https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2828614: Cannabinoids are a group of compounds that mediate their effects through cannabinoid receptors. The discovery of Δ9-tetrahydrocannabinol (THC) as the major psychoactive principle in marijuana, as well as the identification of cannabinoid receptors and their endogenous ligands, has led to a significant growth in research aimed at understanding the physiological functions of cannabinoids. Cannabinoid receptors include CB1, which is predominantly expressed in the brain, and CB2, which is primarily found on the cells of the immune system. The fact that both CB1 and CB2 receptors have been found on immune cells suggests that cannabinoids play an important role in the regulation of the immune system. Recent studies demonstrated that administration of THC into mice triggered marked apoptosis in T cells and dendritic cells, resulting in immunosuppression. In addition, several studies showed that cannabinoids downregulate cytokine and chemokine production and, in some models, upregulate T-regulatory cells (Tregs) as a mechanism to suppress inflammatory responses. The endocannabinoid system is also involved in immunoregulation. For example, administration of endocannabinoids or use of inhibitors of enzymes that break down the endocannabinoids, led to immunosuppression and recovery from immune-mediated injury to organs such as the liver. Manipulation of endocannabinoids and/or use of exogenous cannabinoids in vivo can constitute a potent treatment modality against inflammatory disorders. This review will focus on the potential use of cannabinoids as a new class of anti-inflammatory agents against a number of inflammatory and autoimmune diseases that are primarily triggered by activated T cells or other cellular immune components.
https://www.ncbi.nlm.nih.gov/pubmed/16282192: In the first ever controlled trial of a CBM in RA, a significant analgesic effect was observed and disease activity was significantly suppressed following Sativex treatment. Whilst the differences are small and variable across the population, they represent benefits of clinical relevance and show the need for more detailed investigation in this indication.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2503660: This article reviews recent research on cannabinoid analgesia via the endocannabinoid system and non-receptor mechanisms, as well as randomized clinical trials employing cannabinoids in pain treatment. Tetrahydrocannabinol (THC, Marinol®) and nabilone (Cesamet®) are currently approved in the United States and other countries, but not for pain indications. Other synthetic cannabinoids, such as ajulemic acid, are in development. Crude herbal cannabis remains illegal in most jurisdictions but is also under investigation. Sativex®, a cannabis derived oromucosal spray containing equal proportions of THC (partial CB1 receptor agonist ) and cannabidiol (CBD, a non-euphoriant, anti-inflammatory analgesic with CB1receptor antagonist and endocannabinoid modulating effects) was approved in Canada in 2005 for treatment of central neuropathic pain in multiple sclerosis, and in 2007 for intractable cancer pain. Numerous randomized clinical trials have demonstrated safety and efficacy for Sativex in central and peripheral neuropathic pain, rheumatoid arthritis and cancer pain. An Investigational New Drug application to conduct advanced clinical trials for cancer pain was approved by the US FDA in January 2006. Cannabinoid analgesics have generally been well tolerated in clinical trials with acceptable adverse event profiles. Their adjunctive addition to the pharmacological armamentarium for treatment of pain shows great promise.
https://www.ncbi.nlm.nih.gov/pubmed/24440992: Both mRNA and protein expression of CB2R were found in synovial tissue and cultured FLS with slightly higher levels in RA patients than in OA patients. In cultured RA-FLS, the expression level of CB2R was up-regulated by stimulation with IL-1β, TNF-α or lipopolysaccharide. In vitro, HU-308, a selective CB2R agonist, inhibited IL-1β-induced proliferation of RA-FLS as well as IL-1β-induced production of MMP-3, MMP-13 and IL-6 in RA-FLS in a dose-dependent manner. HU-308 also suppressed IL-1β-induced activation of extracellular signal-regulated kinase 1/2 and p38 mitogen-activated protein kinase in FLS.
In RA-FLS, proinflammatory mediators up-regulate the expression of CB2R, which negatively regulates the production of proinflammatory cytokines and MMPs. These data suggest that CB2R may be a potential therapeutic target of RA.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4851925: These studies demonstrate transdermal administration of CBD has long-lasting therapeutic effects without psychoactive side-effects. Thus, use of topical CBD has potential as effective treatment of arthritic symptomatology. At present, one in five (21%) adults worldwide are diagnosed with some form of arthritis by their physicians (Helmick et al., 2008). The data presented suggest transdermal CBD is a good candidate for developing improved therapies for these debilitating disease.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6222489: The topical anti-inflammatory activity of phytocannabinoids in a roton oil mouse ear dermatitis assay has been described by Tubaro et al. , while preclinical evaluations of the transdermal administration of CBD, via gel application, has been further tested on a rat complete Freund’s adjuvant-induced monoarthritic knee joint model . In this latter study, CBD was found to demonstrate therapeutic potential for the relief of arthritic pain-related behaviour and to exert an anti-inflammation effect without any evident high-brain-center psychoactive effects. Results showed that a dose of 6.2 mg/day reduced knee-joint swelling and that increasing the dose to 62 mg/day failed to yield additional improvements. The transdermal administration of CBD has also been observed to provide better absorption than the oral administration route in same arthritic model .
Cannabis -vs- Rheumatoid Arthritis