Angiogenic factors and prediction for ischemic placental disease in future pregnancies

The sFlt-1/PlGF-ratio and the risk of preeclampsia-related adverse outcomes in subsequent pregnancies with signs and symptoms of a preeclampsia

OBJECTIVES

This study characterizes the outcome of two subsequent pregnancies with suspected preeclampsia (PE). We investigated the diagnostic accuracy of clinical signs, Doppler examinations, and the soluble fms-like tyrosine kinase-1 (sFlt-1) to placental growth factor (PlGF)-ratio to predict PE-related adverse outcomes (AO). The sFlt-1/PlGF-ratio of the first pregnancy was compared to the outcome of the subsequent pregnancy.

STUDY DESIGN

A total of 1928 patients at risk for preeclampsia were screened, of them 1117 were eligible for inclusion. Of these, 84 women presented with suspected PE in two subsequent pregnancies.

OUTCOME MEASURES

Diagnostic accuracy of clinical markers was assessed. Associations between the sFlt-1/PlGF-ratio in the first and the odds of an AO in the subsequent pregnancy were investigated with logistic regression.

RESULTS

The prevalence of AOs decreased from 27.4 % in the first to 17.9 % in the second pregnancy. Comparison of the accuracy of the different clinical markers for an AO showed a high specificity for an sFlt-1/PlGF-ratio at the cut-off of ≥ 85 in both pregnancies (81.3 %, 95 % CI 63.6-92.8 vs 92.6 %,95 % CI 83.7-97.6), but a lower sensitivity in the second pregnancy (92.9 %, 95 % CI 66.1-99.8 vs 33.3%, 95 % CI 11.8-61.6). An elevated sFlt-1/PlGF-ratio in the first did not increase the odds of an AO in the subsequent pregnancy.

CONCLUSIONS

The prevalence of AOs decreases in subsequent pregnancies. Our finding that the sFlt-1/PlGF-ratio of the first was not related to the outcome of the subsequent pregnancy suggests that angiogenic markers are only a within-pregnancy short-term tool to assess AOs.

The role and expression of pro/antiangiogenic factors and microRNAs in gestational hypertension and pre-eclampsia

OBJECTIVE

Pre-eclampsia and gestational hypertension are two common hypertensive disorders of pregnancy with pre-eclampsia accounting for high foetal and maternal morbidity and mortality rate. These disorders have an unknown aetiology and their hypertensive and end-organ pathophysiology may present too late in pregnancy. This makes the identification of early detection and differentiation markers vital. MicroRNAs have strongly been associated with pregnancy and their imbalance has been associated with the angiogenic dysregulation seen in pre-eclampsia. This study assesses the expression of pro- and antiangiogenic factors and their corresponding microRNAs in the maternal circulation of patients with pre-eclampsia and gestational hypertension.

STUDY DESIGN

We analyzed angiogenic factors expression (sEng, TGF-β, VEGF) normalized against housekeeping gene β-actin and microRNAs (miRs: 210, 29B, 126) normalized against miR U6, potentially associated with pre-eclampsia and gestational hypertension using the targeted qPCR technique. These analytes were examined from early-onset (<34 weeks) (EOPE) (n = 12), late-onset (>34 weeks) (LOPE) (n = 12) pre-eclampsia, gestational hypertension (GH) (n = 12) and two gestationally matched normotensive groups (NG1 and 2) (n = 12) each in South African women of African ancestry. Group comparisons of experimental vs. control groups were assessed using t-test analysis for significance and represented as fold change expression.

RESULTS

The relative expression in group comparisons showed significant (p < 0.05) fold change of VEGF, TGF-β, sEng and miR126 in the EOPE vs. NG1. The GH vs. NG1 exhibited significant changes in VEGF, TGF-β, miR126, miR210 and miR29B. The LOPE vs. NG2 showed significant relative expression in all the angiogenic factors (VEGF, TGF-β and sEng). The GH vs. NG2 showed significant expression in VEGF and miR29B. The LOPE vs. EOPE showed significant fold changes in VEGF and miR210. Finally, only the GH vs. EOPE showed significant differences in miR210 and miR29B (p < 0.05).

CONCLUSION

This study provides better insights into angiogenic factors and microRNAs specificity to the subtypes of gestational hypertensive disorders in pregnancy. Relative expression analysis of angiogenic factors and microRNAs showed possible novel characteristics of gestational hypertension, and potential common molecular and pathological profiles with pre-eclampsia. Furthermore, we postulate that sEng and miR29B could be early detection markers for pre-eclampsia and gestational hypertension, respectively.

Literature Review: The sFlt1/PlGF Ratio and Pregestational Maternal Comorbidities: New Risk Factors to Predict Pre-Eclampsia

One of the main causes of maternal and neonatal morbidity and mortality is pre-eclampsia. It is characterized by a high sFlt1/PlGF ratio, according to prior research. Pregestational diseases in mothers may increase the risk of developing pre-eclampsia. Only a few studies have looked at the connection between maternal comorbidities before conception and the sFlt1/PlGF ratio. The most recent information regarding the association between maternal pregestational diseases and the ratio of sFlt1/PlGF is described in this review. The paper also examines current research suggesting that changes in pregnancy hormones and metabolites are related to a high sFlt1/PlGF ratio. Certain maternal disorders have been found to dramatically raise sFlt-1 and sFlt1/PlGF levels, according to an analysis of the literature. There is still debate about the data on the association between the sFlt1/PlGF ratio and maternal disorders such as HIV, acute coronary syndromes, cardiovascular function in the mother between 19 and 23 weeks of pregnancy, thyroid hormones, diabetes, and cancer. Additional research is needed to confirm these findings.

Placental Syndromes-A New Paradigm in Perinatology

Placental syndromes include pregnancy loss, fetal growth restriction, preeclampsia, preterm delivery, premature rupture of membranes, placental abruption and intrauterine fetal demise. This paper discusses the common etiopathogenesis of those syndromes and the role of angiogenic biomarkers in their development. Pregnancy implantation, placental development and maternal adaptation are complex processes in which fetal and maternal cells interact. The syncytiotrophoblast, trophoblast, uterine natural killer cells and regulatory T cells interfere and interact in all the above-mentioned processes. The proper angioneogenesis and vasculogenesis of the placenta, as well as maternal circulatory adaptation, are dependent on angiogenic factor expression. Insufficient maternal immunotolerance, dysregulation in uterine natural killer or regulatory T cell function, syncytiotrophoblast and trophoblast ischemia and hypoxia or impaired balance in angiogenic factors are all related to the occurrence of placental syndromes. Differences in the time of impairment onset and its intensity and correlation with other dysfunctions result in the development of a specific syndrome. The clinical manifestations in the form of a combination of specific symptoms determine the diagnosis. However, they are just symptoms of an underlying complex trophoblast disorder.