Multiple Sclerosis: The Disease and its Association with Changes in the Gut Microbiota

The human gut microbiota influences the host’s health through various physiological mechanisms. It interacts with the immune system by modulating the activity of T and B lymphocytes and other immune cells. A balanced microbiota maintains the intestinal barrier function by preserving intestinal mucosa’s integrity and preventing invasions of pathogens. Conversely, an imbalance in gut microbial content, known as dysbiosis, may promote pro-inflammatory immune responses associated with the pathogenesis of various autoimmune neuroinflammatory diseases.Multiple sclerosis (MS) is a chronic autoimmune disease that affects the central nervous system (CNS) and is characterised by demyelination, gliosis, inflammation, and neuronal loss. More than 2.8 million people worldwide have been diagnosed with MS. The incidence of the disease in Lithuania significantly increased between 2001 and 2015. Researchers are investigating the etiology of MS to better understand genetic predisposition and other factors contributing to its development. The gut microbiota is of great interest due to potential links between dysbiosis and the onset of MS. Recent studies indicate that the composition of gut microbiota plays a role in the pathogenesis of MS and is one of the key factors in the development and progression of the disease. The microbiota composition in MS patients differs from that of healthy individuals. A study by Thirion et al. observed a decrease in Peptostreptococcus, Micrococcus, Enterococcus, and Lactobacillus, alongside an increase in bacterial genera such as Staphylococcus, Fusobacterium, Bacteroides, and Porphyromonas in MS patients. Understanding the interaction between the gut microbiota and MS may provide new targets for therapeutic interventions and emphasize the importance of maintaining microbiota balance as a key aspect of neurological health.This review article provides information on the disease, its epidemiology, and etiology, and analyses the association between the microbiota and MS.