ABSTRACT
Objective To investigate the regulation of interferon α-1b (IFNα-1b) on protein kinase Cε(PKCε) and protein kinase Cα(PKCα) which inhibit the fibrosis of hepatic stellate cells (HSC) ,and to explore its mechanism .Methods HSC-T6 cells were treated with different levels of IFNα-1b (100 , 200 ,400 ,800 and 1000 U/mL) and the proliferation of HSC-T6 cells was analyzed by methyl thiazol tetrazolium (MTT) assay .Changes of hydroxyproline level were analyzed .The expressions of PKCεand PKCαwere detected by immunofluorescence staining . PKCε, PKCα,β-catenin and Survivin mRNA levels were detected by RT-PCR . PKCε, PKCα,β-catenin and Survivin protein levels were detected by Western blot . Variance analysis was conducted by using one-way ANOVA approach . Results The inhibition rates of 100 , 200 , 400 , 800 and 1000 U/mL IFNα-1b treatment after 24 hours of administration were (15 .85 ± 1 .05)％ ,(36 .59 ± 1 .03)％ ,(45 .12 ± 1 .05)％ ,(50 .00 ± 1 .01)％ and (62 .20 ± 1 .02)％ ,respectively ,with statistically significant differences among groups (F=27 .478 , P<0 .01) .The 48h inhibition rates were (20 .87 ± 1 .09)％ ,(43 .96 ± 1 .08)％ ,(53 .85 ± 1 .08)％ ,(64 .84 ± 1 .06)％ and (74 .72 ± 1 .07)％ ,respectively ,with statistically significant differences among groups (F=25 .321 , P< 0 .01 ) . half maximal inhibitory concentration at 48 h was 343 .47 U/mL . The levels of hydroxyproline in 100 ,200 and 400 U/mL IFNα-1b groups were (7 .48 ± 0 .28) ,(6 .26 ± 0 .17) and (3 .86 ± 0 .20) μg/mL ,respectively ,which were lower than that in control group (8 .47 ± 0 .32) μg/mL .The differences were all statistically significant (t=4 .033 ,10 .564 and 21 .160 ,respective ,all P<0 .05) .The fluorescence intensities of PKCεin 100 ,200 and 400 U/mL IFNα-1b groups were all lower than that of control group .The differences were statistically significant (t=1 .984 ,2 .457 and 7 .771 ,respectively ,all P<0 .05) .The fluorescence intensities of PKCαwere also significantly lower than that of control group (t=9 .232 ,15 .921 and 22 .222 ,respectively ,all P< 0 .01) .With the increase of IFNα-1b level ,the levels of HSC-T6 PKCε,PKCα,β-catenin and survivin were significantly lower than those of control group (t=7 .020 ,24 .562 ,45 .701 and 14 .241 ,respectively ,all P<0 .01) .With the increase of IFNα-1b ,the levels of HSC-T6 PKCε,PKCα,β-catenin and survivin were significantly lower than those of control group (t=9 .564 ,4 .409 ,10 .036 and 6 .794 ,respectively ,all P<0 .01) .Conclusions IFNα-1b can down-regulate the expression of collagen in hepatic stellate cells in a dose-dependent manner ,reduce the expressions of PKCε,PKCα,β-catenin and Survivin ,and inhibit the proliferation of HSC-T6 hepatic stellate cells .