Correlation between essential and toxic elements in maternal blood during early pregnancy and atrial septal defects/ventricular septal defects/patent ductus arteriosus in offspring

BACKGROUND

Congenital heart defects (CHDs) are the most common congenital malformation in the world. Recent studies have found that essential and toxic trace element levels may play a crucial role in the risk of neonatal malformation. However, the relationships between element levels in early pregnancy and CHD risk among humans remain unclear. This study investigates the association between maternal essential element (copper [Cu], zinc [Zn], calcium [Ca], manganese [Mg] and iron [Fe]) and toxic element (lead [Pb] and cadmium [Cd]) levels during early pregnancy and CHDs.

METHODS

A hospital-based case-control study was conducted, including 181 cases and 218 controls. Eligible participants underwent antenatal examination during gestational weeks 11-14 and trace element levels were detected by the atomic absorption method. Multi-variable logistic regression was used to examine the associations between the level of maternal trace elements and CHD risks.

RESULTS

Higher levels of Ca in early pregnancy were associated with lower risk of ASD/VSD risks. Moreover, higher Fe, Pb, and Cd levels in the first trimester were associated with higher risks of all CHD and the subtypes risks, and the tests for trend were significant (all p < .05). The restricted cubic spline analysis showed that there was a nonlinear inverted u-shaped dose-response relationship between levels of Zn, Pb, and Cd in the first trimester and risk of CHDs (non-linearity test p < .05).

CONCLUSIONS

A moderate increase in Zn and Ca levels and a decrease in Pb and Cd levels during early pregnancy are needed to reduce the incidence of CHDs in the Chinese population.

The role of pregnancy associated plasma protein-A in triple negative breast cancer: a promising target for achieving clinical benefits

Pregnancy associated plasma protein-A (PAPP-A) plays an integral role in breast cancer (BC), especially triple negative breast cancer (TNBC). This subtype accounts for the most aggressive BC, possesses high tumor heterogeneity, is least responsive to standard treatments and has the poorest clinical outcomes. There is a critical need to address the lack of effective targeted therapeutic options available. PAPP-A is a protein that is highly elevated during pregnancy. Frequently, higher PAPP-A expression is detected in tumors than in healthy tissues. The increase in expression coincides with increased rates of aggressive cancers. In BC, PAPP-A has been demonstrated to play a role in tumor initiation, progression, metastasis including epithelial-mesenchymal transition (EMT), as well as acting as a biomarker for predicting patient outcomes. In this review, we present the role of PAPP-A, with specific focus on TNBC. The structure and function of PAPP-A, belonging to the pappalysin subfamily, and its proteolytic activity are assessed. We highlight the link of BC and PAPP-A with respect to the IGFBP/IGF axis, EMT, the window of susceptibility and the impact of pregnancy. Importantly, the relevance of PAPP-A as a TNBC clinical marker is reviewed and its influence on immune-related pathways are explored. The relationship and mechanisms involving PAPP-A reveal the potential for more treatment options that can lead to successful immunotherapeutic targets and the ability to assist with better predicting clinical outcomes in TNBC.

Two distinct molecular faces of preeclampsia revealed by single-cell transcriptomics

INTRODUCTION

Preeclampsia is a multisystemic, pregnancy-specific disorder united by new-onset hypertension but with considerable variation in clinical manifestation, onset, and severity. For symptoms to regress, delivery of the placenta is required. For symptoms to regress, delivery of the placenta is required, making the placenta central to preeclampsia pathophysiology. To dissect which placental functions were impacted in two forms of preeclampsia, we studied molecular changes across the cell types of the placenta.

METHODS

We performed a transcriptomic survey of single-cells and single-nuclei on cases of early- and late-onset preeclampsia with gestation-matched controls.

FINDINGS

Our data revealed massive dysregulation of gene expression in all cell classes that was almost exclusive to early preeclampsia. For example, an important known receptor/ligand imbalance hallmarking angiogenic disfunction, sFLT1/placental growth factor (PGF), was reflected in striking, cell-autonomous dysregulation of FLT1 and PGF transcription in the syncytium in early preeclampsia only. Stromal cells and vasculature echoed an inflamed, stressed, anti-angiogenic environment. Finally, the placental immune niche set the tone for inflammation in early but not late preeclampsia. Here, fetal-origin Hofbauer and maternal-origin TREM2 macrophages were revealed as surprising main actors, while local cells of the adaptive immune system were largely unaffected. Late preeclampsia showed minimal cellular impact on the placenta.

CONCLUSIONS

Our survey provides systematic molecular evidence for two distinct diseases. We resolved systematic molecular dysregulation to individual cell types with strong implications for definition, early detection, diagnosis, and treatment.

FUNDING

Funded by the Preeclampsia Foundation through the Peter Joseph Pappas Research Grant.

Biochemical Screening for Fetal Trisomy 21: Pathophysiology of Maternal Serum Markers and Involvement of the Placenta

It is now well established that maternal serum markers are often abnormal in fetal trisomy 21. Their determination is recommended for prenatal screening and pregnancy follow-up. However, mechanisms leading to abnormal maternal serum levels of such markers are still debated. Our objective was to help clinicians and scientists unravel the pathophysiology of these markers via a review of the main studies published in this field, both in vivo and in vitro, focusing on the six most widely used markers (hCG, its free subunit hCGβ, PAPP-A, AFP, uE3, and inhibin A) as well as cell-free feto-placental DNA. Analysis of the literature shows that mechanisms underlying each marker's regulation are multiple and not necessarily directly linked with the supernumerary chromosome 21. The crucial involvement of the placenta is also highlighted, which could be defective in one or several of its functions (turnover and apoptosis, endocrine production, and feto-maternal exchanges and transfer). These defects were neither constant nor specific for trisomy 21, and might be more or less pronounced, reflecting a high variability in placental immaturity and alteration. This explains why maternal serum markers can lack both specificity and sensitivity, and are thus restricted to screening.

Identification and validation of an angiogenesis-related signature associated with preeclampsia by bioinformatic analysis

Preeclampsia (PE) is a pregnancy disorder with high morbidity and mortality rates for both mothers and newborns. This study explores potential diagnostic indicators of PE. We downloaded the messenger ribonucleic acid profiles of the GSE75010 dataset from the Gene Expression Omnibus database, and used placenta samples to carry out different analyses including differential expression, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes analyses. Least absolute shrinkage and selection operator regression was constructed and the receiver operating characteristic curve was drawn to evaluate the accuracy of the model. An external validation was conducted to prove the stability of the risk model. We found 140 angiogenesis-related genes and identified 29 angiogenesis-related genes between the 2 groups, including 12 upregulated genes and 17 downregulated genes. In addition, we established a 12-gene risk signature, which has a high accuracy in predicting PE during pregnancy (area under curve = 0.90). The immune infiltration characteristics are differentially distributed in the 2 groups, which may be the cause of hypertension during pregnancy. The external validation with the GSE25906 dataset confirmed the high accuracy of our model (area under curve = 0.87). Our results outline the characteristics of a set of genes potentially involved in PE and its subgroups, contributing to a better understanding of the molecular mechanisms of PE.

Structural insights into the covalent regulation of PAPP-A activity by proMBP and STC2

Originally discovered in the circulation of pregnant women as a protein secreted by placental trophoblasts, the metalloprotease pregnancy-associated plasma protein A (PAPP-A) is also widely expressed by many other tissues. It cleaves insulin-like growth factor-binding proteins (IGFBPs) to increase the bioavailability of IGFs and plays essential roles in multiple growth-promoting processes. While the vast majority of the circulatory PAPP-A in pregnancy is proteolytically inactive due to covalent inhibition by proform of eosinophil major basic protein (proMBP), the activity of PAPP-A can also be covalently inhibited by another less characterized modulator, stanniocalcin-2 (STC2). However, the structural basis of PAPP-A proteolysis and the mechanistic differences between these two modulators are poorly understood. Here we present two cryo-EM structures of endogenous purified PAPP-A in complex with either proMBP or STC2. Both modulators form 2:2 heterotetramer with PAPP-A and establish extensive interactions with multiple domains of PAPP-A that are distal to the catalytic cleft. This exosite-binding property results in a steric hindrance to prevent the binding and cleavage of IGFBPs, while the IGFBP linker region-derived peptides harboring the cleavage sites are no longer sensitive to the modulator treatment. Functional investigation into proMBP-mediated PAPP-A regulation in selective intrauterine growth restriction (sIUGR) pregnancy elucidates that PAPP-A and proMBP collaboratively regulate extravillous trophoblast invasion and the consequent fetal growth. Collectively, our work reveals a novel covalent exosite-competitive inhibition mechanism of PAPP-A and its regulatory effect on placental function.

Human Plasma Proteome During Normal Pregnancy

The human plasma proteome is underexplored despite its potential value for monitoring health and disease. Herein, using a recently developed aptamer-based platform, we profiled 7288 proteins in 528 plasma samples from 91 normal pregnancies (Gene Expression Omnibus identifier GSE206454). The coefficient of variation was <20% for 93% of analytes (median 7%), and a cross-platform correlation for selected key angiogenic and anti-angiogenic proteins was significant. Gestational age was associated with changes in 953 proteins, including highly modulated placenta- and decidua-specific proteins, and they were enriched in biological processes including regulation of growth, angiogenesis, immunity, and inflammation. The abundance of proteins corresponding to RNAs specific to populations of cells previously described by single-cell RNA-Seq analysis of the placenta was highly modulated throughout gestation. Furthermore, machine learning-based prediction of gestational age and of time from sampling to term delivery compared favorably with transcriptomic models (mean absolute error of 2 weeks). These results suggested that the plasma proteome may provide a non-invasive readout of placental cellular dynamics and serve as a blueprint for investigating obstetrical disease.

Vitamin D3 reverses the transcriptional profile of offspring CD4+ T lymphocytes exposed to intrauterine inflammation

Chorioamnionitis profoundly influences multiple fetal organs as well as the immune system. Maternal vitamin D (VitD) supplementation may modulate the immune function of offspring. Here, we sought to uncover the immunomodulatory potential of intrauterine inflammation and VitD in offspring CD4⁺ T cells. Pregnant C57BL/6 mice were treated with intrauterine lipopolysaccharide (LPS) injections, with or without VitD. Splenic CD4⁺ T cells were negatively selected using anti-biotin microbeads at 28 days after birth. Differentially expressed genes (DEGs) in the offspring CD4⁺ T cells were identified via RNA sequencing. In total, 181 DEGs induced by LPS exposure were identified in offspring CD4⁺ T cells. Furthermore, 2461 DEGs were detected after VitD supplementation in addition to LPS exposure. VitD supplementation showed an unexpected ability to counteract the LPS-induced transcriptional responses. VitD supplementation downregulated lymphocyte differentiation (GO: 0030098) and lymphocyte activation (GO: 0046649), and upregulated the responses to viruses (GO: 0009615) and bacteria (GO:0009617) in offspring CD4⁺ T cells with intrauterine LPS exposure. In addition, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that several pathways, including the T cell receptor signaling pathway, the mitogen-activated protein kinase (MAPK) signaling pathway, Th17 cell differentiation, and autophagy, were downregulated by intrauterine VitD intervention following LPS exposure. Subsequently, we confirmed the counteracting effect of VitD against LPS on the expression of several genes (Insr, Foxo1, and Peli1) using qRT-PCR and western blot analyses. We also demonstrated that intrauterine VitD supplementation interferes with offspring Th17 cell differentiation induced by intrauterine LPS exposure. Our study revealed that VitD reverses the transcriptional and Th17 differential profiles of offspring CD4⁺ T lymphocytes induced by intrauterine LPS, and indicated the contribution of maternal VitD supplementation to immune protection in offspring affected by intrauterine inflammation.

The correlation between proteoglycan 2 and neuropsychiatric systemic lupus erythematosus

The proposed pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) mainly includes ischemia and neuroinflammation mechanisms. Protein encoded by Proteoglycan 2 (PRG2) mRNA is involved in the immune process related to eosinophils, also being found in the placenta and peripheral blood of pregnant women. We evaluated the correlation between PRG2 and NPSLE for the first time and found that PRG2 protein is overexpressed in the serum of patients with NPSLE and correlated with the SLE disease activity index (SLEDAI) subset scores of psychosis. Moreover, we investigated the correlation between hippocampal PRG2 level and hippocampally dependent learning and memory ability in MRL/lpr mice, and discovered that the number of PRG2⁺GFAP⁺ astrocytes in the cortex and hypothalamus and the number of PRG2⁺IBA-1⁺ microglia in the hippocampus and cortex significantly increased in the MRL/lpr mice. These data provided a reference for the follow-up exploration of the role of PRG2 in SLE or other diseases.

Circulating transcripts in maternal blood reflect a molecular signature of early-onset preeclampsia

Circulating RNA (C-RNA) is continually released into the bloodstream from tissues throughout the body, offering an opportunity to noninvasively monitor all aspects of pregnancy health from conception to birth. We asked whether C-RNA analysis could robustly detect aberrations in patients diagnosed with preeclampsia (PE), a prevalent and potentially fatal pregnancy complication. As an initial examination, we sequenced the circulating transcriptome from 40 pregnancies at the time of severe, early-onset PE diagnosis and 73 gestational age-matched controls. Differential expression analysis identified 30 transcripts with gene ontology annotations and tissue expression patterns consistent with the placental dysfunction, impaired fetal development, and maternal immune and cardiovascular system dysregulation characteristic of PE. Furthermore, machine learning identified combinations of 49 C-RNA transcripts that classified an independent cohort of patients (early-onset PE, n = 12; control, n = 12) with 85 to 89% accuracy. C-RNA may thus hold promise for improving the diagnosis and identification of at-risk pregnancies.

PRG2 and AQPEP are misexpressed in fetal membranes in placenta previa and percreta†

The obstetrical conditions placenta accreta spectrum (PAS) and placenta previa are a significant source of pregnancy-associated morbidity and mortality, yet the specific molecular and cellular underpinnings of these conditions are not known. In this study, we identified misregulated gene expression patterns in tissues from placenta previa and percreta (the most extreme form of PAS) compared with control cases. By comparing this gene set with existing placental single-cell and bulk RNA-Seq datasets, we show that the upregulated genes predominantly mark extravillous trophoblasts. We performed immunofluorescence on several candidate molecules and found that PRG2 and AQPEP protein levels are upregulated in both the fetal membranes and the placental disk in both conditions. While this increased AQPEP expression remains restricted to trophoblasts, PRG2 is mislocalized and is found throughout the fetal membranes. Using a larger patient cohort with a diverse set of gestationally aged-matched controls, we validated PRG2 as a marker for both previa and PAS and AQPEP as a marker for only previa in the fetal membranes. Our findings suggest that the extraembryonic tissues surrounding the conceptus, including both the fetal membranes and the placental disk, harbor a signature of previa and PAS that is characteristic of EVTs and that may reflect increased trophoblast invasiveness.

Optic nerve regeneration screen identifies multiple genes restricting adult neural repair

Adult mammalian central nervous system (CNS) trauma interrupts neural networks and, because axonal regeneration is minimal, neurological deficits persist. Repair via axonal growth is limited by extracellular inhibitors and cell-autonomous factors. Based on results from a screen in vitro, we evaluate nearly 400 genes through a large-scale in vivo regeneration screen. Suppression of 40 genes using viral-driven short hairpin RNAs (shRNAs) promotes retinal ganglion cell (RGC) axon regeneration after optic nerve crush (ONC), and most are validated by separate CRISPR-Cas9 editing experiments. Expression of these axon-regeneration-suppressing genes is not significantly altered by axotomy. Among regeneration-limiting genes, loss of the interleukin 22 (IL-22) cytokine allows an early, yet transient, inflammatory response in the retina after injury. Reduced IL-22 drives concurrent activation of signal transducer and activator of transcription 3 (Stat3) and dual leucine zipper kinase (DLK) pathways and upregulation of multiple neuron-intrinsic regeneration-associated genes (RAGs). Including IL-22, our screen identifies dozens of genes that limit CNS regeneration. Suppression of these genes in the context of axonal damage could support improved neural repair.

Placental proteome abnormalities in women with gestational diabetes and large-for-gestational-age newborns

INTRODUCTION

Gestational diabetes mellitus (GDM) is the most frequent metabolic complication during pregnancy and is associated with development of short-term and long-term complications for newborns, with large-for-gestational-age (LGA) being particularly common. Interestingly, the mechanism behind altered fetal growth in GDM is only partially understood.

RESEARCH DESIGN AND METHODS

A proteomic approach was used to analyze placental samples obtained from healthy pregnant women (n=5), patients with GDM (n=12) and with GDM and LGA (n=5). Effects of altered proteins on fetal development were tested in vitro in human embryonic stem cells (hESCs).

RESULTS

Here, we demonstrate that the placental proteome is altered in pregnant women affected by GDM with LGA, with at least 37 proteins differentially expressed to a higher degree (p<0.05) as compared with those with GDM but without LGA. Among these proteins, 10 are involved in regulating tissue differentiation and/or fetal growth and development, with bone marrow proteoglycan (PRG2) and dipeptidyl peptidase-4 (DPP-4) being highly expressed. Both PRG2 and DPP-4 altered the transcriptome profile of stem cells differentiation markers when tested in vitro in hESCs, suggesting a potential role in the onset of fetal abnormalities.

CONCLUSIONS

Our findings suggest that placental dysfunction may be directly responsible for abnormal fetal growth/development during GDM. Once established on a larger population, inhibitors of the pathways involving those altered factors may be tested in conditions such as GDM and LGA, in which therapeutic approaches are still lacking.

Congenital Transmission of Trypanosoma cruzi: A Review About the Interactions Between the Parasite, the Placenta, the Maternal and the Fetal/Neonatal Immune Responses

Chagas disease (CD), caused by the protozoan parasite Trypanosoma cruzi, is considered a neglected tropical disease by the World Health Organization. Congenital transmission of CD is an increasingly relevant public health problem. It progressively becomes the main transmission route over others and can occur in both endemic and non-endemic countries. Though most congenitally infected newborns are asymptomatic at birth, they display higher frequencies of prematurity, low birth weight, and lower Apgar scores compared to uninfected ones, and some suffer from severe symptoms. If not diagnosed and treated, infected newborns are at risk of developing disabling and life-threatening chronic pathologies later in life. The success or failure of congenital transmission depends on interactions between the parasite, the placenta, the mother, and the fetus. We review and discuss here the current knowledge about these parameters, including parasite virulence factors such as exovesicles, placental tropism, potential placental defense mechanisms, the placental transcriptome of infected women, gene polymorphism, and the maternal and fetal/neonatal immune responses, that might modulate the risk of T. cruzi congenital transmission.

Re-Expression of Bone Marrow Proteoglycan-2 by 5-Azacytidine is associated with STAT3 Inactivation and Sensitivity Response to Imatinib in Resistant CML Cells

Background:

Epigenetic silencing of tumor suppressor genes (TSG) is involved in development and progression of cancers. Re-expression of TSG is inversely proportionate with STAT3 signaling pathways. Demethylation of DNA by 5-Azacytidine (5-Aza) results in re-expression of silenced TSG. Forced expression of PRG2 by 5-Aza induced apoptosis in cancer cells. Imatinib is a tyrosine kinase inhibitor that potently inhibits BCR/ABL tyrosine kinase resulting in hematological remission in CML patients. However, majority of CML patients treated with imatinib would develop resistance under prolonged therapy.

Methods:

CML cells resistant to imatinib were treated with 5-Aza and cytotoxicity of imatinib and apoptosis were determined by MTS and annexin-V, respectively. Gene expression analysis was detected by real time-PCR, STATs activity examined using Western blot and methylation status of PRG2 was determined by pyrosequencing analysis.

Result:

Expression of PRG2 was significantly higher in K562-R+5-Aza cells compared to K562 and K562-R (p=0.001). Methylation of PRG2 gene was significantly decreased in K562-R+5-Aza cells compared to other cells (p=0.021). STAT3 was inactivated in K562-R+5-Aza cells which showed higher sensitivity to imatinib.

Conclusion:

PRG2 gene is a TSG and its overexpression might induce sensitivity to imatinib. However, further studies are required to evaluate the negative regulations of PRG2 on STAT3 signaling.

Alterations in Placental Gene Expression of Pregnant Women with Chronic Chagas Disease

Trypanosoma cruzi infection in women of reproductive age is associated with congenital transmission and adverse pregnancy outcomes. The placenta is a key barrier to infection. Gene expression profiles of term placental environment from T. cruzi-seropositive (SP) and -seronegative (SN) mothers were characterized by RNA-Seq. Nine pools of placental RNA paired samples were used: three from SN and six from SP tissues. Each pool consisted of female/male newborns and vaginal/cesarean delivery binomials. No newborn was congenitally infected. T. cruzi satellite DNA quantitative PCR in placental tissues and maternal and neonatal blood, and parasite 18S quantitative RT-PCR from placental RNA were negative, except in three SP women's bloodstream. To identify pathways associated with maternal T. cruzi infection, a gene-set association analysis was implemented: SP placental samples showed overexpression of inflammatory response and lymphocytic activation, whereas numerous biosynthetic processes were down-regulated. About 42 genes showed a significant fold-change between SP and SN groups. KISS1 and CGB5 were down-regulated, whereas KIF12, HLA-G, PRG2, TAC3, FN1, and ATXN3L were up-regulated. Several expressed genes in SP placentas encode proteins associated with preeclampsia and miscarriage. This first transcriptomics study in human term placental environment shows a placental response that may affect the fetus while protecting it from parasite infection; this host response could be responsible for the low rate of congenital transmission in chronic Chagas disease.

Preeclampsia: novel insights from global RNA profiling of trophoblast subpopulations

BACKGROUND

The maternal signs of preeclampsia, which include the new onset of high blood pressure, can occur because of faulty placentation. We theorized that transcriptomic analyses of trophoblast subpopulations in situ would lend new insights into the role of these cells in preeclampsia pathogenesis.

OBJECTIVE

Our goal was to enrich syncytiotrophoblasts, invasive cytotrophoblasts, or endovascular cytotrophoblasts from the placentas of severe preeclampsia cases. Total RNA was subjected to global transcriptional profiling to identify RNAs that were misexpressed compared with controls.

STUDY DESIGN

This was a cross-sectional analysis of placentas from women who had been diagnosed with severe preeclampsia. Gestational age-matched controls were placentas from women who had a preterm birth with no signs of infection. Laser microdissection enabled enrichment of syncytiotrophoblasts, invasive cytotrophoblasts, or endovascular cytotrophoblasts. After RNA isolation, a microarray approach was used for global transcriptional profiling. Immunolocalization identified changes in messenger RNA expression that carried over to the protein level. Differential expression of non-protein-coding RNAs was confirmed by in situ hybridization. A 2-way analysis of variance of non-coding RNA expression identified particular classes that distinguished trophoblasts in cases vs controls. Cajal body foci were visualized by coilin immunolocalization.

RESULTS

Comparison of the trophoblast subtype data within each group (severe preeclampsia or noninfected preterm birth) identified many highly differentially expressed genes. They included molecules that are known to be expressed by each subpopulation, which is evidence that the method worked. Genes that were expressed differentially between the 2 groups, in a cell-type-specific manner, encoded a combination of molecules that previous studies associated with severe preeclampsia and those that were not known to be dysregulated in this pregnancy complication. Gene ontology analysis of the syncytiotrophoblast data highlighted the dysregulation of immune functions, morphogenesis, transport, and responses to vascular endothelial growth factor and progesterone. The invasive cytotrophoblast data provided evidence of alterations in cellular movement, which is consistent with the shallow invasion often associated with severe preeclampsia. Other dysregulated pathways included immune, lipid, oxygen, and transforming growth factor-beta responses. The data for endovascular cytotrophoblasts showed disordered metabolism, signaling, and vascular development. Additionally, the transcriptional data revealed the differential expression in severe preeclampsia of 2 classes of non-coding RNAs: long non-coding RNAs and small nucleolar RNAs. The long non-coding RNA, urothelial cancer associated 1, was the most highly up-regulated in this class. In situ hybridization confirmed severe preeclampsia-associated expression in syncytiotrophoblasts. The small nucleolar RNAs, which chemically modify RNA structure, also correlated with severe preeclampsia. Thus, we enumerated Cajal body foci, sites of small nucleolar RNA activity, in primary cytotrophoblasts that were isolated from control and severe preeclampsia placentas. In severe preeclampsia, cytotrophoblasts had approximately double the number of these foci as the control samples.

CONCLUSION

A laser microdissection approach enabled the identification of novel messenger RNAs and non-coding RNAs that were misexpressed by various trophoblast subpopulations in severe preeclampsia. The results suggested new avenues of investigation, in particular, the roles of PRG2, Kell blood group determinants, and urothelial cancer associated 1 in syncytiotrophoblast diseases. Additionally, many of the newly identified dysregulated molecules might have clinical utility as biomarkers of severe preeclampsia.

Expression of the placental transcriptome in maternal nutrient reduction in baboons is dependent on fetal sex

Maternal undernutrition increases the risk of perinatal complications and predisposes offspring to obesity, diabetes, and cardiovascular disease later in life. Emerging evidence suggests that changes in placental function play a role in linking altered maternal nutrition in pregnancy to the subsequent development of adult disease. The susceptibility for disease in response to an adverse intrauterine environment differs distinctly between boys and girls, with girls typically having better outcomes. Here, we tested the hypothesis that regulation of the placental transcriptome by maternal nutrient reduction (NR) is dependent on fetal sex. We used a nonhuman primate model of NR in which maternal global food intake was reduced by 30% in baboons starting at gestational day (GD) 30. At GD 165 (term = GD 183), placental genome expression profiling of 6 control (n = 3 females, 3 males) and 6 nutrient restricted (n = 3 females, 3 males) fetuses was carried out followed by bioinformatic analysis. Surprisingly, there was no coordinated placental molecular response to decreased nutrient availability when analyzing the data without accounting for fetal sex. In contrast, female placentas exhibited a highly coordinated response that included upregulation of genes in networks, pathways, and functional groups related to programmed cell death and downregulation of genes in networks, pathways, and functional groups associated with cell proliferation. These changes were not apparent in the male placentas. Our data support the concept that female placentas initiate complex adaptive responses to an adverse intrauterine environment, which may contribute to increased survival and better pregnancy outcomes in girls.

Roles of the circulating renin-angiotensin-aldosterone system in human pregnancy

This review describes the changes that occur in circulating renin-angiotensin-aldosterone system (RAAS) components in human pregnancy. These changes depend on endocrine secretions from the ovary and possibly the placenta and decidua. Not only do these hormonal secretions directly contribute to the increase in RAAS levels, they also cause physiological changes within the cardiovascular system and the kidney, which, in turn, induce reflex release of renal renin. High levels of ANG II play a critical role in maintaining circulating blood volume, blood pressure, and uteroplacental blood flow through interactions with the ANG II type I receptor and through increased production of downstream peptides acting on a changing ANG receptor phenotype. The increase in ANG II early in gestation is driven by estrogen-induced increments in angiotensinogen (AGT) levels, so there cannot be negative feedback leading to reduced ANG II production. AGT can exist in various forms in terms of redox state or complexed with other proteins as polymers; these affect the ability of renin to cleave ANG I from AGT. Thus, during pregnancy the rate of ANG I production varies not only because levels of renin change in response to homeostatic demand but also because AGT changes not only in concentration but in form. Activation of the circulating and intrarenal RAASs is essential for normal pregnancy outcome subserving the increased demand for salt and, hence, water during pregnancy. Thus, the complex integration of the secretions and actions of the circulating maternal renin-angiotensin system in pregnancy plays a key role in pregnancy outcome.

Gfi-1 inhibits the expression of eosinophil major basic protein (MBP) during G-CSF-induced neutrophilic differentiation

The zinc finger transcriptional repressor Gfi-1 has been shown to play a critical role in early granulopoiesis; however, its role in late neutrophilic development is poorly understood. We report here that forced expression of a dominant negative Gfi-1 mutant, N382S, resulted in augmented mRNA levels of eosinophil major basic protein (MBP) in myeloid cells induced with G-CSF to undergo terminal neutrophilic differentiation. MBP is a cytotoxic protein that is abundantly expressed in eosinophils, but not in neutrophils. Ectopic expression of MBP inhibited the proliferation and survival of differentiating myeloid cells in response to G-CSF. Significantly, while GFI-1 is upregulated during neutrophilic differentiation, it is rapidly downregulated upon induction of eosinophilic differentiation, which was associated with increased MBP expression. Knockdown of GFI-1 in eosinophilic cells also led to increased level of MBP mRNA. These results indicate that Gfi-1 functions to inhibit the expression of MBP and aberrant expression of MBP as a result of loss of Gfi-1 function may cause premature apoptosis of differentiating neutrophils. In contrast, the rapid downregulation of Gfi-1 during eosinophilic development may allow for abundant expression of MBP, a hallmark of eosinophilic differentiation.