Abstract: Bile acids are the main products of the cholesterol degradation in the liver. They promote the absorption and transportation of the intestinal lipids. Diverse bile acid receptors are widely distributed in human tissues and organs, including farnesoid X receptor (FXR) and Takeda G protein receptor (TGR5). The expression pattern of different bile acid receptors and their different affinities to various bile acids as their ligands determines their pleiotropic downstream effects, including regulating bile acid synthesis and transportation, immune and metabolism homeostasis. In addition, the bile acid pool includes components derived from both host and gut microbiota, which collaboratively contribute to the bile acid signaling activation in different compartments. Therefore, bile acid pool represents an information hub allowing the crosstalk between the host and gut microbiome and hereby modulating host metabolic homeostasis and gut microbiome symbiosis. This article reviews the recent advances in the field of bile acid regulation and the related mechanisms of bile acid signaling pathway to maintain metabolic homeostasis.

Key words: bile acid, bile acid receptor, glucose metabolism, inflammation