A tryptophan-free diet in mice changes the composition of the intestinal bacteria and protects against symptoms of experimentally generated multiple sclerosis
The research by Dr. Maren Falk-Paulsen and Professor Philip Rosenstiel from the Institute of Clinical Molecular Biology (IKMB) at Kiel University (CAU), in cooperation with a team led by Professor Michael Platten from the DKFZ in Heidelberg, shows that the intestinal microbiome, i.e. the totality of the bacteria in the gut, could also play an important role. They used a mouse model of multiple sclerosis, in which the body's own immune cells attack a specific envelope protein of the nerve insulation in the brain and spinal cord, and thereby cause typical MS symptoms. However, mice that received a special diet in which the amino acid tryptophan was missing, did not develop any MS symptoms in this model. In these mice, the aggressive immune cells did not enter the spinal cord and brain. This protective effect was dependent on the presence of certain bacteria in the gut - if these were missing, then the protection against MS also disappeared.
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