cdk5在LPS诱导培养实验大鼠腹主动脉内皮细胞凋亡中的可能作用

目的:探讨周期素依赖性蛋白激酶5(cdk5)在脂多糖(LPS)诱导培养血管内皮细胞(VEC)凋亡中的可能作用。方法:采用原代培养的大鼠腹主动脉EC,经LPS刺激培养不同时间后,ELISA测定cdk5和半氮酶酸蛋白酶-3(caspase-3)活性,同时观察cdk5特异性抑制Roscvitine(Ros)对caspase-3活性的影响;WesternBlot-ting检测cdk5蛋白表达。结果:培养的大鼠腹主动脉EC经LPS(10μg/ml)刺激培养4～24h,其caspase-3活性升高,cdk5活性也明显增强(P<0.05或P<0.01),Ros(25～50μM)可显著抑制LPS刺激培养后VECcaspase-3活性(P<0.05)。培养的EC胞浆及胞核均有cdk5蛋白表达,LPS刺激培养15～30min,cdk5由胞浆向胞核转位,1～8h胞浆及胞核cdk5表达均显著增强(P<0.05或P<0.01)。结论:cdk5可能参与LPS致VEC凋亡。

The Role of cdk5 in Lipopolysaccharide-induced Apoptosis in Vascular Endothelial Cell

Objective: To explore the role of cyclin-dependent protein kinase (cdk5)in lipopolysaccharide (LPS) induced apoptosis in cultured vascular endothelial cell (VEC). Method: The primary cultured abdominal aorta VEC was adoped in current study. The expression of cdk5 in cytosol and nuclear was measured by western blot. The activity of cdk5 and caspase-3 in VEC were detedted by ELISA. Results: The activity of caspase-3 was up-regulated in VEC after treated with LPS (10μg/ml) for 4～24h, especially at 8h. In addition, the activity of cdk5 was enhanced after treated with LPS (10μg/ml) for 4～24h(P<0.05 or P<0.01). The translocation of cdk5 from cytosol to nuclear occurred after treated with LPS (10μg/ml) for 15～30 min, and the expression of cdk5 in cytosol and nuclear were both upregulated after incubated LPS for 1～8h(P<0.05 or P<0.01). Roscvitine (25.0～50.0μM), the specific inhibitor of cdk5, could down-regulate the activation of caspase-3 significantly in VEC stimulated by LPS(10μg/ml) for 4h. Conclusion: cdk5 mightbe closely involved in the occurrence of VEC apoptosis induced by LPS.