Bile acid receptors and transporters

Bile acid receptors and transporters constitute a complex network of proteins responsible for maintaining bile acid homeostasis and regulating metabolic and inflammatory pathways (NIH, 2023). This system includes nuclear receptors like the farnesoid X receptor (FXR) and G protein-coupled receptors such as TGR5, which act as sensors for bile acid levels and trigger signaling cascades affecting lipid, glucose, and energy metabolism (Frontiers in Endocrinology, 2024; NIH, 2023). Transporters like the apical sodium-dependent bile acid transporter (ASBT) and the Na+-taurocholate cotransporting polypeptide (NTCP) facilitate the enterohepatic circulation of bile acids between the liver and intestine (Karger, 2017; NIH, 2021). Dysregulation of these proteins is linked to various conditions, including cholestatic liver diseases, nonalcoholic fatty liver disease (NAFLD), and metabolic disorders (NIH, 2023; ResearchGate, 2024). Pharmacological modulation of these targets, such as FXR agonists for primary biliary cholangitis or ASBT inhibitors for pruritus in cholestasis, has emerged as a significant therapeutic strategy (NIH, 2023; Ovid, 2017). However, challenges such as drug-induced pruritus and alterations in lipid profiles remain important considerations in clinical development (NIH, 2015; Karger, 2017).

Other names

Bile acid signaling systemEnterohepatic circulation proteinsBile acid-activated receptorsBile acid transport system

Pharmacological agents targeting this system function through several distinct mechanisms: farnesoid X receptor (FXR) agonism to downregulate bile acid synthesis and promote efflux; apical sodium-dependent bile acid transporter (ASBT) inhibition to block intestinal reabsorption; Na+-taurocholate cotransporting polypeptide (NTCP) inhibition to prevent hepatic uptake; and TGR5 agonism to modulate metabolic and inflammatory signaling (NIH, 2023; Karger, 2017).