Fig. 5.

Effects of NB-598 cotreatments on cyclase inhibitor-mediated induction of PXR-responsive reporter expression in HepG2 cells. HepG2 cells were transiently transfected with pSG5-PXR, XREM-CYP3A4-Luc, and pRL-CMV and then incubated for 24 h with medium alone or containing 0.1% DMSO or 0.1 to 10 μM NB-598, alone or in combination with 10 μMRo 48-8071 (A), 10 μM BIBX 79 (B), 10 μM U18666A (C), or 50 μM rifampicin (D). After treatment, cells were harvested for measurement of firefly and Renilla luciferase activities. Data are expressed as mean normalized (firefly/Renilla) luciferase values ± S.D. (n = 3 wells/treatment group). Groups not sharing a letter are significantly different from each other, p < 0.05.