Intestinal Crosstalk between Bile Acids and Microbiota and Its Impact on Host Metabolism

• Published in: Cell metabolism 2016-07, Vol.24 (1), p.41-50
• Main Authors: Wahlström, Annika, Sayin, Sama I., Marschall, Hanns-Ulrich, Bäckhed, Fredrik
• Format: Article
• Language: English
• Subjects: Animals; Bariatric Surgery; Bile Acids and Salts - metabolism; Diet; Gastroenterologi; Gastroenterology and Hepatology; Humans; Intestines - metabolism; Intestines - microbiology; Microbiota; Receptors, Cytoplasmic and Nuclear - metabolism
• ISSN: 1550-4131; 1932-7420; 1932-7420
• DOI: 10.1016/j.cmet.2016.05.005

The gut microbiota is considered a metabolic “organ” that not only facilitates harvesting of nutrients and energy from the ingested food but also produces numerous metabolites that signal through their cognate receptors to regulate host metabolism. One such class of metabolites, bile acids, is produced in the liver from cholesterol and metabolized in the intestine by the gut microbiota. These bioconversions modulate the signaling properties of bile acids via the nuclear farnesoid X receptor and the G protein-coupled membrane receptor 5, which regulate numerous metabolic pathways in the host. Conversely, bile acids can modulate gut microbial composition both directly and indirectly through activation of innate immune genes in the small intestine. Thus, host metabolism can be affected through microbial modifications of bile acids, which lead to altered signaling via bile acid receptors, but also by altered microbiota composition. The gut microbiota can have profound effects on host physiology and metabolism. Many of these effects are mediated by microbial metabolites. Here Wahlström et al. discuss how the microbiota metabolizes bile acids and how it affects signaling through the nuclear receptor FXR in relation to host metabolism.