Abstract
Based on research conducted during the last decade, it is becoming clear that the human microbiota plays an important role in the maintenance of human health. Recently, it has become clear that the human microbiota plays a role not only in physical health but also in mental health, which will be the focus of this chapter. Data suggest that, depending on the diversity and community composition of the human microbiota, the microbiota can either contribute to negative mental health outcomes or promote stress resilience. Here we will focus on the mechanisms through which the human microbiota influences mental health outcomes, with a focus on impacts on brain structure and function. In the context of these mechanisms, we will consider the consequences in humans of the large-scale transition from a hunter-gatherer existence or rural lifestyle to an urban lifestyle and the implications for functioning of the microbiota-gut-brain axis, brain structure and function, and mental health. Finally, we will consider the role of the human microbiota in vulnerability and resilience to stress-related psychiatric disorders, including anxiety disorders, affective disorders, and trauma- and stressor-related disorders, including posttraumatic stress disorder, and the mechanisms involved.
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Acknowledgments
Dr. Christopher A. Lowry is supported by the National Center for Complementary and Integrative Health (grant numbers R01AT010005 and R41AT011390), the Colorado Office of Economic Development and International Trade (OEDIT) Advanced Industries Accelerator Program (grant number CTGG1-2020-3064), and the Department of the Navy, Office of Naval Research Multidisciplinary University Research Initiative (MURI) Award (grant number N00014-15-1-2809).
Compliance with Ethical Standards
The article does not contain any studies with human participants performed by the authors.
Conflict of Interest Statement
C.A.L. serves on the Scientific Advisory Board of Immodulon Therapeutics, Ltd., is cofounder and chief scientific officer of Mycobacteria Therapeutics Corporation, and is a member of the faculty of the Integrative Psychiatry Institute, Boulder, Colorado.
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Sterrett, J.D., Andersen, N.D., Lowry, C.A. (2022). The Influence of the Microbiota on Brain Structure and Function: Implications for Stress-Related Neuropsychiatric Disorders. In: Rook, G.A.W., Lowry, C.A. (eds) Evolution, Biodiversity and a Reassessment of the Hygiene Hypothesis. Progress in Inflammation Research, vol 89. Springer, Cham. https://doi.org/10.1007/978-3-030-91051-8_10
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