Fast repair of dAMP hydroxyl radical adduct by verbascoside via electron transfer

作     者：石益民 王文锋 姚思德 林维真 韩镇辉 师彦平 贾忠建 郑荣梁 

出 版 物：《Science China(Life Sciences)》 (中国科学（生命科学英文版）)

年 卷 期：1999年第42卷第6期

页      面：621-627页

学科分类：1001[医学-基础医学(可授医学、理学学位)] 10[医学] 

基　　金：Project supported partly by the National Natural Science Foundation of China the Doctoral Programme of the Ministry of Education of China the China Postdoctoral Sciences Foundation the Laboratory of Radiation Chemistry the Chinese Academy 

主　　题：DNA damage dAMP hydroxyl radical verbascoside electron transfer fast repair. 

摘      要：DNA damaged by oxygen radicals has been implicated as a causative event in a number of degenerative diseases, including cancer and aging. So it is very impotant to look for ways in which either oxygen radicals are scavenged prior to DNA damage or damaged DNA is repaired to supplement the cells inadequate repair capacity. The repair activity and its mechanism of verbascoside, isolated from Pedicularis species, towards dAMP-OH· was studied with pulse radiolytic technique. On pulse irradiation of nitrous oxide saturated 2 mmol/L dAMP aqueous solution containing verbascoside, the transient absorption spectrum of the hydroxyl adduct of dAMP decayed with the formation of that of the phenoxyl radical of verbascoside well under 100 microseconds after electron pulse irradiation. The result indicated that dAMP hydroxyl adducts can be repaired by verbascoside. The rate constants of the repair reaction was deduced to be 5.9 x 108 dm3 · mol-1 · s-1 . A deeper understanding of this new repair mechanism will undoubtedly help researchers explore new prevent and/or intervening medicine.