The Role of Placental Hormones in Mediating Maternal Adaptations to Support Pregnancy and Lactation

The trophoblast surface becomes refractory to adhesion by congenitally transmitted Toxoplasma gondii and Listeria monocytogenes during cytotrophoblast to syncytiotrophoblast development

The placenta is a critical barrier against viral, bacterial, and eukaryotic pathogens. For most teratogenic pathogens, the precise molecular mechanisms of placental resistance are still being unraveled. Given the importance of understanding these mechanisms and challenges in replicating trophoblast-pathogen interactions using in vitro models, we tested an existing stem-cell-derived model of trophoblast development for its relevance to infection with Toxoplasma gondii. We grew human trophoblast stem cells (TSCT) under conditions leading to either syncytiotrophoblast (TSSYN) or cytotrophoblast (TSCYT) and infected them with T. gondii. We evaluated T. gondii proliferation and invasion, cell ultrastructure, as well as for transcriptome changes after infection. TSSYNs cells showed similar ultrastructure compared to primary cells and villous explants when analyzed by transmission electron microscopy and scanning electron microscopy (SEM), a resistance to T. gondii adhesion could be visualized on the SEM level. Furthermore, TSSYNs were highly refractory to parasite adhesion and replication, while TSCYTs were not. RNA-seq data on mock-treated and infected cells identified differences between cell types as well as how they responded to T. gondii infection. We also evaluated if TSSC-derived SYNs and CYTs had distinct resistance profiles to another vertically transmitted facultative intracellular pathogen, Listeria monocytogenes. We demonstrate that TSSYNs are highly resistant to L. monocytogenes, while TSCYTs are not. Like T. gondii, TSSYN resistance to L. monocytogenes was at the level of bacterial adhesion. Altogether, our data indicate that stem-cell-derived trophoblasts recapitulate resistance profiles of primary cells to T. gondii and highlight the critical importance of the placental surface in cell-autonomous resistance to teratogens.IMPORTANCECongenital toxoplasmosis can cause a devastating consequence to the fetus. To reach the fetus's tissues, Toxoplasma gondii must cross the placenta barrier. However, how this parasite crosses the placenta and the precise molecular mechanisms of placental resistance to this parasite are still unknown. In this study, we aimed to characterize a new cellular model of human trophoblast stem cells to determine their resistance, susceptibility, and response to T. gondii. Syncytiotrophoblast derived from trophoblast stem cells recapitulate the resistance profile similarly to placenta cells. We also showed that these cells are highly resistant to Listeria monocytogenes, at the level of bacterial adhesion. Our results suggest that resisting pathogen adhesion/attachment may be a generalized mechanism of syncytiotrophoblast resistance, and trophoblast stem cells represent a promising model to investigate cell-intrinsic mechanisms of resistance to pathogen adhesion and replication.

Immunometabolic adaptation in monocytes underpins functional changes during pregnancy

Metabolic heterogeneity is a determinant of immune cell function. The normal physiological metabolic reprogramming of pregnancy that ensures the fuel requirements of mother and baby are met, might also underpin changes in immunity that occur with pregnancy and manifest as altered responses to pathogens and changes to autoimmune disease symptoms. Using peripheral blood from pregnant women at term, we reveal that monocytes lose M2-like and gain M1-like properties accompanied by reductions in mitochondrial mass, maximal respiration, and cardiolipin content in pregnancy; glycolysis is unperturbed. We establish that muramyl dipeptide (MDP)-stimulated cytokine production relies on oxidative metabolism, then show in pregnancy reduced cytokine production in response to MDP but not LPS. Overall, mitochondrially centered metabolic capabilities of late gestation monocytes are down-regulated revealing natural plasticity in monocyte phenotype and function that could reveal targets for improving pregnancy outcomes but also yield alternative therapeutic approaches to diverse metabolic and/or immune-mediated diseases beyond pregnancy.

Neurodevelopment and Metabolism in the Maternal-Placental-Fetal Unit

Importance

Disturbances in maternal, placental, and fetal metabolism are associated with developmental outcomes. Associations of maternal, placental, and fetal metabolism with subsequent neurodevelopmental outcomes in the child are understudied.

Objective

To investigate the metabolic associations within the maternal-placental-fetal unit and subsequent neurodevelopmental outcomes in younger siblings of children with autism spectrum disorder (ASD).

Design, Setting, and Participants

This cohort study was conducted within a subset of the Markers of Autism Risk in Babies, Learning Early Signs (MARBLES) cohort. MARBLES is a prospective birth cohort of younger siblings of children with ASD assessed for neurodevelopmental outcomes at approximately age 36 months. Participants in MARBLES were recruited through the UC Davis MIND Institute. This subset of the MARBLES cohort included younger siblings born between 2009 and 2015. Maternal third trimester serum, placental tissue, and umbilical cord serum samples were collected from participants. Only pregnancies with at least 2 of these sample types were included in this analysis. Data analysis was conducted from March 1, 2023, to March 15, 2024.

Exposures

Quantitative metabolomics analysis was conducted on maternal third trimester serum, as well as placental tissue and umbilical cord serum collected at delivery.

Main Outcomes and Measures

Using the Autism Diagnostic Observation Schedule and Mullen Scales of Early Learning, outcomes were classified as ASD, other nontypical development (non-TD), and typical development (TD).

Results

This analysis included 100 maternal serum samples, 141 placental samples, and 124 umbilical cord serum samples from 152 pregnancies (median [IQR] maternal age, 34.6 [30.8-38.3] years; median [IQR] gestational age, 39.0 [38.6-39.7] weeks; 87 [57.2%] male infants). There was no evidence that the maternal third trimester serum metabolome was significantly associated with the other metabolomes. The placental and cord serum metabolomes were highly correlated (first latent variate pair: R2 = 0.75; P < .001) and the variate scores for each tissue were significantly associated with reduced risk of non-TD (placenta: relative risk [RR], 0.13; 95% CI, 0.02-0.71; cord: RR, 0.13; 95% CI, 0.03-0.70) but not ASD (placenta: RR, 1.09; 95% CI, 0.42-2.81; cord: RR, 0.63; 95% CI, 0.23-1.73) compared with the TD reference group.

Conclusions and Relevance

In this cohort study of children with high familial risk of ASD, placental and cord serum metabolism at delivery were highly correlated. Furthermore, placental and cord serum metabolic profiles were associated with risk of non-TD.

Defective Visceral Adipose Tissue Adaptation in Gestational Diabetes Mellitus

CONTEXT

Gestational diabetes mellitus (GDM) is a complex obstetric condition affecting localized glucose metabolism, resulting in systemic metabolic dysfunction.

OBJECTIVE

This cross-sectional study aimed to explore visceral adipose tissue (VAT) as an integral contributor to GDM, focusing on elucidating the specific contribution of obesity and GDM pathology to maternal outcomes.

METHODS

Fifty-six nulliparous pregnant women were recruited, including normal glucose tolerant (NGT) (n = 30) and GDM (n = 26) participants. Participants were subgrouped as nonobese (BMI <30 kg/m2) or obese (BMI ≥30 kg/m2). Metabolic markers in circulation, VAT, and placenta were determined. Morphological analysis of VAT and immunoblotting of the insulin signaling cascade were performed.

RESULTS

GDM participants demonstrated hyperinsulinemia and elevated homeostatic model assessment for insulin resistance (HOMA-IR) scores relative to NGT participants. The GDM-obese subgroup had significant VAT adipocyte hypoplasia relative to NGT-nonobese tissue. GDM-obese VAT had significantly lower insulin receptor substrate (IRS)-2 expression, with elevated ser312 phosphorylation of IRS-1, relative to NGT-nonobese. GDM-obese participants had significantly elevated circulating leptin levels and placental adipsin secretion, while GDM-nonobese participants had elevated circulating adipsin levels with reduced placental adiponectin secretion.

CONCLUSION

These findings suggest that GDM-obese pregnancy is specifically characterized by inadequate VAT remodeling and dysfunctional molecular signaling, which contribute to insulin resistance and hinder metabolic health.

Placenta: an old organ with new functions

The transition from oviparity to viviparity and the establishment of feto-maternal communications introduced the placenta as the major anatomical site to provide nutrients, gases, and hormones to the developing fetus. The placenta has endocrine functions, orchestrates maternal adaptations to pregnancy at different periods of pregnancy, and acts as a selective barrier to minimize exposure of developing fetus to xenobiotics, pathogens, and parasites. Despite the fact that this ancient organ is central for establishment of a normal pregnancy in eutherians, the placenta remains one of the least studied organs. The first step of pregnancy, embryo implantation, is finely regulated by the trophoectoderm, the precursor of all trophoblast cells. There is a bidirectional communication between placenta and endometrium leading to decidualization, a critical step for maintenance of pregnancy. There are three-direction interactions between the placenta, maternal immune cells, and the endometrium for adaptation of endometrial immune system to the allogeneic fetus. While 65% of all systemically expressed human proteins have been found in the placenta tissues, it expresses numerous placenta-specific proteins, whose expression are dramatically changed in gestational diseases and could serve as biomarkers for early detection of gestational diseases. Surprisingly, placentation and carcinogenesis exhibit numerous shared features in metabolism and cell behavior, proteins and molecular signatures, signaling pathways, and tissue microenvironment, which proposes the concept of "cancer as ectopic trophoblastic cells". By extensive researches in this novel field, a handful of cancer biomarkers has been discovered. This review paper, which has been inspired in part by our extensive experiences during the past couple of years, highlights new aspects of placental functions with emphasis on its immunomodulatory role in establishment of a successful pregnancy and on a potential link between placentation and carcinogenesis.

Evidence that highly canalized fetal traits are sensitive to intergenerational effects of maternal developmental nutrition

OBJECTIVES

Maternal experiences before pregnancy predict birth outcomes, a key indicator of health trajectories, but the timing and pathways for these effects are poorly understood. Here we test the hypothesis that maternal pre-adult growth patterns predict pregnancy glucose and offspring fetal growth in Cebu, Philippines.

METHODS

Using multiple regression and path analysis, gestational age-adjusted birthweight and variables reflecting infancy, childhood, and post-childhood/adolescent weight gain (conditional weights) were used to predict pregnancy HbA1c and offspring birth outcomes among participants in the Cebu Longitudinal Health and Nutrition Survey.

RESULTS

Maternal early/mid-childhood weight gain predicted birth weight, length, and head circumference in female offspring. Late-childhood/adolescent weight gain predicted birth length, birth weight, skinfold thickness, and head circumference in female offspring, and head circumference in male offspring. Pregnancy HbA1c did not mediate relationships between maternal growth and birth size parameters.

DISCUSSION

In Cebu, maternal growth patterns throughout infancy, childhood, and adolescence predict fetal growth via a pathway independent of circulating glucose, with stronger impacts on female than male offspring, consistent with a role of developmental nutrition on offspring fetal growth. Notably, the strength of relationships followed a pattern opposite to what occurs in response to acute pregnancy stress, with strongest effects on head circumference and birth length and weakest on skinfolds. We speculate that developmental sensitivities are reversed for stable, long-term nutritional cues that reflect average local environments. These findings are relevant to public health and life-history theory as further evidence of developmental influences on health and resource allocation across the life course.

Progesterone increases hepatic lipid content and plasma lipid levels through PR- B-mediated lipogenesis

Progesterone (P4) is a crucial reproductive hormone that acts as a precursor for all other endogenous steroids. P4 modulates transcriptional activity during reproduction by binding to progesterone receptors (PR). However, the physiological role of P4 in the liver is understudied. P4-mediated lipid metabolism in the liver was investigated in this study, as P4 facilitates insulin resistance and influences energy metabolism. While exogenous lipids are mainly obtained from food, the liver synthesizes endogenous triglycerides and cholesterol from a carbohydrate diet. Hepatic de novo lipogenesis (DNL) is primarily determined by acetyl-CoA and its biosynthetic pathways, which involve fatty acid and cholesterol synthesis. While P4 increased the hepatic levels of sterol regulatory element-binding protein 1 C (SREBP-1 C), peroxisome proliferator-activated receptor-gamma (PPARγ), acetyl-CoA carboxylase (ACC), and CD36, co-treatment with the P4 receptor antagonist RU486 blocked these proteins and P4-mediated lipogenesis. RNA sequencing was used to assess the role of P4 in lipogenic events, such as fatty liver and fatty acid metabolism, lipoprotein signaling, and cholesterol metabolism. P4 induced hepatic DNL and lipid anabolism were confirmed in the liver of ovarian resection mice fed a high-fat diet or in pregnant mice. P4 increased lipogenesis directly in mice exposed to P4 and indirectly in fetuses exposed to maternal P4. The lipid balance between lipogenesis and lipolysis determines fat build-up and is linked to lipid metabolism dysfunction, which involves the breakdown and storage of fats for energy and the synthesis of structural and functional lipids. Therefore, P4 may impact the lipid metabolism and reproductive development during gestation.

Modeling Normal Mouse Uterine Contraction and Placental Perfusion with Non-invasive Longitudinal Dynamic Contrast Enhancement MRI

The placenta is a transient organ critical for fetal development. Disruptions of normal placental functions can impact health throughout an individual's entire life. Although being recognized by the NIH Human Placenta Project as an important organ, the placenta remains understudied, partly because of a lack of non-invasive tools for longitudinally evaluation for key aspects of placental functionalities. Non-invasive imaging that can longitudinally probe murine placental health in vivo are critical to understanding placental development throughout pregnancy. We developed advanced imaging processing schemes to establish functional biomarkers for non-invasive longitudinal evaluation of placental development. We developed a dynamic contrast enhancement magnetic resonance imaging (DCE-MRI) pipeline combined with advanced image process methods to model uterine contraction and placental perfusion dynamics. Our novel imaging pipeline uses subcutaneous administration of gadolinium for steepest-slope based perfusion evaluation. This enables non-invasive longitudinal monitoring. Additionally, we advance the placental perfusion chamber paradigm with a novel physiologically-based threshold model for chamber localization and demonstrate spatially varying placental chambers using multiple functional metrics that assess mouse placental development and continuing remodeling throughout gestation. Lastly, using optic flow to quantify placental motions arisen from uterine contractions in conjunction with time-frequency analysis, we demonstrated that the placenta exhibited asymmetric contractile motion.

Maternal fasting serum C-peptide concentrations in the first and second trimesters and subsequent risk of gestational diabetes mellitus: A nested case-control study among Chinese women

OBJECTIVE

To examine the association of serum connecting peptide (C-peptide) concentrations with gestational diabetes mellitus (GDM) risk among Chinese women.

METHODS

A nested case-control study was conducted on 436 reproductive-aged women, involving 218 GDM cases and 218 controls matched at 1:1 by maternal age, in Beijing, China between January 2016 and December 2017. Fasting serum C-peptide were successively determined at 10-14 and 15-20 weeks of gestation. Restricted cubic spline and logistic regression analyses were utilized, and receiver operating characteristic (ROC) curves were generated to evaluate the predictive capacity of C-peptide for GDM.

RESULTS

Fasting serum C-peptide concentrations exhibited a significant decrease from the initial to the subsequent trimester in females with normal glucose tolerance (NGT). For each 1 log ng/mL increase of fasting serum C-peptide during the first and second trimesters, GDM risk increased by 2.38-fold [odds ratio (OR): 2.38, 95% confidence intervals (95%CI): 1.33-4.40] and 3.07-fold (OR: 3.07, 95%CI: 1.49-6.62), respectively. The areas under the ROC curves for the first- and second-trimester C-peptide were 80.4% and 82.4%.

CONCLUSION

Our findings revealed a positive correlation between fasting serum C-peptide during the first and second trimesters and the risk of GDM or its subtypes, underscoring the potential of C-peptide as a predictor for GDM development.

Preconception maternal retinal arteriolar narrowing and fetal growth throughout pregnancy: A prospective cohort study

OBJECTIVE

To investigate the association between preconception maternal retinal arteriolar calibre and fetal growth.

DESIGN, SETTING AND POPULATION

A hospital-based, prospective preconception cohort including 369 women with a singleton live birth.

METHODS

We collected detailed information on sociodemographic status, pregnancy history and lifestyle, and performed retinal imaging at the preconception visit.

MAIN OUTCOME MEASURES

We retrieved medical records documenting fetal growth biometrics (e.g., abdominal circumference [AC], head circumference [HC], femur length [FL]) at 11-13, 18-21, 24-28, and 32-34 weeks throughout pregnancy. We then computed the z scores for all fetal growth biometrics from 14 weeks of gestation where data were available, referencing the INTERGROWTH-21st fetal growth chart. We used a linear mixed model to estimate the association between maternal preconception retinal arteriolar calibre and fetal growth biometrics z scores throughout pregnancy, with random intercept accounting for repeated measures within individuals. We then performed a multivariable linear regression of maternal preconception retinal arteriolar calibre and z score changes for all fetal growth biometrics between 24-28 weeks and 32-34 weeks of gestation, after full adjustment.

RESULTS

Maternal preconception generalised retinal arteriolar narrowing was consistently associated with a reduction in fetal AC z scores (-0.34; 95% CI -0.66 to -0.03) throughout pregnancy. In addition, women with preconception generalised retinal arteriolar narrowing tended to have significantly reduced z score changes in AC (-0.41; 95% CI -0.90 to -0.001) and fetal FL (-0.55; 95% CI -1.00 to -0.10) between 24-28 weeks and 32-34 weeks of gestation, respectively.

CONCLUSIONS

Our findings suggest that women with narrower preconception retinal arterioles had smaller fetuses, evidenced by reductions in AC and FL z score throughout pregnancy.

The science of uncertainty guides fetal-neonatal neurology principles and practice: diagnostic-prognostic opportunities and challenges

Fetal-neonatal neurologists (FNNs) consider diagnostic, therapeutic, and prognostic decisions strengthened by interdisciplinary collaborations. Bio-social perspectives of the woman's health influence evaluations of maternal-placental-fetal (MPF) triad, neonate, and child. A dual cognitive process integrates "fast thinking-slow thinking" to reach shared decisions that minimize bias and maintain trust. Assessing the science of uncertainty with uncertainties in science improves diagnostic choices across the developmental-aging continuum. Three case vignettes highlight challenges that illustrate this approach. The first maternal-fetal dyad involved a woman who had been recommended to terminate her pregnancy based on an incorrect diagnosis of an encephalocele. A meningocele was subsequently identified when she sought a second opinion with normal outcome for her child. The second vignette involved two pregnancies during which fetal cardiac rhabdomyoma was identified, suggesting tuberous sclerosis complex (TSC). One woman sought an out-of-state termination without confirmation using fetal brain MRI or postmortem examination. The second woman requested pregnancy care with postnatal evaluations. Her adult child experiences challenges associated with TSC sequelae. The third vignette involved a prenatal diagnosis of an open neural tube defect with arthrogryposis multiplex congenita. The family requested prenatal surgical closure of the defect at another institution at their personal expense despite receiving a grave prognosis. The subsequent Management of Myelomeningocele Study (MOMS) would not have recommended this procedure. Their adult child requires medical care for global developmental delay, intractable epilepsy, and autism. These three evaluations involved uncertainties requiring shared clinical decisions among all stakeholders. Falsely negative or misleading positive interpretation of results reduced chances for optimal outcomes. FNN diagnostic skills require an understanding of dynamic gene-environment interactions affecting reproductive followed by pregnancy exposomes that influence the MPF triad health with fetal neuroplasticity consequences. Toxic stressor interplay can impair the neural exposome, expressed as anomalous and/or destructive fetal brain lesions. Functional improvements or permanent sequelae may be expressed across the lifespan. Equitable and compassionate healthcare for women and families require shared decisions that preserve pregnancy health, guided by person-specific racial-ethnic, religious, and bio-social perspectives. Applying developmental origins theory to neurologic principles and practice supports a brain health capital strategy for all persons across each generation.

Specific expression and blood kinetics for relaxin 2, lipocalin 2, and tissue factor pathway inhibitor 2 at the canine placenta and pregnant bloods

In general, humoral factors released from the placenta influence pregnancy progression, but the involvement of the canine placenta is often unidentified. We investigated specific genes in canine placentas and analyzed the blood dynamics of the translated proteins. Furthermore, RNAs are known to be released from placentas embedding in exosomes, a type of extracellular vesicles. Here, the presence of cell-free RNAs in pregnant serums was also confirmed. RNA specimens were purified from the normal healthy dog placentas and applied to RNA-Seq analysis. Expressions of frequent genes were confirmed by RT-PCR using placentas from other individuals and breeds. Relaxin (RLN) 2, lipocalin (LCN) 2, and tissue factor pathway inhibitor (TFPI) 2 were selected as high-expressed and placenta-specific genes. By western blot, the three factors were clearly detected in the pregnant serums. Quantitative analysis revealed that the amount of RLN2 increased significantly from non-pregnancy to day 41 of pregnancy. Regarding LCN2 and TFPI2, the protein serum levels elevated during pregnancy, but the statistical differences were not detected. Exosomes were found in all pregnant serums; however, the percentage was less than 6% in total extracellular vesicles. The cell-free RNA related to RLN2 was detected, but no elevation was confirmed during pregnancy. We found specific genes in the canine placenta and the transition of their translated protein into the blood. These factors may become useful tools for research on canine pregnancy and monitoring of reproductive management. Exosomes and cell-free RNA could not be found to be valid in canine reproduction.

Interdisciplinary fetal-neonatal neurology training applies neural exposome perspectives to neurology principles and practice

An interdisciplinary fetal-neonatal neurology (FNN) program over the first 1,000 days teaches perspectives of the neural exposome that are applicable across the life span. This curriculum strengthens neonatal neurocritical care, pediatric, and adult neurology training objectives. Teaching at maternal-pediatric hospital centers optimally merges reproductive, pregnancy, and pediatric approaches to healthcare. Phenotype-genotype expressions of health or disease pathways represent a dynamic neural exposome over developmental time. The science of uncertainty applied to FNN training re-enforces the importance of shared clinical decisions that minimize bias and reduce cognitive errors. Trainees select mentoring committee participants that will maximize their learning experiences. Standardized questions and oral presentations monitor educational progress. Master or doctoral defense preparation and competitive research funding can be goals for specific individuals. FNN principles applied to practice offer an understanding of gene-environment interactions that recognizes the effects of reproductive health on the maternal-placental-fetal triad, neonate, child, and adult. Pre-conception and prenatal adversities potentially diminish life-course brain health. Endogenous and exogenous toxic stressor interplay (TSI) alters the neural exposome through maladaptive developmental neuroplasticity. Developmental disorders and epilepsy are primarily expressed during the first 1,000 days. Communicable and noncommunicable illnesses continue to interact with the neural exposome to express diverse neurologic disorders across the lifespan, particularly during the critical/sensitive time periods of adolescence and reproductive senescence. Anomalous or destructive fetal neuropathologic lesions change clinical expressions across this developmental-aging continuum. An integrated understanding of reproductive, pregnancy, placental, neonatal, childhood, and adult exposome effects offers a life-course perspective of the neural exposome. Exosome research promises improved disease monitoring and drug delivery starting during pregnancy. Developmental origins of health and disease principles applied to FNN practice anticipate neurologic diagnoses with interventions that can benefit successive generations. Addressing health care disparities in the Global South and high-income country medical deserts require constructive dialogue among stakeholders to achieve medical equity. Population health policies require a brain capital strategy that reduces the global burden of neurologic diseases by applying FNN principles and practice. This integrative neurologic care approach will prolong survival with an improved quality of life for persons across the lifespan confronted with neurological disorders.

Recent progress in metabolic reprogramming in gestational diabetes mellitus: a review

Gestational diabetes mellitus is a prevalent metabolic disease that can impact the normal course of pregnancy and delivery, leading to adverse outcomes for both mother and child. Its pathogenesis is complex and involves various factors, such as insulin resistance and β-cell dysfunction. Metabolic reprogramming, which involves mitochondrial oxidative phosphorylation and glycolysis, is crucial for maintaining human metabolic balance and is involved in the pathogenesis and progression of gestational diabetes mellitus. However, research on the link and metabolic pathways between metabolic reprogramming and gestational diabetes mellitus is limited. Therefore, we reviewed the relationship between metabolic reprogramming and gestational diabetes mellitus to provide new therapeutic strategies for maternal health during pregnancy and reduce the risk of developing gestational diabetes mellitus.

Placental single cell transcriptomics: Opportunities for endocrine disrupting chemical toxicology

The placenta performs essential biologic functions for fetal development throughout pregnancy. Placental dysfunction is at the root of multiple adverse birth outcomes such as intrauterine growth restriction, preeclampsia, and preterm birth. Exposure to endocrine disrupting chemicals during pregnancy can cause placental dysfunction, and many prior human studies have examined molecular changes in bulk placental tissues. Placenta-specific cell types, including cytotrophoblasts, syncytiotrophoblasts, extravillous trophoblasts, and placental resident macrophage Hofbauer cells play unique roles in placental development, structure, and function. Toxicant-induced changes in relative abundance and/or impairment of these cell types likely contribute to placental pathogenesis. Although gene expression insights gained from bulk placental tissue RNA-sequencing data are useful, their interpretation is limited because bulk analysis can mask the effects of a chemical on individual populations of placental cells. Cutting-edge single cell RNA-sequencing technologies are enabling the investigation of placental cell-type specific responses to endocrine disrupting chemicals. Moreover, in situ bioinformatic cell deconvolution enables the estimation of cell type proportions in bulk placental tissue gene expression data. These emerging technologies have tremendous potential to provide novel mechanistic insights in a complex heterogeneous tissue with implications for toxicant contributions to adverse pregnancy outcomes.

The role of maternal hormones in regulating autonomic functions during pregnancy

Offspring development relies on numerous physiological changes that occur in a mother's body, with hormones driving many of these adaptations. Amongst these, the physiological functions controlled by the autonomic nervous system are required for the mother to survive and are adjusted to meet the demands of the growing foetus and to ensure a successful birth. The hormones oestrogen, progesterone, and lactogenic hormones rise significantly during pregnancy, suggesting they may also play a role in regulating the maternal adaptations linked to autonomic nervous system functions, including respiratory, cardiovascular, and thermoregulatory functions. Indeed, expression of pregnancy hormone receptors spans multiple brain regions known to regulate these physiological functions. This review examines how respiratory, cardiovascular, and thermoregulatory functions are controlled by these pregnancy hormones by focusing on their action on central nervous system circuits. Inadequate adaptations in these systems during pregnancy can give rise to several pregnancy complications, highlighting the importance in understanding the mechanistic underpinnings of these changes and potentially identifying ways to treat pregnancy-associated afflictions using hormones.

Microglia depletion facilitates the display of maternal behavior and alters activation of the maternal brain network in nulliparous female rats

The peripartum period is accompanied by peripheral immune alterations to promote a successful pregnancy. We and others have also demonstrated significant neuroimmune changes that emerge during late pregnancy and persist postpartum, most prominently decreased microglia numbers within limbic brain regions. Here we hypothesized that microglial downregulation is important for the onset and display of maternal behavior. To test this, we recapitulated the peripartum neuroimmune profile by depleting microglia in non-mother (i.e., nulliparous) female rats who are typically not maternal but can be induced to behave maternally towards foster pups after repeated exposure, a process called maternal sensitization. BLZ945, a selective colony-stimulating factor 1 receptor (CSF1R) inhibitor, was administered systemically to nulliparous rats, which led to ~75% decrease in microglia number. BLZ- and vehicle-treated females then underwent maternal sensitization and tissue was stained for ∆fosB to examine activation across maternally relevant brain regions. We found BLZ-treated females with microglial depletion met criteria for displaying maternal behavior significantly sooner than vehicle-treated females and displayed increased pup-directed behaviors. Microglia depletion also reduced threat appraisal behavior in an open field test. Notably, nulliparous females with microglial depletion had decreased numbers of ∆fosB+ cells in the medial amygdala and periaqueductal gray, and increased numbers in the prefrontal cortex and somatosensory cortex, compared to vehicle. Our results demonstrate that microglia regulate maternal behavior in adult females, possibly by shifting patterns of activity in the maternal brain network.

Recalibration of the stress response system over adult development: Is there a perinatal recalibration period?

During early life-sensitive periods (i.e., fetal, infancy), the developing stress response system adaptively calibrates to match environmental conditions, whether harsh or supportive. Recent evidence suggests that puberty is another window when the stress system is open to recalibration if environmental conditions have shifted significantly. Whether additional periods of recalibration exist in adulthood remains to be established. The present paper draws parallels between childhood (re)calibration periods and the perinatal period to hypothesize that this phase may be an additional window of stress recalibration in adult life. Specifically, the perinatal period (defined here to include pregnancy, lactation, and early parenthood) is also a developmental switch point characterized by heightened neural plasticity and marked changes in stress system function. After discussing these similarities, lines of empirical evidence needed to substantiate the perinatal stress recalibration hypothesis are proposed, and existing research support is reviewed. Complexities and challenges related to delineating the boundaries of perinatal stress recalibration and empirically testing this hypothesis are discussed, as well as possibilities for future multidisciplinary research. In the theme of this special issue, perinatal stress recalibration may be a mechanism of multilevel, multisystem risk, and resilience, both intra-individually and intergenerationally, with implications for optimizing interventions.

Gestational exposure to ambient fine particulate matter disrupts maternal hepatic lipid metabolism

Pregnancy is a unique physiological stage for females as well as a vulnerable period for pollutant exposure. The effect of gestational ambient fine particulate matter (PM2.5) exposure on maternal lipid metabolism during pregnancy is rarely observed, and the mechanism is unknown. In the current study, pregnant C57BL/6 mice were randomly assigned to either ambient PM2.5 or filtered air exposure chambers since gestational day (GD) 0. Meanwhile, non-pregnant female mice were housed as controls in each exposure chamber. PM2.5 exposure exerted no significant effect on body weight gain or the body composition during pregnancy. Pregnant mice exposed to PM2.5 demonstrated improved glucose tolerance, whereas non-pregnant mice showed an increased fasting blood glucose level after PM2.5 exposure with no alterations in glucose tolerance. PM2.5 exposure exerted no significant effect on total lipid content in serum during pregnancy, while an increased serum total lipid level was found in non-pregnant mice exposed to PM2.5. PM2.5 exposure had no effect on total liver lipid levels, it increased several triacylglycerol (TAG) species and total cholesterol esters (CEs) in pregnant mice but lowered a considerable amount in non-pregnant mice' livers. Furthermore, gestational exposure to PM2.5 enhanced the expression of key enzymes in fatty acid uptake, de novo lipid synthesis, and β oxidation, and inhibited molecules for lipid export in mice liver. Conversely, PM2.5 exposure upregulated proteins involved in hepatic lipolysis and lipid export in non-pregnant mice. These results suggest that the interference of PM2.5 exposure during pregnancy on the lipid metabolism, particularly the hepatic lipid metabolism, differs from that during non-pregnancy. This study provides toxicological evidence that PM2.5 exposure during pregnancy disrupts the lipid metabolism of the liver and provides a basis for protecting vulnerable populations.

NOTCH3 signalling controls human trophoblast stem cell expansion and differentiation

Failures in growth and differentiation of the early human placenta are associated with severe pregnancy disorders such as pre-eclampsia and fetal growth restriction. However, regulatory mechanisms controlling development of placental epithelial cells, the trophoblasts, remain poorly elucidated. Using trophoblast stem cells (TSCs), trophoblast organoids (TB-ORGs) and primary cytotrophoblasts (CTBs) of early pregnancy, we herein show that autocrine NOTCH3 signalling controls human placental expansion and differentiation. The NOTCH3 receptor was specifically expressed in proliferative CTB progenitors and its active form, the nuclear NOTCH3 intracellular domain (NOTCH3-ICD), interacted with the transcriptional co-activator mastermind-like 1 (MAML1). Doxycycline-inducible expression of dominant-negative MAML1 in TSC lines provoked cell fusion and upregulation of genes specific for multinucleated syncytiotrophoblasts, which are the differentiated hormone-producing cells of the placenta. However, progenitor expansion and markers of trophoblast stemness and proliferation were suppressed. Accordingly, inhibition of NOTCH3 signalling diminished growth of TB-ORGs, whereas overexpression of NOTCH3-ICD in primary CTBs and TSCs showed opposite effects. In conclusion, the data suggest that canonical NOTCH3 signalling plays a key role in human placental development by promoting self-renewal of CTB progenitors.

Within-person associations of cortisol, dehydroepiandrosterone, and testosterone hair hormone concentrations and psychological distress in pregnant and non-pregnant women

Prenatal hair cortisol concentration is inconsistently associated with maternal psychological distress. However, prior studies have not often measured hair cortisol and maternal psychological distress prospectively over time, examined within-person associations, nor concurrently considered the complex hormonal milieu in which cortisol operates during pregnancy. We addressed these limitations and tested associations against a similar non-pregnant comparison group. Participants included 68 women (34 pregnant and 34 non-pregnant; Mage = 29.14 and 83 % White) from the Midwestern United States. Pregnant women were assessed each trimester, at 12, 26, and 38 weeks and non-pregnant women were assessed three times on the same schedule. At each assessment, participants completed measures of psychological distress and provided hair samples. The first 3 cm (from the scalp) of hair was assayed using enzyme immune-assay kits to reflect cumulative levels within the given trimester/3-month time period of cortisol, dehydroepiandrosterone (DHEA) and testosterone. Within-person associations of hair cortisol and ratio of hair cortisol-to-DHEA and cortisol-to-testosterone with psychological distress were assessed using multilevel models. There were positive within-person associations of hair cortisol with cumulative psychological distress (γ = 0.01, s.e. = 0.003, p = .049), anxiety (γ = 0.09, s.e. = 0.04, p = .046), and pregnancy-related anxiety symptoms (γ = 0.10, s.e. = 0.05, p = .041) in the pregnant sample such that on occasions when hair cortisol was higher than average so were psychological distress symptoms. No within-person associations of hair cortisol were supported in non-pregnant women although there was a negative within-person association, such that on occasions of having lower testosterone level than typical, depression symptoms were higher. There were no within-person associations of psychological distress and cortisol-to-DHEA ratio or cortisol-to-testosterone ratio in either the pregnant or non-pregnant sample. At the between person-level for pregnant women, lower cortisol levels were associated with higher perceived stress (γ = -0.28, s.e. = 0.09, p = .003) and depression symptoms (γ = -0.11, s.e. = 0.06, p = .039), whereas higher cortisol levels were associated with higher psychological distress (γ = 0.03, s.e. = 0.01, p = .010), state anxiety (γ = 0.33, s.e. = 0.13, p = .010), and depression symptoms (γ = 0.23, s.e. = 0.09, p = .017) in non-pregnant women. Modeling hair cortisol at the within-person and between-person level revealed differential findings in pregnant and non-pregnant women. Hair cortisol concentration, psychological distress, pregnancy, hormone coupling, within-person associations.

Imprinted genes and the manipulation of parenting in mammals

Genomic imprinting refers to the parent-of-origin expression of genes, which originates from epigenetic events in the mammalian germ line. The evolution of imprinting may reflect a conflict over resource allocation early in life, with silencing of paternal genes in offspring soliciting increased maternal provision and silencing of maternal genes limiting demands on the mother. Parental caregiving has been identified as an area of potential conflict, with several imprinted genes serendipitously found to directly influence the quality of maternal care. Recent systems biology approaches, based on single-cell RNA sequencing data, support a more deliberate relationship, which is reinforced by the finding that imprinted genes expressed in the offspring influence the quality of maternal caregiving. These bidirectional, reiterative relationships between parents and their offspring are critical both for short-term survival and for lifelong wellbeing, with clear implications for human health.

The physiological basis with uterine myometrium contractions from electro-mechanical/hormonal myofibril function to the term and preterm labor

Background

Most labor-related problems can be attributed to the uterine myometrium muscle, as this irritable tissue must suppress its irritability potential during pregnancy. Unfortunately, fewer studies have investigated the causes of this lack of suppression in preterm labor.

Methods

We conducted a scoping narrative review using three online databases (PubMed, Scopus, and Science Direct).

Results

The review focused on ion channel functions in the myometrium, including sodium channels [Na K-ATPase, Na-activated K channels (Slo2), voltage-gated (SCN) Na+, Na+ leaky channels, nonselective (NALCN) channels], potassium channels [KATP (Kir6) channels, voltage-dependent K channels (Kv4, Kv7, and Kv11), twin-pore domain K channels (TASK, TREK), inward rectifier Kir7.1, Ca2+-activated K+ channels with large (KCNMA1, Slo1), small (KCNN1-3), intermediate (KCNN4) conductance], and calcium channels [L-Type and T-type Ca2+ channels, calcium-activated chloride channels (CaCC)], as well as hyperpolarization-activated cation channels. These channels' functions are associated with hormonal effects such as oxytocin, estrogen/progesterone, and local prostaglandins.

Conclusion

Electromechanical/hormonal activity and environmental autocrine factors can serve as the primary practical basis for premature uterine contractions in term/preterm labor. Our findings highlight the significance of.1.the amplitude rate of hyperpolarization and the frequency of contractions,2.changes in the estrogen/progesterone ratio,3.Prostaglandins E/F involvement in initiating potential spikes and the increase of intracytoplasmic Ca2+.This narrative study highlights the range of hyperpolarization and the frequency of myometrium contractions as crucial factors. The synchronized complex progress of estrogen to progesterone ratio and prostaglandins plays a significant role in initiating potential spikes and increasing intracytoplasmic Ca2+, which further influences the contraction process during labor. Insights into myometrium physiology gained from this study may pave the way for much-needed new treatments to reduce problems associated with normal and preterm labor.

Population dynamics model for aging

The chronological age used in demography describes the linear evolution of the life of a living being. The chronological age cannot give precise information about the exact developmental stage or aging processes an organism has reached. On the contrary, the biological age (or epigenetic age) represents the true evolution of the tissues and organs of the living being. Biological age is not always linear and sometimes proceeds by discontinuous jumps. These jumps can be negative (we then speak of rejuvenation) or positive (in the event of premature aging), and they can be dependent on endogenous events such as pregnancy (negative jump) or stroke (positive jump) or exogenous ones such as surgical treatment (negative jump) or infectious disease (positive jump). The article proposes a mathematical model of the biological age by defining a valid model for the two types of jumps (positive and negative). The existence and uniqueness of the solution are solved, and its temporal dynamic is analyzed using a moments equation. We also provide some individual-based stochastic simulations.

Insulin signaling in development

Nutrient intake is obligatory for animal growth and development, but nutrients alone are not sufficient. Indeed, insulin and homologous hormones are required for normal growth even in the presence of nutrients. These hormones communicate nutrient status between organs, allowing animals to coordinate growth and metabolism with nutrient supply. Insulin and related hormones, such as insulin-like growth factors and insulin-like peptides, play important roles in development and metabolism, with defects in insulin production and signaling leading to hyperglycemia and diabetes. Here, we describe the insulin hormone family and the signal transduction pathways activated by these hormones. We highlight the roles of insulin signaling in coordinating maternal and fetal metabolism and growth during pregnancy, and we describe how secretion of insulin is regulated at different life stages. Additionally, we discuss the roles of insulin signaling in cell growth, stem cell proliferation and cell differentiation. We provide examples of the role of insulin in development across multiple model organisms: Caenorhabditis elegans, Drosophila, zebrafish, mouse and human.

The transition to motherhood: linking hormones, brain and behaviour

We are witnessing a stark increase in scientific interest in the neurobiological processes associated with pregnancy and maternity. Convergent evidence suggests that around the time of labour, first-time mothers experience a specific pattern of neuroanatomical changes that are associated with maternal behaviour. Here we provide an overview of the human neurobiological adaptations of motherhood, focusing on the interplay between pregnancy-related steroid and peptide hormones, and neuroplasticity in the brain. We discuss which brain plasticity mechanisms might underlie the structural changes detected by MRI, which hormonal systems are likely to contribute to such neuroanatomical changes and how these brain mechanisms may be linked to maternal behaviour. This Review offers an overarching framework that can serve as a roadmap for future investigations.

Assessing Knowledge on Gestational Diabetes Mellitus and Child Health

Gestational diabetes mellitus (GDM) is a diagnosis of glucose intolerance during pregnancy. The risk of type II diabetes mellitus (T2DM) and obesity for the child and mother increases when GDM develops. Preventing the development of GDM could help lower the prevalence of obesity and type II diabetes mellitus morbidity rates in children of affected mothers. The purpose of the study was to identify the awareness level of females ages 12 and 51 years, on the long-term risk of obesity and T2DM on their children in Australia and Samoa. This is a quantitative study involving 202 females, from across Australia and Samoa, between April 2021 and November 2021, comparing the level of knowledge between a developing and developed country. In Australia and Samoa, 15% (n=16) and 34% (n=33) of females respectively, were aware of the long-term complications of GDM on their children. These findings indicate that there is inadequate knowledge regarding the long-term consequences associated with GDM on both the risk for T2DM in women and the risk for long-term complications for their children. The greatest source of information in both countries was obtained from physicians or midwives, 52% (n=105). This supports the need for increased education on GDM, through social media, the internet, and community health professionals. By increasing awareness of GDM and implementing preventive strategies, it may be possible to reduce the prevalence of obesity and T2DM in Australia and Samoa.

Metabolic and feeding adjustments during pregnancy

Eating behaviours are determined by the integration of interoceptive and environmental inputs. During pregnancy, numerous physiological adaptations take place in the maternal organism to provide an adequate environment for embryonic growth. Among them, whole-body physiological remodelling directly influences eating patterns, commonly causing notable taste perception alterations, food aversions and cravings. Recurrent food cravings for and compulsive eating of highly palatable food can contribute to the development and maintenance of gestational overweight and obesity with potential adverse health consequences for the offspring. Although much is known about how maternal eating habits influence offspring health, the mechanisms that underlie changes in taste perception and food preference during pregnancy (which guide and promote feeding) are only just starting to be elucidated. Given the limited and diffuse understanding of the neurobiology of gestational eating patterns, the aim of this Review is to compile, integrate and discuss the research conducted on this topic in both experimental models and humans. This article sheds light on the mechanisms that drive changes in female feeding behaviours during distinct physiological states. Understanding these processes is crucial to improve gestational parent health and decrease the burden of metabolic and food-related diseases in future generations.

Physiological and pathological evidence of O-GlcNAcylation regulation during pregnancy related process

O-GlcNAcylation is a dynamic and reversible post-translational modification (PTM) controlled by the enzymes O-GlcNAc transferase (OGT) and O-GlcNAcase (OGA). Changes in its expression lead to a breakdown in cellular homeostasis, which is linked to several pathological processes. Placentation and embryonic development are periods of high cell activity, and imbalances in cell signaling pathways can result in infertility, miscarriage, or pregnancy complications. O-GlcNAcylation is involved in cellular processes such as genome maintenance, epigenetic regulation, protein synthesis/degradation, metabolic pathways, signaling pathways, apoptosis, and stress response. Trophoblastic differentiation/invasion and placental vasculogenesis, as well as zygote viability and embryonic neuronal development, are all dependent on O-GlcNAcylation. This PTM is required for pluripotency, which is a required condition for embryonic development. Further, this pathway is a nutritional sensor and cell stress marker, which is primarily measured by the OGT enzyme and its product, protein O-GlcNAcylation. Yet, this post-translational modification is enrolled in metabolic and cardiovascular adaptations during pregnancy. Finally, evidence of how O-GlcNAc impacts pregnancy during pathological conditions such as hyperglycemia, gestational diabetes, hypertension, and stress disorders are reviewed. Considering this scenario, progress in understanding the role of O- GlcNAcylation in pregnancy is required.

Plasma concentrations of per- and polyfluoroalkyl substances in pregnancy and breastfeeding duration in Project Viva

BACKGROUND

Per- and polyfluoroalkyl substances (PFAS) may disrupt mammary gland development and function; thereby inhibiting milk supply and breastfeeding duration. However, conclusions on the potential effects of PFAS and breastfeeding duration are limited by prior epidemiologic studies that inconsistently adjusted for past cumulative breastfeeding duration and by a lack of examination of the joint effects of PFAS mixtures.

METHODS

In Project Viva, a longitudinal cohort that enrolled pregnant participants from 1999 to 2002 in the greater Boston, MA area, we studied 1079 women who ever attempted to lactate. We investigated associations of plasma concentrations of select PFAS in early pregnancy (mean: 10.1 weeks gestation) with breastfeeding termination by 9 months, after which women typically cite self-weaning as the reason for terminating breastfeeding. We used Cox regression for single-PFAS models and quantile g-computation for mixture models, adjusting for sociodemographics, prior breastfeeding duration, and weeks of gestation at the time of blood draw.

RESULTS

We detected 6 PFAS [perfluorooctane sulfonate; perfluorooctanoate (PFOA); perfluorohexane sulfonate; perfluorononanoate; 2-(N-ethyl-perfluorooctane sulfonamido) acetate (EtFOSAA); 2-(N-methyl-perfluorooctane sulfonamide) acetate (MeFOSAA)] in >98 % of samples. Sixty percent of lactating women terminated breastfeeding by 9 months postpartum. Women with higher plasma concentrations of PFOA, EtFOSAA, and MeFOSAA had a greater hazard of terminating breastfeeding in the first 9 months postpartum [HR (95 % CI) per doubling concentration: 1.20 (1.04, 1.38) for PFOA; 1.10 (1.01, 1.20) for EtFOSAA; 1.18 (1.08, 1.30) for MeFOSAA]. In the quantile g-computation model, simultaneously increasing all PFAS in the mixture by one quartile was associated with 1.17 (95 % CI: 1.05, 1.31) greater hazard of terminating breastfeeding in the first 9 months.

CONCLUSION

Our findings suggest that exposure to PFAS may be associated with reduced breastfeeding duration and draw further attention to environmental chemicals that may dysregulate human lactation.

Mathematical modeling of calcium homeostasis in female rats: An analysis of sex differences and maternal adaptations

Calcium plays a vital role in various biological processes, including muscle contractions, blood clotting, skeletal mineralization, and cell signaling. While extracellular calcium makes up less than 1% of total body calcium, it is tightly regulated since too high or too low extracellular calcium concentration can have dangerous effects on the body. Mathematical modeling is a well-suited approach to investigate the complex physiological processes involved in calcium regulation. While mathematical models have been developed to study calcium homeostasis in male rats, none have been used to investigate known sex differences in hormone levels nor the unique physiological states of pregnancy and lactation. Calcitriol, the active form of vitamin D, plays a key role in intestinal calcium absorption, renal calcium reabsorption, and bone remodeling. It has been shown that, when compared to age-matched male rats, females have significantly lower calcitriol levels. In this study we first seek to investigate the impact of this difference as well as other known sex differences on calcium homeostasis using mathematical modeling. Female bodies differ from male bodies in that during their lifetime they may undergo massive adaptations during pregnancy and lactation. Indeed, maternal adaptations impact calcium regulation in all mammals. In pregnant rodents, intestinal absorption of calcium is massively increased in the mother's body to meet the needs of the developing fetus. In a lactating rodent, much of the calcium needs of milk are met by bone resorption, intestinal absorption, and renal calcium reabsorption. Given these observations, the goal of this project is to develop multi-scale whole-body models of calcium homeostasis that represents (1) how sex differences impact calcium homeostasis in female vs. male rats and (2) how a female body adapts to support the excess demands brought on by pregnancy and lactation. We used these models to quantify the impact of individual sex differences as well as maternal adaptations during pregnancy and lactation. Additionally, we conducted "what if" simulations to test whether sex differences in calcium regulation may enable females to better undergo maternal adaptations required in pregnancy and lactation than males.

Generating Functional Multicellular Organoids from Human Placenta Villi

The interaction between trophoblasts, stroma cells, and immune cells at the maternal-fetal interface constitutes the functional units of the placenta, which is crucial for successful pregnancy outcomes. However, the investigation of this intricate interplay is restricted due to the absence of efficient experimental models. To address this challenge, a robust, reliable methodology for generating placenta villi organoids (PVOs) from early, late, or diseased pregnancies using air-liquid surface culture is developed. PVOs contain cytotrophoblasts that can self-renew and differentiate directly, along with stromal elements that retain native immune cells. Analysis of scRNA sequencing and WES data reveals that PVOs faithfully recapitulate the cellular components and genetic alterations of the corresponding source tissue. Additionally, PVOs derived from patients with preeclampsia exhibit specific pathological features such as inflammation, antiangiogenic imbalance, and decreased syncytin expression. The PVO-based propagation of primary placenta villi should enable a deeper investigation of placenta development and exploration of the underlying pathogenesis and therapeutics of placenta-originated diseases.

Xeno-estrogenic activity of real-life mixtures of perfluoroalkylated substances in human placenta homogenates

Humans are simultaneously exposed to complex chemical mixtures, and its combined effect can affect human health. As part of the HBM4EU project, the actual mixture of perfluoroalkylated substances (PFAS) in 25 human placenta samples was extracted by chromatographic methods and assessed for xeno-estrogenic activity using two in-vitro bioassays: the estrogen receptor transactivity and the E-Screen assay. Most of the PFAS extracts displayed xeno-estrogenic activity, in one or both assays. The xeno-estrogenic activities in the two bioassays were not correlated, but both assays showed an overall negative correlation with placenta concentrations of single PFAS. Xeno-estrogenic activities were significantly related to maternal characteristics; being higher in young, smokers and primiparous women, but not with fetal growth (birth weight, birth length, head circumference, gestational age, placenta weight). The presented extraction method can be used to study the combined effect of real-life mixtures of PFAS in relation to health outcomes in large-scale human biomonitoring studies.

Placental, Foetal, and Maternal Serum Metabolomic Profiles in Pregnancy-Associated Cancer: Walker-256 Tumour Model in a Time-Course Analysis

Cancer during pregnancy presents a delicate coexistence, imposing ethical and professional challenges on both the patient and medical team. In this study, we aimed to explore in a pre-clinical model the impact of tumour evolution in serum, placental and foetal metabolomics profiles during pregnancy in a time-course manner. Pregnant Wistar rats were distributed into two experimental groups: Control (C) and Walker-256 tumour-bearing (W). The rats were euthanised on three different gestational periods: at 12 days post-conception (dpc), at 16 dpc, and at 19 dpc. Serum, placenta and foetal metabolomic profiles were performed by 1H-NMR spectra following the analyses using Chenomx NMR Analysis Software V8.3. The tumour evolution was exponential, affecting the placental metabolomic profile during all the pregnancy stages. The placental tissue in tumour-bearing dams developed at a lower speed, decreasing the foetus's weight. Associated with the serum metabolomic changes related to tumour growth, the placental metabolomic alterations impacted many metabolic pathways related to energy provision, protein synthesis and signalling, which directly harmed the foetus's development. The development of the foetus is clearly affected by the damage induced by the tumour evolution, which alters the metabolic profile of both the serum and the placenta, impairing early embryonic development.

Regulation of uterus and placenta remodeling under high estradiol levels in gestational diabetes mellitus models†

The present study aimed to investigate the regulation of placentas and uterus remodeling and involvement of estradiol in gestational diabetes mellitus. To achieve this, we established in vitro and in vivo models for gestational diabetes mellitus placentas by culturing human placental choriocarcinoma cells (BeWo) under hyperglycemic concentration and treating pregnant rats with streptozotocin. We evaluated the expression of angiogenesis-related proteins. The expression of the anti-angiogenic factor, excess placental soluble fms-like tyrosine kinase 1 was increased in our in vitro gestational diabetes mellitus model compared with the control. Moreover, the expressions of placental soluble fms-like tyrosine kinase 1 and the von Willebrand factor were also significantly elevated in the placenta of streptozotocin-treated rats. These data indicate the disruption of angiogenesis in the gestational diabetes mellitus placentas. The expression levels of connexin 43, a component of the gap junction and collagen type I alpha 2 chain, a component of the extracellular matrix, were decreased in the gestational diabetes mellitus uterus. These results suggest that uterus decidualization and placental angiogenesis are inhibited in gestational diabetes mellitus rats. Our results also showed upregulation of the expression of genes regulating estradiol synthesis as well as estrogen receptors in vivo models. Accordingly, the concentration of estradiol measured in the culture medium under hyperglycemic conditions, as well as in the serum and placenta of the streptozotocin-treated rats, was significantly elevated compared with the control groups. These results suggest that the dysregulated remodeling of the placenta and uterus may result in the elevation of estradiol and its signaling pathway in the gestational diabetes mellitus animal model to maintain pregnancy.

The Importance of Metabolic and Environmental Factors in the Occurrence of Oxidative Stress during Pregnancy

Metabolic changes in pregnant women begin in the first weeks after conception under the influence of placental hormones that affect the metabolism of all nutrients. An increased concentration of total lipids accompanies pregnancy and an increased accumulation of triglycerides in low-density lipoproteins (LDL) particles. Lipids in small dense LDL particles are more susceptible to oxidative modification than normal-density LDL particles. Unlike LDL high-density lipoproteins (HDL), lipoprotein particles have an atheroprotective role in lipid metabolism. The very growth of the fetus depends on the nutrition of both parents, so obesity is not only in the mother but also in the father. Nutritional programming of the offspring occurs through changes in lipid metabolism and leads to an increased risk for cardiometabolic diseases. Pregnancy is accompanied by an increased need for oxygen in the mitochondria of the placenta and a tendency to develop oxidative stress. Oxidative stress represents a disturbance in the balance of oxidation-reduction processes in the body that occurs due to the excessive production of free oxygen radicals that cellular homeostatic mechanisms are unable to neutralize. When the balance with the antioxidant system is disturbed, which happens when free oxygen radicals are in high concentrations, serious damage to biological molecules occurs, resulting in a series of pathophysiological and pathological changes, including cell death. Therefore, oxidative stress plays a significant role in the pathogenesis of many complications that can occur during pregnancy. The oxidative status of pregnant women is also influenced by socioeconomic living conditions, lifestyle habits, diet, smoking, and exposure to environmental air pollution. During a healthy pregnancy, the altered lipid profile and oxidative stress create an increased risk for premature birth and pregnancy-related diseases, and a predisposition to adult diseases.

Fetal manipulation of maternal metabolism is a critical function of the imprinted Igf2 gene

Maternal-offspring interactions in mammals involve both cooperation and conflict. The fetus has evolved ways to manipulate maternal physiology to enhance placental nutrient transfer, but the mechanisms involved remain unclear. The imprinted Igf2 gene is highly expressed in murine placental endocrine cells. Here, we show that Igf2 deletion in these cells impairs placental endocrine signaling to the mother, without affecting placental morphology. Igf2 controls placental hormone production, including prolactins, and is crucial to establish pregnancy-related insulin resistance and to partition nutrients to the fetus. Consequently, fetuses lacking placental endocrine Igf2 are growth restricted and hypoglycemic. Mechanistically, Igf2 controls protein synthesis and cellular energy homeostasis, actions dependent on the placental endocrine cell type. Igf2 loss also has additional long-lasting effects on offspring metabolism in adulthood. Our study provides compelling evidence for an intrinsic fetal manipulation system operating in placenta that modifies maternal metabolism and fetal resource allocation, with long-term consequences for offspring metabolic health.

Pregnancy-associated Steroid Effects on Insulin Sensitivity, Adipogenesis, and Lipogenesis: Role of Wnt/β-Catenin Pathway

Context

The shift in maternal energy metabolism characteristic of pregnancy is thought to be driven by various hormonal changes, especially of ovarian and placental steroids. Imbalances in circulating estradiol (E2) and progesterone (P4) levels during this period are often associated with metabolic disturbances leading to the development of gestational diabetes mellitus (GDM). Since abnormalities in the Wnt pathway effector transcription factor 7-like 2 (TCF7L2) are commonly associated with the occurrence of GDM, we hypothesized that the canonical or β-catenin-dependent Wnt signaling pathway mediates the metabolic actions of E2 and P4.

Objective

Our study was aimed at elucidating the metabolic function of the steroids E2 and P4, and examining the role of the canonical Wnt signaling pathway in mediating the actions of these steroids.

Methods

The ovariectomized (OVX) rat was used as a model system to study the effect of known concentrations of exogenously administered E2 and P4. Niclosamide (Nic) was administered to block Wnt signaling. 3T3-L1 cells were used to analyze changes in differentiation in the presence of the steroids or niclosamide.

Results

In the present study, we observed that E2 enhanced insulin sensitivity and inhibited lipogenesis while P4 increased lipogenic gene expression-in 3T3-L1 adipocytes, and in adipose tissue and skeletal muscle of OVX rats when the dosage of E2 and P4 mimicked that of pregnancy. Both E2 and P4 were also found to upregulate Wnt signaling. Nic nhibited the steroid-mediated increase in Wnt signaling in adipocytes and OVX rats. The insulin-sensitizing and antilipogenic actions of E2 were found to be mediated by the canonical Wnt pathway, but the effects of P4 on lipogenesis appeared to be independent of it. Additionally, it was observed that inhibition of Wnt signaling by Nic hastened adipogenic differentiation, and the inhibitory effect of E2 on differentiation was prevented by Nic.

Conclusion

The findings presented in this study highlight the role of steroids and Wnt pathway in glucose and lipid metabolism and are relevant to understanding the pathophysiology of metabolic disorders arising from hormonal disturbances.

Longitudinal Course of Sex Steroids From Pregnancy to Postpartum

CONTEXT

Sex steroids (SS) typically rise during pregnancy and decline after birth, but no consistent reference values exist for these hormonal courses. We aimed to establish an overview of SS secretion patterns during the peripartum and to better understand how SS contribute to maternal and fetal pathologies.

EVIDENCE ACQUISITION

A systematic literature search was conducted in accordance with the PRISMA guidelines using PubMed, Cochrane Library, and PsycINFO. Additionally, we conducted a supplementary manual search of references. Observational studies published in English and assessing estradiol, progesterone, and testosterone over the course of the peripartum in physically healthy female subjects were included, without restrictions on year of publication. Extracted data were analyzed descriptively and visually.

EVIDENCE SYNTHESIS

SS increase progressively during pregnancy, with an extremely wide range of reported concentrations, especially in the third trimester. In fact, reported concentrations varied up to 5000-fold at comparable measurement time points.

CONCLUSIONS

A comprehensive understanding of the influence of SS levels on associated maternal and fetal pathologies is currently hindered by 2 main factors. First, reported SS levels vary widely during the peripartum period. Second, the current state of knowledge on how SS are associated with pathologies in mothers and babies is largely based on correlational studies, and causality thus remains unclear. Consequently, we recommend the development of a systematic reference framework that follows the suggestions presented in this review. This would enable the establishment of SS reference values for a healthy population, resulting in the possibility to draw conclusions about deviations and related pathologies.

Assessment of Tissue Expression of the Oxytocin-Vasopressin Pathway in the Placenta of Women with a First-Episode Psychosis during Pregnancy

Psychosis refers to a mental health condition characterized by a loss of touch with reality, comprising delusions, hallucinations, disorganized thought, disorganized behavior, catatonia, and negative symptoms. A first-episode psychosis (FEP) is a rare condition that can trigger adverse outcomes both for the mother and newborn. Previously, we demonstrated the existence of histopathological changes in the placenta of pregnant women who suffer an FEP in pregnancy. Altered levels of oxytocin (OXT) and vasopressin (AVP) have been detected in patients who manifested an FEP, whereas abnormal placental expression of these hormones and their receptors (OXTR and AVPR1A) has been proven in different obstetric complications. However, the precise role and expression of these components in the placenta of women after an FEP have not been studied yet. Thus, the purpose of the present study was to analyze the gene and protein expression, using RT-qPCR and immunohistochemistry (IHC), of OXT, OXTR, AVP, and AVPR1a in the placental tissue of pregnant women after an FEP in comparison to pregnant women without any health complication (HC-PW). Our results showed increased gene and protein expression of OXT, AVP, OXTR, and AVPR1A in the placental tissue of pregnant women who suffer an FEP. Therefore, our study suggests that an FEP during pregnancy may be associated with an abnormal paracrine/endocrine activity of the placenta, which can negatively affect the maternofetal wellbeing. Nevertheless, additional research is required to validate our findings and ascertain any potential implications of the observed alterations.

Transcriptomic profiling reveals differential cellular response to copper oxide nanoparticles and polystyrene nanoplastics in perfused human placenta

The growing nanoparticulate pollution (e.g. engineered nanoparticles (NPs) or nanoplastics) has been shown to pose potential threats to human health. In particular, sensitive populations such as pregnant women and their unborn children need to be protected from harmful environmental exposures. However, developmental toxicity from prenatal exposure to pollution particles is not yet well studied despite evidence of particle accumulation in human placenta. Our study aimed to investigate how copper oxide NPs (CuO NPs; 10-20 nm) and polystyrene nanoplastics (PS NPs; 70 nm) impact on gene expression in ex vivo perfused human placental tissue. Whole genome microarray analysis revealed changes in global gene expression profile after 6 h of perfusion with sub-cytotoxic concentrations of CuO (10 µg/mL) and PS NPs (25 µg/mL). Pathway and gene ontology enrichment analysis of the differentially expressed genes suggested that CuO and PS NPs trigger distinct cellular response in placental tissue. While CuO NPs induced pathways related to angiogenesis, protein misfolding and heat shock responses, PS NPs affected the expression of genes related to inflammation and iron homeostasis. The observed effects on protein misfolding, cytokine signaling, and hormones were corroborated by western blot (accumulation of polyubiquitinated proteins) or qPCR analysis. Overall, the results of the present study revealed extensive and material-specific interference of CuO and PS NPs with placental gene expression from a single short-term exposure which deserves increasing attention. In addition, the placenta, which is often neglected in developmental toxicity studies, should be a key focus in the future safety assessment of NPs in pregnancy.

Maternal microbiota and gestational diabetes: impact on infant health

Gestational diabetes mellitus (GDM) is a common complication of pregnancy that has been associated with an increased risk of obesity and diabetes in the offspring. Pregnancy is accompanied by tightly regulated changes in the endocrine, metabolic, immune, and microbial systems, and deviations from these changes can alter the mother's metabolism resulting in adverse pregnancy outcomes and a negative impact on the health of her infant. Maternal microbiomes are significant drivers of mother and child health outcomes, and many microbial metabolites are likely to influence the host health. This review discusses the current understanding of how the microbiota and microbial metabolites may contribute to the development of GDM and how GDM-associated changes in the maternal microbiome can affect infant's health. We also describe microbiota-based interventions that aim to improve metabolic health and outline future directions for precision medicine research in this emerging field.

Maternal and Neonatal Factors Modulating Breast Milk Cytokines in the First Month of Lactation

Breast milk (BM) cytokines support and modulate infant immunity, being particularly relevant in premature neonates with adverse outcomes (NAO). This study aimed to examine, in a cohort of Spanish breastfeeding women, changes in BM cytokines in the first month of lactation, their modulation by neonatal factors (sex, gestational age, and NAO), maternal factors (obstetric complications, C-section, and diet), and their relationship with oxidative status. Sixty-three mother-neonate dyads were studied at days 7 and 28 of lactation. Dietary habits were assessed by a 72-h dietary recall, and the maternal dietary inflammatory index (mDII) was calculated. BM cytokines (IL-10, IL-13, IL-8, MCP-1, and TNFα) were assessed by ultra-sensitive chemiluminescence. Total antioxidant capacity was assessed by the ABTS method and lipid peroxidation by the MDA+HNE kit. From days 7 to 28 of lactation, the levels of IL-10 and TNFα remained stable, while IL-13 increased (β = 0.85 ± 0.12, p < 0.001) and IL-8 and MCP-1 levels decreased (β = -0.64 ± 0.27, p = 0.019; β = -0.98 ± 0.22, p < 0.001; respectively). Antioxidant capacity and lipid peroxidation also decrease during lactation. Neonatal sex did not influence any of the cytokines, but BM from mothers with male infants had a higher antioxidant capacity. Gestational age was associated with male sex and NAO, being inversely correlated with the BM proinflammatory cytokines IL-8, MCP-1, and TNFα. From days 7 to 28 of lactation, BM from women with NAO infants increased MCP-1 levels and had a larger drop in antioxidant capacity, with the opposite trend in lipid peroxidation. MCP-1 was also significantly higher in women undergoing C-section; this cytokine declined in women who decreased mDII during lactation, while IL-10 increased. Linear mixed regression models evidenced that the most important factors modulating BM cytokines were lactation period and gestational age. In conclusion, during the first month of lactation, BM cytokines shift towards an anti-inflammatory profile, influenced mainly by prematurity. BM MCP-1 is associated with maternal and neonatal inflammatory processes.

Distinct maternal metabolites are associated with obesity and glucose-insulin axis in the first trimester of pregnancy

BACKGROUND/OBJECTIVES

Obesity in pregnancy associates with changes in the glucose-insulin axis. We hypothesized that these changes affect the maternal metabolome already in the first trimester of human pregnancy and, thus, aimed to identify these metabolites.

PATIENTS/METHODS

We performed untargeted metabolomics (HPLC-MS/MS) on maternal serum (n = 181, gestational weeks 4⁺⁰-11⁺⁶). For further analysis, we included only non-smoking women as assessed by serum cotinine levels (ELISA) (n = 111). In addition to body mass index (BMI) and leptin as measures of obesity and adiposity, we metabolically phenotyped women by their fasting glucose, C-peptide and insulin sensitivity (IS_HOMA index). To identify metabolites (outcome) associated with BMI, leptin, glucose, C-peptide and/or IS_HOMA (exposures), we used a combination of univariable and multivariable regression analyses with multiple confounders and machine learning methods (Partial Least Squares Discriminant Analysis, Random Forest and Support Vector Machine). Additional statistical tests confirmed robustness of results. Furthermore, we performed network analyses (MoDentify package) to identify sets of correlating metabolites that are coordinately regulated by the exposures.

RESULTS

We detected 2449 serum features of which 277 were annotated. After stringent analysis, 15 metabolites associated with at least one exposure (BMI, leptin, glucose, C-peptide, IS_HOMA). Among these, palmitoleoyl ethanolamine (POEA), an endocannabinoid-like lipid endogenously synthesized from palmitoleic acid, and N-acetyl-L-alanine were consistently associated with C-peptide in all the analyses (95% CI: 0.10-0.34; effect size: 21%; p < 0.001; 95% CI: 0.04-0.10; effect size: 7%; p < 0.001). In network analysis, most features correlating with palmitoleoyl ethanolamide and N-acetyl-L-alanine and associated with C-peptide, were amino acids or dipeptides (n = 9, 35%), followed by lipids (n = 7, 27%).

CONCLUSIONS

We conclude that the metabolome of pregnant women with overweight/obesity is already altered early in pregnancy because of associated changes of C-peptide. Changes of palmitoleoyl ethanolamide concentration in pregnant women with obesity-associated hyperinsulinemia may reflect dysfunctional endocannabinoid-like signalling.

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.

IGF2 May Enhance Placental Fatty Acid Metabolism by Regulating Expression of Fatty Acid Carriers in the Growth of Fetus and Placenta during Late Pregnancy in Pigs

Fatty acids (FAs) are essential substances for the growth and development of the fetus and placenta. The growing fetus and placenta must obtain adequate FAs received from the maternal circulation and facilitated by various placental FA carriers, including FA transport proteins (FATPs), FA translocase (FAT/CD36), and cytoplasmic FA binding proteins (FABPs). Placental nutrition transport was regulated by imprinted genes H19 and insulin-like growth factor 2 (IGF2). Nevertheless, the relationship between the expression patterns of H19/IGF2 and placental fatty acid metabolism throughout pig pregnancy remains poorly studied and unclear. We investigated the placental fatty acid profile, expression patterns of FA carriers, and H19/IGF2 in the placentae on Days 40 (D40), 65 (D65), and 95 (D95) of pregnancy. The results showed that the width of the placental folds and the number of trophoblast cells of D65 placentae were significantly increased than those of D40 placentae. Several important long-chain FAs (LCFAs), including oleic acid, linoleic acid, arachidonatic acid, eicosapentaenoic acid, and docosatetraenoic acid, in the pig placenta showed dramatically increased levels throughout pregnancy. The pig placenta possessed higher expression levels of CD36, FATP4, and FABP5 compared with other FA carriers, and their expression levels had significantly upregulated 2.8-, 5.6-, and 12.0-fold from D40 to D95, respectively. The transcription level of IGF2 was dramatically upregulated and there were corresponding lower DNA methylation levels in the IGF2 DMR2 in D95 placentae relative to D65 placentae. Moreover, in vitro experimentation revealed that the overexpression of IGF2 resulted in a significant increase in fatty acid uptake and expression levels of CD36, FATP4, and FABP5 in PTr2 cells. In conclusion, our results indicate that CD36, FATP4, and FABP5 may be important regulators that enhance the transport of LCFAs in the pig placenta and that IGF2 may be involved in FA metabolism by affecting the FA carriers expression to support the growth of the fetus and placenta during late pregnancy in pigs.

Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women

Maternal obesity and gestational diabetes mellitus (GDM) are associated with insulin resistance and health risks for mother and offspring. Obesity is also characterized by low-grade inflammation, which in turn, impacts insulin sensitivity. The placenta secretes inflammatory cytokines and hormones that influence maternal glucose and insulin handling. However, little is known about the effect of maternal obesity, GDM and their interaction, on placental morphology, hormones and inflammatory cytokines. In a South African cohort of non-obese and obese pregnant women with and without GDM, this study examined placental morphology using stereology, placental hormone and cytokine expression using real-time PCR, western blotting and immunohistochemistry, and circulating TNFα and IL-6 concentrations using ELISA. Placental expression of endocrine and growth factor genes was not altered by obesity or GDM. However, LEPTIN gene expression was diminished, syncytiotrophoblast TNFα immunostaining elevated and stromal and fetal vessel IL-6 staining reduced in the placenta of obese women in a manner that was partly influenced by GDM status. Placental TNFα protein abundance and maternal circulating TNFα concentrations were reduced in GDM. Both maternal obesity and, to a lesser extent, GDM were accompanied by specific changes in placental morphometry. Maternal blood pressure and weight gain and infant ponderal index were also modified by obesity and/or GDM. Thus, obesity and GDM have specific impacts on placental morphology and endocrine and inflammatory states that may relate to pregnancy outcomes. These findings may contribute to developing placenta-targeted treatments that improve mother and offspring outcomes, which is particularly relevant given increasing rates of obesity and GDM worldwide. KEY POINTS: Rates of maternal obesity and gestational diabetes (GDM) are increasing worldwide, including in low-middle income countries (LMIC). Despite this, much of the work in the field is conducted in higher-income countries. In a well-characterised cohort of South African women, this study shows that obesity and GDM have specific impacts on placental structure, hormone production and inflammatory profile. Moreover, such placental changes were associated with pregnancy and neonatal outcomes in women who were obese and/or with GDM. The identification of specific changes in the placenta may help in the design of diagnostic and therapeutic approaches to improve pregnancy and neonatal outcomes with particular significant benefit in LMICs.