Placental Origins of Chronic Disease

Maternal cardiovascular disorders before and during pregnancy and offspring cardiovascular risk across the life course

Obesity, hypertension, type 2 diabetes mellitus and dyslipidaemia are highly prevalent among women of reproductive age and contribute to complications in >30% of pregnancies in Western countries. An accumulating body of evidence suggests that these cardiovascular disorders in women, occurring before and during their pregnancy, can affect the development of the structure, physiology and function of cardiovascular organ systems at different stages during embryonic and fetal development. These developmental adaptations might, in addition to genetics and sociodemographic and lifestyle factors, increase the susceptibility of the offspring to cardiovascular disease throughout the life course. In this Review, we discuss current knowledge of the influence of maternal cardiovascular disorders, occurring before and during pregnancy, on offspring cardiovascular development, dysfunction and disease from embryonic life until adulthood. We discuss findings from contemporary, large-scale, observational studies that provide insights into specific critical periods, evidence for causality and potential underlying mechanisms. Furthermore, we focus on priorities for future research, including defining optimal cardiovascular and reproductive health in women and men before their pregnancy and identifying specific embryonic, placental and fetal molecular developmental adaptations from early pregnancy onwards. Together, these approaches will help stop the intergenerational cycle of cardiovascular disease.

CONDITIONALLY MUTANT ANIMAL MODEL FOR INVESTIGATING THE INVASIVE TROPHOBLAST CELL LINEAGE

Placental development involves coordinated expansion and differentiation of trophoblast cell lineages possessing specialized functions. Among the differentiated trophoblast cell lineages are invasive trophoblast cells, which exit the placenta and invade into the uterus where they restructure the uterine parenchyma and facilitate remodeling of uterine spiral arteries. The rat exhibits deep intrauterine trophoblast cell invasion, a feature shared with human placentation, and is also amenable to gene manipulation using genome editing techniques. In this investigation, we generated a conditional rat model targeting the invasive trophoblast cell lineage. Prolactin family 7, subfamily b, member 1 ( Prl7b1 ) is uniquely and abundantly expressed in the rat invasive trophoblast cell lineage. Disruption of Prl7b1 did not adversely affect placental development. We demonstrated that the Prl7b1 locus could be effectively used to drive the expression of Cre recombinase in invasive trophoblast cells. Our rat model represents a new tool for investigating candidate genes contributing to the regulation of invasive trophoblast cells and their contributions to trophoblast-guided uterine spiral artery remodeling.

Vascular nitrosative stress in hypertension induced by fetal undernutrition in rats

Fetal undernutrition predisposes to hypertension development. Since nitric oxide (NO) is a key factor in blood pressure control, we aimed to investigate the role of NO alterations in hypertension induced by fetal undernutrition in rats. Male and female offspring from dams exposed to undernutrition during the second half of gestation (MUN) were studied at 21 days (normotensive) and 6 months of age (hypertension developed only in males). In aorta, we analyzed total and phosphorylated endothelial NO synthase (eNOS, p-eNOS), 3-nitrotyrosine (3-NT), and Nrf2 (Western blot). In plasma we assessed L-arginine, asymmetric and symmetric dimethylarginine (ADMA, SDMA; LC-MS/MS), nitrates (NOx, Griess reaction), carbonyl groups, and lipid peroxidation (spectrophotometry). In iliac arteries, we studied superoxide anion production (DHE staining, confocal microscopy) and vasodilatation to acetylcholine (isometric tension). Twenty-one-day-old MUN offspring did not show alterations in vascular e-NOS or 3NT expression, plasma L-Arg/ADMA ratio, or NOx. Compared to control group, 6-month-old MUN rats showed increased aortic expression of p-eNOS/eNOS and 3-NT, being Nrf2 expression lower, elevated plasma L-arginine/ADMA, NOx and carbonyl levels, increased iliac artery DHE staining and reduced acetylcholine-mediated relaxations. These alterations in MUN rats were sex-dependent, affecting males. However, females showed some signs of endothelial dysfunction. We conclude that increased NO production in the context of a pro-oxidative environment, leads to vascular nitrosative damage and dysfunction, which can participate in hypertension development in MUN males. Females show a better adaptation, but signs of endothelial dysfunction, which can explain hypertension in ageing.

Proteomic analyses of primary human villous trophoblasts exposed to flame retardant BDE-47 using SWATH-MS

Polybrominated diphenyl ethers (PBDEs) are a class of brominated flame retardants and recognized developmental toxicants that are detectable in placental tissues. Higher levels of in utero PBDE exposure have been associated with an increased risk of adverse birth outcomes. During pregnancy, cytotrophoblasts (CTBs) from the placenta play critical roles in the formation of the maternal-fetal interface via uterine invasion and vascular remodeling. The differentiation of these cells towards an invasive phenotype is crucial for proper placental development. We previously have shown that BDE-47 can impact CTB viability and hinder the ability of these cells to migrate and invade. To expand on potential toxicological mechanisms, we utilized quantitative proteomic approaches to identify changes in the global proteome of mid-gestation primary human CTBs after exposure to BDE-47. Using sequential window acquisition of all theoretical fragment-ion spectra (SWATH), we identified 3024 proteins in our CTB model of differentiation/invasion. Over 200 proteins were impacted as a function of BDE-47 exposure (1 μM and 5 μM) across the treatment period (15, 24, and 39 h). The differentially expressed molecules displayed time- and concentration-dependent changes in expression and were enriched in pathways associated with aggregatory and adhesive processes. Network analysis identified CYFIP1, a molecule previously unexplored in a placental context, to be dysregulated at BDE-47 concentrations previously seen to impact CTB migration/invasion. Our SWATH-MS dataset thus demonstrates BDE-47 impacts the global proteome of differentiating CTBs and serves as a valuable resource for further understanding of the relationship between environmental chemical exposures and placental development and function. AVAILABILITY OF DATA AND MATERIAL: Raw chromatograms are deposited on the MassIVE proteomic database (https://massive.ucsd.edu) under accession number MSV000087870. Normalized relative abundances are also available as Table S1.

Epigenome-Wide Associations of Placental DNA Methylation and Behavioral and Emotional Difficulties in Children at 3 Years of Age

The placenta is a key organ for fetal and brain development. Its epigenome can be regarded as a biochemical record of the prenatal environment and a potential mechanism of its association with the future health of the fetus. We investigated associations between placental DNA methylation levels and child behavioral and emotional difficulties, assessed at 3 years of age using the Strengths and Difficulties Questionnaire (SDQ) in 441 mother-child dyads from the EDEN cohort. Hypothesis-driven and exploratory analyses (on differentially methylated probes (EWAS) and regions (DMR)) were adjusted for confounders, technical factors, and cell composition estimates, corrected for multiple comparisons, and stratified by child sex. Hypothesis-driven analyses showed an association of cg26703534 (AHRR) with emotional symptoms, and exploratory analyses identified two probes, cg09126090 (intergenic region) and cg10305789 (PPP1R16B), as negatively associated with peer relationship problems, as well as 33 DMRs, mostly positively associated with at least one of the SDQ subscales. Among girls, most associations were seen with emotional difficulties, whereas in boys, DMRs were as much associated with emotional than behavioral difficulties. This study provides the first evidence of associations between placental DNA methylation and child behavioral and emotional difficulties. Our results suggest sex-specific associations and might provide new insights into the mechanisms of neurodevelopment.

Assisted reproductive technology (ART) and epigenetic modifications in the placenta

Assisted reproductive technology (ART) has become common amongst couples with infertility issues. ART is known to be successful, but epidemiological data indicates that ART is associated with placental disorders. Additionally, reports show increased risks of short- and long-term complications in children born to mothers undergoing ART. However, the mechanisms responsible for these events are obscure. The placenta is considered as a key organ for programming of diseases and ART procedures are suggested to alter the placental function and intrauterine growth trajectories. Epigenetic changes in maternal and foetal tissues are suggested to be the underlying mechanisms for these outcomes. Epigenetic regulation is known to evolve following fertilisation and before implantation and subsequently across gestation. During these critical periods of epigenetic 'programming', DNA methylation and chromatin remodelling influence the placental structure and function by regulating the expression of various genes. ART treatment coinciding with epigenetic 'programming' events during gametogenesis and early embryo development may alter the programming phases leading to long-term consequences. Thus, disruptions in placental development observed in ART pregnancies could be associated with altered epigenetic regulation of vital genes in the placenta. The review summarises available literature on the influence of ART procedures on epigenetic changes in the placenta.

Maternal obesity alters the placental transcriptome in a fetal sex-dependent manner

Infants born to obese mothers have an increased risk of developing obesity and metabolic diseases in childhood and adulthood. Although the molecular mechanisms linking maternal obesity during pregnancy to the development of metabolic diseases in offspring are poorly understood, evidence suggests that changes in the placental function may play a role. Using a mouse model of diet-induced obesity with fetal overgrowth, we performed RNA-seq analysis at embryonic day 18.5 to identify genes differentially expressed in the placentas of obese and normal-weight dams (controls). In male placentas, 511 genes were upregulated and 791 genes were downregulated in response to maternal obesity. In female placentas, 722 genes were downregulated and 474 genes were upregulated in response to maternal obesity. The top canonical pathway downregulated in maternal obesity in male placentas was oxidative phosphorylation. In contrast, sirtuin signaling, NF-kB signaling, phosphatidylinositol, and fatty acid degradation were upregulated. In female placentas, the top canonical pathways downregulated in maternal obesity were triacylglycerol biosynthesis, glycerophospholipid metabolism, and endocytosis. In contrast, bone morphogenetic protein, TNF, and MAPK signaling were upregulated in the female placentas of the obese group. In agreement with RNA-seq data, the expression of proteins associated with oxidative phosphorylation was downregulated in male but not female placentas of obese mice. Similarly, sex-specific changes in the protein expression of mitochondrial complexes were found in placentas collected from obese women delivering large-for-gestational-age (LGA) babies. In conclusion, maternal obesity with fetal overgrowth differentially regulates the placental transcriptome in male and female placentas, including genes involved in oxidative phosphorylation.

Associations between the maternal healthy lifestyle score and its individual components during early pregnancy with placental outcomes

INTRODUCTION

The influence of maternal lifestyle behaviours on placental growth have been investigated individually, but with conflicting results, and their combined effect is under-researched. Therefore, we examined associations between a composite maternal healthy lifestyle score (HLS), and its individual components, during early pregnancy with placental outcomes.

METHODS

Participants included Lifeways Cross-Generational Cohort mother-child pairs (n = 202). A composite HLS based on a less inflammatory diet (bottom 40% of the energy-adjusted Dietary Inflammatory Index (E-DII™)), moderate-to-vigorous physical activity (MVPA), healthy pre-pregnancy BMI (18.5-24.9 kg/m²), never smoking, and non-/moderate alcohol intake was calculated. Quantile regression analysed HLS (and individual components) associations with measures of placental development (untrimmed placental weight (PW)) and function (birth weight:placental weight (BW:PW) ratio) at the 10th, 25th, 50th, 75th and 90th centiles.

RESULTS

A more pro-inflammatory diet was positively, and smoking and heavy alcohol consumption were negatively, associated with PW at median centiles (B: 41.97 g, CI: 3.71, 80.22, p < 0.05; B: -58.51 g, CI: -116.24, -0.77, p < 0.05; B: -120.20 g, CI: -177.97, -62.43, p < 0.05 respectively). Low MVPA was inversely associated with BW:PW ratio at the 10th and 90th centiles (B: -0.36, CI: -0.132, -0.29, p < 0.01 and B: -0.45, CI: -0.728, -0.182, p < 0.01, respectively). Heavy alcohol intake was positively associated with BW:PW ratio at the 10th centile (B: 0.54, CI: 0.24, 0.85, p < 0.01). Results of sex-stratified analysis provide evidence of sexual dimorphism.

DISCUSSION

Associations of certain lifestyle factors, but not the composite HLS, during early pregnancy with measures of placental development (PW) and function (BW:PW ratio) varied by quantiles and by sex.

Establishment of the fetal-maternal interface: developmental events in human implantation and placentation

Early pregnancy is a complex and well-orchestrated differentiation process that involves all the cellular elements of the fetal-maternal interface. Aberrant trophoblast-decidual interactions can lead to miscarriage and disorders that occur later in pregnancy, including preeclampsia, intrauterine fetal growth restriction, and preterm labor. A great deal of research on the regulation of implantation and placentation has been performed in a wide range of species. However, there is significant species variation regarding trophoblast differentiation as well as decidual-specific gene expression and regulation. Most of the relevant information has been obtained from studies using mouse models. A comprehensive understanding of the physiology and pathology of human implantation and placentation has only recently been obtained because of emerging advanced technologies. With the derivation of human trophoblast stem cells, 3D-organoid cultures, and single-cell analyses of differentiated cells, cell type-specific transcript profiles and functions were generated, and each exhibited a unique signature. Additionally, through integrative transcriptomic information, researchers can uncover the cellular dysfunction of embryonic and placental cells in peri-implantation embryos and the early pathological placenta. In fact, the clinical utility of fetal-maternal cellular trafficking has been applied for the noninvasive prenatal diagnosis of aneuploidies and the prediction of pregnancy complications. Furthermore, recent studies have proposed a viable path toward the development of therapeutic strategies targeting placenta-enriched molecules for placental dysfunction and diseases.

The ethanolic extract of Salvia lachnostachys Benth is not maternotoxic, does not alter reproductive performance, but has teratogenic potential

Salvia lachnostachys Benth is native to Brazil and has anti-inflammatory, anti-arthritic, cytotoxic, antitumor, and antihyperalgesic activities. The population, including pregnant women, consume this plant to treat pain, inflammation, flu, spasms, insomnia, and depression, mainly. There are no safety reports on the use of this plant during pregnancy. The present study aimed to evaluate the effects of S. lachnostachys ethanolic extract (EESl) on reproductive performance, embryofetal development, and DNA integrity of pregnant female mice. Pregnant females were randomly divided into three experimental groups (n = 10): The Control group was treated with a vehicle, and treatment groups were administered with EESl at 100 and 1000 mg/kg, respectively. Treatment occurred by gavage throughout the gestational period until day 18. Afterward, reproductive performance, embryofetal development, and DNA integrity parameters were evaluated. The results indicated that EESl did not alter any reproductive performance parameters. However, it changed embryofetal outcome through reduced placental weight (EESl 100 mg/kg), decreased fetal weight (EESl 100 and 1000 mg/kg), and increased frequency of small for gestational age fetuses (EESl 1000 mg/kg). In addition, EES1 increased the frequency of external, visceral, and skeletal malformations. Because of the above, it is considered that EESl is not maternotoxic, does not alter reproductive performance, but does alter embryofetal development. Its use in the gestational period is not indicated due to its teratogenic potential.

Perinatal mortality rate and adverse perinatal outcomes presumably attributable to placental dysfunction in (near) term gestation: A nationwide 5-year cohort study

INTRODUCTION

Placental dysfunction can lead to perinatal hypoxic events including stillbirth. Unless there is overt severe fetal growth restriction, placental dysfunction is frequently not identified in (near) term pregnancy, particularly because fetal size is not necessarily small. This study aimed to evaluate, among (near) term births, the burden of hypoxia-related adverse perinatal outcomes reflected in an association with birth weight centiles as a proxy for placental function.

MATERIAL AND METHOD

A nationwide 5-year cohort of the Dutch national birth registry (PeriNed) including 684,938 singleton pregnancies between 36+0 and 41+6 weeks of gestation. Diabetes, congenital anomalies, chromosomal abnormalities and non-cephalic presentations at delivery were excluded. The main outcome was antenatal mortality rate according to birthweight centiles and gestational age. Secondary outcomes included perinatal hypoxia-related outcomes, including perinatal death and neonatal morbidity, analyzed according to birthweight centiles.

RESULTS

Between 2015 and 2019, 1,074 perinatal deaths (0.16%) occurred in the study population (n = 684,938), of which 727 (0.10%) antenatally. Of all antenatal- and perinatal deaths, 29.4% and 27.9% occurred in birthweights below the 10th centile. The incidence of perinatal hypoxia-related outcomes was highest in fetuses with lowest birthweight centiles (18.0%), falling gradually up to the 50th and 90th centile where the lowest rates of hypoxia-related outcomes (5.4%) were observed.

CONCLUSION

Perinatal hypoxia-related events have the highest incidence in the lowest birthweight centiles but are identifiable throughout the entire spectrum. In fact, the majority of the adverse outcome burden in absolute numbers occurs in the group with a birthweight above the 10th centile. We hypothesize that in most cases these events are attributable to reduced placental function. Additional diagnostic modalities that indicate placental dysfunction at (near) term gestation throughout all birth weight centiles are eagerly wanted.

Associations between prenatal organophosphate pesticide exposure and placental gene networks

BACKGROUND

Exposure to organophosphate (OP) pesticides during pregnancy has been linked to deficiencies of neurobehavioral development in childhood; however, the molecular mechanisms underlying this association remain elusive. The placenta plays a crucial role in protecting the fetus from environmental insults and safeguarding proper fetal development including neurodevelopment. The aim of our study is to evaluate changes in the placental transcriptome associated with prenatal OP exposure.

METHODS

Pregnant farm workers from two agricultural districts in northern Thailand were recruited for the Study of Asian Women and Offspring's Development and Environmental Exposures (SAWASDEE) from 2017 to 2019. For 254 participants, we measured maternal urinary concentrations of six nonspecific dialkyl phosphates (DAP) metabolites in early, middle, and late pregnancy. In parallel, we profiled the term placental transcriptome from the same participants using RNA-Sequencing and performed Weighted Gene co-expression Network Analysis (WGCNA). Generalized linear regression modeling was used to examine associations of urinary OP metabolites and placental co-expression module eigenvalues.

RESULTS

We identified 21 gene co-expression modules in the placenta. From the six DAP metabolites assayed, diethylphosphate (DEP) and diethylthiophosphate (DETP) were detected in more than 70% of the urine samples. Significant associations between DEP at multiple time points and two specific placental gene modules were observed. The 'black' module, enriched in genes involved in epithelial-to-mesenchymal transition (EMT) and hypoxia, was negatively associated with DEP in early (p = 0.034), and late pregnancies (p = 0.016). The 'lightgreen' module, enriched in genes involved in myogenesis and EMT, was negatively associated with DEP in late pregnancy (p = 0.010). We observed 2 hub genes (CELSR1 and PYCR1) of the 'black' module to be negatively associated with DEP in early and late pregnancies.

CONCLUSIONS

Our results suggest that prenatal OP exposure may disrupt placental gene networks in a time-dependent manner. Such transcriptomic effects may lead to down-stream changes in placental function that ultimately affect the developing fetus.

Placental levels of essential and non-essential trace element in relation to neonatal weight in Northwestern Spain: application of generalized additive models

Adequate gestational progression depends to a great extent on placental development, which can modify maternal and neonatal outcomes. Any environmental toxicant, including metals, with the capacity to affect the placenta can alter the development of the pregnancy and its outcome. The objective of this study was to correlate the placenta levels of 14 essential and non-essential elements with neonatal weight. We examined relationships between placental concentrations of arsenic, cadmium, cobalt, copper, mercury, lithium, manganese, molybdenum, nickel, lead, rubidium, selenium, strontium, and zinc from 79 low obstetric risk pregnant women in Ourense (Northwestern Spain, 42°20'12.1″N 7°51.844'O) with neonatal weight. We tested associations between placental metal concentrations and neonatal weight by conducting multivariable linear regressions using generalized linear models (GLM) and generalized additive models (GAM). While placental Co (p = 0.03) and Sr (p = 0.048) concentrations were associated with higher neonatal weight, concentrations of Li (p = 0.027), Mo (p = 0.049), and Se (p = 0.02) in the placenta were associated with lower newborn weight. Our findings suggest that the concentration of some metals in the placenta may affect fetal growth.

The human placenta: new perspectives on its formation and function during early pregnancy

The placenta has evolved to support the development of the embryo and fetus during the different intrauterine periods of life. By necessity, its development must precede that of the embryo. There is now evidence that during embryogenesis and organogenesis, the development of the human placenta is supported by histotrophic nutrition secreted from endometrial glands rather than maternal blood. These secretions provide a plentiful supply of glucose, lipids, glycoproteins and growth factors that stimulate rapid proliferation and differentiation of the villous trophoblast. Furthermore, evidence from endometrial gland organoids indicates that expression and secretion of these products are upregulated following sequential exposure to oestrogen, progesterone and trophoblastic and decidual hormones, in particular prolactin. Hence, a feed-forward signalling dialogue is proposed among the trophoblast, decidua and glands that enables the placenta to stimulate its own development, independent of that of the embryo. Many common complications of pregnancy represent a spectrum of disorders associated with deficient trophoblast proliferation. Increasing evidence suggests that this spectrum is mirrored by one of impaired decidualization, potentially compromising histotroph secretion through diminished prolactin secretion and reduced gland function. Optimizing endometrial wellbeing prior to conception may therefore help to prevent common pregnancy complications, such as miscarriage, growth restriction and pre-eclampsia.

Integrated Placental Modelling of Histology with Gene Expression to Identify Functional Impact on Fetal Growth

Fetal growth restriction (FGR) is a leading cause of perinatal morbidity and mortality. Altered placental formation and functional capacity are major contributors to FGR pathogenesis. Relating placental structure to function across the placenta in healthy and FGR pregnancies remains largely unexplored but could improve understanding of placental diseases. We investigated integration of these parameters spatially in the term human placenta using predictive modelling. Systematic sampling was able to overcome heterogeneity in placental morphological and molecular features. Defects in villous development, elevated fibrosis, and reduced expression of growth and functional marker genes (IGF2, VEGA, SLC38A1, and SLC2A3) were seen in age-matched term FGR versus healthy control placentas. Characteristic histopathological changes with specific accompanying molecular signatures could be integrated through computational modelling to predict if the placenta came from a healthy or FGR pregnancy. Our findings yield new insights into the spatial relationship between placental structure and function and the etiology of FGR.

Distinct Changes in Placental Ceramide Metabolism Characterize Type 1 and 2 Diabetic Pregnancies with Fetal Macrosomia or Preeclampsia

Disturbances of lipid metabolism are typical in diabetes. Our objective was to characterize and compare placental sphingolipid metabolism in type 1 (T1D) and 2 (T2D) diabetic pregnancies and in non-diabetic controls. Placental samples from T1D, T2D, and control pregnancies were processed for sphingolipid analysis using tandem mass spectrometry. Western blotting, enzyme activity, and immunofluorescence analyses were used to study sphingolipid regulatory enzymes. Placental ceramide levels were lower in T1D and T2D compared to controls, which was associated with an upregulation of the ceramide degrading enzyme acid ceramidase (ASAH1). Increased placental ceramide content was found in T1D complicated by preeclampsia. Similarly, elevated ceramides were observed in T1D and T2D pregnancies with poor glycemic control. The protein levels and activity of sphingosine kinases (SPHK) that produce sphingoid-1-phosphates (S1P) were highest in T2D. Furthermore, SPHK levels were upregulated in T1D and T2D pregnancies with fetal macrosomia. In vitro experiments using trophoblastic JEG3 cells demonstrated increased SPHK expression and activity following glucose and insulin treatments. Specific changes in the placental sphingolipidome characterize T1D and T2D placentae depending on the type of diabetes and feto-maternal complications. Increased exposure to insulin and glucose is a plausible contributor to the upregulation of the SPHK-S1P-axis in diabetic placentae.

Effect of birth rank, and placentome subtype on expression of genes involved in placental nutrient transport in sheep

Placental function is a key determinant of fetal growth and development that can be influenced by maternal and fetal environmental factors. The molecular mechanisms by which the placenta senses and responds to environmental cues are poorly understood. This exploratory study aimed to characterize the effect of birth rank (single vs. twin) and placentome morphologic subtype on expression of genes involved in nutrient transport, angiogenesis, immunity and stress response. Cotyledonary tissue was collected from type A, B and C placentomes from five single and six twin fetuses at 140 days of gestation. GLUT1 and GLUT3 were the most highly expressed genes consistent with the high demand for glucose to support fetal growth. Expression of BCKDHβ and IGF-2 was 1.3- and 1.5-fold higher, respectively, and PCYT1A was 3-fold lower in singles compared to twins (P < 0.05) while no other differences in gene expression were observed between birth ranks. Expression of EAAT2 and LAT2 was higher while PCYT1A was lower in A compared to B type cotyledons. Expression of GUCY1B1/3 and IGF-1 was higher while CD98 and LAT2 were lower in type B compared to C cotyledons (P < 0.05). Compared to type C cotyledons, expression of EAAT2, IGF-1, IGF-2, LAT1 was higher, while TEK was lower in type A cotyledons. The effects of birth rank on placental gene expression in this study indicated that placental nutrient transport and/or function differs between single and twin pregnancies in sheep. Differences in gene expression between the placentome subtypes suggests that changes in placentome morphology are associated with shifts in amino acid transport and metabolism, oxidative stress and angiogenesis and/or blood flow. This study highlights that placental gene expression differs in response to birth rank and placentome morphologic subtype which suggests that both maternal and fetal factors may influence placental function in sheep. These associations provide insights into gene pathways for more targeted future investigations as well as potential adaptations to improve placental efficiency to support fetal growth in twin pregnancies.

Targeting first trimester trophoblast cell metabolism modulates its susceptibility to Zika virus infection

In the last 15 years Zika virus (ZIKV) caused several outbreaks of increasing scale in Micronesia, South Pacific islands, and more recently in the Caribbean and South America. The severity of the clinical presentation in neonates from pregnant women infected with ZIKV during the last outbreak supports the relevance of unraveling the mechanism of infection and viral persistence in the placenta with local viral isolates. Here, we investigated the relevance of trophoblast metabolic rewiring for viral multiplication and the role of the vasoactive intestinal peptide (VIP) as an endogenous factor associated with placental restriction to ZIKV infection at early pregnancy. Our in vitro model demonstrated that ZIKV triggers metabolic rewiring in first trimester cytotrophoblast-derived cells by increasing glucose utilization as fuel to sustain its replication, decreasing long-chain polyunsaturated fatty acid uptake, and promoting lipid droplets accumulation to favor its multiplication. Of note, variations in nutrient availability modulated viral spread in trophoblast cultures. The presence of VIP during trophoblast infection impaired ZIKV infective particle production and viral replication, restoring cell migration and metabolism. Moreover, the blockade of endogenous VIP signaling increased viral particle production and the viral entry receptor AXL expression. These results highlight the potential role of VIP as an endogenous antiviral factor related to trophoblast cell permissiveness to ZIKV infection at early pregnancy.

Targeted bisulfite resequencing of differentially methylated cytosines in pre-eclampsia reveals a skewed dynamic balance in the DNA methylation of enhancers

Pre-eclampsia (PE) is a major hypertensive disorder of pregnancy. Widespread differentially methylated cytosines (DMCs) with modest changes in methylation level are associated with PE, whereas their cause and biological significance remain unknown. We aimed to clarify DNA methylation patterns around DMCs in 103 placentas using MethylCap targeted bisulfite re-sequencing (MethylCap-seq) assays of 690 selected DMCs. We verified the MethylCap-seq method, then validated 677 (98.1%) of DMCs (vDMCs) in an independent cohort. The validated DMCs were strongly enriched in active placenta-specific enhancers and showed highly dynamic methylation levels. We found high epigenetic heterogeneity between vDMCs and adjacent CpG sites (r2 < 0.2) and a significant decrease in PE in the discovery and replication cohorts (P = 2.00 × 10-24 and 6.43 × 10-9, respectively). We replicated the methylation changes in a hypoxia/reoxygenation cell model. We constructed 112 methylation haplotype blocks and found that the frequencies of unmethylated haplotypes (UMHs) were dynamic with gestational age (GA) and were altered in maternal plasma of patients with PE. Our results uncovered additional DNA methylation features in PE placentas and suggested a model of skewed DNA methylation balance of enhancers in PE.

Pan-Genomic Regulation of Gene Expression in Normal and Pathological Human Placentas

In this study, we attempted to find genetic variants affecting gene expression (eQTL = expression Quantitative Trait Loci) in the human placenta in normal and pathological situations. The analysis of gene expression in placental diseases (Pre-eclampsia and Intra-Uterine Growth Restriction) is hindered by the fact that diseased placental tissue samples are generally taken at earlier gestations compared to control samples. The difference in gestational age is considered a major confounding factor in the transcriptome regulation of the placenta. To alleviate this significant problem, we propose here a novel approach to pinpoint disease-specific cis-eQTLs. By statistical correction for gestational age at sampling as well as other confounding/surrogate variables systematically searched and identified, we found 43 e-genes for which proximal SNPs influence expression level. Then, we performed the analysis again, removing the disease status from the covariates, and we identified 54 e-genes, 16 of which are identified de novo and, thus, possibly related to placental disease. We found a highly significant overlap with previous studies for the list of 43 e-genes, validating our methodology and findings. Among the 16 disease-specific e-genes, several are intrinsic to trophoblast biology and, therefore, constitute novel targets of interest to better characterize placental pathology and its varied clinical consequences. The approach that we used may also be applied to the study of other human diseases where confounding factors have hampered a better understanding of the pathology.

Developmental Ultrasound Characteristics in Guinea Pigs: Similarities with Human Pregnancy

BACKGROUND

Biometrical and blood flow examinations are fundamental for assessing fetoplacental development during pregnancy. Guinea pigs have been proposed as a good model to study fetal development and related gestational complications; however, longitudinal growth and blood flow changes in utero have not been properly described. This study aimed to describe fetal and placental growth and blood flow of the main intrauterine vascular beds across normal guinea pig pregnancy and to discuss the relevance of this data for human pregnancy.

METHODS

Pregnant guinea pigs were studied from day 25 of pregnancy until term (day ~70) by ultrasound and Doppler assessment. The results were compared to human data from the literature.

RESULTS

Measurements of biparietal diameter (BPD), cranial circumference (CC), abdominal circumference, and placental biometry, as well as pulsatility index determination of umbilical artery, middle cerebral artery (MCA), and cerebroplacental ratio (CPR), were feasible to determine across pregnancy, and they could be adjusted to linear or nonlinear functions. In addition, several of these parameters showed a high correlation coefficient and could be used to assess gestational age in guinea pigs. We further compared these data to ultrasound variables from human pregnancy with high similarities.

CONCLUSIONS

BPD and CC are the most reliable measurements to assess fetal growth in guinea pigs. Furthermore, this is the first report in which the MCA pulsatility index and CPR are described across guinea pig gestation. The guinea pig is a valuable model to assess fetal growth and blood flow distribution, variables that are comparable with human pregnancy.

Gestational Diabetes Mellitus Impedes Fetal Lung Development Through Exosome-Dependent Crosstalk Between Trophoblasts and Lung Epithelial Cells

Background

Fetal lung underdevelopment (FLUD) is associated with neonatal and childhood severe respiratory diseases, among which gestational diabetes mellitus (GDM) play crucial roles as revealed by recent prevalence studies, yet mechanism underlying GDM-induced FLUD, especially the role of trophoblasts, is not all known.

Methods

From the perspective of trophoblast-derived exosomes, we established in vitro, ex vivo, in vivo and GDM trophoblast models. Utilizing placenta-derived exosomes (NUB-exos and GDMUB-exos) isolated from normal and GDM umbilical cord blood plasma and trophoblast-derived exosomes (NC-exos and HG-exos) isolated from HTR8/SVneo trophoblasts medium with/without high glucose treatment, we examined their effects on fetal lung development and biological functions.

Results

We found that, compared with the NUB-exos group, the exosome concentration increased in GDMUB-exos group, and the content of exosomes also changed evidenced by 61 dysregulated miRNAs. After applying these exosomes to A549 alveolar type II epithelial cells, the proliferation and biological functions were suppressed while the proportion of apoptotic cells was increased as compared to the control. In ex vivo studies, we found that GDMUB-exos showed significant suppression on the growth of the fetal lung explants, where the number of terminal buds and the area of explant surface decreased and shrank. Besides, the expression of Fgf10, Vegfa, Flt-1, Kdr and surfactant proteins A, B, C, and D was downregulated in GDMUB-exos group, whilst Sox9 was upregulated. For in vivo studies, we found significant suppression of fetal lung development in GDMUB-exos group. Importantly, we found consistent alterations when we used NC-exos and HG-exos, suggesting a dominant role of trophoblasts in placenta-derived exosome-induced FLUD.

Conclusion

In conclusion, GDM can adversely affect trophoblasts and alter exosome contents, causing crosstalk disorder between trophoblasts and fetal lung epithelial cells and finally leading to FLUD. Findings of this study will shine insight into the theoretical explanation for the pathogenesis of FLUD.

Placental pathology is necessary to understand common pregnancy complications and achieve an improved taxonomy of obstetrical disease

The importance of a fully functioning placenta for a good pregnancy outcome is unquestioned. Loss of function can lead to pregnancy complications and is often detected by a thorough placental pathologic examination. Placental pathology has advanced the science and practice of obstetrics and neonatal-perinatal medicine by classifying diseases according to underlying biology and specific patterns of injury. Many past obstacles have limited the incorporation of placental findings into both clinical studies and day-to-day practice. Limitations have included variability in the nomenclature used to describe placental lesions, a shortage of perinatal pathologists fully competent to analyze placental specimens, and a troubling lack of understanding of placental diagnoses by clinicians. However, the potential use of placental pathology for phenotypic classification, improved understanding of the biology of adverse pregnancy outcomes, the development of treatment and prevention, and patient counseling has never been greater. This review, written partly in response to a recent critique published in a major obstetrics-gynecology journal, reexamines the role of placental pathology by reviewing current concepts of biology; explaining the most recent terminology; emphasizing the usefulness of specific diagnoses for obstetrician-gynecologists, neonatologists, and patients; previewing upcoming changes in recommendations for placental submission; and suggesting future improvements. These improvements should include further consideration of overall healthcare costs, cost-effectiveness, the clinical value added of placental assessment, improvements in placental pathology education and practice, and leveraging of placental pathology to identify new biomarkers of disease and evaluate novel therapies tailored to specific clinicopathologic phenotypes of both women and infants.

Placental F4-Neuroprostanes and F2-Isoprostanes are altered in gestational diabetes mellitus and maternal obesity

We investigated whether gestational diabetes mellitus (GDM) associated with maternal obesity modifies the placental profile of F₄-Neuroprostanes and F₂-Isoprostanes, metabolites of non-enzymatic oxidation of docosahexaenoic acid (DHA) and arachidonic acid (AA), respectively. Twenty-five placental samples were divided into lean (n=11), obesity (n=7) and overweight/obesity+GDM (n=7) groups. F₄-Neuroprostanes and F₂-Isoprostanes were higher in obesity compared to lean controls, but reduced to levels similar to lean women when obesity is further complicated with GDM. Lower content of F₂-Isoprostanes suggests adaptive placental responses in GDM attenuating oxidative stress. However, low levels of placental F₄-Neuroprostanes may indicate impaired DHA metabolism in GDM, affecting fetal development and offspring health. These results were not related to differences in placental content of DHA, AA and polyunsaturated fatty acids status nor to maternal diet or gestational weight gain. Placental DHA and AA metabolism differs in obesity and GDM, highlighting the importance of investigating the signalling roles of F₄-Neuroprostanes and F₂-Isoprostanes in the human term placenta.

Imbalance of Angiogenic and Growth Factors in Placenta in Maternal Hyperhomocysteinemia

Numerous studies have shown that various adverse factors of different nature and action mechanisms have similar negative influence on placental angiogenesis, resulting in insufficiency of placental blood supply. One of the risk factors for pregnancy complications with placental etiology is an increased level of homocysteine in the blood of pregnant women. However, the effect of hyperhomocysteinemia (HHcy) on the development of the placenta and, in particular, on the formation of its vascular network is at present poorly understood. The aim of this work was to study the effect of maternal HHcy on the expression of angiogenic and growth factors (VEGF-A, MMP-2, VEGF-B, BDNF, NGF), as well as their receptors (VEGFR-2, TrkB, p75NTR), in the rat placenta. The effects of HHcy were studied in the morphologically and functionally different maternal and fetal parts of the placenta on the 14th and 20th day of pregnancy. The maternal HHcy caused increase in the levels of oxidative stress and apoptosis markers accompanied by an imbalance of the studied angiogenic and growth factors in the maternal and/or fetal part of the placenta. The influence of maternal HHcy in most cases manifested in a decrease in the protein content (VEGF-A), enzymatic activity (MMP-2), gene expression (VEGFB, NGF, TRKB), and accumulation of precursor form (proBDNF) of the investigated factors. In some cases, the effects of HHcy differed depending on the placental part and stage of development. The influence of maternal HHcy on signaling pathways and processes controlled by the studied angiogenic and growth factors could lead to incomplete development of the placental vasculature and decrease in the placental transport, resulting in fetal growth restriction and impaired fetal brain development.

Developmental toxicity and programming alterations of multiple organs in offspring induced by medication during pregnancy

Medication during pregnancy is widespread, but there are few reports on its fetal safety. Recent studies suggest that medication during pregnancy can affect fetal morphological and functional development through multiple pathways, multiple organs, and multiple targets. Its mechanisms involve direct ways such as oxidative stress, epigenetic modification, and metabolic activation, and it may also be indirectly caused by placental dysfunction. Further studies have found that medication during pregnancy may also indirectly lead to multi-organ developmental programming, functional homeostasis changes, and susceptibility to related diseases in offspring by inducing fetal intrauterine exposure to too high or too low levels of maternal-derived glucocorticoids. The organ developmental toxicity and programming alterations caused by medication during pregnancy may also have gender differences and multi-generational genetic effects mediated by abnormal epigenetic modification. Combined with the latest research results of our laboratory, this paper reviews the latest research progress on the developmental toxicity and functional programming alterations of multiple organs in offspring induced by medication during pregnancy, which can provide a theoretical and experimental basis for rational medication during pregnancy and effective prevention and treatment of drug-related multiple fetal-originated diseases.

Preconception paternal alcohol exposure decreases IVF embryo survival and pregnancy success rates in a mouse model

Increasingly, couples struggling with fertility turn to assisted reproductive techniques, including IVF, to have children. Despite the demonstrated influence of periconception male health and lifestyle choices on offspring development, studies examining IVF success rates and child health outcomes remain exclusively focused on maternal factors. Using a physiologically relevant mouse model, we tested the hypothesis that chronic paternal preconception alcohol intake adversely affects IVF success and negatively impacts IVF offspring fetoplacental growth. Using a voluntary, binge-like mouse model, we exposed sexually mature C57BL/6J males to three preconception treatments (0% (Control), 6% EtOH or 10% EtOH) for 6 weeks, isolated and cryopreserved caudal sperm from treated males, and then used these samples to fertilize oocytes before assessing IVF embryo developmental outcomes. We found that preconception paternal alcohol use reduced IVF embryo survival and pregnancy success rates in a dose-dependent manner, with the pregnancy success rate of the 10% EtOH treatment falling to half those of the Controls. Mechanistically, we found that preconception paternal alcohol exposure disrupts embryonic gene expression, including Fgf4 and Egfr, two critical regulators of trophectoderm stem cell growth and placental patterning, with lasting impacts on the histological organization of the late-term placenta. The changes in placental histoarchitecture were accompanied by altered regulation of pathways controlling mitochondrial function, oxidative phosphorylation and some imprinted genes. Our studies indicate that male alcohol use may significantly impede IVF success rates, increasing the couple's financial burden and emotional stress, and highlights the need to expand prepregnancy messaging to emphasize the reproductive dangers of alcohol use by both parents.

Placental Changes and Neuropsychological Development in Children-A Systematic Review

Placental dysfunction may increase the offspring's later-life disease risk. The objective of this systematic review was to describe associations between pathological placental changes and neuropsychological outcomes in children after the neonatal period. The inclusion criteria were human studies; original research; direct placental variables; neuropsychological outcomes; and analysis between their associations. The exclusion criterion was the offspring's age-0-28 days or >19 years. The MEDLINE and EMBASE databases were last searched in May 2022. We utilized the ROBINS-I for the risk of bias assessment and performed a narrative synthesis. In total, 3252 studies were identified, out of which 16 were included (i.e., a total of 15,862 participants). Half of the studies were performed on children with neonatal complications, and 75% of the studies reported an association between a placental change and an outcome; however, following the completion of the funnel plots, a risk of publication bias was indicated. The largest study described a small association between placental size and a risk of psychiatric symptoms in boys only. Inconsistency between the studies limited the evidence in this review. In general, no strong evidence was found for an association between pathological placental changes and childhood neuropsychological outcomes after the neonatal period. However, the association between placental size and mental health in boys indicates a placental sexual dimorphism, thereby suggesting an increased vulnerability for male fetuses.

CITED2 is a conserved regulator of the uterine-placental interface

Establishment of the hemochorial uterine-placental interface requires exodus of trophoblast cells from the placenta and their transformative actions on the uterus, which represent processes critical for a successful pregnancy, but are poorly understood. We examined the involvement of CBP/p300-interacting transactivator with glutamic acid/aspartic acid-rich carboxyl-terminal domain 2 (CITED2) in rat and human trophoblast cell development. The rat and human exhibit deep hemochorial placentation. CITED2 was distinctively expressed in the junctional zone (JZ) and invasive trophoblast cells of the rat. Homozygous Cited2 gene deletion resulted in placental and fetal growth restriction. Small Cited2 null placentas were characterized by disruptions in the JZ, delays in intrauterine trophoblast cell invasion, and compromised plasticity. In the human placentation site, CITED2 was uniquely expressed in the extravillous trophoblast (EVT) cell column and importantly contributed to the development of the EVT cell lineage. We conclude that CITED2 is a conserved regulator of deep hemochorial placentation.

The AKT1-FOXO4 axis reciprocally regulates hemochorial placentation

Hemochorial placentation involves the differentiation of invasive trophoblast cells, specialized cells that possess the capacity to exit the placenta and invade into the uterus where they restructure the vasculature. Invasive trophoblast cells arise from a well-defined compartment within the placenta, referred to as the junctional zone in rat and the extravillous trophoblast cell column in human. In this study, we investigated roles for AKT1, a serine/threonine kinase, in placental development using a genome-edited/loss-of-function rat model. Disruption of AKT1 resulted in placental, fetal and postnatal growth restriction. Forkhead box O4 (Foxo4), which encodes a transcription factor and known AKT substrate, was abundantly expressed in the junctional zone and in invasive trophoblast cells of the rat placentation site. Foxo4 gene disruption using genome editing resulted in placentomegaly, including an enlarged junctional zone. AKT1 and FOXO4 regulate the expression of many of the same transcripts expressed by trophoblast cells, but in opposite directions. In summary, we have identified AKT1 and FOXO4 as part of a regulatory network that reciprocally controls critical indices of hemochorial placenta development.

Infection and disruption of placental multidrug resistance (MDR) transporters: Implications for fetal drug exposure

P-glycoprotein (P-gp, encoded by the ABCB1 gene) and breast cancer resistance protein (BCRP/ABCG2) are efflux multidrug resistance (MDR) transporters localized at the syncytiotrophoblast barrier of the placenta and protect the conceptus from drug and toxin exposure throughout pregnancy. Infection is an important modulator of MDR expression and function. This review comprehensively examines the effect of infection on the MDR transporters, P-gp and BCRP in the placenta. Infection PAMPs such as bacterial lipopolysaccharide (LPS) and viral polyinosinic-polycytidylic acid (poly I:C) and single-stranded (ss)RNA, as well as infection with Zika virus (ZIKV), Plasmodium berghei ANKA (modeling malaria in pregnancy - MiP) and polymicrobial infection of intrauterine tissues (chorioamnionitis) all modulate placental P-gp and BCRP at the levels of mRNA, protein and or function; with specific responses varying according to gestational age, trophoblast type and species (human vs. mice). Furthermore, we describe the expression and localization profile of Toll-like receptor (TLR) proteins of the innate immune system at the maternal-fetal interface, aiming to better understand how infective agents modulate placental MDR. We also highlight important gaps in the field and propose future research directions. We conclude that alterations in placental MDR expression and function induced by infective agents may not only alter the intrauterine biodistribution of important MDR substrates such as drugs, toxins, hormones, cytokines, chemokines and waste metabolites, but also impact normal placentation and adversely affect pregnancy outcome and maternal/neonatal health.

Evidence of Increased Oxidative Stress in the Placental Tissue of Women Who Suffered an Episode of Psychosis during Pregnancy

Psychosis is a complex clinical syndrome resulting in a loss of contact with reality and alterations in behavior and sensorial and motor functions. Although the onset of psychosis can be related to any medical condition, most cases of psychosis are not fully understood. Psychosis may manifest for the first time during pregnancy, which is detrimental to maternofetal well-being. The impact of having a first episode of psychosis during pregnancy on the placenta has not yet been explored. Oxidative stress is thought to take part in the etiopathogenesis of this complex disorder, and this condition can also affect the placenta as it is highly sensitive to changes in the maternal environment. In this sense, the aim of the present work was to study the gene and protein expression through RT-qPCR and immunohistochemistry, respectively, of oxidative stress markers (NOX-1, NOX-2, iNOS, eNOS and PARP) in the placental tissue of women who underwent a first episode of psychosis during pregnancy (FE-PW) in comparison to healthy pregnant women. Our results showed augmented gene and protein expression of NOX-1, NOX-2, iNOS and PARP in the placental tissue of FE-PW. For the first time, we demonstrated that oxidative stress may have an important pathophysiological role in this tissue, aiding in explaining the impact of psychosis on pregnancy and the need for future studies in this field to guide better clinical management of these patients.

The Placental Function Beyond Pregnancy: Insights from Latin America

Currently, more than 100,000 papers had been published studying the placenta in both physiological and pathological contexts. However, relevant health conditions affecting placental function, mostly found in low-income countries, should be evaluated deeper. This review will raise some - of what we think necessary - points of discussion regarding challenging topics not fully understood, including the paternal versus maternal contribution on placental genes imprinting, placenta-brain communication, and some environmental conditions affecting the placenta. The discussions are parts of an international effort to fulfil some gaps observed in this area, and Latin-American research groups currently evaluate that.

Regulators involved in trophoblast syncytialization in the placenta of intrauterine growth restriction

Placental dysfunction refers to the insufficiency of placental perfusion and chronic hypoxia during early pregnancy, which impairs placental function and causes inadequate supply of oxygen and nutrients to the fetus, affecting fetal development and health. Fetal intrauterine growth restriction, one of the most common outcomes of pregnancy-induced hypertensions, can be caused by placental dysfunction, resulting from deficient trophoblast syncytialization, inadequate trophoblast invasion and impaired vascular remodeling. During placental development, cytotrophoblasts fuse to form a multinucleated syncytia barrier, which supplies oxygen and nutrients to meet the metabolic demands for fetal growth. A reduction in the cell fusion index and the number of nuclei in the syncytiotrophoblast are found in the placentas of pregnancies complicated by IUGR, suggesting that the occurrence of IUGR may be related to inadequate trophoblast syncytialization. During the multiple processes of trophoblasts syncytialization, specific proteins and several signaling pathways are involved in coordinating these events and regulating placental function. In addition, epigenetic modifications, cell metabolism, senescence, and autophagy are also involved. Study findings have indicated several abnormally expressed syncytialization-related proteins and signaling pathways in the placentas of pregnancies complicated by IUGR, suggesting that these elements may play a crucial role in the occurrence of IUGR. In this review, we discuss the regulators of trophoblast syncytialization and their abnormal expression in the placentas of pregnancies complicated by IUGR.

The importance of placental lipid metabolism across gestation in obese and non-obese pregnancies

In this commentary, we highlight a new study by Bidne and colleagues that identifies changes in placental lipids and lipid metabolic enzymes that happen not only in the context of parental obesity but also from as early as 4 weeks of gestation. Their assessment of lipid and enzyme content demonstrates a feasible approach to untangling the complexities of metabolic pathologies that impact the lifelong health of both parent and child.

Sex differences in early and term placenta are conserved in adult tissues

BACKGROUND

Pregnancy complications vary based on the fetus's genetic sex, which may, in part, be modulated by the placenta. Furthermore, developmental differences early in life can have lifelong health outcomes. Yet, sex differences in gene expression within the placenta at different timepoints throughout pregnancy and comparisons to adult tissues remains poorly characterized.

METHODS

Here, we collect and characterize sex differences in gene expression in term placentas (≥ 36.6 weeks; 23 male XY and 27 female XX). These are compared with sex differences in previously collected first trimester placenta samples and 42 non-reproductive adult tissues from GTEx.

RESULTS

We identify 268 and 53 sex-differentially expressed genes in the uncomplicated late first trimester and term placentas, respectively. Of the 53 sex-differentially expressed genes observed in the term placentas, 31 are also sex-differentially expressed genes in the late first trimester placentas. Furthermore, sex differences in gene expression in term placentas are highly correlated with sex differences in the late first trimester placentas. We found that sex-differential gene expression in the term placenta is significantly correlated with sex differences in gene expression in 42 non-reproductive adult tissues (correlation coefficient ranged from 0.892 to 0.957), with the highest correlation in brain tissues. Sex differences in gene expression were largely driven by gene expression on the sex chromosomes. We further show that some gametologous genes (genes with functional copies on X and Y) will have different inferred sex differences if the X-linked gene expression in females is compared to the sum of the X-linked and Y-linked gene expression in males.

CONCLUSIONS

We find that sex differences in gene expression are conserved in late first trimester and term placentas and that these sex differences are conserved in adult tissues. We demonstrate that there are sex differences associated with innate immune response in late first trimester placentas but there is no significant difference in gene expression of innate immune genes between sexes in healthy full-term placentas. Finally, sex differences are predominantly driven by expression from sex-linked genes.

Potential Benefits of Anthocyanins in Chronic Disorders of the Central Nervous System

Anthocyanins have been shown to be effective in chronic diseases because of their antioxidant and anti-inflammatory effects together with changes in the gut microbiota and modulation of neuropeptides such as insulin-like growth factor-1. This review will examine whether these mechanisms may be effective to moderate the symptoms of disorders of the central nervous system in humans, including schizophrenia, Parkinson's disease, Alzheimer's disease, autism spectrum disorder, depression, anxiety, attention-deficit hyperactivity disorder and epilepsy. Thus, anthocyanins from fruits and berries should be considered as complementary interventions to improve these chronic disorders.

Effect of third trimester maternal vitamin D levels on placental weight to birth weight ratio in uncomplicated pregnancies

OBJECTIVES

Vitamin D has critical role for the fetal and placental development. Today, placental weight (PW), fetal birth weight (BW), and the PW/BW ratio are used as markers of fetal development. The aim of this study is to evaluate the relationship between vitamin D levels and these markers in uncomplicated pregnancies.

METHODS

This study included 108 women with uncomplicated pregnancies, defined as full-term and healthy pregnancies without perinatal complications. Vitamin D levels <12 ng/mL were classified as deficient, 12-20 ng/mL as insufficient, and >20 ng/mL as normal. Postnatal BW and PW were compared according to maternal serum vitamin D levels.

RESULTS

Maternal age, maternal height, maternal weight, body mass index, nulliparity, gestational age at delivery, mode of delivery, and fetal gender were similar between groups. Postnatal BW, PW, fetal height at birth, and fetal head circumference parameters were similar between the groups. The PW/BW ratio was 21.77±2.20 in the vitamin D deficient group, 21.20±2.40 in the insufficient group, and 19.98±2.37 in the normal group (p=0.012). In addition, there was a significant negative correlation between vitamin D level and the PW/BW ratio (p=0.012, r=0.031).

CONCLUSIONS

Our results indicated that PW/BW ratio which is the marker for prediction adverse perinatal outcomes were significantly increased in the presence of vitamin D deficiency and insufficiency.

Impact of prenatal exposure to Ramadan on disability in Pakistan among adults age 18-64

Purpose

Temporary disruptions to eating and sleeping patterns due to exposure to Ramadan during pregnancy have been shown to increase the probability of disability and chronic health problems later in life. This study aims to analyze the intent-to-treat effect of prenatal exposure to Ramadan (the Islamic month of fasting) on individual disabilities for individuals age 18 to 64 across three provinces encompassing 94% of Pakistan's population.

Subjects and methods

The study uses observational data from 2017 to 2019 by the UN-supported Multiple Indicator Cluster Survey (MICS) on 187,265 adults in Punjab, 71,895 adults in Sindh, and 91,283 in Khyber Pakhtunkhwa, Pakistan. Excluding data on those age > 64 and observations with incomplete data, multivariate regression analysis was conducted on the data of around 277,000 individuals to assess the risk of disability due to pregnancy coinciding with Ramadan.

Results

Considering exposure to Ramadan by calendar month prior to birth, women exposed in particular months have lower rates of disability related to sight (-0.3 percentage point, p < 0.1), memory (-0.3 pp., p < 0.05), and mobility (-0.6 pp., p < 0.05) but a higher chance of hearing problems (0.2 pp., p < 0.1) as compared to women who were not exposed in utero, while men exposed in particular months have a higher likelihood of a disability in sight (0.5 pp., p < 0.05), hearing (0.4 pp., p < 0.05), communication (0.5 pp., p < 0.01), memory (0.5 pp., p < 0.05), or mobility (0.9 pp., p < 0.01) as compared to men who were not exposed to Ramadan and women who were similarly exposed. Considering the provinces separately, the results were dominated by Punjab where overlap of pregnancy with Ramadan increased the likelihood of men experiencing a severe disability in hearing, communication, memory, or mobility. Men in Sindh were more likely to experience a memory or mobility disability, and men in Khyber Pakhtunkhwa were less likely to experience a communication or memory disability.

Conclusions

Pregnant women should be counseled regarding the alterations in eating, nutrition, and sleep patterns that may occur during Ramadan, as exposure to Ramadan during pregnancy increases rates of sight, hearing, memory, communication, and mobility disabilities in men.

Maternal glucocorticoids do not directly mediate the effects of maternal social stress on the fetus

Stress during pregnancy negatively affects the fetus and increases the risk for affective disorders in adulthood. Excess maternal glucocorticoids are thought to mediate fetal programming; however, whether they exert their effects directly or indirectly remains unclear. During pregnancy, protective mechanisms including maternal hypothalamic-pituitary-adrenal (HPA) axis hyporesponsiveness and placental 11β-hydroxysteroid dehydrogenase (11βHSD) type 2, which inactivates glucocorticoids, limit mother-to-fetus glucocorticoid transfer. However, whether repeated stress negatively impacts these mechanisms is not known. Pregnant rats were exposed to repeated social stress on gestational days (GD) 16-20 and several aspects of HPA axis and glucocorticoid regulation, including concentrations of glucocorticoids, gene expression for their receptors (Nr3c1, Nr3c2), receptor chaperones (Fkbp51, Fkbp52) and enzymes that control local glucocorticoid availability (Hsd11b1, Hsd11b2), were investigated in the maternal, placental and fetal compartments on GD20. The maternal HPA axis was activated following stress, though the primary driver was vasopressin, rather than corticotropin-releasing hormone. Despite the stress-induced increase in circulating corticosterone in the dams, only a modest increase was detected in the circulation of female fetuses, with no change in the fetal brain of either sex. Moreover, there was no change in the expression of genes that mediate glucocorticoid actions or modulate local concentrations in the fetal brain. In the placenta labyrinth zone, stress increased Hsd11b2 expression only in males and Fkbp51 expression only in females. Our results indicate that any role glucocorticoids play in fetal programming is likely indirect, perhaps through sex-dependent alterations in placental gene expression, rather than exerting effects via direct crossover into the fetal brain.

Human-Based New Approach Methodologies in Developmental Toxicity Testing: A Step Ahead from the State of the Art with a Feto-Placental Organ-on-Chip Platform

Developmental toxicity testing urgently requires the implementation of human-relevant new approach methodologies (NAMs) that better recapitulate the peculiar nature of human physiology during pregnancy, especially the placenta and the maternal/fetal interface, which represent a key stage for human lifelong health. Fit-for-purpose NAMs for the placental-fetal interface are desirable to improve the biological knowledge of environmental exposure at the molecular level and to reduce the high cost, time and ethical impact of animal studies. This article reviews the state of the art on the available in vitro (placental, fetal and amniotic cell-based systems) and in silico NAMs of human relevance for developmental toxicity testing purposes; in addition, we considered available Adverse Outcome Pathways related to developmental toxicity. The OECD TG 414 for the identification and assessment of deleterious effects of prenatal exposure to chemicals on developing organisms will be discussed to delineate the regulatory context and to better debate what is missing and needed in the context of the Developmental Origins of Health and Disease hypothesis to significantly improve this sector. Starting from this analysis, the development of a novel human feto-placental organ-on-chip platform will be introduced as an innovative future alternative tool for developmental toxicity testing, considering possible implementation and validation strategies to overcome the limitation of the current animal studies and NAMs available in regulatory toxicology and in the biomedical field.

Interactions among maternal smoking, breastfeeding, and offspring genetic factors on the risk of adult-onset hypertension

BACKGROUND

Previous studies have reported that maternal smoking during pregnancy and breastfeeding may affect the occurrence of hypertension, but whether early life factors modify the impact of the offspring's genetic risk on hypertension is still unknown. The aim of this study was to investigate the relationships among maternal smoking and breastfeeding with adult-onset hypertension and the modified impact of offspring genetic susceptibility.

METHODS

This study included 437,185 participants from the UK Biobank who were initially free of hypertension and provided a prospective cohort of individuals aged 40 to 69 years. The association of maternal smoking during pregnancy and breastfeeding with hypertension was examined by using the Cox regression model. Then, a polygenic risk score (PRS) for hypertension was used to test the gene-environmental interaction on hypertension.

RESULTS

During a median follow-up period of 8.7 years, a total of 68,148 cases of hypertension were identified in this study. The hazard ratios (HRs) and 95% confidence intervals (CIs) of hypertension for maternal smoking and breastfeeding were 1.11 (1.09, 1.13) and 0.96 (0.94, 0.98), respectively. However, no evidence of an interaction between maternal smoking and breastfeeding was observed. Across all levels of genetic risk, including high genetic risk, maternal smoking and nonbreastfeeding had higher hypertension hazards than nonmaternal smoking and breastfeeding, respectively. The adjusted HRs (95% CIs) of hypertension were 1.80 (1.73, 1.87) in those who had high genetic predisposition plus maternal smoking and 1.67 (1.60-1.74) in those with nonbreastfeeding and high genetic risk. There were significant additive interactions between maternal smoking or breastfeeding and genetic factors on the incidence of hypertension.

CONCLUSIONS

Maternal smoking and nonbreastfeeding were associated with a higher risk of hypertension in adulthood and may attenuate the risk of hypertension related to genetic factors. These results suggested that adherence to nonmaternal smoking and breastfeeding was associated with a lower risk of hypertension among participants with all gradients of genetic risk.

Unfolding the role of placental-derived Extracellular Vesicles in Pregnancy: From homeostasis to pathophysiology

The human placenta is a critical structure with multiple roles in pregnancy, including fetal nutrition and support, immunological, mechanical and chemical barrier as well as an endocrine activity. Besides, a growing body of evidence highlight the relevance of this organ on the maternofetal wellbeing not only during gestation, but also from birth onwards. Extracellular vesicles (EVs) are complex macromolecular structures of different size and content, acting as carriers of a diverse set of molecules and information from donor to recipient cells. Since its early development, the production and function of placental-derived EVs are essential to ensure an adequate progress of pregnancy. In turn, the fetus receives and produce their own EVs, highlighting the importance of these components in the maternofetal communication. Moreover, several studies have shown the clinical relevance of EVs in different obstetric pathologies such as preeclampsia, infectious diseases or gestational diabetes, among others, suggesting that they could be used as pathophysiological biomarkers of these diseases. Overall, the aim of this article is to present an updated review of the published basic and translational knowledge focusing on the role of placental-derived EVs in normal and pathological pregnancies. We suggest as well future lines of research to take in this novel and promising field.

Paternal epigenetic influences on placental health and their impacts on offspring development and disease

Our efforts to understand the developmental origins of birth defects and disease have primarily focused on maternal exposures and intrauterine stressors. Recently, research into non-genomic mechanisms of inheritance has led to the recognition that epigenetic factors carried in sperm also significantly impact the health of future generations. However, although researchers have described a range of potential epigenetic signals transmitted through sperm, we have yet to obtain a mechanistic understanding of how these paternally-inherited factors influence offspring development and modify life-long health. In this endeavor, the emerging influence of the paternal epigenetic program on placental development, patterning, and function may help explain how a diverse range of male exposures induce comparable intergenerational effects on offspring health. During pregnancy, the placenta serves as the dynamic interface between mother and fetus, regulating nutrient, oxygen, and waste exchange and coordinating fetal growth and maturation. Studies examining intrauterine maternal stressors routinely describe alterations in placental growth, histological organization, and glycogen content, which correlate with well-described influences on infant health and adult onset of disease. Significantly, the emergence of similar phenotypes in models examining preconception male exposures indicates that paternal stressors transmit an epigenetic memory to their offspring that also negatively impacts placental function. Like maternal models, paternally programmed placental dysfunction exerts life-long consequences on offspring health, particularly metabolic function. Here, focusing primarily on rodent models, we review the literature and discuss the influences of preconception male health and exposure history on placental growth and patterning. We emphasize the emergence of common placental phenotypes shared between models examining preconception male and intrauterine stressors but note that the direction of change frequently differs between maternal and paternal exposures. We posit that alterations in placental growth, histological organization, and glycogen content broadly serve as reliable markers of altered paternal developmental programming, predicting the emergence of structural and metabolic defects in the offspring. Finally, we suggest the existence of an unrecognized developmental axis between the male germline and the extraembryonic lineages that may have evolved to enhance fetal adaptation.

Glucose and oxygen in the early intrauterine environment and their role in developmental abnormalities

The early life environment can have profound impacts on the developing conceptus in terms of both growth and morphogenesis. These impacts can manifest in a variety of ways, including congenital fetal anomalies, placental dysfunction with subsequent effects on fetal growth, and adverse perinatal outcomes, or via effects on long-term health outcomes that may not be detected until later childhood or adulthood. Two key examples of environmental influences on early development are explored: maternal hyperglycaemia and gestational hypoxia. These are increasingly common pregnancy exposures worldwide, with potentially profound impacts on population health. We explore what is known regarding the mechanisms by which these environmental exposures can impact early intrauterine development and thus result in adverse outcomes in the immediate, short, and long term.

Human placental development and function

The placenta is a transient fetal organ that plays a critical role in the health and wellbeing of both the fetus and its mother. Functionally, the placenta sustains the growth of the fetus as it facilitates delivery of oxygen and nutrients and removal of waste products. Not surprisingly, defective early placental development is the primary cause of common disorders of pregnancy, including recurrent miscarriage, fetal growth restriction, pre-eclampsia and stillbirth. Adverse pregnancy conditions will also affect the life-long health of the fetus via developmental programming[1]. Despite its critical importance in reproductive success and life-long health, our understanding of placental development is not extensive, largely due to ethical limitations to studying early or chronological placental development, lack of long-term in vitro models, or comparative animal models. In this review, we examine current knowledge of early human placental development, discuss the critical role of the maternal endometrium and of the fetal-maternal dialogue in pregnancy success, and we explore the latest models of trophoblast and endometrial stem cells. In addition, we discuss the role of oxygen in placental formation and function, how nutrient delivery is mediated during the periods of histotrophic nutrition (uptake of uterine secretions) and haemotrophic nutrition (exchange between the maternal and fetal circulations), and how placental endocrine function facilitates fetal growth and development.

Mitochondrial Dysfunction, Mitophagy and Their Correlation with Perinatal Complications: Preeclampsia and Low Birth Weight

Mitochondria are essential organelles and crucial for cellular survival. Mitochondrial biogenesis and mitophagy are dynamic features that are essential for both maintaining the health of the mitochondrial network and cellular demands. The accumulation of damaged mitochondria has been shown to be related to a wide range of pathologies ranging from neurological to musculoskeletal. Mitophagy is the selective autophagy of mitochondria, eliminating dysfunctional mitochondria in cells by engulfment within double-membraned vesicles. Preeclampsia and low birth weight constitute prenatal complications during pregnancy and are leading causes of maternal and fetal mortality and morbidity. Both placental implantation and fetal growth require a large amount of energy, and a defect in the mitochondrial quality control mechanism may be responsible for the pathophysiology of these diseases. In this review, we compiled current studies investigating the role of BNIP3, DRAM1, and FUNDC1, mediators of receptor-mediated mitophagy, in the progression of preeclampsia and the role of mitophagy pathways in the pathophysiology of low birth weight. Recent studies have indicated that mitochondrial dysfunction and accumulation of reactive oxygen species are related to preeclampsia and low birth weight. However, due to the lack of studies in this field, the results are controversial. Therefore, mitophagy-related pathways associated with these pathologies still need to be elucidated. Mitophagy-related pathways are among the promising study targets that can reveal the pathophysiology behind preeclampsia and low birth weight.

Emerging pharmacologic interventions for pre-eclampsia treatment

INTRODUCTION

Pre-eclampsia is a serious pregnancy complication and a major global concern for the mortality of both mother and fetus. Existing symptomatic treatments do not delay disease progression; thus, timely delivery of the baby is the most effective measure. However, the risk of various maternal and fetal injuries remains.

AREAS COVERED

In this review, we summarize the potential strategies for pharmacologic interventions in pre-eclamptic therapy. Specifically, we discuss the pathophysiological process of various effective candidate therapeutics that act on potential pathways and molecular targets to inhibit key stages of the disease. We refer to this pathogenesis-focused drug discovery model as a pathogenesis-target-drug (P-T-D) strategy. Finally, we discuss the introduction of nanotechnologies to improve the safety and efficacy of therapeutics via their specific placental targeting ability and placental retention effects.

EXPERT OPINION

Despite the active development of novel pharmacological treatments based on our current knowledge of pre-eclamptic pathogenesis, investigations are still in the early phase. Thus, further exploration of the pathological mechanisms, integrated with the P-T-D strategy and novel nanosystems, could encourage the development of more effective and safer strategies. Such advances could lead to a shift from expectant management to mechanistic-based therapy for pre-eclampsia.

Patterns in Prenatal Physical Activity and Sedentary Behavior: Associations With Blood Pressure and Placental Features in the MoMHealth Cohort

BACKGROUND

Moderate to vigorous physical activity (MVPA) and sedentary behavior (SED) are associated with blood pressure (BP) and adverse pregnancy outcomes. The authors investigated associations of prenatal MVPA and SED patterns with BP and with placental malperfusion features.

METHODS

Women enrolled in this prospective cohort study in the first trimester. MVPA, SED, and BP were measured objectively each trimester. MVPA and SED trajectories were constructed. Placental examinations were conducted in a subset. Associations of trajectories with BPs were assessed with linear regression adjusted for age, race, education, prepregnancy body mass index, and gestational age. Associations with placental malperfusion lesions and weight were adjusted for key covariates.

RESULTS

One hundred eleven participants were included; placental exams were available in 50. Participants with high (vs low) SED were younger and more likely to have adverse pregnancy outcomes. High SED (vs low) was associated with higher first trimester systolic (β = 5.3; 95% confidence interval, 0.0 to 10.6) and diastolic (β = 5.0; 95% confidence interval, 1.4 to 8.6) and higher second trimester diastolic (β = 4.9; 95% confidence interval, 1.6 to 8.2) BP. Medium and high MVPA groups were associated with lower postpartum diastolic BP. Trajectories were not associated with placental malperfusion.

CONCLUSIONS

MVPA and SED patterns were differentially associated with prenatal and postpartum BP. Encouraging favorable levels of both might help women achieve lower BP during and after pregnancy.