DNA单链断裂与8-羟基脱氧鸟苷生成在镉所致人胚肾上皮细胞毒性作用分析  

Effect of DNA single strand breaks and 8-OHd G production on cadmium-induced toxicity on human embryonic kidney epithelial cells

作　　者：吴礼康[1] 陈嘉兴[2] 田亚锋[1] 鲜敏[1] 邹志辉[2] 陈智健[2] 余日安[2] 

机构地区：[1]深圳市宝安区疾病预防控制中心,广东深圳518101 [2]广东药科大学公共卫生学院,广州510310

出　　处：《中国职业医学》2016年第4期424-428,共5页China Occupational Medicine

基　　金：深圳市科技计划项目(JCYJ20140414154847275)

摘　　要：目的研究镉对人胚肾上皮细胞（HEK）DNA单链断裂与8-羟基脱氧鸟苷（8-OHdG）生成的影响。方法取对数生长期HEK细胞,分为0.0、2.5、5.0、10.0和20.0μmol/L组,分别以相应终浓度的氯化镉染毒24、48和72 h后,收获细胞,采用单细胞凝胶电泳技术检测细胞DNA单链断裂情况,采用酶联免疫吸附法检测细胞内8-OHdG水平。结果 HEK细胞Olive尾距在染毒处理的主效应上有统计学意义（P〈0.01）;其中,HEK细胞Olive尾距在氯化镉染毒剂量为5.0μmol/L时即开始出现较0.0μmol/L组有统计学意义的增长（P〈0.05）;当氯化镉染毒剂量为2.5-10.0μmol/L时,HEK细胞Olive尾距呈随着染毒剂量增加而增加的剂量-效应关系（P〈0.05）。HEK细胞尾部DNA百分率在染毒处理和染毒时间的交互效应上有统计学意义（P〈0.01）;其中,在染毒24 h时间点、当氯化镉染毒剂量为2.5-10.0μmol/L时,以及在染毒48 h时间点、当氯化镉染毒剂量为5.0-20.0μmol/L时,HEK细胞尾部DNA百分率均呈随着氯化镉染毒剂量升高而升高的剂量-效应关系（P〈0.05）;而20.0μmol/L组HEK细胞的尾部DNA百分率在24、48和72 h 3个时间点上,均呈随着染毒时间增加而升高的时间-效应关系（P〈0.05）。HEK细胞内8-OHdG水平在染毒处理的主效应上有统计学意义（P〈0.05）;其中,HEK细胞内8-OHdG水平在氯化镉染毒剂量为10.0μmol/L时才出现较0.0μmol/L组有统计学意义的升高（P〈0.05）。经氯化镉处理后,HEK细胞的尾长、尾/头长比以及细胞内8-OHdG水平均与氯化镉染毒不存在剂量-效应关系和时间-效应关系的改变。结论氯化镉可同时引起HEK细胞发生一定程度的DNA单链断裂与8-OHdG生成;相对于8-OHdG,DNA单链断裂在更低镉染毒剂量下即可出现明显变化,可能与DNA单链断裂比8-OHdG对镉毒性更为敏感有关。Objective To explore the effects of cadmium chloride（ CdCl_2） on DNA single strand breaks and the production of 8-hydroxy-2＇-deoxyguanosine（ 8-OHdG） in human embryonic kidney epithelial cells（ HEK cells）. Methods HEK cells in logarithm growth phase were divided into 5 groups and incubated with the different concentrations of CdCl_2（ 0. 0,2. 5,5. 0,10. 0 and 20. 0 μmol/L） for 24,48 and 72 hours in vitro. After harvesting the cells,DNA single strand breaks was tested by single cell gel electrophoresis,and the level of 8-OHdG was measured using the enzyme linked immunosorbent assay. Results The Olive tail moment was statistically significant in the main effect of CdCl_2 exposed HEK cells（ P〈0. 01）. Among them,when HEK cells were exposed to 5. 0 μmol / L of CdCl_2,the Olive tail moment began to have a statistical significant increasing trend compared with the 0. 0 μmol / L group（ P〈0. 05）; when CdCl_2 concentration was 2. 5-10. 0 μmol / L,the Olive tail moment lengthened with the increasing dose of cadmium exposure,showing a doseeffect relationship（ P〈0. 05）. The tail DNA% was statistically significant in the interaction between exposure treatment and exposure time in HEK cells（ P〈0. 01）. Among them,when CdCl_2 concentration was at 2. 5-10. 0 μmol / L at 24 hours time point and 5. 0-20. 0 μmol / L at 48 hours time point,the tail DNA% raised with the increasing dose of cadmium exposure,showing a dose-effect relationship（ P〈0. 05）. The tail DNA% at 3 time points of 24,48 and 72 hours after exposure to 20. 0 μmol / L of CdCl_2 in HEK cells increased with the increasing time of cadmium exposure,showing a timeeffect relationship（ P〈0. 05）. The level of 8-OHdG had statistical significance in the main effect of CdCl_2 exposure treatment in HEK cells（ P〈0. 05）. Among them,the level of 8-OHdG was first significantly increased only after exposure to 10. 0 μmol / L CdCl_2 compared with the 0. 0 μmol / L group（ P〈0. 05）. After treatment with Ca Cl2,there

关 键 词：氯化镉 人胚肾上皮细胞 DNA损伤 8-羟基脱氧鸟苷 

分 类 号：R114[医药卫生—卫生毒理学] R135.1[医药卫生—公共卫生与预防医学]