CBG shows potential against rheumatoid arthritis in new study

A new preclinical study conducted by researchers at the Rambam Health Care Campus suggests that the CBG (cannabigerol) could become a promising candidate for the treatment of rheumatoid arthritis (PR). Published in Pharmaceuticals, This study highlights the compound's ability to reduce inflammation by directly modulating the immune cells involved in the pathological process.

Unlike most current treatments for RA, which primarily target inflammatory cytokines after they have been produced, the Israeli team focused on the neutrophils, white blood cells considered to be the main cause of joint inflammation and tissue damage in rheumatoid arthritis.

According to the researchers, there are currently no approved treatments specifically targeting neutrophil activity in RA.

CBG reduced inflammatory markers in human cells

To study the effects of CBG, In the first phase of their research, the scientists isolated neutrophils from human blood samples and exposed them to inflammatory stimuli. They then treated the cells with purified CBG and measured the production of inflammatory cytokines such as TNF-α and the’IL-6, both strongly associated with the severity of rheumatoid arthritis.

The results showed significant reductions in inflammatory signaling. According to the study, CBG reduced TNF-α production by up to 68 % and IL-6 production by up to 72 % in activated human neutrophils. The researchers also observed that CBG inhibited several key inflammatory pathways, including the MAPK, ERK1/2 and Akt.

The study also suggests that part of this anti-inflammatory action may involve the CB2 receptor, a component of the endocannabinoid system mainly associated with immune regulation. Unlike THC, CBG does not bind directly to CB1 receptors in the brain and is therefore considered non-psychoactive.

Reduced immune cell migration and arthritis severity in mice

In addition to cell culture experiments, the researchers also tested CBG on a mouse model of rheumatoid arthritis. Mice treated with this cannabinoid showed lower clinical arthritis scores and less weight loss than untreated animals.

The compound also appeared to reduce the migration of inflammatory immune cells to the affected joints. In particular, CBG significantly inhibited the movement of neutrophils towards the’IL-8, a chemokine known to attract immune cells to inflamed tissue.

Inside the joints of the treated mice, the researchers measured lower levels of inflammatory monocytes and neutrophils, as well as a reduction in cytokines such as’IL-1β, l’IL-6 and the’MCP-1. Blood inflammatory markers were also greatly reduced, with IL-6 levels dropping to 98 % in some experiments.

According to the authors, these results suggest that CBG may help «limit the recruitment of inflammatory immune cells to inflamed joints» and attenuate disease progression in models of RA.

Growing interest in non-psychoactive cannabinoids

Although the CBD and the THC dominated cannabinoid research for a long time, the interest in the CBG has accelerated in recent years. Often referred to as the «mother cannabinoid» because it serves as a precursor to other cannabinoids, CBG has already demonstrated its potential in the treatment of neurological disorders, inflammatory bowel disease and antibacterial applications.

The authors note that CBG remains less studied than CBD or THC, This is partly due to regulatory hurdles and limited clinical data. They also point to several limitations of their work, including the relatively small number of human donors and the short duration of animal experiments.

It is important to note that the study remains in the preclinical stage. Although the results are encouraging, the researchers stress that «further long-term clinical studies are required» before CBG can be considered as a therapeutic option for human patients with rheumatoid arthritis.

The research was partially funded by Raphael Pharmaceutical Inc, which also supplied the purified CBG used in the experiments.