Maternal uterine artery VEGF gene therapy for treatment of intrauterine growth restriction

Placental Drug Delivery to Treat Pre-Eclampsia and Fetal Growth Restriction

Pre-eclampsia and fetal growth restriction (FGR) continue to cause unacceptably high levels of morbidity and mortality, despite significant pharmaceutical and technological advances in other disease areas. The recent pandemic has also impacted obstetric care, as COVID-19 infection increases the risk of poor pregnancy outcomes. This review explores the reasons why it lacks effective drug treatments for the placental dysfunction that underlies many common obstetric conditions and describes how nanomedicines and targeted drug delivery approaches may provide the solution to the current drug drought. The ever-increasing range of biocompatible nanoparticle formulations available is now making it possible to selectively deliver drugs to uterine and placental tissues and dramatically limit fetal drug transfer. Formulations that are refractory to placental uptake offer the possibility of retaining drugs within the maternal circulation, allowing pregnant individuals to take medicines previously considered too harmful to the developing baby. Liposomes, ionizable lipid nanoparticles, polymeric nanoparticles, and adenoviral vectors have all been used to create efficacious drug delivery systems for use in pregnancy, although each approach offers distinct advantages and limitations. It is imperative that recent advances continue to be built upon and that there is an overdue investment of intellectual and financial capital in this field.

Mortality and severe neurological morbidity in extremely preterm growth-restricted fetuses

OBJECTIVE

To develop a model for the prediction of adverse perinatal outcome in growth-restricted fetuses requiring delivery before 28 weeks in order to provide individualized patient counseling.

METHODS

This was a retrospective multicenter cohort study of singleton pregnancies with antenatal suspicion of fetal growth restriction requiring delivery before 28 weeks' gestation between January 2010 and January 2020 in six tertiary public hospitals in the Barcelona area, Spain. Separate predictive models for mortality only and mortality or severe neurological morbidity were created using logistic regression from variables available antenatally. For each model, predictive performance was evaluated using receiver-operating-characteristics (ROC)-curve analysis. Predictive models were validated externally in an additional cohort of growth-restricted fetuses from another public tertiary hospital with the same inclusion and exclusion criteria.

RESULTS

A total of 110 cases were included. The neonatal mortality rate was 37.3% and, among the survivors, the rate of severe neurological morbidity was 21.7%. The following factors were retained in the multivariate analysis as significant predictors of mortality: magnesium sulfate neuroprotection, gestational age at birth, estimated fetal weight, male sex and Doppler stage. This model had a significantly higher area under the ROC curve (AUC) compared with a model including only gestational age at birth (0.810 (95% CI, 0.730-0.889) vs 0.695 (95% CI, 0.594-0.795); P = 0.016). At a 20% false-positive rate, the model showed a sensitivity, negative predictive value and positive predictive value of 66%, 80% and 66%, respectively. For the prediction of the composite adverse outcome (mortality or severe neurological morbidity), the model included: gestational age at birth, male sex and Doppler stage. This model had a significantly higher AUC compared with a model including only gestational age at birth (0.810 (95% CI, 0.731-0.892) vs 0.689 (95% CI, 0.588-0.799); P = 0.017). At a 20% false-positive rate, the model showed a sensitivity, negative predictive value and positive predictive value of 55%, 63% and 74%, respectively. External validation of both models yielded similar AUCs that did not differ significantly from those obtained in the original sample.

CONCLUSIONS

Estimated fetal weight, fetal sex and Doppler stage can be combined with gestational age to improve the prediction of death or severe neurological sequelae in growth-restricted fetuses requiring delivery before 28 weeks. This approach may be useful for parental counseling and decision-making. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Comparison of VEGF-A levels in women with threatened abortion, early pregnancy loss and uncomplicated healthy pregnancies

INTRODUCTION

To estimate the possible role of VEGF-A in predicting poor early pregnancy outcomes including threatened abortion and early pregnancy loss.

METHODS

We conducted a prospective case-control study with three groups of pregnant women diagnosed with threatened abortion, early pregnancy loss, and uncomplicated healthy pregnancies between 01 March 2023 and 15 March 2023. Maternal serum VEGF-A concentration was measured using the Sandwich-ELISA method in accordance to the commercial kit's instructions. There were 30 patients in each 3 group and the gestational age of the patients was between 6 and 14 weeks. The Kruskal-Wallis test was performed for comparing the median values between the groups. Mann-Whitney U test was conducted for pairwise comparisons.

RESULTS

VEGF-A levels were compared between 3 groups and a statistically significant difference was found (p = 0.007). There was a moderately significant correlation between VEGF-A levels and poor early pregnancy outcomes. For poor early pregnancy outcomes, the area under the curve (AUC) was 0.75 (95% CI: 0.64-0.85). The best balance of sensitivity/specificity in ROC curves was 0.60 (63.3% sensitivity, 74.3% specificity).

DISCUSSION

In conclusion, this study pointed out the increased VEGF concentrations in pregnant women with threatened miscarriage and early pregnancy loss. VEGF-A may be a potential biomarker for the indication of poor early pregnancy outcomes.

Scaling the EVERREST of severe, early-onset fetal growth restriction

Severe, early-onset fetal growth restriction is a leading cause of medically indicated preterm birth and substantially increases the risk for perinatal death or disability. No treatments exist to improve fetal growth or safely prolong pregnancy. Furthermore, wide-ranging phenotypes limit the accurate prediction of pregnancy outcome. In this issue of the JCI, Spencer and colleagues combine a discovery-science approach with ultrasound parameters to identify the most discriminative models for predicting either the primary outcome of fetal or neonatal death, or a secondary outcome of death or delivery at 28 weeks of gestation or earlier. Their findings can better individualize patient counseling but, just as compellingly, provide the capacity to identify those pregnancies that are at such considerable risk as to justify enrollment in paradigm-shifting interventional trials that are in the pipeline.

Maternal PlGF and umbilical Dopplers predict pregnancy outcomes at diagnosis of early-onset fetal growth restriction

BACKGROUNDSevere, early-onset fetal growth restriction (FGR) causes significant fetal and neonatal mortality and morbidity. Predicting the outcome of affected pregnancies at the time of diagnosis is difficult, thus preventing accurate patient counseling. We investigated the use of maternal serum protein and ultrasound measurements at diagnosis to predict fetal or neonatal death and 3 secondary outcomes: fetal death or delivery at or before 28+0 weeks, development of abnormal umbilical artery (UmA) Doppler velocimetry, and slow fetal growth.METHODSWomen with singleton pregnancies (n = 142, estimated fetal weights [EFWs] below the third centile, less than 600 g, 20+0 to 26+6 weeks of gestation, no known chromosomal, genetic, or major structural abnormalities) were recruited from 4 European centers. Maternal serum from the discovery set (n = 63) was analyzed for 7 proteins linked to angiogenesis, 90 additional proteins associated with cardiovascular disease, and 5 proteins identified through pooled liquid chromatography and tandem mass spectrometry. Patient and clinician stakeholder priorities were used to select models tested in the validation set (n = 60), with final models calculated from combined data.RESULTSThe most discriminative model for fetal or neonatal death included the EFW z score (Hadlock 3 formula/Marsal chart), gestational age, and UmA Doppler category (AUC, 0.91; 95% CI, 0.86-0.97) but was less well calibrated than the model containing only the EFW z score (Hadlock 3/Marsal). The most discriminative model for fetal death or delivery at or before 28+0 weeks included maternal serum placental growth factor (PlGF) concentration and UmA Doppler category (AUC, 0.89; 95% CI, 0.83-0.94).CONCLUSIONUltrasound measurements and maternal serum PlGF concentration at diagnosis of severe, early-onset FGR predicted pregnancy outcomes of importance to patients and clinicians.TRIAL REGISTRATIONClinicalTrials.gov NCT02097667.FUNDINGThe European Union, Rosetrees Trust, Mitchell Charitable Trust.

Rational Design of Nanomedicine for Placental Disorders: Birthing a New Era in Women's Reproductive Health

The placenta is a transient organ that forms during pregnancy and acts as a biological barrier, mediating exchange between maternal and fetal circulation. Placental disorders, such as preeclampsia, fetal growth restriction, placenta accreta spectrum, and gestational trophoblastic disease, originate in dysfunctional placental development during pregnancy and can lead to severe complications for both the mother and fetus. Unfortunately, treatment options for these disorders are severely lacking. Challenges in designing therapeutics for use during pregnancy involve selectively delivering payloads to the placenta while protecting the fetus from potential toxic side effects. Nanomedicine holds great promise in overcoming these barriers; the versatile and modular nature of nanocarriers, including prolonged circulation times, intracellular delivery, and organ-specific targeting, can control how therapeutics interact with the placenta. In this review, nanomedicine strategies are discussed to treat and diagnose placental disorders with an emphasis on understanding the unique pathophysiology behind each of these diseases. Finally, prior study of the pathophysiologic mechanisms underlying these placental disorders has revealed novel disease targets. These targets are highlighted here to motivate the rational design of precision nanocarriers to improve therapeutic options for placental disorders.

Death and severe morbidity in isolated periviable small-for-gestational-age fetuses

OBJECTIVE

This study aims to predict perinatal death or severe sequelae in isolated small-for-gestational-age fetuses, diagnosed at a periviable gestational age, based on ultrasound and Doppler parameters at diagnosis.

DESIGN

Observational study.

SETTING

A tertiary perinatal centre.

POPULATION

A cohort of singleton non-malformed fetuses suspected to be small for gestational age (estimated fetal weight, EFW, <10th centile) diagnosed at 22.0-25.6 weeks of gestation. The following parameters were recorded at diagnosis: severe smallness (<3rd centile); absent or reversed end-diastolic velocity in umbilical artery; abnormal middle cerebral artery Doppler; abnormal cerebroplacental ratio; abnormal uterine artery Doppler; and absent or reversed end-diastolic velocity in the ductus venosus.

METHODS

Logistic regression analysis.

MAIN OUTCOME MEASURES

Predictive performance of EFW and Doppler parameters for short-term adverse outcome of perinatal morbimortality and composite serious adverse outcomes (death, neurological impairment or severe bronchopulmonary dysplasia).

RESULTS

A total of 155 pregnancies were included. There were 13 (8.4%) intrauterine and 11 (7.7%) neonatal deaths. A short-term adverse perinatal outcome occurred in 40 (25.8%) pregnancies. There were 31 (20%) cases of serious adverse outcomes. For the prediction of serious adverse outcomes, the combination of absent or reversed end-diastolic velocity in the umbilical artery and impaired middle cerebral artery detected by Doppler evaluation achieved a detection rate of 87%, with a false-positive rate of 14% (accuracy 86%).

CONCLUSION

In periviable isolated small-for-gestational-age fetuses, a Doppler evaluation of the umbilical and fetal brain circulation can accurately predict short-term adverse perinatal complications and serious adverse outcomes.

Ionizable Lipid Nanoparticles for In Vivo mRNA Delivery to the Placenta during Pregnancy

Ionizable lipid nanoparticles (LNPs) are the most clinically advanced nonviral platform for mRNA delivery. While they have been explored for applications including vaccines and gene editing, LNPs have not been investigated for placental insufficiency during pregnancy. Placental insufficiency is caused by inadequate blood flow in the placenta, which results in increased maternal blood pressure and restricted fetal growth. Therefore, improving vasodilation in the placenta can benefit both maternal and fetal health. Here, we engineered ionizable LNPs for mRNA delivery to the placenta with applications in mediating placental vasodilation. We designed a library of ionizable lipids to formulate LNPs for mRNA delivery to placental cells and identified a lead LNP that enables in vivo mRNA delivery to trophoblasts, endothelial cells, and immune cells in the placenta. Delivery of this top LNP formulation encapsulated with VEGF-A mRNA engendered placental vasodilation, demonstrating the potential of mRNA LNPs for protein replacement therapy during pregnancy to treat placental disorders.

Guided cortical and cancellous bone formation using a minimally invasive technique of BMSC- and BMP-2-laden visible light-cured carboxymethyl chitosan hydrogels

A cavity defect inside the bone is formed by deformed cancellous bone from the fixation of the cortical bone, and consequently, abnormal bone healing occurs. Therefore, repairing cancellous bone defects is a remarkable topic in orthopedic surgery. In this study, we prepared bone marrow-derived stem cell (BMSC)-laden and bone morphogenetic protein-2 (BMP-2)-laden visible light-cured carboxymethyl chitosan (CMCS) hydrogels for cortical and cancellous bone healing. Proton nuclear magnetic resonance (¹H NMR) analysis confirmed the methacrylation of CMCS (CMCSMA), resulting in 55 % of substitution. The higher concentration of CMCSMA hydrogel resulted in the lower swelling ratio, the larger viscosity, the slower degradation behavior, and the stronger compressive strength. The 5 w/v% hydrogel exhibited a controlled BMP-2 release for 14 days, while the 7 and 10 w/v% hydrogels displayed a controlled BMP-2 release for 28 days. Results of in vitro cytotoxicity and cell proliferation assays revealed the biocompatibility of the samples. In vivo animal tests demonstrated that BMSC- and BMP-2-laden 7 w/v% CMCSMA (CMCSMA+Cell+BMP-2) improved bone formation in the defected cortical and cancellous bones of the femur, as analyzed by micro-computed tomography (micro-CT) and histological evaluations. Consequently, we suggested that CMCSMA+Cell+BMP-2 can be a valuable scaffold for restoring cortical and cancellous bone defects.

VEGF Expression in Umbilical Cord MSC Depends on the Patient's Health, the Week of Pregnancy in Which the Delivery Took Place, and the Body Weight of the Newborn - Preliminary Report

Introduction

Cells collected from Wharton's jelly are a rich source of mesenchymal stem cells. They can be easily obtained and grown using the adhesive method. They produce many types of proteins, including VEGF. Their role is to participate in angiogenesis, vasodilation, stimulation of cells to migrate, and chemotactic activity. The aim of this study was to evaluate expression of genes from the vascular endothelial growth factor family: VEGFA, VEGFB and VEGFC in MSC and the analysis of dependence of the expression of the studied genes on clinical factors related to the course of pregnancy and childbirth, and health of mother and child.

Material and Methods

The research material was an umbilical cord obtained from 40 patients hospitalized in the Department of Obstetrics and Pathology of Pregnancy of the Independent Public Clinical Hospital No.1 in Lublin. The age of the women was 21-46, all gave birth by cesarean section. Some of the patients suffered from hypertension and hypothyroidism. Material collected from patients immediately after delivery was subjected to enzymatic digestion with type I collagenase. The isolated cells were then cultured in adherent conditions, and then gene expression was assessed using qPCR and the immunophenotype of the cells was assessed cytometrically.

Results

Conducted studies have shown significant differences in expression of VEGF family genes depending on clinical condition of mother and child. Significant differences in VEGF-family gene expression level in umbilical cord MSC collected from women with hypothyroidism, hypertension, time of labor and birth weight of the baby were shown.

Conclusion

Probably due to hypoxia (caused, for example, by hypothyroidism or hypertension), the MSCs found in the umbilical cord may react with an increased expression of VEGF and a compensatory increase in the amount of secreted factor, the aim of which is, i.a., vasodilation and increase of blood supply to the fetus through the umbilical vessels.

Evaluation and Management of Suspected Fetal Growth Restriction

Impaired fetal growth owing to placental insufficiency is a major contributor to adverse perinatal outcomes. No intervention is available that improves outcomes by changing the pathophysiologic process. Monitoring in early-onset fetal growth restriction (FGR) focuses on optimizing the timing of iatrogenic preterm delivery using cardiotocography and Doppler ultrasound. In late-onset FGR, identifying the fetus at risk for immediate hypoxia and who benefits from expedited delivery is challenging. It is likely that studies in the next decade will provide evidence how to best integrate different monitoring variables and other prognosticators in risk models that are aimed to optimize individual treatment strategies.

Fetal Growth Restriction: Does an Integrated Maternal Hemodynamic-Placental Model Fit Better?

In recent years, a growing interest has arisen regarding the possible relationship between adverse pregnancy outcomes (APOs) and inadequate maternal hemodynamic adaptations to the pregnancy. A possible association between "placental syndromes," such as preeclampsia (PE) and fetal growth restriction (FGR), and subsequent maternal cardiovascular diseases (CVD) later in life has been reported. The two subtypes of FGR show different pathogenetic and clinical features. Defective placentation, due to a poor trophoblastic invasion of the maternal spiral arteries, is believed to play a central role in the pathogenesis of early-onset PE and FGR. Since placental functioning is dependent on the maternal cardiovascular system, a pre-existent or subsequent cardiovascular impairment may play a key role in the pathogenesis of early-onset FGR. Late FGR does not seem to be determined by a primary abnormal placentation in the first trimester. The pathological pathway of late-onset FGR may be due to a primary maternal cardiovascular maladaptation: CV system shows a flat profile and remains similar to those of non-pregnant women. Since the second trimester, when the placenta is already developed and increases its functional request, a hypovolemic state could lead to placental hypoperfusion and to an altered maturation of the placental villous tree and therefore to an altered fetal growth. Thus, this review focalizes on the possible relationship between maternal cardiac function and placentation in the development of both early and late-onset FGR. A better understanding of maternal hemodynamics in pregnancies complicated by FGR could bring various benefits in clinical practice, improving screening and therapeutic tools.

The effects of hypothyroidism and hyperthyroidism on placental Hofbauer cells of pregnant rats

We investigated the effects of maternal thyroid disorders on Hofbauer cells of both the placenta and the fetus in pregnant rats. We divided 21 rats into three groups: control group, induced hypothyroidism (hypo) group and induced hyperthyroidism (hyper) group. Hypothyroidism was induced using propylthiouracil and hyperthyroidism was induced using L-thyroxine. We measured maternal weight, maternal free thyroxine, fetal weight, fetal viability and placental morphology. At the end of the experiment, fetuses of the hypo and hyper groups were less developed than those of the control group. In the hypo and hyper groups, the thickness of the labyrinth zone was decreased, but thickness of the basal zone and decidua basalis was increased. The number of Hofbauer cells was increased in both the hypo and hyper groups. Vascular endothelial growth factor expression was increased in both the hypo and hyper groups compared to controls. Our findings indicate that maternal thyroid disorders exert a negative effect on fetal growth and placental development.

Ethical and Regulatory Considerations of Placental Therapeutics

PURPOSE

Placental therapeutics aim to treat placental disease; however, ethical and regulatory issues should be considered if the drug also potentially affects the fetus. Drugs that might transfer or edit genes carry a specific challenge because currently fetal gene editing and fetal gene therapy are considered unethical.

METHODS

This article reviews the literature on ethical and regulatory considerations for placental therapeutics.

FINDINGS

Proposals for maternal gene therapy, directed to the maternal side of the placenta, have been discussed with patients and stakeholders. No absolute ethical, legal, or regulatory barriers to this potential treatment were identified. Patients who have experienced placental disease, such as fetal growth restriction, are interested in these therapies; some would participate in first-in-human trials. Such trials need careful regulatory considerations, such as the steps required to indicate tolerability and efficacy in preclinical models and the optimal animals for reproductive toxicology studies. Ex vivo dual human placenta perfusion experiments and villous explant in vitro studies allow drugs to be tested in normal and diseased human placenta, providing short-term tolerability and toxicologic assessment. Testing drugs in nonhuman primates is an option but carries ethical and feasibility considerations. Selection of inclusion and exclusion criteria for clinical trial participants is important to ensure that the most suitable patients are exposed to a first-in-human drug. These patients will almost certainly be pregnant women with a high risk of perinatal loss and/or perinatal and maternal morbidity. Criteria should identify sufficient numbers of patients to make a trial feasible as well as a phenotype that will respond to the mechanism of action. How to dose escalate and to capture information on adverse events are also key to optimal clinical trial design.

IMPLICATIONS

Developing placental therapeutics requires input from scientists, practitioners, and regulators and close liaison with patients to ensure that new drugs are tested as carefully as possible.

Machine learning improves early prediction of small-for-gestational-age births and reveals nuchal fold thickness as unexpected predictor

OBJECTIVE

To investigate the performance of the machine learning (ML) model in predicting small-for-gestational-age (SGA) at birth, using second-trimester data.

METHODS

Retrospective data of 347 patients, consisting of maternal demographics and ultrasound parameters collected between the 20th and 25th gestational weeks, were studied. ML models were applied to different combinations of the parameters to predict SGA and severe SGA at birth (defined as 10th and third centile birth weight).

RESULTS

Using second-trimester measurements, ML models achieved an accuracy of 70% and 73% in predicting SGA and severe SGA whereas clinical guidelines had accuracies of 64% and 48%. Uterine PI (Ut PI) was found to be an important predictor, corroborating with existing literature, but surprisingly, so was nuchal fold thickness (NF). Logistic regression showed that Ut PI and NF were significant predictors and statistical comparisons showed that these parameters were significantly different in disease. Further, including NF was found to improve ML model performance, and vice versa.

CONCLUSION

ML could potentially improve the prediction of SGA at birth from second-trimester measurements, and demonstrated reduced NF to be an important predictor. Early prediction of SGA allows closer clinical monitoring, which provides an opportunity to discover any underlying diseases associated with SGA.

Adaptations of the human placenta to hypoxia: opportunities for interventions in fetal growth restriction

BACKGROUND

The placenta is the functional interface between the mother and the fetus during pregnancy, and a critical determinant of fetal growth and life-long health. In the first trimester, it develops under a low-oxygen environment, which is essential for the conceptus who has little defense against reactive oxygen species produced during oxidative metabolism. However, failure of invasive trophoblasts to sufficiently remodel uterine arteries toward dilated vessels by the end of the first trimester can lead to reduced/intermittent blood flow, persistent hypoxia and oxidative stress in the placenta with consequences for fetal growth. Fetal growth restriction (FGR) is observed in ∼10% of pregnancies and is frequently seen in association with other pregnancy complications, such as preeclampsia (PE). FGR is one of the main challenges for obstetricians and pediatricians, as smaller fetuses have greater perinatal risks of morbidity and mortality and postnatal risks of neurodevelopmental and cardio-metabolic disorders.

OBJECTIVE AND RATIONALE

The aim of this review was to examine the importance of placental responses to changing oxygen environments during abnormal pregnancy in terms of cellular, molecular and functional changes in order to highlight new therapeutic pathways, and to pinpoint approaches aimed at enhancing oxygen supply and/or mitigating oxidative stress in the placenta as a mean of optimizing fetal growth.

SEARCH METHODS

An extensive online search of peer-reviewed articles using PubMed was performed with combinations of search terms including pregnancy, placenta, trophoblast, oxygen, hypoxia, high altitude, FGR and PE (last updated in May 2020).

OUTCOMES

Trophoblast differentiation and placental establishment are governed by oxygen availability/hypoxia in early pregnancy. The placental response to late gestational hypoxia includes changes in syncytialization, mitochondrial functions, endoplasmic reticulum stress, hormone production, nutrient handling and angiogenic factor secretion. The nature of these changes depends on the extent of hypoxia, with some responses appearing adaptive and others appearing detrimental to the placental support of fetal growth. Emerging approaches that aim to increase placental oxygen supply and/or reduce the impacts of excessive oxidative stress are promising for their potential to prevent/treat FGR.

WIDER IMPLICATIONS

There are many risks and challenges of intervening during pregnancy that must be considered. The establishment of human trophoblast stem cell lines and organoids will allow further mechanistic studies of the effects of hypoxia and may lead to advanced screening of drugs for use in pregnancies complicated by placental insufficiency/hypoxia. Since no treatments are currently available, a better understanding of placental adaptations to hypoxia would help to develop therapies or repurpose drugs to optimize placental function and fetal growth, with life-long benefits to human health.

Perfluoroctanoic acid (PFOA) enhances NOTCH-signaling in an angiogenesis model of placental trophoblast cells

Exposure to perfluoroalkyl substances (PFAS) was found to be associated with several pathological endpoints, including high cholesterol levels, specific defective functions of the immune system and reduced birth weight. While environmental PFAS have been recognized as threats for public health, surprisingly little is known about the underlying mechanisms of toxicity. We hypothesized that some of the observed vascular and developmental effects of environmental PFAS may share a common molecular pathway. At elevated levels of exposure to PFAS, a reduction in mean birth weight of newborns has been observed in combination with a high incidence rate of preeclampsia. As both, preeclampsia and reduced birth weight are consequences of an inadequate placental vascularization, we hypothesized that the adaptation of placental vasculature may get compromised by PFAS. We analyzed pseudo-vascular network formation and protein expression in the HTR8/SVneo cell line, an embryonic trophoblast cell type that is able to form vessel-like vascular networks in 3D-matrices, similar to endothelial cells. PFOA (perfluoroctanoic acid), but not PFOS (perfuoroctanesulfonic acid), induced morphological changes in the vascular 3D-network structure, without indications of compromised cellular viability. Incubation with PFOA reduced cellular sprouting and elongated isolated stalks in pseudo-vascular networks, while a γ-secretase inhibitor BMS-906024 induced directional opposite effects. We found a PFOA-induced increase in NOTCH intracellular domain (NICD) abundance in HTR8/SVneo, indicating that PFOA enhances NOTCH-signaling in this cell type. Enhancement of NOTCH-pathway by PFOA may be a key to understand the mode of action of PFAS, as this pathway is critically involved in many confirmed physiological/toxicological symptoms associated with PFAS exposure.

A Transcriptome Analysis: Various Reasons of Adverse Pregnancy Outcomes Caused by Acute Toxoplasma gondii Infection

Background

Toxoplasma gondii (T. gondii) is an obligate intracellular parasite, which can affect the pregnancy outcomes in infected females by damaging the uterus, and the intrauterine environment as well as and the hypothalamus resulting in hormonal imbalance. However, the molecular mechanisms underlying the parasite-induced poor pregnancy outcomes and the key genes regulating these mechanisms remain unclear. Therefore, this study aimed to analyze the gene expression in the mouse’s uterus following experimentally-induced acute infection with T. gondii RH strain. Three groups of female mice were intraperitoneally injected with tachyzoites as follow; 3 days before pregnancy (FBD6), after pregnancy (FAD6), and after implantation (FID8) as the experimental groups. Another corresponding three groups served as control, were injected with normal saline at the same time. Transcriptome analysis of the total RNA extracted from both infected and non-infected mouse uterus samples was performed using RNA sequencing (RNA-Seq).

Results

The three experimental groups (FBD6, FAD6, and FID8) had a total of 4,561, 2,345, and 2,997 differentially expressed genes (DEGs) compared to the controls. The significantly upregulated and downregulated DEGs were 2,571 and 1,990 genes in FBD6, 1,042 and 1,303 genes in FAD6 and 1,162 and 1,835 genes in FID8 group, respectively. The analysis of GO annotation, and KEGG pathway showed that DEGs were mainly involved in anatomical structure development, transport, cell differentiation, embryo development, hormone biosynthetic process, signal transduction, immune system process, phagosome, pathways in cancer, and cytokine-cytokine receptor interaction pathways.

Conclusion

T. gondii infection can induce global transcriptomic changes in the uterus that may cause pregnancy hypertension, destruct the intrauterine environment, and hinder the normal development of placenta and embryo. Our results may help to understand the molecular mechanisms of the acute T. gondii infection, which could promote the development of new therapeutics or prophylactics for toxoplasmosis in pregnancy.

Placental bed research: II. Functional and immunological investigations of the placental bed

Research on the placenta as the interface between the mother and the fetus has been undertaken for some 150 years, and in 2 subsequent reviews, we attempted to summarize the situation. In the first part, we described the discovery of unique physiological modifications of the uteroplacental spiral arteries, enabling them to cope with a major increase in blood flow necessary to ensure proper growth of the fetus. These consist of an invasion of the arterial walls by trophoblast and a progressive disappearance of its normal structure. Researchers then turned to the pathophysiology of the placental bed and in particular to its maternal vascular tree. This yielded vital information for a better understanding of the so-called great obstetrical syndromes (preeclampsia, fetal growth restriction, premature labor and delivery, placenta accreta). Systematic morphological investigations of the uteroplacental vasculature showed that preeclampsia is associated with decreased or failed transformation of spiral arteries and the persistence of endothelial and smooth muscle cells in segments of their myometrial portion. Here we report on recent functional investigations of the placental bed, including in situ biophysical studies of uteroplacental blood flow and vascular resistance, and manipulation of uteroplacental perfusion. These new methodologies have provided a novel way of identifying pregnancies in which remodeling is impaired. In animals it is now possible to manipulate uteroplacental blood flow, leading to an enhancement of fetal growth; this opens the way to trials in abnormal human pregnancies. In this second part, we explored a new, extremely important area of research that deals with the role of specific subsets of leukocytes and macrophages in the placental bed. The human first-trimester decidua is rich in leukocytes called uterine natural killer cells. Both macrophages and uterine natural killer cells increase in number from the secretory endometrium to early pregnancy and play a critical role in mediating the process of spiral artery transformation by inducing initial structural changes. It seems therefore that vascular remodeling of spiral arteries is initiated independently of trophoblast invasion. Dysregulation of the immune system may lead to reproductive failure or pregnancy complications, and in this respect, recent studies have advanced our understanding of the mechanisms regulating immunological tolerance during pregnancy, with several mechanisms being proposed for the development of tolerance to the semiallogeneic fetus. In particular, these include several strategies by which the trophoblast avoids maternal recognition. Finally, an important new dimension is being explored: the likelihood that pregnancy syndromes and impaired uteroplacental vascular remodeling may be linked to future maternal and even the child's cardiovascular disease risk. The functional evidence underlying these observations will be discussed.

Damaging Variants in Proangiogenic Genes Impair Growth in Fetuses with Cardiac Defects

OBJECTIVE

To determine the impact of damaging genetic variation in proangiogenic pathways on placental function, complications of pregnancy, fetal growth, and clinical outcomes in pregnancies with fetal congenital heart defect.

STUDY DESIGN

Families delivering a baby with a congenital heart defect requiring surgical repair in infancy were recruited. The placenta and neonate were weighed and measured. Hemodynamic variables were recorded from a third trimester (36.4 ± 1.7 weeks) fetal echocardiogram. Exome sequencing was performed on the probands (N = 133) and consented parents (114 parent-child trios, and 15 parent-child duos) and the GeneVetter analysis tool used to identify damaging coding sequence variants in 163 genes associated with the positive regulation of angiogenesis (PRA) (GO:0045766).

RESULTS

In total, 117 damaging variants were identified in PRA genes in 133 congenital heart defect probands with 73 subjects having at least 1 variant. Presence of a damaging PRA variant was associated with increased umbilical artery pulsatility index (mean 1.11 with variant vs 1.00 without; P = .01). The presence of a damaging PRA variant was also associated with lower neonatal length and head circumference for age z score at birth (mean -0.44 and -0.47 with variant vs 0.23 and -0.05 without; P = .01 and .04, respectively). During median 3.1 years (IQR 2.0-4.1 years) of follow-up, deaths occurred in 2 of 60 (3.3%) subjects with no PRA variant and in 9 of 73 (12.3%) subjects with 1 or more PRA variants (P = .06).

CONCLUSIONS

Damaging variants in proangiogenic genes may impact placental function and are associated with impaired fetal growth in pregnancies involving a fetus with congenital heart defect.

Challenges in Designing Clinical Trials to Test New Drugs in the Pregnant Woman and Fetus

The need for new drugs in pregnancy is widely recognized. This review identifies several unique challenges and describes some solutions. Specific studies and drug development programs need careful planning that accounts for the needs of regulatory agencies. The perinatal (obstetric/pediatric) community needs to establish collaborations to develop methodologies, to facilitate data sharing, and to lobby for research and access to medicines. There is a need to gather and present information that promotes proportionate judgments of the balance between potential benefits and risks. This will require researchers to look beyond their traditional ways of working.

A systems perspective on placental amino acid transport

Placental amino acid transfer is a complex process that is essential for fetal development. Impaired amino acid transfer causes fetal growth restriction, which may have lifelong health consequences. Transepithelial transfer of amino acids across the placental syncytiotrophoblast requires accumulative, exchange and facilitated transporters on the apical and basal membranes to work in concert. However, transporters alone do not determine amino acid transfer and factors that affect substrate availability, such as blood flow and metabolism, may also become rate-limiting for transfer. In order to determine the rate-limiting processes, it is necessary to take a systems approach which recognises the interdependence of these processes. New technologies have the potential to deliver targeted interventions to the placenta and help poorly growing fetuses. While many factors are necessary for amino acid transfer, novel therapies need to target the rate-limiting factors if they are going to be effective. This review will outline the factors which determine amino acid transfer and describe how they become interdependent. It will also highlight the role of computational modelling as a tool to understand this process.

Beyond endothelial cells: Vascular endothelial growth factors in heart, vascular anomalies and placenta

Vascular endothelial growth factors regulate vascular and lymphatic growth. Dysregulation of VEGF signaling is connected to many pathological states, including hemangiomas, arteriovenous malformations and placental abnormalities. In heart, VEGF gene transfer induces myocardial angiogenesis. Besides vascular and lymphatic endothelial cells, VEGFs affect multiple other cell types. Understanding VEGF biology and its paracrine signaling properties will offer new targets for novel treatments of several diseases.