A Critical Review of Early-Onset and Late-Onset Preeclampsia

Soluble fms-like tyrosine kinase 1 and placental growth factor ratio for predicting preeclampsia in elderly gravida

Objective: To determine the predictive value of plasma soluble fms-like tyrosine kinase 1 (sFlt-1) and placental growth factor (PlGF) ratio for detection of preeclampsia in elderly gravida at 16-18 weeks of gestation and to identify whether abnormalities of this ratio are associated with any other pregnancy complications or not.Methods: Blood samples of 300 cases were collected. Plasma sFlt-1 and PlGF levels were measured using an automated immunoassay.Results: Sensitivity and specificity for plasma sFlt-1/PlGF ratio above 9.8 for preeclampsia prediction were 85.7% and 61.2%, respectively. The sensitivity and specificity to predict early onset preeclampsia were 100% and 61.1%, respectively. Women with abnormal plasma sFlt-1/PlGF ratio were not associated with any other pregnancy complications.Conclusion:  sFlt-1/PlGF ratio at 16-18 weeks of gestation in elderly gravida has a high sensitivity for predicting preeclampsia, especially early onset preeclampsia.

An Insight into the Angiogenic and Lymphatic Interplay in Pre-eclampsia Comorbid with HIV Infection

PURPOSE OF REVIEW

To provide insight on the imbalance of angiogenic and lymphangiogenic factors in pre-eclampsia, as well as highlight polymorphism in genes related to angiogenesis and lymphangiogenesis.

RECENT FINDINGS

The pregnancy-specific disorder pre-eclampsia is diagnosed by the presence of hypertension with/without proteinuria, after 20 weeks of gestation. The pathogenesis of pre-eclampsia remains ambiguous, but research over the years has identified an imbalance in maternal and foetal factors. Familial predisposition and gene variation are also linked to pre-eclampsia development. The sFlt-1/PIGF ratio has attracted great attention over the years; more recently several researchers have reported that a sFlt-1/PIGF ratio of ≤ 38 can be used to predict short-term absence of pre-eclampsia. This ratio has the potential to prevent adverse pregnancy outcomes and reduce healthcare costs significantly. Genome-wide studies have additionally identified variation in the foetal gene near Flt-1. The development of preeclampsia is not limited to the maternal interface, but foetal involvement as well as genetic interplay is associated with the disorder.

A maternal GOT1 novel variant associated with early-onset severe preeclampsia identified by whole-exome sequencing

BACKGROUND

This study wants to know the genetic cause of preeclampsia (PE) which is a leading cause of maternal and perinatal death, but the underlying molecular mechanisms that cause PE remain poorly understood. Many single nucleotide polymorphisms have been identified by genome-wide association studies and were found to be associated with PE; however, few studies have used whole-exome sequencing (WES) to identify PE variants.

METHODS

Five patients with severe early-onset preeclampsia (EOPE) were recruited, and WES was performed on each patient. Sanger sequencing was used to confirm the potential causative genetic variant.

RESULTS

After a stringent bioinformatics analysis, a rare variant in the GOT1 gene, c.44C > G:p.P15R, was found in one patient. Bioinformatics analysis showed that the variant site is highly conserved across several species and was predicted to be a pathogenic variant according to several online mutational function prediction software packages. Further structural biology homology modeling suggested that P15R would change the electric environment of enzymatic center, and might affect the binding affinity of substrate or product.

CONCLUSION

We demonstrated for the first time that the variant in GOT1 may be associated with EOPE, the results of this study provide researchers and clinicians with a better understanding of the molecular mechanisms that underlie maternal severe EOPE.

Changes in pregnancy-related serum biomarkers early in gestation are associated with later development of preeclampsia

Background

Placental protein expression plays a crucial role during pregnancy. We hypothesized that: (1) circulating levels of pregnancy-associated, placenta-related proteins throughout gestation reflect the temporal progression of the uncomplicated, full-term pregnancy, and can effectively estimate gestational ages (GAs); and (2) preeclampsia (PE) is associated with disruptions in these protein levels early in gestation; and can identify impending PE. We also compared gestational profiles of proteins in the human and mouse, using pregnant heme oxygenase-1 (HO-1) heterozygote (Het) mice, a mouse model reflecting PE-like symptoms.

Methods

Serum levels of placenta-related proteins–leptin (LEP), chorionic somatomammotropin hormone like 1 (CSHL1), elabela (ELA), activin A, soluble fms-like tyrosine kinase 1 (sFlt-1), and placental growth factor (PlGF)–were quantified by ELISA in blood serially collected throughout human pregnancies (20 normal subjects with 66 samples, and 20 subjects who developed PE with 61 samples). Multivariate analysis was performed to estimate the GA in normal pregnancy. Mean-squared errors of GA estimations were used to identify impending PE. The human protein profiles were then compared with those in the pregnant HO-1 Het mice.

Results

An elastic net-based gestational dating model was developed (R² = 0.76) and validated (R² = 0.61) using serum levels of the 6 proteins measured at various GAs from women with normal uncomplicated pregnancies. In women who developed PE, the model was not (R² = -0.17) associated with GA. Deviations from the model estimations were observed in women who developed PE (P = 0.01). The model developed with 5 proteins (ELA excluded) performed similarly from sera from normal human (R² = 0.68) and WT mouse (R² = 0.85) pregnancies. Disruptions of this model were observed in both human PE-associated (R² = 0.27) and mouse HO-1 Het (R² = 0.30) pregnancies. LEP outperformed sFlt-1 and PlGF in differentiating impending PE at early human and late mouse GAs.

Conclusions

Serum placenta-related protein profiles are temporally regulated throughout normal pregnancies and significantly disrupted in women who develop PE. LEP changes earlier than the well-established biomarkers (sFlt-1 and PlGF). There may be evidence of a causative action of HO-1 deficiency in LEP upregulation in a PE-like murine model.

A recent history of preeclampsia is associated with elevated central pulse wave velocity and muscle sympathetic outflow

We demonstrate that resting muscle sympathetic nerve activity is elevated in women with a recent history of preeclampsia relative to women who have recently had uncomplicated pregnancies and without a history of preeclampsia. Structural changes in the central arteries are associated with arterial stiffness following preeclampsia, independent of changes in the sympathetic nervous system. The structural changes are observed in these relatively young previously preeclamptic women, indicating elevated cardiovascular risk. Our data suggest that with aging (and the gradual loss of vascular protection for women, as established by others), this risk will become exaggerated compared with women who have had normal pregnancies.

Exosomal encapsulation of miR-125a-5p inhibited trophoblast cell migration and proliferation by regulating the expression of VEGFA in preeclampsia

This study is aimed to examine the association between umbilical cord blood (UCB) derived exosomal microRNA (miRNA) with preeclampsia (PE) and to further explore the mechanism of a key differential gene (hsa-miR-125a-5p) in preeclampsia. Umbilical cord blood exosomal miRNA(exo-miRNA) from normal pregnant women and pregnant women with preeclampsia was processed via miRNA sequencing. Quantitative real-time polymerase chain reaction (QRT-PCR) was performed to assess the expression of miR-125a-5p in normal and PE placental tissues and peripheral blood derived exosomes in the third trimester. Human trophoblast cell line HTR8/SVneo was assigned as the negative control and miR-125a-5p mimics. QRT-PCR and Western blot were performed to identify the expressions of miR-125a-5p and vascular endothelial growth factor A (VEGFA). CCK8, flow cytometry, wound-healing and Transwell assays were used to analyze the effect of miR-125a-5p on HTR8/SVneo cell migration, proliferation, and cycle distribution. Tube formation was performed to estimate the angiogenesis ability of miR-125a-5p on HUVECs. In conclusion, miR-125a-5p expression in PE placental tissues was higher than in normal subjects, while the expression of VEGFA was lower in PE placental tissues. We then compared the miR-125a-5p mimics group with the negative control group and found that in the mimics group, the cell migration, proliferation and angiogenesis abilities were decreased, and more cells were arrested in the S stage. Our study systematically profiled the UCB exo-miRNA in normal and PE pregnant women and demonstrated that dysregulation of miR-125a-5p might affect HTR8/SVneo cell proliferation and migration and inhibit angiogenesis by regulating VEGFA, indicating that miR-125a-5p is involved in the progression of PE.

Cardiovascular effects of severe late-onset preeclampsia are reversed within six months postpartum

OBJECTIVES

Preeclampsia (PE) is a common pregnancy-related disorder associated with cardiovascular long-term disease. Eighty percent are late-onset PE, occurring after 34 gestational weeks, and can present with severe symptoms. Magnitude and reversibility rate of maternal cardiovascular changes after severe late-onset PE have not been characterized. This study therefore evaluated longitudinal dynamics of maternal cardiovascular changes after severe late-onset PE.

STUDY DESIGN

Six previously normotensive women with severe late-onset PE and eight pregnant controls were included. Severe PE was defined as systolic blood pressure (SBP) ≥ 160 mmHg or diastolic blood pressure (DBP) ≥ 110 mmHg and proteinuria with/without evidence of end-organ dysfunction, or SBP ≥ 140 mmHg or DBP ≥ 90 mmHg with/without proteinuria and with evidence of end-organ dysfunction. Cardiovascular function was assessed by magnetic resonance imaging at 1-3 days, one week and six months postpartum.

RESULTS

Left ventricular mass at 1-3 days postpartum was higher after severe late-onset PE (57 g/m²) compared to after normal pregnancy (48 g/m²; p = 0.01). Pulse wave velocity (PWV) decreased between 1 and 3 days and six months postpartum after PE (6.1 to 5.0 m/s; p = 0.028). There was no difference in PWV 1-3 days postpartum after severe PE compared after normal pregnancy (6.1 versus 5.6 m/s; p = 0.175). Blood pressure normalized within six months in all but one patient.

CONCLUSIONS

Cardiac effects after severe late-onset PE were small and transient. This indicates that left ventricular hypertrophy after severe late-onset PE may be a secondary physiologic response to increased peripheral resistance in PE. Vascular mechanisms rather than persistent cardiac hypertrophy postpartum may be the culprit for increased long-term cardiovascular risk after PE.

The role of CXC chemokine ligand 16 in physiological and pathological pregnancies

The survival and development of a semi-allogeneic fetus during pregnancy require the involvement of a series of cytokines and immune cells. Chemokines are a type of special cytokine those were originally described as having a role in leukocyte trafficking. CXC chemokine ligand (CXCL) 16 is a member of the chemokine family, and CXC chemokine receptor (CXCR) 6 is its sole receptor. Emerging evidence has shown that CXCL16/CXCR6 is expressed at the maternal-fetal interface, by cell types that include trophoblast cells, decidual stroma cells, and decidual immune cells (eg, monocytes, γδT cells, and natural killer T (NKT) cells). The regulation of expression of CXCL16 is quite complex, and this process involves a multitude of factors. CXCL16 exerts a critical role in the establishment of a successful pregnancy through a series of molecular interactions at the maternal-fetal interface. However, an abnormal expression of CXCL16 is associated with certain pathological states associated with pregnancy, including recurrent miscarriage, pre-eclampsia, and gestational diabetes mellitus (GDM). In the present review, the expression and pleiotropic roles of CXCL16 under conditions of physiological and pathological pregnancy are systematically discussed.

Circulating endocan and preeclampsia: a meta-analysis

Background: Endocan, a novel protein involved in inflammation and endothelial dysfunction, has been suggested to be related to preeclampsia, although the results of previous studies were not consistent. The aim of the study was to evaluate the potential difference of circulating endocan in women with preeclampsia and those with normal pregnancy.

Methods: Matched case–control studies evaluating the difference of circulating endocan between women with preeclampsia and those with normal pregnancy were identified via systematic search of PubMed and Embase databases. A random-effect model or a fixed-effect model was used to pool the results according to the heterogeneity. Subgroup analysis was performed to evaluate whether the timing of preeclampsia onset affected the outcome.

Results: Overall, eight matched case–control studies, including 451 women with preeclampsia and 442 women with normal pregnancy were included. Significant heterogeneity was detected among the included studies (P for Cochrane’s Q test = 0.006, I² = 65%). Meta-analysis with a random-effect model showed that women with preeclampsia had significantly higher circulating level of endocan compared with women with normal pregnancy (standardized mean difference = 0.37, 95% confidence interval: 0.13–0.62, P = 0.003). Subsequent subgroup analyses showed that the difference of circulating endocan between women with early onset preeclampsia and those with normal pregnancy was not statistically different from that between women with late-onset preeclampsia and those with normal pregnancy (P for subgroup difference = 0.81).

Conclusions: Women with preeclampsia have higher circulating endocan than those with normal pregnancy.

Relationship between polymorphisms of CXCL3 gene and preeclampsia

Background: Preeclampsia (PE), a pregnancy-specific disease, is a main cause of maternal and perinatal mortality in the world, the exact pathogenesis of which is still unknown. Recent studies have found it is a disorder caused by multiple factors and genes. Previously, we found a significantly abnormal expression of CXCL3 in plasma and placenta of severe preeclampsia. Here, we intend to explore the association of polymorphisms in CXCL3 gene with preeclampsia susceptibility in women from western China.Methods: Four hundred eighty-one pregnant women were involved in this case-control study, including 83 early-onset severe preeclampsia cases, 114 late-onset severe preeclampsia cases, 41 mild preeclampsia cases and 243 normal pregnancies. The rs370655 variant in CXCL3 was detected by the method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).Results: No significantly reduced risk of preeclampsia is observed in the rs370655 AA genotype compared with other genotypes (AG versus AA: OR = .82, 95%CI = .54-1.26; GG versus AA: OR = .95, 95%CI = .56-1.61). After subgroup analysis, there are still no significant differences among various genotypes in the mild preeclampsia, early-onset severe preeclampsia and late-onset sever preeclampsia.Conclusion: Our study suggests that rs370655 polymorphism in CXCL3 gene may be not the risk factor of preeclampsia, exploring other consequential SNPs in CXCL3 gene may help to predict the preeclampsia.

CCN3 Signaling Is Differently Regulated in Placental Diseases Preeclampsia and Abnormally Invasive Placenta

OBJECTIVES

An adequate development of the placenta includes trophoblast differentiation with the processes of trophoblast migration, invasion, cellular senescence and apoptosis which are all crucial to establishing a successful pregnancy. Altered placental development and function lead to placental diseases such as preeclampsia (PE) which is mainly characterized by insufficient trophoblast invasion and abnormally invasive placenta (AIP) disorders (Placenta accreta, increta, or percreta) which are characterized by excessive trophoblast invasion. Both of them will cause maternal and fetal morbidity/mortality. However, the etiology of these diseases is still unclear. Our previous study has shown that the matricellular protein nephroblastoma overexpressed (NOV, CCN3) induces G0/G1 cell cycle arrest, drives trophoblast cells into senescence and activates FAK and Akt kinases resulting in reduced cell proliferation and enhanced migration capability of the human trophoblast cell line SGHPL-5. The present study focuses on whether CCN3 can alter cell cycle-regulated pathways associated with trophoblast senescence and invasion activity in pathological versus gestational age-matched control placentas.

METHODS

Cell cycle regulator proteins were investigated by immunoblotting and qPCR. For localization of CCN3, p16, p21, and Cyclin D1 proteins, co-immunohistochemistry was performed.

RESULTS

In early-onset PE placentas, CCN3 was expressed at a significantly lower level compared to gestational age-matched controls. The decrease of CCN3 level is associated with an increase in p53, Cyclin E1 and pRb protein expression, whereas the level of cleaved Notch-1, p21, Cyclin D1, pFAK, pAKT, and pmTOR protein decreased. In term AIP placentas, the expression of CCN3 was significantly increased compared to matched term controls. This increase was correlated to an increase in p53, p16, p21, Cyclin D1, cleaved Notch-1, pFAK, pAkt, and pmTOR whereas pRb was significantly decreased. However, in late PE and early AIP placentas, no significant differences in CCN3, p16, p21, Cyclin D1, p53, and cleaved Notch-1 expression were found when matched to appropriate controls.

CONCLUSIONS

CCN3 expression levels are correlated to markers of cell cycle arrest oppositely in PE and AIP by activating the FAK/AKT pathway in AIP or down-regulating in PE. This may be one mechanism to explain the different pathological features of placental diseases, PE and AIP.

Developmental origins of accelerated cardiovascular aging

The Barker hypothesis of fetal origins of disease, derived from observational epidemiological studies, has been modified by the realization that the early influences on cardiovascular development may be recognized in the fetus. Aging and developmental programming are both associated with oxidative stress and endothelial dysfunction, suggesting common mechanistic origins. Preeclampsia (PE) is the utmost variant of placental insufficiency and is associated with an increase of serum concentrations of inflammation and antiangiogenic agents in mother and fetus. All these factors are specific for the endothelial dysfunction and able to trigger the epigenetic programming of cardiovascular diseases and accelerated aging. The concentrations of cytokines, tumor necrosis factor, C-reactive protein, NO metabolites, endothelin-1 and homocysteine were measured in serum of women with a normal pregnancy (n=27), PE (n=30) and their newborn infants. The concentrations of all these factors were higher in serum of women and newborns of PE group than in serum of women and newborns of the normal group. The significantly positive correlation between factors concentrations in maternal and newborn’s serum was demonstrated in all groups. We suggest the common source of these agents to be the syncytiotrophoblast cells contacting with both maternal and fetal blood and play a significant role in intrauterine programming and epigenetic triggering of accelerated cardiovascular aging.

Peptide hormone ELABELA enhances extravillous trophoblast differentiation, but placenta is not the major source of circulating ELABELA in pregnancy

Preeclampsia is a frequent gestational hypertensive disorder with equivocal pathophysiology. Knockout of peptide hormone ELABELA (ELA) has been shown to cause preeclampsia-like symptoms in mice. However, the role of ELA in human placentation and whether ELA is involved in the development of preeclampsia in humans is not yet known. In this study, we show that exogenous administration of ELA peptide is able to increase invasiveness of extravillous trophoblasts in vitro, is able to change outgrowth morphology and reduce trophoblast proliferation ex vivo, and that these effects are, at least in part, independent of signaling through the Apelin Receptor (APLNR). Moreover, we show that circulating levels of ELA are highly variable between women, correlate with BMI, but are significantly reduced in first trimester plasma of women with a healthy BMI later developing preeclampsia. We conclude that the large variability and BMI dependence of ELA levels in circulation make this peptide an unlikely candidate to function as a first trimester preeclampsia screening biomarker, while in the future administering ELA or a derivative might be considered as a potential preeclampsia treatment option as ELA is able to drive extravillous trophoblast differentiation.

Placental protein expression of kisspeptin-1 (KISS1) and the kisspeptin-1 receptor (KISS1R) in pregnancy complicated by diabetes mellitus or preeclampsia

PURPOSE

Kisspeptins regulate the trophoblast invasion. The disturbance of this process might lead to the development of preeclampsia (PE). Diabetes mellitus (DM) is associated with the high rate of this complication. The main hypothesis was to investigate the placental protein expression of kisspeptin-1 (KISS1) and its receptor (KISS1R) in diabetic, preeclamptic, and healthy pregnancies.

METHODS

Placentae (n = 65) were divided into the following groups: the control group (n = 20), either PE or non-PE type-1 diabetes mellitus (T1DM) (n = 10), either PE or non-PE type-2 diabetes mellitus (T2DM) (n = 10), either PE or non-PE gestational diabetes mellitus (GDM) (n = 10) and preeclampsia without diabetes (PE) (n = 15). Immunohistochemistry analysis was used for demonstrating the presence and location of KISS1/KISS1R in placental tissue and to measure the area of immunopositive expression. Correlation analyses were performed to detect the links between protein expression of these biomarkers and the main obstetric outcomes.

RESULTS

The highest placental protein expressions of KISS1 were detected in the PE (35.4%) and GDM (33.2%) groups. In case of DM, levels of KISS1 expression depended on the presence of PE and were higher compared with DM no PE and control groups: (30.6%) in T1DM + PE and (30.1%) in T2DM + PE group. The lowest expression was detected in the control group (14.1%). The expression of KISS1R was higher in DM and PE compared to the control group. We detected the strong direct link between PE and placental expression of KISS1 (r = 0.81) and KISS1R (r = 0.56), and inverse correlation link between KISS1 and preterm birth weight (r = - 0.73). The low correlation links were found between KISS1 and IUGR (r = 0.29), and preterm birth (r = 0.24). The same trend was detected for KISS1R. We did not find any significant correlations between placental expressions of KISS/KISS1R and placental weight or HbA1c levels.

CONCLUSION

Increased expression levels of KISS1 and KISS1R in case of diabetes mellitus may play a role in the altered placentation process and lead to the development of preeclampsia.

Knowledge of preeclampsia and its associated factors among pregnant women: a possible link to reduce related adverse outcomes

Background

Pre-eclampsia (PE) is one of the leading causes of maternal morbidity and mortality globally. Adequate knowledge about a disorder contributes greatly to its prevention, control and management. This study assessed the level of knowledge of PE and evaluated the factors associated with knowledge adequacy among pregnant women attending antenatal care at a University Hospital in Kumasi-Ghana.

Methods

This cross-sectional study was conducted at the University Hospital in Kumasi, Ghana. A validated closed-ended questionnaire was used to collect socio-demographic information and history of PE. Knowledge of PE was assessed based on a series of questions regarding the awareness, signs/symptoms, risk factors and complications of PE. Responses were scored percentage-wise and grouped into low (< 60%), moderate (60–80%) and high (80–100%). Knowledge score was then re-stratified into adequate (% score of ≥60%) and inadequate knowledge of PE (% score of < 60%).

Results

The prevalence of inadequate and adequate knowledge of PE was 88.6% (mean score = 55.5 ± 4.3%) and 11.4% (mean score = 76.3 ± 5.9%), respectively. For participants with adequate knowledge of PE, 9.1% (mean score = 67.4 ± 6.9%) and 2.3% (mean score = 85.2 ± 5.1%) had moderate and high knowledge, respectively. Using univariate logistic regression models, being older (> 35 years old) [cOR = 3.09, 95%CI (0.88–10.88), p = 0.049] and having a higher level of education (> SHS education) [cOR = 4.45, 95%CI (2.18–9.10), p < 0.0001] were significantly associated with greater odds of having adequate knowledge of PE. After controlling for potential confounders in multivariate logistic regression analysis, we found higher level of education to be independently associated with adequate knowledge of PE [aOR = 2.87, 95%CI (1.31–6.30), p = 0.008].

Conclusion

The knowledge of PE among pregnant women in Ghana is low. The prominent factor that facilitates adequacy of knowledge of PE is higher level of education.

Effects of factor v Leiden polymorphism on the pathogenesis and outcomes of preeclampsia

Background

Factor V Leiden polymorphism is a well-recognized genetic factor in the etiology of preeclampsia. Considering that Ghana is recording high incidence of preeclampsia, we examined if factor V Leiden is a contributory factor to its development and pregnancy outcomes.

Methods

STROBE consensus checklist was adopted to recruit eighty-one (81) consenting subjects after ethical clearance. Subjects were followed up till delivery to obtain outcomes of PE. Routine blood chemistry and proteinuria were done on all samples. Factor V Leiden was characterized by polymerase chain reaction and restriction fragment length polymorphism (RFLP). The data was captured as protected health information (PHI) and analyzed with SPSS version 22.

Results

Overall allelic frequencies found in FVL exon 10 were 0.67 and 0.33 for G and A alleles respectively. The FVL mutation was more in PE and hypertensive patients. Increased white blood cells, increased uric acid and a three – fold increment of AST / ALT ratio was observed in PE cases when stratified by FVL exons (exon 8 and 10). Significant differences were also observed between FVL and age, systolic blood pressure (SBP), diastolic blood pressure (DBP), liver enzymes, white blood cells (wbc), hemoglobin levels.

Conclusion

FVL mutation allele frequency was 0.33, a first report. The mutation was associated with increased uric acid, liver enzymes and blood cell indices suggestive of acute inflammation.

Untargeted analysis of plasma samples from pre-eclamptic women reveals polar and apolar changes in the metabolome

INTRODUCTION

Pre-eclampsia is a hypertensive gestational disorder that affects approximately 5% of all pregnancies.

OBJECTIVES

As the pathophysiological processes of pre-eclampsia are still uncertain, the present case-control study explored underlying metabolic processes characterising this disease.

METHODS

Maternal peripheral plasma samples were collected from pre-eclamptic (n = 32) and healthy pregnant women (n = 35) in the third trimester. After extraction, high-resolution mass spectrometry-based untargeted metabolomics was used to profile polar and apolar metabolites and the resulting data were analysed via uni- and multivariate statistical approaches.

RESULTS

The study demonstrated that the metabolome undergoes substantial changes in pre-eclamptic women. Amongst the most discriminative metabolites were hydroxyhexacosanoic acid, diacylglycerols, glycerophosphoinositols, nicotinamide adenine dinucleotide metabolites, bile acids and products of amino acid metabolism.

CONCLUSIONS

The putatively identified compounds provide sources for novel hypotheses to help understanding of the underlying biochemical pathology of pre-eclampsia.

Circulating pentraxin-3 and preeclampsia: a meta-analysis of 17 case-control studies

Introduction: Change of circulating pentraxin-3 (PTX-3), a novel marker of inflammation, has been observed in women with preeclampsia (PE). However, results of previous studies were inconsistent. We performed a meta-analysis to evaluate the difference of circulating PTX-3 between women with PE and normal pregnancies.Methods: Case-control studies comparing circulating PTX-3 level between women with PE and normal pregnancies were identified via search of PubMed and Embase databases according to a predefined search strategy and inclusion criteria by two independent authors. Meta-analysis was performed with a random-effect model to incorporate heterogeneity.Results: Seventeen studies including 814 women with PE and 949 women with normal pregnancy were included. Results showed that women with PE had significantly higher circulating PTX-3 at diagnosis as compared to women with normal pregnancy (standardized mean difference [SMD]: = 1.74, 95% CI: 1.20-2.29, p < .001; I² = 94%). The results were consistent regardless of study characteristics including study location, maternal age, sample size, early or late onset of PE, blood sample for PTX-3 measurement, or NOS quality scores. Moreover, higher circulating PTX-3 was also observed before the diagnosis of PE (SMD = 0.65, 95% CI: 0.02-1.29, p = .04; I² = 87%).Conclusion: Women with PE have higher circulating PTX-3 than women with normal pregnancy. The elevated PTX-3 could be observed before the clinical onset of PE. Future studies are needed to determine whether PTX-3 is an active molecular in the pathogenesis of PE.

Serum Levels of Complement Factors C1q, Bb, and H in Normal Pregnancy and Severe Pre-Eclampsia

Background

This study aimed to determine the diagnostic role of serum levels of complement C1q, Bb, and H in nonpregnant women, women with normal pregnancy, and women with severe pre-eclampsia.

Material/Methods

Healthy nonpregnant women (n=30), women with early, middle, and late normal pregnancy (n=30, respectively), and women with severe pre-eclampsia (n=73) were studied. The pre-eclampsia study group included early-onset cases (n=43) and late-onset cases (n=30). Serum levels of Bb were determined by enzyme-linked immunosorbent assay (ELISA), and C1q and H were tested by a turbidimetric immunoassay method.

Results

In the pre-eclampsia study group, compared with women with normal pregnancy, serum levels of C1q remained stable throughout pregnancy, and Bb levels declined from mid-pregnancy (p=0.250). Serum levels of factor H increased in the middle and late stages of pregnancy, and C1q and H were lower in early-onset severe pre-eclampsia (p<0.001, p=0.009, respectively) and late-onset severe pre-eclampsia (p<0.001, p=0.031, respectively) compared with the early-onset control and late-onset control groups. Serum levels of Bb increased in early-onset severe pre-eclampsia (p=0.001) and late-onset severe pre-eclampsia (p=0.003) compared with early-onset control and late-onset control groups. The area under the receiver operator curve (ROC) for serum C1q, Bb, and H for the diagnosis of early-onset severe pre-eclampsia were 0.814 (95% CI, 0.712–0.917), 0.743 (95% CI, 0.638–0.859), and 0.681(95% CI, 0.556–0.806), and late-onset severe pre-eclampsia were 0.805 (95% CI, 0.694–0.913), 0.796 (95% CI, 0.680–0.911), and 0.662 (95% CI, 0.524–0.800).

Conclusions

The classical and alternative pathways of complement were activated in patients with severe pre-eclampsia. Serum levels of C1q, Bb, and H should be studied further as potential diagnostic markers for severe pre-eclampsia.

Trace Minerals, Heavy Metals, and Preeclampsia: Findings from the Boston Birth Cohort

Background Preeclampsia is a leading contributor to maternal and perinatal morbidity and mortality. In mice experiments, manganese (Mn) and selenium (Se) are protective whereas cadmium (Cd) is promotive for preeclampsia. Epidemiologic findings on these chemical elements have been inconsistent. To confirm experimental findings in mice, we examined associations of trace minerals (Mn and Se) and heavy metals (Cd, lead [Pb], and mercury [Hg]) with preeclampsia in a birth cohort. Methods and Results A total of 1274 women from the Boston Birth Cohort (enrolled since 1998) had complete data on the exposures and outcome. We measured Mn, Se, Cd, Pb, and Hg from red blood cells collected within 24 to 72 hours after delivery. We ascertained preeclampsia diagnosis from medical records. We used Poisson regression with robust variance models to estimate prevalence ratios (PRs) and 95% CIs. A total of 115 (9.0%) women developed preeclampsia. We observed evidence of a dose-response trend for Mn (P for trend<0.001) and to some extent for Cd (P for trend=0.009) quintiles. After multivariable adjustment, a 1 SD increment in Mn was associated with 32% lower risk of developing preeclampsia (PR=0.68; 95% CI, 0.54-0.86), whereas a 1 SD increment in Cd was associated with 15% higher risk of preeclampsia (PR=1.15; 95% CI, 0.98-1.36). Null associations were observed for Se, Pb, and Hg. Conclusions Findings from our cohort, consistent with evidence from mice experiments and human studies, indicate that women with lower blood concentration of Mn or higher Cd are more likely to develop preeclampsia.

Hypertensive disorders of pregnancy: Strategy to develop clinical peptide biomarkers for more accurate evaluation of the pathophysiological status of this syndrome

Hypertensive disorders of pregnancy (HDP) is the most common and widely known as serious complication of pregnancy. As this syndrome is a major leading cause of maternal, fetal, and neonatal morbidity/mortality worldwide, many studies have sought to identify candidate molecules as potential disease biomarkers (DBMs) for use in clinical examinations. Accumulating evidence over the past 2 decades that the many proteolytic peptides appear in human humoral fluids, including peripheral blood, in association with an individual's health condition. This review provides the potential utility of peptidomic analysis for monitoring for pathophysiological status in HDP, and presents an overview of current status of peptide quantification technology. Especially, the technical limitations of the methods used for DBM discovery in the blood are discussed.

Alterations in fibrin formation and fibrinolysis in early onset-preeclampsia: Association with disease severity

OBJECTIVE

; Early-onset preeclampsia is a rare pregnancy-specific disorder associated with significantly increased maternal and fetal morbidity and mortality. Whilst it is known that even normotensive pregnancies are associated with changes in clot formation and dissolution, the nature of how these changes differ in those with early onset preeclampsia has not been well established. We sought to evaluate parameters of fibrin formation and fibrinolysis in individuals with early onset preeclampsia in comparison to both pregnant and non-pregnant controls. Furthermore, such parameters were correlated with markers of disease severity in this patient cohort, including the presence of multiorgan involvement, the rate of disease progression and the extent of the anti-angiogenic state in this condition.

STUDY DESIGN

; Patients with early onset preeclampsia (N = 20) and both pregnant (N = 16) and non -pregnant (N = 16) controls were recruited from the cohort at a large urban maternity hospital which saw over 15,000 deliveries during the study period. Platelet poor plasma was prepared from collected whole blood and analysed for parameters of fibrin formation and fibrinolysis (lagtime to and rate of fibrin formation; PAI-1; PAI-2; D-dimer; plasmin-antiplasmin; tPA) in addition to markers of angiogenesis (sFLT-1; Endoglin) using commercially available specific immunoassays.

RESULTS

; The maximum rate of fibrin formation as well as PAI-1, PAI-2 and D-dimer levels were all significantly increased in those with early onset preeclampsia and pregnant controls when compared to non-pregnant controls without significant differences between the 2 former groups. Plasmin-antiplasmin levels were significantly reduced in a similar manner. tPA levels were significantly elevated in EOP compared to both pregnant and non-pregnant controls. EOP was associated with significantly increased anti-angiogenic factors (sFLT-1; Endoglin) when compared to both pregnant and non-pregnant controls.

CONCLUSION

; Markers of fibrin formation and fibrinolysis are significantly alerted in early onset preeclampsia; furthermore, certain markers correlate with disease severity in this patient cohort.

A Review of Angiogenic Imbalance in HIV-Infected Hypertensive Disorders of Pregnancy

PURPOSE OF REVIEW

This review provides a comprehensive insight into the angiogenic profile of hypertensive and normotensive pregnancies compromised by HIV infection. Furthermore, we evaluate the economic implementation of the sFlt-1/PlGF ratio and review the reports on therapeutic apheresis in limiting sFlt-1 production.

RECENT FINDINGS

In preeclampsia, an increased expression of sFlt-1 triggers angiogenic imbalance. Women of African ancestry have high levels of angiogenic factors than other racial groups. The sFlt-1/PlGF ratio shows promise in the early assessment of preeclampsia, while sFlt-1 apheresis restores angiogenic imbalance. Studies suggest antiretroviral therapy does not impact the angiogenic shift in preeclampsia development. The angiogenic profile in pregnant women of different races influences preeclampsia development. Despite the opposing immune response in HIV infection and preeclampsia, the HIV tat protein strongly mimics vascular endothelial growth factor (VEGF); hence, it is plausible to assume that HIV infection may ameliorate the angiogenic imbalance in preeclampsia.

Exosomal microRNA profiling in early and late onset preeclamptic pregnant women reflects pathophysiology

Background: Preeclampsia is the leading cause of maternal and fetal mortality due to the inability to diagnose and treat the disorder early in pregnancy. This is attributed to the complex pathophysiology and unknown etiology of the disorder, which is modulated by several known and unknown factors. Exosomes have recently been implicated as possible mediators of the pathogenesis of preeclampsia, with, however, no evidence linking these nanovesicles to the pathophysiology of preeclampsia and its subtypes. Methods: To better understand the pathophysiological role of exosomes in preeclampsia, we have analyzed the exosomal microRNA in early and late onset preeclamptic women in comparison to their gestationally matched normotensive controls using Digital Direct Detection (NanoString Technologies). Results: For the first time, distinct exosomal microRNA signatures in early and late onset preeclampsia have been identified. Moreover, these signatures indicate that exosomes are involved in key pathological features associated with preeclampsia and differentiate between the subtypes. Conclusion: This study forms the basis for the diagnostic and functional validation of the identified signatures as biomarkers of preeclampsia and its subtypes.

First trimester complete blood cell indices in early and late onset preeclampsia

Objective

This study aimed to compare the first trimester complete blood count (CBC) indices of pregnancies complicated by early-onset preeclampsia (EOPE) or late-onset preeclampsia (LOPE).

Material and Methods

A retrospective case-control study was conducted with 186 patients. Patients were classified into three subgroups: EOPE, LOPE, and control groups. First trimester CBC results were obtained for each patient. Hemoglobin, hematocrit, red blood cell distribution width, mean corpuscular volume, white blood cell (WBC) count, neutrophil, eosinophil, basophil, lymphocyte, monocyte, mean platelet volume, platelet distribution width, plateletcrit, and platelet count were compared. The neutrophil lymphocyte ratio was calculated by dividing the absolute lymphocyte count by the absolute neutrophil count. The platelet lymphocyte ratio was calculated by dividing the absolute lymphocyte count by the absolute platelet count.

Results

The total number of cases was 21, 42, and 123, in the EOPE, LOPE, and control groups, respectively. There were statistically significant differences in the total WBC and neutrophil counts between the three groups (both p<0.05). WBC and neutrophil counts were found to be highest in the EOPE group, and the LOPE group had higher levels compared with controls. The optimal cut-off values to predict EOPE for WBC and neutrophil counts were 9.55×10³/ μL (sensitivity 71.4% and specificity 70.7%) and 6.45×10³/μL (sensitivity 66.7% and specificity 74.8%), respectively.

Conclusion

Increased first trimester WBC and neutrophil counts may be predictive for EOPE.

Differential Dynamics of the Maternal Immune System in Healthy Pregnancy and Preeclampsia

Preeclampsia is one of the most severe pregnancy complications and a leading cause of maternal death. However, early diagnosis of preeclampsia remains a clinical challenge. Alterations in the normal immune adaptations necessary for the maintenance of a healthy pregnancy are central features of preeclampsia. However, prior analyses primarily focused on the static assessment of select immune cell subsets have provided limited information for the prediction of preeclampsia. Here, we used a high-dimensional mass cytometry immunoassay to characterize the dynamic changes of over 370 immune cell features (including cell distribution and functional responses) in maternal blood during healthy and preeclamptic pregnancies. We found a set of eight cell-specific immune features that accurately identified patients well before the clinical diagnosis of preeclampsia (median area under the curve (AUC) 0.91, interquartile range [0.82-0.92]). Several features recapitulated previously known immune dysfunctions in preeclampsia, such as elevated pro-inflammatory innate immune responses early in pregnancy and impaired regulatory T (Treg) cell signaling. The analysis revealed additional novel immune responses that were strongly associated with, and preceded the onset of preeclampsia, notably abnormal STAT5ab signaling dynamics in CD4⁺T cell subsets (AUC 0.92, p = 8.0E-5). These results provide a global readout of the dynamics of the maternal immune system early in pregnancy and lay the groundwork for identifying clinically-relevant immune dysfunctions for the prediction and prevention of preeclampsia.

The prediction of early preeclampsia: Results from a longitudinal proteomics study

OBJECTIVES

To identify maternal plasma protein markers for early preeclampsia (delivery <34 weeks of gestation) and to determine whether the prediction performance is affected by disease severity and presence of placental lesions consistent with maternal vascular malperfusion (MVM) among cases.

STUDY DESIGN

This longitudinal case-control study included 90 patients with a normal pregnancy and 33 patients with early preeclampsia. Two to six maternal plasma samples were collected throughout gestation from each woman. The abundance of 1,125 proteins was measured using high-affinity aptamer-based proteomic assays, and data were modeled using linear mixed-effects models. After data transformation into multiples of the mean values for gestational age, parsimonious linear discriminant analysis risk models were fit for each gestational-age interval (8-16, 16.1-22, 22.1-28, 28.1-32 weeks). Proteomic profiles of early preeclampsia cases were also compared to those of a combined set of controls and late preeclampsia cases (n = 76) reported previously. Prediction performance was estimated via bootstrap.

RESULTS

We found that 1) multi-protein models at 16.1-22 weeks of gestation predicted early preeclampsia with a sensitivity of 71% at a false-positive rate (FPR) of 10%. High abundance of matrix metalloproteinase-7 and glycoprotein IIbIIIa complex were the most reliable predictors at this gestational age; 2) at 22.1-28 weeks of gestation, lower abundance of placental growth factor (PlGF) and vascular endothelial growth factor A, isoform 121 (VEGF-121), as well as elevated sialic acid binding immunoglobulin-like lectin 6 (siglec-6) and activin-A, were the best predictors of the subsequent development of early preeclampsia (81% sensitivity, FPR = 10%); 3) at 28.1-32 weeks of gestation, the sensitivity of multi-protein models was 85% (FPR = 10%) with the best predictors being activated leukocyte cell adhesion molecule, siglec-6, and VEGF-121; 4) the increase in siglec-6, activin-A, and VEGF-121 at 22.1-28 weeks of gestation differentiated women who subsequently developed early preeclampsia from those who had a normal pregnancy or developed late preeclampsia (sensitivity 77%, FPR = 10%); 5) the sensitivity of risk models was higher for early preeclampsia with placental MVM lesions than for the entire early preeclampsia group (90% versus 71% at 16.1-22 weeks; 87% versus 81% at 22.1-28 weeks; and 90% versus 85% at 28.1-32 weeks, all FPR = 10%); and 6) the sensitivity of prediction models was higher for severe early preeclampsia than for the entire early preeclampsia group (84% versus 71% at 16.1-22 weeks).

CONCLUSION

We have presented herein a catalogue of proteome changes in maternal plasma proteome that precede the diagnosis of preeclampsia and can distinguish among early and late phenotypes. The sensitivity of maternal plasma protein models for early preeclampsia is higher in women with underlying vascular placental disease and in those with a severe phenotype.

Increased circulating levels of Epidermal Growth Factor-like Domain 7 in pregnant women affected by preeclampsia

Proper placental development is crucial to establish a successful pregnancy. Defective placentation is the major cause of several pregnancy complications, including preeclampsia (PE). We have previously demonstrated that the secreted factor Epidermal Growth Factor-like Domain 7 (EGFL7) is expressed in trophoblast cells of the human placenta and that it regulates trophoblast migration and invasion, suggesting a role in placental development. In the present study, we demonstrate that circulating levels of EGFL7 are undetectable in nonpregnant women, increase during pregnancy and decline toward term. Close to term, circulating levels of EGFL7 are significantly higher in patients affected by PE when compared to normal pregnancies. Consistent with these results, villus explant cultures obtained from placentas affected by PE display increased release of EGFL7 in the culture medium when compared to those from normal placentas. Our results suggest that increased release of placenta-derived EGFL7 and increased circulating levels of EGFL7 are associated with the clinical manifestation of PE.

Omega-3 fatty acids differentially influences embryotoxicity in subtypes of preeclampsia

Background: Early (EOP) and late onset (LOP) preeclampsia are two subtypes of preeclampsia. This study examines the effect of maternal omega-3 fatty acids and vitamin E supplementation in a rat model of preeclampsia.Method: Pregnant Wistar rats were assigned to control; EOP; LOP; EOP+omega-3 fatty acid supplementation+vitamin E and LOP+omega-3 fatty acid supplementation+vitamin E. L-Nitroarginine methylester was used to induce preeclampsia. Blood Pressure (BP) was recorded during pregnancy and dams were dissected at d14 and d20 of gestation.Results: Animals from EOP and LOP groups demonstrated higher systolic and diastolic BP, lower weight gain, lower conceptuses size, lower conceptuses weight and fetal weight as compared to control. EOP and LOP groups showed higher percentage of fetal resorptions and embryotoxicity (deformities and hematomas).Conclusion: Supplementation reduced the diastolic BP, percentage of resorptions and embryotoxicity only in the LOP group, suggesting a need for differential supplementation regime for the two subtypes of preeclampsia.

Early onset preeclampsia in a model for human placental trophoblast

Preeclampsia, a leading cause of maternal and perinatal morbidity and mortality worldwide, is accompanied by shallow placentation and deficient remodeling of the uterine spiral arteries by invasive placental trophoblast cells during the first trimester of pregnancy. Here, we generated induced pluripotent stem cells from umbilical cords of normal pregnancies and ones complicated by early onset preeclampsia (EOPE) and converted them to trophoblast to recapitulate events of early pregnancy. Parameters disturbed in EOPE, including trophoblast invasiveness, were assessed. Under low O₂, both sets of cells behaved similarly, but, under the more stressful 20% O₂ conditions, the invasiveness of EOPE trophoblast was markedly reduced. Gene expression changes in EOPE trophoblast suggested a dysregulation invasion linked to high O₂.

We describe a model for early onset preeclampsia (EOPE) that uses induced pluripotent stem cells (iPSCs) generated from umbilical cords of EOPE and control (CTL) pregnancies. These iPSCs were then converted to placental trophoblast (TB) representative of early pregnancy. Marker gene analysis indicated that both sets of cells differentiated at comparable rates. The cells were tested for parameters disturbed in EOPE, including invasive potential. Under 5% O₂, CTL TB and EOPE TB lines did not differ, but, under hyperoxia (20% O₂), invasiveness of EOPE TB was reduced. RNA sequencing analysis disclosed no consistent differences in expression of individual genes between EOPE TB and CTL TB under 20% O₂, but, a weighted correlation network analysis revealed two gene modules (CTL4 and CTL9) that, in CTL TB, were significantly linked to extent of TB invasion. CTL9, which was positively correlated with 20% O₂ (P = 0.02) and negatively correlated with invasion (P = 0.03), was enriched for gene ontology terms relating to cell adhesion and migration, angiogenesis, preeclampsia, and stress. Two EOPE TB modules, EOPE1 and EOPE2, also correlated positively and negatively, respectively, with 20% O₂ conditions, but only weakly with invasion; they largely contained the same sets of genes present in modules CTL4 and CTL9. Our experiments suggest that, in EOPE, the initial step precipitating disease is a reduced capacity of placental TB to invade caused by a dysregulation of O₂ response mechanisms and that EOPE is a syndrome, in which unbalanced expression of various combinations of genes affecting TB invasion provoke disease onset.

Involvement of the PD-1/PD-L1 Co-Inhibitory Pathway in the Pathogenesis of the Inflammatory Stage of Early-Onset Preeclampsia

The programmed cell death protein 1 (PD-1) receptor has been reported to downregulate T cell activation effectively via binding to its ligands PD-L1 or PD-L2 in a negative co-stimulatory manner. Little is known about the involvement of PD-1 mediated immunoregulation in pregnancy and in pregnancy-related disorders. In this work, we investigated the possible role of the PD-1 co-stimulatory pathway in the pathogenesis of the clinical phase of early-onset preeclampsia characterized by a systemic maternal inflammatory response. We performed a cross-sectional study for comparative analysis of phenotypic and functional characteristics of peripheral blood mononuclear cells in women with early-onset preeclampsia and third-trimester healthy pregnant controls. According to our findings, enhanced expression of either PD-1 or its ligand PD-L1, or both, on the cell surface of effector cells (T cells, natural killer (NK) cells, natural killer T (NKT)-like cells) and Tregs could be observed, but PD-1 expression did not correlate with effector cells exhaustion. These results suggest the failure of the axis to downregulate Th1 responses, contributing thereby to the exaggerated immunoactivation observed in early-onset preeclampsia.

Circulating GATA2 mRNA is decreased among women destined to develop preeclampsia and may be of endothelial origin

Preeclampsia is a pregnancy complication associated with elevated placental secretion of anti-angiogenic factors, maternal endothelial dysfunction and organ injury. GATA2 is a transcription factor expressed in the endothelium which regulates vascular homeostasis by controlling transcription of genes and microRNAs, including endothelial miR126. We assessed GATA2 and miR126 in preeclampsia. Whole blood circulating GATA2 mRNA and miR126 expression were significantly decreased in women with established early-onset preeclampsia compared to gestation-matched controls (p = 0.002, p < 0.0001, respectively). Using case-control groups selected from a large prospective cohort, whole blood circulating GATA2 mRNA at both 28 and 36 weeks' gestation was significantly reduced prior to the clinical diagnosis of preeclampsia (p = 0.012, p = 0.015 respectively). There were no differences in GATA2 mRNA or protein expression in preeclamptic placentas compared to controls, suggesting the placenta is an unlikely source. Inducing endothelial dysfunction in vitro by administering either tumour necrosis factor-α or placenta-conditioned media to endothelial cells, significantly reduced GATA2 mRNA expression (p < 0.0001), suggesting the reduced levels of circulating GATA2 mRNA may be of endothelial origin. Circulating GATA2 mRNA is decreased in women with established preeclampsia and decreased up to 12 weeks preceding onset of disease. Circulating mRNAs of endothelial origin may be a novel source of biomarker discovery for preeclampsia.

Respiratory Morbidity in Late Preterm and Term Babies Born by Elective Caesarean Section

OBJECTIVE

This study sought to determine the incidence and severity of respiratory morbidity among late preterm and term babies born by elective Caesarean section (CS) in London, Ontario.

METHODS

A retrospective chart review was conducted of all elective CSs performed at or beyond 36⁰ weeks gestation from June 2010 to June 2014 at London Health Sciences Centre and St. Joseph's Health Care (Canadian Task Force Classification II-2).

RESULTS

The main indications for elective CS were previous CS (59.3%) and malpresentation (24.2%). The majority of elective CSs were performed at 38 weeks (34.1%) and 39 weeks (40.1%). Although only 3.7% of babies born by elective CS were found to have respiratory morbidity, 85% of these babies were admitted to the neonatal intensive care unit (NICU), and 15% required additional observation through a triage period. The relative risk of respiratory morbidity with elective CS at ≤38⁶ weeks compared with ≥39⁰ weeks was 2.14 (P = 0.0110). Only 3.5% of patients received antenatal steroids. There was an increased level of intervention among the babies admitted to the NICU for respiratory morbidity; 47.8%, 19.6%, 60.8%, and 15.25% required oxygen supplement, bag and mask, continuous positive airway pressure, and intubation with mechanical ventilation, respectively.

CONCLUSION

The risk of respiratory morbidity was significantly higher following elective CS before 39 weeks gestation. This resulted in increased length of stay and increased requirements for intravenous lines, blood draws, and exposure to antibiotics. This study provides further evidence that uncomplicated elective CS should be performed at ≥39 weeks, and interventions, such as preoperative antenatal steroid administration, may be considered if elective CS is medically indicated before 39 weeks.

First trimester 3D ultrasound placental volume for predicting preeclampsia and/or intrauterine growth restriction

The objective of the study was to determine the sensitivity of the placental volume for predicting preeclampsia and/or intrauterine growth restriction (IUGR) in the first trimester. A prospective observational study was conducted in pregnant women with a gestational age of 11 to 13⁺⁶ weeks. A 3 D transabdominal placental volume measurement was performed at the time of first-trimester aneuploidy screening. The predictive values of this test were calculated. The data from 360 pregnant women was analysed. Seventeen cases developed preeclampsia and/or IUGR. The 10^th percentile of placental volume was used as the cut-off level. The sensitivity, specificity, positive predictive value and negative predictive value of placental volume less than the 10^th percentile for prediction of preeclampsia and/or IUGR were 23.5%, 90.7%, 11.1% and 96%, respectively. The sensitivity, specificity, positive predictive value and negative predictive value for prediction of early onset preeclampsia were 50%, 90.7%, 3.0% and 99.7%, respectively. This study demonstrated that the placental volume was lower in the cases with preeclampsia and/or IUGR. It was not an effective screening tool for preeclampsia and/or IUGR in the first trimester. IMPACT STATEMENT What is already known on this subject? Placental volume may reflect trophoblast invasion, but much earlier, in the first trimester. The estimation of a smaller early placental volume has been shown to be significantly associated with preeclampsia and IUGR. What do the results of this study add? The placental volume was lower in the cases with preeclampsia and/or IUGR. It was not an effective screening tool for preeclampsia and/or IUGR in the first trimester. But it might be used for predicting early onset preeclampsia. What are the implications of these findings for clinical practice and/or further research? Further research of placental volume in the first trimester for predicting an early onset preeclampsia should be conducted.

Serum sFlt-1/PlGF ratio has better diagnostic ability in early- compared to late-onset pre-eclampsia

Background To establish gestational specific cutoffs for the soluble fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) ratio as a diagnostic tool for pre-eclampsia (PE) in an Asian population. Methods 82 subjects (48 PE patients and 34 controls) were recruited. sFlt-1 and PlGF were analysed on the Roche Cobas e411 analyzer and their ratio was calculated. Diagnostic performance was evaluated using receiver-operating characteristics (ROC) curves. Optimal cutoffs for sFlt-1/PlGF ratio were determined for different gestation phases. Results The most optimal cut-off for the study group is 32 with a sensitivity and specificity of 85.1% and 100% and Youden Index (J) of 0.85. Applying this cutoff for early-onset PE (EO-PE), sensitivity increased to 95.8% while specificity remains at 100% (J=0.96). However, for late onset PE (LO-PE), sensitivity decreases to 73.9% while specificity remains at 100% (J=0.74). Two cutoffs were further determined for EO-PE and LO-PE - the first focusing on high sensitivity; the second focusing on high specificity. For EO-PE, cutoff <17 yielded sensitivity of 100% and specificity of 94.4% (J=0.94) while cutoff ≥32 yielded sensitivity of 95.8% and specificity of 100% (J=0.95). For LO-PE, cutoff <22 has a sensitivity of 82.6% and a specificity of 91.7% (J=0.74) while cutoff ≥32 yielded sensitivity of 73.9% and specificity of 100% (J=0.74). Conclusion While our study found an overall cutoff at 32 regardless of gestation age, it has limited diagnostic accuracy for LO-PE in our study. Multiple cutoffs focusing on either high sensitivity or high specificity enhance the performance of the sFlt-1/PlGF ratio as a diagnostic tool for PE and contribute to the identification of women at risk of PE in our Asian region.

Telomere Homeostasis and Senescence Markers Are Differently Expressed in Placentas From Pregnancies With Early- Versus Late-Onset Preeclampsia

BACKGROUND

Early-onset preeclampsia (EOPE; <34 weeks' gestation) usually has more severe morbidity for the mother and fetus compared to late-onset preeclampsia (LOPE). Telomere homeostasis is disrupted in preeclampsia (PE) and senescence markers are increased. The pathophysiologic differences between early and LOPE are not fully unraveled yet.

METHODS

We studied placental biopsies from 7 pregnancies with EOPE, 6 pregnancies with LOPE, and 13 healthy gestational age-matched controls. Telomere length and aggregate formation were assessed using qualitative fluorescence in situ hybridization and electronic quantitative methods. Senescence markers were evaluated including senescence-associated heterochromatin foci, β-galactosidase (SAβ-Gal), and P16 staining, as was the expression of P16 complementary DNA (cDNA) using real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

There were no differences in maternal age, gravidity, parity, body mass index, and mode of conception between the study and the control groups. The percentage of trophoblasts with short telomeres was higher in placental samples from EOPE (52.61% [12.27%]) versus LOPE (28.72% [10.14%]); both were higher compared to controls (7.53% [5.14%], P = .03). Aggregate formation was enhanced in EOPE (8.72% [2.49%]) compared to LOPE (4.54% [1.45%]); both were higher than in healthy controls (2.72% [1.08%], P = .03). Trophoblasts from EOPE versus LOPE were more likely to stain positive for SAβ-Gal and P16 compared to controls (P < .001). P16 cDNA expression assayed by RT-qPCR was 7.51 times higher in EOPE compared to controls and 5.86 times higher than in LOPE.

CONCLUSIONS

Impaired telomere homeostasis and senescence markers are more prominent in EOPE versus LOPE. These findings may contribute to our understanding of the pathophysiology and explain their different clinical presentations and outcomes.

Fetal human leukocyte antigen-C and maternal killer-cell immunoglobulin-like receptors in cases of severe preeclampsia

INTRODUCTION

The pathogenesis of preeclampsia may involve inadequate trophoblast invasion caused by excessive inhibition of uterine natural killer cells (uNK) by extravillous trophoblast cells (EVT). This may be the result of a combination of maternal killer-cell immunoglobin-like receptor (KIR) AA genotype and fetal human leukocyte antigen-C2 (HLA-C2) genotype. A few studies have reported a significantly increased frequency of the maternal KIR AA/fetal HLA-C2 combination in cases of preeclampsia compared to controls.

METHODS

Study subjects were 259 cases of severe preeclampsia/eclampsia and 259 matched pregnant women without preeclampsia or eclampsia. All pregnancies were singleton pregnancies, and mothers were preferentially primigravidae. Blood samples from women and their newborns were obtained from the Danish National Birth Cohort (DNBC) and the Danish Neonatal Screening Biobank. Significant differences in the frequencies of KIR AA and HLA-C2 between cases and controls were investigated.

RESULTS

No significant difference was observed between cases and controls in the frequency of maternal KIR AA (OR = 0.86, 95%CI = 0.60-1.23, P = 0.41), neither when the fetus carried an HLA-C2 allele (OR = 0.85, 95%CI = 0.52-1.38, P = 0.51), nor when the fetus carried an HLA-C2 allele more than its mother (OR = 0.75, 95%CI = 0.34-1.64, P = 0.47).

CONCLUSION

The Results show no influence of HLA-C/KIR genetic variation on the risk of severe preeclampsia, contrary to what some previous studies have observed. An explanation could be that severe preeclampsia represents a separate pathological entity compared to mild preeclampsia.

Circulating Heme Oxygenase-1: Not a Predictor of Preeclampsia but Highly Expressed in Pregnant Women Who Subsequently Develop Severe Preeclampsia

Preeclampsia is the major cause of maternal and fetal deaths worldwide. Circulating biomarker concentrations to predict preeclampsia must be determined. Therefore, the objective was to evaluate heme oxygenase-1 (HO-1) concentration in both plasma and urine samples from pregnant women before the development of preeclampsia and to identify a potential biomarker for preeclampsia development. We performed a case-control study nested in a prospective study cohort at University Hospital of the Ribeirao Preto Medical School, University of São Paulo (HCFMRP-USP), Ribeirao Preto, Brazil. Of 1400 pregnant women evaluated at 20–25 weeks of gestation, 460 delivered in hospitals outside our institution. Of 940 pregnant women who completed the protocol, 30 developed preeclampsia (cases, 14 cases of severe preeclampsia and 16 cases of mild preeclampsia). Healthy pregnant women (controls, n = 90) were randomly selected from the remaining 910 participants. HO-1 concentration was evaluated in plasma/urine samples by using a commercial enzyme-linked immunosorbent assay kit. We found similar HO-1 levels in the plasma and urine for case and control groups. In the subgrouped preeclampsia, lower plasma HO-1 levels were found in mild compared with severe preeclampsia. We conclude that plasma HO-1 levels were not altered at 20–25 weeks of gestation before the manifestation of preeclampsia symptoms. Pregnant women who subsequently develop severe preeclampsia show higher expression of HO-1. This may be indicative of important underlying pathophysiologic mechanisms that differentiate between mild and severe preeclampsia and may possibly be related to a higher prooxidative status even before the development of clinical symptoms.

P-Glycoprotein (P-gp)/ABCB1 plays a functional role in extravillous trophoblast (EVT) invasion and is decreased in the pre-eclamptic placenta

Dysregulation of trophoblast differentiation is implicated in the placental pathologies of intrauterine growth restriction and pre‐eclampsia. P‐glycoprotein (P‐gp encoded by ABCB1) is an ATP‐binding cassette transporter present in the syncytiotrophoblast layer of the placenta where it acts as a molecular sieve. In this study, we show that P‐gp is also expressed in the proliferating cytotrophoblast (CT), the syncytiotrophoblast (ST) and the extravillous trophoblast (EVT), suggesting our hypothesis of a functional role for P‐gp in placental development. Silencing of ABCB1, via siRNA duplex, results in dramatically reduced invasion and migration, and increased tube formation and fusion in the EVT‐like HTR8/SV_neo cell line. In both EVT and CT explant differentiation experiments, silencing of ABCB1 leads to induction of the fusion markers human hCG, ERVW‐1 and GJA1 and terminal differentiation of both trophoblast subtypes. Moreover, P‐gp protein levels are decreased in both the villous and the EVT of severe early‐onset pre‐eclamptic placentas. We conclude that, in addition to its role as a syncytial transporter, P‐gp is a key factor in the maintenance of both CT and EVT lineages and that its decrease in severe pre‐eclampsia may contribute to the syncytial and EVT placental pathologies associated with this disease.

Fetal sexual dimorphism in systemic soluble fms-like tyrosine kinase 1 among normotensive and preeclamptic women

PROBLEM

A handful of studies report sexual dimorphism in the maternal angiogenic profile possibly influencing placental development and preeclampsia risk. This secondary analysis explored associations between fetal sex and soluble fms-like tyrosine kinase-1 (sFLT) and endoglin (9-35 weeks gestation) using data from a nested case-control study within the Danish National Birth Cohort.

METHOD OF STUDY

A total of 448 preeclamptic women and 328 normotensive women had data on sFLT and endoglin. Preeclampsia was defined by blood pressure ≥140/90 mm Hg and proteinuria (≥0.3g or 300 mg/24 h.). Generalized linear models adjusting for gestational age of blood draw, body mass index, maternal age, and smoking determined associations between fetal sex and log-transformed biomarkers.

RESULTS

Male fetal sex is associated with 11% lower sFLT levels (β = -0.11, P = 0.03) in preeclamptic women. There were no differences observed in normotensive women. We found no statistically significant differences in endoglin by fetal sex among groups.

CONCLUSION

Our results are similar with other studies suggesting that women with female fetuses have increased sFLT levels. However, significant difference was only among women with preeclampsia. This study was exploratory and longitudinal investigations across pregnancy are required to understand the relationship between fetal sex and systemic maternal angiogenic biomarkers.

Environmental noise pollution and risk of preeclampsia

BACKGROUND

Environmental noise exposure is associated with a greater risk of hypertension, but the link with preeclampsia, a hypertensive disorder of pregnancy, is unclear.

OBJECTIVES

We sought to determine the relationship between environmental noise pollution and risk of preeclampsia during pregnancy.

METHODS

We analyzed a population-based cohort comprising 269,263 deliveries on the island of Montreal, Canada between 2000 and 2013. We obtained total environmental noise pollution measurements (LA_eq24, L_den, L_night) from land use regression models, and assigned noise levels to each woman based on the residential postal code. We computed odds ratios (OR) and 95% confidence intervals (CI) for the association of noise with preeclampsia in mixed logistic regression models with participants as a random effect, and adjusted for air pollution, neighbourhood walkability, maternal age, parity, multiple pregnancy, comorbidity, socioeconomic deprivation, and year of delivery. We assessed whether noise exposure was more strongly associated with severe or early onset preeclampsia than mild or late onset preeclampsia.

RESULTS

Prevalence of preeclampsia was higher for women exposed to elevated environmental noise pollution levels (LA_eq24h ≥ 65 dB(A) = 37.9 per 1000 vs. <50 dB(A) = 27.9 per 1000). Compared with 50 dB(A), an LA_eq24h of 65.0 dB(A) was not significantly associated the risk of preeclampsia (OR 1.09, 95% CI 0.99-1.20). Associations were however present with severe (OR 1.29, 95% CI 1.09-1.54) and early onset (OR 1.71, 95% CI 1.20-2.43) preeclampsia, with results consistent across all noise indicators. The associations were much weaker or absent for mild and late preeclampsia.

CONCLUSIONS

Environmental noise pollution may be a novel risk factor for pregnancy-related hypertension, particularly more severe variants of preeclampsia.

Asymmetric dimethylarginine levels in preeclampsia - Systematic review and meta-analysis

OBJECTIVE

Preeclampsia (PE) is the leading cause of maternal and perinatal mortality around the world. The impaired function of fetal-placental vasculature is a key factor in PE. Several studies have investigated the connection between PE and endothelial dysfunction. Also, many authors have examined the changes in asymmetric dimethylarginine (ADMA) as a prominent marker of endothelial dysfunction. Our study aim is to review and analyse the connections between PE and ADMA levels.

METHODS

To obtain data we performed a comprehensive literature search in Pubmed, Embase and Web of Science. Standardized mean differences were used to estimate the differences in ADMA levels.

RESULTS

The quantitative analysis included 10 studies reporting a total number of 631 PE and 498 healthy pregnant individuals. We found significantly higher ADMA levels in PE patients compared to controls, when comparing the ADMA levels of the patients to the ADMA levels of the controls (z = 5.93, p < 0.001). This difference was present regardless of the measurement method. Regarding the onset of PE, we found significantly higher ADMA levels in patients suffering from early-onset PE when comparing the ADMA levels of the early-onset PE patients to that of the controls (z = 2.82, p = 0.005). However, we did not find such difference when we compared late-onset PE patients' ADMA levels to controls.

CONCLUSION

ADMA is significantly higher in PE patients than in the controls. Elevated ADMA levels can play a major role in the development of PE, but more research is needed to clarify the connection between the two.