van Gorp R M, Broers J L, Reutelingsperger C P, Bronnenberg N M, Hornstra G, van Dam-Mieras M C, Heemskerk J W
Department of Human Biology, Maastricht University, 6200 MD Maastricht, The Netherlands.
Am J Physiol. 1999 Jul;277(1):C20-8. doi: 10.1152/ajpcell.1999.277.1.C20.
Cells under oxidative stress induced by peroxides undergo functional and morphological changes, which often resemble those observed during apoptosis. Peroxides, however, also cause the oxidation of intracellular reduced glutathione (GSH). We investigated the relation between these peroxide-induced effects by using human umbilical vein endothelial cells (HUVEC) and two HUVEC-derived cell lines, ECRF24 and ECV304. With HUVEC, tert-butyl hydroperoxide (tBH) or hydrogen peroxide application in the presence of serum induced, in a dose-dependent way, reorganization of the actin cytoskeleton, membrane blebbing, and nuclear condensation. These processes were accompanied by transient oxidation of GSH. With ECRF24 cells, this treatment resulted in less blebbing and a shorter period of GSH oxidation. However, repeated tBH addition increased the number of blebbing cells and prolonged the period of GSH oxidation. ECV304 cells were even more resistant to peroxide-induced bleb formation and GSH oxidation. Inhibition of glutathione reductase activity potentiated the peroxide-induced blebbing response in HUVEC and ECRF24 cells, but not in ECV304 cells. Neither membrane blebbing nor nuclear condensation in any of these cell types was due to apoptosis, as evidenced by the absence of surface expression of phosphatidylserine or fragmentation of DNA, even after prolonged incubations with tBH, although high tBH concentrations lead to nonapoptotic death. We conclude that, in endothelial cells, peroxide-induced cytoskeletal reorganization and bleb formation correlate with the degree of GSH oxidation but do not represent an early stage of the apoptotic process.
过氧化物诱导的氧化应激下的细胞会发生功能和形态变化，这些变化通常类似于凋亡过程中观察到的变化。然而，过氧化物也会导致细胞内还原型谷胱甘肽（GSH）的氧化。我们使用人脐静脉内皮细胞（HUVEC）以及两种源自HUVEC的细胞系ECRF24和ECV304，研究了这些过氧化物诱导效应之间的关系。对于HUVEC，在血清存在的情况下施加叔丁基过氧化氢（tBH）或过氧化氢，会以剂量依赖的方式诱导肌动蛋白细胞骨架的重组、膜泡形成和核浓缩。这些过程伴随着GSH的短暂氧化。对于ECRF24细胞，这种处理导致较少的膜泡形成和较短的GSH氧化期。然而，重复添加tBH会增加膜泡形成细胞的数量并延长GSH氧化期。ECV304细胞对过氧化物诱导的膜泡形成和GSH氧化更具抗性。抑制谷胱甘肽还原酶活性会增强过氧化物诱导的HUVEC和ECRF24细胞中的膜泡形成反应，但对ECV304细胞无效。在这些细胞类型中，无论是膜泡形成还是核浓缩都不是由凋亡引起的，这一点通过即使在用tBH长时间孵育后也不存在磷脂酰丝氨酸的表面表达或DNA片段化得以证明，尽管高浓度的tBH会导致非凋亡性死亡。我们得出结论，在内皮细胞中，过氧化物诱导的细胞骨架重组和膜泡形成与GSH氧化程度相关，但不代表凋亡过程的早期阶段。
