Figure 6.

The inhibition of ERK activity by PD98059 suppresses gene expression of connective tissue growth factor (CTGF) and αI(I) collagen in activated hepatic stellate cell (HSC) in vitro. Serum-starved cells were pretreated with curcumin (Cur) at 20 μM or with PD98059 at indicated concentrations for 30 min prior to the stimulation with fetal bovine serum (FBS) (10%) for additional 24 h. Total RNA or whole-cell extracts were prepared from these cells. (a) Real-time PCR analyses of the steady-state levels of CTGF and αI(I) procollagen (αI(I) col). Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used as an invariant control for calculating mRNA fold changes. Values are expressed as means±s.d. (n=3). ^*P<0.05, versus the untreated control (the corresponding first column on the left). (b) Western blotting analyses of the abundance of CTGF and αI(I) procollagen (αI(I) procol). β-Actin was used as an invariant control for equal loading. Representative blots from three independent experiments are shown.