Farnesoid X receptor; G protein-coupled bile acid receptor 1 (FXR; TGR5 (also known as GPBAR1))

Bile acids are cholesterol-derived molecules synthesized in the liver, stored in the gallbladder, and released into the intestine after meals to aid in fat digestion and nutrient absorption[3][4][6]. Beyond their detergent functions, bile acids act as hormones, activating nuclear (FXR) and membrane (TGR5/GPBAR1) receptors in the gastrointestinal tract to regulate bile acid homeostasis, lipid and glucose metabolism, energy expenditure, immune responses, and motility[1][3][4][5]. Abnormal bile acid signaling or transport is linked to diseases including IBD, IBS, diabetes, fatty liver, and gastrointestinal cancers[1][2][3][5]. Drugs targeting FXR and TGR5, as well as bile acid sequestrants and non-toxic bile acids, are used or under investigation for treating cholestatic liver diseases and metabolic disorders[1][2][3][5].

Other names

FXR (Farnesoid X receptor)GPBAR1 (G protein-coupled bile acid receptor 1)TGR5 (Takeda G protein-coupled receptor 5)Bile acid receptorNuclear bile acid receptor (for FXR)G protein-coupled bile acid receptor

FXR agonism (modulates bile acid synthesis, lipid metabolism, anti-inflammatory effects); TGR5 agonism (stimulates GLP-1 secretion, modulates motility and inflammation); Bile acid sequestration (prevents bile acid reabsorption, reduces diarrhea); Replacement with non-cytotoxic bile acids (displaces toxic bile acids)