How Diet Affects Multiple Sclerosis

Intestinal microbiome found to influence MS disease emergence and progression.

The development and progression of autoimmune chronic-inflammatory diseases like multiple sclerosis (MS) could be affected by dietary fatty acids, according to a recent study.

Researchers from the departments of Neurology at the Ruhr-Universitat Bochum and the Friedrich Alexander University Erlangen found that long-chain fatty acids promote the development and propagation of CNS reactive immune cells in the intestinal wall. Meanwhile, short-chain fatty acids promote the development and propagation of regulatory cells in the immune system.

Increasingly, research has been focused on the human intestine and its bacterial population, the microbiome, especially in neurological disorders like MS. In particular with this disease, there is evidence to suggest considerable influence from the intestinal microbiome on disease emergence and progression.

But interaction between intestinal contents and the immune system is influenced by different factors, such as diet, the researchers noted.

The current study demonstrated that in the cell culture dish and in an experimental model, long-chain fatty acids promoted the development and propagation of inflammatory cells in the intestinal wall. Short-chain fatty acids were responsible for the development and propagation of regulatory cells of the immune system in the intestinal wall.

These cells have the capacity to regulate excessive inflammatory responses and autoreactive immune cells.

To the scientists’ surprise, the researchers did not observe any effects from dietary fatty acids once the intestine was free of germs. This means that the intestinal microbiome would have to be directly involved in the mechanism of fatty acid action.

Further research showed that it is the metabolic products of the microbiome rather than a single bacterial strain responsible for the observed effects.

Researchers assume that autoimmune diseases like MS are the result of an imbalance between weakened regulatory and pro-inflammatory autoimmune mechanisms. Currently, the majority of approved immunotherapies works by weakening or blocking pro-inflammatory components of the immune system.

Therapies can be further optimized by strengthening regulatory pathways. The researchers next plan to investigate how to develop innovative dietary add-on therapies to established immunotherapies in MS.