Mifepristone increases AQP1 mRNA expression, angiogenesis, and cell permeability through the ERK MAPK pathway.

Abstract

The purpose of this study was to investigate the mechanism of mifepristone serves as an anti-implantation contraceptive drug on aquaporins 1 (AQP1) expression. Human umbilical vein endothelial cells (HUVECs) were used to detect the effects of different concentrations of mifepristone (0, 0.065, 0.2, and 1μmol/L) on the activity of angiogenesis and AQP1 expression. The expression of AQP1 was tested by the real-time PCR. The angiogenesis and penetration function of HUVECs was investigated by Matrigel lumen formation and trans-well assay, respectively. The expression of AQP1, angiogenesis and cell permeability were significantly higher than control groups in HUVECs treatment with mifepristone at 1μmol/L for 12h. Estrogen and progesterone decreased the up-regulation of AQP1 and cell permeability, not angiogenesis, induced by mifepristone. Mifepristone increased protein levels of p-ERK, not p-p38 or p-JNK, and pre-treatment with ERK MAPK-specific inhibitor significantly inhibited the up-regulation of AQP1 mRNA expression, angiogenesis and cell permeability induced by mifepristone. si-AQP1 significantly reduced the up-regulation of angiogenesis, cell permeability and p-ERK/ERK ratio expression induced by mifepristone treatment. Overexpression of AQP1 enhanced the increase of expression ratio of p-ERK/ERK induced by mifepristone. Low-dose mifepristone increased cell permeability, angiogenesis and AQP1 expression, which was involved in MAPK pathways. This provides new insights into the molecular mechanism of mifepristone serves as an anti-implantation contraceptive drug.