Molecular Classification
G protein-coupled receptor, Nuclear receptor, Ion channel modulator
Other Names
Bile acid receptors, FXR (Farnesoid X receptor), TGR5 (Takeda G-protein-coupled receptor 5 or GPBAR1), PXR (Pregnane X receptor), VDR (Vitamin D receptor), LXRα/β (Liver X receptor alpha/beta)
Disease Roles
Metabolic diseaseCholestatic liver diseaseInflammatory bowel disease

Bile acid-activated receptors Overview

Bile acids in the intestine are not a single molecular target but a class of endogenous steroid molecules that act as ligands for several distinct cell-surface and nuclear receptors. The most prominent among these are the Farnesoid X Receptor (FXR; NR1H4) and the Takeda G-protein-coupled Receptor 5 (TGR5; also known as GPBAR1). These "bile acid–activated receptors" mediate diverse physiological functions including regulation of bile acid synthesis, transport, glucose/lipid metabolism, immune responses, and inflammation. Bile acids also modulate other nuclear hormone receptors such as Pregnane X Receptor (PXR) and Vitamin D Receptor (VDR). Additionally, they can influence ion channel activity in intestinal tissues. Therapeutically relevant drugs such as obeticholic acid target FXR for treatment of certain liver diseases. However, "bile acids in intestine" is not itself a canonical drug target but refers collectively to this family of ligand-receptors interactions. For structured data purposes, it is more accurate to refer specifically to individual targets like "Farnesoid X receptor" or "G protein-coupled bile acid receptor 1". The entry “Bile acids in intestine” is too broad/vague for use as a canonical therapeutic target name; it should be mapped instead to specific molecular targets such as FXR or TGR5/GPBAR1.

Mechanism of Action

Agonism or antagonism at nuclear or membrane-bound bile acid receptors to regulate gene expression and cellular signaling pathways.

Biological Functions

Regulation of bile acid homeostasis
Signal transduction
Modulation of glucose, lipid, and energy metabolism
Immune response regulation
Inflammatory signaling

Disease Associations

Metabolic disease
Cholestatic liver disease
Inflammatory bowel disease
Cancer

Safety Considerations

  • Off-target effects due to broad tissue distribution of bile acids and their receptors
  • Potential for dysregulation leading to cholestasis or metabolic disturbances

Interacting Drugs

Obeticholic acid (FXR agonist)
Ursodeoxycholic acid (weak GPBAR1 agonist)