过表达HSF1及ASK1基因对H_2O_2刺激后心肌细胞内ROS水平的影响

The influences of overexpression of HSF1 and ASK1 on ROS levels in H_2O_2-treated cardiac myocytes

目的研究热休克因子1(HSF1)及凋亡信号调节激酶1(ASK1)对过氧化氢(H_2O_2)刺激后心肌细胞内活性氧簇水平(ROS)变化的影响。方法对不同组培养心肌细胞分别单独转染质粒HSF1,ASK1,及共转染HSF1+ASK1,48h待其充分表达后用1 mmol/LH_2O_2刺激心肌细胞30min,检测细胞内ROS水平,并与相应转染后未刺激组及未转染的对照组比较,观察ROS水平的变化。结果(1)所有H_2O_2刺激组心肌细胞内ROS水平均高于相同转染条件下的非刺激组(P<0.05);(2)相同H_2O_2刺激条件下,各组ROS水平:HSF1组低于对照组(P<0.05),ASK1组与对照组无显著差异,HSF1+ASK1组与单转HSF1组相比有升高的趋势;(3)相同H_2O_2刺激条件下,各组刺激后比刺激前ROS水平增高的幅度:HSF1组低于对照组(P<0.05),ASK1组与对照组无显著差别,HSF1+ ASK1组与单转HSF1组相比有升高的趋势。结论在H_2O_2刺激条件下,HSF1可通过降低心肌细胞内的ROS水平来发挥细胞保护作用,而ASK1对细胞内ROS水平无影响,但其可干扰HSF1对ROS的抑制作用。

Objective To observe the influences of heat shock factor 1 （ HSF1 ） and apoptosis signal-regulating kinase 1 （ASK1） on the levels of reactive oxygen species （ROS） in cultured cardiac myocytes treated with oxidative stress. Methods After transfection of plasmids of HSF1, ASK1 or HSF1 with ASK1 into cardiac myocytes, the cells were stimulated with or without H2O2 （1mmol/L）for 30 minutes. 48 hours later,the levels of ROS in the cells were detected. Results （ 1 ） the levels of ROS in the cells stimulated with H2O2 were higher than those without the stimulation （P 〈 0. 05 ） ; （2） in the HE OE-stimulated cells, the level of ROS after transfection with HSF1 was lower than that without transfection （ P 〈 0. 05 ） , while transfection with ASK1 did not induce the change in ROS level. However, the ROS level in the cells transfected with both HSF1 and ASK1 tended to be higher than in those transfected with HSF1 alone; （3） the amplitudes of the change in ROS levels after HEOE-stimulation were paralleled to the results of ROS levels. Conclusions HSF1 can protect cardiac myocytes from oxidative stress through reduction of ROS levels in the cells, which may be interrupted by ASK1.