摘要
[目的]研究纳米二氧化钛(nano-TiO_2)对氯化镉(CdCl_2)所致人胚肝细胞毒性作用的影响。[方法]不同浓度的CdCl_2(0.001、0.01、0.1μmol/L)单独或与0.01 mg/L nano-TiO_2混合后,分别作用于人胚肝L-02细胞24h,观察各组L-02细胞的DNA损伤水平,以及hMsh2基因(hMsh2)、O^6-甲基鸟嘌呤甲基转移酶(MGMT)和DNA依赖蛋白激酶复合物催化亚基(DNA-PKcs)的mRNA表达水平。[结果]与相应剂量的CdCl_2单独染毒组比较,nano-TiO_2与各浓度的CdCl_2混合染毒组L-02细胞的DNA损伤加重(P<0.05),hMsh2表达水平明显上升(P<0.05),MGMT表达水平无显著性变化,nano-TiO_2与0.01、0.1μmol/L的CdCl_2混合染毒组DNA-PKcs的基因表达水平明显上升(P<0.05)。[结论]0.01mg/L的nano-TiO_2可以加重各浓度CdCl_2对L-02细胞的DNA单链损伤,从而使CdCl_2对L-02细胞毒性作用增强。
[ Objective ] To investigate the influence of nano-TiO2 on the toxic effects of cadmium chloride in human embryo liver L-02 cell line. [ Methods ] L-02 cells were exposed to different concentration of cadmium chloride（ 0.001,0.01, 0.1 μmol/L ）, or different concentration of cadmium chloride ＋ nano-TiO2 （ 0.01 mg/L ） respectively for 24 hours. DNA damage level was detected by comet assay. The expression level of DNA repair enzymes O^6-methylguanine-DNA methyltransferase （ MGMT ）, DNA-dependent protein kinase catalytic subunit （ DNA-PKcs ） and hMsh2 were measured by RT-PCR. [ Results ] Compared with the corresponding cadmium chloride exposed groups, 0.001,0.01, 0.1 μmol/L cadmium chloride ＋ nano-TiO2（ 0.01 μmol/L ） increased DNA damage level and the expression level of hMsh2 respectively （ P 〈 0.05 ）; while 0.01, 0.1 μmol/L cadmium chloride ＋ nano-TiO2 （ 0.01 mg/L ）increased the expression level of DNA-PKcs respectively （ P 〈 0.05 ）, but no significant effect on the expression level of MGMT was observed. [ Conclusion ] 0.01 mg/L nano-TiO2 could aggravate the toxicity induced by cadmium chloride in L-02 cell line.
出处
《环境与职业医学》
CAS
北大核心
2008年第3期256-258,共3页
Journal of Environmental and Occupational Medicine
基金
国家自然科学基金项目(编号:20407010)
教育部新世纪优秀人才支助计划(编号:NCET-06-0640)
