Role of microbiota-gut-brain axis in autoimmunity and multiple sclerosis

The gut lumen is a complex environment that contains a variety of substances, including food antigens, food-borne pathogens, commensal microorganisms, and their metabolites. The mucosal and intestinal barriers usually prevent these substances from leaking out of the gut. However, dysbiosis, which is a decline in commensal microbes and an increase in pathogenic bacteria, can weaken these barriers and lead to leaky gut syndrome. When the gut barrier is compromised, hostile gut antigens can infiltrate the lamina propria, circulation, and other organs, including the brain. This infiltration can result in immunological inflammation and the emergence of autoimmunity, such as multiple sclerosis (MS). However, research suggests that restoring normal gut microbiota can improve mucosal and intestinal barrier development and immune response modulation, which may aid in preventing autoimmunity and MS. This book chapter discusses the role of gut microbiota in the onset of MS and explores the potential for gut flora normalization as a therapy for this condition. By improving our understanding of the relationship between the gut microbiome and MS, we may be able to develop more effective treatments and preventative measures for this autoimmune disorder.