Breaking down the gut microbiome composition in multiple sclerosis

Abstract

Background:The gut microbiome, which consists of a highly diverse ecologic community of microorganisms, has increasingly been studied regarding its role in multiple sclerosis (MS) immunopathogenesis. This review critically examines the literature investigating the gut microbiome in MS. Methods: A comprehensive search was performed of PubMed databases and ECTRIMS meeting abstracts for literature relating to the gut microbiome in MS. Controlled studies examining the gut microbiome in patients with MS were included for review. Results: Identified studies were predominantly case-control in their design and consistently found differences in the gut microbiome of MS patients compared to controls. We examine plausible mechanistic links between these differences and MS immunopathogenesis, and discuss the therapeutic implications of these findings. Conclusions: Review of the available literature reveals potential immunopathogenic links between the gut microbiome and MS, identifies avenues for therapeutic advancement, and emphasizes the need for further systematic study in this emerging field.

Multiple Sclerosis and Cancer: The Ying-Yang Effect of Disease Modifying Therapies

“…There are still many questions about how gut bacteria can influence the course of immunity at organs distant from the gut, and whether same bacteria may influence immunity differentially in autoimmune conditions vs. cancer. For example, Bifidobacteria, Akkermansia, and Bacteroides are increased in patients with MS, but may lead to anti-tumor outcomes in cancer patients (195,196). Research to better delineate which bacterial species are most conducive to promoting favorable vs. unfavorable immune outcomes in MS and cancer, will help to pave the road toward more precise risk assessment and manipulation of the gut microbiome in patients with MS and cancer.…”

Are the Gut Bacteria Telling Us to Eat or Not to Eat? Reviewing the Role of Gut Microbiota in the Etiology, Disease Progression and Treatment of Eating Disorders

“…Similarities in the microbial composition and functions among healthy individuals are suggestive of a core microbiome that is required for host health [25]. Many diseases, ranging from metabolic (e.g., obesity and type 2 diabetes) to autoimmune (e.g., multiple sclerosis) and neurodegenerative (e.g., Alzheimer’s disease), have now been linked to dysbiosis [26,27,28] and extensive research efforts have gone into developing treatments to achieve a healthy microbiome. Given that host diet is a key determinant of the gut microbial profile and eating disorders are characterized by dysregulated food intake, it is only logical to assume at least an associative relationship between eating disorders and an altered gut microbiota.…”

“…Psychiatric and neurodevelopmental illnesses, including major depressive disorder [49,50], autism spectrum disorder [51], and multiple sclerosis [26], are consistently associated with a state of dysbiosis. Gut microbes are required for normal brain function.…”

Helicobacter pylori and gut microbiota in multiple sclerosis versus Alzheimer's disease: 10 pitfalls of microbiome studies

“…43 Although the precise pathomechanism is unclear, autoimmunity, genetic background, and environmental factors, such as infections and latitude, appear to contribute to disease onset and exacerbation. 44 Among environmental factors, the gut microbiota has also been proposed to be associated with the pathogenesis of MS. 13,45,46 In high-income countries, lifestyle westernization, including food, water, and sanitation, has decreased several infectious diseases, such as viral hepatitis, and helminth infestations, while chronic inflammatory and autoimmune diseases, including MS and IBD, have been increased. 47 Particularly, “western diet”, rich in fat and salt, has been associated with the increased incidence of MS and IBD.…”

“…45 Case-control studies demonstrated that the microbiome of MS patients differs from that of controls, although it is unknown whether the altered microbiota is a cause or result of development of MS (Table 3). In MS, reproducible changes of microbial taxa are limited, partly because each study often analyzed microbiome at different taxonomic ranks.…”