A new preclinical study, published in Med, a Cell journal, has suggested that the gut plays a key role in developing rheumatoid arthritis.

The study conducted by the researchers of the University College London (UCL), has shown that restoring gut damage could pave the way for a new approach to treating rheumatoid arthritis.

The researchers used mouse models and patient samples to propose that gut restoration could help reduce the severity of rheumatoid arthritis symptoms.

Rheumatoid arthritis is an autoimmune and inflammatory disease, meaning your immune system attacks healthy cells in your body by mistake, causing inflammation in the affected parts of the body, according to the Centers for Disease Control and Prevention (CDC).

The condition mainly attacks the joint(s), especially the joints in the hands, wrists, and knees. Rheumatoid arthritis may also affect other tissues, such as the heart, lungs, and eyes.

The CDC says the specific causes of rheumatoid arthritis are unknown, but there are few factors responsible for increasing the risk of developing the disease.

Recent studies have been exploring how gut bacteria might be involved in the development of rheumatoid arthritis, with experts suggesting that the growth of “bad” bacteria in the gut could initiate the disease.

The study’s co-lead author Prof. Claudia Mauri of UCL said, “We wanted to know what was happening in the gut and whether changes to the intestinal lining—which usually acts as a barrier to protect the body from bacteria—are a feature of the disease and contribute to its development.”

The researchers also found that when the gut becomes “leaky,” it allows the passage of bacteria, causing inflammation both in the gut and potentially in the joints.

Prof. Mauri explained, “Our findings suggest that the intestinal lining is a therapeutic target. Importantly, we found that using existing drugs that restore the gut-barrier integrity i.e., prevent the gut from becoming leaky or inhibit inflammatory cells from moving to and from to the gut, could reduce the severity of arthritis in pre-clinical models.”

“Current treatments for rheumatoid arthritis don’t appear to correct the problems in the gut and so may leave the patient susceptible to reactivation of disease from the continuing inflammation in that area,” she added.

“Going forward, we need to evaluate the therapeutic impact of treating the intestinal lining of rheumatoid arthritis patients in addition to their joints,” Prof Mauri said. “Maintaining gut health both through diet and pharmacological intervention may be a valuable new strategy.”