Osteoarthritis

Arthritis is a group of multiple diseases characterised by abnormalities in the musculoskeletal system, most commonly affecting the joints. In Australia, arthritis is the leading cause of chronic pain and disability. There is currently no cure for arthritis although many common medications provide symptomatic relief, as opposed to treating the cause of disease itself. Roughly 95% of cases of arthritis are classed as either osteoarthritis or rheumatoid arthritis.

Osteoarthritis is a characterised by progressive cartilage degradation, leading to inflammation, pain, abnormal bone growth and loss of mobility. Osteoarthritis is commonly associated with a reduction in joint cartilage, and compromised bone integrity. In addition to reducing the painful inflammatory symptoms of osteoarthritis, the endocannabinoid system has also been implicated in the bone remodelling process and has been suggested to prevent abnormal bone growth.

An autoimmune disorder, rheumatoid arthritis occurs when your immune system mistakenly attacks your own body’s tissues. Unlike the wear-and-tear damage of osteoarthritis, rheumatoid arthritis affects the lining of your joints, causing a painful swelling that can eventually result in bone erosion and joint deformity. The inflammation associated with rheumatoid arthritis is what can damage other parts of the body as well.

This image is a simplification for website aesthetics only. For more information please refer to the clinical studies referenced below.

Possible Benefits of Endocannabinoid Activation with Cannabidiol (CBD)

Bone remodelling is the essential process by which bone is mineralised and repaired. Various hormones, peptides and cytokines coordinate this constantly occurring process. The key cells involved in bone remodelling are osteoclasts, osteoblasts and osteocytes. These cells all express CB2 receptors suggesting the endocannabinoid system plays an important modulatory role.

Promotes Homeostasis
The endocannabinoid system has been implicated in maintaining homeostasis in a number of ways. Specifically:

• Cannabinoids influence osteoclast-osteoblast binding
• Osteoblast cultures from CB1 knockout mice express less RANKL (cytokines for osteoclast formation) reducing the potential for bone resorption
• CB2 knockout mice show accelerated age related osteoporosis
• Activation of CB2 receptors increases bone formation markers

Anti-Inflammatory
Activation of the endocannabinoid system has been shown to modulate the inflammation by acting at a number of key junctions within the inflammatory cascade. The endocannabinoid system is postulated to modulate:

• Macrophage and mast cell activation
• Proinflammatory cytokines
• T cell proliferation and apoptosis

Analgesic
The inflammatory reaction inside the joint causes a release of noxious stimuli and inflammatory mediators, leading to pain and loss of mobility. Activation of the endocanabbinoid system has been shown to reduce pain signals in both the peripheral and central nervous system. The specific mechanism of action is thought to be through the excitation of the descending antinociceptive pathway as well as inhibition of painful inflammatory mediators.

Current Treatment

Traditional treatment of arthritis is heavily geared towards the reduction of symptoms such as pain and inflammation. Non-Steroidal Anti-inflammatory Drugs (NSIADs) are most commonly used. NSAIDs have exhibited side effects such as:

• Stomach problems including nausea, ulcers and bleeding
• High blood pressure
• Fluid retention (causing swelling around the lower legs, feet, ankles and hands)
• Kidney problems
• Heart problems
• Rashes

The endocannabinoid system shows great promise in relieving both the underlying cause of osteoarthritis as well as providing symptomatic relief from pain and inflammation without any documented adverse effects in the short or long term.

Pertinent Studies: