大气细颗粒物对HepG2细胞氧化应激的影响

Effect of atmospheric fine particulate matter on oxidative stress of HepG2 cells

目的 探讨大气细颗粒物(PM2.5)对肝HepG2细胞氧化应激的影响。方法 采集广州市区大气中的PM2.5干预肝HepG2细胞,分别设立PM2.5不同浓度组(12.5μg/mL组、25μg/mL组和50μg/mL组)和阴性对照组。采用DCFH-DA荧光探针法检测各组细胞内氧自由基(ROS)水平;采用分光光度试剂盒检测细胞内超氧化物歧化酶(SOD)及丙二醛(MDA)的含量;采用实时荧光定量PCR法测定SOD1、SOD2和CAT的mRNA表达水平。结果 与阴性对照组比较,PM2.5显著上调HepG2细胞内ROS和MDA的含量(P<0.01),显著下调细胞内SOD含量(P<0.01),同时细胞内抗氧化酶相关基因SOD1、SOD2、CAT的mRNA表达明显下降(P<0.05)。结论 PM2.5可诱发HepG2细胞氧化应激,这可能是PM2.5引起非酒精性脂肪肝病的重要机制。

Objective To investigate the effect of atmospheric fine particulate matter(PM2.5) on oxidative stress of HepG2 cells. Methods The samples of PM2.5 were collected from the urban area of Guangzhou and made into suspension. HepG2 cells were divided into the negative control group and three concentrations(12.5, 25 and 50 μg/mL) of PM2.5 treated groups. The levels of intracellular oxygen free radicals(ROS) were detected by DCFH-DA fluorescence probe. The contents of superoxide dismutase(SOD) and malondialdehyde(MDA) in cells were detected by spectrophotometry kit. The mRNA levels of SOD1, SOD2 and catalase(CAT) were measured by realtime fluorescence quantitative PCR. Results Compared with the negative control group, PM2.5 significantly upregulated the contents of ROS and MDA in HepG2 cells(P<0.01), downregulated the content of SOD(P<0.01)and decreased the mRNA expression of intracellular antioxidant enzyme related genes SOD1, SOD2 and CAT(P<0.05). Conclusion PM2.5 can induce oxidative stress in HepG2 cells, which may be one of the mechanisms related to the development of nonalcoholic fatty liver disease caused by PM2.5.