A new study suggests gut bacteria at young age can contribute to multiple sclerosis disease onset and progression. The study’s authors note that future research could lead to the elimination of harmful types of gut bacteria that were shown to cause MS progression, or conversely enhance beneficial bacteria that protects from disease progression.

In this study, researchers at Rutgers Robert Wood Johnson Medical School tested mice that were engineered to have a pre-disposition for MS. Because mice would not normally develop MS, researchers used MS-associated risk genes from real patients to genetically engineer mice for this study.

At first, when the genetically modified mice were put in a sterile, germ-free environment, they did not develop MS. When exposed to a normal environment that would normally contain bacteria, the mice did develop MS-like disease and inflammation in their bowels, suggesting gut bacteria is a risk factor that triggers MS disease development.

The study showed a link between gut bacteria and MS-like disease incidence, which was more prominent at a younger age, when MS is also more prevalent. The younger mice were more prone to develop MS than the older mice. Together, age, gut bacteria, and MS-risk genes collaboratively seem to trigger disease. This study is also the first to identify mechanisms by which gut bacteria triggers changes in the immune system that underlie MS progression.

The findings were published in the Proceedings of the National Academy of Sciences.