for the design of AD therapies.”

https://pubmed.ncbi.nlm.nih.gov/32781098/

“All cannabinoid agents prevented the GLU + Aβ1-42 toxicity in a differential manner. All cannabinoid agents recruited Nrf2 signaling to protect cells.”

https://www.sciencedirect.com/science/article/abs/pii/S0197018620302084?via%3Dihub

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 use is associated with a lower risk of diabetes in chronic hepatitis C-infected patients (ANRS CO22 Hepather cohort)

 Medscape | J Viral Hepat - Content Listing“Chronic hepatitis C virus (HCV) infection is a risk factor of insulin resistance, and HCV-infected patients are at a high risk of developing diabetes.

In the general population, research has shown the potential benefit of cannabis use for the prevention of diabetes and related metabolic disorders.

We aimed to test whether cannabis use is associated with a lower risk of diabetes in chronic HCV-infected patients.

After multivariable adjustment, current (AOR [95%CI]: 0.49 [0.38-0.63]) and former (0.81 [0.67-0.98], p<.001) cannabis use were both associated with a reduced odds of diabetes. Conversely, male gender, tobacco use, elevated BMI, poverty, being a migrant and advanced fibrosis were associated with increased odds of diabetes. The association between cannabis use and diabetes was maintained in the stratified analysis.

In this large cross-sectional study of chronic HCV-infected patients, cannabis use was associated with a lower risk of diabetes independently of clinical and socio-behavioral factors. Further studies are needed to elucidate a potential causal link and shed light on cannabis compounds and mechanisms involved in this relationship.”

https://pubmed.ncbi.nlm.nih.gov/32810343/