Microbiota-gut-brain axis, Part 1: An integrated system of immunological, neural, and hormonal signals

Abstract

A bidirectional signaling exists between the metabolically complex intestinal microbiota, the gut, and the brain.1-3 This highly complex connective system integrates immunological, neural, and hormonal signals between the microbiota-gut-brain axis.4 The intestinal microbiota and its metabolites appear to modulate the peripheral and central nervous systems, influencing brain function and development, whereas the brain affects gastrointestinal (GI) activities, including motility, blood flow, secretions, intestinal permeability, as well as microbiota composition and immunomodulation.