Cinical Analysisof Fetal Death In Therelated Factor And Exploration Of Maternal-fetal Interface In Angiogenesis

[Background]Fetal death means that the fetus has been died before pregnancy product completely ruled out from the mother, and the fetal death after20weeks is usually called stillbirth.[1]. World Health Organization (WHO) has defined the fetal death as without breathing or any other vital signs, such as heartbeat, umbilical cord pulsation, or definite random muscle movement. The fetal mortality rate during pregnancy is about15%-20%, while it is about1%in the fetal death rate after20weeks of pregnancy. As the development of obstetric cesarean technology, the incidence of death decreased significantly, and perinatal death has not been a corresponding decline in fetal death. It may occur at any stage of pregnancy. including in the production process. Fetal death is one of the most serious obstetric complications, and there exist a lot of causes for its occurrence, such as chromosomal abnormalities, infections, pre-eclampsia, placenta, umbilical cord, diabetes and fetal growth restriction. Fetal loss is undoubtedly a bitter blow to their birth parents, so how to prevent fetal death is a severe test for obstetricians and gynecologists. At the same time, perinatal mortality rate is also a measure of an important indicator of a national and regional economic and medical standards.The endothelial cells of a human body is considered to be the largest autocrine, paracrine and endocrine organ, which weighs about1.5kg, it is considered to be a major regulator of vascular tone, platelet activation, monocyte adhesion, thrombosis, inflammation, lipidmetabolism and vascular remodeling. The human endothelial cells is considered to be the largest autocrine, paracrine and endocrine organ, weighing about1.5kg [2], this organ is a major regulator of vascular tone, platelet activation, monocyte adhesion, thrombosis,inflammation, lipid metabolism and vascular remodeling. A major function of the vascular endothelial cell is proliferation and the formation of the capillary network, and it is the formation process of angiogenesis.It is usually supervised by vascular endothelial growth factor, and the angiopoietin (ANGs). It is critical to the balance between vascular factors and anti-angiogenic factor for pregnancy testing in pregnant women stillbirth. These factors contribute to find the causes of the stillbirth. The formation of blood vessels from pre-existing process of neovascularization is regulated by a variety of growth factors and their receptors.The factors regulates pregnancy angiogenesis includes:vascular endothelial growth factor (VEGF), placental growth factor (PIGF), ANGs and human chorionic gonadotropin (HCG)[3] Among these factors, the formation of VEGF-A in angiogenesis plays an important role, commonly referred to as VEGF is VEGF-A, in the stimulation of cell proliferation and induction of esndothelial cell migration, split to play a variety of roles. Angiogenic factors and anti-angiogenic factors have an important role in the regulation of the generation of normal and abnormal blood vessels.The First step of forming the angiogenesis destructing the vascular basement membrane of the vascular endothelial, leading to the cell division and chemokines mobile, resulting in the generation of vascular buds. In the end, the chamber was formed in the blood vessels under the impact of blood flow. The interactions between these factors lead to the formation of blood vessels. Nowadays, angiogenic factors VEGF, PIGF and anti-angiogenic factor of sVEGFR-1of sEng arose much attenations.The PIGF mainly existed in the placenta, heart and lungs. PIGF is a glycoprotein homodimer belonging to the VEGF subfamily [4],with two forms of PIGF-1and PIGF-2.The PIGF-2and VEGF as a synthetic domain of heparin, is a potent angiogenic factor, PIGF homodimers and VEGF receptor interaction does not have a kinase domain.The PIGF by trophoblastic synthesis, placenta express the rich, by the placenta and placental expression of vascular endothelial growth factor receptor-1(Flt-1) in situ extravillous trophoblast cells. PIGF shows lowest during early pregnancy, rises greatly during middle pregnancy, and reaches its peaked during late pregnancy.The PIGF changes and changes of oxygen supply of the placenta during pregnancy is the same. Placental is grown in the relatively hypoxic environment, while in the second trimester, with increasing maternal blood flow, oxygen partial pressure relative increase in PIGF, and PIGF exists obvious differences in the response to hypoxia.In addition, PIGF has strong blood vessel formation characteristics, PIGF promote trophoblast invasion and division through autocrine and paracrine manner, which induced the formation of blood vessels within the vascular bed of the placenta and uterine enlargement [5];When PIGF decreased production, the factor biological activity weakened, and the nourished cells can not invade the endometrial layer, the superficial placenta implantation and vascular remodeling disorder aggravated, causing placenta ischemia and hypoxia, leading to a vicious cycle. It may led to a series of pregnancy, the occurrence of the disease.Thus, PIGF plays an important role in the formation of blood vessels of the placental chorionic In addition, PIGF can control inflammation, so as to achieve the role of anti-inflammatory therapy. VEGFR-1is one of the receptors of VEGF. VEGF will be underwent auto phosphorylation through the induction of this receptor, and activate the signal transduction pathway, which play a biological role. But for the accurate function of VEGFR-1. it is still under dispute.However. VEGFR-1(fIt1) exists in two forms due to alternative splicing, namely membrane type VEGFR-1and soluble forms of VEGFR-1. Soluble form (sVEGFR-1) lack of transmembrane domain and cytoplasmic domain, but it retained the VEGF binding regions [5]sVEGFR-1released into the maternal circulation, confined the angiogenic factors PIGF and VEGF, and hinder their activity through the plasma membrane in the form of the receptor. Another anti-angiogenic factors is Endoglin, also named CD105, is a co-receptor of transforming growth factor TGF-β1and TGF-β3.Its encoding gene is located at chromosome9q32. It has the characteristics of angiogenesis, is also as an important marker of tumor angiogenesis, and has an important relationship with the vascular disease. It is mainly expressed in proliferative endothelial cells, vascular smooth muscle cells, placental fit trophoblast and endometrial stromal cells.While the sEndoglin is in a soluble form Endoglin, some researches have shown that when it is combined with the TGFB1,will become an obstacle of combing the TGFB1and its receptor TGFBR, blocking the activity of nitric oxide synthase-mediated, caused oxide synthesis reducing, resulting an increase in blood pressure and thrombosis, further causing an obstacle maternal hypoxia and insufficient supply of nutrients, which can lead to neovascularization.Endometrium, decidua and placenta is rich in angiogenic forming factors. Generally, the process of angiogenesis factor is combined by bFGF, VEGF or placenta growth factor. The tyrosine kinase system is regulate through a complex signaling mechanisms. When one of a system is blocked, it will cause angiogenesis disorders, and eventually cause the occurrence of pathological pregnancy. This study expects to detect the changes of angiogenesis factor PIGF,anti-angiogenic factor sVEGFR-1,sEng in maternal blood and amniotic fluid, so as to study its relationship with the stillbirth.[Objective]This paper mainly studies the factors lead to fetal death in recent years, and further analyze the possible reasons lead to fetal death. From the analysis of angiogenic factors and anti-angiogenic factor changes in fetal death in the pregnant women amniotic fluid and maternal blood, we discuss its relationship with stillbirth, and thus open up new ideas for the etiology and pathogenesis of stillbirth and placental pathologic factors.[Materials and methods]All of the material sources were retrospectively analyzed from the stillbirth patient birth in Maternal and Child Health Hospital of Shenzhen from2009to2012, and we chose40cases of pregnant women in it from the Maternal and Child Health Hospital of Shenzhen between March2012-Septembe2012. In the experiments, we selected20cases of childbirth for the experiment group, while another20cases during the same period unplanned pregnancy for comparison. There was no statistically significant difference (P>0.05) of maternal age, gestational age, maternal time in the groups.. All of the pregnant women are single births, and in all cases, they had no high blood heart kidney disease, diabetes and hyperthyroidism history, all pregnant women had no history of blood transfusion and the history of immunotherapy.[Experiment methods]1. All Subjects were caught the line amniocentesis amniotic fluid, and taken the into the BD canal, immediately centrifuged for10minutes at4℃with a speed of3000rpm. Then placed at-80°efrigerator for preparing.2. We took the double-antibody sandwich enzyme-linked immunosorbent assay (ELISA)method to test the assay of maternal serum of sVEGFR-1and sEng level, and read the OD value. According to the standard OD value to map out the standard curve, then we detect each studyconcentration values corresponding to the standard curve.3. Immunohistochemistry:after the maternal placenta delivery, we took a organization of the maternal side of the placenta with the size of1.0X1.0X1.0, fixed by4%para-formaldehyde for24hours, embedded in paraffin, and cut4um thick serial sections for placental morphologic observation.4. Data was analyzed by the SPASS13.0statistical software,the statistical data were tested of normality and homogeneity of variance. If the variance is homogeneity,we use2independent T samples for the test, while suppose the variances are unequal, we use2independent samplesnon-parametric for the tests. These two both were caught based on a=0.05for the significant level of inspection, only the data P<0.05can be used for the statistion.[Results]1. From2009to2011, there are a total of45,332cases of childbirth in our hospital, including560cases of,perinatal death. Except deformed children and congenital folly child deaths, there are140cases of stillbirths, accounting for0.30%of the total number of childbirth. 2. The amniotic fluid sVEGFR-1and sEng in the experimental groups are significantly higher than those in the comparison group.[sVEHGR-1:10903.78pg/ml (P25:10150.77, P75:11847.75) pg/ml VS8063.82pg/ml (P25:5745.70, P75:10613.80) pg/ml; sEng:765.16pg/ml (P25:320,P75:1032.14) pg/ml VS191.86pg/ml (P25:80.5, P75:245.35) pg/ml], amniotic fluid in the experiment group:PIGF is500.61pg/ml (P25:121.74, P75:804.255) pg/ml, control group:1015.40pg/ml (P25:262.06,P75:1776.81) pg/ml。3. The expression of Endoglin in the experiment group is higher than that in the control group(experiment group about42.5±8.80, control group about13.97±4.78, P<0.05); The expression of VEGFR-1in the experiment group is higher than that in the control group(experiment group about44.50±8.80, control group about14.63±3.60, P<0.05).[Conclusion]1. Usually, the umbilical cord was a major reason for the stillbirth, and the umbilical cord torsion is more common among it. So we should take active measures by detecting the Prenatal color Doppler and umbilical blood flow velocity. For the fetus with cord entanglement for multi-week, we should take enough attention and strengthen the fetal monitoring. What is more, pregnancy should be enhanced prenatal screening and ultrasound screening to detect the abnormal factors and take a treatment in time. It is expected to enhance the level of prenatal diagnosis, reduce the incidence of maternal complications during pregnancy, reduce the risk of fetal death, and therefore improve the prognosis of the mother and the fetus.2. It is supposed that the increased of the experimental group VEGFR-1and Endoglin expression may have a relationship with the development of intrauterine fetal death.3. It is supposed that sVEGFR-1and sEng concentration in the mother’s amniotic fluid and the decreasing of PIGF in the experimental group may be associated with fetal death development.