Journal Article

Humid heat environment causes anxiety-like disorder via impairing gut microbiota and bile acid metabolism in mice

Deng, Li, Wu, Jialin, Yu, Lingtai, Zhou, Libing, Chen, Xiaoyin, Wang, Tianyuan, Xu, Huachong, Zhou, Qinji, Weng, Huandi, Chen, Boli, Huang, Li’an, Qu, Yibo

2024

Overview

Climate and environmental changes threaten human mental health, but the impacts of specific environmental conditions on neuropsychiatric disorders remain largely unclear. Here, we show the impact of a humid heat environment on the brain and the gut microbiota using a conditioned housing male mouse model. We demonstrate that a humid heat environment can cause anxiety-like behaviour in male mice. Microbial 16 S rRNA sequencing analysis reveals that a humid heat environment caused gut microbiota dysbiosis (e.g., decreased abundance of Lactobacillus murinus ), and metabolomics reveals an increase in serum levels of secondary bile acids (e.g., lithocholic acid). Moreover, increased neuroinflammation is indicated by the elevated expression of proinflammatory cytokines in the serum and cortex, activated PI3K/AKT/NF-κB signalling and a microglial response in the cortex. Strikingly, transplantation of the microbiota from mice reared in a humid heat environment readily recapitulates these abnormalities in germ-free mice, and these abnormalities are markedly reversed by Lactobacillus murinus administration. Human samples collected during the humid heat season also show a decrease in Lactobacillus murinus abundance and an increase in the serum lithocholic acid concentration. In conclusion, gut microbiota dysbiosis induced by a humid heat environment drives the progression of anxiety disorders by impairing bile acid metabolism and enhancing neuroinflammation, and probiotic administration is a potential therapeutic strategy for these disorders. Humid heat exposure has been shown to alter the gut microbiota and its metabolites. Here, the authors show that transplantation of humid heat-exposed microbiota promotes anxiety-like behaviours, which are ameliorated by Lactobacillus murinus administration.

• Publisher: Nature Publishing Group UK,Nature Publishing Group,Nature Portfolio
• Subject: 1-Phosphatidylinositol 3-kinase / 13/21 / 14/19 / 45/91 / 631/326/2565/2134 / 631/378/1689/1300 / 82/1 / 96/34 / Abnormalities / Abundance / Acids / AKT protein / Animal models / Animals / Anxiety / Anxiety - microbiology / Anxiety disorders / Anxiety Disorders - etiology / Anxiety Disorders - metabolism / Anxiety Disorders - microbiology / Bile acids / Bile Acids and Salts - metabolism / Brain - metabolism / Cytokines - metabolism / Disease Models, Animal / Disorders / Dysbacteriosis / Dysbiosis - microbiology / Environmental changes / Environmental conditions / Gastrointestinal Microbiome / Germfree / Gut microbiota / Heat / Hot Temperature / Humanities and Social Sciences / Humans / Humidity / Inflammation / Intestinal microflora / Lactobacillus / Lithocholic Acid - metabolism / Male / Males / Mental disorders / Metabolism / Metabolites / Metabolomics / Mice / Mice, Inbred C57BL / Microbiota / Microorganisms / multidisciplinary / NF-kappa B - metabolism / NF-κB protein / Probiotics / RNA, Ribosomal, 16S - genetics / rRNA / Science / Science (multidisciplinary) / Sequence analysis / Serum levels / Signal Transduction / Transplantation