Hyocholic acid

Chenodeoxycholic acid (1), ursodeoxycholic acid (5), hyodeoxycholic acid (8), hyocholic acid (9), coprostan-3-ol (12), trans-dehydroandrosterone (15), progesterone (17), 11α-hydroprogesterone (18), α-estradiol (19), and diosgenin (22) were purchased from Sigma-Aldrich. Cholic acid (2), lithocholic acid (3), deoxycholic acid (4), cholesterol (11), testosterone (13), and oestron (20) were purchased from Fluka. Dehydrocholic acid (10) and hydrocortisone (21) were purchased from Janssen Chimica and BDH Chemicals, respectively. Glyco (6) and tauroursodeoxycholic acid (7) were prepared as previously reported¹⁴ (link)^,15 (link). Purity of tested compounds 1–22 was >95%.

Bile acids were analyzed using high-performance liquid chromatography coupled to tandem mass spectrometry (HPLC-MS/MS), in the serum from fasted patients and in the liver and plasma from unfasted mice, as previously described,²⁰ (link)^,34 using a Q-Trap 5500. All chemicals and solvents were of the highest purity available. Cholic acid, deoxyCholic acid, chenodeoxyCholic acid, UDCA, lithoCholic acid, hyoCholic acid, hyodeoxyCholic acid and their glyco- and tauro-derivatives were obtained from Sigma-Aldrich (Saint Quentin Fallavier, France); 3-sulfate derivatives were a generous gift from J Goto (Niigita University of Pharmacy and Applied Life Science, Niigata, Japan); 23-Nor-5β-cholanoic acid-3α,12β diol, all muriCholic acids, and their glyco and tauro derivatives were purchased from Steraloids Inc (Newport, USA). Acetic acid, ammonium carbonate, ammonium acetate and methanol, all of HPLC grade, were purchased from Sigma-Aldrich. The hydrophobicity index was determined based on the concentration and retention time of the different bile acids along a methanol gradient on a C18 column, lithoCholic acid and tauroursodeoxyCholic acid-3 S, displaying the highest and lowest retention time, respectively.