Expression Of Placenta Growth Factors And Interleuin-6 In Patients With Preeclampsia And Its Relationship

Objective:Preeclampsia (PE) is a hypertensive disorder specific to pregnancy and is a major cause of perinatal maternal and neonatal death and morbidity worldwide, affecting nearly 7%-10% of all pregnancies . As much as 15% to 20% of maternal mortality in developed countries can be attributed to PE. Despite the large number of studies focusing on PE, the etiology of this disease remains to be elucidated. Identification of genetic risk factors and of the populations with high risk of disease, could aid substantially in the attacking of this important public health problem and provide clues for the prevention or treatment of PE. Interleuin-6 (IL-6) and placenta growth factors (PLGF) come from trophoblastic cells contribute to normal placental formation and development. Some investigations presume their abnormal expression participate in the development of PE. By case-control study to detect the expression of IL-6 of amniotic fluid and PLGF of placenta in patients with PE, and analyzing their correlation ,to make an inquiry into the role of amniotic fluid IL-6 and placenta PLGF in development of PE.Methods:60 caesarean delivered parturient (including study group 30 cases, among them 9 mild PE cases, 21 sever PE cases; control group 30 cases, they were performed section caesarean due to other reasons) were studied. Amniotic fluid levels of IL-6 was measured by enzyme linked immunosorbent assay (ELISA) and expression of PLGF in the placenta determined by immuno-histochemistry. To IL-6 and PLGF make Pearson correlation analysis.Results1. IL-6 of amniotic fluid measurement result: Amniotic fluid concentrations of IL-6 in PE group was significantly lower than that of control group(P<0.01);amniotic fluid concentrations of IL-6 in mild PE group had no significant differences with that of control group ( P > 0.05 ) ;amniotic fluid concentrations of IL-6 in server PE group was significantly lower Than that of control group(P<0.001); amniotic fluid concentrations of IL-6 in server PE group was significantly lower Than that of mild PE group(P<0.05).2. PLGF immuno-histochemistry dyeing location result: In PE group, PLGF expressed mainly in the cytoplasm of syncytiotrophoblastic cell, there was little PLGF expression in the endothelial cell of micrangium of villus, the mesenchymal cell of villus and decidual cell of placenta. In control group, PLGF expressed mainly in the cytoplasm of syncytiotrophoblastic cell, in the endothelial cell of micrangium of villus we detected average degree PLGF expression, we also observed little PLGF expression in the mesenchymal cell of villus and decidual cell of placenta. PLGF expression location In PE group had no differences with that of control group, but present weakly positive expression.3. PLGF expression result of syncytiotrophoblastic cell of placenta: The level of PLGF expression in syncytiotrophoblastic cell of placenta in 30 cases of PE group was significantly lower Than that of control group(P<0.001); among them the level of PLGF expression in syncytiotrophoblastic cell of placenta in both mild and server PE group was significantly lower Than that of control group(P<0.001; P<0.001).4. PLGF of placenta and IL-6 of amniotic fluid comparison result: Totality in PE group, levels of PLGF correlate with concentrations of IL-6(r=0.874,P<0.001),among them in server PE group, levels of PLGF correlate with concentrations of IL-6(r=0.874,P<0.001), but in mild PE group, levels of PLGF incorrelate with concentrations of IL-6(r=0.313,P=0.412); In control group, levels of PLGF correlate with concentrations of IL-6(r=0.822,P<0.001).Conclusions1,The decreased levels of IL-6 in the amniotic fluid is associated with the development of PE and correlates with the severity of preeclampsia.2,PLGF is secreted by trophocyte mainly, which plays an important role in the normal placental formation and development.3,The decreased expression of PLGF in the placenta is associated with the development of PE and expression of PLGF correlates with the severity of preeclampsia significantly, more serious PE, less PLGF expression of placenta.4,IL-6 of amniotic fluid can induce trophocyte of placenta to secret PLGF. The decreased levels of IL-6 of amniotic fluid can lead to decreased levels of PLGF. The decreased levels of IL-6 and PLGF might lead to shallow trophoblastic invasion followed by an incomplete remodelling of the maternal vascular structures, leads to uteroplacental insufficiency, ischemia and hypoxia, to accelerate development of PE.