摘要: |
目的 利用毒胡萝卜素诱导肝细胞内质网应激模型,观察在内质网应激状态下肝细胞脂肪沉积情况,并初步探讨其分子机制。方法 以人L02、HepG2肝细胞株为研究靶细胞,将两种细胞均分为正常对照组和实验组(培养液内含毒胡萝卜素1 μmol/L),采用三酰甘油(TG)试剂盒、油红O染色检测肝细胞脂肪沉积情况,实时荧光定量PCR法检测SREBP-1c、LXRs的mRNA表达情况,蛋白质印迹法检测GRP78、SREBP-1c、LXRs的蛋白表达情况。结果 蛋白质印迹结果显示,实验组GRP78的表达较对照组升高(P<0.05),表明肝细胞内质网应激模型建立成功。在内质网应激状态下,毒胡萝卜素作用48 h后实验组L02与HepG2细胞脂肪沉积均较对照组增加(P<0.01)。与对照组相比,实验组L02和HepG2细胞SREBP-1c在基因水平和蛋白水平表达均升高(P<0.05),而LXRs在基因水平和蛋白水平的表达均无变化。结论 内质网应激可能通过上调SREBP-1c诱导肝细胞脂肪沉积,而LXRs未参与该过程。 |
关键词: 内质网应激 肝细胞 脂肪沉积 固醇调节元件结合蛋白1c 肝X受体 |
DOI:10.3724/SP.J.1008.2012.001055 |
投稿时间:2012-07-09修订日期:2012-09-06 |
基金项目:国家自然科学基金青年科学基金(81000357). |
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Endoplasmic reticulum stress-induced fatty depositon in hepatocytes and the possible mechanism |
WAN Ying,FANG Dian-liang,SHEN Wei*,NING Bo* |
(Department of Gastroenterology, Second Affiliated Hospital, Chongqing Medical University, Chongqing 400010, China *Corresponding authors.) |
Abstract: |
ObjectiveTo observe the fatty deposition in thapsigargin-induced endoplasmic reticulum stress model in hepatocytes and to discuss the possible mechanism. MethodsHepatocytes (L02 cell and HepG2 cell line ) were divided into control group and experimental group (treated with 1 μmol/L thapsigargin). Fatty deposition in the hepatocytes was observed by biochemical assay and oil red O staining. Real-time PCR was used to test the expression of SREBP-1c and LXRs mRNA. And Western blotting analysis was used to examine the expression of protein of GRP78,SREBP-1c and LXRs. ResultsWestern blotting analysis showed that GRP78 protein expression in the experimental group was remarkably higher than that in the control group (P<0.05 ), indicating the successful establishment of the endoplasmic reticulum stress model in hepatocytes. The hepatocyte fatty deposition in the experimental group was significantly more than that in the control group 48 h after thapsigargin exposure(P<0.01). The expression of SREBP-1c mRNA and protein in the experimental group was significantly higher than that in the control group (P<0.05 ), and the expression of LXRs mRNA and protein was not significantly between the two groups. ConclusionEndoplasmic reticulum stress may induce hepatocyte fatty deposition throuth up-regulating SREBP-1c, and LXRs is not involved in the process. |
Key words: endoplasmic reticulum stress hepatocytes fatty deposition sterol regulatory element binding protein 1c liver X receptors |