Novel non-systemic inhibitor of ileal apical Na+-dependent bile acid transporter reduces serum cholesterol levels in hamsters and monkeys

1-{7-[(1-(3,5-Diethoxyphenyl)-3-{[(3,5-difluorophenyl)(ethyl)amino]carbo nyl}-4-oxo-1,4-dihydroquinolin-7-yl)oxy]heptyl}-1-methylpiperidinium bromide, R-146224, is a potent, specific ileum apical sodium-dependent bile acid transporter (ASBT) inhibitor; concentrations required for 50% inhibition of [3H]taurocholate uptake in human ASBT-expressing HEK-293 cells and hamster ileum tissues were 0.023 and 0.73 μM, respectively. In bile-fistula rats, biliary and urinary excretion 48 h after 10 mg/kg [14C]R-146224, were 1.49 ± 1.75% and 0.14 ± 0.05%, respectively, demonstrating extremely low absorption. In hamsters, R-146224 dose-dependently reduced gallbladder bile [3H]taurocholate uptake (ED50: 2.8 mg/kg). In basal diet-fed hamsters, 14-day 30-100 mg/kg R-146224 dose-dependently reduced serum total cholesterol (∼ 40%), high density lipoprotein (HDL) cholesterol (∼ 37%), non-HDL cholesterols (∼ 20%), and phospholipids (∼ 20%), without affecting serum triglycerides, associated with reduced free and esterified liver cholesterol contents. In normocholesterolemic cynomolgus monkeys, R-146224 specifically reduced non-HDL cholesterol. In human ileum specimens, R-146224 dose-dependently inhibited [3H]taurocholate uptake. Potent non-systemic ASBT inhibitor R-146224 decreases bile acid reabsorption by inhibiting the ileal bile acid active transport system, resulting in hypolipidemic activity. © 2006 Elsevier B.V. All rights reserved. Chemicals / CAS: carbon 14, 14762-75-5; cholesterol, 57-88-5; taurocholic acid, 145-42-6, 59005-70-8, 81-24-3; tritium, 10028-17-8; carrier protein, 80700-39-6; sodium, 7440-23-5; 1-(7-((1-(3,5-diethoxyphenyl)-3-(((3,5-difluorophenyl)(ethyl)amino)carbonyl)-4-oxo-1,4-dihydroquinolin-7-yl)oxy)heptyl)-1-methylpiperidinium bromide; Anticholesteremic Agents; Bile Acids and Salts; Cholesterol, 57-88-5; Membrane Transport Proteins; Organic Anion Transporters, Sodium-Dependent; Piperidines; Quinolines; Sodium, 7440-23-5; sodium-bile acid cotransporter, 145420-23-1; Symporters; Taurocholic Acid, 81-24-3