Role of diet, gut microbiota, and metabolism in multiple sclerosis and neuromyelitis optica

Abstract

AbstractThe prevalence of multiple sclerosis (MS) has been increasing over the past two decades, especially in certain areas, such as the Mediterranean regions and Japan. This increase might be attributed to an altered microbiota and metabolic status in accordance with a change in food habits. Studies on an animal model of MS have led to the hypotheses suggesting the pathogenic role of altered gut microbiota and cellular metabolism of immune cells in MS. Recent studies showed that patients with MS have a distinct gut microbiota composition compared with healthy controls. Furthermore, accumulating evidence highlights the critical role of dysregulated immune cell metabolism in autoimmunity. Regarding neuromyelitis optica (NMO), its microbiome has been reported to have distinct features in comparison with healthy controls and MS. Interestingly, molecular mimicry between aquaporin 4 and components of Clostridium perfringens, the second most significantly enriched taxon in NMO, is suggested. CD4+ T cells recognizing the dominant aquaporin 4 T‐cell epitope show the T helper 17 cell phenotype, and show cross‐reactivity to a homologous peptide sequence in NMO patients. These results raise the possibility that commensal bacteria in NMO patients might be involved in aquaporin 4 autoantibody production. In the present review, we introduce the current advances in the research of food habit and microbiota in MS and NMO in terms of intestinal immunity and immune‐metabolic interactions. In addition, we discuss the potential perspective of diet therapy and probiotics in terms of prophylactic or therapeutic treatment options for MS and NMO.