Effect of PKC activity on expression of PDGF and proliferation of hepatic stellate cells

Objective To investigate the effect of protein kinase C (PKC) activity on the expres- sion of platelet derived growth factor (PDGF) and proliferation of hepatic stellate cells (HSCs).Methods rHSC-99 HSCs were randomly divided into 3 groups.Group A served as a control.HSCs were incubated with PKC agonist PMA (0.5μmol/L) as group B or PKC inhibitor Calphestin C (100 nmol/L) as group C.The PKC activity was detected at different incubation time points (0,3,6,12 and 24 h);Western blot- ting was used to detect the expression of PDGF and ERK and immunofluorescence was used to detect the expression ofα-smooth muscle actin (α-SMA) 24 h later.Cell proliferation was assessed by MTT colori- metric assay.Results PMA increased the activity of PKC significantly,whereas Calphostin C inhibited the activity of PKC.The increased activity of PKC promoted HSC to express PDGF,ERK andα-SMA,and as compared with control group,the expression of PDGF,ERK andα-SMA was increased by 1.4,1.2 and 1.3 fold respectively (P0.01,P0.05 and P0.01).The increased activity of PKC also promoted the proliferation of HSCs.These effects could be inhibited by the inhibition of PKC activity.Conclusion Changes in the PKC activity could modulate the expression of PDGF and play a role in regulating the pro- liferation and activation of HSCs.