DNA聚合酶β表达水平对苯代谢物氢醌致细胞凋亡及线粒体膜电位的影响  

Effect of DNA polymerase beta on apoptosis and mitochondrial membrane potential induced by hydroquinone,a metabolite of benzene

作　　者：陈晨[1] 杨沫[1] 张遵真[1] 吴媚[1] 邓雯文[1] 

机构地区：[1]四川大学华西公共卫生学院环境卫生教研室,成都610041

出　　处：《中华劳动卫生职业病杂志》2011年第12期925-929,共5页Chinese Journal of Industrial Hygiene and Occupational Diseases

基　　金：国家自然科学基金资助项目（30872079,81172632）

摘　　要：目的探讨DNA聚合酶β（DNA polymemsebeta，polβ）对氢醌（HQ）所致细胞凋亡的影响及其可能的分子机制。方法以polβ野生型（polβ＋/＋）、polβ缺陷型（polβ-／-）及polβ高表达型（polpoe）小鼠胚胎成纤维细胞为研究对象，以不同浓度的HQ溶液染毒后，采用流式细胞术分别检测HQ对细胞凋亡和线粒体膜电位（△ψm）的影响，试剂盒法测定细胞内活性氧（ROS）和羟自由基（·OH）含量；化学发光法分析细胞内超氧化物歧化酶（SOD）和谷胱甘肽过氧化物酶（GSH—PX）活力。结果与对照组相比，各染毒组凋亡细胞率和△ψm降低的细胞比例明显增加，差异均有统计学意义（P〈0．05）。与polβ＋/＋细胞比较，20．00、40．00、80．00μmol／L染毒组polβ-／-细胞凋亡率明显增高，10．00、20．00、40．00、80．00μmol/L染毒组polβ oe细胞凋亡率明显降低，差异均有统计学意义（P（0．05）。与polβ＋／＋细胞（20．60％±0．57％、37．95％±0．64％、44．50％±1．27％、57．55％±1．06％）比较，10．00、20．00、40．00、80．00μmol／L染毒组polβ-／-细胞△ψm降低的细胞比例（33．60％±1．55％、46．05％±1．77％、52．75％±2．05％、75．20％±0．56％）明显增高，polβ oe细胞△ψm降低的细胞比例（16．05％±1．20％、29．80％±1．21％、35．15％±1．06％、53．80％±0．85％）明显降低，差异均有统计学意义（P〈0．05）。与polβ＋/＋细胞比较，各染毒组polβ-/-细胞产生的荧光强度明显增高，polβ oe细胞的荧光强度明显降低，差异均有统计学意义（P〈0．05）。与pol β ＋/＋细胞相比，20．00、40．00μmol／L染毒组pol β-／-细胞内·0H含量明显增高，polβ oe细胞内·0H含量明显降低，差异有统计学意义（P〈0．05）。在相同浓度HQ染毒剂量下，polβ-／-细胞内SOD和GSH-Px消耗最快，polβ oe细胞内的SOD和GSH-Px消耗�Objective To explore the effect and mechanism of DNA polymerase β expression level on cell apoptosis and mitochondrial membrane potential induced by hydroquinone. Methods Polβ wild-type cells （polβ ＋/＋）, polβ overexpressed cells （polβ oe） and polβ null cells （polβ -/-） were applied as a model cell system, The effect of cell apoptosis and mitochondrial membrane potential induced by different doses of hydroquinone were analyzed by flow cytometry. The ROS and · OH assay kit were used to examine the cellular ROS and · OH level. The activity of cellular SOD and GSH-Px were tested by Chemiluminescence method after ex- posed to different concentrations of hydroquinone. Results With the dose of hydroquinone increased, the rate of apoptosis and falling of mitochondrial membrane potential （Aψm） in cells were increased compared with the control. When compared with polβ ＋/＋ cells, the rate of apoptosis in polβ -/- cells exposed to 20.00, 40.00, 80.00 p.mol/L hydroquinone increased and the rate of apoptosis in polβ oe cells exposed to 10.00, 20.00, 40.00, 80.00 μmol/L hydroquinone decreased （P〈0.05）. Compared with polβ ＋/＋ cells （20.60%±0.57%, 37.95%±0.64%, 44.50%±1.27%, 57.55%±1.06% ）, the rate of cell which undergone mitochondrial depolarization in polβ -/- cells treated with 10.00, 20.00, 40.00, 80.00 μmol/L hydroquinone （33.60%±1.55%, 46.05%±1.77%, 52.75%±2.05%, 75.20%±0.56%） increased. The rate of cell which undergone mitochondrial depolarization in polβ oe cells exposed to 10.00, 20.00, 40.00, 80.00 μmol/L hydroquinone （16.05%±1.20%, 29.80%±1.21%, 35.15%± 1.06%, 53.80%±0.85%） decreased （P〈0.05）. When compared with polβ ＋/＋ ceils, fluorescent intensity of polβ -/- cells treated with different dosages of hydroquinone increased, while which of polβ oe cells decreased （P〈0.05）. Compared with polβ ＋/＋ cells, ·OH level of polβ -/- cells treated with 20.00, 40.00 μmol/L hydroquinone significantly enhanced, while which of pol

关 键 词：DNA聚合酶Β 氢醌类 膜电位 过氧化物酶类 

分 类 号：R114[医药卫生—卫生毒理学]