Figure 3
PG and PD inhibit IDOL transcription but not LDLR transcription and promoter activity in HepG2 cells. (A, B, E, F) HepG2 cells were treated with 250 μg/mL PG and 1, 2.5 μM PD for 24 h. RT-PCR and Real-time PCR assay were performed to measure the expression of LDLR mRNA (A, B) or IDOL mRNA (E, F). GAPDH was used as a reference gene for quantification analysis. Quantitative real-time PCR represent the mean ± SD from three independent experiments. *P < 0.05 by one-way ANOVA with Tukey’s post hoc test. NS not significant. (C) HepG2 cells were cotransfected with the pRL-TK vector and pLDLR-Luc plasmid. The cells were re-seeded in 12-well plate and treated with PG (250 μg/mL) or PD (1, 2.5 μM) for 24 h. The luciferase activities were measured and normalized with the respective Renilla activity. The data represent the mean ± SD of independent experiments. NS not significant. (D) After treatment of HepG2 cells with 250 μg/mL PG and 1, 2.5 μM PD for 24 h, cell lysates were subjected to western blotting with the indicated antibodies. The figure shows a representative western blot. The intensity of each protein bands from western blotting were determined by Image J software and normalized to that of GAPDH control. Bar graph shows the mean ± SD from three independent experiments.
