硒和砷对HepG2细胞氧化应激和DNA氧化损伤及修复的作用  

Effect of selenium and arsenic on oxidative stress,DNA oxidative damage and repair in HepG2 Cells

作　　者：来瑞平[1] 王艺陪[1] 李晓暖[1] 余日安[1,2] 杨成峰[1] 鲁文清[1] 

机构地区：[1]华中科技大学同济医学院公共卫生学院劳动卫生与环境卫生学系,教育部环境与健康重点实验室,武汉430030 [2]广东药学院公共卫生学院劳动卫生与环境卫生学系

出　　处：《卫生研究》2008年第6期645-648,共4页Journal of Hygiene Research

基　　金：国家自然科学基金资助项目(No.30471500)

摘　　要：目的研究硒和砷单独及联合作用对HepG2细胞氧化应激和DNA氧化损伤及修复的影响。方法采用不同浓度的硒(2.5、5.0和10.0μmol/L亚硒酸钠)和砷(1.56、3.13、6.25、12.5和25.0μmol/L亚砷酸)为受试物单独或联合处理HepG2细胞。荧光法测定丙二醛(MDA)作为氧化应激的指标,高效液相色谱-电化学检测法(HPLC-EC)测定8-羟基鸟苷(8-OHdG)作为DNA氧化损伤的指标,Western Blot检测hOGG1表达作为DNA氧化损伤修复的指标。结果在硒和砷单独作用的条件下,可观察到:(1)5.0、10.0μmol/L的亚硒酸钠和6.25、12.5、25.0μmol/L的亚砷酸均引起HepG2细胞MDA含量增加、8-OHdG生成增多、hOGG1表达明显下降(P<0.05,P<0.01);(2)较低浓度的亚硒酸钠(2.5μmol/L)具有有限的抑制8-OHdG生成的作用(P>0.05)。在硒和砷联合作用的条件下,可观察到:(1)2.5μmol/L的亚硒酸钠和6.25μmol/L的亚砷酸同时染毒使MDA含量和8-OHdG的生成均较相应砷剂量组下降(P<0.05);(2)2.5μmol/L的亚硒酸钠与6.25、12.5和25.0μmol/L的亚砷酸同时染毒,hOGG1表达与相应砷剂量组比较没有明显差异(P>0.05)。结论5.0、10.0μmol/L的亚硒酸钠和6.25、12.5、25.0μmol/L的亚砷酸均可引起HepG2细胞氧化应激增强、8-OHdG生成增多、hOGG1表达明显下降;一定剂量的硒(2.5μmol/L的亚硒酸钠)对砷诱导的HepG2细胞氧化应激和DNA氧化损伤具有抑制作用,但对砷所致的DNA氧化损伤修复不产生明显影响。Objective To study alone and combined effect of selenium and arsenic on oxidative stress, DNA oxidative damage and repair. Methods HepG2 cells were treated with selenium （2.5, 5.0 and 10.0μmol/L sodium selenite） alone, arsenic （1.56, 3.13, 6.25, 12.5 and 25.0 μmol/L arsenious acid） alone and combined selenium plus arsenic. The quantitative analysis of malondialdehyde （MDA）, 8-OHdG and hOGG1 was carried out by fluorometric method, HPLC-EC and Western Blot to represent oxidative stress, DNA oxidative damage and repair, respectively. Results Under the condition of alone treatment, sodium selenite （5.0 and 10.0μmol/L） as well as arsenious acid （6.25, 12.5 and 25.0μmol/L） resulted in significant increased levels of MDA and 8-OHdG, and inhibition of hOGG1 expression in HepG2 cells compared with solvent control （P 〈 0.05, P 〈 0.01）. Sodium selenite at the relative low dose （2.5μmol/L） displayed certain anti-oxidative ability （ P 〉 0.05 ）. Combined treatment of sodium selenite （2.5ttmol/L） and arsenious acid （6.25μmol/L） caused significant lower levels of MDA and 8-OHdG than those of correspondent arsenic alone treatment （P 〈 0.05）. hOGG1 expression showed no difference between combined treatment （2.5μmol/L of selenium selenite plus 6.25, 12.5 and 25.0μmol/L of arsenious acid, respectively） and correspondent arsenic alone treatment （P 〉 0.05）. Conclusion Sodium selenite at the concentrations of 5.0, 10.0μmol/L and arsenious acid at the concentrations of 6.25, 12.5, 25.0μmol/L induced enhanced oxidative stress and 8-OHdG production, and inhibition of hOGG1 expression, respectively. Selenium at certain concentration （2.5/μmol/L of selenium selenite） has ameliorative effects on oxidative stress and DNA oxidative damage induced by arsenic, but no effect on repair of DNA oxidative damage.

关 键 词：硒 丙二醛 8-羟基鸟苷 HOGG1 基因表达 氧化损伤 砷中毒 

分 类 号：R994.6[医药卫生—毒理学] Q581[医药卫生—药学]