Influence of the Microbiota Through the Gut-Brain Axis in Neurological Diseases

The gut microbiotaMicrobiota strongly interacts with brain, creating the microbiota gut-brain axis. The central nervous system (CNS) is significantly impacted by the gut microbiotaMicrobiota through various pathways, including activation of the vagus nerve, production of metabolites with neuroendocrine functions, and stimulation of immunological responses. Conversely, the brain, in conjunction with the enteric nervous system, exerts control over gastrointestinal tract motility and permeability, intestinal mucus secretion and immune response. Therefore, also the brain has an influence on composition of gut microbiota. Biological communication between the gastrointestinal and CNS is crucial in the pathophysiology and pathogenesis of numerous conditions affecting these systems. As such, the expanding field of microbiota-gut-brain axis research provides a promising framework to further expanding our understanding of disease mechanisms. This chapter aims to synthesize current knowledge in this domain, highlighting recent preclinical and clinical evidence linking the intestinal microbiome and immune system to various neurological disorders. Specifically, we examine involvement of the microbiotaMicrobiota in the onset of several prominent neurological diseases. Additionally, we discuss emerging studies exploring treatments for neurological diseases through manipulation of the gut microbiota such as probioticsProbiotics, prebioticsPrebiotics, synbiotics, and fecal microbiotaMicrobiota transplantation—leveraging interactions along the gut-brain axis.