体内Pig-a基因突变实验评估纳米氧化锌致突变性

Evaluation of mutagenicity of zinc oxide nanoparticles by Pig-a mutation assay in vivo

【目的】利用体内Pig⁃a基因突变实验方法,检测纳米氧化锌(ZnO NPs)颗粒对大鼠遗传毒性的作用。【方法】结合28 d经口毒性试验,设14、70、350 mg‧kg^(−1) ZnO NPs(纳米尺度分散状态最大浓度)3个剂量组、常规ZnO组(350 mg‧kg^(−1) ZnO)、阳性对照组(40 mg‧kg^(−1) N⁃亚硝基⁃N⁃乙基脲)和溶剂对照组(0 mg‧kg^(−1) ZnO NPs),每组各10只大鼠经口灌胃28 d,记录并观察体重变化。在给药0、15、28 d和恢复观察期28 d取各组大鼠尾静脉血200µL,用APC mouse anti⁃rat erythroid cells及FITC mouse anti⁃rat CD59抗体进行标记后,使用流式细胞仪收集各样本1×10^(6)个红细胞信息,计算其中外周血红细胞CD59缺失突变发生率。【结果】与溶剂对照组比较,在灌胃15 d后,350 mg‧kg^(−1) ZnO NPs组、阳性对照组大鼠外周血红细胞CD59缺失突变发生率均升高,差异均有统计学意义(均P<0.01);在灌胃28 d后,70 mg‧kg^(−1) ZnO NPs组、350 mg‧kg^(−1) ZnO NPs组和阳性对照组大鼠红细胞CD59缺失突变发生率均升高,且呈时⁃效和量⁃效关系;在停止灌胃28 d后,除阳性对照组外,其余各组大鼠外周血红细胞CD59缺失发生率与溶剂对照组比较差异均无统计学意义(均P>0.05)。【结论】70、350 mg‧kg^(−1) ZnO NPs会提高大鼠外周血Pig⁃a基因突变率。

[Objective]The genotoxicity of zinc oxide nanoparticles(ZnO NPs)in rats was determined by Pig⁃a mutation assay in vivo.[Methods]Combined with 28-day oral toxicity test,male SD rats were given ZnO NPs by oral administration for 28 days,at doses of 0,14,70 and 350 mg‧kg^(−1)(maximum concentration of nanoscale dispersion state).Rats in control groups received 350 mg‧kg^(−1) of normal size ZnO,40 mg‧kg^(−1) N-ethyl-N⁃nitrosourea(ENU)or 0 mg·kg^(−1) ZnO NPs(solvent control group)Changes of body weight were recorded.At 0,15,28 d and 28 d of recovery observation period,200µL of tail venous blood was collected from each group,which was labeled by APC mouse anti-rat erythroid cells and FITC mouse anti-rat CD59.The information of 1×10^(6) red blood cells(RBC)from each sample were collected by flow cytometry,and the mutation rate of RBC^(CD59-)was calculated.[Results]Compared with the solvent control group,after 15 days of intragastric administration,the mutation rate of RBC^(CD59-) in peripheral blood of in 350 mg‧kg^(−1) ZnO NPs group and 40 mg‧kg^(−1) ENU group was significantly increased while that of in 70 mg‧kg^(−1) ZnO NPs group was also significantly increased after 28 days of intragastric administration.with timeresponse and dose-response relationship.All groups except 40 mg‧kg^(−1) ENU group showed no significant difference in the mutation rate of RBC^(CD59-) in peripheral blood in comparison with the solvent control group after 28-days recovery observation.[Conclusion]70 and 350 mg‧kg^(−1) ZnO NPs can increase the mutation rate of Pig⁃a gene in peripheral blood of SD rats.