纳米氧化锌与常规氧化锌对A549细胞的毒性与DNA损伤的比较研究  

Comparative study on cytotoxicity and DNA damage in A549 cells caused by nano-and micro- zinc oxide particles

作　　者：洪丽玲[1] 丁树娟[1] 朱江波[1] 朱玉平[1] 张天宝[1] 

机构地区：[1]第二军医大学基础部卫生毒理学教研室,上海200433

出　　处：《癌变．畸变．突变》2011年第5期340-343,348,共5页Carcinogenesis,Teratogenesis & Mutagenesis

基　　金：国家重大科学计划子课题(2006CB932505);军特药专项课题(2008ZXJ09014-0095);上海市公共卫生重点学科建设项目(08GWZX0301)

摘　　要：目的:比较纳米氧化锌(Nano-ZnO)和常规氧化锌(Micro-ZnO)对人肺腺癌A549细胞的毒性及DNA损伤作用。方法:采用不同浓度(25、50、100μg/ml)的纳米ZnO(30nm)和常规ZnO(≤1μm)染毒体外培养的A549细胞,实验同时设对照组(DMEM培养液)。分别于染毒后6、12、24、48 h,观察细胞形态及生长情况,采用MTT法和单细胞凝胶电泳技术(彗星实验)检测细胞毒性及对DNA的损伤作用。结果:纳米ZnO和常规ZnO对A549细胞的半数致死浓度(IC_(50))分别为53.91和190.15μg/ml;纳米ZnO在50μg/ml剂量时对A549细胞就已出现明显的生长抑制作用,并呈明显的剂量和时间依赖效应关系;而常规ZnO在100μg/ml剂量时才出现细胞生长的抑制。纳米ZnO与常规ZnO的剂量-效应曲线和时间-效应曲线的斜率比较差异均有统计学意义(P<0.05)。与对照组相比,纳米ZnO能够导致A549细胞产生DNA损伤;常规ZnO在相同受试剂量下未观察到DNA损伤。结论:纳米ZnO与常规ZnO均对体外A549细胞产生细胞毒性,但纳米ZnO产生毒性的剂量低、出现时间早,并产生了常规ZnO未观察到的遗传毒性。OBJECTIVE：To compare the cytotoxicity and DNA damage caused by nano- and micro- zinc oxide particles.METHODS：Cultured A549 human lung adenocarcinoma cells were exposed to nano-（30 nm） and micro-scale ZnO particles（≤1μm） at the concentrations of 25,50 and 100μg/ml for 6,12,24 and 48 h.In the mean time,DMEM culture medium was set up as control.Morphological changes were examined after exposure,methyl tetrazolium cytotoxicity（MTT） assay and the single cell gel electrophoresis（comet assay） were used to determine cytotoxicity and DNA damage.RESULTS：The IC50 of the nano-ZnO and micro-ZnO on the A549 cells were 53.91 and 190.15μg/ml,respectively.It was found that nano-ZnO inhibited A549 cells significantly at 50μg/ml,showing a dose- and time- dependent manner.But micro-ZnO inhibited A549 cells significantly only when the concentration up to 100μg/ml. The slope of the dose-response curve and time-effect curve of the nano-and micro-ZnO was significantly different.In addition,nano-ZnO particles demonstrated a DNA-damaging potential compared to control group in the Comet assay after an exposure of 6 h.Micro-ZnO did not induce any DNA damage.CONCLUSION：Nano- and micro-ZnO particles both demonstrated cytoxicity in A549 cells,but the toxic effects of nano-ZnO occurred earlier in time and lower in dose compared with micro-ZnO.Nano-ZnO particles could induce DNA damage,but the micro- ones did not.

关 键 词：纳米氧化锌 常规氧化锌 A549细胞 细胞毒性 DNA损伤 

分 类 号：R994.6[医药卫生—毒理学]