The Mechanism Of In Vitro Balance Regulation Between VEGF And Its Antagonist SFlt-1

Preeclampsia (PE) is a sever pregnancy complication. According to the global statistics, PE accounts for 14% of pregnancy-related maternal death and 15% of preterm birth. Preeclampsia is that pregnant women developed hypertension, proteinuria, edema after 20 weeks of gestation, and often accompanied by headache, dizziness, vomiting, epigastric discomfort, impaired vision and other symptoms. Because the mechanism of this disease development is still unclear, current treatment is limited to the symptoms related treatment such as for high blood pressure, edema and other symptoms. To date, the only effective cure is deliver the fetus and placenta, which in turn cause preterm birth. Recent, studies shown that VEGF stimulated sFlt-1 production in the trophoblast is one of the cause for PE, however, how VEGF regulates sFtl-1 expression in the trophoblasts is not known.Objective:Using tropholbast cell lines to investigate the signal pathways involved with VEGF up-regulation sFlt-1 in vitro.Materials and methods:Lentivirus expression VEGF 164 and GFP (LV-VEGF-GFP) were produced and used for transfecting JEG3 cells and HTR8/SV neo cells, the the cells were sorted by flow cytometry to obtain stable VEGF overexpression JEG3 cell line (VEGF-GFP-JEG3) and HTR8/SV neo cell line (VEGF-GFP-HTR8). Then, we investigated the sFlt-1 expression changes, migration and invasion functional changes in the VEGF-GFP-JEG3 and VEGF-GFP-HTR8 compared with JEG3 and HTR8/SV neo by adding inhibitors of VEGF receptors:via either inhibited Flt-1 by MK-2461, KDR by ABT869, and both the receptors by XL-184.Results:We found that the mRNA level and protein level of sFlt-1 in VEGF-GFP-JEG3 cells are all decreased significantly when the cells treated by MK-2461, ABT-869 and XL-184. And the migration of these three groups of cells infiltration capacity significantly increased. Interestingly, the mRNA level of VEGF-A, sFlt-1, Flt-1, and KDR in VEGF-GFP-HTR8 cells are all increased significantly when the cells after the treatment of MK-2461, ABT-869 and XL-184. But the protein level of sFlt-1 turned out decreased significantly. In addition, the migration of these three groups of cells infiltration capacity significantly increased.Conclusion:Up-regulation of sFlt-1 induced by over-expression of VEGF may through the VEGF/Flt-1 signaling pathways and the VEGF/KDR signaling pathway, which needs further study to make sure who plays a major role.