If you’ve been reading our blog before, you’re probably familiar with cannabinoids and their health effects. In a previous article, we’ve detailed the anti-inflammatory action of these substances, so now it’s time to discuss about the use of CBD and THC in the treatment of arthritis. Can cannabinoids stop arthritis pain?Rheumatoid arthritis (RA) is a systemic inflammatory disease which manifests itself through painful swelling and deterioration of the bones and cartilages. In severe cases, the condition also affects the skin, lungs and even the blood vessels.
The most common symptom of arthritis is joint pain and it is typically treated with anti-inflammatory medications and painkillers. However, given the fact that RA affects mostly senior citizens, medication has to be carefully selected by a physician, in order to avoid cross-reactions with other prescribed drugs that the patients are using. When such risks arise, doctors proceed to recommend alternative treatments for arthritis pain, such as physical exercises, acupuncture and massage therapy, various diets and herbal supplements.
Cannabinoids are pharmacologically active components of the Cannabis sativa plant, which has been used throughout the history in Eastern traditional medicine, predominantly in China and India, for its sedative, analgesic and anti-inflammatory effects.Although Western researchers used to dismiss cannabinoids as a psychoactive recreational plant, recent studies on animal models are demonstrating the anti-arthritic proprieties of the chemical compounds extracted from Cannabis sativa. Interestingly enough, most studies on the effects of cannabinoids in RA patients focus on the non-psychoactive components of the plant.
Cannabidiol (CBD) is one of the 85 active cannabinoids currently known to scientists and it accounts for 40% of the plant’s extract. Its protective effects have been shown to reduce arthritis pain and stiffness in murine collagen-induced arthritis, a controlled type of RA used as a general research tool. Administered on a daily basis, orally or intra-peritoneal, CBD has been shown to inhibit the progression of arthritis.
Tetrahydrocannabinol (THC) is the second most potent cannabinoid compound used in the study of rheumatoid arthritis. While CBD has been found to be efficient for its inhibitory actions in autoimmune models of RA, THC is known for its anti-inflammatory and analgesic proprieties. Given its ability to numb pain and reduce anxiety and depression, THC is currently used in research on a variety of medical conditions, such as cancer, Multiple Sclerosis (MS), Post Traumatic Stress Disorder (PTSD) and Chronic Depression.
RA patients who experience arthritis pain and joint stiffness find THC especially useful, because it helps them soften the side effects of the medication used for the treatment of their condition.
Cannabinoids act via two different receptors – cannabinoid-1 (CB-1), predominantly expressed in the nervous system and cannabinoid-2 (CB-2) receptors, expressed on the immune system. Both CB-1 and CB-2 receptors are involved in the mediation of inflammatory pain characteristic to RA.
In a case study published in PLOS One, CB-2 receptors have been found to regulate the pain response associated with knee joint arthritis. Lab rats were treated with monosodium acetate, in order to induce arthritis-type pain and joint issues.
A close analysis of the subjects revealed an increase in CB2 receptors in neurons and microglia (essential supportive cells for neurons). Injections with JWH133, a cannabinoid compound which stimulates CB-2 receptors, helped reduce the behavior associated with joint. In addition, the mice in the control group presented a decreased amount of CB-2 by comparison with the subjects injected with the JWH133.