Gut Bacteria MS Link
27 March 2023
A specific toxin-producing gut bacteria may be responsible for triggering the onset of MS and ongoing disease progression, a new study has revealed.
The research identifies epsilon toxin-producing Clostridium perfringens in unusually high amounts in people with MS. It shows that epsilon toxin opens the blood vessels of the brain, allowing inflammatory cells to gain access to the central nervous system and cause demyelination characteristic of MS.
An environmental trigger is required for MS to occur in a genetically susceptible individual, and the abundance of epsilon toxin-producing Clostridium perfringens in people with MS suggests it could be the culprit.
The bacteria lives in the small intestine, and epsilon toxin is only produced briefly when the bacteria is in a growth phase, fitting with the relapsing remitting nature of MS. It specifically targets brain blood vessels and myelin, providing a clear mechanism of its action.
Earlier studies of the gut microbiome in people with MS failed to detect these strains, but the current study used highly sensitive DNA detection techniques to show that people with MS are more likely to carry the bacteria in their small intestines.
Having established this correlation, the investigators tested whether the toxin alone could cause the disease. A previous study, using mice that were predisposed to autoimmunity, showed that MS-like disease only occurred if the mice were also given pertussis toxin. For this new study, epsilon toxin was substituted for pertussis toxin and the mice developed a disease that more closely resembles MS.