Synergistic gut microbiome activity may worsen MS symptoms

A new study has found that a combination of certain gut bacteria exacerbates the symptoms of multiple sclerosis (MS) in mice.

Scientists already know that some gut bacteria can affect the symptoms of MS, and it is also implicated as a possible trigger.

In this study, at the RIKEN Center for Integrative Medical Sciences, the mice had demyelination of the spinal cord from autoimmune attacks from T-cells that produce the cytokine IL-17A. Researchers gave the mice ampicillin, an antibiotic, and found it reduced demyelination and prevented the activation of a particular type of T-cell.

The strain of bacteria called OTU002 was almost completely removed in mice treated with ampicillin, and the mice that had this type had more severe symptoms than those that were germ free. But scientists realised the presence of another type of bacteria must have been causing problems, because the mice with only OTU002 were not as bad as the regular mouse model.

They discovered that a bacteria called Lactobacillus reuteri was found to have co-colonized with OTU002 in mice with the worse symptoms.

The researchers say their evidence demonstrates the necessity of considering the synergistic effects of gut microbiome on autoimmune conditions and may lead the way for more effective treatment.