TY - JOUR T1 - Protective Effects of 6-Ethyl Chenodeoxycholic Acid, a Farnesoid X Receptor Ligand, in Estrogen-Induced Cholestasis JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 604 LP - 612 DO - 10.1124/jpet.104.079665 VL - 313 IS - 2 AU - Stefano Fiorucci AU - Carlo Clerici AU - Elisabetta Antonelli AU - Stefano Orlandi AU - Bryan Goodwin AU - Bahman M. Sadeghpour AU - Giuseppe Sabatino AU - Giuseppe Russo AU - Danilo Castellani AU - Timothy M. Willson AU - Mark Pruzanski AU - Roberto Pellicciari AU - Antonio Morelli Y1 - 2005/05/01 UR - http://jpet.aspetjournals.org/content/313/2/604.abstract N2 - The farnesoid X receptor (FXR), an endogenous sensor for bile acids, regulates a program of genes involved in bile acid biosynthesis, conjugation, and transport. Cholestatic liver diseases are a group of immunologically and genetically mediated disorders in which accumulation of endogenous bile acids plays a role in the disease progression and symptoms. Here, we describe the effect of 6-ethyl chenodeoxycholic acid (6-ECDCA or INT-747), a semisynthetic bile acid derivative and potent FXR ligand, in a model of cholestasis induced by 5-day administration of 17α-ethynylestradiol (E217α) to rats. The exposure of rat hepatocytes to 1 μM 6-ECDCA caused a 3- to 5-fold induction of small heterodimer partner (Shp) and bile salt export pump (bsep) mRNA and 70 to 80% reduction of cholesterol 7α-hydroxylase (cyp7a1), oxysterol 12β-hydroxylase (cyp8b1), and Na+/taurocholate cotransporting peptide (ntcp). In vivo administration of 6-ECDCA protects against cholestasis induced by E217α. Thus, 6-ECDCA reverted bile flow impairment induced by E217α, reduced secretion of cholic acid and deoxycholic acid, but increased muricholic acid and chenodeoxycholic acid secretion. In vivo administration of 6-ECDCA increased liver expression of Shp, bsep, multidrug resistance-associated protein-2, and multidrug resistance protein-2, whereas it reduced cyp7a1 and cyp8b1 and ntcp mRNA. These changes were reproduced by GW4064, a synthetic FXR ligand. In conclusion, by demonstrating that 6-ECDCA protects against E217α cholestasis, our data support the notion that development of potent FXR ligands might represent a new approach for the treatment of cholestatic disorders. The American Society for Pharmacology and Experimental Therapeutics ER -