The Microbiota-Gut-Brain Axis: A New Direction in Research on Depression


  • Emma Chen Phillips Exeter Academy
  • Robert E. Clark University of San Deigo



gut microbiota, gut microbiome, gut-brain axis, microbiota-gut-brain axis, depression, mental health, neuroinflammation, HPA axis, vagus nerve, short-chain fatty acid, neurotransmitter


Depression is a global health crisis that becomes increasingly urgent as depression rates continue to rise. While impressive progress has been made in understanding and treating depression, we face many more unknowns, and existing treatment options are not effective for all patients and all depressive episodes. In recent years, the microbiota-gut-brain axis has emerged as a promising research direction as increasing evidence shows the gut microbiota and the brain to be closely linked. This review presents the most compelling evidence for a bidirectional relationship between the gut microbiota and the brain, zooms in to examine putative neural, neuroimmune, neuroendocrine, and neurometabolic mechanisms involved in bottom-up communication, reviews existing evidence for probiotics, and discusses challenges and future directions of the field. Further research on the microbiota-gut-brain axis could provide a better understanding of the pathogenesis of depression and reveal opportunities for novel preventions and treatments.


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How to Cite

Chen, E., & Clark, R. E. . (2021). The Microbiota-Gut-Brain Axis: A New Direction in Research on Depression. Journal of Student Research, 10(2).



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