Cannabinoid Receptor Type 2 is Upregulated in Synovium following Joint Injury and Mediates Anti-Inflammatory Effects in Synovial Fibroblasts and Macrophages

The effect of protease inhibitors on the indcution of  osteoarthritis-related biomarkers in bovine full-depth cartilage explants -  Osteoarthritis and Cartilage“Objective: Joint injury-induced perturbations to the endocannabinoid system (ECS), a regulator of both inflammation and nociception, remain largely uncharacterized. We employed a mouse model of ACL rupture to assess alterations to nociception, inflammation, and the ECS while using in vitro models to determine whether CB2 agonism can mitigate inflammatory signaling in macrophages and fibroblast-like synoviocytes (FLS).

Conclusions: Joint injury perturbs the intra-articular ECS, characterized by an increase in synovial F4/80(+) cells, which express CB2, but not CB1. Targeting CB2 in murine macrophages and human FLS induced potent anti-inflammatory and anti-catabolic effects, which indicates that the CB2 receptor plays a key role in regulating inflammatory signaling in the two primary effector cells in the synovium. The intraarticular ECS is therefore a potential therapeutic target for blocking pathological inflammation in future disease-modifying PTOA treatments.”

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.”

The Pathophysiology and the Therapeutic Potential of Cannabinoids in Prostate Cancer

cancers-logo“Prostate cancer is the second most frequently occurring cancer diagnosed among males. Recent preclinical evidence implicates cannabinoids as powerful regulators of cell growth and differentiation. In this review, we focused on studies that demonstrated anticancer effects of cannabinoids and their possible mechanisms of action in prostate cancer. Besides the palliative effects of cannabinoids, research from the past two decades has demonstrated their promising potential as antitumor agents in a wide variety of cancers. This analysis may provide pharmacological insights into the selection of specific cannabinoids for the development of antitumor drugs for the treatment of prostate cancer.”

“Prostate cancer, after lung cancer, is the leading cause of death among men. Although the pathophysiological mechanisms and the etiological factors of prostate cancer development are still poorly understood, there are several factors associated with the risk of developing the disease such as age, family history, lifestyle-related factors (e.g., smoking, diet), and testosterone levels. Cannabinoids are an emerging class of pharmacological molecules that may exert their therapeutic effect against different cancers, including those from the prostate. Several studies have shown that various agonists are able to target cannabinoid receptors exhibited on prostate cancer cells.”

Localisation of Cannabinoid and Cannabinoid-Related Receptors in the Horse Ileum

Journal of Equine Veterinary Science“Colic is a common digestive disorder in horses and one of the most urgent problems in equine medicine. A growing body of literature has indicated that the activation of cannabinoid receptors could exert beneficial effects on gastrointestinal inflammation and visceral hypersensitivity.

The localisation of cannabinoid and cannabinoid-related receptors in the intestine of the horse has not yet been investigated. The purpose of this study was to immunohistochemically localise the cellular distribution of canonical and putative cannabinoid receptors in the ileum of healthy horses.

Distal ileum specimens were collected from six horses at the slaughterhouse. The tissues were fixed and processed to obtain cryosections which were used to investigate the immunoreactivity of canonical cannabinoid receptors 1 (CB1R) and 2 (CB2R), and three putative cannabinoid-related receptors: nuclear peroxisome proliferator-activated receptor-alpha (PPARα), transient receptor potential ankyrin 1 and serotonin 5-HT1a receptor (5-HT1aR).

Cannabinoid and cannabinoid-related receptors showed a wide distribution in the ileum of the horse.

The epithelial cells showed immunoreactivity for CB1R, CB2R and 5-HT1aR. Lamina propria inflammatory cells showed immunoreactivity for CB2R and 5-HT1aR. The enteric neurons showed immunoreactivity for CB1R, transient receptor potential ankyrin 1 and PPARα. The enteric glial cells showed immunoreactivity for CB1R and PPARα. The smooth muscle cells of the tunica muscularis and the blood vessels showed immunoreactivity for PPARα.

The present study represents a histological basis which could support additional studies regarding the distribution of cannabinoid receptors during gastrointestinal inflammatory diseases as well as studies assessing the effects of non-psychotic cannabis-derived molecules in horses for the management of intestinal diseases.”

“Horses are often affected by gastrointestinal pathologies. Researchers are searching for new therapies for equine gastrointestinal diseases. New products with cannabinoid receptor agonists have been produced for horses. Cannabinoid receptors showed a wide distribution in the ileum of the horse. Activation of cannabinoids receptors could attenuate intestinal inflammation.”


The Impact of CB1 Receptor on Inflammation in Skeletal Muscle Cells

Dove Medical Press - Open Access Publisher of Medical Journals“Background: Various factors trigger the inflammatory response and cytokine activation in skeletal muscle. Inflamed muscle will exhibit significant levels of inflammation and cytokine activity. Interleukin-6 (IL-6), a pro-inflammatory cytokine, exerts pleiotropic effects on skeletal muscle. Endocannabinoid produced by all cell types binds to a class of G protein-coupled receptors, in particular cannabinoid CB1 receptors, to induce skeletal muscle actions.

Objective: The purpose of this research was to discover whether activation of cannabinoid CB1 receptors in L6 skeletal muscle cells may promote IL-6 gene expression.

Materials and methods: L6 skeletal muscle cells were cultured in 25 cm2 flasks and quantitative reverse transcription-polymerase chain reaction (probe-based) utilised to quantify IL-6 gene expression levels among different treatment settings.

Results: Arachidonyl-2′-chloroethylamide (ACEA) 10 nM, a persistent selective CB1 receptor agonist, promotes IL-6 gene expression in a time-dependent manner. Rimonabant 100 nM, a selective cannabinoid CB1 receptor antagonist, blocks the impact of ACEA. However, insulin does not change IL-6 gene expression.

Conclusion: For the first time, a unique link between ACEA and IL-6 up-regulation has been established; IL-6 up-regulation generated by ACEA is mediated in skeletal muscle through cannabinoid CB1 receptor activation. As a result, cannabinoid CB1 receptors may be useful pharmaceutical targets in the treatment of inflammation and related disorders in skeletal muscle tissues.”

“In the present study, I have demonstrated that when cannabinoid CB1 receptors are activated, the expression of IL-6 increases in a way that is influenced by time. Such findings deliver a novel mechanism characterised by cannabinoid analogue playing the role of a pro-inflammatory mediator in the skeletal muscle tissue. The findings from the present study also imply that there may be a possible therapeutic use of cannabinoid CB1 receptor antagonist at acute early states for skeletal muscle dysfunction related to inflammation. My findings point to skeletal muscle cell cannabinoid CB1 receptor as a therapeutic target, and expand its potential to include anti-inflammatory effects in diabetes, obesity, and sarcopenia.”

Cannabinoid-based therapy as a future for joint degeneration. Focus on the role of CB 2 receptor in the arthritis progression and pain: an updated review

“Over the last several decades, the percentage of patients suffering from different forms of arthritis has increased due to the ageing population and the increasing risk of civilization diseases, e.g. obesity, which contributes to arthritis development. Osteoarthritis and rheumatoid arthritis are estimated to affect 50-60% of people over 65 years old and cause serious health and economic problems. Currently, therapeutic strategies are limited and focus mainly on pain attenuation and maintaining joint functionality. First-line therapies are nonsteroidal anti-inflammatory drugs; in more advanced stages, stronger analgesics, such as opioids, are required, and in the most severe cases, joint arthroplasty is the only option to ensure joint mobility.

Cannabinoids, both endocannabinoids and synthetic cannabinoid receptor (CB) agonists, are novel therapeutic options for the treatment of arthritis-associated pain. CB1 receptors are mainly located in the nervous system; thus, CB1 agonists induce many side effects, which limit their therapeutic efficacy. On the other hand, CB2 receptors are mainly located in the periphery on immune cells, and CB2 modulators exert analgesic and anti-inflammatory effects in vitro and in vivo. In the current review, novel research on the cannabinoid-mediated analgesic effect on arthritis is presented, with particular emphasis on the role of the CB2 receptor in arthritis-related pain and the suppression of inflammation.”

“Cannabinoids not only alleviate joint hyperalgesia but also may help to prevent joint damage, chronic pain development and disease progression.”

β-Caryophyllene, A Natural Dietary CB2 Receptor Selective Cannabinoid can be a Candidate to Target the Trinity of Infection, Immunity, and Inflammation in COVID-19

Frontiers in Pharmacology (@FrontPharmacol) | Twitter“Coronavirus disease (COVID-19), caused by novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing pandemic and presents a public health emergency. It has affected millions of people and continues to affect more, despite tremendous social preventive measures. Identifying candidate drugs for the prevention and treatment of COVID-19 is crucial. The pathogenesis and the complications with advanced infection mainly involve an immune-inflammatory cascade. Therefore, therapeutic strategy relies on suppressing infectivity and inflammation, along with immune modulation.

One of the most promising therapeutic targets for the modulation of immune-inflammatory responses is the endocannabinoid system, particularly the activation of cannabinoid type 2 receptors (CB2R), a G-protein coupled receptor which mediates the anti-inflammatory properties by modulating numerous signaling pathways. To pharmacologically activate the CB2 receptors, a naturally occurring cannabinoid ligand, beta-caryophyllene (BCP), received attention due to its potent anti-inflammatory, antiviral, and immunomodulatory properties. BCP is recognized as a full selective functional agonist on CB2 receptors and produces therapeutic effects by activating CB2 and the nuclear receptors, peroxisome proliferator-activated receptors (PPARs).

BCP is regarded as the first dietary cannabinoid with abundant presence across cannabis and non-cannabis plants, including spices and other edible plants. BCP showed tissue protective properties and favorably modulates numerous signaling pathways and inhibits inflammatory mediators, including cytokines, chemokines, adhesion molecules, prostanoids, and eicosanoids. Based on its pharmacological properties, molecular mechanisms, and the therapeutic potential of BCP as an immunomodulator, anti-inflammatory, organ-protective, and antiviral, we hypothesize that BCP could be a promising therapeutic and/or preventive candidate to target the triad of infection, immunity, and inflammation in COVID-19. In line with numerous studies that proposed the potential of cannabinoids in COVID-19,

BCP may be a novel candidate compound for pharmaceutical and nutraceutical development due to its unique functional receptor selectivity, wide availability and accessibility, dietary bioavailability, nonpsychoactivity, and negligible toxicity along with druggable properties, including favorable pharmacokinetic and physicochemical properties. Based on reasonable pharmacological mechanisms and therapeutic properties, we speculate that BCP has potential to be investigated against COVID-19 and will inspire further preclinical and clinical studies.”

“Over the past few months, it has been suggested that modulation of the endocannabinoid system by cannabinoids, including cannabidiol, could be useful in prophylaxis and treatment of COVID-19 and may improve prognosis. Recently, extract of Cannabis sativa containing phytocannabinoids and terpenes were shown to modulate the inflammatory mediators in alveolar epithelial cells (A549) in COVID-19-associated inflammation and suggested that the phytocannabinoid mix formulation exerted better activity in comparison with individual fractions from cannabis. Many cannabinoids, including cannabidiol, have been suggested for their possible potential as preventive agents or therapeutic adjuvants with other agents in targeting the trinity of infection, inflammation, and immunity in COVID-19.”

“β-caryophyllene (BCP) is a common constitute of the essential oils of numerous spice, food plants and major component in Cannabis.”

“Beta-caryophyllene is a dietary cannabinoid.”

Cannabinoids pharmacological effects are beyond the palliative effects: CB2 cannabinoid receptor agonist induced cytotoxicity and apoptosis in human colorectal cancer cells (HT-29)

SpringerLink“Colorectal cancer (CRC) is between the top three occurring cancers worldwide. The anticancer effects of Cannabinoid receptor 2 (CB2) agonist (GW833972A) in the presence and absence of its inverse agonist (SR144528) on Human colorectal adenocarcinoma cells (HT-29) was investigated. Following cell viability assays on HT-29 and HFF cells, the molecular mechanism(s) of cytotoxicity and apoptotic pathways of cell death were analyzed. The anticancer effects of CB2 agonist were measured with tumor cell migration and colony-forming assays. Real-time PCR and Western blotting techniques were used to examine any alterations in the expression of apoptotic genes. A concentration and time-dependent cytotoxicity of CB2 agonist with IC50 value of 24.92 ± 6.99 μM was obtained. The rate of lipid peroxidation was elevated, while the TNF-α concentration was declined, significantly (p < 0.05). CB2 agonist (50 μM) reduced the colony-forming capability by 83% and tumor cell migration by 50%. Apoptotic effects of CB2 agonist were revealed with the increase of apoptotic cells in Acridine orange/Ethidium bromide staining, clear DNA fragmentation, pro-apoptotic genes and proteins upregulation (Caspase-3 and p53), and significant downregulation of anti-apoptotic Bcl-2. All assessments demonstrated that CB2 agonist-induced effects were reversed by CB2 inverse agonist. These data suggest that CB2 agonists at micro-molar concentrations might be considered in the CRC treatment, and their effectiveness attributes to the apoptosis induction via upregulation of caspase-3 and p53 and downregulation of Bcl-2.”

Cannabinoid receptor activation on hematopoietic cells and enterocytes protects against colitis

Oxford University Press“Cannabinoid receptor (CB) activation can attenuate inflammatory bowel disease (IBD) in experimental models and human cohorts. However, the role of the microbiome, metabolome, or the respective contributions of hematopoietic and non-hematopoietic cells in the anti-colitic effects of cannabinoids has yet to be determined.

Methods: Female C57BL/6 mice were treated with either cannabidiol (CBD), Δ 9-tetrahydrocannabinol (THC), a combination of CBD and THC or vehicle, in several models of chemically induced colitis. Clinical parameters of colitis were assessed by colonoscopy, histology, flow cytometry and detection of serum biomarkers; single-cell RNA sequencing and qRT-PCR were used to evaluate the effects of cannabinoids on enterocytes. Immune cell transfer from CB2 knockout mice was used to evaluate the contribution of hematopoietic and non-hematopoietic cells to colitis protection.

Results: We found that THC prevented colitis, and that CBD, at the dose tested, provided little benefit to the amelioration of colitis, or when added synergistically with THC. THC increased colonic barrier integrity by stimulating mucus, tight junction and antimicrobial peptide production, and these effects were specific to the large intestine. THC increased colonic gram-negative bacteria, but the anti-colitic effects of THC were independent of the microbiome. THC acted on both immune cells via CB2 and on enterocytes to attenuate colitis.

Conclusions: Our findings demonstrate how cannabinoid receptor activation on both immune cells and colonocytes is critical to prevent colonic inflammation. These studies also suggest how cannabinoid receptor activation can be used as a preventive and therapeutic modality against colitis.”

Multi-Target Effects of the Cannabinoid CP55940 on Familial Alzheimer’s Disease PSEN1 E280A Cholinergic-Like Neurons: Role of CB1 Receptor

Get IOS Press NewsAlzheimer’s disease (AD) is characterized by structural damage, death, and functional disruption of cholinergic neurons (ChNs) as a result of intracellular amyloid-β (Aβ) aggregation, extracellular neuritic plaques, and hyperphosphorylation of protein tau (p-Tau) overtime.

Objective: To evaluate the effect of the synthetic cannabinoid CP55940 (CP) on PSEN1 E280A cholinergic-like nerve cells (PSEN1 ChLNs)-a natural model of familial AD.

Results: CP in the presence of both inverse agonists (hereafter SR) almost completely inhibits the aggregation of intracellular sAβPPβf and p-Tau, increases ΔΨm, decreases oxidation of DJ-1Cys106-SH residue, and blocks the activation of c-Jun, p53, PUMA, and caspase-3 independently of CB1Rs signaling in mutant ChLNs. CP also inhibits the generation of reactive oxygen species partially dependent on CB1Rs. Although CP reduced extracellular Aβ 42, it was unable to reverse the Ca2 + influx dysregulation as a response to acetylcholine stimuli in mutant ChLNs. Exposure to anti-Aβ antibody 6E10 (1:300) in the absence or presence of SR plus CP completely recovered transient [Ca2 +]i signal as a response to acetylcholine in mutant ChLNs.

Conclusion: Taken together our findings suggest that the combination of cannabinoids, CB1Rs inverse agonists, and anti-Aβ antibodies might be a promising therapeutic approach for the treatment of familial AD.”

“It is therefore proposed that combinations of cannabinoids, anti-Aβ 42 antibodies (e.g., crenezumab), and CB1 inverse agonists might be a promising multi-target drugs for therapy in the early treatment of FAD PSEN 1 E280A ChLNs neurodegeneration.”