[Changes of matrix metalloproteinase-2 and tissue inhibitor of metalloproteinase-2 expressions on cultured rat mesangial cells transfected with Smad 7 vector].

Objective: To investigate matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) expressions in the cultured rat mesangial cells (MsC) transfected with Smad 7 vector and to elucidate the mechanism of Smad 7 in blocking tissue fibrosis.

Methods: Lipofectin method was used to transfect Smad 7 vector into MsC. Western blot and RT-PCR analyses were then used to detect Smad 7 protein and mRNA expression levels. The expressions of MMP-2 and TIMP-2 were determined by Western blot, RT-PCR and zymography assay.

Results: Two MsC clones (S-22, S-26) with Smad 7 overexpression were successfully established. The two clones showed an increased expression of MMP-2 protein and enhanced enzyme activity. The expressions of TIMP-2 protein and mRNA however were suppressed.

Conclusions: It is possible that Smad 7 can alleviate the development of tissue fibrosis by upregulating the expression of MMP-2 and downregulating the expression of TIMP-2 in mesangial cells.