Microbial metabolites as a way to provide crosstalk between gut and liver.

Bile acid metabolism is partially regulated through the activity of the gut microbiota. Primary bile acids can be deconjugated and modified by bacteria expressing bile salt hydrolase and other enzymes, changing bile acid recycling by changing the interactions between enterocytes and hepatocytes. The modified bile acids can also activate signalling in cells regulating metabolism including colonic L-cells, skeletal muscle cells and brown adipocytes. In pregnancy, both bile acid metabolism and gut microbiota composition are altered. In women with intrahepatic cholestasis of pregnancy, the changes in bile acid metabolism are exacerbated and there is some evidence that the gut microbiota composition is also altered. Here we review the crosstalk between the liver and the gut especially in women with intrahepatic cholestasis of pregnancy, with a focus on the role of the gut microbiota in this crosstalk.