Fig 1.
NXT activated PXR to stimulate the CYP2C19 promoter activity.
HepG2 cells were transiently transfected with 2C19-Wt, 2C19-Mut and pcDNA3.1-PXR or pcDNA3.1 for 24 hours and then treated by 0.1% DMSO, 10μM rifampicin, 150 and 250μg/mL NXT for 24 hours, respectively. (A) Luciferase activity of HepG2 cells transiently transfected with 2C19-Wt and pcDNA3.1-PXR or pcDNA3.1 with treatment, was measured; (B) Luciferase activity of HepG2 cells transiently transfected with 2C19-Wt, 2C19-Mut and pcDNA3.1-PXR with treatment, was measured. Rif: rifampicin; NXT-150 and -250: 150 and 250μg/mL NXT; Vehicle: pcDNA3.1 vector; PXR: pcDNA.1-PXR expression plasmid. Data was presented as the mean±S.D from three independent experiments. ***P<0.001 vs. DMSO group.
Fig 2.
NXT inductive effects on the CYP2C19 mRNA expression in HepG2 cells.
HepG2 cells were transiently transfected with pcDNA3.1-PXR or pcDNA3.1 for 24 hours and then incubated with 0.1% DMSO, 10μM rifampicin, 150 and 250μg/mL NXT for 24 hours, respectively. Rif: rifampicin; NXT-150 and -250: 150 and 250μg/mL NXT; Vehicle: pcDNA3.1 vector; PXR: pcDNA3.1-PXR expression plasmid. Data was presented as the mean±S.D from three independent experiments. ***P<0.001 vs. DMSO group.
Fig 3.
NXT induced the CYP2C19 protein expression in HepG2-PXR cells.
HepG2 cells were transiently transfected with pcDNA3.1-PXR for 24 hours and then incubated with 0.1% DMSO, 10μM rifampicin, 150 and 250μg/mL NXT for 24 hours, respectively. (A) the transfection efficiency of pcDNA3.1-PXR in HepG2 cells; (B) expression of CYP2C19 protein analyzed by Western blotting; (C) accurate induction of NXT on CYP2C19 protein were quantified by densitometry. Rif: rifampicin; NXT-150 and -250: 150 and 250μg/mL NXT; Data was presented as the mean±S.D from three independent experiments. *P<0.05,**P<0.01 vs. DMSO group.
Fig 4.
NXT elevated the CYP2C19 metabolic activity in HepG2-PXR cells.
HepG2 cells were transiently transfected with pcDNA3.1-PXR for 24 hours and then incubated with 0.1% DMSO, 10μM rifampicin, 150 and 250μg/mL NXT for 24 hours respectively. Luciferin produced by CYP2C19 was detected by a luminometer and finally normalized by protein concentration. Rif: rifampicin; NXT-150 and -250: 150 and 250μg/mL NXT; Data was presented as the mean±S.D from three independent experiments. *P<0.05, **P<0.01, ***P<0.001 vs. DMSO group.