Effects of angiotensin Ⅱ on protein kinase Cε and Cα expression in hepatic stellate cells / 中国医师杂志

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.

Effects of Ang-( 1-7 ) on the apoptosis of cultured endothelial cells induced by Ang Ⅱ / 中国医师杂志

Objective To investigate the effect of Ang-(1-7) on the apoptosis in human umbilical vein endothelial cells (HUVECs) induced by Ang Ⅱ.Methods HUVECs were isolated and cultured.Cultured HUVECs were incubated for 24 h with Ang-(1-7), Ang Ⅱ, Ang-(1-7) A-779, Ang-(1-7) + Ang Ⅱ, A-779 + Ang Ⅱ + Ang-( 1-7), respectively.Cultured HUVECs without incubating stimulator were chosen as controls.The apoptosis of endothelial cells were detected by flow cytometry.Results The apoptosis of endothelial cells in HUVECs were upregulated by AngⅡ ( 10-6 mol/L) (25.60% ±3.17% vs 2.32% ±0.24%, P ＜0.005).Compared with the AngⅡ group, Ang-(1-7) dose-dependently inhibited the apoptosis of endothelial cells in HUVECs ( (20.04% ± 2.21% ,16.04% ± 1.32 %, 10.04% ±2.05,7.79% ±1.50% vs AngⅡ group 25.60% ±3.17%, P ＜0.05 , P ＜0.05).The effects of Ang-(1-7) could be blocked by A-779 (23.37% ±0.75% vs 20.04% ± 2.21%, 16.04% ± 1.32,10.04% ± 2.05% ,7.79%± 1.50%, P ＜ 0.05 ).Conclusion Ang-(1-7) can attenuate the apoptosis of endothelial cells induced by Ang Ⅱ in HUVECs in a dose-dependent manner.The effects of Ang-(1-7) could be blocked by A-779( P＜0.05).