Acute energy reduction induces caspase-dependent apoptosis and activates p53 in retinal ganglion cells (RGC-5)
Acute energy reduction induces caspase-dependent apoptosis and activates p53 in retinal ganglion cells (RGC-5)
复制标题
急性能量减少会诱导 caspase 依赖性细胞凋亡并激活视网膜神经节细胞 (RGC-5) 中的 p53。
DOI：
10.1016/j.exer.2009.06.004
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发表时间：
2009-10-01
影响因子：
3.4
通讯作者：
Su, Guan-Fang
中科院分区：
文献类型：
--
作者：
Li, Guang-Yu;Fan, Bin;Su, Guan-Fang
能量减少引起的视网膜神经节细胞死亡与许多眼科疾病有关。本研究旨在探讨葡萄糖剥夺（GD）急性ATP还原后视网膜神经节细胞（RGC-5）的凋亡途径。RGC-5细胞在无糖或正常DMEM中培养3天。采用ATP法和MTT法检测细胞内ATP和细胞活力的变化。APOPercentage （TM）和原位TUNEL法测定细胞死亡模式。通过测量细胞内ROS的生成、HO-1的表达、抗氧化剂的作用以及GSSG与总GSH的比例来评估氧化应激的参与。Western blotting检测p53和凋亡标志物的激活情况。我们发现，葡萄糖剥夺引起细胞内ATP水平的急性下降，同时降低细胞活力。细胞死亡表现出凋亡的典型特征，包括细胞萎缩、磷脂酰丝氨酸外化和DNA断裂。氧化应激参与细胞死亡过程；一种抗氧化剂显著地保护细胞免受葡萄糖剥夺。RGC-5细胞在无糖培养基中培养32 h后，p53和凋亡标志物caspase-3、PARP-1被激活，泛caspase抑制剂Z-VAD-fmk足以阻止细胞凋亡。这些结果表明，葡萄糖剥夺引起的急性能量减少会触发caspase依赖性细胞凋亡并激活p53。阻断这一细胞死亡途径的关键步骤可能具有治疗作用，使视网膜神经节细胞免受急性能量减少相关的损伤。2009爱思唯尔有限公司版权所有。
The energy reduction-induced death of retinal ganglion cells is associated with many ophthalmic diseases. The present study was designed to investigate the apoptosis pathway of retinal ganglion cells (RGC-5) following acute ATP reduction by using glucose deprivation (GD). RGC-5 cells were cultured in glucose-free or normal DMEM for 3 days. The changes in intracellular ATP and cell viability were monitored by ATP assay and MTT assay. APOPercentage (TM) and in situ TUNEL assays were used to determine the cell death pattern. The involvement of oxidative stress was assessed by measuring intracellular ROS generation, the HO-1 expression, the effect of antioxidants, and the ratio of GSSG to total GSH. The activation of p53 and apoptosis markers was evaluated by Western blotting. We found that glucose deprivation caused an acute decline of intracellular ATP level, concomitantly decreasing cell viability. The cell death exhibited typical features indicative of apoptosis, including cell shrinkage, phosphatidylserine externalization and DNA fragmentation. Oxidative stress was involved in the cell death process; an antioxidant significantly protected the cells against glucose deprivation. p53 and apoptosis markers, caspase-3 and PARP-1 were activated after RGC-5 cells were cultured in glucose-free media for 32 h. Z-VAD-fmk, a pan-caspase inhibitor, was sufficient to prevent apoptosis. These results suggest that acute energy reduction induced by glucose deprivation triggers caspase-dependent apoptosis and activates p53. Blocking the critical steps in this cell death pathway may have therapeutic effects, rescuing the retinal ganglion cells from damages associated with acute energy reduction. (C) 2009 Elsevier Ltd. All rights reserved.