Scientists have identified two species of gut bacteria that may contribute to triggering the immune response implicated in multiple sclerosis (MS), a chronic neurological disease affecting millions worldwide. The findings, stemming from research at Germany's Max Planck Institute, suggest a potential link between the gut microbiome and the development of MS, offering new avenues for prediction and treatment.
MS affects the central nervous system, causing damage to the myelin sheath that protects nerve fibers. This damage can lead to a range of symptoms, including fatigue, vision problems, mobility issues, and cognitive disturbances. The disease is on the rise globally, with cases in the UK doubling between 2000 and 2020, and a concerning increase in diagnoses among younger individuals.
The research, published in the Proceedings of the National Academy of Sciences, examined twins where one had MS and the other did not. By analyzing gut bacteria in stool and small intestine samples, scientists identified two bacteria, Eisenbergiella tayi and Lachnoclostridium, present only in the twins with MS. When these bacteria were introduced to mice, the animals developed MS-like symptoms, strengthening the hypothesis of their involvement.
Researchers caution that these bacteria are not the sole cause of MS, which is understood to result from a complex interaction of genetic, immune, and environmental factors. Other known risk factors include obesity, smoking, vitamin D deficiency, and infection with the Epstein-Barr virus. However, the identification of these specific gut microbes provides a significant new piece in understanding the disease's complex puzzle.
Professor Ruth Dobson, of Queen Mary University of London's Centre for Preventive Neurology, explained that the immune system, highly active in the gut, may mistakenly attack myelin in the brain because some bacterial components resemble brain cells. "Essentially the immune system thinks its attacking the bugs but is actually attacking the myeline on the nerve fibres," she stated.
While it is too early to recommend specific probiotics, dietary changes that promote gut health are advised. Experts recommend avoiding ultra-processed foods, which are high in refined sugars and chemical additives, and opting for a varied diet rich in fiber, fresh fruits, and vegetables. Maintaining a healthy weight, particularly during adolescence, is also noted as crucial, as adolescent obesity has been linked to a doubled risk of developing MS later in life.
These findings have generated significant interest and optimism, potentially paving the way for future screening methods to identify individuals at increased risk and, eventually, targeted therapies to prevent or treat the disease. Understanding the mechanisms behind MS is considered vital for patients seeking explanations and for advancing strategies to combat this incurable condition. For instance, Becky Lee, diagnosed with MS at 32 after experiencing subtle symptoms since age 21, highlights the importance of recognizing early signs and the ongoing journey to understand the disease's origins.
The UK has one of the highest rates of MS globally, with approximately 7,000 new cases diagnosed annually. Women are about two and a half times more likely to be affected than men.