The Role of Tryptophan Metabolites and Short-Chain Fatty Acids in the Pathogenesis of Autoimmune Diseases

Abstract

Every year, the prevalence of autoimmune diseases in the world is steadily increasing. The etiology and pathogenesis of autoimmune disease are extremely complex and largely remain unclear. However, a growing body of research data in recent years points to the critical role of microorganisms in the formation of normal immune response and autoimmune reactions in the host organism. In this case, one of the leading roles is assigned to the intestinal microbiota, represented by trillions of microbes that form a wide range of signaling and immunoregulatory metabolites. Forming a complex interdependent host-microbiota system, symbiotic bacteria largely determine the development and functioning of human immune cells. In this review, we consider the role of the intestinal microbiota and its key metabolites (namely, short-chain fatty acids and tryptophan metabolites) in the pathogenesis of autoimmune disease and discuss possible mechanisms of the influence of these signaling molecules on host immune cells.