Intestinal Flora and Depression: Interaction Mechanisms and Therapeutic Prospects

Abstract

Depression is a mental disorder characterized by high incidence and relapse rates, and the search for effective treatments has been continuously pursued. To assess the effectiveness of existing studies, recent research advances are summarized with an emphasis on potential pathophysiological mechanisms through specific pathways of intestinal flora affecting depression, including microbial and metabolic activities, neuroendocrine regulation, immune and inflammatory responses, and microbial dysbiosis. This review also presents current therapeutic strategies targeting intestinal flora in depression and provides potential directions for future research.

Keywords

Gastrointestinal microbiome - depression - mechanism - therapeutics - gut-brain axis

Publication History

Received: 02 October 2025

Accepted after revision: 02 December 2025

Article published online:
27 February 2026

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