CBG and Osteoarthritis
Current treatments for OA primarily focus on pain management with non-steroidal antiinflammatory drugs (NSAIDs) or steroids with the end point treatment being surgical joint replacement.1-3 Treatments do not target the underlying cause of disease but instead manage symptoms, and they often cause negative side effects. While some potential disease-modifying drugs or treatments that prevent cartilage degeneration are in developmental stages, none are currently available.1,2
In the search for possible targets for disease-modifying treatments for OA, scientists have begun to probe the endocannabinoid system (ECS). Research has shown the presence of both CB1 and CB2 cannabinoid receptors in chondrocytes OA cartilage, synovial tissue, and subchondral bone (bone underneath joint cartilage).2 Knowing these receptors are present in key tissues involved in the disease has led to investigations of the potential effectiveness of endocannabinoids and phytocannabinoids not only in the treatment of the symptoms of OA but also in the restoration and reversal of damage caused to tissues implicated in OA. Here we focus on a lesser-known phytocannabinoid, cannabigerol (CBG), and its therapeutic potential.
In a study conducted by Reyad Elbarbary and Fadia Kamal at Penn State College of Medicine, mouse models were used to investigate the effects of both CBD and CBG on joints affected by OA. It primarily focused on the effects of CBD and CBG on pain, gait, locomotor activity, and joint remodeling. It is important to note that the cannabinoids used in this study came from cannabis extracts that were commercially obtained and contained some terpenes as well as low levels of additional cannabinoids. The CBG oil used in the study contained equal parts CBD and CBG, while the CBD oil used contained primarily CBD, meaning CBG was not studied independently, likely due to its lack of commercial availability.
This study found that treatment with either the CBD or CBG oil significantly reduced the thickness of the synovial membrane, which indicates possible anti-inflammatory effects.1 of Researchers also found that cartilage degeneration was significantly alleviated with the CBG oil treatment but not with the CBD oil treatment.1 This shows CBG as having the potential to stop further joint damage in OA patients. Another important outcome was the discovery that the total number of chondrocytes – the cells that are responsible for building and maintaining the cartilage matrix – was preserved in the mice that were treated with the CBG oil, which supports other findings that CBG demonstrates chondroprotective and potentially chondroregenerative effects.1,4 When examining its effects on ECS receptors, CBG acted as an agonist of the CB2 receptor, which is responsible for preventing the secretion of enzymes that degrade cartilage and also for promoting the production of aggrecan (a major cartilage matrix component).1
Because this study was conducted with extracts as opposed to pure cannabinoids, we must consider the possibility of an entourage effect when examining the therapeutic potential of these cannabinoids. An entourage effect refers to the different cannabinoids and terpenes acting together to produce effects as opposed to just one single compound causing a given effect.4 Nevertheless, this study as well as other research shows the immense potential that phytocannabinoids, specifically CBG, have in the treatment of not only the symptoms of OA but also in the underlying causes of the disease as well.
While more research on the therapeutic potential of cannabinoids, specifically CBG, in the treatment of OA is necessary, foundational studies have provided a framework for Wilkens – 3 future studies and have indicated great promise for CBG. Its possible capacity for painreducing, anti-inflammatory, and disease-modifying effects in the treatment of this common and debilitating disease make it an extremely attractive possible treatment.
- Karuppagounder, V.; Chung, J.; Abdeen, A.; Thompson, A.; Bouboukas, A.; Pinamont, W. J.; Yoshioka, N. K.; Sepulveda, D. E.; Raup-Konsavage, W. M.; Graziane, N. M.; Vrana, K. E.; Elbarbary, R. A.; Kamal, F. Distinctive Therapeutic Effects of Non-Euphorigenic Cannabis Extracts in Osteoarthritis. Cannabis and Cannabinoid Research 2022 (Ahead of Print). (2) Malek, N.; Starowicz, K. Joint Problems Arising from Lack of Repair Mechanisms: Can Cannabinoids Help? British Journal of Pharmacology 2018, 176 (10), 1412–1420. (3) de Lange-Brokaar, B. J. E.; Ioan-Facsinay, A.; van Osch, G. J. V. M.; Zuurmond, A.-M.; Schoones, J.; Toes, R. E. M.; Huizinga, T. W. J.; Kloppenburg, M. Synovial Inflammation, Immune Cells and Their Cytokines in Osteoarthritis: A Review. Osteoarthritis and Cartilage 2012, 20 (12), 1484-1499. (4) Nachnani, R.; Raup-Konsavage, W. M.; Vrana, K. E. The Pharmacological Case for Cannabigerol. The Journal of Pharmacology and Experimental Therapeutics 2021, 376 (2), 204–212.