Cannabinoid receptor CB2 protects against balloon-induced neointima formation

Dissecting the role of cannabinoids in vascular health and disease

Cannabis, often recognized as the most widely used illegal psychoactive substance globally, has seen a shift in its legal status in several countries and regions for both recreational and medicinal uses. This change has brought to light new evidence linking cannabis consumption to various vascular conditions. Specifically, there is an association between cannabis use and atherosclerosis, along with conditions such as arteritis, reversible vasospasm, and incidents of aortic aneurysm or dissection. Recent research has started to reveal the mechanisms connecting cannabinoid compounds to atherosclerosis development. It is well known that the primary biological roles of cannabinoids operate through the activation of cannabinoid receptor types 1 and 2. Manipulation of the endocannabinoid system, either genetically or pharmacologically, is emerging as a promising approach to address metabolic dysfunctions related to obesity. Additionally, numerous studies have demonstrated the vasorelaxant properties and potential atheroprotective benefits of cannabinoids. In preclinical trials, cannabidiol is being explored as a treatment option for monocrotaline-induced pulmonary arterial hypertension. Although existing literature suggests a direct role of cannabinoids in the pathogenesis of atherosclerosis, the correlation between cannabinoids and other vascular diseases was only reported in some case series or observational studies, and its role and precise mechanisms remain unclear. Therefore, it is necessary to summarize and update previously published studies. This review article aims to summarize the latest clinical and experimental research findings on the relationship between cannabis use and vascular diseases. It also seeks to shed light on the potential mechanisms underlying these associations, offering a comprehensive view of current knowledge in this evolving field of study.

Exploring the therapeutic potential of natural compounds modulating the endocannabinoid system in various diseases and disorders: review

Cannabinoid receptors, endogenous cannabinoids (endocannabinoids), and the enzymes involved in the biosynthesis and degradation of the endocannabinoids make up the endocannabinoid system (ECS). The components of the ECS are proven to modulate a vast bulk of various physiological and pathological processes due to their abundance throughout the human body. Such discoveries have attracted the researchers' attention and emerged as a potential therapeutical target for the treatment of various diseases. In the present article, we reviewed the discoveries of natural compounds, herbs, herbs formula, and their therapeutic properties in various diseases and disorders by modulating the ECS. We also summarize the molecular mechanisms through which these compounds elicit their properties by interacting with the ECS based on the existing findings. Our study provides the insight into the use of natural compounds that modulate ECS in various diseases and disorders, which in turn may facilitate future studies exploiting natural lead compounds as novel frameworks for designing more effective and safer therapeutics.

Transcriptome-wide analysis reveals the molecular mechanisms of cannabinoid type II receptor agonists in cardiac injury induced by chronic psychological stress

Background: Growing evidence has supported that chronic psychological stress would cause heart damage, However the mechanisms involved are not clear and effective interventions are insufficient. Cannabinoid type 2 receptor (CB2R) can be a potential treatment for cardiac injury. This study is aimed to investigate the protective mechanism of CB2R agonist against chronic psychological stress-induced cardiac injury. Methods: A mouse chronic psychological stress model was constructed based on a chronic unpredictable stress pattern. Mice were performed a three-week psychological stress procedure, and cardiac tissues of them were collected for whole-transcriptome sequencing. Overlap analysis was performed on differentially expressed mRNAs (DE-mRNAs) and ER stress-related genes (ERSRGs), and bioinformatic methods were used to predict the ceRNA networks and conduct pathway analysis. The expressions of the DE-ERSRGs were validated by RT-qPCR. Results: In the comparison of DE mRNA in Case group, Control group and Treatment group, three groups of ceRNA networks and ceRNA (circ) networks were constructed. The DE-mRNAs were mainly enriched in chromatid-relevant terms and Hematopoietic cell lineage pathway. Additionally, 13 DE-ERSRGs were obtained by the overlap analysis, which were utilized to establish a ceRNA network with 15 nodes and 14 edges and a ceRNA (circ) network with 23 nodes and 28 edges. Furthermore, four DE-ERSRGs (Cdkn1a, Atf3, Fkbp5, Gabarapl1) in the networks were key, which were mainly enriched in response to extracellular stimulus, response to nutrient levels, cellular response to external stimulus, and FoxO signaling pathway. Finally, the RT-qPCR results showed almost consistent expression patterns of 13 DE-ERSRGs between the transcriptome and tissue samples. Conclusion: The findings of this study provide novel insights into the molecular mechanisms of chronic psychological stress-induced cardiac diseases and reveal novel targets for the cardioprotective effects of CB2R agonists.

Differential Regulation of MMPs, Apoptosis and Cell Proliferation by the Cannabinoid Receptors CB1 and CB2 in Vascular Smooth Muscle Cells and Cardiac Myocytes

Cannabinoids (CB) are implicated in cardiovascular diseases via the two main receptor subtypes CB₁R and CB₂R. This study investigated whether cannabinoids regulate the activity of matrix metalloproteases (MMP-2, MMP-9) in vascular smooth muscle cells (VSMCs) and in cells of cardiac origin (H9c2 cell line). The influence of CB₁- and CB₂ receptor stimulation or inhibition on cell proliferation, apoptosis and glucose uptake was also evaluated. We used four compounds that activate or block CB receptors: arachidonyl-2-chloroethylamide (ACEA)-CB₁R agonist, rimonabant-CB₁R antagonist, John W. Huffman (JWH133)-CB₂R agonist and CB₂R antagonist-6-Iodopravadoline (AM630). Treatment of cells with the CB₂R agonist JWH133 decreased cytokine activated secretion of proMMP-2, MMP-2 and MMP-9, reduced Fas ligand and caspase-3-mediated apoptosis, normalized the expression of TGF-beta1 and prevented cytokine-induced increase in glucose uptake into the cell. CB₁R inhibition with rimonabant showed similar protective properties as the CB₂R agonist JWH133, but to a lesser extent. In conclusion, CB₁R and CB₂R exert opposite effects on cell glucose uptake, proteolysis and apoptosis in both VSMCs and H9c2 cells. The CB₂R agonist JWH133 demonstrated the highest protective properties. These findings may pave the way to a new treatment of cardiovascular diseases, especially those associated with extracellular matrix degradation.

Cannabinoid receptor 2 activation alleviates diabetes-induced cardiac dysfunction, inflammation, oxidative stress, and fibrosis

Diabetes mellitus promotes accelerated cardiovascular aging and inflammation, which in turn facilitate the development of cardiomyopathy/heart failure. High glucose-induced oxidative/nitrative stress, activation of various pro-inflammatory, and cell death pathways are critical in the initiation and progression of the changes culminating in diabetic cardiomyopathy. Cannabinoid 2 receptor (CB₂R) activation in inflammatory cells and activated endothelium attenuates the pathological changes associated with atherosclerosis, myocardial infarction, stroke, and hepatic cardiomyopathy. In this study, we explored the role of CB₂R signaling in myocardial dysfunction, oxidative/nitrative stress, inflammation, cell death, remodeling, and fibrosis associated with diabetic cardiomyopathy in type 1 diabetic mice. Control human heart left ventricles and atrial appendages, similarly to mouse hearts, had negligible CB₂R expression determine by RNA sequencing or real-time RT-PCR. Diabetic cardiomyopathy was characterized by impaired diastolic and systolic cardiac function, enhanced myocardial CB₂R expression, oxidative/nitrative stress, and pro-inflammatory response (tumor necrosis factor-α, interleukin-1β, intracellular adhesion molecule 1, macrophage inflammatory protein-1, monocyte chemoattractant protein-1), macrophage infiltration, fibrosis, and cell death. Pharmacological activation of CB₂R with a selective agonist attenuated diabetes-induced inflammation, oxidative/nitrative stress, fibrosis and cell demise, and consequent cardiac dysfunction without affecting hyperglycemia. In contrast, genetic deletion of CB₂R aggravated myocardial pathology. Thus, selective activation of CB₂R ameliorates diabetes-induced myocardial tissue injury and preserves the functional contractile capacity of the myocardium in the diabetic milieu. This is particularly encouraging, since unlike CB₁R agonists, CB₂R agonists do not elicit psychoactive activity and cardiovascular side effects and are potential clinical candidates in the treatment of diabetic cardiovascular and other complications.

Cannabinoid Type-2 Receptor Agonist, JWH133 May Be a Possible Candidate for Targeting Infection, Inflammation, and Immunity in COVID-19

The COVID-19 pandemic, caused by SARS-CoV-2, is a deadly disease affecting millions due to the non-availability of drugs and vaccines. The majority of COVID-19 drugs have been repurposed based on antiviral, immunomodulatory, and antibiotic potential. The pathogenesis and advanced complications with infection involve the immune-inflammatory cascade. Therefore, a therapeutic strategy could reduce infectivity, inflammation, and immune modulation. In recent years, modulating the endocannabinoid system, particularly activation of the cannabinoid type 2 (CB2) receptor is a promising therapeutic target for modulation of immune-inflammatory responses. JWH133, a selective, full functional agonist of the CB2 receptor, has been extensively studied for its potent anti-inflammatory, antiviral, and immunomodulatory properties. JWH133 modulates numerous signaling pathways and inhibits inflammatory mediators, including cytokines, chemokines, adhesion molecules, prostanoids, and eicosanoids. In this study, we propose that JWH133 could be a promising candidate for targeting infection, immunity, and inflammation in COVID-19, due to its pharmacological and molecular mechanisms in numerous preclinical efficacy and safety studies, along with its immunomodulatory, anti-inflammatory, organoprotective, and antiviral properties. Thus, JWH133 should be investigated in preclinical and clinical studies for its potential as an agent or adjuvant with other agents for its effect on viremia, infectivity, immune modulation, resolution of inflammation, reduction in severity, and progression of complications in COVID-19. JWH133 is devoid of psychotropic effects due to CB2 receptor selectivity, has negligible toxicity, good bioavailability and druggable properties, including pharmacokinetic and physicochemical effects. We believe that JWH133 could be a promising drug and may inspire further studies for an evidence-based approach against COVID-19.

Pharmacological Properties, Therapeutic Potential and Molecular Mechanisms of JWH133, a CB2 Receptor-Selective Agonist

The endocannabinoid system has attracted attention as a pharmacological target for several pathological conditions. Cannabinoid (CB2)-selective agonists have been the focus of pharmacological studies because modulation of the CB2 receptor (CB2R) can be useful in the treatment of pain, inflammation, arthritis, addiction, and cancer among other possible therapeutic applications while circumventing CNS-related adverse effects. Increasing number of evidences from different independent preclinical studies have suggested new perspectives on the involvement of CB2R signaling in inflammation, infection and immunity, thus play important role in cancer, cardiovascular, renal, hepatic and metabolic diseases. JWH133 is a synthetic agonist with high CB2R selectivity and showed to exert CB2R mediated antioxidant, anti-inflammatory, anticancer, cardioprotective, hepatoprotective, gastroprotective, nephroprotective, and immunomodulatory activities. Cumulative evidences suggest that JWH133 protects against hepatic injury, renal injury, cardiotoxicity, fibrosis, rheumatoid arthritis, and cancer as well as against oxidative damage and inflammation, inhibits fibrosis and apoptosis, and acts as an immunosuppressant. This review provides a comprehensive overview of the polypharmacological properties and therapeutic potential of JWH133. This review also presents molecular mechanism and signaling pathways of JWH133 under various pathological conditions except neurological diseases. Based on the available data, this review proposes the possibilities of developing JWH133 as a promising therapeutic agent; however, further safety and toxicity studies in preclinical studies and clinical trials in humans are warranted.

Role of the Endocannabinoidome in Human and Mouse Atherosclerosis

The Endocannabinoid (eCB) system and its role in many physiological and pathological conditions is well described and accepted, and includes cardiovascular disorders. However, the eCB system has been expanded to an "-ome"; the endocannabinoidome (eCBome) that includes endocannabinoid-related mediators, their protein targets and metabolic enzymes, many of which significantly impact upon cardiometabolic health. These recent discoveries are here summarized with a special focus on their potential involvement in atherosclerosis. We described the role of classical components of the eCB system (eCBs, CB1 and CB2 receptors) and eCB-related lipids, their regulatory enzymes and molecular targets in atherosclerosis. Furthermore, since increasing evidence points to significant cross-talk between the eCBome and the gut microbiome and the gut microbiome and atherosclerosis, we explore the possibility that a gut microbiome - eCBome axis has potential implications in atherosclerosis.

Effect of flaxseed oil supplementation on the erythrocyte membrane fatty acid composition and endocannabinoid system modulation in patients with coronary artery disease: a double-blind randomized controlled trial

Background

The endocannabinoid system (ECS) overactivation, associated with increased inflammatory process, may act as a risk factor for coronary artery disease (CAD). Dietary fat may influence the ECS tone. The aim of the present study was to investigate the effect of flaxseed oil on the erythrocyte membrane fatty acid profile and ECS activity by the measurement of serum N-arachydonoil ethanolamine (AEA) and cannabinoid receptor type-1 (CB1), cannabinoid receptor type-2 (CB2), and fatty acid amide hydrolase (FAAH) mRNA expression.

Methods

This clinical trial was performed on 44 patients with CAD. The intervention group received 1.5% fat milk supplemented with flaxseed oil (containing 2.5 g α-linolenic acid or ALA), while the placebo group received 1.5% fat milk for 10 weeks. The fatty acid profile of erythrocyte membrane phospholipids was measured by gas chromatography. The AEA level was determined using an ELISA kit, and real-time PCR was performed to measure CB1, CB2, and FAAH mRNA expression pre- and post-intervention.

Results

Flaxseed oil supplementation resulted in a significant increase in the ALA content and a significant reduction in linoleic acid (LA) content of membrane phospholipids, compared to the placebo group (MD = − 0.35 and 2.89, respectively; P < 0.05). The within group analysis showed that flaxseed oil supplementation caused a significant reduction in both LA and arachidonic acid (MD = − 4.84 and − 4.03, respectively; P < 0.05) and an elevation in the ALA (MD = 0.37, P < 0.001) content of membrane phospholipids compared with the baseline. In the intervention group, a marked reduction was observed in the serum AEA level after 10 weeks of intervention, compared with the placebo group (MD = 0.64, P = 0.016). Changes in CB2 mRNA expression in the flaxseed oil group were significant (fold change = 1.30, P = 0.003), compared with the placebo group.

Conclusion

Flaxseed oil supplementation could attenuate the ECS tone by decreasing the AEA level and increasing CB2 mRNA expression. Therefore, flaxseed oil may be considered a promising agent with cardioprotective properties.

From Phytocannabinoids to Cannabinoid Receptors and Endocannabinoids: Pleiotropic Physiological and Pathological Roles Through Complex Pharmacology

Apart from having been used and misused for at least four millennia for, among others, recreational and medicinal purposes, the cannabis plant and its most peculiar chemical components, the plant cannabinoids (phytocannabinoids), have the merit to have led humanity to discover one of the most intriguing and pleiotropic endogenous signaling systems, the endocannabinoid system (ECS). This review article aims to describe and critically discuss, in the most comprehensive possible manner, the multifaceted aspects of 1) the pharmacology and potential impact on mammalian physiology of all major phytocannabinoids, and not only of the most famous one Δ9-tetrahydrocannabinol, and 2) the adaptive pro-homeostatic physiological, or maladaptive pathological, roles of the ECS in mammalian cells, tissues, and organs. In doing so, we have respected the chronological order of the milestones of the millennial route from medicinal/recreational cannabis to the ECS and beyond, as it is now clear that some of the early steps in this long path, which were originally neglected, are becoming important again. The emerging picture is rather complex, but still supports the belief that more important discoveries on human physiology, and new therapies, might come in the future from new knowledge in this field.

Nanoparticle-Mediated Targeting of Cyclosporine A Enhances Cardioprotection Against Ischemia-Reperfusion Injury Through Inhibition of Mitochondrial Permeability Transition Pore Opening

Myocardial ischemia-reperfusion (IR) injury limits the therapeutic effects of early reperfusion therapy for acute myocardial infarction (MI), in which mitochondrial permeability transition pore (mPTP) opening plays a critical role. Our aim was to determine whether poly-lactic/glycolic acid (PLGA) nanoparticle-mediated mitochondrial targeting of a molecule that inhibits mPTP opening, cyclosporine A (CsA), enhances CsA-induced cardioprotection. In an in vivo murine IR model, intravenously injected PLGA nanoparticles were located at the IR myocardium mitochondria. Treatment with nanoparticles incorporated with CsA (CsA-NP) at the onset of reperfusion enhanced cardioprotection against IR injury by CsA alone (as indicated by the reduced MI size at a lower CsA concentration) through the inhibition of mPTP opening. Left ventricular remodeling was ameliorated 28 days after IR, but the treatment did not affect inflammatory monocyte recruitment to the IR heart. In cultured rat cardiomyocytes in vitro, mitochondrial PLGA nanoparticle-targeting was observed after the addition of hydrogen peroxide, which represents oxidative stress during IR, and was prevented by CsA. CsA-NP can be developed as an effective mPTP opening inhibitor and may protect organs from IR injury.

Genetic Manipulation of the Endocannabinoid System

The physiological and pathophysiological functions of the endocannabinoid system have been studied extensively using transgenic and targeted knockout mouse models. The first gene deletions of the cannabinoid CB(1) receptor were described in the late 1990s, soon followed by CB(2) and FAAH mutations in early 2000. These mouse models helped to elucidate the fundamental role of endocannabinoids as retrograde transmitters in the CNS and in the discovery of many unexpected endocannabinoid functions, for example, in the skin, bone and liver. We now have knockout mouse models for almost every receptor and enzyme of the endocannabinoid system. Conditional mutant mice were mostly developed for the CB(1) receptor, which is widely expressed on many different neurons, astrocytes and microglia, as well as on many cells outside the CNS. These mouse strains include "floxed" CB(1) alleles and mice with a conditional re-expression of CB(1). The availability of these mice made it possible to decipher the function of CB(1) in specific neuronal circuits and cell populations or to discriminate between central and peripheral effects. Many of the genetic mouse models were also used in combination with viral expression systems. The purpose of this review is to provide a comprehensive overview of the existing genetic models and to summarize some of the most important discoveries that were made with these animals.

Identification of a stable molecular signature in mammary tumor endothelial cells that persists in vitro

Long-term, in vitro propagation of tumor-specific endothelial cells (TEC) allows for functional studies and genome-wide expression profiling of clonally derived, well-characterized subpopulations. Using a genetically engineered mouse model of mammary adenocarcinoma, we have optimized an isolation procedure and defined growth conditions for long-term propagation of mammary TEC. The isolated TEC maintain their endothelial specification and phenotype in culture. Furthermore, gene expression profiling of multiple TEC subpopulations revealed striking, persistent overexpression of several candidate genes including Irx2 and Zfp503 (transcription factors), Alcam and Cd133 (cell surface markers), Ccl4 and neurotensin (Nts) (angiocrine factors), and Gpr182 and Cnr2 (G protein-coupled receptors). Taken together, we have developed an effective method for isolating and culture-expanding mammary TEC, and uncovered several new TEC-selective genes whose overexpression persists even after long-term in vitro culture. These results suggest that the tumor microenvironment may induce changes in vascular endothelium in vivo that are stably transmittable in vitro.

Treatment with CB2 agonist JWH-133 reduces histological features associated with erectile dysfunction in hypercholesterolemic mice

Hypercholesterolemia is one of the most important risk factors for erectile dysfunction, mostly due to the impairment of oxidative stress and endothelial function in the penis. The cannabinoid system might regulate peripheral mechanisms of sexual function; however, its role is still poorly understood. We investigated the effects of CB₂ activation on oxidative stress and fibrosis within the corpus cavernosum of hypercholesterolemic mice. Apolipoprotein-E-knockout mice were fed with a western-type diet for 11 weeks and treated with JWH-133 (selective CB₂ agonist) or vehicle during the last 3 weeks. CB₂ receptor expression, total collagen content, and reactive oxygen species (ROS) production within the penis were assessed. In vitro corpus cavernosum strips preparation was performed to evaluate the nitric oxide (NO) bioavailability. CB₂ protein expression was shown in cavernosal endothelial and smooth muscle cells of wild type and hypercholesterolemic mice. Treatment with JWH-133 reduced ROS production and NADPH-oxidase expression in hypercholesterolemic mice penis. Furthermore, JWH-133 increased endothelial NO synthase expression in the corpus cavernosum and augmented NO bioavailability. The decrease in oxidative stress levels was accompanied with a reduction in corpus cavernosum collagen content. In summary, CB₂ activation decreased histological features, which were associated with erectile dysfunction in hypercholesterolemic mice.

Endogenous cannabinoid receptor CB1 activation promotes vascular smooth-muscle cell proliferation and neointima formation

Percutaneous transluminal angioplasty is frequently used in patients with severe arterial narrowing due to atherosclerosis. However, it induces severe arterial injury and an inflammatory response leading to restenosis. Here, we studied a potential activation of the endocannabinoid system and the effect of FA amide hydrolase (FAAH) deficiency, the major enzyme responsible for endocannabinoid anandamide degradation, in arterial injury. We performed carotid balloon injury in atherosclerosis-prone apoE knockout (apoE(-/-)) and apoE(-/-)FAAH(-/-) mice. Anandamide levels were systemically elevated in apoE(-/-) mice after balloon injury. ApoE(-/-)FAAH(-/-) mice had significantly higher baseline anandamide levels and enhanced neointima formation compared with apoE(-/-) controls. The latter effect was inhibited by treatment with CB1 antagonist AM281. Similarly, apoE(-/-) mice treated with AM281 had reduced neointimal areas, reduced lesional vascular smooth-muscle cell (SMC) content, and proliferating cell counts. The lesional macrophage content was unchanged. In vitro proliferation rates were significantly reduced in CB1(-/-) SMCs or when treating apoE(-/-) or apoE(-/-)FAAH(-/-) SMCs with AM281. Macrophage in vitro adhesion and migration were marginally affected by CB1 deficiency. Reendothelialization was not inhibited by treatment with AM281. In conclusion, endogenous CB1 activation contributes to vascular SMC proliferation and neointima formation in response to arterial injury.

Targeting cannabinoid receptor CB(2) in cardiovascular disorders: promises and controversies

Cardiovascular disease is the leading cause of death and disability worldwide, which can be largely attributed to atherosclerosis, a chronic inflammation of the arteries characterized by lesions containing immune and smooth muscle cells, lipids and extracellular matrix. In recent years, the lipid endocannabinoid system has emerged as a new therapeutic target in variety of disorders associated with inflammation and tissue injury, including those of the cardiovascular system. The discovery that Δ-9-tetrahydrocannabinol (Δ9-THC), the main active constituent of marijuana, inhibited atherosclerotic plaque progression via a cannabinoid 2 (CB(2) ) receptor-dependent anti-inflammatory mechanism, and that certain natural and synthetic cannabinoid ligands could modulate the myocardial or cerebral ischaemia-reperfusion-induced tissue damage, have stimulated impetus for a growing number of studies investigating the implication of CB(2) receptors in atherosclerosis, restenosis, stroke, myocardial infarction and heart failure. The aim of this review is to update on recent findings and controversies on the role of CB(2) receptors in cardiovascular disease. Particular emphasis will be placed on novel insights in the potential cellular targets of CB(2) stimulation in cardiovascular system (e.g. endothelial and vascular smooth muscle cells, cardiomyocytes, infiltrating and/or resident monocytes/macrophages and leukocytes, etc.), their interplay and intracellular signalling mechanisms identified, as well as on experimental and clinical studies.