ABSTRACT
Protein kinase C (PKC) is a special kinase widely distributed in various tissues and cells of human body and involved in signal transduction of hormones and cytokines.It plays an important role in the pathogenesis of many diseases.Therefore,altering the activity of protein kinase C may be an effective treatment for many diseases.This article reviews the progress of protein kinase C in liver diseases.
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 .
ABSTRACT
Objective To investigate the effect of angiotensin Ⅱ on protein kinase Cε (PKCε) and protein kinase Cα (PKCα) expression in hepatic stellate cells.Methods Hepatic stellate cell (HSC)-T6 cells were treated with different concentrations of angiotensin Ⅱ and the proliferation of HSC-T6 cells was detected by methyl thiazolyl tetrazolium (MTT) assay.The expression of PKCε and PKCα was detected by immunofluorescence staining.PKCε and PKCα mRNA levels was detected by real time polymerase chain reaction (PCR).Results Angiotensin Ⅱ concentrated the proliferation of HSC-T6 cells and the level of hydroxyproline (F =25.321,13.283,P ＜ 0.001) and showed a dose-dependent effect.With the increase of angiotensin Ⅱ concentration,PKCε significantly increased and translocated in the cell membrane;PKCα increased significantly,especially in transplanted membrane and cytoplasm (F =21.387,19.431,P ＜0.01),and showed obvious dose effect.Meanwhile,Angiotensin Ⅱ increased the expression of PKCε and PKCα,and induced cell proliferation by up-regulating PKCε and PKCα mRNA levels (F =13.279,15.174,P ＜ 0.05).Conclusions Angiotensin Ⅱ can up-regulate the expression of collagen in hepatic stellate cells in a dose-dependent manner,increase the expression of protein kinase Cε and Cα,and promote the proliferation of hepatic stellate cells.