Activation of type 2 cannabinoid receptor (CB2R) by selective agonists regulates the deposition and remodelling of the extracellular matrix

In vitro evaluation of cell viability and expression profile of growth factors in mouse Sertoli cells exposed to Delta-9-tetrahydrocannabinol: a mechanistic insight into the cannabinoid-induced testicular toxicity

The potentially adverse effects of cannabis (marijuana), a common leisure compound, on male reproductive performance are a reason for concern. δ-9-tetrahydrocannabinol (THC), the primary active component of marijuana alters testicular cells' proliferation and function which affects male fertility and causes testicular cells dysfunction and apoptosis. The main objective of this study was to investigate the possible mechanism underlying the toxic effects of THC with a mechanistic insight into Sertoli cell-based reproductive dysfunction. The Mus musculus Sertoli cell line (TM4) was cultured and exposed to different concentrations of THC and, MTT (3-(4, 5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was then performed for evaluating cell viability. The expression of caspase-3 gene and genes related to growth factors were analyzed by real-time RT-PCR. Western blotting was performed for evaluating protein expression level. THC concentration-dependently decreased the TM4 viability with a significant effect starting at concentration of 1 μM and reaching about 75% of the control level at the concentration of 50 μM (IC25). Moreover, caspase-3 mRNA expression levels significantly increased while growth factors mRNA levels decreased in THC-exposed cells compared to unexposed cells. There was also a significant reduction in related protein levels in THC group. Administration of the THC promotes cytotoxic and apoptotic effects on TM4 cells partly through down-regulation of growth factors expression. Increased apoptosis, over expression of caspase-3, and down-regulation of growth factors expression in Sertoli cells exposed to THC may be a reflection of THC-induced testicular toxicity, which may be partly involved in infertility associated with marijuana smoking or medical cannabis use.

Mechanisms of weight-loss effect in obese mice by the endogenous cannabinoid receptor 2 agonist beta-caryophyllene

BACKGROUND AND AIMS

The endogenous cannabinoid system (ECS) is involved in the regulation of a variety of physiological activities in the body, such as metabolism and energy uptake, and cannabinoid receptor 2 (CNR2) is one of these receptors that is predominantly distributed in the periphery. β-caryophyllene (BCP) is an agonist of CNR2 which is known to possess pharmacological activities such as anti-inflammatory and antioxidant properties. In this study, we wanted to investigate whether BCP possesses pharmacological effects on obese mice and its mechanism.

METHODS

Reversed feeding rhythm, propylthiouracil was delivered intraperitoneally, and BCP was gavaged once daily for four weeks to establish a hyperlipidemic obese mouse model. A glucose tolerance test, lipid level measurements, liver, peritoneal, and subcutaneous fat removal, HE and Oil Red O staining of the liver, and immunohistochemistry (IHC) staining with an anti-CNR2 antibody were all carried out. The liver was examined using tools like GO and KEGG databases for differentially expressed genes and signaling pathways linked to medication effectiveness.

RESULTS

BCP had significant effects on weight reduction and improvement of dyslipidemia. What's more, it significantly reduced body fat percentage, improved steatosis and ballooning of liver cells, and reduced fat accumulation, while inhibiting the proliferation of peri-abdominal adipocytes. BCP exerted its effects to improve dyslipidemia and reduce body weight probably through circadian regulation and cholesterol metabolic pathways. Finally, and its efficacy in improving dyslipidemia and reducing body weight may be mainly through activating CNR2, activating SIRT1/PGC-1α/PPARγ and SIRT1/AMPK pathways.

CONCLUSION

BCP activates the CNR2, SIRT1/PGC-1α/PPARγ signaling pathway, and SIRT1/AMPK signaling pathway to exert dyslipidemia-improving and weight-loss effects.

In Vitro Antiproliferative Effect of Cannabis Extract PHEC-66 on Melanoma Cell Lines

Melanoma, an aggressive form of skin cancer, can be fatal if not diagnosed and treated early. Melanoma is widely recognized to resist advanced cancer treatments, including immune checkpoint inhibitors, kinase inhibitors, and chemotherapy. Numerous studies have shown that various Cannabis sativa extracts exhibit potential anticancer effects against different types of tumours both in vitro and in vivo. This study is the first to report that PHEC-66, a Cannabis sativa extract, displays antiproliferative effects against MM418-C1, MM329 and MM96L melanoma cells. Although these findings suggest that PHEC-66 has promising potential as a pharmacotherapeutic agent for melanoma treatment, further research is necessary to evaluate its safety, efficacy, and clinical applications.

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.

Activation of cannabinoid receptor 2 alleviates glucocorticoid-induced osteonecrosis of femoral head with osteogenesis and maintenance of blood supply

In glucocorticoid (GC)-induced osteonecrosis of the femoral head (ONFH), downregulated osteogenic ability and damaged blood supply are two key pathogenic mechanisms. Studies suggested that cannabinoid receptor 2 (CB2) is expressed in bone tissue and it plays a positive role in osteogenesis. However, whether CB2 could enhance bone formation and blood supply in GC-induced ONFH remains unknown. In this study, we focused on the effect of CB2 in GC-induced ONFH and possible mechanisms in vitro and in vivo. By using GC-induced ONFH rat model, rat-bone mesenchymal stem cells (BMSCs) and human umbilical vein endothelial cells (HUVECs) to address the interaction of CB2 in vitro and in vivo, we evaluate the osteogenic and angiogenic effect variation and possible mechanisms. Micro-CT, histological staining, angiography, calcein labeling, Alizarin red staining (ARS), alkaline phosphatase (ALP), tartrate-resistant acid phosphatase (TRAP) staining, TUNEL staining, migration assay, scratch assay, and tube formation were applied in this study. Our results showed that selective activation of CB2 alleviates GC-induced ONFH. The activation of CB2 strengthened the osteogenic activity of BMSCs under the influence of GCs by promotion of GSK-3β/β-catenin signaling pathway. Furthermore, CB2 promoted HUVECs migration and tube-forming capacities. Our findings indicated that CB2 may serve as a rational new treatment strategy against GC-induced ONFH by osteogenesis activation and maintenance of blood supply.

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.

The therapeutic potential of cannabinoids for integumentary wound management

The increasing legalization of Cannabis for recreational and medicinal purposes in the United States has spurred renewed interest in the therapeutic potential of cannabinoids (CBs) for human disease. The skin has its own endocannabinoid system (eCS) which is a key regulator of various homeostatic processes, including those necessary for normal physiologic wound healing. Data on the use of CBs for wound healing are scarce. Compelling pre-clinical evidence supporting the therapeutic potential of CBs to improve wound healing by modulating key molecular pathways is herein reviewed. These findings merit further exploration in basic science, translational and clinical studies.

A selective CB2 agonist protects against the inflammatory response and joint destruction in collagen-induced arthritis mice

Rheumatoid arthritis (RA) is a chronic, inflammatory, synovitis-dominated systemic disease with unknown etiology. RA is characterized by the involvement of multiple affected joints, symmetry, and invasive arthritis of the limbs, which can lead to joint deformity, cartilage destruction, and loss of function. Cannabinoid receptor 2 (CB₂) has potent immunomodulatory and anti-inflammatory effects and is predominantly expressed in non-neuronal tissues. In the current study, the role of CB₂ in the process of inflammatory bone erosion in RA was examined. The selective agonist or high-affinity ligand of CB₂ (4-quinolone-3-carboxamides CB2 agonist, 4Q3C CB₂ agonist, 4Q3C) significantly reduced the severity of arthritis, decreased histopathological findings, and markedly reduced bone erosion in collagen-induced arthritis (CIA) mice. In addition, 4Q3C prevented an increase in the nuclear factor-κB ligand (RANKL)/osteoprotegerin (OPG) ratio and inhibited the formation of osteoclasts in CIA mice. Furthermore, the expression of tumor necrosis factor-alpha, interleukin-1β, cyclooxygenase-2, and inducible nitric oxide synthase was lower in 4Q3C-treated CIA mice than in control CIA mice. Micro-computed tomography corroborated the finding that 4Q3C reduced joint destruction. These data clearly indicate that the CB₂-selective agonist, 4Q3C, may have anti-inflammatory and anti-osteoclastogenesis effects in RA and may be considered to be a novel treatment for RA.