AN ELECTRON-PARAMAGNETIC RESONANCE STUDY OF THE INTERACTIONS BETWEEN THE ADRIAMYCIN SEMIQUINONE, HYDROGEN-PEROXIDE, IRON-CHELATORS, AND RADICAL SCAVENGERS
AN ELECTRON-PARAMAGNETIC RESONANCE STUDY OF THE INTERACTIONS BETWEEN THE ADRIAMYCIN SEMIQUINONE, HYDROGEN-PEROXIDE, IRON-CHELATORS, AND RADICAL SCAVENGERS
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DOI：
10.1016/0003-9861(91)90023-c
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发表时间：
1991-04-01
影响因子：
3.9
通讯作者：
MASON, RP
中科院分区：
文献类型：
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作者：
KALYANARAMAN, B;MOREHOUSE, KM;MASON, RP
采用直接电子顺磁共振和自旋捕集技术研究了阿霉素半醌在黄嘌呤/黄嘌呤氧化酶体系中对过氧化氢的厌氧还原反应。在这些条件下，阿霉素半醌似乎与过氧化氢反应，在螯合剂如乙二胺四乙酸和二亚乙基三胺五乙酸存在下形成羟基自由基。在不存在螯合剂的情况下，形成相关但未知的氧化剂。在去铁胺存在下，阿霉素半醌在过氧化氢存在下不会以可检测的速率消失。因此，在阿霉素半醌催化的过氧化氢还原过程中，外源铁的存在是有牵连的。用自旋捕集法分别检测到乙醇和甲酸根生成α-羟乙基自由基和二氧化碳自由基阴离子。羟基自由基和相关的氧化剂与这些清除剂反应，形成相应的自由基。在形成还原自由基的清除剂存在下，该体系中过氧化氢的消耗速率增加。这一结果可以用自由基驱动的芬顿反应来解释。
Anaerobic reduction of hydrogen peroxide in a xanthine/xanthine oxidase system by adriamycin semiquinone in the presence of chelators and radical scavengers was investigated by direct electron paramagnetic resonance and spin trapping techniques. Under these conditions, adriamycin semiquinone appears to react with hydrogen peroxide forming the hydroxyl radical in the presence of chelators such as ethylenediaminetetraacetic acid and diethylenetriaminepentaacetic acid. In the absence of chelators, a related, but unknown oxidant is formed. In the presence of desferrioxamine, adriamycin semiquinone does not disappear in the presence of hydrogen peroxide at a detectable rate. The presence of adventitious iron is therefore implicated during adriamycin semiquinone-catalyzed reduction of hydrogen peroxide. Formation of α-hydroxyethyl radical and carbon dioxide radical anion from ethanol and formate, respectively, was detected by spin trapping. Both the hydroxyl radical and the related oxidant react with these scavengers, forming the corresponding radical. In the presence of scavengers from which reducing radicals are formed, the rate of consumption of hydrogen peroxide in this system is increased. This result can be explained by a radicaldriven Fenton reaction.