Cytochrome c is a potent catalyst of dichlorofluorescin oxidation:: Implications for the role of reactive oxygen species in apoptosis
Cytochrome c is a potent catalyst of dichlorofluorescin oxidation:: Implications for the role of reactive oxygen species in apoptosis
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DOI：
10.1006/bbrc.2001.4578
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发表时间：
2001-03-23
影响因子：
3.1
通讯作者：
Wardman, P
中科院分区：
文献类型：
--
作者：
Burkitt, MJ;Wardman, P
活性氧的产生已被认为是发生在细胞凋亡的增加率，但有效性和意义，这仍然存在争议。在几项关键研究中，使用细胞内探针二氯荧光素（DCFH 2）监测活性氧物质的水平，该探针氧化为荧光二氯荧光素（DCF）。我们在这里报告，细胞色素c，这是从线粒体在细胞死亡过程中释放，是一个有力的催化剂的DCF形成。在使用黄嘌呤氧化酶产生超氧自由基的模型系统中，DCF形成的速率对超氧化物产生速率的变化不敏感，但对纳摩尔浓度的细胞色素c非常敏感。因此，我们得出结论，在垂死的细胞中观察到的DCF荧光是增加的胞质细胞色素c的反映。此外，我们认为，抗凋亡癌蛋白Bcl-2抑制DCF形成，这已被认为具有抗氧化特性，可以解释其预防线粒体细胞色素c释放的基础上，（C）2001年学术出版社。
The generation of reactive oxygen species has been suggested to occur at increased rates during apoptosis, but the validity and significance of this remain contentious. In several key studies levels of reactive oxygen species have been monitored using the intracellular probe dichlorofluorescin (DCFH2), which undergoes oxidation to the fluorescent dichlorofluorescein (DCF). We report here that cytochrome c, which is released from mitochondria during cell death, is a potent catalyst of DCF formation. In a model system using xanthine oxidase to generate superoxide radicals, the rate of DCF formation was insensitive to changes in the rate of superoxide production over a 17-fold range, but extremely sensitive to nanomolar concentrations of cytochrome c. Thus we conclude that the DCF fluorescence observed in dying cells is a reflection of increased cytosolic cytochrome c. Moreover, we suggest that the suppression of DCF formation by the anti-apoptotic oncoprotein Bcl-2, which has been suggested to have antioxidant properties, can be explained on the basis of its prevention of mitochondrial cytochrome c release, (C) 2001 Academic Press.