Generation of superoxide anion by mitochondria and impairment of their functions during anoxia and reoxygenation in vitro
Generation of superoxide anion by mitochondria and impairment of their functions during anoxia and reoxygenation in vitro
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DOI：
10.1016/s0891-5849(98)00148-8
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发表时间：
1998-12-01
影响因子：
7.4
通讯作者：
Sluse, FE
中科院分区：
文献类型：
--
作者：
Du, G;Mouithys-Mickalad, A;Sluse, FE
有氧细胞消耗的一小部分氧在线粒体呼吸链水平上转化为超氧阴离子。如果产生过量，这种有害的自由基被认为会损害细胞结构和功能。器官缺血再灌注后线粒体水平的损伤已被报道。然而，体内系统的复杂性阻碍了理解和描述线粒体损伤的精确机制和位置。采用体外离体线粒体缺氧-再氧化模型，研究线粒体氧化磷酸化水平下超氧阴离子的产生及其特异性损伤。用电子顺磁共振自旋俘获法对pobn -乙醇进行超氧阴离子的检测。线粒体呼吸参数计算从氧气消耗痕迹记录与克拉克电极。呼吸线粒体在非应激条件下产生超氧阴离子，但在缺氧后再氧化过程中产生超氧阴离子。一些呼吸参数在复氧后受损，表现为磷酸化和非偶联呼吸速率和ADP/O比率的降低以及静息呼吸的增加。POBN对线粒体功能的部分保护表明，功能损伤与体外线粒体产生超氧阴离子有关。(C) 1998爱思唯尔科学有限公司
A small portion of the oxygen consumed by aerobic cells is converted to superoxide anion at the level of the mitochondrial respiratory chain. If produced in excess, this harmful radical is considered to impair cellular structures and functions. Damage at the level of mitochondria have been reported after ischemia and reperfusion of organs. However, the complexity of the in vivo system prevents from understanding and describing precise mechanisms and locations of mitochondrial impairment. An in vitro model of isolated-mitochondria anoxia-reoxygenation is used to investigate superoxide anion generation together with specific damage at the level of mitochondrial oxidative phosphorylation. Superoxide anion is detected by electron paramagnetic resonance spin trapping with POBN-ethanol. Mitochondrial respiratory parameters are calculated from oxygen consumption traces recorded with a Clark electrode. Respiring mitochondria produce superoxide anion in unstressed conditions, however, the production is raised during postanoxic reoxygenation. Several respiratory parameters are impaired after reoxygenation, as shown by decreases of phosphorylating and uncoupled respiration rates and of ADP/O ratio and by increase of resting respiration. Partial protection of mitochondrial function by POBN suggests that functional damage is related and secondary to superoxide anion production by the mitochondria in vitro. (C) 1998 Elsevier Science Inc.