Growth factors in preeclampsia: A vascular disease model. A failed vasodilation and angiogenic challenge from pregnancy onwards?

Preeclampsia is the major cause of maternofetal and neonatal morbi-mortality including intrauterine growth retardation, miscarriages and stillbirths. Inadequate vascular dilation and angiogenesis represent the crucial underlying defect of gravidic hypertension, denoting a failed response to the vasodilatory and pro-angiogenic challenge imposed by pregnancy, especially if multifetal. A similar pathogenesis appears involved in gestational diabetes. In this review we aimed to provide a hint on understanding the deeply involved angiogenic disorders which eventually culminate in utero-placental failure. The key players in these complex processes may be found in an intricate network of growth factors (GFs) and GF inhibitors, controlled by several vascular risk factors modulated by environment and genes, which eventually impact on early and late cardiovascular outcomes of mother and fetus.     

Correlations among antiangiogenic factors and trace elements in hypertensive disorders of pregnancy

Although a number of studies have measured circulating levels of some trace elements in preeclampsia (PE) and compared to healthy pregnant (HP), there is no consensus yet about the deficiency of some metals and development of hypertensive disorders in pregnancy. The aim of this study was to compare plasmatic levels of Zn, Mn, Co, Cu, Se and Sr among non-pregnant (NP), healthy pregnant (HP), gestational hypertensive (GH) and preeclamptic (PE) women and to correlate these levels with plasma soluble endoglin (sENG) and soluble fms-like tyrosine kinase-1 (sFLT-1), two important antiangiogenic proteins related to PE. A total of 184 women were enrolled in this study (NP = 35, GH = 51, PE = 37 and HP = 61). Trace element analyses were carried out with an inductively coupled plasma mass spectrometer (ICPMS). sENG and sFLT-1 plasma concentrations were measured by commercial ELISA kits. The most interesting result is that Sr is higher in PE (63%, P < 0.001) compared to HP and their levels are positively correlated with sENG in all three groups of pregnant women. Moreover, we found a negative correlation between Zn and sENG in HP (r = −0.43, P = 0.003). Regarding other elements, we found similar levels among pregnant groups. In conclusion, this study showed that Sr may has a role in physiopathology of PE.     

脐动脉血流对预测子痫前期新生儿和产妇结局的价值分析

目的:探讨应用脐动脉血流用于预测子痫前期新生儿和产妇结局的临床价值。方法:选择在我院产科建档分娩的120例孕产妇作为研究对象,根据子痫前期发病情况分为子痫前期组60例与对照组60例,记录和比较两组孕产妇的一般资料、血脂、血糖水平、分娩前脐动脉血流与新生儿体重、胎盘的重量及Apgar评分,并进行相关性与危险因素分析。结果:两组孕产妇的年龄、孕次、产次、流产次数、孕周等对比差异均无统计学意义(P0.05)。子痫前期组的血清HDL-C水平低于对照组(P0.05),血清TC、TG、LDL-C、FBG水平高于对照组(P0.05)。与对照组比较,子痫前期组脐动脉S/D、RI与PI值显著升高(P0.05)。所有孕产妇都顺利完成分娩,孕产妇与新生儿都存活,子痫前期组的新生儿出生体重及Apgar评分和胎盘的重量均显著低于对照组(P0.05)。在子痫前期组中,脐动脉S/D、RI、PI值与新生儿出生体重呈现显著负相关性(P0.05)。多重线性回归分析显示子痫前期孕产妇的脐动脉S/D、RI、PI值为影响新生儿出生体重的独立危险因素(P0.05)。结论:脐动脉血流与子痫前期新生儿出生体重显著相关,脐动脉S/D、RI、PI值为影响新生儿出生体重的独立危险因素,子痫前期脐动脉血流监测可为预测新生儿和产妇结局以及预后提供参考。     

Matrix metalloproteinase multiplex screening identifies increased MMP-2 urine concentrations in women predicted to develop preeclampsia

Background: Preeclampsia, a pregnancy disorder characterized by hypertension and proteinuria, represents the leading cause of fetal and maternal morbidity and mortality in developing countries. The identification of novel and accurate biomarkers that are predictive of preeclampsia is necessary to improve the prognosis of patients with preeclampsia.

Objective: The objective of this study is to evaluate the usefulness of nine urinary metalloproteinases to predict the risk of preeclampsia development.

Methods: MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-10, MMP-12 and MMP-13 were analyzed in urine (early-pregnancy) from 17 women predicted to develop preeclampsia and 48 controls using the Bio-Plex Pro-Human MMP panel (Bio-Rad, Hercules, CA).

Results: Urinary MMP-2 showed differences between groups which allowed us to calculate an increased risk for PE development of up to 20 times among the study population.

Conclusion: Increased urinary concentration of MMP-2 at 12 and 16 weeks of gestation predicted an increased risk of developing preeclampsia in the study population.     

子痫前期循环系统标志物sFlt-1的重组表达及化学发光检测方法的建立

目的: 表达可溶性fms样酪氨酸激酶-1(soluble fms-like tyrosine kinase-1,sFlt-1)重组蛋白,建立针对sFlt-1的化学发光检测方法。方法: 构建pcDNA3.4-sFlt-1-His*6表达载体,转染至HEK293细胞进行重组表达。利用链霉亲和素-生物素亲和体系及双抗体夹心法,实现对sFlt-1的定量检测。结果: 该方法的最低检测限为2 pg/mL,线性范围为20~40 000 pg/mL,平均回收率为92%,批内及批间精密度变异系数(variable coefficient,CV)均小于10%,与珀金埃尔默sFlt-1检测试剂盒进行比对的相关系数R²为0.925 2。结论: 获得了具有天然生物活性的sFlt-1蛋白,建立了具有良好性能的sFlt-1检测方法,后续进一步开发可应用于子痫前期的诊断筛查。     

Distribution of Notch protein members in normal and preeclampsia-complicated placentas

Notch proteins are a transmembrane receptor family that is structurally and functionally conserved from worms to humans. The mammalian family of Notch proteins consists of several genes encoding Notch receptors and related Notch ligands. Notch signaling is involved in different aspects of the cell-fate decision tree: differentiation, proliferation, and apoptosis. These three processes are finely regulated in human placenta in order to allow a successful pregnancy and correct fetal growth. Notch and its ligands also participate in vascular remodeling and stabilization. Vasculogenesis and blood regulation are of importance in the human placenta for normal fetal development and growth; any disorder of these systems leads to preeclampsia. Drawing on this background, we have investigated the expression of Notch-1, Notch-4, and Jagged-1, together with two members related to the Notch pathway in angiogenesis: VEGF and p21. Normal and preeclamptic human placentas have been evaluated by immunohistochemistry. In preeclamptic samples, a down-regulation of Notch pathway members occurs with a weak/moderate expression of the Notch protein members in all components of placenta compared with physiological placentas that, at term, exhibit the strong expression of Jagged-1 and a moderate expression of both Notch-1 and Notch-4 in all compartments of the placental villi. Moreover, preeclamptic samples also reveal a down-regulation of VEGF expression, together with a moderate nuclear expression of p21^Cip1 in the syncytiotrophoblast, cytotrophoblast, and endothelial cells. This down-regulation of VEGF in preeclamptic placentas, in turn, probably decreases Notch protein expression in placental compartments and in endothelial cells and could offer an ethiopathogenetic explanation for the onset of this pathology.     

Comparative analysis of maternal-fetal interface in preeclampsia and preterm labor

The maternal-fetal interface, a chimeric structure, is formed when fetal cytotrophoblasts (CTBs) from the placenta invade the uterine wall and its resident vasculature. In preeclampsia (PE), interstitial and endovascular invasion are often shallow, and fewer spiral arterioles are breached in toto. Our previous work has shown that faulty CTB differentiation to an invasive phenotype is a contributing factor. Here, we have tested the hypothesis that the constellation of morphological and molecular defects that are associated with PE are unique to this condition. Specifically, we have compared the histology of the maternal-fetal interface and CTB expression of stage-specific antigens in PE and in preterm labor (PTL) with or without inflammation. In the absence of inflammation, biopsies obtained after PTL were near normal at histological and molecular levels. In accord with previously published data, PE had severe negative effects on the endpoints analyzed. Biopsies obtained after PTL with inflammation had an intermediate phenotype. Our results suggest that the maternal-fetal interface from cases of PTL without inflammation can be used for comparative purposes, e.g., as age-matched controls, in studies of the effects of PE on cells in this region. This work was supported by the Intramural Division of NICHD (Perinatology Research Branch) and HD 30367.     

Plasma -arginine is markedly reduced in pregnant women affected by preeclampsia

The objective of this study was to determine the concentration of free -amino acids and in particular of -arginine in the plasma of pregnant women affected by preeclampsia compared to healthy pregnant women in order to know if an alteration in the concentrations of these amino acids occurs in preeclamspia. Twelve pregnant women affected by preeclampsia and twelve pregnant control women, ages 28–35 years old and at the 35–36 weeks of pregnancy were studied. The blood analysis of free amino acids was carried out by using a high performance liquid chromatographic (HPLC) fluorometric method and OPA-NAC as derivatizing agent for the amino acid determination. In the blood of women affected by preeclampsia -arginine is markedly reduced compared to controls (about five-fold lower, P<0.01). The other amino acids also are significantly reduced, but to lesser extents (about 1.5 times lower, P<0.05). Thus, the determination of -arginine in the blood of pregnant women could potentially constitute an additional marker for the early diagnosis of preeclampsia.