摘要
目的探讨大气PM2.5对人肝肿瘤细胞株Hep G2细胞脂质堆积的影响及可能的作用机制。方法采集广州城区大气PM2.5,以6.25、12.5、25、50和100μg/ml PM2.5分别染毒Hep G2细胞,采用细胞活性检测试剂盒(CCK-8法)测定细胞存活率,确定PM2.5实验浓度。6.25、12.5、25μg/ml PM2.5染毒细胞36 h后,采用油红O染色观察肝细胞内脂滴变化,测定细胞内甘油三酯和总胆固醇含量,并采用实时荧光定量PCR法检测细胞肝X受体α(liver X receptor alpha,LXRα)和固醇调节元件结合蛋白-1c(sterol regulatory element binding protein-1c,SREBP-1c)的表达情况。结果油红O染色显示,染毒组Hep G2细胞内可见大量红色脂滴,并伴有脂滴融合现象。PM2.5染毒细胞36 h后,各染毒组Hep G2细胞总胆固醇含量高于对照组,但差异无统计学意义(P>0.05);甘油三酯含量高于对照组,且随着PM2.5浓度的增加而升高,差异均有统计学意义(P<0.05或P<0.01)。PM2.5染毒细胞24 h和36 h后,染毒组Hep G2细胞LXRα和SREBP-1c的m RNA表达均高于对照组,差异均有统计学意义(P<0.05或P<0.01)。结论 PM2.5可促进肝细胞脂质堆积,该过程可能与其上调LXRα和SREBP-1c的表达有关。
Objective To investigate the effect of PM2.5 on lipid accumulation in HepG2 cells and its possible pathophysiological mechanisms. Methods The samples of fine particulate matter were collected in Guangzhou and made into suspension with different concentration. The cell viability was detected by Cell Counting Kit-8 and to determine the appropriate test concentration of PM2.5. The accumulated lipid was stained with Oil red O. Commercial kit for the level of triglyceride and total cholesterol were used for determination of lipid content. Real-time PCR was applied to investigate the mRNA expression of liver X receptor alpha （LXRα） and sterol regulatory element binding protein-lc （SREBP-lc）. Results Oil red O staining in HepG2 cells presented large amount of orange-red lipid droplets along with lipid droplet fusion in cytoplasm of HepG2 cells in PM2.5 treated groups, the content of TG in PM2.5 treated groups was significantly increased （P〈0.05,P〈0.01） in a dose- dependent manner; The expression of LXRα and SREBP-lc mRNA levels were significantly up-regulated （P〈0.05,P〈0.01） also. Conclusion PM2.5 may induce lipid accumulation, which may be due to up-regulated expression of LXRα and SREBP- lc mRNA.
出处
《环境与健康杂志》
CAS
北大核心
2015年第6期509-512,F0003,共5页
Journal of Environment and Health
基金
广东省科技计划项目(2012B31800230)
关键词
PM2.5
非酒精性脂肪肝
肝X受体Α
固醇调节元件结合蛋白-1C
PM2.5
Non-alcoholic fatty liver disease
Liver X receptor alpha （LXRα）
Sterol regulatory element binding protein-lc（SREBP-lc）
