The up-regulation mechanism of membrane type Ⅰ matrix metalloproteinase （MTI-MMP） in macrophages stimulated by silica in vitro and the contribution of early growth response 1 （Egr-1） transcription factor in the g...The up-regulation mechanism of membrane type Ⅰ matrix metalloproteinase （MTI-MMP） in macrophages stimulated by silica in vitro and the contribution of early growth response 1 （Egr-1） transcription factor in the gene expression pathway were investigated. Macrophages stimulated by silica were treated with Egr-1 antibody or Egr-1 decoy oligodeoxynucleotides （ODN）. The levels of MT1-MMP proteins were determined by Western blot and the expression of MT1-MMP mRNAs was detected by RT-PCR. The results showed as compared with control macrophages, silica-stimulated group showed up-regulated gene expression of MT1-MMP via Egr-1 （P〈0.01）. Compared with silica-stimulated macrophages untreated with antibody, the cells treated with 5 μg/mL Egr-1 antibody were associated with reduced expression of MTI-MMP protein （P〈0.01） and mRNA （P〈0.01）. Compared with silica-stimulated untransfected group, the Egr-1 ＂decoy＂ ODN group was associated with reduction in the expression of MT1-MMP protein and mRNA （P〈0.01）. It was concluded gene expression of MT1-MMP which may play a critical role in silicosis was up-regulated by silica in macrophages. Egr-1 participated in the expression of MT1-MMP and positively regulated the expression. Both Egr-1 antibody and Egr-1 decoy ODN suppressed the expression of MTI-MMP through the Egr-1 pathway and may become a potential therapeutic tool in the management of silicosis in the future.展开更多
文摘The up-regulation mechanism of membrane type Ⅰ matrix metalloproteinase （MTI-MMP） in macrophages stimulated by silica in vitro and the contribution of early growth response 1 （Egr-1） transcription factor in the gene expression pathway were investigated. Macrophages stimulated by silica were treated with Egr-1 antibody or Egr-1 decoy oligodeoxynucleotides （ODN）. The levels of MT1-MMP proteins were determined by Western blot and the expression of MT1-MMP mRNAs was detected by RT-PCR. The results showed as compared with control macrophages, silica-stimulated group showed up-regulated gene expression of MT1-MMP via Egr-1 （P〈0.01）. Compared with silica-stimulated macrophages untreated with antibody, the cells treated with 5 μg/mL Egr-1 antibody were associated with reduced expression of MTI-MMP protein （P〈0.01） and mRNA （P〈0.01）. Compared with silica-stimulated untransfected group, the Egr-1 ＂decoy＂ ODN group was associated with reduction in the expression of MT1-MMP protein and mRNA （P〈0.01）. It was concluded gene expression of MT1-MMP which may play a critical role in silicosis was up-regulated by silica in macrophages. Egr-1 participated in the expression of MT1-MMP and positively regulated the expression. Both Egr-1 antibody and Egr-1 decoy ODN suppressed the expression of MTI-MMP through the Egr-1 pathway and may become a potential therapeutic tool in the management of silicosis in the future.
