不同糖类介质中铬(V)化合物对DNA损伤的影响  

The in vitro Effects of Sugars on Cr-induced DNA Damage.

作　　者：史黎薇[1] 井海宁[1] 任改英[1] Aviva Levina Peter Lay 

机构地区：[1]中国疾病预防控制中心环境与健康相关产品安全所,北京100021 [2]澳大利亚悉尼大学化学所

出　　处：《中国病毒病杂志》2005年第3期32-34,共3页Chinese Journal of Viral Diseases

摘　　要：目的本文对铬〔cr(V)〕中间化合物在糖类介质中与DNA的反应作了初步探索。共研究了在四种糖类及三种不同pH值条件下DNA损伤的情况。DNA的损伤通过凝胶电泳测定。结果表明Cr(V)在糖类介质中具有毒性并可能导致癌症,但不同糖类对DNA的损伤不同,同时随着pH值的增高,DNA的损伤相对较小,这是由于反应体系的酸性增加,cr(V)化合物发生歧化反应的速度加快以及还原剂氢原子浓度的增加所造成的。Objective To investigate the in vitro reactions between Cr(V)-2-hydrocarboxylato complex,(CrO(ehba)_2)(ehba=2-ethyl-2-hydroxybutanoato(2-),and DNA in the presence of sugars.Method The studies were conducted at three pH values(pH=6.5,7.5,8.5)with a range of sugars,including D-glucose and D-glucoseC-d_7.DNA cleavage was observed thugh gel electrophoresis.Results The results of these experiments have reinforced the postulate that Cr(V)complexes are likely to be involved in the genotoxic damage that eventually results in Cr-induced cancers.The formation of Form II DNA showed that Cr(V)complexes were DNA damaging under the studied conditions.Discussion With an increase in the pH values,the amount of Form II DNA decreases due to the increasing rate of Cr(V)disproportion.Onthe other hand,the presence ofsugars in the reaction system inhibited DNA strand cleavage because of H-donor mechanisms and the formation of Cr-mixed-ligand complexes,which stabilised Cr(V)but were less reactive to DNA.

关 键 词：铬〔cr(V)〕中间化合物 DNA损伤 凝胶电泳 

分 类 号：R114[医药卫生—卫生毒理学]