Identifying target sites for placental therapeutics through the comparison of normal term pregnancies and intrauterine growth restricted proteomes

A variety of pathologies, including intrauterine growth restriction (IUGR), have been linked to placental insufficiencies as important causal factors, however, little has been done to develop therapeutics that may improve placental development, structure and function. The placenta offers the opportunity to manipulate the in-utero environment without directly intervening with the fetus, accessible from the maternal circulation, a vital but temporary organ, the placenta is no longer required after birth. Developing therapeutics must involve multiple aspects of targeting and safety to ensure no off-target impact on the pregnant person or fetus as well as enhance efficiency of delivery. In addition to our studies on nanoparticle delivery to the placenta [1] we are developing targeting strategies to allow peripheral delivery via the maternal circulation. In this study we have performed the isolation of the microvillous membrane from human placental syncytiotrophoblast (the targeting cell) and via proteomic analysis identified potential targeting moieties, we have then compared this to publicly available data from pregnancies complicated by fetal growth restriction to ensure that we do not identify targets which would be reduced in FGR, resulting in less efficient targeting.

Epigenetic: New Insight in Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is the more frequent metabolic complication of pregnancy with a prevalence that is significantly increased in the last decade accounting for 12–18% of all pregnancies. Recent evidences strongly suggests that epigenetic profile changes could be involved in the onset of GDM and its related maternal and fetal complications. In particular, the unfavorable intrauterine environment related to hyperglycemia, a feature of GDM, has been evidenced to exert a negative impact on the establishment of the epigenome of the offspring. Furthermore the adverse in utero environment could be one of the mechanisms engaged in the development of adult chronic diseases. The purpose of this article is to review a number of published studies to fill the gap in our understanding of how maternal lifestyle and intrauterine environment influence molecular modifications in the offspring, with an emphasis on epigenetic alterations.

The Isolated in Utero Environment Is Conducive to the Emergence of RNA and DNA Virus Variants

The host’s immune status may affect virus evolution. Little is known about how developing fetal and placental immune milieus affect virus heterogeneity. This knowledge will help us better understand intra-host virus evolution and how new virus variants emerge. The goal of our study was to find out whether the isolated in utero environment—an environment with specialized placental immunity and developing fetal immunity—supports the emergence of RNA and DNA virus variants. We used well-established porcine models for isolated Zika virus (RNA virus) and porcine circovirus 2 (DNA virus) fetal infections. We found that the isolated in utero environment was conducive to the emergence of RNA and DNA virus variants. Next-generation sequencing of nearly whole virus genomes and validated bioinformatics pipelines identified both unique and convergent single nucleotide variations in virus genomes isolated from different fetuses. Zika virus and PCV2 in utero evolution also resulted in single nucleotide variations previously reported in the human and porcine field samples. These findings should encourage further studies on virus evolution in placenta and fetuses, to better understand how virus variants emerge and how in utero viral evolution affects congenital virus transmission and pathogenicity.

Placental Villous Explant Culture 2.0: Flow Culture Allows Studies Closer to the In Vivo Situation

During pregnancy, freely floating placental villi are adapted to fluid shear stress due to placental perfusion with maternal plasma and blood. In vitro culture of placental villous explants is widely performed under static conditions, hoping the conditions may represent the in utero environment. However, static placental villous explant culture dramatically differs from the in vivo situation. Thus, we established a flow culture system for placental villous explants and compared commonly used static cultured tissue to flow cultured tissue using transmission and scanning electron microscopy, immunohistochemistry, and lactate dehydrogenase (LDH) and human chorionic gonadotropin (hCG) measurements. The data revealed a better structural and biochemical integrity of flow cultured tissue compared to static cultured tissue. Thus, this new flow system can be used to simulate the blood flow from the mother to the placenta and back in the most native-like in vitro system so far and thus can enable novel study designs.

Collaboration to Improve Neuroprotection and Neuropromotion in the NICU: Team Education and Family Engagement

The number of babies born extremely low birth weight surviving to be discharged home after experiencing the NICU continues to improve. Unfortunately, early sensory development for these babies occurs in an environment vastly different from the intended in-utero environment and places them at high risk of long-term neurodevelopmental and neurocognitive challenges. Our goal in the NICU must transition from simply discharge home to supporting the neurosensory development necessary for a thriving lifetime. To accomplish a goal of thriving families and thriving babies, it is clear the NICU interprofessional team must share an understanding of neurosensory development, the neuroprotective strategies safeguarding development, the neuropromotive strategies supporting intended maturational development, and the essential nature of family integration in these processes. We share the educational endeavors of 11 center collaboratives in establishing the foundational knowledge necessary to support preterm babies and their families.

Let’s Talk about Placental Sex, Baby: Understanding Mechanisms That Drive Female- and Male-Specific Fetal Growth and Developmental Outcomes

It is well understood that sex differences exist between females and males even before they are born. These sex-dependent differences may contribute to altered growth and developmental outcomes for the fetus. Based on our initial observations in the human placenta, we hypothesised that the male prioritises growth pathways in order to maximise growth through to adulthood, thereby ensuring the greatest chance of reproductive success. However, this male-specific “evolutionary advantage” likely contributes to males being less adaptable to shifts in the in-utero environment, which then places them at a greater risk for intrauterine morbidities or mortality. Comparatively, females are more adaptable to changes in the in-utero environment at the cost of growth, which may reduce their risk of poor perinatal outcomes. The mechanisms that drive these sex-specific adaptations to a change in the in-utero environment remain unclear, but an increasing body of evidence within the field of developmental biology would suggest that alterations to placental function, as well as the feto-placental hormonal milieu, is an important contributing factor. Herein, we have addressed the current knowledge regarding sex-specific intrauterine growth differences and have examined how certain pregnancy complications may alter these female- and male-specific adaptations.

The Epiallelic Nature of Mouse rDNA

Ribosomal DNA (rDNA) displays substantial inter-individual genetic variation in human and mouse. Here we report that 45S rDNA units in the C57BL/6J mouse strain are epiallelic, existing as distinct genetic haplotypes that influence the epigenetic state and transcriptional output of any given unit. Epigenetic dynamics at these haplotypes are dichotomous and lifestage specific: at one haplotype, the DNA methylation state is sensitive to the in utero environment, but refractory to post-weaning influences, whereas other haplotypes entropically gain DNA methylation during ageing only. rDNA epiallelism is influenced by total rDNA copy number, and also found in other inbred mouse strains and humans. In the future, it will be important to consider the impact of inter-individual rDNA (epi)genetic variation on mammalian phenotypes and diseases.

Endometrium on-a-chip reveals insulin- and glucose-induced alterations in the transcriptome and proteomic secretome

The molecular interactions between the maternal environment and the developing embryo that are key for early pregnancy success and are influenced by factors such as maternal metabolic status. Our understanding of the mechanism(s) through which these individual nutritional stressors alter endometrial function and the in utero environment for early pregnancy success is, however, limited. Here we report, for the first time, the use of an endometrium-on-a-chip microfluidics approach to produce a multi-cellular endometrium in vitro. Isolated endometrial cells (epithelial and stromal) from the uteri of non-pregnant cows in the early-luteal phase (Day 4-7), were seeded in the upper chamber of the device (epithelial cells; 4-6 10 4 cells/mL) and stromal cells seeded in the lower chamber (1.5-2 10 4 cells/mL). Exposure of cells to different concentrations of glucose (0.5, 5.0 or 50 mM) or insulin (Vehicle, 1 or 10 ng/mL) were performed at a flow rate of 1µL/min for 72 hr. Quantitative differences in the cellular transcriptome and the secreted proteome of in vitro-derived uterine luminal fluid (ULF) were determined by RNA-sequencing and Tandem Mass Tagging Mass Spectrometry (TMT-MS), respectively. High glucose concentrations altered 21 and 191 protein-coding genes in epithelial and stromal cells, respectively (p<0.05), with a dose-dependent quantitative change in the protein secretome (1 and 23 proteins). Altering insulin concentrations resulted in limited transcriptional changes including transcripts for insulin-like binding proteins that were cell specific but altered the quantitative secretion of 196 proteins. These findings highlight one potential mechanism by which changes to maternal glucose and insulin alter uterine function.

Maternal Metabolome in Pregnancy and Childhood Asthma or Recurrent Wheeze in the Vitamin D Antenatal Asthma Reduction Trial

The in utero environment during pregnancy has important implications for the developing health of the child. We aim to examine the potential impact of maternal metabolome at two different timepoints in pregnancy on offspring respiratory health in early life. In 685 mother-child pairs from the Vitamin D Antenatal Asthma Reduction Trial, we assessed the prospective associations between maternal metabolites at both baseline (10–18 weeks gestation) and third trimester (32–38 weeks gestation) and the risk of child asthma or recurrent wheeze by age three using logistic regression models accounting for confounding factors. Subgroup analyses were performed by child sex. Among 632 metabolites, 19 (3.0%) and 62 (9.8%) from baseline and third trimester, respectively, were associated with the outcome (p-value < 0.05). Coffee-related metabolites in the maternal metabolome appeared to be of particular importance. Caffeine, theophylline, trigonelline, quinate, and 3-hydroxypyridine sulfate were inversely associated with asthma risk at a minimum of one timepoint. Additional observations also highlight the roles of steroid and sphingolipid metabolites. Overall, there was a stronger relationship between the metabolome in later pregnancy and offspring asthma risk. Our results suggest that alterations in prenatal metabolites may act as drivers of the development of offspring asthma.

Gestational diabetes mellitus in pregnancy increased erythropoietin level affecting differentiation potency of haematopoietic stem cell of umbilical cord blood

Background The in utero environment has many factors that can support cell differentiation. Cytokines, chemokines and growth factors play big roles in haematopoietic mechanisms. Some diseases like gestational diabetes mellitus (GDM) might affect the environment and haematopoietic stem cell (HSC) quality. The aim of this study is to investigate the adverse effects of GDM on umbilical cord blood (UCB) HSC in terms of differentiation potency including the UCB parameters used for banking and transplantation purposes. Methods UCB-HSC was isolated and further enriched using immuno-magnetic separation beads (MACS). The UCB-HSC were cultured in methylcellulose media to investigate the differentiation potency. The level of erythropoietin (EPO) and insulin in the UCB plasma was measured using enzyme linked immunoassay (ELISA) technique. Results The UCB parameters; volume, total nucleated count (TNC) and total CD34+ cells were significantly reduced in the GDM group compared to the control group. The number of HSC progenitors’ colonies were significantly reduced in the GDM group except for progenitor BFU-E, which was significantly increased (GDM=94.19 ± 6.21, Control=73.61 ± 2.73, p=0.010 ). This data was associated with higher EPO level in GDM group. However, the insulin level in the GDM group was comparable to the Control group. Conclusion Our results suggest that the changes in the in utero environment due to abnormalities during pregnancy such as GDM affect the differentiation potency of UCB-HSC. These findings can be considered as an additional parameter for the inclusion and exclusion criteria for UCB banking, particularly for mothers with GDM.