51. Bile acid–induced metabolic changes in the colon promote Enterobacteriaceae expansion and associate with dysbiosis in Crohn's disease.
- Author
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Holani, Ravi, Bar-Yoseph, Haggai, Krekhno, Zakhar, Serapio-Palacios, Antonio, Moon, Kyung-Mee, Stacey, Richard G., Donald, Katherine A., Deng, Wanyin, Bressler, Brian, Magaña, Armando A., Foster, Leonard J., Atser, Michael G., Johnson, James D., and Finlay, Brett
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CROHN'S disease ,INFLAMMATORY bowel diseases ,BACTERIAL colonies ,MICROBIAL respiration ,PATHOGENIC bacteria - Abstract
Bile acids (BAs) affect the growth of potentially pathogenic commensals, including those from the Enterobacteriaceae family, which are frequently overrepresented in inflammatory bowel disease (IBD). BAs are normally reabsorbed in the ileum for recycling and are often increased in the colonic lumina of patients with IBD, including those with Crohn's disease (CD). Here, we investigated the influence of BAs on gut colonization by Enterobacteriaceae. We found increased abundance of Enterobacteriaceae in the colonic mucosae of patients with CD with a concomitant decrease in the transporters that resorb BAs in the ileum. The increase in Enterobacteriaceae colonization was greater in the colons of patients who had undergone terminal ileum resection compared with those with intact ileum, leading us to hypothesize that BAs promote intestinal colonization by Enterobacteriaceae. Exposure of human colonic epithelial cell lines to BAs reduced mitochondrial respiration, increased oxygen availability, and enhanced the epithelial adherence of several Enterobacteriaceae members. In a publicly available human dataset, mucosal Enterobacteriaceae was negatively associated with the expression of genes related to mitochondrial function. In a murine model, increased intestinal BA availability enhanced colonization by Escherichia coli in a manner that depended on bacterial respiration. Together, our findings demonstrate that BAs reduce mitochondrial respiration in the colon, leading to an increase in oxygen availability that facilitates Enterobacteriaceae colonization. This identification of BAs as facilitators of host-commensal interactions may be relevant to multiple intestinal diseases. Editor's summary: Crohn's disease is associated with imbalances in the microbiota and increases in bile acids in the colon. Holani et al. investigated whether bile acids were linked to intestinal colonization by Enterobacteriaceae, a family of potentially pathogenic bacteria that are frequently increased in patients with Crohn's disease. Bile acids reduced mitochondrial respiration in human colonic epithelial cells and promoted oxygen-dependent colonization of the mouse intestine by Enterobacteriaceae. Analysis of samples from patients with Crohn's disease showed that Enterobacteriaceae abundance was associated with increases in bile acids and reductions in transcripts related to mitochondrial function. Thus, bile acids promote Enterobacteriaceae colonization of the intestine by increasing oxygen availability. —Annalisa M. VanHook [ABSTRACT FROM AUTHOR]
- Published
- 2024
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