[Differences between the expression of matrix metalloproteinase-2, 9 in preeclampsia and normal placental tissues]

To study the possible relationships between expression of matrix metalloproteinase (MMP) 2, 9 and the pathogenesis of preeclampsia in which trophoblast invasion is impaired.

MMP-2, 9 expression were detected by immunohistochemistry streptavidin-biotin complex (SABC) method in 20 normal term placentae and 20 preeclampsia placentae, respectively. In addition, mRNAs for MMP-2, 9 were analyzed by real time PCR in both groups.

The intensities of both MMP-2 and MMP-9 immunostaining in preeclampsia placentae were significantly declined compared to those of normal term placentae (P < 0.05). By using 2(-DeltaDeltaCt) as a relatively quantitative assay, mRNA expression of MMP-2 was significantly higher in 10 normal placentae than those in 13 preeclampsia placentae (7.6 +/- 2.8 vs 5.6 +/- 1.5, P < 0.05). Expression of MMP-9 mRNA was also significantly higher in normal placentae than those in preeclampsia placentae (2.2 +/- 2.6 vs -0.9 +/- 2.0, P < 0.05). Whereas, mRNA expression of MMP-2 was higher compared to MMP-9 in normal term placentae (P < 0.05).

The decreased expression of MMP-2 and MMP-9 in preeclampsia placentae may lead to impaired invasion of trophoblast cells, causing abnormal placentation and occurrence of preeclampsia.