Cell death during ischemia: relationship to mitochondrial depolarization and ROS generation
Cell death during ischemia: relationship to mitochondrial depolarization and ROS generation
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DOI：
10.1152/ajpheart.00708.2002
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发表时间：
2003-02-01
影响因子：
4.8
通讯作者：
Schumacker, PT
中科院分区：
文献类型：
--
作者：
Levraut, J;Iwase, H;Schumacker, PT
缺血再灌注损伤诱导细胞死亡，但其机制尚不清楚。本研究检测了缺血和再灌注过程中线粒体去极化和细胞死亡。收缩心肌细胞进行60分钟的缺血，然后3小时的再灌注。用四甲基罗丹明甲酯评估线粒体膜电位（DeltaPsi（m））。在缺血期间，Δ Psi（m）降低至基线的24 +/-5.5%，但在再灌注期间没有明显的恢复。Sytox绿色评估的细胞死亡在缺血期间是最小的，但在3小时再灌注后平均为66 +/- 7%。环孢菌素A，一种线粒体通透性转换的抑制剂，没有保护作用。然而，药理学抗氧化剂减弱了缺血期间DeltaPsi（m）的下降和再灌注后的细胞死亡，并降低了脂质过氧化作用，如C11-BODIPY所评估的。当从灌注液中清除残留的O-2时，细胞死亡也减弱，从而产生缺氧缺血。这些结果表明，活性氧（ROS）是重要的减少DeltaPsi（m）在缺血期间。最后，缺乏线粒体电子传递链的143 B-rho（0）骨肉瘤细胞在缺血期间未能证明DeltaPsi（m）的耗尽，并且在再灌注期间显著保护免于细胞死亡。总的来说，这些研究确定了缺血期间线粒体ROS产生在该模型中由缺血和再灌注诱导的线粒体去极化和随后的细胞死亡中的核心作用。
Ischemia-reperfusion injury induces cell death, but the responsible mechanisms are not understood. This study examined mitochondrial depolarization and cell death during ischemia and reperfusion. Contracting cardiomyocytes were subjected to 60-min ischemia followed by 3-h reperfusion. Mitochondrial membrane potential (DeltaPsi(m)) was assessed with tetramethylrhodamine methyl ester. During ischemia, DeltaPsi(m) decreased to 24 +/- 5.5% of baseline, but no recovery was evident during reperfusion. Cell death assessed by Sytox Green was minimal during ischemia but averaged 66 +/- 7% after 3-h reperfusion. Cyclosporin A, an inhibitor of mitochondrial permeability transition, was not protective. However, pharmacological antioxidants attenuated the fall in DeltaPsi(m) during ischemia and cell death after reperfusion and decreased lipid peroxidation as assessed with C11-BODIPY. Cell death was also attenuated when residual O-2 was scavenged from the perfusate, creating anoxic ischemia. These results suggested that reactive oxygen species (ROS) were important for the decrease in DeltaPsi(m) during ischemia. Finally, 143B-rho(0) osteosarcoma cells lacking a mitochondrial electron transport chain failed to demonstrate a depletion of DeltaPsi(m) during ischemia and were significantly protected against cell death during reperfusion. Collectively, these studies identify a central role for mitochondrial ROS generation during ischemia in the mitochondrial depolarization and subsequent cell death induced by ischemia and reperfusion in this model.