Human ileal bile acid-binding protein (hI-BABP)

Human ileal bile acid-binding protein (hI-BABP) is a cytosolic transporter protein from the intracellular lipid-binding protein (iLBP) family, responsible for binding and shuttling bile acids within epithelial cells of the distal small intestine. hI-BABP plays a key role in the enterohepatic circulation of bile acids, facilitating their intracellular transport and metabolism and thus regulating bile acid homeostasis. It displays a unique binding stoichiometry, with the ability to simultaneously coordinate two bile acid molecules in its internal binding cavity, and its structure undergoes conformational rearrangement upon ligand binding to enable efficient transport. Dysfunction of hI-BABP could contribute to inflammatory bowel disorders and metabolic syndromes connected to altered bile acid profiles. While not a direct target of any approved drugs, it is a potential pharmacological target for modulating bile acid circulation in disease. It facilitates the safe passage of bile acids through the interior of enterocytes, shielding cellular components from their detergent activity and ensuring efficient reuptake into the portal circulation. Loss or dysfunction may exacerbate inflammatory conditions of the gut or interfere with nutrient/drug bioavailability. Targeted modulation could influence systemic bile acid pool and metabolic pathways, potentially offering routes for drug development in gastrointestinal or metabolic diseases.

Other names

I-BABPileal bile acid-binding proteinFABP6Fatty acid binding protein 6

For a hypothetical drug targeting hI-BABP: modulation of bile acid binding and intracellular transport, potentially affecting bile acid pool size and composition in the intestine and liver. For drugs affecting bile acid metabolism (e.g., FXR agonists): indirect alteration of BABP's expression and function by changing bile acid signaling pathways.