Expression of matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinase (TIMP), and transforming growth factor-β1 (TGF-β1) in human placenta during preeclampsia

Abstract

Summary Matrix metalloproteinase-2, -9 (MMP-2, -9) and tissue inhibitor of metalloproteinase-1, -2 (TIMP-1, -2) possibly play important roles in the invastion of trophoblast. We noted that the abnormal shallow invasion of trophoblast observed in preeclampsia may be associated with the alteration of MMP, TIMP and its regulator for secretion. Expression of MMP-2, MMP-9, TIMP-2 and TGF-β1 in preeclampsia and normal pregnancy was examined by EIA, zymographic analysis and immunohischemistry. TIMP-1 levels in serum, placental bed and placenta in preelampsia cases were significantly elevated. TGF-β1 levels in both plasma and placental bed were higher in preeclampsia. Zymographic analysis of EIA showed increased secretion of MMP-9 in preeclampsia. TIMP-1 immunostaining in trophoblast cells invading into preeclamptic placental bed tissues was much more prominent than normal trophoblast cells. These data suggested that the increased expressions of TIMP-1 and TGF-β1 may inhibit the invasion of trophoblast into the decidua and myometrium, which is closely associated with preeclampsia.