Changes induced by chronic exposure to high arsenic concentrations in the intestine and its microenvironment. (30th May 2021)

• Record Type: Journal Article
• Authors: Li, Dong; Yang, Yan; Li, Yunxiang; Li, Zeqin; Zhu, Xiaohua; Zeng, Xianyin
• Is Part Of: Toxicology. Volume 456(2021)
• Publication Date: 2021-05-30
• Subjects: Arsenic exposure -- Gene expression -- 16S rRNA microbiome -- UPLC-MS/MS metabolome; Toxicology -- Periodicals; Chemicals -- Physiological effect -- Periodicals; 615.9005
• DOI: 10.1016/j.tox.2021.152767
• Languages: English
• ISSNs: 0300-483X

Abstract

Highlights: As exposure affected the expression of arsenic resistance related genes in intestinal contents. As exposure triggered overall disturbances in the microbiome and metabolome. As exposure induced significant changes in the phenylalanine metabolism. Abstract: The perturbation of intestinal microbes may serve as a mechanism by which arsenic exposure causes or exacerbates diseases in humans. However, the changes in the intestinal microbiome and metabolome induced by long-term exposure to high concentrations of arsenic have not been extensively studied. In this study, C57BL/6 mice were exposed to sodium arsenite (As) (50 ppm) for 6 months. Our results show that long-term exposure to high As concentrations changed the structure of intestinal tissues and the expression of As resistance related genes in intestinal microbes. In addition, 16S rRNA gene sequencing revealed that As exposure significantly affected the Beta diversity of intestinal flora but had no significant effect on the Alpha diversity (except ACE index). Moreover, As exposure altered the composition of the intestinal microbiota from phylum to species. Non-targeted metabolomics profiling revealed that As exposure significantly changed the composition of metabolites, specifically those related to phenylalanine metabolism. Correlation analysis demonstrated that the changes in microbial communities and metabolites were highly correlated under As exposure. Overall, this study demonstrates that long-term exposure to high As concentrations disrupted the intestinal microbiome and metabolome, which may indicate the role of As exposure at inducing human diseases under similar conditions.