Smad7抑制TGF-β1对肝星状细胞α1(Ⅲ)前胶原基因表达的促进作用

Smad7 overexpression inhibits TGF-β1-stimulated procollagen α1(Ⅲ) expression in cultured hepatic stellate cells

目的:探讨在加入TGF-β1的条件下,Smad7过度表达对肝星形细胞-T6(HSC-T6)α1(Ⅲ)前胶原mRNA水平的作用.方法:体外培养HSC-T6细胞,分为正常对照组、TGF-β1对照组、空载质粒组、Smad7质粒组、TGF-β1+空载质粒组和TGF-β1+Smad7质粒组.通过Fugene6介导Smad7质粒转染,继续培养48h.采用Realtime-PCR、RT-PCR方法检测Smad7和α1(Ⅲ)前胶原mRNA水平.结果:TGF-β1+Smad7质粒组、Smad7质粒组Smad7 mRNA水平较正常对照组、空载质粒组显著增高(t=59.43、59.41、54.27及54.25,均t>t0.01,均P<0.01).Smad7质粒组α1(Ⅲ)前胶原基因mRNA表达与正常对照组、空载质粒组相比无明显差异(t=1.25与1.27,均t<t0.05,均P>0.05).但TGF-β1+Smad7质粒组α1(Ⅲ)前胶原mRNA水平较TGF-β1+空载质粒组和TGF-β1对照组明显降低(t=103.87与45.70,均t>t0.01,均P<0.01).结论:Smad7可显著抑制TGF-β1对HSC-T6α1(Ⅲ)前胶原mRNA表达的促进作用,而对HSC-T6α1(Ⅲ)前胶原mRNA表达无明显影响.

AIM：To investigate the effects of Smad7 overexpression on transforming growth factor-β1（TGF-β1）-stimulated procollagen α1（Ⅲ） expression in cultured hepatic stellate cells（HSC-T6）.METHODS：Cultured HSC-T6 cells were divided into six groups：normal control group, TGF-β1 group, vehicle plasmid group, Smad7 plasmid group, TGF-β1 plus vehicle plasmid group, and TGF-β1 plus Smad7 plasmid group.Smad7 plasmid and vehicle plasmid were transfected into HSC-T6 cells with FuGENE 6 Reagent.Fortyeight hours after transfection, the expression lev-el of procollagen α1（Ⅲ） mRNA was determined by reverse transcription-polymerase chain reaction（RT-PCR） and real-time RT-PCR.RESULTS：Compared with the normal control group and the vehicle plasmid group, the expression levels of Smad7 mRNA increased significantly in the Smad7 plasmid group and the TGF-β1 plus Smad7 plasmid group（t=59.43, 59.41, 54.27 and 54.25, respectively;all t t 0.01 and all P 0.01）.Although there were no significant differences in the expression levels of procollagen α1（Ⅲ） mRNA between the Smad7 plasmid group and the normal control group or the vehicle plasmid group（t=1.25 and 1.27, respectively;both t t 0.05 and both P 0.05）, the expression level of procollagen α1（Ⅲ） mRNA in the TGF-β1 plus Smad7 plasmid group was significantly lower than those in the TGF-β1 group and the TGF-β1 plus vehicle plasmid group（t =103.8 and 45.7, respectively;both t t 0.01 and both P 0.01）.CONCLUSION：Overexpression of Smad7 inhibits the expression of procollagen α1（Ⅲ） stimulated by exogenous TGF-β1 in cultured hepatic stellate cells.