砷对人淋巴细胞DNA氧化损伤的作用  

Application of SCGE-FPG in the study of arsenic-induced oxidative DNA damage in PHA-stimulated and unstimulated human lymphocytes

作　　者：李达圣 Kanehisa Morimoto Tatsuya Takeshita 吕玉泉[2] 

机构地区：[1]贵州省卫生防疫站地方病防治所,贵阳550004 [2]日本大阪大学医学部环境医学教室

出　　处：《中华预防医学杂志》2002年第1期12-15,共4页Chinese Journal of Preventive Medicine

基　　金：国家留学基金委 ( 2 0 0 0年度 )资助 ( 9895 2 0 10 )

摘　　要：目的　探讨砷 (As)引起植物血凝集素 (PHA)刺激和无刺激人外周血淋巴细胞DNA氧化性损伤。方法　用 10 μmol/L砷处理细胞 2h ,经单细胞凝胶电泳 (SCGE ,或彗星试验 ) FPG(甲酰胺基嘧啶 DNA糖基化酶 )消化法检测砷引起的DNA碱基损伤。结果　砷引起的DNA链断裂的修复过程与过氧化氢 (H2 O2 )引起的修复过程类似。FPG消化产生的单链断裂 ,或砷引起的碱基损伤在PHA刺激淋巴细胞较未刺激细胞显著。在PHA刺激的淋巴细胞 ,砷和H2 O2 引起的DNA链断裂 2h分别修复 63 %和 68% ,但在未刺激细胞分别修复大约 3 4 %和 4 3 %。在PHA刺激的淋巴细胞 ,砷和H2 O2引起的碱基损伤 2h分别修复 4 0 %和 4 9% ,但在未刺激细胞分别修复大约 19%和 2 1%。结论　微量砷可引起人类细胞DNA氧化性损伤。损伤的碱基主要是嘌呤或甲酰胺基嘧啶。未分裂 (刺激 )淋巴细胞修复砷与H2 O2Objective To confirm that arsenic (As) induces oxidative DNA damage in phytohemagglutinin (PHA) stimulated and unstimulated human lymphocytes Methods The alkaline comet assay combined with specific enzyme (Formamidopyrimidine DNA glycosylase,FPG) digestion was used to measure As induced base damage Results The enzyme sensitive sites were readily detected with the alkaline comet assay after the cells were treated with 10 μmol As for 2 hours The repair patterns observed for FPG created DNA single strand breaks (SSBs) in As treated cells were comparable to those in hydrogen peroxide (H 2O 2) treated cells The enzyme created SSBs,As induced base damage,were more significantly revealed in PHA stimulated lymphocytes About 63% and 68% of SSBs induced by As and H 2O 2,respectively,were repaired in PHA stimulated lymphocytes by 2 hour repair incubation,but about 34% and 43%,respectively,were repaired in unstimulated cells About 40% and 49% of base damage induced by As and H 2O 2, respectively,were repaired in PHA stimulated lymphocytes,but about 19% and 21 %,respectively,were repaired in unstimulated cells Conclusions As induces oxidative DNA damage in human lymphocytes within micromolar concentrations Like the damage induced by H 2O 2, As induced DNA damage was more slowly repaired in unstimulated lymphocytes

关 键 词：砷 彗星试验 DNA损伤 淋巴细胞 核苷酶类 

分 类 号：R114[医药卫生—卫生毒理学]