Significance Of Placenta-specific MiR-520g In Preeclampsia

Preeclampsia(PE),a complex multi-system pregnancy syndrome,characterized by hypertension and significant proteinuria after 20 th week of pregnancy,is one of the main diseases that harm maternal and newborn health.Early diagnosis/prediction of preeclampsia is urgent in this field.In previous studies,we had measured 11 mi Rs in maternal serum by q RT-PCR,and found in the first trimester mi R-520 g level in PE group was significantly higher than that in the control group.We postulated that mi R-520 g may be involved in the pathophysiology of PE.In the present study,we aimed to explore the varying pattern of mi R-520 g during gestation and the significance of mi R-520 g in PE,tried to clarify the underlying mechanisms.Method: 1.Establish the bank of biological samples for PE,collect the blood samples of pregnant women.2.Detect the serum mi R-520 g concentration by q RT-PCR.3.Observe the location of mi R-520 g on placenta by in situ hybridization(ISH).4.Detect MMP2,VEGFA level in early pregnancy(5-12 weeks)plasma and cell culture supernatant by ELISA.5.Observe the distribution of MMP2,VEGFA,Ephrin B2 and EPHB4 on placenta by immunohistochemistry.6.Using mi R-520 g mimics and inhibitors,establish cell intervention model of HTR8/SVneo and HUt MEC,study the influence of mi R-520 g on two kinds of cell's biological behavior and probable mechahisms,explore the potential role of mi R-520 g in Sp A remodeling.Result: 1.With pregnancy progress,the expression of serum mi R-520 g increased;at first-trimester,mi R-520 g in preeclampsia group was significantly higher than that in the control group,but no significant differences were found in the second and last-trimester.2.At first-trimester,MMP2 in preeclampsia plasma was significantly higher than that in the control group(225.0411±34.21961 VS.203.5094±24.47596ng/ml,p=0.04),while no significant difference was found for plasma VEGFA in two groups(p=0.717).3.Mi R-520 g was found in cytoplasm of placental trophoblasts,no positive signal of mi R-520 g was found in both endothelial cells and mesenchymal cells.4.MMP2 was expressed in the syncytial cell layer;VEGFA expression was detected in trophoblasts,endothelial cells and mesenchymal cells;Ephrin B2 expression was observed in trophoblasts,endothelial cells and mesenchymal cells,predominantly in cytotrophoblasts;Strong expression of EPHB4 in membranes of cytotrophoblast was detected,and weak expression of EPHB4 was observed in syncytiotrophoblasts.5.No significant difference was found for MMP2/VEGFA/Ephrin B2/EPHB4 m RNA expression among the mi R-520 g mimic/inhibitor/control groups.6.The expression of MMP2 and VEGFA in HTR8/SVneo was reduced when treated with mi R-520 g mimic,while the expression of Ephrin B2 and EPHB4 remained unchanged.In HUt MEC,the protein expression of MMP2/VEGFA/Ephrin B2/EPHB4 showed no significant changes with mi R-520 g mimic/inhibitor/control treatment.7.The migration and invasion of HTR8/SVneo were inhibited by mi R-520 g mimic treatment.Mi R-520 g mimic promoted the apoptosis of HTR8/SVneo.Conclusion: 1.Maternal serum mi R-520 g could be potential biomarker for preeclampsia prediction.2.By promoting apoptosis and inhibiting the migration and invasion of trophoblast via MMP2 and VEGFA translation redution,mi R-520 g may play a role in the defective spiral artery remodeling,and thus contribute to preeclampsia pathophysiology.