HSF1对氧化应激诱导内皮细胞凋亡的保护作用的机制研究

Protective Role of Heat Shock Transcription Factor 1 on Apoptosis of Cardiac Microvascular Endothelial Cell During Oxidative Stress

目的探讨热休克转录因子1(HSF1)对过氧化氢(H2O2)刺激后心脏微血管内皮细胞内活性氧簇(ROS)水平和细胞凋亡的影响。方法体外培养大鼠心脏微血管内皮细胞,分别单独转染HSF1质粒、凋亡信号调节激酶1(ASK1)质粒或共转染HSF1及ASK1质粒。转染48h后用1mmol/LH2O2刺激细胞30min,检测并比较各组细胞凋亡情况和胞内ROS水平。结果 (1)H2O2刺激后,各组细胞凋亡较刺激前明显增加(P<0.05);且在相同刺激条件下,HSF1转染组细胞凋亡明显少于对照组(P<0.05),ASK1转染组明显多于对照组(P<0.05),而共转染组与ASK1转染组相比明显减少(P<0.05)。(2)H2O2刺激后,各组细胞内ROS水平较刺激前都显著升高(P<0.05);且在相同刺激条件下,各组细胞内ROS水平较刺激前ROS水平增高的幅度:HSF1转染组明显低于对照组(P<0.05),ASK1转染组和共转染组与对照组无明显差异,而共转染组与HSF1转染组相比有升高趋势,与ASK1转染组相比有降低趋势。结论 HSF1可以通过抑制细胞内ROS产生对抗氧化应激诱导的细胞凋亡,保护心脏微血管内皮细胞。ASK1可能干扰HSF1的保护作用。

Objective To explore the effects of heat shock transcription factor 1（HSF1） on the levels of reactive oxygen species （ROS） and apoptosis in H2O2-induced rat cardiac microvascular endothelial cells. Methods Rat cardiac microvascular endothelial cells were cultured and transfected with the plasmids of HSF1,apoptosis signal-regulating kinase 1（ASK1） or HSF1 with ASK1.Then cells were stimulated with or withou 1 mmol/L H2O2 for 30 minutes. 48 hours later, apoptosis was assessed by TUNEL and ROS levels were measured by flow cytometer. Results （1） Treated with H2O2, apoptosis of every group raised signifi cantly （P0.05）. And in the H2O2-stimulated cells, apoptosis in cells transfection with HSF1 signifi cantly reduced as compared with control（P0.05）, and it signifi cantly increased in ASK1 group when compared with control（P0.05） Meanwhile, apoptosis in the cells transfected with both HSF1 and ASK1 significantly reduced when compared with group transfected with ASK1（P0.05）. （2） Treated with H2O2,ROS levels of every group raised signifi cantly （P0.05）.And in the H2O2-stimulated cells, ROS levels after transfection with HSF1 increased less than group without transfection（P0.05）,while ROS levels in the cells transfected with both HSF1 and ASK1 was slightly increased more than group transfected with HSF1 alone and less than group transfected with ASK1 alone. Conclusion HSF1 can protec cardiac microvascular endothelial cells from oxidative stress through down-regulation of ROS levels and apoptosis in the cells. While ASK1 maybe weaken the protective action.