Chiou Tzeon-Jye, Chu Sin-Tak, Tzeng Woan-Fang
Section of Medical Oncology, Department of Medicine, Veterans General Hospital, Taipei, Taiwan ROC.
Toxicology. 2003 Sep 30;191(2-3):77-88. doi: 10.1016/s0300-483x(03)00189-6.
Menadione is a commonly used compound that causes oxidative stress. We investigated the influence of lipid peroxidation on the apoptotic response of mouse myogenic C2C12 cells following menadione-induced oxidative stress. The presence of hypodiploid cells and phosphatidylserine translocation were assayed to detect apoptotic cells. Menadione at 10-40 micro M induced cell apoptosis. Menadione at dose of 80 micro M induced both apoptosis and necrosis. At a 160 micro M dosage, menadione induced cell necrosis. Caspase 3 activation is required for menadione-induced apoptosis. Incubation of cells with 40 micro M menadione resulted in the depletion of cellular glutathione and increased lipid peroxidation. Pre-treatment of cells with cysteine suppressed the menadione-induced apoptosis and prevented changes in reactive oxygen species levels, glutathione levels and lipid peroxidation. Pre-treatment of cells with deferoxamine mesylate, an iron chelator, also reduced both menadione-induced apoptosis and lipid peroxidation. However, this did not prevent menadione-induced glutathione depletion. Thus, the inhibition of lipid peroxidation by deferoxamine mesylate prevented apoptosis even though cellular glutathione remained depleted. Our data suggest that menadione-induced apoptosis is directly linked to iron-dependent lipid peroxidation.
甲萘醌是一种常用的可引起氧化应激的化合物。我们研究了脂质过氧化对甲萘醌诱导的氧化应激后小鼠成肌C2C12细胞凋亡反应的影响。通过检测亚二倍体细胞的存在和磷脂酰丝氨酸易位来检测凋亡细胞。10 - 40微摩尔的甲萘醌诱导细胞凋亡。80微摩尔剂量的甲萘醌诱导凋亡和坏死。甲萘醌诱导的凋亡需要半胱天冬酶3激活。用40微摩尔甲萘醌孵育细胞导致细胞内谷胱甘肽耗竭并增加脂质过氧化。用半胱氨酸预处理细胞可抑制甲萘醌诱导的凋亡，并防止活性氧水平、谷胱甘肽水平和脂质过氧化的变化。用铁螯合剂甲磺酸去铁胺预处理细胞也可减少甲萘醌诱导的凋亡和脂质过氧化。然而，这并不能阻止甲萘醌诱导的谷胱甘肽耗竭。因此，即使细胞内谷胱甘肽仍然耗竭，甲磺酸去铁胺对脂质过氧化的抑制也能阻止凋亡。我们的数据表明，甲萘醌诱导的凋亡与铁依赖性脂质过氧化直接相关。
