Methyl Butyrate Alleviates Experimental Autoimmune Encephalomyelitis and Regulates the Balance of Effector T Cells and Regulatory T Cells

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS), characterized by demyelinating neuropathy. The etiology of MS is not yet clear and its treatment remains a major medical challenge. While we search for drugs that can effectively treat experimental autoimmune encephalomyelitis (EAE), the animal model of MS, we also hope to further explore its possible pathogenesis. In the present study, we investigated whether methyl butyrate (MB) could alleviate EAE and its potential mechanisms. In EAE mice, we found that administration of MB was effective in alleviating their clinical signs and improving histopathological manifestations of the CNS. In the CNS and intestinal lamina propria, we observed fewer effector T cells, including Th1 and Th17, in the MB-treated group. MB also increased the proportion of regulatory T cells and the secretion of IL-10 in peripheral immune organs. In vitro, MB led to suppression of Th1 cells and promotion of regulatory T cells in their differentiation. Given that MB had no direct effect on Th17 cell differentiation in vitro, we hypothesized that MB suppressed Th17 cells indirectly by inhibiting the secretion of IL-6, which was later confirmed both in vitro and in vivo. In addition, we found that MB treatment upregulated Maf gene expression in mice, which explained its promotion of IL-10 secretion. The above findings suggest that MB may provide new ideas for the study of the mechanism of MS and have positive implications for new drug development.