Mechanism of DNA damage induced by bromate differs from general types of oxidative stress
Mechanism of DNA damage induced by bromate differs from general types of oxidative stress
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DOI：
10.1016/j.tox.2006.01.002
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发表时间：
2006-04-17
期刊：
影响因子：
4.5
通讯作者：
Murata, M
中科院分区：
文献类型：
--
作者：
Kawanishi, S;Murata, M
活性氧（ROS）的代表羟基自由基（(OH)- o -中心点）是一种高活性物质，可诱导DNA主干断裂。（OH）- o中心点也氧化每个DNA碱基。（OH）- o-中心点与鸟嘌呤的相互作用不仅产生抗哌替啶的8-氧-7,8-二氢-2'-脱氧鸟嘌呤（8-oxodG），而且产生各种哌替啶不稳定产物。另一方面，在谷胱甘肽（GSH）和半胱氨酸（Cys）等SH化合物存在的情况下，溴酸钾（KBrO3）诱导特异性形成8-oxodG。GSH/Cys还原KBrO3 （BrO3-）为BrO2，从鸟嘌呤中提取一个电子。鸟嘌呤的单电子氧化可能产生阳离子自由基，然后与水分子反应，形成8-氧g。因此，溴酸盐诱导DNA氧化损伤的机制不同于(OH)- o -中心点等一般类型的氧化应激。(c) 2006年Aww研究基金。爱思唯尔爱尔兰有限公司出版。版权所有。
A representative reactive oxygen species (ROS), hydroxyl radical ((OH)-O-center dot), is a highly reactive species and induces DNA backbone breakage. (OH)-O-center dot also oxidizes every DNA base. The interaction of (OH)-O-center dot with guanine leads to the generation of not only piperidine-resistant 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) but also various piperidine-labile products. On the other hand, potassium bromate (KBrO3) induces specific formation of 8-oxodG in the presence of SH compounds, such as glutathione (GSH) and cysteine (Cys). GSH/Cys reduces KBrO3 (BrO3-) to BrO2, which abstracts one electron from guanine. The one-electron oxidation of guanine may yield cation radicals followed by the reaction with a water molecule, leading to 8-oxodG formation. Therefore, mechanism of bromate-induced oxidative DNA damage is different from general types of oxidative stress such as (OH)-O-center dot. (c) 2006 Aww Research Foundation. Published by Elsevier Ireland Ltd. All rights reserved.