Effect of Z-guggulsterone, CDCA, and both on the expression of mouse bsep, mouse cyp7a1, and esterase activity staining. (A) Expression of mouse bsep and cyp7a1. Mouse primary hepatocytes (n = 3) were treated with Z-guggulsterone (10 μM), CDCA (10 μM), or both for 24 h. DMSO (0.1%) was used as the control. Lysates (25 µg) were resolved by 7.5% SDS-PAGE and transferred electrophoretically to nitrocellulose membranes. The blots were incubated with an antibody against bsep or cyp7a1, developed with chemiluminescent substrate, and reprobed by GAPDH antibody. The signal was captured by Carestream 2200 PRO Imager. (B) Nondenaturing electrophoresis stained for hydrolytic activity. Mouse primary hepatocytes and human HepG2 cells were treated as described above. Lysates from mouse hepatocytes (5 µg) or HepG2 cells (20 µg) were subjected to native gel electrophoresis and stained for esterase activity with 1-naphythalacetate as described in Experimental Procedures. The staining intensity was captured by Carestream 2200 PRO Imager. Note the glycosylation variants of CES.