Effect of TGF-β1 on TGF-β1 gene promoter activity in mouse hepatic satellite cells

Objective:To investigate the effects of TGF-β1 on promoter activity of human transforming growth factor-beta1(TGF-β1) gene.Methods:The fragments with different length of the 5′-end sequence of the human TGF-β1 gene between -1 328 bp to +812 bp were obtained from a healthy male person genomic DNA, and the sequences were fused to chloramphenicol acetyltransferase reporter gene in the pCAT-enhancer plasmid to construct five chimeric recombinant plasmids. These recombinant plasmids were transiently transfected into rat hepatic setellate cell line(nFSC) by FuGENE6 transfection methods. The cells transfected with chimeric recombinant plasmids were cultured on media in the absence or presence of TGF-β1(2 5 ng/ml),CAT activities in transfected cells were tested and compared.Results:The different concentration of TGF-β1 can prevent the proliferation of nFSC, and these effects are dose-dependent; The presence TGF-β1 can stimulate the CAT activity of cells transfected with phTGF0 585?phTGF1 120?phTGF1 423?phTGF1 680?phTGF2 140 up to 2～5 times higher then cells cultured with absence of TGF-β1.Conclusion:The TGF-β1 can stimulate CAT activities in nFSC transfected with phTGF0 585?phTGF1 120?phTGF1 423?phTGF1 680?phTGF2 140. These results suggest that TGF-β1 have an autoregulation effect on TGF-β1 gene.