亚低温干预通过改善线粒体功能抑制干扰素-α2b诱导的人心肌细胞AC16凋亡

Mild Hypothemia Inhibits Interferon-α2b-induced AC16 Cardiomyocytes Apoptosis Via Improving Mitochondrial Function

目的:分析亚低温在Ⅰ型干扰素(干扰素-α2b)诱导的人心肌细胞AC16凋亡过程中的作用及分子机制。方法:不同浓度的干扰素-α2b在不同时间点刺激人心肌细胞AC16,CCK-8检测心肌细胞增殖;流式细胞仪检测干扰素-α2b刺激心肌细胞后常温、亚低温对细胞的影响;线粒体Mito-Tracker绿色荧光探针染色激光共聚焦成像观察线粒体形态的变化;流式细胞仪检测不同干预条件下线粒体膜电位变化情况;通过线粒体Mito-Tracker绿色荧光探针染色激光共聚焦成像评估线粒体动力相关蛋白1(Drp1)与线粒体的共定位情况及不同干预条件对线粒体的影响;使用蛋白免疫印迹法检测不同干预条件下,磷酸化Drp1 Ser616、Drp1、核酶多聚二磷酸腺苷核糖聚合酶1(PARP1)、剪切型PARP1(cleaved-PARP1)蛋白表达变化。结果:CCK-8及流式细胞仪检测发现干扰素-α2b抑制AC16细胞增殖,并可诱导AC16细胞凋亡,亚低温干预发挥心肌保护作用;不同干预条件下,AC16细胞线粒体损伤程度不一,表现为亚低温干预细胞具有较好的线粒体形态和更高的线粒体膜电位;Mito-Tracker绿色荧光探针检测发现心肌细胞损伤时Drp1从胞浆转移至线粒体中参与线粒体分裂,且亚低温干预发挥抑制作用;蛋白免疫印迹法检测发现亚低温干预后磷酸化Drp1 Ser616/Drp1和cleaved-PARP1/PARP1显著降低,且线粒体分裂抑制剂1(Mdivi-1)预处理可部分逆转上述现象。结论:亚低温干预通过改善线粒体功能抑制Ⅰ型干扰素-α2b诱导的人心肌细胞AC16凋亡。

Objectives:To explore the effect and possible mechanisms of mild hypothermia on interferon(IFN)-α2b-induced AC16 cardiomyocytes apoptosis.Methods:Cardiomyocytes were stimulated in ordinary temperature and mild hypothermia by IFN-α2b under different concentrations for different times.Proliferation activity of cardiomyocytes was detected by CCK-8 assay.Apoptosis was detected by flow cytometry technique.The effects of different interventions on mitochondrial morphology were examined using Mito-Tracker Green and laser scanning confocal microscope,respectively.The mitochondrial membrane potentials under different intervention conditions were detected by flow cytometry.The fusion of dynamin-related protein 1(Drp1)and mitochondria,and the effects of different interventions on the mitochondria was examined by Drp1 or mitochondrial fluorescent probes and laser scanning confocal microscope.The effects of different intervention conditions on the protein expression level of Phospho-Drp1(p-Drp1)Ser616,Drp1,cleaved poly ADP-ribose polymerase1(cleaved-PARP1),poly ADPribose polymerase1(PARP1)were detected by Western blot.Results:CCK-8 assay and flow cytometry results showed that IFN-α2b inhibited the proliferation and enhanced the apoptosis of AC16 cardiomyocytes in a time and dose-dependent manner,these effects could be attenuated by mild hypothermia.Mito-Tracker Green,laser scanning confocal microscope and flow cytometry results showed that the extent of damage of mitochondria with different interventions were attenuated in the setting of mild hypothermia as compared with ordinary temperature.The morphology of mitochondria remained intact and the mitochondrial membrane potentials were the highest in mild hypothermia group.Injured AC16 cardiomyocytes released Drp1 from cytoplasm to mitochondria and increased mitochondrial fission,these effects were abolished after mild hypothermia.p-Drp1 Ser616/Drp1 ratio and cleaved-PARP1/PARP1 ratio were decreased after mild hypothermia,and above effects could be reversed by mitochondrial division inhibitor-1(Mdivi-1)pretreatment.Conclusions:Mild hypothermia inhibits IFN-α2b-induced AC16 cardiomyocytes apoptosis via improving mitochondrial function.