Deoxycholic acid

Neutral sterols and bile acids were analyzed as described by Anita Fechner et al. [21 (link)] and Sylvia Keller [22 (link)] using an Agilent GC 7890B-5977B MSD GC-MS system (Agilent Technologies) equipped with a DB-5MS column (0.25 µm, 30 m × 0.25 mm). Total sterols were defined as the sum of cholesterol, coprostanol (Steraloids Inc., Newport, RI, USA), coprostanone (Carbosynth Ltd., Newbury, UK), cholestanol, cholestanone, and cholestenone, and 5α-cholestane was used as the internal standard. All reagents except for coprostanol and coprostanone were purchased from Sigma Aldrich Corporation
Sterol extracts were saponified by the addition of NaOH for bile acid analysis. The primary external standards were cholic acid and chenodeoxycholic acid, and the secondary external standards were iso-lithocholic acid (Steraloids Inc.), lithocholic acid, iso-deoxycholic acid (Steraloids Inc.), and deoxycholic acid; hyodeoxycholic acid was used as the internal standard. All reagents were purchased from Sigma-Aldrich Corporation unless otherwise indicated.

Baicalin (>98%) was purchased from Dalian Meilun Biotechnology Co., Ltd (Meilunbio, Dalian, China). EE was purchased from Sigma-Aldrich Co. (St. Louis, MO, USA). Standards for BAs for cholic acid (CA), deoxycholic acid (DCA), chenodeoxycholic acid (CDCA), β-muricholic acid (β-MCA), taurocholic acid (TCA), taurodeoxycholic acid (TDCA), tauromuricholic acid (T-MCA), taurochenodeoxycholic acid (TCDCA), glycocholic acid (GCA), glycoursodesoxycholic acid (GUDCA), glycohyocholic acid (GHDCA), glycochenodeoxycholic acid (GCDCA), taurohyocholic acid (THDCA), glycodeoxycholic acid (GDCA), and interior label d4-glycochenodeoxycholic acid (d4-GCDCA) were obtained from Steraloids (Newport, RI, USA).
Antibodies directed against FXR, CAR, PXR, VDR, cholesterol 7a-hydroxylase (CYP7A1), and sterol 27-hydroxylase (CYP27A1) were purchased from Absin Biochemical Company (Shanghai, China). Antibodies directed against Sirt1, HNF-1α, tumor necrosis factor α (TNF-α), interleukin 1 beta (IL-1β), IL-6, and NF-κB were purchased from Cell Signaling Technology (Beverly, MA, USA). An antibody against BSEP was obtained from Santa Cruz Biotechnology (CA, USA). And an antibody against MRP2 was obtained from Abcam (Cambridge, UK).