SMALL INTESTINE: Edited by Fergus ShanahanA gut (microbiome) feeling about the brainSherwin, Eoin; Rea, Kieran; Dinan, Timothy G.; Cryan, John F. Author Information aAPC Microbiome Institute bDepartment of Psychiatry and Neurobehavioural Science cDepartment of Anatomy and Neuroscience, University College Cork, Cork, Ireland Correspondence to Professor John F. Cryan, Department of Anatomy and Neuroscience, Western Gateway Building, University College Cork, Cork, Ireland. Tel: +353 21 420 5426; e-mail: [email protected] Current Opinion in Gastroenterology: March 2016 - Volume 32 - Issue 2 - p 96-102 doi: 10.1097/MOG.0000000000000244 Buy Metrics Abstract Purpose of review There is an increasing realization that the microorganisms which reside within our gut form part of a complex multidirectional communication network with the brain known as the microbiome-gut-brain axis. In this review, we focus on recent findings which support a role for this axis in modulating neurodevelopment and behavior. Recent findings A growing body of research is uncovering that under homeostatic conditions and in response to internal and external stressors, the bacterial commensals of our gut can signal to the brain through a variety of mechanisms to influence processes such neurotransmission, neurogenesis, microglia activation, and modulate behavior. Moreover, the mechanisms underlying the ability of stress to modulate the microbiota and also for microbiota to change the set point for stress sensitivity are being unraveled. Dysregulation of the gut microbiota composition has been identified in a number of psychiatric disorders, including depression. This has led to the concept of bacteria that have a beneficial effect upon behavior and mood (psychobiotics) being proposed for potential therapeutic interventions. Summary Understanding the mechanisms by which the bacterial commensals of our gut are involved in brain function may lead to the development of novel microbiome-based therapies for these mood and behavioral disorders. Copyright © 2016 Wolters Kluwer Health, Inc. All rights reserved.