青石棉诱导A_L细胞CD59基因突变和DNA氧化损伤的研究  

CD59mutation and DNA oxidative damage in A_L cells indu ced by crocidolite fibers

作　　者：许安[1] 吴李君[1] Hei TK 余增亮[1] 

机构地区：[1]中国科学院等离子体物理研究所离子束生物工程学重点实验室,合肥230031 [2]Center for Radiological Research,College of Physicians and Surgeons,Columbia University,newyork10032

出　　处：《中华劳动卫生职业病杂志》2004年第1期43-46,共4页Chinese Journal of Industrial Hygiene and Occupational Diseases

摘　　要：目的　研究谷胱甘肽合成酶抑制剂buthioninesulfoximine(BSO)和自由基清除剂二甲亚砜 (DMSO)对青石棉诱导人鼠杂交瘤 (AL)细胞CD59基因突变率的影响以及青石棉引发细胞内 8 羟基脱氧鸟苷 (8 OHdG)产生的规律。方法　细胞毒性、遗传毒性检测分别采用克隆法 ;8 OHdG检测采用ABC酶免疫染色法 ;非蛋白巯基化合物 (NPSH)检测采用改进后的Tietze法。结果　 2 5μmol/LBSO预处理AL 细胞 2 4h后的细胞内NPSH含量降为 2nmol/ 10 7细胞 ,仅为对照组的 5%。青石棉单独处理组AL 细胞CD59基因突变率为 2 0 8± 18。BSO预处理 2 4h后与青石棉继续共同孵育组细胞突变率可达到 3 97± 55,是青石棉单独处理组的 2倍左右 ,差异有显著性 (P <0 .0 5) ;而DMSO存在时 ,青石棉诱导的CD59基因突变率仅为 57± 8,比青石棉单独处理组降低 72 .6%。细胞内 8 OHdG的产生随着青石棉处理剂量的增加而线性增加 (y =150 + 2 0x ,r =0 .962 1)。当青石棉处理剂量为 6μg/cm2 时 ,细胞内 8 OHdG含量由对照组的 13 7± 9提高到 2 89± 6,是对照组的 2倍以上。DMSO存在时 ,可使 6μg/cm2 石棉诱导的细胞内 8 OHdG含量由 2 89± 6降低到 170± 3。结论　自由基是青石棉诱导基因突变和DNA损伤过程中重要的调节物 ,具有剂量ObjectiveTo determine the effects of buthi onine sulfoximine(BSO) and free radical scavenger,dimethyl sulfoxide(DMSO),on m utation frequency and the formation of 8-hydroxydeoxyganosine(8-OHdG) induced by crocidolite fibers in human-hamster hybrid(A L) cells. Methods The cytotoxicity and mutagenicity were determined by the formation of colonies.8-OHdG was examined by immunoperoxidase staining.Non-protein sulfh ydryl(NPSH) compound was assayed by modified Tietze's method. Results The level of NPSH in A L cell pretreated with 25 μmol/L of BSO wa s decreased to 2 nmol/10 7 cells,only 5% of the control after 24 h.The mutation frequency of CD59 gene of A L cell in crocidolite alone treated group was 208 ±18 while that in BSO pretreated group(397±55) was about twice the former( P <0.05).The mutation frequency of CD59 gene in the group treated with crocidoli te and in the presence of DMSO(57±8) was 72.6% less than that in crocidolite al one treated group. Crocidolite fibers induced a dose-effect relationship in the formation of 8-OH dG in A L cells( y=150+20x,r= 0.962 1 ) . The level of 8-OHdG in cells was 289±6 at the dose of 6 μg/cm 2 crocidoli te,which was about twice the control group(137±9).In the presence of DMSO,8-OH dG level decreased to 170±3 at the same dose of crocidolite. Conclusion Free radicals are the important inducer ofmutagenesis and DNA damage in A L cells caused by crocidolite,which has dose-e ffect relationship

关 键 词：青石棉 AL细胞 CD59基因 基因突变 DNA氧化损伤 DNA突变 脱氧鸟嘌呤核苷酸类 致癌因子 

分 类 号：R114[医药卫生—卫生毒理学]