Probiotics normalize the gut-brain-microbiota axis in immunodeficient mice
Open accessAbstract
The gut-brain-microbiota axis is increasingly recognized as an important regulator of intestinal physiology. Exposure to psychological stress causes activation of the hypothalamic-pituitary-adrenal (HPA) axis and causes altered intestinal barrier function, intestinal dysbiosis, and behavioral changes. The primary aim of this study was to determine whether the effects of psychological stress on intestinal physiology and behavior, including anxiety and memory, are mediated by the adaptive immune system. Furthermore, we wanted to determine whether treatment with probiotics would normalize these effects. Here we demonstrate that B and T cell-deficient Rag1 −/− mice displayed altered baseline behaviors, including memory and anxiety, accompanied by an overactive HPA axis, increased intestinal secretory state, dysbiosis, and decreased hippocampal c-Fos expression. Both local (intestinal physiology and microbiota) and central (behavioral and hippocampal c-Fos) changes were normalized by pretreatment with probiotics, indicating an overall benefit on health conferred by changes in the microbiota, independent of lymphocytes. Taken together, these findings indicate a role for adaptive immune cells in maintaining normal intestinal and brain health in mice and show that probiotics can overcome this immune-mediated deficit in the gut-brain-microbiota axis.
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Lymphocyte deficiency results in impairments in behavior, which can be normalized by probiotic treatment, implicating a specific role of adaptive immunity in the microbiota-gut-brain axis.
“This study, therefore, establishes that lymphocyte deficiency results in impairments in behavior, which can be normalized by probiotic treatment, implicating a specific role of adaptive immunity in the microbiota-gut-brain axis (Smith et al., 2014).”
From The Microbiota-Gut-Brain Axis (2019) · cites this paper as Smith et al., 2014
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- Authors
- Smith, C. J., Emge, J. R., Berzins, K., Lung, L., Khamishon, R., Shah, P., Rodrigues, D. M., Sousa, A. J., Reardon, C., Sherman, P. M., Barrett, K. E., & Gareau, M. G.
- Affiliations
- University of California San Diego (US)
- University of Toronto (CA)
- Corresponding author
- Gareau, Mélanie G.
- ORCID
- Venue
- American Journal of Physiology-Gastrointestinal and Liver Physiology
- Publisher
- American Physiological Society
- Published
- 2014-10-15
- Volume
- 307
- Issue
- 8
- Pages
- G793-G802
- ISSN
- 0193-1857 (ISSN-L)
- 1522-1547
- PMC
- PMC4200314
- OpenAlex
- W2132630422
- Cited by
- 143
- References
- 11
- Citations by year
- 2026: 5 · 2025: 8 · 2024: 11 · 2023: 10 · 2022: 22 · 2021: 10 · 2020: 21 · 2019: 14 · 2018: 14 · 2017: 8 · 2016: 14 · 2015: 5 · 2014: 1
- FWCI
- 3.83
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- American Journal of Physiology-Gastrointestinal and Liver Physiology (publishedVersion)
- Europe PMC (PubMed Central) (publishedVersion)
- PubMed Central (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Crohn's and Colitis Foundation (253542)
- Canadian Institutes of Health Research
- Science and Technology Facilities Council (ST/F012381/1, ST/I504908/1)
- National Cancer Institute (P01CA095616)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Gut microbiota and health
- Life Sciences › Agricultural and Biological Sciences › Food Science › Probiotics and Fermented Foods
- Health Sciences › Medicine › Gastroenterology › Gastrointestinal motility and disorders
- Keywords
- gut-brain-microbiota axis, probiotics, psychological stress, hypothalamic-pituitary-adrenal axis, Rag1-deficient mice, gut dysbiosis, anxiety, memory, intestinal barrier function, adaptive immunity, intestinal physiology
- MeSH terms
- Animals, Anxiety, Female, Hypothalamo-Hypophyseal System, Intestinal Mucosa, Intestines, Lymphocytes, Male, Memory, Mice, Inbred C57BL, Stress, Psychological, Proto-Oncogene Proteins c-fos, Homeodomain Proteins, Probiotics, Mice, Adaptive Immunity, Microbiota
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