Autor: |
Shi, Xianglin, Mao, Yan, Knapton, Alan D., Ding, Min, Rojanasakul, Yongyut, Gannett, Peter M., Dalal, Naresh, Liu, Kejian |
Zdroj: |
Carcinogenesis; 1994, Vol. 15 Issue 11, p2475-2478, 4p |
Abstrakt: |
Incubation of Cr(VI) with ascorbate generated Cr(V), Cr(IV) and ascorbate-derived carbon-centered alkyl radicals, as well as formyl radicals. HO caused generation of hydroxyl radicals (·OH) and much higher levels of Cr(V), showing that ·OH can be generated via a (Cr(IV)-mediated Fenton-like reaction (Cr(IV) + HO→Cr(V)+ ·OH + OH). 1,10-Phenanthroline and deferoxamine inhibited the formation of both OH and Cr(V) from the reaction of Cr(VI) with ascorbate in the presence of HO. Electro phoretic assays showed that ascorbate-derived free radicals caused DNA double-strand breaks. OH radicals generated by Cr(V)- and Cr(IV)-medlated Fenton-like reactions also caused DNA double-strand breaks. HPLC measurements showed that ·OH radicals generated by Cr(IV) and Cr(V) from HO caused 2′-deoxyguanlne hydroxylatlon to form 8-hydroxy-2′-deoxyguanine. [ABSTRACT FROM PUBLISHER] |
Databáze: |
Complementary Index |
Externí odkaz: |
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