高糖、胰岛素对大鼠肝星状细胞TGF-β1、TIMP-1mRNA表达的影响

Effects of high glucose and insulin on the mRNA expressions of TGF-β1 , and TIMP-1 of hepatic stellate cells in rat

目的 观察高糖和胰岛素对大鼠肝星状细胞（HSC）转化生长因子β1（TGF-β1）、金属蛋白酶组织抑制因子1（TIMP-1） mRNA表达的影响,以探讨糖尿病性肝纤维化的发生机制.方法 将体外培养的大鼠HSC株分别以不同浓度葡萄糖以及不同浓度葡萄糖加胰岛素干预72 h,以甘露醇作为高渗透压对照.采用实时荧光定量PCR技术（RT-FQ-PCR）测定各组HSC TGF-β1、TIMP-1的mRNA表达.结果 各组细胞均有TGF-β1 mRNA、TIMP-1 mRNA表达,各组间TGF-β1 mRNA、TIMP-1 mRNA水平比较差异无统计学意义（P＞0.05）.但在总体趋势上,加胰岛素糖组TGF-β1 mRNA值降低,TIMP-1 mRNA值升高.结论 单纯的高糖不诱导HSC TGF-β1、TIMP-1的mRNA表达量增加,高胰岛素可能诱导HSC TIMP-1分泌增多,TGF-β1分泌减少,糖尿病相关性肝纤维化发生的主要机制可能非TGF-β1途径,但与TIMP-1途径有很大关联.

Objective To explore the mechanism of diabetic hepatic fibrosis by observing effects of high glucose and insulin on expressions of transforming growth factor beta 1 （TGF-β1） and tissue inhibitor of metalloproteinase （TIMP-1） mRNAs of hepatic stellate cell （HSC） in rat.Methods Hepatic stellate cell lines in vitro were administrated by different dose of glucose without insulin and glucose with insulin for 72 h,and mannitol was chosen as hyperosmosis control group.Real time fluorescent quantitation polymerase chain reaction （RT-FQ-PCR） was used to determine expressions of TGF-β1 and TIMP-1 mRNAs of HSC in each group.Results Expressions of TGF-β1 and TIMP-1 mRNAs of HSC in each group could be detected and showed no significant difference among groups （P 〉 0.05）.However,in general,expression of TGF-β1 mRNA in glucose with insulin group decreased and TIMP-1 mRNA increased.Conclusions The mRNA expressions of TGF-β1 and TIMP-1 in HSC could not be induced by high glucose alone,high dose of insulin may increase expressions of HSC TIMP-1 and reduce TGF-β1 expression.The main mechanisms of diabetic hepatic fibrosis may not be TGF-β1 pathway but be closely related to TIMP-1 pathway.