Modulation of matrix metalloproteinase and TIMP-1 expression by TGF-β1 in cultured human RPE cells

In order to investigate the effects of TGF-β1 on the expression of MMP-2, −9 and TIMP-1 in human retinal pigment epithelial (RPE) cells, the third-sixth passage cultured RPE cells were treated with TGF-β1 at different concentrations (0. 01, 0. 1, 1. 0, 10 ng/mL), the expression of MMP-2, −9 and TIMP-1 mRNA was detected by semi-quantitative RT-PCR assays. MMP-2, −9 and TIMP-1 mRNA were expressed in the cultured RPE cells. The values of MMP-2/β-actin in the cells treated with 0. 1, 1. 0, 10 ng/mL TGF-β1 were 1.04±0.04, 1.07±0.02 and 1.11±0.03, respectively, significantly higher than in the control group (0.96±0.03,P 0.05). It was concluded that TGF-β1 might play an important role in the up-regulation of the expression of MMP-2 in RPE cells and result in a directional shift in the balance between MMP and TIMP. This may be facilitated for RPE cells to migrate in the pathogenesis of vitreoretinopathy.