纳米与微米尺度氧化锌体外遗传毒作用特征的比较研究  

Comparative Study on Genotoxicity in Vitro Caused by Nano-and Micro-Scale ZnO

作　　者：梁春柳[1] 朱江波[2] 朱玉平[2] 姚朗[1] 张天宝[2] 

机构地区：[1]南方医科大学公共卫生与热带医学学院毒理学系,广州510515 [2]第二军医大学卫生毒理学教研室,上海200433

出　　处：《生态毒理学报》2012年第3期299-304,共6页Asian Journal of Ecotoxicology

基　　金：国家重大科学计划子课题(2006CB932505);上海市科委纳米专项基金(0752nm020)

摘　　要：为揭示纳米氧化锌(ZnO)遗传毒作用特征,以便为纳米材料的安全性评价提供科学依据,利用胞质分裂阻滞微核细胞组学实验和碱性彗星实验比较了纳米和微米尺度ZnO的遗传毒性。结果显示:①微米尺度ZnO在0.02～2.5μg·mL-1剂量下对微核、核质桥、核芽和核分裂指数(nucleus divided index,NDI)均无显著诱导作用(P>0.05);而纳米尺度ZnO在>0.5μg·mL-1剂量时可显著诱导细胞产生总微核、Ⅰ型微核和核芽(P<0.05),且均存在一定的剂量-效应关系,剂量为2.5μg·mL-1时,细胞的Ⅱ型微核数、核质桥数和NDI与对照组相比,也呈现出显著差异(P<0.05)。②剂量为2.5μg·mL-1时,处理9、18和24h后,与对照组相比,微米ZnO处理组中细胞各项指标的差异均无统计学意义(P>0.05),而纳米ZnO处理组中总微核数、Ⅰ型微核数和核质桥数具有时间-效应关系。③纳米ZnO在0.5μg·mL-1剂量时可诱导DNA损伤,而微米ZnO在2.5μg·mL-1剂量时才产生损伤效应。研究表明,纳米和微米尺度ZnO在遗传毒作用性质和毒性强弱方面均存在明显差异,纳米ZnO会诱导Ⅰ型、Ⅱ型微核、核芽和核质桥的产生以及DNA损伤,而微米ZnO仅在高剂量时会诱导DNA损伤。Abstract： To investigate the characteristics of genotoxicity of nano-ZnO and so as to provide a scientific ba- sis for safety assessment of nanomaterials, the comparison of genotoxicity between nano- and micro-scale ZnO was conducted using cytokinesis-block micronucleus cytome test and alkaline comet assays in vitro. Re- sults were as follows① Micro-ZnO could not significantly influence the indexes such as micronucleus, nu- cleoplasmic bridge, nuclear bud and nuclear divided index （NDI） at the dosage of 0.02-2.5 μg.mL J（P 〉 0.05）. However, nano-ZnO at the dosage higher than 0.5μg-mL-1 led to an increase in the numbers of total micro- nucleus, type I micronucleus and nuclear bud in a dose-dependent manner （P 〈 0.05）. Compared with the control group, significant differences were observed in the numbers of type Ⅱ micronucleus, nucleoplasmic bridge and NDI in nano-ZnO group with the dosage of 2.5 μg-mL -1（P〈0.05）. ② No significant differenceswere found in all the tested indexes alter exposure to zm Ixg＇mL oi macro-LHt., ~o, 7, ,o ,n,u ^-,, lr, with the control group （P 〉0.05）. However, the numbers of total micronucleus, type I micronucleus and nu- cleoplasmic bridge exhibited a time-effect relationship in nano-ZnO group. ③ Nano-ZnO caused DNA damage at 0.5 Izg＇mL ~, but DNA damage was not observed in micro-ZnO group until the dosage of 2.5 Ixg＂ mL- The study demonstrated that the properties and strength of genotoxicity were significantly different between nano-ZnO and micro-ZnO. Nano-ZnO could induce the generation of type I micronucleus, type 11 micronu- cleus, nuclear bud and nucleoplasmic bridge and cause DNA damage, whereas only DNA damage was caused by micro-ZnO at relatively high doses.

关 键 词：纳米氧化锌 微米氧化锌 彗星实验 微核 核质桥 核芽 

分 类 号：X171.5[环境科学与工程—环境科学]