Organic Solute Transporter α-β Protects Ileal Enterocytes From Bile Acid-Induced Injury.

Background & Aims: Ileal bile acid absorption is mediated by uptake via the apical sodium-dependent bile acid transporter (ASBT), and export via the basolateral heteromeric organic solute transporter α-β (OSTα-OSTβ). In this study, we investigated the cytotoxic effects of enterocyte bile acid stasis in mice, including the temporal relationship between intestinal injury and initiation of the enterohepatic circulation of bile acids.

Methods: Ileal tissue morphometry, histology, markers of cell proliferation, gene, and protein expression were analyzed in male and female wild-type and mice at postnatal days 5, 10, 15, 20, and 30.

Metabolic effects of intestinal absorption and enterohepatic cycling of bile acids.

The classical functions of bile acids include acting as detergents to facilitate the digestion and absorption of nutrients in the gut. In addition, bile acids also act as signaling molecules to regulate glucose homeostasis, lipid metabolism and energy expenditure. The signaling potential of bile acids in compartments such as the systemic circulation is regulated in part by an efficient enterohepatic circulation that functions to conserve and channel the pool of bile acids within the intestinal and hepatobiliary compartments.