大气可吸入颗粒物致HepG2细胞DNA损伤  

Study on DNA damage of HepG2 cell induced by inhalable particulate matter

作　　者：姜丽平[1] 戴红[2] 耿成燕[1] 杨月 吴涛 曹军[2] 仲来福[1] 

机构地区：[1]大连医科大学-中日合作医药科学研究所,辽宁大连116044 [2]大连医科大学劳动卫生与环境卫生学教研室 [3]大连市环境科学学会

出　　处：《中国公共卫生》2009年第7期847-849,共3页Chinese Journal of Public Health

基　　金：国家自然科学基金(30771820);大连市环保护局科技计划项目(HK200501-02)

摘　　要：目的研究大气可吸入颗粒物(PM10)致人肝细胞瘤细胞(HepG2)DNA损伤及其可能机制。方法单细胞凝胶电泳(SCGE)试验检测细胞DNA链断裂;2',7'-二氢二氯荧光素(DCFH)法测定细胞内活性氧水平;免疫组化方法测定8-羟脱氧鸟苷(8-OHdG)在细胞内的表达水平;免疫细胞化学法检测细胞内核转录因子NF-κBp65蛋白表达水平。结果大连市4个监测点PM10有机提取物致HepG2细胞DNA链断裂作用存在地点和季节差异;7.5～30μg/mLPM10有机提取物作用HepG2细胞1h后,尾DNA%增大,呈剂量依赖关系。HepG2细胞与7.5～30μg/mL的PM10有机提取物接触1h后,可引起细胞内ROS水平表达的明显增加;7.5～30μg/mL的PM10有机提取物作用于HepG2细胞3h后,细胞内8-OHdG水平的表达增强;HepG2细胞与30μg/mL的PM10有机提取物接触24h后,NF-κBp65蛋白表达水平明显增高。结论PM10有机提取物可引起体外HepG2细胞DNA链断裂;DNA链断裂水平随不同季节和不同监测点而异;PM10引起DNA损伤的机制可能是细胞内ROS生成增多,8-OHdG表达增高及NF-κBp65蛋白表达水平升高而导致的氧化性DNA损伤。Objective To investigate DNA damage induced by inhalable particulate matter （PM10） and its mechanisms in HepG2 cells. Methods DNA strand breaks induced by extractable organic matter of PM10 was assessed by single cell gel electrophoresis （SCGE） assay. Intracellular generation of reactive oxygen species （ ROS ）, expression of 8- hydroxydeoxyguanosine（8-OHdG） and protein expression of NF-KB p65 were estimated by 2, 7-diehlorofluorescein （DCFH） ,immunocytochemistry staining and Western blot,respectively. Results Significant differences in percent of tail DNA induced by the extractable organic matter of PM10 were revealed between samples collected in summer and winter seasons and from different monitoring sites. The percent of tail DNA in HepG2 ceils significantly increased in a dose-dependent manner after exposure to 7.5 - 30μg/mL extractable organic matter of PM10 for liar. After exposure to extractable organic matter of PM10 for lhr,intracellular ROS increased significantly. The 8-OHdG was positive in the HepG2 cells treated with extractable organic matter of PM10. The protein expression of NF-KB p65 significantly increased in HepG2 cells after treatment with 30/xg/mL extractable organic matter of PM10 for 24 hr. Conclusion The extractable organic matter of PM10 induces DNA strand breaks in HepG2 cells. Significant differences in percent of tail DNA relates to PM10 samples collected at different times and locations. The extractable organic matter of PM10 exerts DNA damage effects in HepG2 cells probably through oxidative DNA damage induced by intracellular ROS ,increase of 8-OHdG formation and the expression of NF-KB p65.

关 键 词：PM10 HepG2细胞 DNA链断裂 氧化性DNA损伤 

分 类 号：R994.6[医药卫生—毒理学]