期刊
FREE RADICAL BIOLOGY AND MEDICINE
卷 46, 期 9, 页码 1283-1297出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.freeradbiomed.2009.02.008
关键词
Mitochondria; Free radical; Respiration; Oxidative stress; Hydrogen peroxide; Superoxide radical
资金
- Fundocao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)
- John Simon Guggenhein Memorial Foundation and Conselho Nacional de Pesquisa e Tecnologia (CNPq)
- Instituto Nacional de Ciencia e Tecnologia de Processos Redox em Biomedicina(Redoxoma)
Reactive oxygen species are a by-product of mitochondrial oxidative phosphorylation, derived from a small quantity of superoxide radicals generated during electron transport. We conducted a comprehensive and quantitative study of oxygen consumption, inner membrane potentials, and H2O2 release in mitochondria isolated from rat brain, heart, kidney, liver, and skeletal muscle, using various respiratory substrates (alpha-ketoglutarate, glutamate, succinate, glycerol phosphate, and palmitoyl carnitine). The locations and properties of reactive oxygen species formation were determined using oxidative phosphorylation and the respiratory chain modulators oligomycin, rotenone, myxothiazol, and antimycin A and the Uncoupler CCCP. We found that in mitochondria isolated from most tissues incubated under physiologically relevant conditions, reactive oxygen release accounts for 0.1-0.2% of O-2 consumed. Our findings support an important participation of flavoenzymes and complex III and a substantial role for reverse electron transport to complex I as reactive oxygen species sources. Our results also indicate that succinate is an important substrate for isolated mitochondrial reactive oxygen production in brain, heart, kidney, and skeletal muscle, whereas fatty acids generate significant quantities of oxidants in kidney and liver. Finally, we found that increasing respiratory rates is an effective way to prevent mitochondrial oxidant release under many, but not all, conditions. Altogether, our data uncover and quantify many tissue-, substrate-, and site-specific characteristics of mitochondrial ROS release. (C) 2009 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据