title: Roles of Ileal ASBT and OSTα-OSTβ in Regulating Bile Acid Signaling.
abstract: BACKGROUND
  In addition to their classical role as detergents, bile acids function as signaling molecules to regulate gastrointestinal physiology, carbohydrate and lipid metabolism, and energy expenditure. The pharmacodynamic potential of bile acids is dependent in part on the tight pharmacokinetic control of their concentration and metabolism, properties governed by their hepatic synthesis, enterohepatic cycling, and biotransformation via host and gut microbiota-catalyzed pathways. Key Messages: By altering the normal cycling and compartmentalization of bile acids, changes in hepatobiliary or intestinal transport can affect signaling and lead to the retention of cytotoxic hydrophobic bile acids and cell injury. This review discusses advances in our understanding of the intestinal transporters that maintain the enterohepatic cycling of bile acids, signaling via bile acid-activated nuclear and G protein receptors, and mechanisms of bile acid-induced cell injury.
  
  
  CONCLUSIONS
  Dysregulated expression of the Asbt and Ostα-Ostβ alters bile acid signaling via the gut-liver farnesoid X receptor-fibroblast growth factor 15/19 axis and may contribute to other bile acid-regulated metabolic and cell injury pathways.
authors.affiliation: Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition, Emory University School of Medicine, Atlanta, Ga., USA.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Dawson
mesh_terms: D000818:Animals; D001647:Bile Acids and Salts / Q000378:metabolism*; D019610:Cytoprotection; D004764:Enterohepatic Circulation; D025461:Feedback, Physiological; D006801:Humans; D007082:Ileum / Q000378:metabolism*; D026901:Membrane Transport Proteins / Q000378:metabolism*; D015398:Signal Transduction
chemical_list: D001647:Bile Acids and Salts; D026901:Membrane Transport Proteins