Pre-eclampsia, the placenta and the maternal systemic inflammatory response--a review

Maternal plasma fetuin-A concentration is lower in patients who subsequently developed preterm preeclampsia than in uncomplicated pregnancy: a longitudinal study

Objective: Fetuin-A is a negative acute phase protein reactant that acts as a mediator for lipotoxicity, leading to insulin resistance. Intravascular inflammation and insulin resistance have been implicated in the mechanisms of disease responsible for preeclampsia (PE). Maternal plasma concentrations of fetuin-A at the time of diagnosis of preterm PE are lower than in control patients with a normal pregnancy outcome. However, it is unknown if the changes in maternal plasma fetuin-A concentrations precede the clinical diagnosis of the disease. We conducted a longitudinal study to determine whether patients who subsequently developed PE had a different profile of maternal plasma concentrations of fetuin-A as a function of gestational age (GA) than those with uncomplicated pregnancies. Methods: A longitudinal case-control study was performed and included 200 singleton pregnancies in the following groups: (1) patients with uncomplicated pregnancies who delivered appropriate for gestational age (AGA) neonates (n = 160); and (2) patients who subsequently developed PE (n = 40). Longitudinal samples were collected at each prenatal visit and scheduled at 4-week intervals from the first or early second trimester until delivery. Plasma fetuin-A concentrations were determined by ELISA. Analysis was performed using mixed-effects models. Results: The profiles of maternal plasma concentrations of fetuin-A differ between PE and uncomplicated pregnancies. Forward analysis indicated that the rate of increase of plasma fetuin-A concentration in patients who subsequently developed PE was lower at the beginning of pregnancy (p = 0.001), yet increased faster mid-pregnancy (p = 0.0017) and reached the same concentration level as controls by 26 weeks. The rate of decrease was higher towards the end of pregnancy in patients with PE than in uncomplicated pregnancies (p = 0.002). The mean maternal plasma fetuin-A concentration was significantly lower in patients with preterm PE at the time of clinical diagnosis than in women with uncomplicated pregnancies (p < 0.05). In contrast, there were no significant differences in maternal plasma fetuin-A concentration in patients who developed PE at term. Conclusions: (1) The profile of maternal plasma concentrations of fetuin-A over time (GA) in patients who develop PE is different from that of normal pregnant women; (2) the rate of change of maternal plasma concentrations of fetuin-A is positive (increases over time) in the midtrimester of normal pregnancy, and negative (decreases over time) in patients who subsequently develop PE; (3) at the time of diagnosis, the maternal plasma fetuin-A concentration is lower in patients with preterm PE than in those with a normal pregnancy outcome; however, such differences were not demonstrable in patients with term PE.

Interleukin-1β-31C/T and -511T/C polymorphisms were associated with preeclampsia in Chinese Han population

Objective

The purpose of our study is to investigate the relationship between IL-1β -31C/T (rs1143627) and -511T/C (rs16944) polymorphisms and the preeclampsia (PE), and analyze the Linkage disequilibrium (LD) and haplotype frequency of the two polymorphism loci.

Methods

Polymorphisms at -31C/T and -511T/C of IL-1β were genotyped with the method of polymerase chain reaction-restriction fragment length polymorphism (PCR- RFLP) in 232 PE and 447 control subjects. Genotype and allele frequencies between case-control groups were compared by chi-square(X²) tests. Two-point LD and haplotype frequency analyses were done with the software Haploview4.2.

Results

Significant statistical differences were found between PE and control groups regarding genotype and allele frequencies of the two polymorphisms of IL-1β (For IL-1β -31C/T: X² = 11.478, P = 0.003; For IL-1β-511T/C: X² = 9.687, P = 0.008). LD analysis revealed that the IL-1β -31C/T SNP was in high LD with the IL-1β-511C/T SNP(D′ = 0.92, r² = 0.79). Both CT and TC haplotypes showed significant differences between case and control groups. Only the plasma level of Prothrombin Time had a significantly statistical difference among TT, CT and CC groups of the preeclamptic two polymorphisms of IL-1β-31C/T and -511T/C (for IL-1β-31C/T, F = 1.644, P = 0.01; F = 1.587, P = 0.016).

Conclusion

Our results revealed IL-1β was associated with the PE in Chinese Han population. The CT haplotype may increase the risk of PE, while haplotype TC could be considered as a protective haplotype of PE.

Metabolomics and the great obstetrical syndromes--GDM, PET, and IUGR

Gestational diabetes mellitus, intrauterine growth restriction, and preeclamptic toxemia are common pregnancy complications that can have detrimental effects on morbidity and mortality of the mother and fetus as well as long-term health outcomes. Although they are distinct conditions, they may occur together and are often considered together as they share a common etiology of inadequate placental perfusion. The discovery and study of preventative treatments is hampered by a lack of effective screening tools to accurately identify women at the highest risk of disease. Metabolomics, an omic science, is the global quantitative assessment of endogenous metabolites within a biological system. It has proven to be a rapid approach in the identification of biomarkers predictive of the outcome of a pathological condition and the individual's response to a pharmacological treatment. We review the current and potential applications of metabolomics in maternal-fetal medicine, focusing on its use as a biomarker for great obstetrical syndromes diagnosis.

Oxidative stress-mediated aging during the fetal and perinatal periods

Oxidative stress is worldwide recognized as a fundamental component of the aging, a process that begins before birth. There is a critical balance between free radical generation and antioxidant defenses. Oxidative stress is caused by an imbalance between the production of free radicals and the ability of antioxidant system to detoxify them. Oxidative stress can occur early in pregnancy and continue in the postnatal period; this damage is implicated in the pathophysiology of pregnancy-related disorders, including recurrent pregnancy loss, preeclampsia and preterm premature rupture of membranes. Moreover, diseases of the neonatal period such as bronchopulmonary dysplasia, retinopathy of prematurity, necrotizing enterocolitis, and periventricular leukomalacia are related to free radical damage. The specific contribution of oxidative stress to the pathogenesis and progression of these neonatal diseases is only partially understood. This review summarizes what is known about the role of oxidative stress in pregnancy and in the pathogenesis of common disorders of the newborn, as a component of the early aging process.

Promoter hypomethylation and increased maspin expression in preeclamptic placentas in a Chinese population

OBJECTIVE

Preeclampsia is thought to begin with shallow trophoblast invasion and inadequate spiral artery remodeling. Maspin, a tumor-suppressor gene, plays a regulatory role in trophoblast invasion and motility. The tissue-specific methylation of the maspin promoter can regulate maspin gene expression in various cancers. We sought to detect maspin gene expression and assess the degrees of methylation of maspin promoter regions in preeclamptic placentas in the Han Chinese population and to investigate the potential role of maspin in the pathophysiology of preeclampsia.

METHODS

We conducted RT-PCR, immunohistochemistry and western blotting to characterize maspin gene expression and protein levels in the placentas from normal and preeclamptic pregnancies. Finally, using methylation-specific PCR and bisulfite sequencing PCR, we detected the degrees of methylation of the promoter regions of maspin in each of the two studied groups.

RESULTS

Maspin expression was increased at the mRNA and protein levels in the preeclamptic placentas compared to the control group. Maspin immunohistochemical staining revealed positive staining in the syncytio-cytotrophoblast layers and more diffuse staining in the preeclamptic group. The mean methylation level of the analyzed promoter region was significantly hypomethylated in the preeclamptic placentas compared to the control placentas, pointing to a negative relationship between maspin promoter methylation and gene expression.

DISCUSSION

Hypomethylation of the maspin promoter results in increased expression of maspin in preeclamptic placentas, which suggests a negative relationship between maspin methylation and maspin expression in this Han Chinese population. Thus, maspin is likely involved in the etiology of preeclampsia.

Differential activation of placental unfolded protein response pathways implies heterogeneity in causation of early- and late-onset pre-eclampsia

Based on gestational age at diagnosis and/or delivery, pre-eclampsia (PE) is commonly divided into early-onset (<34 weeks) and late-onset (≥34 weeks) forms. Recently, the distinction between ‘placental’ and ‘maternal’ causation has been proposed, with ‘placental’ cases being more frequently associated with early-onset and intrauterine growth restriction. To test whether molecular placental pathology varies according to clinical presentation, we investigated stress-signalling pathways, including unfolded protein response (UPR) pathways, MAPK stress pathways, heat-shock proteins and AMPKα in placentae delivered by caesarean section for clinical indications at different gestational ages. Controls included second-trimester, pre-term and normal-term placentae. BeWo cells were used to investigate how these pathways react to different severities of hypoxia–reoxygenation (H/R) and pro-inflammatory cytokines. Activation of placental UPR and stress-response pathways, including P-IRE1α, ATF6, XBP-1, GRP78 and GRP94, P-p38/p38 and HSP70, was higher in early-onset PE than in both late-onset PE and normotensive controls (NTCs), with a clear inflection around 34 weeks. Placentae from ≥ 34 weeks PE and NTC were indistinguishable. Levels of UPR signalling were similar between second-trimester and term controls, but were significantly higher in pre-term ‘controls’ delivered vaginally for chorioamnionitis and other conditions. Severe H/R (1/20% O₂) induced equivalent activation of UPR pathways, including P-eIF2α, ATF6, P-IRE1α, GRP78 and GRP94, in BeWo cells. By contrast, the pro-inflammatory cytokines TNFα and IL-1β induced only mild activation of P-eIF2α and GRP78. AKT, a central regulator of cell proliferation, was reduced in the < 34 weeks PE placentae and severe H/R-treated cells, but not in other conditions. These findings provide the first molecular evidence that placental stress may contribute to the pathophysiology of early-onset pre-eclampsia, whereas that is unlikely to be the case in the late-onset form of the syndrome. © 2014 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Bioinformatic approach to the genetics of preeclampsia

OBJECTIVE

To identify candidate genes and genetic variants for preeclampsia using a bioinformatic approach to extract and organize genes and variants from the published literature.

METHODS

Semantic data-mining and natural language processing were used to identify articles from the published literature meeting criteria for potential association with preeclampsia. Articles were manually reviewed by trained curators. Cluster analysis was used to aggregate the extracted genes into gene sets associated with preeclampsia or severe preeclampsia, early or late preeclampsia, maternal or fetal tissue sources, and concurrent conditions (ie, fetal growth restriction, gestational hypertension, or hemolysis, elevated liver enzymes, and low platelet count [HELLP]). Gene ontology was used to organize this large group of genes into ontology groups.

RESULTS

From more than 22 million records in PubMed, with 28,000 articles on preeclampsia, our data-mining tool identified 2,300 articles with potential genetic associations with preeclampsia-related phenotypes. After curation, 729 articles were "accepted" that contained "statistically significant" associations with 535 genes. We saw distinct segregation of these genes by severity and timing of preeclampsia, by maternal or fetal source, and with associated conditions (eg, gestational hypertension, fetal growth restriction, or HELLP syndrome).

CONCLUSION

The gene sets and ontology groups identified through our systematic literature curation indicate that preeclampsia represents several distinct phenotypes with distinct and overlapping maternal and fetal genetic contributions.

LEVEL OF EVIDENCE

III.

Expression of lipoxin A4, TNFα and IL-1β in maternal peripheral blood, umbilical cord blood and placenta, and their significance in pre-eclampsia

OBJECTIVE

The purpose of this study was to investigate the expression of lipoxin A4, TNFα and IL-1β in maternal peripheral blood, umbilical cord blood and placenta, and to assess their significance in pre-eclampsia.

METHODS

Ninty pregnant women were divided into three groups: a mild PE group (n = 30), a severe PE group (n = 30) and a control group (n = 30). We measured serum levels of lipoxin A4, TNFα and IL-1β using ELISA. Expression levels of lipoxin receptor (FPR2/ALX) mRNA were compared using quantitative RT-PCR.

RESULTS

Mean circulating levels of lipoxin A4, TNFα and IL-1β in the PE groups were significantly increased compared with matched women in the control group. The ratios of lipoxin A4/TNFα and of lipoxin A4/IL-1β in the PE groups were significantly decreased compared with matched women in the control group. No lipoxin A4 was detected in umbilical cord blood. There was a significant increase in FPR2/ALX mRNA expression in placenta obtained from the PE groups.

CONCLUSIONS

The level of lipoxin A4 in maternal peripheral blood may correlate with the expression of FPR2/ALX in placenta. Lipoxin A4 increased to a lesser degree than either TNFα or IL-1β with progression of PE. This may be one of the reasons why oxidative stress and endothelial dysfunction in severe preeclamptic patients are much more serious that in cases of less severe preeclampsia. Moreover, lipoxin A4 does not have any effect on the fetus through the placenta. We conclude that supplementing with lipoxin A4 to ensure adequate levels may be a novel method for the treatment of pre-eclampsia without any effects on the fetus.

Role of the glucose tolerance test as a predictor of preeclampsia

OBJECTIVE

To determine whether oral glucose tolerance tests (OGTT) play a role as predictors of preeclampsia (PET) in pregnant women.

METHODS

A retrospective case-control study was conducted in 2,002 singleton pregnancies that had a uterine artery (UtA) Doppler at 22-25 weeks and an OGTT. The UtA Doppler and OGTT were adjusted based on maternal characteristics, and the results were expressed as multiples of the expected normal median and compared between groups. Logistic regression analysis was used to determine whether maternal characteristics, OGTT, and UtA Doppler significantly contribute to the prediction of early- (<34 weeks), intermediate- (34-37 weeks), or late-onset (>37 weeks) PET. The performance of the screening was determined by ROC curves.

RESULTS

Women who developed PET were characterized by an older maternal age, an increased body mass index, and an altered UtA Doppler. The group with intermediate-onset PET was the only one associated with higher 2-hour OGTT levels compared to controls. Combined models were developed via logistic regression analysis using maternal characteristics, UtA Doppler, and OGTT to predict PET. These combined models were able to detect around 74, 42, and 21% of women who later developed early-, intermediate-, or late-onset PET, respectively, with only a 5% false-positive rate.

CONCLUSIONS

This study shows that the combination of maternal characteristics, second-trimester UtA Doppler, and OGTT is a predictor of the development of PET in healthy pregnant women.

Metabolomics profiling for identification of novel potential markers in early prediction of preeclampsia

Objective

The first aim was to investigate specific signature patterns of metabolites that are significantly altered in first-trimester serum of women who subsequently developed preeclampsia (PE) compared to healthy pregnancies. The second aim of this study was to examine the predictive performance of the selected metabolites for both early onset [EO-PE] and late onset PE [LO-PE].

Methods

This was a case-control study of maternal serum samples collected between 8+0 and 13+6 weeks of gestation from 167 women who subsequently developed EO-PE n = 68; LO-PE n = 99 and 500 controls with uncomplicated pregnancies. Metabolomics profiling analysis was performed using two methods. One has been optimized to target eicosanoids/oxylipins, which are known inflammation markers and the other targets compounds containing a primary or secondary biogenic amine group. Logistic regression analyses were performed to predict the development of PE using metabolites alone and in combination with first trimester mean arterial pressure (MAP) measurements.

Results

Two metabolites were significantly different between EO-PE and controls (taurine and asparagine) and one in case of LO-PE (glycylglycine). Taurine appeared the most discriminative biomarker and in combination with MAP predicted EO-PE with a detection rate (DR) of 55%, at a false-positive rate (FPR) of 10%.

Conclusion

Our findings suggest a potential role of taurine in both PE pathophysiology and first trimester screening for EO-PE.

A possible protective role of Nrf2 in preeclampsia

Excess release of reactive oxygen species (ROS) is a major cause of oxidative stress. This disturbance has been implicated as a cause of preeclampsia, a pregnancy-related disorder characterized by hypertension and proteinuria. Increased oxidative stress leads to trophoblast apoptosis/necrosis and alters the balance between pro- and anti-angiogenic factors, resulting in generalized maternal endothelial dysfunction. Trials using antioxidants have significantly failed to improve the condition of, or in any way protect, the mother from the life-threatening complications of this syndrome. Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a potent transcription activator that regulates the expression of a multitude of genes that encode detoxification enzymes and anti-oxidative proteins. Recent discussion on evidence of a link between Nrf2 and vascular angiogenic balance has focussed on the downstream target protein, heme oxygenase-1 (HO-1). HO-1 metabolizes heme to biliverdin, iron and carbon monoxide (CO). HO-1/CO protects against hypertensive cardiovascular disease and contributes to the sustained health of the vascular system. In one animal model, sFlt-1 (soluble fms-like tyrosine kinase-1) has induced blood pressure elevation, but the induction of HO-1 attenuated the hypertensive response in the pregnant animals. The special conditions under which Nrf2 participates in the pathogenesis of preeclampsia are still unclear, as is whether Nrf2 attenuates or stimulates the processes involved in this syndrome. In this review, we summarize recent theories about how Nrf2 is involved in the pathogenesis of preeclampsia and present the reasons for considering Nrf2 as a therapeutic target for the treatment of preeclampsia.

Innate immune system and preeclampsia

Normal pregnancy is considered as a Th2 type immunological state that favors an immune-tolerance environment in order to prevent fetal rejection. Preeclampsia (PE) has been classically described as a Th1/Th2 imbalance; however, the Th1/Th2 paradigm has proven insufficient to fully explain the functional and molecular changes observed during normal/pathological pregnancies. Recent studies have expanded the Th1/Th2 into a Th1/Th2/Th17 and regulatory T-cells paradigm and where dendritic cells could have a crucial role. Recently, some evidence has emerged supporting the idea that mesenchymal stem cells might be part of the feto-maternal tolerance environment. This review will discuss the involvement of the innate immune system in the establishment of a physiological environment that favors pregnancy and possible alterations related to the development of PE.

Early elevations of the complement activation fragment C3a and adverse pregnancy outcomes

OBJECTIVE

To estimate whether elevations of complement C3a early in pregnancy are predictive of the subsequent development of adverse pregnancy outcomes.

METHODS

A plasma sample was obtained from each enrolled pregnant woman before 20 weeks of gestation. The cohort (n=1,002) was evaluated for the development of adverse pregnancy outcomes defined as hypertensive diseases of pregnancy (gestational hypertension or preeclampsia), preterm birth (before 37 weeks of gestation), premature rupture of the membranes, pregnancy loss (during the embryonic and fetal period), intrauterine growth restriction, and the composite outcome of any adverse outcome.

RESULTS

One or more adverse pregnancy outcomes occurred in 211 (21%) of the cohort. The mean levels (ng/mL) of C3a in early pregnancy were significantly (P=<.001) higher among women with one or more adverse outcomes (858±435) compared with women with an uncomplicated pregnancy (741±407). Adjusted for parity and prepregnancy body mass index, women with levels of C3a in the upper quartile in early pregnancy were three times more likely to have an adverse outcome later in pregnancy compared with women in the lowest quartile (95% confidence interval, 1.8-4.8; P<.001). The link between early elevated C3a levels and adverse pregnancy outcomes was driven primarily by individual significant (P<.05) associations of C3a with hypertensive diseases of pregnancy, preterm birth, and premature rupture of the membranes.

CONCLUSION

Elevated C3a as early as the first trimester of pregnancy is an independent predictive factor for adverse pregnancy outcomes, suggesting that complement-related inflammatory events in pregnancy contribute to the subsequent development of poor outcomes at later stages of pregnancy.

LEVEL OF EVIDENCE

II.

Different levels of IL-1α, IL-6, TNF-α, NF-κB and PPAR-γ in monocyte cultures exposed by plasma preeclampsia and normotensive pregnancy

OBJECTIVE

To determine different levels of proinflammatory cytokines IL-1α, IL-6, TNF-α, nuclear NF-κB p50 and PPAR-γ in monocyte cultures exposed to normotensive pregnancy plasma compared with those exposed to preeclamptic plasma. Study design The study involved primigravidae with preeclampsia (12) and normotensive pregnancy (12) in which their blood plasma was given to monocyte cultures from isolated PBMC of healthy and non-pregnant women. They were divided into 2 groups, the first group was incubated for 24h and the second one was incubated for 48h (step 1). The levels of IL-1α, IL-6, TNF-α, and nuclear NF-κB p50 as well as PPAR-γ of both groups were subsequently measured and compared (step 2). Data were analyzed to determine the differences and interaction between both treatment groups using one-way ANOVA.

RESULTS

There was a significantly different level (p-value <0.05) of IL-1α in monocyte cultures incubated for 24h compared with those incubated for 48h, as shown in step 1 of the study. Meanwhile, step 2 of the study found significantly different levels of IL-1α, IL-6, TNF-α, and NF-κB p50 in monocyte cultures exposed to preeclamptic plasma compared with those exposed to normotensive pregnancy, in which the latter showed higher levels. Both groups also showed decreased levels of PPARγ, in which monocyte culture exposed to severe preeclamptic plasma (p value <0.05).

CONCLUSION

Preeclamptic plasma significantly increased levels of proinflammatory cytokines IL-1a, IL-6, and TNF-a in monocyte cultures. This condition was consistent with the increasing of NF-κB p50 and decreasing of PPARγ.

Altered autophagy induction by sera from pregnant women with pre-eclampsia: a case-control study

OBJECTIVE

Mechanisms leading to pre-eclampsia remain incompletely defined. Autophagy is a conserved process necessary for cell survival under adverse conditions. We hypothesised that sera from women with healthy pregnancies and women with pre-eclampsia differed in autophagy induction.

DESIGN

A case-control study.

SETTING

Weill Cornell Medical College.

POPULATION

Twenty-four normotensive pregnant women and 20 women with pre-eclampsia.

METHODS

Sera were incubated with peripheral blood mononuclear cells (PBMCs) from female donors. After 48 hours the PBMCs were lysed and the intracellular concentration of p62 was determined by enzyme-linked immunosorbent assay (ELISA). Its concentration is inversely proportional to the extent of autophagy induction. Serum endoglin, interleukin 13 (IL-13), insulin-like growth factor 1 (IGF-1), and transforming growth factor β1 (TGF-β1) levels were quantitated by ELISA.

MAIN OUTCOME MEASURES

Differences in autophagy induction and serum mediator levels in the two groups.

RESULTS

Autophagy induction increased with gestational age in sera from normotensive women (P = 0.0045), but not in women with pre-eclampsia. In the presence of an autophagy inducer, the capacity for autophagy induction decreased with gestational age in sera from women with pre-eclampsia (P = 0.0235), but not from controls. Endoglin concentrations were positively associated with the extent of autophagy induction in controls only (P = 0.0141). There was no association between autophagy and serum IL-13, IGF-1, or TGF-β1 levels.

CONCLUSIONS

Sera from women with pre-eclampsia differ from normotensive women by their inability to induce autophagy as a function of gestational age.

Fetal sex specific differences in human placentation: a prospective cohort study

INTRODUCTION

Our objective was to assess fetal sex specific differences in first trimester placental biomarkers of both physiological and pathological pregnancies and their interaction with environmental influences. This study is embedded in the Generation R Study, a prospective cohort study.

METHODS

Only live singleton births were included. Linear regression was performed to assess the effect of sex on first trimester placental biomarkers. Interaction analyses were performed to assess interaction of fetal sex with environmental influences. First trimester soluble fms-like tyrosine kinase (s-Flt1), placental growth factor (PLGF), plasminogen activator inhibitor (PAI-2) and homocysteine levels were assessed.

RESULTS

Significant fetal sex specific differences in placental biomarkers were observed. S-Flt1, PAI-2 and PLGF log transformated concentrations were 0.08 ng/mL (95% CI 0.05; 0.11), 0.07 ng/mL (95% CI 0.06; 0.09) and 0.04 pg/mL (95% CI 0.01; 0.06) higher in case of female as compared to male placentas. In pregnancies complicated by pre-eclampsia (PE), preterm birth (PTB) or a newborn being small for gestational age (SGA) no fetal sex specific differences were observed. Interaction analyses suggest that concentrations of s-Flt1, PLGF and PAI-2 decrease in male placentas in the case of hyperhomocysteinemia but remain equal in female placentas.

DISCUSSION

Fetal sex affects early placentation processes with discrepancies regarding pregnancies complicated by PE, PTB or a newborn being SGA. This suggests that other mechanisms causing these complications may dominate the fetal sex effect. The differences concerning homocysteine suggest that fetal sex dependent placental gene-environment interactions exist.

CONCLUSION

Fetal sex specific differences in placental biomarkers exist.

Decreased seizure threshold in an eclampsia-like model induced in pregnant rats with lipopolysaccharide and pentylenetetrazol treatments

Objective

Eclampsia is a poorly understood but potentially fatal complication of pregnancy. Research to date on this disorder has been hampered by the lack of a suitable animal model. To correct this deficiency, this report describes the generation of a rat eclampsia-like model using pentylenetetrazol (PTZ) in a previously established rat preeclampsia model.

Method

Rats were administered lipopolysaccharide (1.0 µg/kg) by tail vein injection on gestational day 14 to establish preeclampsia (PE). PE and control rats (non-pregnant, NP; normal-pregnant, P) were injected intraperitoneally (i.p.) with PTZ (40 mg/kg) to induce seizures. In separate experiments, MgSO₄ (270 mg/kg IP) was injected in advance of PTZ into PE rats to observe its effect on PTZ-induced seizures.

Results

PE conditions were verified in rats after LPS administration by significantly higher blood pressure (P<0.01) and urinary albumin excretion (P<0.05), elevated sFlt-1 (P<0.05) and decreased PlGF serum levels (P<0.05), and evidence of hepatic dysfunction compared to control groups. PTZ successfully induced seizure activity in all groups studied. Latency to seizure was significantly (P<0.01) less in the PE-PTZ group (73.2±6.6 sec.) than in PTZ-treated controls (107.0±7.4 sec.). Pretreatment with MgSO₄ prolonged (P<0.05) latency to seizure, shortened seizure duration and decreased seizure rates. Significant increased (P<0.05) in the serum levels of the inflammatory cytokines TNF-α and IL-1β in PE and PE-PTZ groups, and decreased (P<0.05) in their levels following MgSO₄ administration.

Conclusion

This PTZ-induced eclampsia-like rat model is comparable to the human condition of eclampsia and may serve as a useful research tool for future studies of this disease. The increased inflammatory cytokines in preeclampsia are coincident with a decreased threshold for PTZ-induced seizures, suggesting that an inflammatory mechanism may contribute to the susceptibility to seizure activity and inflammation might have an important role in eclampsia.

Evaluation of the macula, retinal nerve fiber layer and choroid in preeclampsia, healthy pregnant and healthy non-pregnant women using spectral-domain optical coherence tomography

OBJECTIVE

To evaluate the macular, retinal nerve fiber layer (RNFL) and choroidal thickness alterations by using spectral-domain optical coherence tomography (SD-OCT) in preeclampsia and compare with healthy pregnant and healthy non-pregnant controls.

METHOD

The study population included healthy pregnant control group (n: 25), healthy non-pregnant control group (n: 26) and study group with preeclampsia (n: 27). Retinal thickness parameters were measured by SD-OCT.

RESULTS

There was a statistically significant difference among all of the groups for choroidal thickness (p < 0.001). Choroidal thickness in preeclamptic women was significantly thinner than healthy pregnant women. The most thick choroid layer was detected in healthy pregnant group, and also the most thin choroidal thickness was detected in healthy non-pregnant group (p < 0.001). Macular central subfield and foveal center thickness were significantly thinner in preeclamptic study and healthy pregnant groups than healthy non-pregnant group (p < 0.001). However, there was no statistically significant difference between preeclamptic study group and healthy pregnant group for both macular central subfield and foveal center thickness. Average of RNFL thickness was significantly thicker in healthy pregnant group than healthy non-pregnant group (p = 0.004).

CONCLUSIONS

This study revealed that choroidal thickness measured using SD-OCT increased in women with preeclampsia and healthy pregnant women but the increase in choroidal thickness in preeclampsia was lower than the healthy pregnant controls. This lower rise in choroidal thickness can be generally attributed to the markedly increased systemic vascular vasospasm secondary to preeclampsia.

Recent insights into the pathophysiology of preeclampsia

Preeclampsia, characterized by new-onset gestational hypertension and proteinuria, is a common and serious complication of pregnancy. Evidence from both animal and human studies has implicated placental ischemia and hypoxia as a central causative factor in the etiology of the disorder. The ischemic placenta in turn initiates a cascade of secondary effector mechanisms, including altered proangiogenic and antiangiogenic factor balance, increase in maternal oxidative stress and endothelial and immunological dysfunction. The full elucidation of these mechanisms will hopefully lead to a more complete understanding of the etiology of preeclampsia and lead to successful therapeutic intervention through the targeted disruption of new and novel pathways.

Correlation between First and Second Trimester Uterine Artery Doppler Velocimetry and Placental Bed Histopathology

Aim. To evaluate the relationship between uterine artery Doppler indices and placental bed histopathology independent of clinical outcome. Materials and Methods. Uterine artery measurements were performed to 510 pregnant women who had come for routine antenatal care in 11–14th and 20–24th weeks. Placental bed biopsies from 141 cases were taken during cesarean section. Physiological changes and abnormal placental histology findings were investigated and compared with Doppler findings. Results. 116 biopsies were accepted as adequate biopsy and included in the study. Physiological changes were seen in 100 biopsies. Statistically significant higher PI and RI values in second trimester and higher notch rate in both trimesters were detected in the abnormal placental histology group (P < 0,001). Conclusion. Strong relationship between uterine artery Doppler indices and preeclampsia or intrauterine growth retardation has been shown in previous studies. In our study, we concluded that there is significant relationship between Doppler findings and placental bed histopathology independent of clinical course.

Reversible posterior leukoencephalopathy syndrome due to eclampsia in a woman with a twin pregnancy produced with donated oocytes

A 35-year-old primigravida with severe ovarian dysfunction underwent in vitro fertilization with oocytes donated by her sister. A twin pregnancy ensued, and she received prenatal care at our hospital. She underwent a cesarean section at 35 weeks' gestation because of pregnancy-induced hypertension (PIH) and breech presentation at the onset of labor. Eclampsia with a generalized seizure occurred 5 hours after the cesarean section, while the patient was receiving medical treatment for disseminated intravascular coagulation secondary to an atonic uterus. Reversible posterior leukoencephalopathy syndrome (RPLS) was diagnosed with magnetic resonance imaging the following day. With control of the hypertension and seizures, the condition of the patient was stabilized, and the RPLS resolved several days later. Eclampsia and RPLS associated with pregnancy can be life-threatening and are typically closely related to PIH. Thus, this case illustrates that the risk of PIH is increased in pregnancies produced with donated oocytes.

MicroRNAs: are they the missing link between hypoxia and pre-eclampsia?

Pre-eclampsia is a multisystem disorder that occurs in the second half of pregnancy affecting 5% of pregnancies. It remains the leading cause of maternal and perinatal mortality and morbidity worldwide. Impaired placental implantation, hypoxia, endothelial dysfunction and systemic inflammation are thought to have a role in the pathogenesis of pre-eclampsia. MicroRNAs (miRNAs) are short non-coding RNAs. They are important regulators of gene expression and have been found to affect cell development, proliferation, differentiation and function. Specific patterns of miRNAs have been detected in the placenta and there is altered miRNA expression in the placenta of patients with pre-eclampsia to but their role in the pathogenesis remains unclear. Furthermore, deregulated miRNAs have also been reported in human villous trophoblasts during hypoxic stress. One of the more consistently elevated miRNAs by hypoxia and in the placenta of patients with pre-eclampsia is miR-210. Whether such miRNAs are bystander markers of hypoxia, or are directly involved in the pathogenesis of pre-eclampsia, needs to be clarified. There is potential for miRNAs to be used as predictors, markers or therapy in pre-eclampsia. This review provides current knowledge about miRNAs, particularly hypoxia-related miRNAs and the interaction of hypoxia, miRNAs and placenta in pre-eclampsia.

Screening preeclamptic cord plasma for proteins associated with decreased breast cancer susceptibility

Preeclampsia, a complication of pregnancy characterized by hypertension and proteinuria, has been found to reduce the subsequent risk for breast cancer in female offspring. As this protective effect could be due to exposure to preeclampsia-specific proteins during intrauterine life, the proteomic profiles of umbilical cord blood plasma between preeclamptic and normotensive pregnancies were compared. Umbilical cord plasma samples, depleted of 14 abundant proteins, were subjected to proteomic analysis using the quantitative method of nanoACQUITY ultra performance liquid chromatography-mass spectrometry with elevated energy mode of acquisition(E) (NanoUPLC-MS(E)). Sixty-nine differentially expressed proteins were identified, of which 15 and 6 proteins were only detected in preeclamptic and normotensive pregnancies, respectively. Additionally, expression of 8 proteins (gelsolin, complement C5, keratin type I cytoskeletal 10, pigment epithelium-derived factor, complement factor B, complement component C7, hemoglobin subunit gamma-2 and alpha-fetoprotein) were up-regulated in preeclampsia with a fold change of ≥2.0 when compared to normotensive pregnancies. The identification of alpha-fetoprotein in preeclamptic umbilical cord blood plasma supported the validity of this screen as alpha-fetoprotein has anti-estrogenic properties and has previously been linked to preeclampsia as well as a reduced breast cancer risk. The findings of this pilot study may provide new insights into the mechanistic link between preeclampsia and potentially reduced breast cancer susceptibility in adult life.

Association of autoantibodies against the M2-muscarinic receptor with perinatal outcomes in women with severe preeclampsia

BACKGROUND

The goal of this study was to test the hypothesis that autoantibodies against M2-muscarinic acetylcholine receptor (M2-AAB) are associated with severe preeclampsia and increased risk of adverse perinatal outcomes.

METHODS

We conducted a case-control study comparing 60 women with severe preeclampsia to 60 women with normal pregnancy and 60 non-pregnant controls. A peptide, corresponding to amino acid sequences of the second extracellular loops of the M2 receptor, was synthesized as antigen to test for the presence of autoantibodies, using an enzyme-linked immunosorbent assay. The frequency and titer of M2-AAB were compared in the 3 groups. The risk of adverse perinatal outcomes among women with severe preeclampsia in the presence of M2-AAB was estimated.

RESULTS

M2-AAB were positive in 31.7% (19/60) of patients with severe preeclampsia, in 10.0% (6/60) (p=0.006) of normal pregnant women and in 8.3% (5/60) (p=0.002) of non-pregnant controls. The presence of M2-AAB was associated with increased risk of adverse pregnancy complications (OR, 3.6; 95%CI, 1.0-12.6; p=0.048), fetal growth restriction (OR, 6.8; 95% CI, 2.0-23.0; p=0.002), fetal distress (OR, 6.7; 95% CI, 1.7-26.6; p=0.007), low Apgar score (OR, 5.3; 95% CI, 1.4-20.7; p=0.017), and perinatal death (OR, 4.3; 95% CI, 1.0-17.6; p=0.044) among women with severe preeclampsia.

CONCLUSIONS

This study demonstrates, for the first time, an increase in M2-AAB in patients with severe preeclampsia. Women with severe preeclampsia who are M2-AAB positive are at increased risk for neonatal mortality and morbidity. We posit that M2-AAB may be involved in the pathogenesis of severe preeclampsia.

Placental leptin in HIV-associated preeclampsia

OBJECTIVE

HIV-associated preeclampsia reflects a combination of opposing influences on the immune status. The adipocyte hormone leptin has been implicated in the pathophysiology of preeclampsia and in enhancing immunity. This study is the first, to our knowledge, to determine whether leptin levels in the placenta differ between HIV-associated normotensive and preeclamptic pregnancies. The study also compares leptin levels between the exchange and conducting areas of the placenta.

STUDY DESIGN

Pregnant women were recruited antenatally and grouped as follows: normotensive HIV uninfected (n=30), normotensive HIV infected (n=60), preeclamptic HIV uninfected (n=30) and preeclamptic HIV infected (n=60). Anthropometric data were collected and placental leptin was analysed by immunohistochemistry and ELISA.

RESULTS

Leptin levels were similar in the central and peripheral regions of the placenta. Leptin immunoreactivity was observed amongst the different trophoblast cell populations. Both ELISA and immunohistochemistry of the placental exchange villi indicated that leptin levels were higher in preeclampsia compared to normotensive pregnancies (p<0.001). HIV status had no effect on leptin levels but levels were higher in participants on highly active antiretroviral treatment (HAART) compared to those on prophylaxis for prevention of mother to child transmission (PMTCT) with normotensive (p=0.006) and preeclamptic (p=0.002) pregnancies. The area of immunostaining was greater in the exchange compared to the conducting villi in HIV infected and uninfected preeclampsia.

CONCLUSIONS

This novel study establishes an elevation of leptin in preeclamptic placentae, irrespective of HIV status. Leptin elevation was not focal in that it occurred in both central and peripheral regions of the preeclamptic placenta. This suggests a role of leptin in the pathophysiology of preeclampsia.

Elevated hyaluronan and extracellular matrix metalloproteinase inducer levels in women with preeclampsia

PURPOSE

Preeclampsia (PE) is a specific syndrome of pregnancy clinically identified by hypertension and proteinuria from the 20th week of gestation associated with a systemic inflammatory response and oxidative stress. While pro-inflammatory cytokines have been extensively studied in PE, other factors in the circulation that also influence the magnitude of inflammation have received much less attention. The present study compared serum concentrations of five immune-regulatory compounds in normotensive pregnant women and in women with gestational hypertension (GH) or PE.

METHODS

Sixty women with PE, 53 with GH and 40 normotensive women paired by gestational age were evaluated. Sera were evaluated for concentrations of extracellular matrix metalloproteinase inducer (EMMPRIN), hyaluronan, gelsolin, visfatin and histone 2B by ELISA. Differences between groups were analyzed by nonparametric tests, with a significance level of 5%.

RESULTS

Increased levels of EMMPRIN and hyaluronan were present in preeclamptic women as compared to the GH and normotensive groups. There was no difference between groups in gelsolin, visfatin or histone 2B.

CONCLUSION

Increased release of EMMPRIN and hyaluronan may contribute to an elevated pro-inflammatory response and tissue damage in women with PE.

Involvement of Galectin-9/TIM-3 pathway in the systemic inflammatory response in early-onset preeclampsia

BACKGROUND

Preeclampsia is a common obstetrical disease affecting 3-5% of pregnancies and representing one of the leading causes of both maternal and fetal mortality. Maternal symptoms occur as an excessive systemic inflammatory reaction in response to the placental factors released by the oxidatively stressed and functional impaired placenta. The T-cell immunoglobulin domain and mucin domain (TIM) family is a relatively newly described group of molecules with a conserved structure and important immunological functions. Identification of Galectin-9 as a ligand for TIM-3 has established the Galectin-9/TIM-3 pathway as an important regulator of Th1 immunity and tolerance induction.

METHODS

The aim of our study was to investigate the expression and function of Galectin-9 and TIM-3 molecules by peripheral blood mononuclear cells and the possible role of Galectin-9/TIM-3 pathway in the immunoregulation of healthy pregnancy and early-onset preeclampsia. We determined TIM-3 and Gal-9 expression and cytotoxicicty of peripheral lymphocytes of early-onset preeclamptic women and healthy pregnant woman using flow cytometry.

RESULTS

Investigating peripheral lymphocytes of women with early-onset preeclampsia, our results showed a decreased TIM-3 expression by T cells, cytotoxic T cells, NK cells and CD56(dim) NK cells compared to healthy pregnant women. Interestingly, we found a notably increased frequency of Galectin-9 positive cells in each investigated lymphocyte population in the case of early-onset preeclamptic patients. We further demonstrated increased cytotoxic activity by cytotoxic T and CD56(dim) NK cells in women with early-onset preeclampsia. Our findings showed that the strongest cellular cytotoxic response of lymphocytes occurred in the TIM-3 positive subpopulations of different lymphocytes subsets in early-onset preeclampsia.

CONCLUSION

These data suggest that Gal-9/TIM-3 pathway could play an important role in the immune regulation during pregnancy and the altered Galectin-9 and TIM-3 expression could result an enhanced systemic inflammatory response including the activation of Th1 lymphocytes in preeclampsia.

Intrauterine inflammation increases materno-fetal transfer of gold nanoparticles in a size-dependent manner in murine pregnancy

The materno-fetal transfer of nanoparticles is a critical issue in designing theranoustic nanoparticles for in vivo applications during pregnancy. Recent studies have reported that certain nanoparticles can cross the placental barrier in healthy pregnant animals depending on the size and surface modification of the nanoparticles and the developmental stages of the fetuses. However, materno-fetal transfer under pathological pregnant conditions has not been examined so far. Here, it is shown that intrauterine inflammation can enhance the materno-fetal transfer of nanoparticles in the late gestation stage of murine pregnancy in a size-dependent manner. Three different-sized gold nanoparticles (Au NPs) with diameters of 3 (Au3), 13 (Au13) and 32 (Au32) nm are applied. The accumulation of Au3 and Au13 nanoparticles in the fetuses is significantly increased in intrauterine inflammatory mice compared with healthy control mice: the concentration of Au3 is much higher than Au13 in fetal tissues of intrauterine inflammatory mice. In contrast, Au32 nanoparticles cannot cross the placental barrier either in healthy or in intrauterine inflammatory mice. The possible underlying mechanism of the increased materno-fetal transfer of small-sized nanoparticles on pathological conditions is inferred to be the structural and functional abnormalities of the placenta under intrauterine inflammation. The size of the nanoparticles is one of the critical factors which determines the extent of fetal exposure to nanoparticles in murine pregnancy under inflammatory conditions.

Blood pressure rises more in pre-eclampsia than normal pregnancy when acral skin is locally cooled

OBJECTIVE

Investigate blood pressure response to acral skin vasoconstriction in healthy and pre-eclamptic pregnancies.

METHODS

Healthy women were investigated from gestational week 8 to 52 weeks postpartum and pre-eclampsia subjects at diagnosis. Finger artery ultrasound Doppler, forearm laser Doppler fluximetry and photoplethysmographic blood pressure were recorded. Hand cooling to 19 °C induced vasoconstriction.

RESULTS

Acral skin vasoconstriction increases blood pressure from 16 weeks until 12 weeks postpartum (p ≤ 0.01), with greatest responses in pre-eclampsia (p=0.047). Forearm skin perfusion is higher in pre-eclampsia (p=0.04).

CONCLUSION

Acral skin vasoconstriction raises blood pressure in pregnancy, particularly in pre-eclampsia. Pregnancy accentuates important functional differences within skin.

Umbilical artery serum chitotriosidase concentration in pregnancies complicated by preeclampsia and relationship between chitotriosidase levels and fetal blood flow velocity

OBJECTIVE

To evaluate the significance of umbilical cord chitotriosidase concentrations in pregnancies with mild preeclampsia and explore the relationship between fetal chitotriosidase levels and fetal blood flow velocity.

METHOD

The study population included control group (n=40) and study group with mild preeclampsia (n=40). Umbilical cord blood samples were collected immediately after delivery. Umbilical artery (UA) flow velocity waveform was determined just before delivery.

RESULTS

Umbilical cord chitotriosidase levels and UA S/D rate were significantly high in preeclamptic group.

CONCLUSION

Chitotriosidase may be useful biochemical marker of fetal compromise that reflects the severity of fetoplacental blood flow resistance in pregnancies complicated by preeclampsia.

A Novel ERAP2 Haplotype Structure in a Chilean Population: Implications for ERAP2 Protein Expression and Preeclampsia Risk

Single nucleotide polymorphisms (SNPs) in the endoplasmic reticulum aminopeptidase 2 (ERAP2) gene are associated with preeclampsia (PE) in different populations. rs2549782, a coding variant (N392K) that significantly affects substrate specificity, is in linkage disequilibrium (LD) with rs2248374, a marker SNP associated with ERAP2 protein expression in previously studied populations. As a result of nonsense-mediated RNA decay, ERAP2 protein is not expressed from the rs2248374 G allele. We previously reported that the fetal rs2549782 minor G allele is associated with PE in African-Americans, but not in Chileans. In this study, we found that rs2549782 was in LD with rs2248374 in African-Americans, but not in Chileans. The unexpected lack of strong LD in Chileans raised the possibility that rs2248374 could be associated with PE in the absence of an association with rs2549782. However, we found no significant association for this allele with PE in Chileans. Chileans homozygous for the rs2248374 G allele did not express 110 kDa ERAP2 protein, consistent with nonsense-mediated RNA decay, and carriers of the rs2248374 A allele did. We conclude that the Chilean ERAP2 haplotype structure allows for the expression of the major T allele of rs2549782 encoding 392N, which could impact peptide trimming and antigen presentation. Our discovery of racial differences in genetic structure and association with PE reveal heretofore unrecognized complexity of the ERAP2 locus.

Placental Vacuolar ATPase Function Is a Key Link between Multiple Causes of Preeclampsia

Preeclampsia, a relatively common pregnancy disorder, is one of the major causes of maternal and fetal morbidity and mortality. Despite numerous research, the etiology of this syndrome remains not well understood as the pathogenesis of preeclampsia is complex, involving interaction between genetic, immunologic, and environmental factors. Preeclampsia, originating in placenta abnormalities, is induced by the circulating factors derived from the abnormal placenta. Recent work has identified various molecular mechanisms related to placenta development, including renin-angiotensin system, 1, 25-dihydroxyvitamin D, and lipoxin A4. Interestingly, advances suggest that vacuolar ATPase, a key molecule in placentation, is closely associated with them. Therefore, this intriguing molecule may represent an important link between various causes of preeclampsia. Here, we review that vacuolar ATPase works as a key link between multiple causes of preeclampsia and discuss the potential molecular mechanisms. The novel findings outlined in this review may provide promising explanations for the causation of preeclampsia and a rationale for future therapeutic interventions for this condition.

Adenosine deaminase activity in normal pregnancy and pregnancy associated disorders

Adenosine deaminase (ADA) is an enzyme of purine salvage pathway and has two important isoenzymes ADA1 and ADA2. The activity of ADA has been changed in diseases characterized by altered cell-mediated immunity. It was observed that total serum ADA activity was decreased during normal pregnancy compared with non-pregnant women. However, total serum ADA activity and serum ADA2 activity was increased in hyperemesis gravidarum and pre-eclampsia in pregnant women. Less information is available regarding role of ADA in abortions (recurrent and missed) and anembryonic pregnancies. Here, we review the activity of ADA and its isoenzymes. Despite these findings, it will be interesting to know whether activity of ADA will be same if ADA is estimated throughout the pregnancy and in pregnancy related complications from early first trimester to third trimester, as all studies until now were carried out at a particular stage of pregnancy.

Association of inflammatory cytokines, lipid peroxidation end products and nitric oxide with the clinical severity and fetal outcome in preeclampsia in Indian women

Preeclampsia is a multisystem disorder associated with maternal hypertension, placental abnormalities and adverse fetal outcomes. The various pathways involved in its etiology include endothelial dysfunction, inflammatory milieu, lipid peroxidation and immunological imbalance. The present study was conducted to evaluate the causative and predictive role of nitric oxide, lipid peroxidation end products (MDA) and inflammatory cytokines (IL-6, TNF-α) in clinical presentation, severity and fetal outcome in preeclampsia. The study population was divided into 3 groups- Non- pregnant females comprising the control population; G1 and G2 groups included normal pregnant and pregnant females with preeclampsia with 50 patients in each group. Nitric Oxide and MDA levels were found to be highest in the preeclamptic patients as compared to other two groups. ROC curve analysis shows the superiority of the inflammatory markers as determinants of severity of preeclampsia which suggests the emerging role of pro inflammatory markers in the various pathological changes in preeclampsia. TNF-α emerged as the best marker in multivariate analysis and thus, has the potential for being used as a marker for PIH. Our study illustrates the multifactorial etiology of preeclampsia involving oxidative stress, proinflammatory milieu and endothelial dysfunction.

Gestational diabetes and preeclampsia in association with air pollution at levels below current air quality guidelines

BACKGROUND

Several studies have estimated associations between air pollution and birth outcomes, but few have evaluated potential effects on pregnancy complications.

OBJECTIVE

We investigated whether low-level exposure to air pollution is associated with gestational diabetes and preeclampsia.

METHODS

High-quality registry information on 81,110 singleton pregnancy outcomes in southern Sweden during 1999-2005 was linked to individual-level exposure estimates with high spatial resolution. Modeled exposure to nitrogen oxides (NOx), expressed as mean concentrations per trimester, and proximity to roads of different traffic densities were used as proxy indicators of exposure to combustion-related air pollution. The data were analyzed by logistic regression, with and without adjusting for potential confounders.

RESULTS

The prevalence of gestational diabetes increased with each NOx quartile, with an adjusted odds ratio (OR) of 1.69 (95% CI: 1.41, 2.03) for the highest (> 22.7 µg/m3) compared with the lowest quartile (2.5-8.9 µg/m3) of exposure during the second trimester. The adjusted OR for acquiring preeclampsia after exposure during the third trimester was 1.51 (1.32, 1.73) in the highest quartile of NOx compared with the lowest. Both outcomes were associated with high traffic density, but ORs were significant for gestational diabetes only.

CONCLUSION

NOx exposure during pregnancy was associated with gestational diabetes and preeclampsia in an area with air pollution levels below current air quality guidelines.

Association between the presence of autoantibodies against adrenoreceptors and severe pre-eclampsia: a pilot study

Background

Pre-eclampsia is the leading cause of maternal and neonatal morbidity and mortality with incompletely understood etiopathogenesis. The purpose of the current study is to determine whether there is a relationship between the presence of autoantibodies against β₁, β₂ and α₁ adrenoreceptors and severe pre-eclampsia.

Methodology/Principal Findings

Synthetic peptides corresponding to amino acid sequences of the second extracellular loops of β₁, β₂ and α₁ adrenoreceptors were synthesized as antigens to test 34 patients with severe pre-eclampsia, 36 normal pregnancy women and 40 non-pregnant controls for the presence of autoantibodies using enzyme-linked immunosorbent assay. The respective frequencies of autoantibodies against β₁, β₂ and α₁ adrenoreceptors were 50.0% (17/34), 52.9% (18/34) and 55.9% (19/34) in patients with severe pre-eclampsia, 19.4% (7/36) (p = 0.011), 19.4% (7/36) (p = 0.006) and 17.6% (6/36) (p = 0.001) in normal pregnancy women and 10% (4/40), 7.5% (3/40) and 10% (4/40) (p<0.001) in non-pregnant controls. Titers of these autoantibodies were also significantly increased in patients with severe pre-eclampsia. By logistic regression analysis, the presence of these three autoantibodies significantly increased the risk of neonatal death (odds ratio, 13.5; 95% confidence interval, 1.3–141.3; p = 0.030) and long-term neonatal hospitalization (odds ratio, 5.0; 95% confidence interval, 1.3–19.1; p = 0.018). The risk of hypertension and fetal distress were also associated with the presence of these three autoantibodies.

Conclusions/Significance

This novel pilot study demonstrated for the first time that the presence of autoantibodies against β₁, β₂ and α₁ adrenoreceptors are increased in patients with severe pre-eclampsia. Pregnant women who are positive for the three autoantibodies are at increased risks of neonatal mortality and morbidity. We posit that these autoantibodies may be involved in the pathogenesis of severe pre-eclampsia.

Differential expression of estradiol and estrogen receptor α in severe preeclamptic pregnancies compared with normal pregnancies

The purpose of this study was to investigate the expression of estradiol and estrogen receptor α (ESRα) in severe preeclamptic (sPE) pregnancies compared with normal pregnancies. Sera and placentas were obtained from i) patients with sPE (n=25) and ii) a normal control group (n=25) who underwent elective Cesarean deliveries. Estradiol expression was assessed by enzyme-linked immunosorbent assays (ELISAs). ESRα expression was assessed by reverse transcription polymerase chain reaction (RT-PCR) analysis and western blot analysis. In preeclamptic pregnancies, estradiol was underexpressed (P<0.05), however, ESRα mRNA and protein levels were increased significantly in comparison with normal pregnancies (P<0.05). These results show that estradiol and ESRα are deregulated in preeclamptic pregnancies, which in turn suggests the involvement of these molecules in the pathogenesis of preeclampsia.

Renal redox response to normal pregnancy in the rat

Normal pregnancy involves increased renal sodium reabsorption, metabolism, and oxygen consumption, which can cause increased oxidative stress (OS). OS can decrease nitric oxide (NO) bioavailability and cause pregnancy complications. In this study we examined the NO synthases (NOS) and redox state in the kidney cortex and aorta in early (E), mid (M), and late (L) pregnant (P) (days 3, 12, 20) and 2-4 days postpartum (PP) rats compared with virgin rats (V). Protein abundance of endothelial NOS (eNOS) was unchanged and neuronal NOS (nNOS)α fell at LP in the kidney cortex. Kidney cortex nNOSβ was elevated at MP, LP, and PP. No changes in aortic NOS isoforms were observed. Kidney cortex nitrotyrosine (NT) abundance decreased in EP, MP, and PP, whereas aortic NT increased in EP, MP, and PP. The NADPH oxidase subunit p22phox decreased in the kidney cortex at EP while aortic p22phox increased in EP and LP. No changes in kidney cortex NADPH-dependent superoxide production or hydrogen peroxide levels were noted. Kidney cortex cytosolic (CuZn) superoxide dismutase (SOD) was unchanged, while mitochondrial SOD decreased at EP and extracellular SOD decreased at MP and LP in the kidney cortex. Despite falls in abundance of kidney cortex SODs, total antioxidant capacity (TAC) was elevated in EP, MP, and PP in the kidney cortex. Aortic CuZn SOD deceased at PP, while the other aortic SODs and aortic TAC did not change. Data from this study suggest that the kidney cortex is protected from OS during normal rat pregnancy via an increase in antioxidant activity.