The time-dependent effect of insulin on the expression of SREBP-1,FAS and lipid droplet formation in HKC cells
- VernacularTitle:胰岛素对人肾小管上皮细胞SREBP-1、FAS表达及脂质代谢的时效性研究
- Author:
Jun HAO
;
Shuxia LIU
;
Qingjuan LIU
;
Song ZHAO
;
Shushen ZHENG
;
Fang YAO
;
Wei LIU
;
Huijun DUAN
- Publication Type:Journal Article
- Keywords:
insulin;
HKC cells(human renal proximal tubular epithelial cells line);
SREBP-1(sterol regulatory element binding protein-1);
FAS(fat acid synthase);
lipid droplet formation;
time-dependent effect
- From:
Chinese Pharmacological Bulletin
2010;26(4):517-521
- CountryChina
- Language:Chinese
-
Abstract:
Aim To investigate the time-dependent effect of insulin on the expression of SREBP-1(sterol regulatory element binding protein-1),FAS(fat acid synthase)and lipid droplet formation in HKC cells(human renal proximal tubular epithelial cells line).MethodsHKC cells were respectively treated with 100 nmol·L~(-1) insulin for 0,2,4,6,12 h and 24 h.The analysis of SREBP-1 and FAS mRNA was performed by RT-PCR and the expression of SREBP-1 protein was detected by Western blot and immunocytochemistry.Furthermore,Oil Red O staining was used to determine cellular lipid droplet formation.ResultsCompared with HKC cells of 0 h group,there was no difference of SREBP-1 and FAS mRNA in HKC cells of 2 h group.However,the expression of SREBP-1 and FAS mRNA was significantly increased in HKC cells of 4,6 h and 12 h group.Further,the most expression of SREBP-1 and FAS mRNA was at 6 h group and was respectively increased by 3.578 and 4.272 times compared with 0 h group.The results of Western blot showed that the precursor and mature segments of SREBP-1 protein in 4,6 h and 12 h group HKC cells were increased and those of 6 h group HKC cells were the highest and about 4.106 and 5.167 times than those of 0 h group HKC cells.Immunocytochemistry presented the result that SREBP-1 protein was located in the plasma and the expression of 4,6 h and 12 h group HKC cells was significantly higher than that of 0,2 h and 24 h group HKC cells.The result of Oil Red O staining showed that lipid droplet markedly deposited in 6 h group HKC cells,contrarily,no lipid droplet was found in HKC cells of other groups.ConclusionAbove results suggested that insulin up-regulated SREBP-1 and FAS in time-dependent manner that led to cellular lipid droplet deposit,which may play an important role in the pathogenesis of renal lipid accumulation in metabolism syndrome.
