Gut Bacteria Differs in Multiple Sclerosis Patients

Researchers found for the first time that the patterns of gut microorganisms in people with multiple sclerosis (MS) differ from those of their healthy counterparts, along with differences in which MS patients receive treatment.

For the investigation, researchers used data and samples from individuals who were part of the Comprehensive Longitudinal Investigation of Multiple Sclerosis (CLIMB) study at Brigham and Women’s Hospital. Stool samples from 60 MS patients and 43 control subjects were analyzed using gene sequencing to detect differences in the microbial communities of the subjects.

The results of the study, published in Nature Communications, found that MS samples had higher levels of bacteria, including Methanobrevibacter and Akkermansia, and lower levels of other species, such as Butyricimonas, compared with healthy samples. Prior studies found there are several of these microorganisms that may drive inflammation, or are associated with autoimmunity.

In the current study, the team found that microbial changes in the gut correlated with changes in the activity of genes that play a role in the immune system. Researchers also collected breath samples from the participants, and found that patients with MS had higher levels of methane as a result of increased levels of Methanobrevibacter.

“Our findings raise the possibility that by affecting the gut microbiome, one could come up with treatments for MS — treatments that affect the microbiome, and, in turn, the immune response,” said researcher Howard L. Weiner, MD. “There are a number of ways that the microbiome could play a role in MS and this opens a whole new world of looking at the disease in a way that it’s never been looked at before.”

When researchers examined gut microbe communities of untreated MS patients compared with treated patients, they found that MS disease-modifying therapies appeared to normalize the gut microbiomes of MS patients.

Authors noted that further research is needed to determine the exact role these microbes may play in the progression of MS, and whether or not modifying the microbiome may be beneficial in treating MS. Future research will include a larger group of patients to examine the connection between the immune system and the gut, and following the changes over to time to gain a better understanding of the disease.

“This work provides a window into how the gut can affect the immune system which can then affect the brain,” Weiner said. “Characterizing the gut microbiome in those with MS may provide new opportunities to diagnose MS and point us towards new interventions to help prevent disease development in those who are at risk.”