The Microbiota-Gut-Brain Axis.

Author: Cryan JF1, O'Riordan KJ1, Cowan CSM1, Sandhu KV1, Bastiaanssen TFS1, Boehme M1, Codagnone MG1, Cussotto S1, Fulling C1, Golubeva AV1, Guzzetta KE1, Jaggar M1, Long-Smith CM1, Lyte JM1, Martin JA1, Molinero-Perez A1, Moloney G1, Morelli E1, Morillas E1, O'Connor R1, Cruz-Pereira JS1, Peterson VL1, Rea K1, Ritz NL1, Sherwin E1, Spichak S1, Teichman EM1, van de Wouw M1, Ventura-Silva AP1, Wallace-Fitzsimons SE1, Hyland N1, Clarke G1, Dinan TG1
Affiliation: <sup>1</sup>APC Microbiome Ireland, University College Cork, Cork, Ireland; Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; Department of Psychiatry and Neurobehavioural Science, University College Cork, Cork, Ireland; and Department of Physiology, University College Cork, Cork, Ireland.
Conference/Journal: Physiol Rev.
Date published: 2019 Oct 1
Other: Volume ID: 99 , Issue ID: 4 , Pages: 1877-2013 , Special Notes: doi: 10.1152/physrev.00018.2018. , Word Count: 262


The importance of the gut-brain axis in maintaining homeostasis has long been appreciated. However, the past 15 yr have seen the emergence of the microbiota (the trillions of microorganisms within and on our bodies) as one of the key regulators of gut-brain function and has led to the appreciation of the importance of a distinct microbiota-gut-brain axis. This axis is gaining ever more traction in fields investigating the biological and physiological basis of psychiatric, neurodevelopmental, age-related, and neurodegenerative disorders. The microbiota and the brain communicate with each other via various routes including the immune system, tryptophan metabolism, the vagus nerve and the enteric nervous system, involving microbial metabolites such as short-chain fatty acids, branched chain amino acids, and peptidoglycans. Many factors can influence microbiota composition in early life, including infection, mode of birth delivery, use of antibiotic medications, the nature of nutritional provision, environmental stressors, and host genetics. At the other extreme of life, microbial diversity diminishes with aging. Stress, in particular, can significantly impact the microbiota-gut-brain axis at all stages of life. Much recent work has implicated the gut microbiota in many conditions including autism, anxiety, obesity, schizophrenia, Parkinson's disease, and Alzheimer's disease. Animal models have been paramount in linking the regulation of fundamental neural processes, such as neurogenesis and myelination, to microbiome activation of microglia. Moreover, translational human studies are ongoing and will greatly enhance the field. Future studies will focus on understanding the mechanisms underlying the microbiota-gut-brain axis and attempt to elucidate microbial-based intervention and therapeutic strategies for neuropsychiatric disorders.

KEYWORDS: brain-gut; microbiome; neurogastroenterology; second brain; stress

PMID: 31460832 DOI: 10.1152/physrev.00018.2018