Markers for Presymptomatic Prediction of Preeclampsia and Intrauterine Growth Restriction

Research Progress on Extracellular Matrix Involved in the Development of Preeclampsia

Preeclampsia (PE) is a serious pregnancy complication, and its primary clinical manifestations are gestational hypertension and proteinuria. Trophoblasts are responsible for the basic functions of the placenta during placental development; recent studies have revealed that placental "shallow implantation" caused by the decreased invasiveness of placental trophoblasts plays a crucial role in PE pathogenesis. The interaction between the cells and the extracellular matrix (ECM) plays a crucial role in trophoblast proliferation, differentiation, and invasion. Abnormal ECM function can result in insufficient migration and invasion of placental trophoblasts, thus participating in PE. This article summarizes the recent studies on the involvement of ECM components, including small leucine-rich proteoglycans, syndecans, glypicans, laminins, fibronectin, collagen, and hyaluronic acid, in the development of PE. ECM plays various roles in PE development, most notably by controlling the activities of trophoblasts. The ECM is structurally stable and can serve as a biological diagnostic marker and therapeutic target for PE.

Therapeutic Potential of Targeting Prokineticin Receptors in Diseases

The prokineticins (PKs) were discovered approximately 20 years ago as small peptides inducing gut contractility. Today, they are established as angiogenic, anorectic, and proinflammatory cytokines, chemokines, hormones, and neuropeptides involved in variety of physiologic and pathophysiological pathways. Their altered expression or mutations implicated in several diseases make them a potential biomarker. Their G-protein coupled receptors, PKR1 and PKR2, have divergent roles that can be therapeutic target for treatment of cardiovascular, metabolic, and neural diseases as well as pain and cancer. This article reviews and summarizes our current knowledge of PK family functions from development of heart and brain to regulation of homeostasis in health and diseases. Finally, the review summarizes the established roles of the endogenous peptides, synthetic peptides and the selective ligands of PKR1 and PKR2, and nonpeptide orthostatic and allosteric modulator of the receptors in preclinical disease models. The present review emphasizes the ambiguous aspects and gaps in our knowledge of functions of PKR ligands and elucidates future perspectives for PK research. SIGNIFICANCE STATEMENT: This review provides an in-depth view of the prokineticin family and PK receptors that can be active without their endogenous ligand and exhibits "constitutive" activity in diseases. Their non- peptide ligands display promising effects in several preclinical disease models. PKs can be the diagnostic biomarker of several diseases. A thorough understanding of the role of prokineticin family and their receptor types in health and diseases is critical to develop novel therapeutic strategies with safety concerns.

Autophagy regulates trophoblast invasion by targeting NF-κB activity

Preeclampsia is one of the most serious complications of pregnancy, affecting 5-10% of parturients worldwide. Recent studies have suggested that autophagy is involved in trophoblast invasion and may be associated with defective placentation underlying preeclampsia. We thus aimed to understand the mechanistic link between autophagy and trophoblast invasion. Using the two most commonly used trophoblast cell lines, JEG-3 and HTR-8/SVneo, we inhibited autophagy by ATG5 and beclin-1 shRNA. Conversion of LC3-II was evaluated in ATG5 and beclin-1 knock-down cells in the presence of the lysosomal protease inhibitors E-64d and pepstatin A, to detect the efficiency of autophagy inhibition. Upon autophagy inhibition, we measured cell invasion, activity of NF-κB and related signaling pathways, MMP-2, MMP-9, sFlt-1, and TNF-α levels. Autophagy inhibition increased the invasiveness of these trophoblastic cell lines and increased Akt and NF-κB activity as well as p65 expression. Of note, an NF-κB inhibitor significantly attenuated the trophoblast invasion induced by autophagy inhibition. Autophagy inhibition was also associated with increased MMP-2 and MMP-9 levels and decreased the production of sFlt-1 and TNF-α. Collectively, our results indicate that autophagy regulates trophoblast invasiveness in which the NF-κB pathway and MMP-2, MMP-9, sFlt-1 and TNF-α levels are affected.

Association of neonatal inflammatory markers and perinatal stroke subtypes

OBJECTIVE

To examine the relationship between neonatal inflammatory cytokines and perinatal stroke using a systems biology approach analyzing serum and blood-spot cytokines from 47 patients.

METHODS

This was a population-based, controlled cohort study with prospective and retrospective case ascertainment. Participants were recruited through the Alberta Perinatal Stroke Project. Stroke was classified as neonatal arterial ischemic stroke (NAIS), arterial presumed perinatal ischemic stroke (APPIS), or periventricular venous infarction (PVI). Biosamples were stored blood spots (retrospective) and acute serum (prospective). Controls had comparable gestational and maternal ages. Sixty-five cytokines were measured (Luminex). Hierarchical clustering analysis was performed to create heat maps. The Fisher linear discriminant analysis was used to create projection models to determine discriminatory boundaries between stroke types and controls.

RESULTS

A total of 197 participants were analyzed (27 with NAIS, 8 with APPIS, 12 with PVI, 150 controls). Cytokines were quantifiable with quality control measures satisfied (standards testing, decay analysis). Linear discriminant analysis had high accuracy in using cytokine profiles to separate groups. Profiles in participants with PVI and controls were similar. NAIS separation was accurate (sensitivity 77%, specificity 97%). APPIS mapping was also distinguishable from NAIS (sensitivity 86%, specificity 99%). Classification tree analysis generated similar diagnostic accuracy.

CONCLUSIONS

Unique inflammatory biomarker signatures are associated with specific perinatal stroke diseases. Findings support an acquired pathophysiology and suggest the possibility that at-risk pregnancies might be identified to develop prevention strategies.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that differences in acute neonatal serum cytokine profiles can discriminate between patients with specific perinatal stroke diseases and controls.

Increased serum strontium levels and altered oxidative stress status in early-onset preeclampsia

BACKGROUND

Correctly distinguishing preeclampsia (PE), gestational hypertension (GH), and intrauterine growth retardation (IUGR) is a challenge for clinicians due to existing similarities. In our previous study, we showed that serum strontium (Sr) levels were elevated in preeclamptic women compared to healthy and GH pregnant women at the end of pregnancy. The main aim of this study was to evaluate Sr and oxidative stress in PE at the time of symptoms onset and before and compare it with IUGR/GH.

METHODS

Samples collected at symptoms onset included 77 preeclamptic women and 72 women diagnosed with IUGR/GH divided into two groups according to the gestational extraction week (<34 and ≥ 34). Fifteen patients were also serialized until delivery. Samples collected before symptoms onset included 140 women who developed early-onset PE (E-PE, n = 9), late-onset PE (L-PE, n = 13), IUGR (n = 9), GH (n = 32) and no pathologies (n = 77). Strontium, placental growth factor (PlGF), soluble fms-like tyrosine kinase 1 (sFlt-1), uric acid (UA), creatinine, lipid peroxidation, and total antioxidant activity (TAA) were measured.

RESULTS

Mean Sr, sFlt-1/PIGF ratio, UA, and lipid peroxidation/TAA ratio levels were significantly higher (p = 0.002, <0.0001, <0.0001 and = 0.03, respectively) and estimated glomerular filtration rate (eGFR) and TAA significantly lower (p = 0.0008 and < 0.0001, respectively) in E-PE vs other pathologies when gestational extraction week was <34. There was a significant correlation between Sr and eGFR (r = 0.43, p = 0.02), sFlt-1/PIGF ratio (r = 0.56, p = 0.002), TAA and gestational week of sampling (r = -0.45, p = 0.02) and UA (r = -0.82, p < 0.0001) in the E-PE serial samples. No differences were found in Sr levels before symptoms onset.

CONCLUSION

Serum Sr concentration and oxidative status are increased in E-PE when compared to other pathologies at the time of symptoms onset. More studies are needed to elucidate the causes of Sr levels elevation and its role in the pathophysiology of PE.

Sleep Disturbances and Modulations in Inflammation: Implications for Pregnancy Health

When a woman becomes pregnant, there is a vast series of physiological, vascular, and psychological changes. Among the most commonly reported changes are those involving sleep. Pregnant women report that their ability to maintain sleep and acquire continuous refreshing sleep is impaired during the perinatal period as compared to the non-pregnant period. A growing literature supports the hypothesis that disturbed sleep (which comes in many forms) during the perinatal period is associated with an increased risk of adverse maternal, delivery, and infant outcomes. Among the suggested biological pathways linking sleep and adverse outcomes are disturbances in the immune and hormonal systems. The following paper will discuss (1) the various sleep processes that are commonly disturbed during the perinatal period and the methods used to collect sleep data; (2) the evidence linking sleep to adverse outcomes; and (3) how one specific biological pathway, the immune system, likely mediates these associations. The goal of this paper is to clarify the role that sleep disturbance has during pregnancy.

Maternal Serum B-Cell Activating Factor Levels

Hypertensive disorders of pregnancy are a leading cause of maternal and perinatal morbidity and mortality. Early suppression of B-cell lymphopoiesis is necessary for a normal pregnancy. Dysregulation of factors critical to B-cell survival may result in pregnancy complications, including hypertension. In this prospective observational study at a single medical center, serum levels of BAFF (B-cell activating factor) were measured in pregnant participants at each trimester, at delivery, and postpartum and in nonpregnant controls at a single time point. Comparisons were made between nonpregnant and pregnant subjects and between time periods of pregnancy. First-trimester serum BAFF levels were further tested for association with hypertensive disorders of pregnancy. The study included 149 healthy pregnant women, 25 pregnant women with chronic hypertension, and 48 nonpregnant controls. Median first-trimester serum BAFF level (ng/mL) for healthy women (0.90) was lower than median serum BAFF levels for women with chronic hypertension (0.96; P =0.013) and controls (1.00; P =0.002). Serum BAFF levels steadily declined throughout pregnancy, with the median second-trimester level lower than the corresponding first-trimester level (0.77; P =0.003) and the median third-trimester level lower than the corresponding second-trimester level (0.72; P =0.025). The median first-trimester serum BAFF level was elevated in women who subsequently developed hypertension compared with women who remained normotensive (1.02 versus 0.85; P =0.012), with the area under the receiver operating characteristic curve being 0.709. First-trimester serum BAFF level may be an early and clinically useful predictor of hypertensive disorders of pregnancy.

Cell-Free Total and Fetal DNA in First Trimester Maternal Serum and Subsequent Development of Preeclampsia

Objective The objective of this study was to assess the relationship between first trimester cell-free total and fetal DNA in maternal plasma and the subsequent development of preeclampsia. Study Design Nested case-control study of patients enrolled in the Combined Antioxidant and Preeclampsia Prediction Studies prediction study of 175 women who did and 175 women who did not develop preeclampsia. The predictive values of cell-free total and fetal DNA and the subsequent development of preeclampsia were measured using receiver operating characteristic curves. Results Cell-free total DNA was higher in African American (median; 25-75%; 6.15; 0.14-28.73; p = 0.02) and Hispanic (4.95; 0.20-26.82; p = 0.037) compared with white women (2.33; 0.03-13.10). Levels of cell-free total DNA were also associated with maternal body mass index (BMI) (p = 0.02). Cell-free total DNA levels were similar between women who later developed preeclampsia (3.52; 0.11-25.3) and controls (3.74; 0.12-21.14, p = 0.96). Conclusion There is no significant difference in levels of cell-free total DNA in the first trimester in women who subsequently develop preeclampsia. Levels of cell-free total DNA in the first trimester are increased in African American and Hispanic compared with white women, and levels increase with increasing BMI.

Utility of a single mid-trimester measurement of plasminogen activator Type 1 and fibronectin to predict preeclampsia in pregnancy

BACKGROUND

Preeclampsia (PE) is the second most common cause of maternal death after obstetric hemorrhage in Africa, a resource-limited region. This study was designed to examine the potential usefulness of a single screening plasma plasminogen activator inhibitor-1 (PAI-1) and fibronectin (FN) level for the prediction of PE in pregnant women.

MATERIALS AND METHODS

In a cohort of 180 pregnant women who were normotensive at baseline, venous blood samples were obtained before 20 weeks of gestation for the assay of plasma levels of PAI-1 and FN levels measured by enzyme-linked immunoassay technique. Twenty nonpregnant normotensive women were also evaluated as a control group. Outcomes of gestation were evaluated and correlated with the plasma levels of PAI and FN measured at mid-trimester. Mean plasma values of PAI-1 and FN were also compared between the different outcome groups.

RESULTS

Plasma PAI-1 level was significantly higher in the pregnant women (8.68 ± 0.56 ng/ml) than in nonpregnant controls (5.55 ± 0.32 ng/ml) (P = 0.01). However, plasma FN did not show any significant difference in pregnant women (2.60 ± 0.37 μg/ml) and nonpregnant controls (2.60 ± 0.23 μg/ml) (P = 0.9). Mid-trimester mean plasma PAI-1 level measured in women who developed PE (7.08 ± 5.49 ng/ml, n = 12) and gestational hypertension (GH) (9.78 ± 6.2 ng/ml, n = 13) was not significantly different in comparison to normotensive pregnant women (8.78 ± 5.63 ng/ml, n = 153) (P = 0.75). Likewise, the mean FN level in women who developed PE was also not significantly different from nonpreeclamptics; however, the FN level in the pregnant women who developed GH was significantly different from women who remained normotensive throughout pregnancy (P = 0.02).

CONCLUSION

Single mid-trimester assessment of PAI-1 and FN levels in maternal plasma was not found to be useful in predicting PE as an outcome of pregnancy in the study population.

Abnormal expression of inflammatory genes in placentas of women with sickle cell anemia and sickle hemoglobin C disease

Sickle cell disease (SCD) is a complex disease that is characterized by the polymerization of deoxyhemoglobin S, altered red blood cell membrane biology, endothelial activation, hemolysis, a procoagulant state, acute and chronic inflammation, and vaso-occlusion. Among the physiological changes that occur during pregnancy, oxygen is consumed by fetal growth, and pregnant women with SCD are more frequently exposed to low oxygen levels. This might lead to red blood cells sickling, and, consequently, to vaso-occlusion. The mechanisms by which SCD affects placental physiology are largely unknown, and chronic inflammation might be involved in this process. This study aimed to evaluate the gene expression profile of inflammatory response mediators in the placentas of pregnant women with sickle cell cell anemia (HbSS) and hemoglobinopathy SC (HbSC). Our results show differences in a number of these genes. For the HbSS group, when compared to the control group, the following genes showed differential expression: IL1RAP (2.76-fold), BCL6 (4.49-fold), CXCL10 (-2.12-fold), CXCR1 (-3.66-fold), and C3 (-2.0-fold). On the other hand, the HbSC group presented differential expressions of the following genes, when compared to the control group: IL1RAP (4.33-fold), CXCL1 (3.05-fold), BCL6 (4.13-fold), CXCL10 (-3.32-fold), C3 (-2.0-fold), and TLR3 (2.38-fold). Taken together, these data strongly suggest a differential expression of several inflammatory genes in both SCD (HbSS and HbSC), indicating that the placenta might become an environment with hypoxia, and increased inflammation, which could lead to improper placental development.

Ischemic placental syndrome--prediction and new disease monitoring

The last decade has seen an improved understanding of the cause of the development of pathologies such as gestational hypertension, preeclampsia, intrauterine growth restriction, intrauterine fetal death or placental abruption. Nowadays, we know that most conditions within this group share the same pathogenesis, the cause of which is placental ischemia. The following review is an attempt to propose a new method for prediction, diagnosis and--above all--appropriate monitoring of pregnant women and fetuses developing the ischemic placental syndrome with the use of tests that are new but yet widely available in clinical diagnosis. They are closely related to the condition's pathogenesis, therefore their elevated levels may predate clinical symptoms, and--most importantly--they correlate with syndrome aggravation and the occurrence of complications. Perhaps, the new look will allow us to improve perinatal results by reducing mortality and severe complications in pregnant women and fetal deaths resulting from sudden intrauterine fetal death or placental abruption.

Tetrabromobisphenol A activates inflammatory pathways in human first trimester extravillous trophoblasts in vitro

Tetrabromobisphenol A (TBBPA) is a widely used flame retardant. Despite the presence of TBBPA in gestational tissues and the importance of proper regulation of inflammatory networks for successful pregnancy, there is no prior study on the effects of TBBPA on inflammatory responses in gestational tissues. The present study aimed to investigate TBBPA activation of inflammatory pathways, specifically cytokine and prostaglandin production, in the human first trimester placental cell line HTR-8/SVneo. TBBPA enhanced release of interleukin (IL)-6, IL-8, and prostaglandin E2 (PGE2), and suppressed TGF-β release in HTR-8/SVneo cells. The lowest effective concentration was 10 μM TBBPA. A commercial immune response PCR array revealed increased expression of genes involved in inflammatory pathways stimulated by TBBPA in HTR-8/SVneo cells. Because proper regulation of inflammatory mediators in the gestational compartment is necessary for normal placental development and successful pregnancy, further investigation on the impact of TBBPA-stimulated responses on trophoblast function is warranted.

Protective effect of nuclear factor E2-related factor 2 on inflammatory cytokine response to brominated diphenyl ether-47 in the HTR-8/SVneo human first trimester extravillous trophoblast cell line

Polybrominated diphenyl ethers (PBDEs) are widely used flame retardants, and BDE-47 is a prevalent PBDE congener detected in human tissues. Exposure to PBDEs has been linked to adverse pregnancy outcomes in humans. Although the underlying mechanisms of adverse birth outcomes are poorly understood, critical roles for oxidative stress and inflammation are implicated. The present study investigated antioxidant responses in a human extravillous trophoblast cell line, HTR-8/SVneo, and examined the role of nuclear factor E2-related factor 2 (Nrf2), an antioxidative transcription factor, in BDE-47-induced inflammatory responses in the cells. Treatment of HTR-8/SVneo cells with 5, 10, 15, and 20μM BDE-47 for 24h increased intracellular glutathione (GSH) levels compared to solvent control. Treatment of HTR-8/SVneo cells with 20μM BDE-47 for 24h induced the antioxidant response element (ARE) activity, indicating Nrf2 transactivation by BDE-47 treatment, and resulted in differential expression of redox-sensitive genes compared to solvent control. Pretreatment with tert-butyl hydroquinone (tBHQ) or sulforaphane, known Nrf2 inducers, reduced BDE-47-stimulated IL-6 release with increased ARE reporter activity, reduced nuclear factor kappa B (NF-κB) reporter activity, increased GSH production, and stimulated expression of antioxidant genes compared to non-Nrf2 inducer pretreated groups, suggesting that Nrf2 may play a protective role against BDE-47-mediated inflammatory responses in HTR-8/SVneo cells. These results suggest that Nrf2 activation significantly attenuated BDE-47-induced IL-6 release by augmentation of cellular antioxidative system via upregulation of Nrf2 signaling pathways, and that Nrf2 induction may be a potential therapeutic target to reduce adverse pregnancy outcomes associated with toxicant-induced oxidative stress and inflammation.

Placental maturity, hypertensive disorders of pregnancy and birth weight

OBJECTIVES

To compare maturity of placentas from women with hypertensive disorders with those from normotensive pregnancies and to determine the relationship between placental maturity (PM) and the diagnosis of small-for-gestational-age (SGA) in the newborns.

MATERIALS AND METHODS

We examined placental stained specimens from women with normotensive pregnancies (n = 100), diagnosis of gestational hypertension (n = 38), mild (n = 10), or severe preeclampsia (n = 34) in an optical microscope. Placental Maturity Index (PMI) was calculated as the number of vasculo-syncytial membranes (VSM) in 1 mm(2) divided by VSM thickness (µm). Hypermaturity was defined as >90th percentile of the PMI from placentas of normotensive pregnancies. Newborns were classified as SGA, adequate-for-gestational-age (AGA) or large-for-gestational-age (<10th, 10-90th, and >90th percentile from weight for gestational age reference tables, respectively).

RESULTS

PMI in preeclamptic women (taking together mild and severe preeclampsia, PMI = 43.4 ± 1.6) was significantly higher than in normotensive women (PMI = 36 ± 2, p = 0.045). Hypermaturity was more frequent (p < 0.05) in placentas from women with preeclampsia than in those from normotensive women only in preterm pregnancies (<37 weeks), but not in those at term (p = 0.41). The frequency of hypermaturity in placentas from women with gestational hypertension was not statistically different than in normotensive women. Hypermaturity was also more frequent in placentas from SGA (OR = 2.63, p < 0.05) than in AGA newborns.

CONCLUSION

The PMI was increased in preeclampsia, but not in gestational hypertension. Placental hypermaturity was also associated with the diagnosis of SGA in newborns. PM might have a role in the relationship between maternal factors and SGA.

Umbilical Vein and Maternal Serum Inhibin A, Activin A, and Follistatin Concentrations in IUGR due to Placental Dysfunction Pregnancies

OBJECTIVE

The objective of this study were to (1) quantify the concentrations of inhibin A, activin A, and follistatin in maternal serum and umbilical vein (inhibin A, activin A) in IUGR due to placental dysfunction pregnancies and control group, (2) determine the concentration differences of these factors in maternal and umbilical vein serum in control and subject group, and (3) examine the relationship between fetal growth and placental function.

METHOD

Sandwich ELISA was used to measure the concentrations in control (n = 40) and subject groups (n = 30).

RESULTS

Umbilical vein serum inhibin A, activin A concentrations were increased in subject group compared with controls (inhibin A regression coefficient, 0.7647, P < 0.001, activin A P < 0.0005). Maternal serum inhibin A, activin A were significantly increased in subject group compared with controls (inhibin A regression coefficient, 0.7614, P < 0.001, activin A P < 0.0005). Maternal serum activin: follistatin ratio was significantly increased in subject group compared with controls (P < 0.0005). Maternal serum inhibin A, activin A concentrations were more when compared to the umbilical vein inhibin A, activin A concentrations in subject group.

CONCLUSION

The present study strengthens the evidence of using inhibin A, activin A, and follistatin as serum markers in routine screening for early detection of IUGR. But large prospective studies are needed to further define their role in clinical practice.

Non-coding RNA and DNA as epigenetic biomarkers for pre-eclampsia

The human genome contains a hidden and large layer of biologic information that is not accessible by proteomic or metabolic methods. Insight into the nature, size, function and importance of this information is increasing rapidly. This additional layer of information includes non-coding RNA and DNA and can be retrieved and analyzed using nucleic acids that circulate in the maternal plasma during pregnancy, originate from the developing placenta and provide information on fetal well being. This review explains why, when and how fetal information as carried on and provided by the placental DNA and RNA molecules circulating in the plasma of pregnant women can be explored to understand and to analyze the primary placental processes, that underlie pre-eclampsia and related disorders.

Novel biomarkers for predicting intrauterine growth restriction: a systematic review and meta-analysis

BACKGROUND

Several biomarkers for predicting intrauterine growth restriction (IUGR) have been proposed in recent years. However, the predictive performance of these biomarkers has not been systematically evaluated.

OBJECTIVE

To determine the predictive accuracy of novel biomarkers for IUGR in women with singleton gestations.

SEARCH STRATEGY

Electronic databases, reference list checking and conference proceedings.

SELECTION CRITERIA

Observational studies that evaluated the accuracy of novel biomarkers proposed for predicting IUGR.

DATA COLLECTION AND ANALYSIS

Data were extracted on characteristics, quality and predictive accuracy from each study to construct 2×2 tables. Summary receiver operating characteristic curves, sensitivities, specificities and likelihood ratios (LRs) were generated.

MAIN RESULTS

A total of 53 studies, including 39,974 women and evaluating 37 novel biomarkers, fulfilled the inclusion criteria. Overall, the predictive accuracy of angiogenic factors for IUGR was minimal (median pooled positive and negative LRs of 1.7, range 1.0-19.8; and 0.8, range 0.0-1.0, respectively). Two small case-control studies reported high predictive values for placental growth factor and angiopoietin-2 only when IUGR was defined as birthweight centile with clinical or pathological evidence of fetal growth restriction. Biomarkers related to endothelial function/oxidative stress, placental protein/hormone, and others such as serum levels of vitamin D, urinary albumin:creatinine ratio, thyroid function tests and metabolomic profile had low predictive accuracy.

CONCLUSIONS

None of the novel biomarkers evaluated in this review are sufficiently accurate to recommend their use as predictors of IUGR in routine clinical practice. However, the use of biomarkers in combination with biophysical parameters and maternal characteristics could be more useful and merits further research.

Linking preeclampsia and cardiovascular disease later in life

Preeclampsia (PE), which is defined as new onset hypertension after 20 weeks of pregnancy accompanied by proteinuria, is characterized by inadequate placentation, oxidative stress, inflammation and widespread endothelial dysfunction. A link between PE and long-term risk of cardiovascular disease (CVD) was suggested by retrospective studies, which found that PE was associated with a 2–3-fold risk of CVD later in life, with a 5–7-fold risk in the case of severe and/or early-onset PE. Recently, meta-analyses and prospective studies have confirmed the association between PE and the emergence of an unfavorable CVD risk profile, in particular a 3–5-fold increased prevalence of the metabolic syndrome only 8 years after the index pregnancy. PE and CVD share many risk factors, including obesity, hypertension, dyslipidemia, hypercoagulability, insulin resistance and both entities are characterized by endothelial dysfunction. PE and CVD are complex traits sharing common risk factors and pathophysiological processes, but the genetic link between both remains to be elucidated. However, recent evidence suggests that genetic determinants associated with the metabolic syndrome, inflammation and subsequent endothelial dysfunction are involved. As the evidence now supports that PE represents a risk factor for the emergence of the metabolic syndrome and CVD later in life, the importance of long-term follow-up assessment of CVD risk beginning early in women with a history of PE must be considered and translated into new preventive measures.

Hypertensive disorders of pregnancy: preventative-, immediate- and long-term management

The hypertensive disorders of pregnancy are common and continue to be significant contributors to maternal and perinatal mortality and morbidity, both globally and in the UK. This review aims to describe the recent developments in the understanding of the pathophysiology of the disease processes, potential strategies for identification of women at high risk, and current and future therapeutic strategies for the treatment and prevention of hypertension in pregnancy. Women who experience adverse pregnancy outcomes are also at increased risk of premature cardiovascular disease, and potential therapeutic strategies to minimize their risk profile are discussed.

Proteomic biomarkers in second trimester amniotic fluid that identify women who are destined to develop preeclampsia

OBJECTIVES

This study investigated whether proteomic analysis of amniotic fluid (AF) in the early second trimester can be used to predict the development of preeclampsia.

METHODS

Amniotic fluid samples were collected at the time of genetic amniocentesis (15-19 weeks of gestation) from women who subsequently developed preeclampsia and from gestational age-matched normotensive controls (n = 10 for each). Amniotic fluid samples were subjected to proteomic analysis using surface-enhanced laser desorption/ionization time-of-flight mass spectrometry, sodium dodecyl sulfate polyacrylamide gel coupled with in-gel tryptic digestion, electrospray ionization tandem mass spectrometry (MS/MS), immunodepletion assays, and enzyme-linke immunosorbent assay.

RESULTS

Five proteomic biomarkers were identified, which were differentially expressed in women who subsequently developed preeclampsia compared with those women who did not; four of these peaks were significantly upregulated (mass-to-charge ratio of 9080 [P = .006], 14 045 [P = .010], 14 345 [P = .049], and 28 087 [P = .006]) and one was significantly downregulated (mass-to-charge ratio of 4679 [P = .014]) in women who subsequently developed preeclampsia. Using electrospray ionization MS/MS and immunodepletion assays, two protein peaks were identified as albumin fragment and apolipoprotein A-I.

CONCLUSIONS

Using proteomic technology, this study identified protein biomarkers that are differentially expressed in the early second trimester AF from women who subsequently develop preeclampsia compared with women who remained normotensive. Early identification of women at risk of developing preeclampsia will allow clinicians to better optimize maternal and perinatal outcomes.

Decidual-secreted factors alter invasive trophoblast membrane and secreted proteins implying a role for decidual cell regulation of placentation

Inadequate or inappropriate implantation and placentation during the establishment of human pregnancy is thought to lead to first trimester miscarriage, placental insufficiency and other obstetric complications. To create the placental blood supply, specialized cells, the ‘extravillous trophoblast’ (EVT) invade through the differentiated uterine endometrium (the decidua) to engraft and remodel uterine spiral arteries. We hypothesized that decidual factors would regulate EVT function by altering the production of EVT membrane and secreted factors. We used a proteomics approach to identify EVT membrane and secreted proteins regulated by decidual cell factors. Human endometrial stromal cells were decidualized in vitro by treatment with estradiol (10⁻⁸ M), medroxyprogesterone acetate (10⁻⁷ M) and cAMP (0.5 mM) for 14 days. Conditioned media (CM) was collected on day 2 (non-decidualized CM) and 14 (decidualized CM) of treatment. Isolated primary EVT cultured on Matrigel™ were treated with media control, non-decidualized or decidualized CM for 16 h. EVT CM was fractionated for proteins <30 kDa using size-exclusion affinity nanoparticles (SEAN) before trypsin digestion and HPLC-MS/MS. 43 proteins produced by EVT were identified; 14 not previously known to be expressed in the placenta and 12 which had previously been associated with diseases of pregnancy including preeclampsia. Profilin 1, lysosome associated membrane glycoprotein 1 (LAMP1), dipeptidyl peptidase 1 (DPP1/cathepsin C) and annexin A2 expression by interstitial EVT in vivo was validated by immunhistochemistry. Decidual CM regulation in vitro was validated by western blotting: decidualized CM upregulated profilin 1 in EVT CM and non-decidualized CM upregulated annexin A2 in EVT CM and pro-DPP1 in EVT cell lysate. Here, non-decidualized factors induced protease expression by EVT suggesting that non-decidualized factors may induce a pro-inflammatory cascade. Preeclampsia is a pro-inflammatory condition. Overall, we have demonstrated the potential of a proteomics approach to identify novel proteins expressed by EVT and to uncover the mechanisms leading to disease states.

Lipopolysaccharide induces cytokine production and decreases extravillous trophoblast invasion through a mitogen-activated protein kinase-mediated pathway: possible mechanisms of first trimester placental dysfunction

BACKGROUND

Defects in extravillous trophoblast (EVT) function could contribute to placental dysfunction resulting in adverse obstetrical outcomes. Adverse obstetrical outcomes have been highly correlated with intrauterine infection; however, the mechanisms linking infection to placental dysfunction remain unclear. We investigated the effects of inflammation on EVT cytokine production and invasion early in pregnancy and determined the cell signaling pathways mediating this response.

METHODS AND RESULTS

In our model of inflammation, EVT cells, isolated following first trimester pregnancy terminations (n= 6) were stimulated with lipopolysaccharide (LPS). LPS induced a dose-dependent increase in interleukin (IL)-8 and IL-6 protein production (P < 0.01) and decreased EVT invasion (P = 0.01) versus control. The LPS-mediated changes in cytokine production (P < 0.001) and invasion (P < 0.001) were reversed by dexamethasone (DEX). Exposure to LPS resulted in an increase in mitogen-activated protein kinase (MAPK) signaling pathway phosphorylation, including p44/42 MAPK (P < 0.01), p38 MAPK (P < 0.05), MAPK extracellular signal-regulated kinase 1/2 (MEK1/2) (P< 0.01) and stress-activated protein kinase/c-Jun N-terminal kinase (JNK; P < 0.001), which was reversed by DEX (P < 0.05) for all MAPKs except p38. MAPK-specific inhibitors to MEK1/2 (U0126), p38 MAPK (SB 202190) and JNK (SP 600125) significantly reversed the LPS-mediated increase in IL-6 (P < 0.001) and IL-8 (P < 0.001) production. While U0126 reversed the LPS-induced decrease in EVT invasion (P < 0.001), SB 202190 (P < 0.001) and SP 600125 (P< 0.001) decreased EVT invasion, further indicating that MEK1/2 phosphorylation may be inflammation dependent while p38 MAPK and JNK phosphorylation occurs independently of an inflammatory stimulus.

CONCLUSIONS

LPS increased IL-8 and IL-6 and decreased EVT invasion through activation of MAPK signaling. MEK1/2 activation may contribute to placental dysfunction, in the setting of inflammation-associated adverse obstetrical outcomes.

Early biometric lag in the prediction of small for gestational age neonates and preeclampsia

OBJECTIVE

An early fetal growth lag may be a marker of future complications. We sought to determine the utility of early biometric variables in predicting adverse pregnancy outcomes.

METHODS

In this retrospective cohort study, the crown-rump length at 11 to 14 weeks and the head circumference, biparietal diameter, abdominal circumference, femur length, humerus length, transverse cerebellar diameter, and estimated fetal weight at 18 to 24 weeks were converted to an estimated gestational age using published regression formulas. Sonographic fetal growth (difference between each biometric gestational age and the crown-rump length gestational age) minus expected fetal growth (number of days elapsed between the two scans) yielded the biometric growth lag. These lags were tested as predictors of small for gestational age (SGA) neonates (≤10th percentile) and preeclampsia.

RESULTS

A total of 245 patients were included. Thirty-two (13.1%) delivered an SGA neonate, and 43 (17.6%) had the composite outcome. The head circumference, biparietal diameter, abdominal circumference, and estimated fetal weight lags were identified as significant predictors of SGA neonates after adjusted analyses (P < .05). The addition of either the estimated fetal weight or abdominal circumference lag to maternal characteristics alone significantly improved the performance of the predictive model, achieving areas under the curve of 0.72 and 0.74, respectively. No significant association was found between the biometric lag variables and the development of preeclampsia.

CONCLUSIONS

Routinely available biometric data can be used to improve the prediction of adverse outcomes such as SGA. These biometric lags should be considered in efforts to develop screening algorithms for adverse outcomes.

[Predictive index for preeclampsia before conception and primary prevention]

OBJECTIVE

To derive a prediction index based on the most salient history, laboratory and clinical parameters for identifying women at high risk of developing preeclampsia (PE) and to suggest a primary prevention.

MATERIAL AND METHOD

Non-pregnant women with a history of PE (n=101) were compared to non-pregnant parous women with a history of one or more successful normotensive pregnancies (n=50) but with comparable age, gestation and parity profiles. The parameters included history and clinical examination; laboratory studies (hemostasis, coagulation, vitamins); and morphological and functional tests (cardiovascular and renal functions). Stepwise logistic regression analysis was applied to develop a three step PE prediction index based on the most discriminant parameters. Strategies to prevent PE in the high-risk group are described.

RESULTS

Identification of women at high risk of PE can be done efficiently (88% sensitivity and specificity) using a predictive index based on a simple history, laboratory, clinical and functional information. Strategies to prevent PE in our high-risk group have given encouraging results during next pregnancy.

CONCLUSION

Our study gives a predictive index of PE outside of pregnancy and possibilities to do a primary prevention.

Assessment of proteinuria in pregnancy

Urinary spot protein:creatinine ratio can reliably rule out proteinuria in pregnancy

Non-invasive prenatal diagnosis: implications for antenatal diagnosis and management of high-risk pregnancies

There has been a huge effort in the last 2-3 decades to develop non-invasive prenatal diagnosis to avoid the risks to the fetus caused by invasive procedures. Obtaining fetal nucleic material for molecular analysis without the need of invasive procedures has been a goal of prenatal diagnosis for many years; this is now been made possible by the use of non-cellular fetal nucleic acids circulating in maternal blood. The placenta is the primary source of these nucleic acids, raising the possibility that they could be a marker for pregnancy complications resulting from placental disease/dysfunction such as pre-eclampsia and fetal growth restriction. If so, these markers might be able to identify cases at risk, predict disease and/or its severity or allow early diagnosis. This has the potential to allow improvements in the management of complicated pregnancies.

Prediction and perinatal outcomes of fetal growth restriction

Assessment of fetal growth and wellbeing is one of the major purposes of antenatal care. Some fetuses have smaller than expected growth in utero and while some of these fetuses are constitutionally small, others have failed to meet their growth potential, that is they are growth restricted. While severe growth restriction is uncommon, the consequences of it being undetected may include perinatal death or severe morbidity. It is, therefore, important to have strategies in place to detect the fetus at risk of growth restriction. These would include an assessment of 'prior risk' from maternal history and examination combined with the results of biochemical and ultrasound investigations, the most promising of which are uterine artery Doppler and biochemistry. We discuss some of the factors to consider when stratifying the obstetric population into degrees of likelihood for growth restriction, and discuss aspects of the management and outcome of pregnancies complicated by growth restriction.

Circulating angiogenic factors in early pregnancy and the risk of preeclampsia, intrauterine growth restriction, spontaneous preterm birth, and stillbirth

OBJECTIVE

To estimate the relationship between maternal serum levels of placental growth factor (PlGF) and soluble fms-like tyrosine kinase-1 (sFlt-1) in early pregnancy with the risk of subsequent adverse outcome.

METHODS

A nested, case-control study was performed within a prospective cohort study of Down syndrome screening. Maternal serum levels of sFlt-1 and PlGF at 10-14 weeks of gestation were compared between 939 women with complicated pregnancies and 937 controls. Associations were quantified as the odds ratio for a one decile increase in the corrected level of the analyte.

RESULTS

Higher levels of sFlt-1 were not associated with the risk of preeclampsia but were associated with a reduced risk of delivery of a small for gestational age infant (odds ratio [OR] 0.92, 95% confidence interval [CI] 0.88-0.96), extreme (24-32 weeks) spontaneous preterm birth (OR 0.90, 95% CI 0.83-0.99), moderate (33-36 weeks) spontaneous preterm birth (OR 0.93, 95% CI 0.88-0.98), and stillbirth associated with abruption or growth restriction (OR 0.77, 95% CI 0.61-0.95). Higher levels of PlGF were associated with a reduced risk of preeclampsia (OR 0.95, 95% CI 0.90-0.99) and delivery of a small for gestational age infant (OR 0.95, 95% CI 0.91-0.99). Associations were minimally affected by adjustment for maternal characteristics.

CONCLUSION

Higher early pregnancy levels of sFlt-1 and PlGF were associated with a decreased risk of adverse perinatal outcome.

Investigation of endothelin-1 type A receptor gene polymorphism (-231 G > A) in preeclampsia susceptibility

OBJECTIVE

Preeclampsia is considered as a multifactorial disorder with a genetic predisposition. Alterations in the endothelin-1 (ET-1) system are considered to take part in triggering the vasoconstriction seen in preeclampsia.

METHODS

In order to investigate the possible association of the -231 G > A polymorphism in the endothelin-1 type A receptor gene (EDNRA), previously shown to be associated with other conditions characterized by vasospasm, we examined 77 Caucasian preeclamptic women and 67 matched controls including normotensive subjects without history of thromboembolic event, abnormalities in blood pressure, proteinuria, edema and preeclampsia. The genotype was assessed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) on genomic DNA extracted from blood samples. Case vs. control allele frequencies and genotype distributions were compared.

RESULTS

No significant differences were found when considering both genotype (chi(2) = 0.58, p = 0.75) and allelic frequencies (chi(2) = 0.08, p = 0.77). Furthermore, no significant genotype-related difference was found in relation to clinical features, such as gestational age at onset, systolic and diastolic blood pressure, proteinuria on admission and delivery week.

CONCLUSIONS

No association between the -231 G > A polymorphism in the EDNRA gene and preeclampsia as well as any correlation with the main clinical features of the disorder were found, thus excluding a role for this polymorphism in susceptibility to preeclampsia.

Gabor Than Award Lecture 2006: pre-eclampsia and villous trophoblast turnover: perspectives and possibilities

Placental apoptosis is exaggerated in pre-eclampsia and cytotrophoblast proliferation is enhanced. This imbalance may be a primary pathogenic event, whereby excessive syncytiotrophoblast apoptosis counters cytotrophoblast fusion, promoting the liberation of syncytial material which perturbs the maternal vascular endothelium. We have previously shown that primary trophoblasts and explant cultured villous fragments from pre-eclamptic pregnancies elicit greater levels of terminal differentiation and apoptosis. This review considers current opinions in trophoblast cell turnover in normal pregnancy and pre-eclampsia. In the context of other findings, this review highlights: (i) the disparity in expression of pro-apoptotic transcription factor p53 in the syncytiotrophoblast in pre-eclampsia, (ii) the importance of reactive oxygen species and hypoxia in initiating villous trophoblast apoptosis and (iii) the concept that aberrant intervillous haemodynamics, as opposed to oxygen per se, initiates excessive syncytiotrophoblast shedding. Finally, therapeutic ways of restoring the syncytiotrophoblast in pre-eclampsia and preventing excessive placental apoptosis are considered, including a role for mitotic manipulators and growth factor replacement strategies.

Control of human trophoblast function

The trophoblast, i.e. the peripheral part of the human conceptus, exerts a crucial role in implantation and placentation. Both processes properly occur as a consequence of an intimate dialogue between fetal and maternal tissues, fulfilled by membrane ligands and receptors, as well as by hormone and local factor release. During blastocyst implantation, generation of distinct trophoblast cell types begins, namely the villous and the extravillous trophoblast, the former of which is devoted to fetal-maternal exchanges and the latter binds the placental body to the uterine wall. Physiological placentation is characterized by the invasion of the uterine spiral arteries by extravillous trophoblast cells arising from anchoring villi. Due to this invasion, the arterial structure is replaced by amorphous fibrinoid material and endovascular trophoblastic cells. This transformation establishes a low-resistance, high-capacity perfusion system from the radial arteries to the intervillous space, in which the villous tree is embedded. The physiology of pregnancy depends upon the orderly progress of structural and functional changes of villous and extravillous trophoblast, whereas a derangement of such processes can lead to different types of complications of varying degrees of gravity, including possible pregnancy loss and maternal life-threatening diseases. In this review we describe the mechanisms which regulate trophoblast differentiation, proliferation, migration and invasiveness, and the alterations in these mechanisms which lead to pathological conditions. Furthermore, based on the growing evidence that proper inflammatory changes and oxidative balance are needed for successful gestation, we explain the mechanisms by which agents able to influence such processes may be useful in the prevention and treatment of pregnancy disorders.

Altered proteome profiles in maternal plasma in pregnancies with fetal growth restriction

Fetal growth restriction (FGR) affects 3–5% of pregnancies and is associated with increased perinatal morbidity and mortality. Currently, there is no reliable biochemical test to differentiate a pathological FGR from a nonpathological one. The objective of this study was to screen whole maternal plasma to identify differentially expressed relatively abundant proteins associated with FGR. We analyzed maternal plasma from FGR (n=28) and healthy (n=22) pregnancies using two-dimensional gel electrophoresis (2D-GE) followed by software image analysis. Three spots with molecular weight (Mr) 18 kDa corresponding to haptoglobin (hp) α2, as identified by LC-MS/MS and immunoblotting, showed differential expression patterns in FGR. The distribution of hp α2 variants in maternal plasma samples showed the hp α2 variant 1 was low in 72% of FGR, medium in 16%, whereas high in 12%. In comparison, hp α2 variant 1 was high in (41%) of controls, medium in 41%, and low in 18% of cases. Based on the software image analysis, the mean spot volume for hp α2 variant 1 was 0.12 (SD=0.18) for FGR compared to 0.26 (SD=0.19) for control (p=0.006). Given that hp turnover is indicative of its maturation process and is traceable in plasma by its dominant/suppressed variants, we propose that hp α2 is an important potential target for evaluation of its clinical and pathophysiological role and as a diagnostic biomarker in FGR.

Genetic relationship between placental and fetal weights and markers of the metabolic syndrome in rat recombinant inbred strains

Epidemiological studies have shown a clear link between fetal growth retardation and an increased propensity for later cardiovascular disease in adults. It has been hypothesized that such early fetal deprivation “programs” individuals toward a life-long metabolical “thrifty phenotype” that predisposes adults to such diseases. Here we test this hypothesis, and its possible genetic basis, in rat recombinant inbred (RI) strains that uniquely allow the longitudinal studies necessary for its testing. Placental and fetal weights were determined on day 20 of pregnancy in (at least) 6 litters from each of 25 available BXH/HXB RI strains and from their SHR and BN-Lx progenitors and were correlated with metabolic traits determined in adult rats from the same inbred lines. Quantitative trait loci (QTLs) associated with placental and fetal weights were identified by total genome scanning of RI strains using the Map Manager QTX program. Heritabilities of placental and fetal weights were 56% and 62%, respectively, and total genome scanning of RI strains revealed QTLs near the D1Rat266 marker on chromosome 1 and near the D15Rat101 marker on chromosome 15 that were significantly associated with fetal and placental weights respectively. Placental weights correlated with fetal weights ( r = 0.60, P = 0.001), while reduced fetal weights correlated with increased insulin concentrations during glucose tolerance test ( r = −0.71, P = 0.0001) and with increased serum triglycerides ( r = −0.54, P = 0.006) in adult rats. Our results suggest that predisposition toward a thrifty phenotype associated with decreased placental weight and restricted fetal growth is in part genetically determined.

Shared and disparate components of the pathophysiologies of fetal growth restriction and preeclampsia

Intrauterine growth restriction (IUGR) and preeclampsia differ in their association with maternal disease but share a similar placental pathology. Moreover, mothers who have had pregnancies complicated by preeclampsia or IUGR are at elevated later-life cardiovascular risk. Why, then, do some women develop IUGR and others develop preeclampsia? In this clinical opinion, based on a review of the literature, we hypothesize that both women experiencing preeclampsia and IUGR enter pregnancy with some degree of endothelial dysfunction, a lesion that predisposes to shallow placentation. In our opinion, preeclampsia develops when abnormal placentation, through the mediator of elevated circulating cytokines, interacts with maternal metabolic syndrome, comprised of adiposity, insulin resistance/hyperglycemia, hyperlipidemia, and coagulopathy. IUGR develops in the absence of antenatal metabolic syndrome. Among these women, the baby is affected by shallow placentation but the mother does not develop clinically apparent disease. This conceptualization provides a testable framework for future etiologic studies of preeclampsia and IUGR.

Expression of Inhibin/activin Subunits alpha (-α), beta A (-β A) and beta B (-β B) in Placental Tissue of Normal and Intrauterine Growth Restricted (IUGR) Pregnancies

During human pregnancy the placenta produces a variety of proteins like steroid hormones and their receptors that are responsible for the establishment and ongoing of the feto-placental unit. Inhibins are dimeric glycoproteins, composed of an alpha-subunit and one of two possible beta-subunits (beta (A) or beta (B)). Aims of the present study were the determination of the frequency and tissue distribution patterns of the inhibin/activin subunits in human placental tissue of normal pregnancies and pregnancies complicated with fetal growth restriction (IUGR). Slides of paraffin embedded placental tissue were obtained after delivery from patients diagnosed with IUGR (n = 6) and normal term placentas (n = 8). Tissue samples were fixed and incubated with monoclonal antibodies inhibin/activin-subunits -alpha, -beta (A), -beta (B). Intensity of immunohistochemical reaction on the slides was analysed using a semi-quantitative score and statistical analysis was performed (P<0.05). A significant lower expression of the inhibin-alpha subunit in IUGR extravillous trophoblast compared to normal pregnancies was observed, while the inhibin-alpha immunostaining was significantly upregulated in syncytiotrophoblast. Additionally, a significant down-regulation of inhibin-beta (B) subunit in extravillous trophoblast cells in IUGR syncytiotrophoblast cells was demonstrated. A co-localisation of inhibin-alpha and the beta-subunits was also observed, suggesting a production and secretion of intact inhibin A and inhibin B. Although the precise role of these inhibin/activin subunits in human placenta and IUGR pregnancies is still unclear, they could be involved in autocrine/paracrine signalling, contributing to several aspects like angiogenesis and tissue remodelling.

Alterations in syncytiotrophoblast cytokine expression following treatment with lipopolysaccharide

PROBLEM

The placental syncytium is a differentiated cell type on the surface of the villus that has the potential to release cytokines directly to maternal blood. Responsiveness of this cell type to inflammatory compounds remains largely unelucidated.

METHOD OF STUDY

Response to a pro-inflammatory (lipopolysaccharide, LPS) and an anti-inflammatory (dexamethasone, DEX) compound was studied in primary cultures of syncytiotrophoblasts (SCTs). Cells were incubated with and without LPS and DEX. Cytokine levels in conditioned media were determined by enzyme-linked immunosorbent assay and proteome arrays.

RESULTS

LPS treatment induced a fourfold increase in interleukin-8 (IL-8) levels in SCTs. LPS enhanced the expression of both pro- and anti-inflammatory cytokines in SCTs. DEX treatment reduced IL-8 levels in control and LPS-treated cultures by 70-90%.

CONCLUSION

Cytokine expression in SCTs was enhanced by LPS treatment and this effect was suppressed by glucocorticoid treatment. This suggests that inflammatory compounds may alter cytokine expression in the syncytium throughout gestation.

Embryotoxicity of the nitric oxide donor sodium nitroprusside in preimplantation bovine embryos in vitro

Many early pregnancy complications are associated with an imbalance in pro- and anti-inflammatory cytokines, resulting in alterations in nitric oxide (NO) profile. Since very little is known about the modus operandi of this free radical in early embryos, this study characterised NO embryotoxicity in terms of bovine embryo development and metabolism. Embryos were generated by in vitro maturation and fertilisation of oocytes aspirated from abattoir-derived ovaries. Zygote to blastocyst rates were measured in SOFaaBSA in the presence and absence of the NO donor sodium nitroprusside (SNP) over the 0-50 microM range (n=10 per group). Since concentrations <10 microM SNP depressed blastocyst rate, blastocyst cell numbers (determined by bisbenzimide staining; n=22 and 20), glucose, pyruvate, lactate (measured ultramicrofluorometrically) and amino acid profiles (quantified by HPLC; n=28 and 23) were assessed at 0 and 10 microM SNP. SNP depressed cell numbers, reduced pyruvate and glucose uptake, perturbed quantitative tyrosine, threonine, phenylalanine, lysine, glycine, tryptophan, methionine and valine profiles, and decreased retention into the negative range (P<0.05). Qualitative asparagine and lysine profiles were affected by SNP, while proportional amino acid production and consumption were increased and decreased, respectively (P<0.05). These findings indicate that SNP (presumably through increases in NO profile): (i) fails to improve bovine embryo development in vitro, (ii) exerts toxic effects, likely through ATP starvation induced by cytochrome c oxidase (oxidative phosphorylation) and glyceraldehyde-3-phosphate dehydrogenase (glycolysis) inhibition, and (iii) may affect albumin endocytosis/hydrolysis or protein biosynthesis, rather than causing a loss of intracellular amino acids or simply depressing their metabolism.

Hypoxia-induced leptin production in human trophoblasts does not protect from apoptosis

OBJECTIVE

The ob-gene product, leptin, is an important regulator of placental and fetal development during pregnancy. Leptin, being induced by hypoxia in the placenta, is a known pro-apoptotic molecule in adipose tissue but is also known to inhibit apoptosis in other tissues like neuroblastoma cells. Based on these findings, we investigated if leptin has a pro- or anti-apoptotic effect on a trophoblastic cell line (JAr cells) in the presence or absence of oxygen.

METHODS AND RESULTS

Measurement of leptin in the supernatant by using ELISA showed hypoxia-induced leptin production in JAr cells in vitro. This could be confirmed by a leptin-specific RT-PCR. By analyzing leptin and/or hypoxia exposed cells with FACS cytometry we found that JAr cells can cope with hypoxia down to oxygen tensions of 1%. At this level, only a small number of cells underwent apoptosis. Interestingly, leptin added to the culture medium in high concentrations was not able to interfere with the rate of proliferation or apoptosis in these cells independent of the oxygen tension. Finally, an anti-caspase-3 and anti-caspase-9 Western blot was performed. Again, no difference in the expression of caspase-3 and -9 under the conditions tested was seen.

CONCLUSIONS

These results show that leptin, produced by placental cells after hypoxia in vitro, has no influence on the rate of proliferation of these cells. Furthermore, it does not influence apoptotic pathways in the trophoblastic cell line tested under hypoxic and non-hypoxic conditions.

Genetic and environmental influences on birthweight in a sample of Korean twins

This study is the first report of genetic and environmental influences on birthweight using Korean twins. The sample consisted of 255 monozygotic (MZ) and 178 dizygotic (DZ) twin pairs drawn from the Seoul Twin Family Study. Intraclass twin correlations were computed for the twins' birthweights obtained from parents (typically mothers) of the twins. To estimate genetic and shared and nonshared environmental influences on birthweight, standard univariate model-fitting analyses were performed using a software, Mx. For each gender, MZ twin correlations were higher than DZ twin correlations, suggesting existence of genetic influences on birthweight; however, DZ twin correlations were higher than half the MZ twin correlations, indicating that shared environmental factors are also important. For each zygosity, twin correlations were not significantly different between males and females, implicating that genes and environments that cause individual differences in birthweight may not vary between males and females. Model-fitting analyses based on the data pooled across gender yielded estimates of 17% for genetic, 60% for shared environmental, and 23% for nonshared environmental influences on birthweight.

Pre-eclampsia

Pre-eclampsia is a major cause of maternal mortality (15-20% in developed countries) and morbidities (acute and long-term), perinatal deaths, preterm birth, and intrauterine growth restriction. Key findings support a causal or pathogenetic model of superficial placentation driven by immune maladaptation, with subsequently reduced concentrations of angiogenic growth factors and increased placental debris in the maternal circulation resulting in a (mainly hypertensive) maternal inflammatory response. The final phenotype, maternal pre-eclamptic syndrome, is further modulated by pre-existing maternal cardiovascular or metabolic fitness. Currently, women at risk are identified on the basis of epidemiological and clinical risk factors, but the diagnostic criteria of pre-eclampsia remain unclear, with no known biomarkers. Treatment is still prenatal care, timely diagnosis, proper management, and timely delivery. Many interventions to lengthen pregnancy (eg, treatment for mild hypertension, plasma-volume expansion, and corticosteroid use) have a poor evidence base. We review findings on the diagnosis, risk factors, and pathogenesis of pre-eclampsia and the present status of its prediction, prevention, and management.