白皮杉醇对过氧化氢诱导的血管平滑肌细胞凋亡的影响与机制

目的:研究白皮杉醇(PCT)对过氧化氢(H2O2)诱导的血管平滑肌细胞(VSMCs)凋亡的影响以及所涉及的相关分子机制。方法:组织贴块法培养SD大鼠VSMCs并进行不同分组与处理;MTT法检测各组VSMCs的存活率;LDH、超氧化物歧化酶(SOD)试剂盒测定各组VSMCs中LDH与SOD活力;Annexin V-PI染色检测各组VSMCs凋亡情况,Hoechst 33258染色观察各组VSMCs细胞核形态变化;Western blot检测各组VSMCs中凋亡相关蛋白(Bcl-2、Bax、caspase-3)及PI3K/AKT/eNOS通路蛋白表达水平。结果:不同浓度与时间过氧化氢(H2O2)处理VSMCs后使其存活率降低,而不同浓度PCT预处理可提高细胞存活率,差异有统计学意义(P<0.05、P<0.01或P<0.001)。与对照组相比,H2O2组VSMCs中LDH活力升高而SOD活力下降,细胞凋亡率增加,细胞中Bax、caspase-3蛋白表达升高而Bcl-2蛋白表达下降,p-PI3K、p-Akt、p-eNOS蛋白表达下降,且均呈剂量依赖关系;与H2O2组相比,PCT预处理组VSMCs LDH活力下降而SOD活力升高,细胞凋亡率降低,细胞中Bax、caspase-3下降,Bcl-2蛋白表达升高,p-PI3K、p-Akt、p-eNOS的蛋白表达升高,且均呈剂量依赖关系,差异有统计学意义(P<0.05或P<0.01)。结论:PCT对H2O2引起的VSMCs损伤有保护作用,其机制可能是抑制LDH活力、增强SOD活力以及增强PI3K/AKT/eNOS信号通路进而阻碍VSMCs凋亡的发生。

Effect and mechanism of paclitaxel on hydrogen peroxide-induced apoptosis of vascular smooth muscle cells

Objective:To study the effects of piceatannol(PCT)on the apoptosis of vascular smooth muscle cells(VSMCs)induced by hydrogen peroxide(H2O2)and the related molecular mechanisms involved.Methods:TSMC patch culture of SD rat VSMCs and different grouping and treatment;MTT method to detect the survival rate of VSMCs in each group;LDH and SOD kits to measure lactate dehydrogenase(LDH),superoxide dismutase(SOD)activity;Annexin V-PI staining was used to detect the apoptosis of VSMCs in each group,Hoechst 33258 staining was used to observe the nuclear morphological changes of VSMCs in each group;Western blot was used to detect apoptosis-related proteins(Bcl-2,Bax,caspase-3)in VSMCs in each group and PI3 K/AKT/eNOS pathway protein expression levels.Results:VSMCs treated with H2O2 at different concentrations and times decreased their survival rate,while pretreatment with different concentrations of PCT could increase cell survival rates,and the differences were statistically significant(P<0.05,P<0.01,or P<0.001).Compared with the control group,the LDH activity in the VSMCs in the H2O2 group increased,while the SOD activity decreased,and the apoptotic rate increased.Bax and caspase-3 protein expression increased while Bcl-2 protein expression decreased.The expressions of p-PI3 K,p-Akt,p-eNOS proteins were decreased,and all showed a dose-dependent relationship.Compared with the H2O2 group,the VSMCs in the PCT pretreatment group had a reduced LDH activity and a higher SOD activity,a decreased apoptosis rate,and decreased Bax and caspase-3,Bcl-2 protein expression increased,p-PI3 K,p-Akt,p-eNOS protein expression increased,and all of them showed a dose-dependent relationship,the difference was statistically significant(P<0.05 or P<0.01).Conclusions:PCT has a protective effect on H2O2 induced VSMCs injury,the mechanism may be inhibition of LDH,enhancement of SOD activity,and enhancement of PI3 K/AKT/eNOS signaling pathway and inhibition of VSMCs apoptosis.