Decoding the Gut-Brain Axis: A Journey toward Targeted Interventions for Disorders-of-Gut-Brain Interaction

Abstract

Background: The gut-brain axis is a bidirectional communication pathway connecting the gastrointestinal tract and the brain. Disorders of gut-brain interaction (DGBI) manifest as highly prevalent gastrointestinal disorders such as irritable bowel syndrome (IBS) or functional dyspepsia (FD).

Summary: The initial focus of DGBI research was on the effects of psychological stress on digestive functions like gastrointestinal motility, or secretion of gastric acid and pancreatic enzymes. Concepts related to DGBI have expanded in recent decades. Activation of mucosal or systemic immune functions has been observed in DGBI, and it is established that the gastrointestinal microbiome can alter mucosal integrity and permeability, leading to pro-inflammatory cytokine release that affects brain function. Pharmacologic treatments (e.g., tricyclic antidepressants) and non-pharmacologic interventions (e.g., cognitive behavioral therapy) are now standard for DGBI patients. Advances in culture-independent methods to study gastrointestinal microbes reveal new insights into DGBI and gut microbiota appear to play a crucial role in modulating the gut-brain axis and regulating various bodily functions.

Key messages: DGBI are highly prevalent. Research in this field has evolved from studying the effects of psychological stress to recognizing the significant role of the gut microbiome and its metabolites in mucosal integrity and immune responses.

Keywords: Disorders of gut-brain interaction; Functional dyspepsia; Irritable bowel syndrome; Microbiome; Pathophysiology; Psychological stress.