Fxr mice

C57BL/6 mice, ob/ob mice, db/db mice, and Fxr^−/− mice were purchased from the Jackson Laboratories (Bar Harbor, Maine, USA). All mice were fed a standard chow diet. Specific FXR agonists GW4064 (31 (link)) (30 mg/kg, twice a day) and OCA (INT-747) (32 (link)) (30 mg/kg/d) have been described previously and were administered by gavage. Unless otherwise stated, male mice were used and all mice were fasted for 5–6 h prior to euthanization. All the animal studies have been approved by the Institutional Animal Care and Use Committee at Northeast Ohio Medical University.

C57BL/6J mice (stock # 000664), Fxr^−/− mice (stock # 004144), Hnf4α^fl/fl mice (stock # 004665) and p53^fl/fl mice (stock # 008462) were purchased from the Jackson Laboratories (Bar Harbor, Maine, USA). Hnf4α^fl/fl mice and Fxr^−/− mice were cross-bred with C57BL/6J mice for at least 10 generations. AAV8-TBG-Null or AAV8-TBG-Cre (produced by Vector Biolabs) was injected to Hnf4α^fl/fl mice or p53^fl/fl mice to generate control mice (Hnf4α^fl/fl mice or p53^fl/fl mice), hepatocyte-specific Hnf4α^−/− (Hnf4α^Hep−/−) mice, or hepatocyte-specific p53^−/− (p53^Hep−/−) mice, respectively. All mice were kept in a temperature- and humidity-controlled room with a 12-h light/12-h dark cycle and free access to water and food. The high fat/cholesterol/fructose (HFCF) diet contained 40% fat/0.2% cholesterol (from TestDiet, AIN-76A), and 4.2% fructose (in drinking water). Mice were fed an HFCF diet for 20 weeks. Unless otherwise stated, male mice were used and were fasted for 5–6 h prior to euthanasia. All the animal experiments were approved by the Institutional Animal Care and Use Committee at Northeast Ohio Medical University (NEOMED).

FVB/NJ, C57BL/6J and FXR (−/−) mice (8-10 weeks) were purchased from Jackson Laboratory (Bar Harbor, ME). SHP (−/−) mice colonies were maintained as previously reported (17 (link)). Mice were maintained under 12-hour light/dark cycles with unlimited access to regular chow and water until the first day of the study. For feeding experiments, male FVB/NJ mice received chow, chow supplemented with 0.3% (w/w) deoxycholic acid (DCA) or chow supplemented with 2% (w/w) cholestyramine for up to 7 days. Male C57BL/6J mice were gavaged with GW4064 (150 mg/kg) as previously described (18 (link)). At the conclusion of each experiment, mice were fasted for 4 hours, the livers were excised, flash-frozen in liquid nitrogen and stored at −70°C. Whole blood was obtained from the right atrium by cardiac puncture. For mice used in bile acid analysis, the liver, gallbladder and small intestine were collected and minced in 100% methanol. Bile duct ligation in female C57BL/6J mice was performed by the Northwestern University Microsurgery Core. All protocols and procedures were approved by the Northwestern University Institutional Animal Care and Use Committee guidelines.

C57BL/6 mice, Fxr^−/− mice, albumin-Cre mice and vilin-Cre were purchased from the Jackson Laboratories (Bar Harbor, Maine, USA). Fxr^fl/fl mice (24 (link)) and Shp^−/− mice (25 (link)) have been described previously. Liver- or intestine-specific Fxr^−/− mice were generated by crossing albumin-Cre mice or vilin-Cre mice with Fxr^fl/fl mice. Where indicated, 10–12 week old mice were gavaged with either vehicle (0.5% carboxymethycellulose, Sigma) or vehicle containing GW4064 (30 mg/kg, twice a day) or OCA (40 mg/kg) for 6–9 days. Adenoviruses expressing rat Cyp7a1 (Ad-rCyp7a1) (26 (link)), mouse Cyp8b1 (Ad-mCyp8b1) (27 (link)), FXRα1-VP16 and FXRα2-VP16 (4 (link)) have been described previously. Unless otherwise stated, the mice were euthanized 7 days post injection. In general, all mice were fasted for 5–6 h prior to euthanization. All the animal experiments were approved by the Institutional Animal Care and Use Committee at Northeast Ohio Medical University.