Maternal psychosocial stress during pregnancy alters the epigenetic signature of the glucocorticoid receptor gene promoter in their offspring: a meta-analysis

Evaluating the challenges and reproducibility of studies investigating DNA methylation signatures of psychological stress

Psychological stress can increase the risk of a wide range of negative health outcomes. Studies have been completed to determine if DNA methylation changes occur in the human brain because of stress and are associated with long-term effects and disease, but results have been inconsistent. Human candidate gene studies (150) and epigenome-wide association studies (67) were systematically evaluated to assess how DNA methylation is impacted by stress during the prenatal period, early childhood and adulthood. The association between DNA methylation of NR3C1 exon 1F and child maltreatment and early life adversity was well demonstrated, but other genes did not exhibit a clear association. The reproducibility of individual CpG sites in epigenome-wide association studies was also poor. However, biological pathways, including stress response, brain development and immunity, have been consistently identified across different stressors throughout the life span. Future studies would benefit from the increased sample size, longitudinal design, standardized methodology, optimal quality control, and improved statistical procedures.

No long-term effects of antenatal synthetic glucocorticoid exposure on epigenetic regulation of stress-related genes

Antenatal synthetic glucocorticoid (sGC) treatment is a potent modifier of the hypothalamic-pituitary-adrenal (HPA) axis. In this context, epigenetic modifications are discussed as potential regulators explaining how prenatal exposure to GCs might translate into persistent changes of HPA axis "functioning". The purpose of this study was to investigate whether DNA methylation and gene expression profiles of stress-associated genes (NR3C1; FKBP5; SLC6A4) may mediate the persistent effects of sGC on cortisol stress reactivity that have been previously observed. In addition, hair cortisol concentrations (hairC) were investigated as a valid biomarker of long-term HPA axis activity. This cross-sectional study comprised 108 term-born children and adolescents, including individuals with antenatal GC treatment and controls. From whole blood, DNA methylation was analyzed by targeted deep bisulfite sequencing. Relative mRNA expression was determined by RT-qPCR experiments and qBase analysis. Acute stress reactivity was assessed by the Trier Social Stress Test (TSST) measuring salivary cortisol by ELISA and hairC concentrations were determined from hair samples by liquid chromatography coupled with tandem mass spectrometry. First, no differences in DNA methylation and mRNA expression levels of the stress-associated genes between individuals treated with antenatal sGC compared to controls were found. Second, DNA methylation and mRNA expression levels were neither associated with cortisol stress reactivity nor with hairC. These findings do not corroborate the belief that DNA methylation and mRNA expression profiles of stress-associated genes (NR3C1; FKBP5; SLC6A4) play a key mediating role of the persistent effects of sGC on HPA axis functioning.

Inheritance of hormonal stress response and temperament in infant rhesus macaques (Macaca Mulatta): Nonadditive and sex-specific effects

OBJECTIVE

Early life interindividual variation in hypothalamic-pituitary-adrenal (HPA) reactivity to stress is predictive of later life psychological and physical well-being, including the development of many pathological syndromes that are often sex-biased. A complex and interactive set of environmental and genetic causes for such variation has been implicated by previous studies, though little attention has been paid to nonadditive effects (e.g. dominance, X-linked) or sex-specific genetic effects.

METHOD

We used a large pedigreed sample of captive 3-4 months old infant rhesus macaques (N = 2,661, 54% female) to fit univariate and multivariate linear mixed quantitative genetic models for four longitudinal blood cortisol samples and three reliable ratings of infant temperament (nervousness, gentleness, confidence) during a mother-infant separation protocol.

RESULTS

Each trait had a moderate narrow-sense heritability (h², 0.26-0.46), but dominance effects caused the first two cortisol samples to have much larger broad-sense heritabilities (H², 0.57 and 0.77). We found no evidence for X-linked variance or common maternal environment variance. There was a sex difference in heritability of the first cortisol sample (h_f² < h_m²), suggesting differing genetic architecture of perception of maternal separation and relocation during infancy. Otherwise, genetic covariance matrices for the sexes were very similar. Genetic correlations between cortisol levels and temperament were weak (< |0.4|) but stronger than residual or phenotypic correlations.

CONCLUSIONS

HPA reactivity and temperament had a primarily additive genetic basis in infant macaques, but there were important complexities to the genetic architecture of including genetic dominance and sex differences in heritability at this early life stage. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Strengthening Population Health Perspectives in Physical Therapist Practice Using Epigenetics

Health starts where we live, learn, work, and play. Population health represents a unifying paradigm for understanding systematic variations in health and related factors, informing integrated action, and reducing health disparities. The pathways connecting social, environmental, and structural factors and various health outcomes have been illuminated by the emergence of epigenetic and epigenomic research, further bolstering the value of population health perspectives in supporting clinical practice, community-based programs, and societal policies. The purpose of this perspective is to consider the placement of epigenetic and epigenomic insights within a population health framework to strengthen the physical therapy profession's understanding of variations in health, inform integrated action, and further justify our role in reducing health-related disparities.

Synergistic gene regulation by thyroid hormone and glucocorticoid in the hippocampus

The hippocampus is considered the center for learning and memory in the brain, and its development and function is greatly affected by the thyroid and stress axes. Thyroid hormone (TH) and glucocorticoids (GC) are known to have a synergistic effect on developmental programs across several vertebrate species, and their effects on hippocampal structure and function are well-documented. However, there are few studies that focus on the processes and genes that are cooperatively regulated by the two hormone axes. Cross-regulation of the thyroid and stress axes in the hippocampus occurs on multiple levels such that TH can regulate the expression of the GC receptor (GR) while GC can modulate tissue sensitivity to TH by controlling the expression of TH receptor (TR) and enzymes involved in TH biosynthesis. Thyroid hormone and GC are also known to synergistically regulate the transcription of genes associated with neuronal function and development. Synergistic gene regulation by TH and GC may occur through the direct, cooperative action of TR and GR on common target genes, or by indirect mechanisms involving gene regulatory cascades activated by TR and GR. In this chapter, we describe the known physiological effects and underlying molecular mechanisms of TH and GC synergistic gene regulation in the hippocampus.

Effects of maternal psychological distress and perception of COVID-19 on prenatal attachment in a large sample of Italian pregnant women

BACKGROUND

Evidence concerning the impact of COVID-19-related stress exposure on prenatal attachment in pregnant women is unknown. In this study we sought to assess the effect of psychological distress and risk perception of COVID-19 on prenatal attachment in a Italian sample of pregnant women.

METHODS

1179 pregnant women completed an anonymous online survey and self-report questionnaires measuring socio-demographic and obstetric characteristics, psychological distress (STAI Form Y-1-2 and BDI-II), prenatal attachment (PAI) and risk perception of COVID-19. Data were collected from March 2020 to April 2020 referring to the national lockdown period.

RESULTS

After adjusting for the socio-demographic and obstetric factors in the multivariable analysis, we found out the state anxiety was shown to be a significant predictor (p < 0001) of prenatal attachment. Moreover, the COVID-19-risk perception positively moderate the relationship between trait anxiety and prenatal attachment (p=0008), indicating that when COVID-19-risk perception is high, the effects of trait anxiety on prenatal attachment is attenuated. The synergistic effect between STAI Form Y-1 and COVID-19-risk perception index on PAI is partially mediated by STAI Form Y-2 score.

CONCLUSIONS

Findings from this study showed that state anxiety related to COVID-19 outbreak in pregnant women may affect the prenatal attachment process of the expectant mother negatively. However, an adequate and functional perception of COVID-19 could enhance prenatal attachment. These results underline the importance of monitoring the prenatal attachment process and the mother's mental health during pandemics, to safeguard maternal and infant mental health.

Prenatal Lead and Depression Exposures Jointly Influence Birth Outcomes and NR3C1 DNA Methylation

Many gestational exposures influence birth outcomes, yet the joint contribution of toxicant and psychosocial factors is understudied. Moreover, associated gestational epigenetic mechanisms are unknown. Lead (Pb) and depression independently influence birth outcomes and offspring NR3C1 (glucocorticoid receptor) DNA methylation. We hypothesized that gestational Pb and depression would jointly influence birth outcomes and NR3C1 methylation. Pregnancy exposure information, DNA methylation, and birth outcome data were collected prospectively from n = 272 mother–infant pairs. Factor analysis was used to reduce the dimensionality of NR3C1. Multivariable linear regressions tested for interaction effects between gestational Pb and depression exposures with birth outcomes and NR3C1. Interaction effects indicated that higher levels of Pb and depression jointly contributed to earlier gestations, smaller infant size at birth, and asymmetric fetal growth. Pb and depression were also jointly associated with the two primary factor scores explaining the most variability in NR3C1 methylation; NR3C1 scores were associated with some infant outcomes, including gestational age and asymmetric fetal growth. Pb and depression can cumulatively influence birth outcomes and epigenetic mechanisms, which may lay the foundation for later health risk. As toxicants and social adversities commonly co-occur, research should consider the life course consequences of these interconnected exposures.

Advancing health through research: A scoping review of and model for adjunctive psychosocial interventions to improve outcomes for perinatal women with bipolar disorder

BACKGROUND

We aimed to identify randomized clinical trials (RCTs) which evaluated the efficacy of adjunctive psychosocial interventions to improve outcomes during the perinatal period for women with bipolar disorder (BD).

METHODS

We scanned the literature to identify RCTs evaluating the efficacy of adjunctive psychosocial therapies or interventions provided during the perinatal period to women with BD. We searched from 1946 to July 2020 using Embase, Ovid Medline, PsycINFO, and Scopus. We then searched for future, current, and recently completed RCTs described on www.ClinicalTrials.gov.

RESULTS

This scoping review (1946 - July 2020) revealed no published RCTs for this population. The findings expose an important gap in research and knowledge, as well as a health disparity.

CONCLUSION

We heuristically tied a mechanistic stress reduction model to relevant findings. The initial hypotheses are informed by effective stress reducing psychosocial interventions for: a) people with BD outside the perinatal period and b) perinatal women with major depressive disorder (MDD may improve the health of perinatal women with BD). We hypothesize that the perinatal trajectory of health for women with BD will improve by adding psychosocial interventions or therapies to treatment as usual. We propose maternal stress reduction as a potential mediator/mechanism.

LIMITATIONS

Findings reported are limited to the methods of a scoping review. Reproductive status tends to be a missing variable; we highlight the need for its inclusion. Interdisciplinary, collaborative research to improve the treatment outcome for perinatal women with BD is warranted and ripe for advancement.

Environmental Influences Measured by Epigenetic Clock and Vulnerability Components at Birth Impact Clinical ASD Heterogeneity

Although Autism Spectrum Disorders (ASD) is recognized as being heavily influenced by genetic factors, the role of epigenetic and environmental factors is still being established. This study aimed to identify ASD vulnerability components based on familial history and intrauterine environmental stress exposure, explore possible vulnerability subgroups, access DNA methylation age acceleration (AA) as a proxy of stress exposure during life, and evaluate the association of ASD vulnerability components and AA to phenotypic severity measures. Principal Component Analysis (PCA) was used to search the vulnerability components from 67 mothers of autistic children. We found that PC1 had a higher correlation with psychosocial stress (maternal stress, maternal education, and social class), and PC2 had a higher correlation with biological factors (psychiatric family history and gestational complications). Comparing the methylome between above and below PC1 average subgroups we found 11,879 statistically significant differentially methylated probes (DMPs, p < 0.05). DMPs CpG sites were enriched in variably methylated regions (VMRs), most showing environmental and genetic influences. Hypermethylated probes presented higher rates in different regulatory regions associated with functional SNPs, indicating that the subgroups may have different affected regulatory regions and their liability to disease explained by common variations. Vulnerability components score moderated by epigenetic clock AA was associated with Vineland Total score (p = 0.0036, adjR² = 0.31), suggesting risk factors with stress burden can influence ASD phenotype.

Preventing Childhood Toxic Stress: Partnering With Families and Communities to Promote Relational Health

By focusing on the safe, stable, and nurturing relationships (SSNRs) that buffer adversity and build resilience, pediatric care is on the cusp of a paradigm shift that could reprioritize clinical activities, rewrite research agendas, and realign our collective advocacy. Driving this transformation are advances in developmental sciences as they inform a deeper understanding of how early life experiences, both nurturing and adverse, are biologically embedded and influence outcomes in health, education, and economic stability across the life span. This revised policy statement on childhood toxic stress acknowledges a spectrum of potential adversities and reaffirms the benefits of an ecobiodevelopmental model for understanding the childhood origins of adult-manifested disease and wellness. It also endorses a paradigm shift toward relational health because SSNRs not only buffer childhood adversity when it occurs but also promote the capacities needed to be resilient in the future. To translate this relational health framework into clinical practice, generative research, and public policy, the entire pediatric community needs to adopt a public health approach that builds relational health by partnering with families and communities. This public health approach to relational health needs to be integrated both vertically (by including primary, secondary, and tertiary preventions) and horizontally (by including public service sectors beyond health care). The American Academy of Pediatrics asserts that SSNRs are biological necessities for all children because they mitigate childhood toxic stress responses and proactively build resilience by fostering the adaptive skills needed to cope with future adversity in a healthy manner.

Maternal psychosocial risk factors and child gestational epigenetic age in a South African birth cohort study

Accelerated epigenetic aging relative to chronological age has been found to be associated with higher risk of mortality in adults. However, little is known about whether and how in utero exposures might shape child gestational epigenetic age (EA) at birth. We aimed to explore associations between maternal psychosocial risk factors and deviation in child gestational EA at birth (i.e., greater or lower EA relative to chronological age) in a South African birth cohort study-the Drakenstein Child Health Study. Maternal psychosocial risk factors included trauma/stressor exposure; posttraumatic stress disorder (PTSD); depression; psychological distress; and alcohol/tobacco use. Child gestational EA at birth was calculated using an epigenetic clock previously devised for neonates; and gestational EA deviation was calculated as the residuals of the linear model between EA and chronological gestational age. Bivariate linear regression was then used to explore unadjusted associations between maternal/child risk factors and child gestational EA residuals at birth. Thereafter, a multivariable regression method was used to determine adjusted associations. Data from 271 maternal-child dyads were included in the current analysis. In the multivariable regression model, maternal PTSD was significantly and negatively associated with child gestational EA residuals at birth (β = -1.95; p = 0.018), controlling for study site, sex of the child, head circumference at birth, birthweight, mode of delivery, maternal estimated household income, body mass index (BMI) at enrolment, HIV status, anaemia, psychological distress, and prenatal tobacco or alcohol use. Given the novelty of this preliminary finding, and its potential translational relevance, further studies to delineate underlying biological pathways and to explore clinical implications of EA deviation are warranted.

Epigenetics: A Missing Link Between Early Life Stress and Depression

Exposure to early life stress (ELS) represents a major risk factor for the development of psychiatric disorders, including depression. The susceptibility associated with ELS may result from persistent changes in gene transcription, which can occur through epigenetic mechanisms, such as DNA methylation, histone modifications, and microRNA expression. Animal models and reports in humans described that negative stimuli can alter the neurodevelopment of an individual, affecting their behavior and cognitive development. It is currently hypothesized that levels of environmental adversity in this early developmental period are able to shape the experience-dependent maturation of stress-regulating pathways leading to long-lasting alterations in stress responsivity during adulthood. Here, we review key findings from animal and clinical studies examining the effects of prenatal and postnatal environment in shaping development of the neuroendocrine regulation of stress and the role of epigenetic mechanisms in the predisposition of depression.

Placental OPRM1 DNA methylation and associations with neonatal opioid withdrawal syndrome, a pilot study

Aims:

Epigenetic variation of DNA methylation of the mu-opioid receptor gene (OPRM1) has been identified in the blood and saliva of individuals with opioid use disorder (OUD) and infants with neonatal opioid withdrawal syndrome (NOWS). It is unknown whether epigenetic variation in OPRM1 exists within placental tissue in women with OUD and whether it is associated with NOWS outcomes. In this pilot study, the authors aimed to 1) examine the association between placental OPRM1 DNA methylation levels and NOWS outcomes, and 2) compare OPRM1 methylation levels in opioid-exposed versus non-exposed control placentas.

Methods:

Placental tissue was collected from eligible opioid (n = 64) and control (n = 29) women after delivery. Placental DNA was isolated and methylation levels at six cytosine-phosphate-guanine (CpG) sites within the OPRM1 promoter were quantified. Methylation levels were evaluated for associations with infant NOWS outcome measures: need for pharmacologic treatment, length of hospital stay (LOS), morphine treatment days, and treatment with two medications. Regression models were created and adjusted for clinical co-variates. Methylation levels between opioid and controls placentas were also compared.

Results:

The primary opioid exposures were methadone and buprenorphine. Forty-nine (76.6%) of the opioid-exposed infants required pharmacologic treatment, 10 (15.6%) two medications, and average LOS for all opioid-exposed infants was 16.5 (standard deviation 9.7) days. There were no significant associations between OPRM1 DNA methylation levels in the six CpG sites and any NOWS outcome measures. No significant differences were found in methylation levels between the opioid and control samples.

Conclusions:

No significant associations were found between OPRM1 placental DNA methylation levels and NOWS severity in this pilot cohort. In addition, no significant differences were seen in OPRM1 methylation in opioid versus control placentas. Future association studies examining methylation levels on a genome-wide level are warranted.

Inhibition of mechanistic target of rapamycin signaling decreases levels of O-GlcNAc transferase and increases serotonin release in the human placenta

Changes in placental function, in particular down-regulation of placental O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) in response to maternal stress and increased placental secretion of serotonin into the fetal circulation following maternal infection, have been mechanistically linked to adverse neurodevelopment in mice. We hypothesized that mechanistic target of rapamycin (mTOR) signaling is a key regulator of trophoblast serotonin synthesis and OGT protein expression and that serotonin is secreted by the human placenta into the fetal circulation. Placental homogenates (n=46) from elective terminations at 8-22 weeks of gestation and from healthy-term women were sexed and the protein levels of OGT and enzymes involved in serotonin synthesis was determined. Primary human trophoblast (PHT) cells were isolated from normal term placenta (n=27), cultured and transfected (n=8) with siRNA targeting a scramble sequence (control), raptor (inhibits mTOR Complex 1 (mTORC1)), or rictor (inhibits mTOR Complex 2 (mTORC2)). Subsequently, conditioned media and PHT cell lysates were collected. Free serotonin concentration was measured using ELISA in cell culture media and in platelet-depleted normal term umbilical vein and artery plasma (n=38). Both mTORC1 and mTORC2 inhibition down-regulated OGT levels in PHT cells. The level of serotonin synthesis enzyme tryptophan hydroxylase (TPH-1) was higher in early gestation female placentas and at term serotonin concentration was three-fold higher in the umbilical vein than in the umbilical artery. Inhibition of mTORC2, but not mTORC1, increased cultured PHT cell serotonin secretion. Our data are consistent with the model that mTOR signaling is a key regulator of trophoblast serotonin synthesis and OGT protein expression.

Biopsychosocial correlates of psychological distress in Latina mothers

BACKGROUND

Few studies have explored the relationship between psychological, psychosocial and biological factors among Latinas. An integrated understanding of how these factors associate with psychological distress is necessary for the development of culturally relevant screening tools and interventions. The study aim was to examine the relationships among (a) psychological distress symptoms, (b) psychosocial factors (discrimination, acculturation, acculturative stress, economic hardship), and (c) biological (DNA methylation of stress-related genes) factors among Latinas during pregnancy and postpartum period.

METHODS

A sample of 150 pregnant Latinas completed the Inventory of Depression and Anxiety Symptoms II (IDAS-II), psychosocial questionnaires (discrimination, acculturation, acculturative stress, economic hardship) before (24-32 weeks) and after gestation (4-6 weeks postpartum). Blood samples were collected between 24-32 weeks gestation. Correlations were determined between psychosocial and biological measures and psychological distress measures. Multivariable linear regression models were conducted to assess the relationships between IDAS and stressors.

RESULTS

Several correlations among psychosocial measures,DNA methylation factors and IDAS-II variables were identified. Among the psychosocial measures, everyday discrimination was the most strongly and consistently associated with IDAS-II. DNA methylation of NR3C1 affects the associations between psychological and psychosocial distress.

LIMITATIONS

We only assessed DNA methylation during pregnancy and focused on four HPA-related genes. Longitudinal assessment of DNA methylation and genome-wide analysis can provide a better picture of the role of methylation in psychological distress.

CONCLUSIONS

This work may assist clinicians and policy makers in effectively recognizing and preventing maternal mental health disparities based on discrimination and other psychosocial stressors in at-risk groups.

Prenatal maternal distress and immune cell epigenetic profiles at 3-months of age

BACKGROUND

Prenatal maternal distress predicts altered offspring immune outcomes, potentially via altered epigenetics. The role of different kinds of prenatal maternal distress on DNA methylation profiles is not understood.

METHODS

A sample of 117 women (APrON cohort) were followed from pregnancy to the postpartum period. Maternal distress (depressive symptoms, pregnancy-specific anxiety, stressful life events) were assessed mid-pregnancy, late-pregnancy, and 3-months postpartum. DNA methylation profiles were obtained from 3-month-old blood samples. Principal component analysis identified two epigenetic components, characterized as Immune Signaling and DNA Transcription through gene network analysis. Covariates were maternal demographics, pre-pregnancy body mass index, child sex, birth gestational age, and postpartum maternal distress. Penalized regression (LASSO) models were used.

RESULTS

Late-pregnancy stressful life events, b = 0.006, early-pregnancy depressive symptoms, b = 0.027, late-pregnancy depressive symptoms, b = 0.014, and pregnancy-specific anxiety during late pregnancy, b = -0.631, were predictive of the Immune Signaling component, suggesting that these aspects of maternal distress could affect methylation in offspring immune signaling pathways. Only early-pregnancy depressive symptoms was predictive of the DNA Transcription component, b = -0.0004, suggesting that this aspect of maternal distress is implicated in methylation of offspring DNA transcription pathways.

CONCLUSIONS

Exposure timing and kind of prenatal maternal distress could matter in the prediction of infant immune epigenetic profiles.

A Pre-registered Meta-analysis Based on Three Empirical Studies Reveals No Association Between Prenatal (Amniotic) Cortisol Exposure and Fluctuating Asymmetry in Human Infants

Developmental instability (DI) reflects an organism’s inability to develop an ideal phenotype when challenged by genetic and environmental insults. DI can be estimated via the proxy measure of fluctuating asymmetry (FA), i.e., the small random deviations from perfect bilateral symmetry observed in the morphology of paired traits. The mechanisms involved in the genesis of FA in human populations are relatively unknown, though animal research indicates that hormonal processes may be involved. As maternal stress during pregnancy is detrimental to various developmental processes, elevated prenatal cortisol may represent a causal factor in the subsequent emergence of an asymmetrical phenotype. The main purpose of this pre-registered meta-analysis based on three empirical studies was to investigate whether mid-trimester amniotic cortisol levels predict subsequent FA in finger lengths of infants from Germany, Portugal, and the UK. No statistically significant relationships were observed, and meta-analytic combination of the effect size estimates yielded a null result. We did, however, detect significant positive correlations between the cortisol present in the amniotic fluid and maternal plasma in the Portuguese cohort, and observed that FA in the German cohort was significantly lower at 70-months than at either 9- or 20-months. Taken together, the current findings run contrary to animal research showing that elevated prenatal corticosterone exposure leads to increased FA. However, this may be because a single cortisol assay obtained via amniocentesis is an inadequate proxy for average gestational exposure, and/or that prenatal cortisol levels at an earlier (i.e., first rather than second trimester) stage of pregnancy is what explains variance in subsequent FA.

Premature Birth and Developmental Programming: Mechanisms of Resilience and Vulnerability

The third trimester of pregnancy represents a sensitive phase for infant brain plasticity when a series of fast-developing cellular events (synaptogenesis, neuronal migration, and myelination) regulates the development of neural circuits. Throughout this dynamic period of growth and development, the human brain is susceptible to stress. Preterm infants are born with an immature brain and are, while admitted to the neonatal intensive care unit, precociously exposed to stressful procedures. Postnatal stress may contribute to altered programming of the brain, including key systems such as the hypothalamic-pituitary-adrenal axis and the autonomic nervous system. These neurobiological systems are promising markers for the etiology of several affective and social psychopathologies. As preterm birth interferes with early development of stress-regulatory systems, early interventions might strengthen resilience factors and might help reduce the detrimental effects of chronic stress exposure. Here we will review the impact of stress following premature birth on the programming of neurobiological systems and discuss possible stress-related neural circuits and pathways involved in resilience and vulnerability. Finally, we discuss opportunities for early intervention and future studies.

Role of DNA Methylation in Mediating Genetic Risk of Psychiatric Disorders

Psychiatric disorders are common, complex, and heritable conditions estimated to be the leading cause of disability worldwide. The last decade of research in genomics of psychiatry, performed by multinational, and multicenter collaborative efforts on hundreds of thousands of mental disorder cases and controls, provided invaluable insight into the genetic risk variants of these conditions. With increasing cohort sizes, more risk variants are predicted to be identified in the near future, but there appears to be a knowledge gap in understanding how these variants contribute to the pathophysiology of psychiatric disorders. Majority of the identified common risk single-nucleotide polymorphisms (SNPs) are non-coding but are enriched in regulatory regions of the genome. It is therefore of great interest to study the impact of identified psychiatric disorders' risk SNPs on DNA methylation, the best studied epigenetic modification, playing a pivotal role in the regulation of transcriptomic processes, brain development, and functioning. This work outlines the mechanisms through which risk SNPs can impact DNA methylation levels and provides a summary of current evidence on the role of DNA methylation in mediating the genetic risk of psychiatric disorders.

"Mombrain and Sticky DNA": The Impacts of Neurobiological and Epigenetic Framings of Motherhood on Women's Subjectivities

The fields of epigenetics and neuroscience have come to occupy a significant place in individual and public life in biomedicalized societies. Social scientists have argued that the primacy and popularization of the "neuro" has begun to shape how patients and other lay people experience themselves and their lifeworlds in increasingly neurological and genetic terms. Pregnant women and new mothers have become an important new target for cutting edge neuroscientific and epigenetic research, with the Internet constituting a highly active space for engagement with knowledge translations. In this paper, we analyze the reception by women in North America of translations of nascent epigenetic and neuroscientific research. We conducted three focus groups with pregnant women and new mothers. The study was informed by a prior scoping investigation of online content. Our focus group findings record how engagement with translations of epigenetic and neuroscientific research impact women's perinatal experience, wellbeing, and self-construal. Three themes emerged in our analysis: (1) A kind of brain; (2) The looping effects of biomedical narratives; (3) Imprints of past experience and the management of the future. This data reveals how mothers engage with the neurobiological style-of-thought increasingly characteristic of public health and popular science messaging around pregnancy and motherhood. Through the molecularization of pregnancy and child development, a typical passage of life becomes saturated with "susceptibility," "risk," and the imperative to preemptively make "healthy' choices." This, in turn, redefines and shapes the experience of what it is to be a "good," "healthy," or "responsible" mother/to-be.

Gaining a deeper understanding of social determinants of preterm birth by integrating multi-omics data

In the US, high rates of preterm birth (PTB) and profound Black-White disparities in PTB have persisted for decades. This review focuses on the role of social determinants of health (SDH), with an emphasis on maternal stress, in PTB disparity and biological embedding. It covers: (1) PTB disparity in US Black women and possible contributors; (2) the role of SDH, highlighting maternal stress, in the persistent racial disparity of PTB; (3) epigenetics at the interface between genes and environment; (4) the role of the genome in modifying maternal stress-PTB associations; (5) recent advances in multi-omics studies of PTB; and (6) future perspectives on integrating multi-omics with SDH to elucidate the Black-White disparity in PTB. Available studies have indicated that neither environmental exposures nor genetics alone can adequately explain the Black-White PTB disparity. Preliminary yet promising findings of epigenetic and gene-environment interaction studies underscore the value of integrating SDH with multi-omics in prospective birth cohort studies, especially among high-risk Black women. In an era of rapid advancements in biomedical sciences and technologies and a growing number of prospective birth cohort studies, we have unprecedented opportunities to advance this field and finally address the long history of health disparities in PTB. IMPACT: This review provides an overview of social determinants of health (SDH) with a focus on maternal stress and its role on Black-White disparity in preterm birth (PTB). It summarizes the available literature on the interplay of maternal stress with key biological layers (e.g., individual genome and epigenome in response to environmental stressors) and significant knowledge gaps. It offers perspectives that such knowledge may provide deeper insight into how SDH affects PTB and why some women are more vulnerable than others and underscores the critical need for integrating SDH with multi-omics in prospective birth cohort studies, especially among high-risk Black women.

Central and peripheral stress-induced epigenetic mechanisms of resilience

PURPOSE OF REVIEW

Resilience is an adaptation process presented by an individual despite facing adversities. Epigenetic changes, such as histone acetylation/methylation and DNA methylation, have been demonstrated to mediate stress response. In this review, we summarize recent findings on epigenetic mechanisms contributing to stress resilience.

RECENT FINDINGS

Epigenetic modifications of genes involved in synaptic plasticity, endocrine, immune, and vascular systems are linked to resilience. For instance, increased DNA methylation of the nonneuronal growth factor Gdnf in specific brain regions promotes stress resilience. Additionally, high DNA methylation at the glucocorticoid receptor gene was associated with resilience in both rodents and humans. At the immune level, chronic stress induces increased DNA methylation at IL6 gene, a mediator of stress vulnerability. Moreover, epigenetic adaptations of the blood--brain barrier have been recently associated with stress resilience, which could lead to innovative therapeutic approaches to treat depression.

SUMMARY

Identification of both central and peripheral epigenetic changes promoting stress resilience represent promising novel targets in the development of preventive and personalized medicine. Nevertheless, more research is needed to establish sex specific differences and to identify novel epigenetic mechanisms, such as serotonylation and dopaminylation, that hold great promises for the field of psychiatry.

Assessing Stress in Pregnancy and Postpartum: Comparing Measures

Introduction

Measuring early-life psychosocial stress is complicated by methodological challenges. This paper compares three survey instruments for the assessment of life in pregnancy/postpartum and investigates the effects of the timing of early-life stress for emotional/behavioral difficulties (EBD) of offspring during mid/late childhood and adolescence.

Methods

Observational data were obtained from the European Longitudinal Cohort Study of Pregnancy and Childhood (ELSPAC-CZ), which included 4811 pregnancies in two Czech metropolitan areas. We used data collected between 1991 and 2010 at 20 weeks of pregnancy (T1), after delivery (T2), at 6 months postpartum (T3), and at child’s age of 7 years (T4), 11 years (T5), 15 years (T6), and 18 years (T7). Life stress was assessed with (1) the Edinburgh Postnatal Depression Scale (EPDS), (2) a stressful life events (SLE) count based on 42-item inventory, and (3) the SLE measure weighted by perceived stressfulness (PS). Each stress measure was administered at T1, T2, and T3. Child’s EBD were assessed with the Strengths and Difficulties Questionnaire at T4, T5, T6, and T7.

Results

Each stress measure independently predicted long-term EBD. The best data fit was obtained in a model combining EPDS and SLE. Effect sizes for SLEs decreased between the first half of pregnancy and postpartum, while the effect of EPDS increased.

Discussion

SLE-based methods capture an aspect of perinatal stress not adequately assessed by EPDS. Combination of psychological distress measures and SLE-based measures is optimal in predicting EBD of the child. Stress measures based on SLE are suitable for early pregnancy, while self-reports of depressive symptoms may perform better in postpartum.

Chronic stress and adipose tissue in the anorexic state: endocrine and epigenetic mechanisms

Although adipose tissue metabolism in obesity has been widely studied, there is limited research on the anorexic state, where the endocrine system is disrupted by reduced adipose tissue mass and there are depot-specific changes in adipocyte type and function. Stress exposure at different stages of life can alter the balance between energy intake and expenditure and thereby contribute to the pathogenesis of anorexia nervosa. This review integrates information from human clinical trials to describe endocrine, genetic and epigenetic aspects of adipose tissue physiology in the anorexic condition. Changes in the hypothalamus-pituitary-thyroid, -adrenal, and -gonadal axes and their relationships to appetite regulation and adipocyte function are discussed. Because of the role of stress in triggering or magnifying anorexia, and the dynamic but also persistent nature of environmentally-induced epigenetic modifications, epigenetics is likely the link between stress and long-term changes in the endocrine system that disrupt homoeostatic food intake and adipose tissue metabolism. Herein, we focus on the adipocyte and changes in its function, including alterations reinforced by endocrine disturbance and dysfunctional adipokine regulation. This information is critical because of the poor understanding of anorexic pathophysiology, due to the lack of suitable research models, and the complexity of genetic and environmental interactions.

Associations Between Maternal Community Deprivation and Infant DNA Methylation of the SLC6A4 Gene

Introduction: Poverty is negatively associated with health and developmental outcomes. DNA methylation (DNAm) has been proposed as a mechanism that underlies the association between adversity experienced by mothers in poverty and health and developmental outcomes in their offspring. Previous studies have identified associations between individual-level measures of stress and adversity experienced by a mother during pregnancy and infant DNAm. We hypothesized that independent of individual stresses, a mother's community-level deprivation while she is pregnant may also be associated with DNAm among the genes of her offspring that are related to stress response and/or development. Methods: Pregnant mothers (N = 53) completed assessments that measured stress, adversity, and mental health. To evaluate community-level deprivation, mothers' addresses were linked to census-level socioeconomic measures including a composite index of deprivation that combines multiple community-level indicators such as income and highest level of education received. Infant buccal cells were collected at about age 4 weeks to measure DNAm of candidate genes including NR3C1, SCG5, and SLC6A4, which are associated with the stress response and or social and emotional development. Multivariable models were employed to evaluate the association between maternal community deprivation and infant DNAm of candidate genes. Results: No significant associations were identified between maternal community-level deprivation and the methylation of NR3C1 or SCG5, however, maternal community-level deprivation was significantly associated with higher mean methylation across 8 CpG sites in SLC6A4. Conclusion: This study identified an association between community-level measures of deprivation experienced by a mother during pregnancy and DNAm in their offspring. These findings may have implications for understanding how the community context can impact early biology and potential function in the next generation.

Food Addiction and Psychosocial Adversity: Biological Embedding, Contextual Factors, and Public Health Implications

The role of stress, trauma, and adversity particularly early in life has been identified as a contributing factor in both drug and food addictions. While links between traumatic stress and substance use disorders are well documented, the pathways to food addiction and obesity are less established. This review focuses on psychosocial and neurobiological factors that may increase risk for addiction-like behaviors and ultimately increase BMI over the lifespan. Early childhood and adolescent adversity can induce long-lasting alterations in the glucocorticoid and dopamine systems that lead to increased addiction vulnerability later in life. Allostatic load, the hypothalamic-pituitary-adrenal axis, and emerging data on epigenetics in the context of biological embedding are highlighted. A conceptual model for food addiction is proposed, which integrates data on the biological embedding of adversity as well as upstream psychological, social, and environmental factors. Dietary restraint as a feature of disordered eating is discussed as an important contextual factor related to food addiction. Discussion of various public health and policy considerations are based on the concept that improved knowledge of biopsychosocial mechanisms contributing to food addiction may decrease stigma associated with obesity and disordered eating behavior.

Climate change is a major stressor causing poor pregnancy outcomes and child development

The climate crisis is the existential threat of our times and for generations to come. This is no longer a threat but a reality affecting us, our children, and the generations that follow. Pregnant mothers, their fetuses, and their children are among those at greatest risk in every population and every jurisdiction. A timely consideration is the health of racialized groups who are particularly vulnerable owing to the confluence of several risk factors that are compounded by climate change. Included among these are Indigenous communities that are the most directly threatened by climate change. This review discusses the main health challenges faced by mothers, fathers, and their children during the climate crisis, focusing on mental health as a causal factor. Exploration of this topic includes the role of prenatal maternal and paternal stresses, allostatic load, and the effect of degradation of the environment and ecosystems on individuals. These will be examined in relation to adverse pregnancy outcomes and altered developmental trajectories of children. The climate crisis is a health threat multiplier that amplifies the health inequities of the most at-risk populations and individuals. It accelerates the increase in allostatic load of those at risk. The path of tragedy begins with an accumulating allostatic load that overwhelms both individual and socio-ecological resilience. This can lead to worse mental health including depression and anxiety and, in the case of pregnant women and their children, more adverse pregnancy outcomes and impaired developmental trajectories for their newborn children. We argue that there is an urgent need to develop new (or re-discover or re-purpose existing) tools that will predict communities and individuals who are experiencing the highest levels of climate-related hazards and intervene to reduce stress and increase resilience in pre-conceptual women and men, pregnant and post-partum women, and their young children.

Implications of early life stress on fetal metabolic programming of schizophrenia: A focus on epiphenomena underlying morbidity and early mortality

The fetal origin of adult disease hypothesis postulates that a stressful in utero environment can have deleterious consequences on fetal programming, potentially leading to chronic disease in later life. Factors known to impact fetal programming include the timing, intensity, duration and nature of the external stressor during pregnancy. As such, dynamic modulation of fetal programming is heavily involved in shaping health throughout the life course, possibly by influencing metabolic parameters including insulin action, hypothalamic-pituitary-adrenal activity and immune function. The ability of prenatal insults to program adult disease is likely to occur as a result of reduced functional capacity in key organs-a "thrifty" phenotype-where more resources are re-allocated to preserve critical organs such as the brain. Notably, it has been postulated that the manifestation of neuropsychiatric disorders in individuals priorly exposed to prenatal stress may arise from the interaction between hereditary factors and the intrauterine environment, which together precipitate disease onset by disrupting the trajectory of normal brain development. In this review we discuss the evidence linking prenatal programming to neuropsychiatric disorders, mainly schizophrenia, via a "Thrifty psychiatric phenotype" concept. We start by outlining the conception of the thrifty psychiatric phenotype. Next, we discuss the convergence of potential mechanistic pathways through which prenatal insults may trigger epigenetic changes that contribute to the increased morbidity and early mortality observed in neuropsychiatric disorders. Finally, we touch on the public health importance of fetal programming for these disorders. We conclude by providing a brief outlook on the future of this evolving field of research.

Prenatal Maternal Objective and Subjective Stress Exposures and Rapid Infant Weight Gain

OBJECTIVES

To evaluate the associations between 3 prenatal stress exposures and rapid infant weight gain.

STUDY DESIGN

Participants were 162 maternal-child dyads drawn from a nonrandomized controlled trial evaluating a prenatal intervention for reducing women's stress and excessive gestational weight gain and subsequent longitudinal observational study of offspring outcomes. Participants were predominantly low-income and racial or ethnic minorities, and mothers were overweight or obese prepregnancy. Primary exposures were objective stress exposures (number of stressful life events) and subjective distress (maternal perceived stress and depressive symptoms) during pregnancy. The primary outcome was rapid infant weight gain from birth to 6 months, assessed via birth records and in-person anthropometry measurements.

RESULTS

In total, 28% of the sample (N = 40) met criteria for rapid infant weight gain. In adjusted models, exposure to prenatal stressful life events was associated with increased odds of rapid infant weight gain (OR 1.40, 95% CI 1.07-1.83, P = .014). Neither prenatal perceived stress (OR 0.47, 95% CI 0.16-1.37, P = .17) nor depressive symptoms (OR 0.89, 95% CI 0.76-1.03, P = .13) were significantly associated with rapid infant weight gain.

CONCLUSIONS

Each additional stressful life event a woman experienced during pregnancy was associated with 40% greater odds of rapid infant weight gain. Future research should evaluate whether prenatal interventions that focus on reducing exposure to stressful events prevent rapid infant weight gain.

Intergenerational transmission of the effects of maternal exposure to childhood maltreatment on offspring obesity risk: A fetal programming perspective

Childhood obesity constitutes a major global public health challenge. A substantial body of evidence suggests that conditions and states experienced by the embryo/fetus in utero can result in structural and functional changes in cells, tissues, organ systems and homeostatic set points related to obesity. Furthermore, growing evidence suggests that maternal conditions and states experienced prior to conception, such as stress, obesity and metabolic dysfunction, may spill over into pregnancy and influence those key aspects of gestational biology that program offspring obesity risk. In this narrative review, we advance a novel hypothesis and life-span framework to propose that maternal exposure to childhood maltreatment may constitute an important and as-yet-underappreciated risk factor implicated in developmental programming of offspring obesity risk via the long-term psychological, biological and behavioral sequelae of childhood maltreatment exposure. In this context, our framework considers the key role of maternal-placental-fetal endocrine, immune and metabolic pathways and also other processes including epigenetics, oocyte mitochondrial biology, and the maternal and infant microbiomes. Finally, our paper discusses future research directions required to elucidate the nature and mechanisms of the intergenerational transmission of the effects of maternal childhood maltreatment on offspring obesity risk.

An Epigenetics-Based, Lifestyle Medicine-Driven Approach to Stress Management for Primary Patient Care: Implications for Medical Education

Over 75% of patients in the primary care setting present with stress-related complaints. Curiously, patients and health care providers all too often see stress as a relatively benign sequela of many common illnesses such as heart disease, cancer, lung disease, dementia, diabetes, and mental illness. Unfortunately, various day-to-day lifestyle choices and environmental factors, unrelated to the presence of any disease, can cause stress sufficient to contribute to the development of various diseases/disorders and suboptimal health. There is evidence suggesting that counseling in stress management-oriented therapeutic interventions (as offered by lifestyle medicine-oriented practitioners) may prevent or reduce the onset, severity, duration, and/or overall burden of stress-related illnesses. Such counseling often involves considerations such as the patient's nutrition, physical activity, interest in/capacity to meditate, drug abuse/cessation, and so on. Unfortunately, lifestyle medicine-oriented approaches to stress management are rarely offered in primary care-the patient care arena wherein such counseling would likely be best received by patients. Would health care outcomes improve if primary care providers offered counseling in both stress management and positive lifestyle choices? The purpose of this article is to provide both primary care practitioners and educators in health care training programs with an introductory overview of epigenetics. An emerging field of science offering insights into how factors such as stress and lifestyle choices interact with our genes in ways that can both positively and negatively impact the various micro (eg, cellular) through macro (eg, physiologic, pathophysiologic) processes that determine our tendencies toward illness or wellness. A deeper understanding of epigenetics, as provided herein, should enable primary care providers and medical educators to more confidently advocate for the primary benefits associated with counseling in both stress reduction and the pursuit of healthy lifestyle choices.

The role of glucocorticoid and mineralocorticoid receptor DNA methylation in antenatal depression and infant stress regulation

Understanding fetal programming pathways that underpin the relationship between maternal and offspring mental health necessitates an exploration of potential role of epigenetic variation in early development. Two genes involved in stress response regulation, the glucocorticoid and mineralocorticoid receptors (NR3C1 and NR3C2) have been a focus in understanding stressful exposures and mental health outcomes. Data were obtained from 236 pregnant women from the Mercy Pregnancy Emotional Wellbeing Study (MPEWS), a selected pregnancy cohort, recruited in early pregnancy. Depression was measured using the Structured Clinical Interview for DSM-IV (SCID-IV) and repeated measures of the Edinburgh Postnatal Depression Scale (EPDS). Antidepressant use, stressful events and anxiety symptoms were measured. NR3C1 and NR3C2 DNA methylation was measured in placental and infant buccal samples. Infant cortisol was measured in repeat saliva samples across a task. This study found maternal early pregnancy depressive disorder and symptoms were associated with lower DNA methylation at NR3C2 CpG_24 in placental tissue. There were no significant differences for depression or antidepressant use for DNA methylation of NR3C1. Antenatal depression was associated with lower infant cortisol reactivity at 12 months. DNA methylation in CpG_24 site in NR3C2 in placental samples suppressed the relationship between early maternal depressive symptoms and infant cortisol reactivity. These findings show a relationship between antenatal depression, NR3C2 DNA methylation and infant cortisol response providing support for a specific fetal programming pathway. Further research is required to examine the stability of this epigenetic mark across childhood and long-term mental health outcomes.

Combined neurodevelopmental exposure to deltamethrin and corticosterone is associated with Nr3c1 hypermethylation in the midbrain of male mice

Attention-Deficit Hyperactivity Disorder (ADHD) is one of the most common neurodevelopmental disorders and manifests inattention, hyperactivity, and impulsivity symptoms in childhood that can last throughout life. Genetic and environmental studies implicate the dopamine system in ADHD pathogenesis. Work from our group and that of others indicates that deltamethrin insecticide and stress exposure during neurodevelopment leads to alterations in dopamine function, and we hypothesized that exposure to both of these factors together would lead to synergistic effects on DNA methylation of key genes within the midbrain, a highly dopaminergic region, that could contribute to these findings. Through targeted next-generation sequencing of a panel of cortisol and dopamine pathway genes, we observed hypermethylation of the glucocorticoid receptor gene, Nr3c1, in the midbrain of C57/BL6N males in response to dual deltamethrin and corticosterone exposures during development. This is the first description of DNA methylation studies of Nr3c1 and key dopaminergic genes within the midbrain in response to a pyrethroid insecticide, corticosterone, and these two exposures together. Our results provide possible connections between environmental exposures that impact the dopamine system and the hypothalamic-pituitary-adrenal axis via changes in DNA methylation and provides new information about the presence of epigenetic effects in adulthood after exposure during neurodevelopment.

Programming effects of maternal stress on the circadian system of adult offspring

Maternal stress has long-lasting influences on the brain functions of offspring, and several brain regions have been proposed to mediate such programming. Although perinatal programming of crosstalk between the circadian and stress systems has been proposed, the functional consequences of prenatal stress on the circadian system and the underlying mechanisms remain largely unknown. Therefore, we investigated whether exposing pregnant mice to chronic restraint stress had prolonged effects on the suprachiasmatic nucleus (SCN), which bears the central pacemaker for mammalian circadian rhythms, of offspring. SCN explants from maternally stressed mice exhibited altered cyclic expression patterns of a luciferase reporter under control of the mouse Per1 promoter (mPer1::LUC), which manifested as a decreased amplitude and impaired stability of the rhythm. Bioluminescence imaging at the single-cell level subsequently revealed that impaired synchrony among individual cells was responsible for the impaired rhythmicity. These intrinsic defects appeared to persist during adulthood. Adult male offspring from stressed mothers showed advanced-phase behavioral rhythms with impaired stability as well as altered clock gene expression in the SCN. In addition to affecting the central rhythm, maternal stress also had prolonged influences on the circadian characteristics of the adrenal gland and liver, as determined by circulating corticosterone levels and hepatic glycogen content, and on canonical clock gene mRNA expression in those tissues. Taken together, our findings suggest that the SCN is a key target of the programming effects of maternal stress. The widespread effects of circadian disruptions caused by a misprogrammed clock may have further impacts on metabolic and mental health in later life.

When pregnant mothers are stressed, the fetus’s circadian rhythms are reprogrammed, increasing the risk of health complications later in life. Stress during pregnancy was known to negatively affect the fetus, but how it affected circadian rhythms (day/night patterns of alertness) was poorly understood. Kyungjin Kim (Daegu Gyeongbuk Institute of Science and Technology) and Sooyoung Chung (Ewha Womans University, Seoul), both in South Korea, and co-workers stressed pregnant mice by confining them in small tubes, then measured the effects on their offspring. Pups of stressed mothers showed disturbed circadian rhythms, and the effects persisted into adulthood. Further analysis showed that the rhythms were disrupted because individual cells in the key brain region regulating circadian rhythms were poorly synchronized. These results suggest potential treatments to counteract the negative effects of prenatal stress on circadian rhythms.

Anxiety among women experiencing medically complicated pregnancy: A systematic review and meta-analysis

BACKGROUND

Symptoms of anxiety are common among pregnant and postpartum women, and 15%-20% of pregnancies are affected by medical complications. Despite this, little is known about the relationship of medical complications in pregnancy and women's experience of anxiety. The purpose of this research was to conduct a systematic review and meta-analysis of differences in anxiety symptom severity among women experiencing a medically complicated versus a medically uncomplicated pregnancy.

METHODS

This work was guided by the PRISMA reporting process. Electronic databases MEDLINE and PsycINFO were searched to identify studies that met the inclusion criteria. An adaptation of the Newcastle-Ottawa Quality Assessment Scale for case-control studies was used to perform a quality assessment review. A random-effects meta-analysis was used to calculate the estimated average standardized mean differences.

RESULTS

Based on the five studies which met our inclusion criteria, findings provide evidence of higher levels of anxiety symptoms among pregnant women experiencing a medically complicated versus a medically uncomplicated pregnancy. Despite considerable heterogeneity, all mean difference estimates are in the direction of greater anxiety in the high-risk groups.

CONCLUSIONS

Women experiencing a medically complex pregnancy report higher levels of anxiety symptoms compared to women experiencing a medically uncomplicated pregnancy.

Epigenetic Biomarkers for Environmental Exposures and Personalized Breast Cancer Prevention

Environmental and lifestyle factors are believed to account for >80% of breast cancers; however, it is not well understood how and when these factors affect risk and which exposed individuals will actually develop the disease. While alcohol consumption, obesity, and hormone therapy are some known risk factors for breast cancer, other exposures associated with breast cancer risk have not yet been identified or well characterized. In this paper, it is proposed that the identification of blood epigenetic markers for personal, in utero, and ancestral environmental exposures can help researchers better understand known and potential relationships between exposures and breast cancer risk and may enable personalized prevention strategies.

Prenatal two-hit stress affects maternal and offspring pregnancy outcomes and uterine gene expression in rats: match or mismatch?

Maternal stress and inflammation excesses can lead to adverse pregnancy outcomes and offspring development. We evaluated whether distinct prenatal stressors affect pregnancy, maternal and offspring outcomes, and uterine gene expression differently when combined than either alone. Long-Evans dams were exposed to psychological or/and (two-hit) immune stress (interleukin-1 beta [IL-1β]), on gestational days 12-18 and 17-delivery, respectively. Gestational length, maternal weight gain, glycaemia and corticosterone levels, offspring weight, and gender effects were recorded. Maternal and offspring uteri were collected at weaning and on postnatal day 160 correspondingly. Uterine expression of genes involved in local progesterone metabolism, neuroendocrine and immune systems were analyzed using quantitative real-time polymerase chain reaction. Maternal two-hit stress increased gestational length variation and the occurrence of adverse pregnancy outcomes while reducing gestational weight gain. Pup weight was negatively affected by prenatal stressors in a gender-specific way. In dams, IL-1β upregulated gene expression of neuroendocrine (Crh, Crhr1) and cytokine genes (Il1b, Il1rn, Il6, and Il10). Conversely, transcriptional patterns in offspring uteri were more variable with gene-specific up- or downregulation by each stressor separately, while exposure to both extensively reduced the expression of neuroendocrine (Hsd11b1), cytokine (Il1a, Il1rn, Il6), and IL-1 receptor genes. In conclusion, maternal stress affects physiological and molecular processes in dams and their offspring; two hits have different effects than single stressors. Outcomes appear generation-, gender-, and stressor-specific. Dampening of offspring uterine gene expression after exposure to multiple stressors could fit within the match/mismatch hypothesis of perinatal programming, with offspring preparing for a stressful life.

Moderate prenatal stress may buffer the impact of Superstorm Sandy on placental genes: Stress in Pregnancy (SIP) Study

The placenta plays a central role in the epigenetic programming of neurodevelopment by prenatal stress (PS), but this pathway is not fully understood. It difficult to study in humans because the conditions for intense, traumatic PS are almost impossible to create ethically. This study was able to capitalize on a 2012 disaster that hit New York, Superstorm Sandy, to examine the impact of traumatic stress on placental gene expression while also examining normative PS, and compare the two. Of the 303 expectant mothers participating in the Stress in Pregnancy Study, 95 women were pregnant when Superstorm Sandy struck. During their pregnancy, participants completed self-report measures of PS and distress that were combined, using latent profile analysis, into one global indicator of normative PS. Placental tissue was collected at delivery and frozen for storage. RNA expression was assessed for 40 placental genes known to associate with the stress response system and neurodevelopment in offspring. Results showed that normative PS increased expression of just MECP2, HSD11B2, and ZNF507, whereas Superstorm Sandy PS decreased expression of CDKL5, CFL1, DYRK1A, HSD11B2, MAOA, MAOB, NCOR1, and ZNF507. Interaction analyses indicated that Superstorm Sandy PS was associated with decreased gene expression for the low and high PS group for CFL1, DYRK1A, HSD11B2, MAOA, and NCOR1 and increased expression for the moderate PS group for FOXP1, NR3C1, and NR3C2. This study supports the idea that a moderate amount of normative PS may buffer the impact of traumatic PS, in this case caused by Superstorm Sandy, on placental gene expression, which suggests that the placenta itself mirrors the organism's ability to develop an epigenetic resilience to, and inoculation from, stress.

Preterm birth is associated with epigenetic programming of transgenerational hypertension in mice

Renal and cardiovascular complications of prematurity are well established, notably the development of hypertension in adulthood. However, the underlying molecular mechanisms remain poorly understood. Our objective was to investigate the impact of prematurity on the ontogenesis of renal corticosteroid pathways, to evaluate its implication in perinatal renal complications and in the emergence of hypertension in adulthood. Swiss CD1 pregnant mice were injected with lipopolysaccharides at 18 days of gestation (E18) to induce prematurity at E18.5. Pups were sacrificed at birth, 7 days and 6 months of life. Second (F2) and third (F3) generations, established by mating prematurely born adult females with wild-type males, were also analyzed. Former preterm males developed hypertension at M6 (P < 0.0001). We found robust activation of renal corticosteroid target gene transcription at birth in preterm mice (αENaC (+45%), Gilz (+85%)), independent of any change in mineralocorticoid or glucocorticoid receptor expression. The offspring of the preterm group displayed increased blood pressure in F2 and F3, associated with increased renal Gilz mRNA expression, despite similar MR or GR expression and plasma corticosteroid levels measured by LC-MS/MS. Gilz promoter methylation measured by methylated DNA immunoprecipitation-qPCR was reduced with a negative correlation between methylation and expression (P = 0.0106). Our study demonstrates prematurity-related alterations in renal corticosteroid signaling pathways, with transgenerational inheritance of blood pressure dysregulation and epigenetic Gilz regulation up to the third generation. This study provides a better understanding of the molecular mechanisms involved in essential hypertension, which could partly be due to perinatal epigenetic programming from previous generations.

A propensity towards high blood pressure may be passed down through several generations from adults who were born preterm. People who are born prematurely often suffer from kidney (renal) problems, high blood pressure and cardiovascular disease as they age. Recent research suggests adults born prematurely can pass dysregulated blood pressure to their children. Laetitia Martinerie at INSERM Unit 1185, Le Kremlin Bicêtre and Robert Debré Hospital in Paris, France, and co-workers studied generations of mice to explore how epigenetic alterations, DNA modifications that do not change the DNA code, affect blood pressure from birth through to adulthood. The team identified tissue-specific alterations in renal signaling pathways in premature mice. They also traced the associated overexpression of a gene called Gilz, known to play a role in blood pressure maintenance, through second and third generation mice born to the first generation preterms.

Epigenome-wide association study of depression symptomatology in elderly monozygotic twins

Depression is a severe and debilitating mental disorder diagnosed by evaluation of affective, cognitive and physical depression symptoms. Severity of these symptoms strongly impacts individual's quality of life and is influenced by a combination of genetic and environmental factors. One of the molecular mechanisms allowing for an interplay between these factors is DNA methylation, an epigenetic modification playing a pivotal role in regulation of brain functioning across lifespan. The aim of this study was to investigate if there are DNA methylation signatures associated with depression symptomatology in order to identify molecular mechanisms contributing to pathophysiology of depression. We performed an epigenome-wide association study (EWAS) of continuous depression symptomatology score measured in a cohort of 724 monozygotic Danish twins (346 males, 378 females). Through EWAS analyses adjusted for sex, age, flow-cytometry based blood cell composition, and twin relatedness structure in the data we identified depression symptomatology score to be associated with blood DNA methylation levels in promoter regions of neuropsin (KLK8, p-value = 4.7 × 10^-7) and DAZ associated protein 2 (DAZAP2, p-value = 3.13 × 10^-8) genes. Other top associated probes were located in gene bodies of MAD1L1 (p-value = 5.16 × 10^-6), SLC29A2 (p-value = 6.15 × 10^-6) and AKT1 (p-value = 4.47 × 10^-6), all genes associated before with development of depression. Additionally, the following three measures (a) DNAmAge (calculated with Horvath and Hannum epigenetic clock estimators) adjusted for chronological age, (b) difference between DNAmAge and chronological age, and (c) DNAmAge acceleration were not associated with depression symptomatology score in our cohort. In conclusion, our data suggests that depression symptomatology score is associated with DNA methylation levels of genes implicated in response to stress, depressive-like behaviors, and recurrent depression in patients, but not with global DNA methylation changes across the genome.

Maternal antenatal daytime sleepiness and child neuropsychiatric and neurocognitive development

BACKGROUND

The prevalence of sleep problems among pregnant women is over 50%, and daytime sleepiness is among the most common sleep problems. Previous studies have associated antenatal sleep problems with adverse maternal health and neonatal outcomes, but the consequences of antenatal sleep problems and particularly daytime sleepiness on child psychological development have not been assessed prospectively.

METHODS

In this prospective cohort study including 111 mother-child dyads, we examined the associations of maternal daytime sleepiness during pregnancy, assessed at 17 and 28 weeks of gestation using the Epworth Sleepiness Scale, with child neuropsychiatric problems and neuropsychological development, assessed with mother-rated questionnaires and individually administered neuropsychological tests, at child age 2.6-5.7 years (mean = 4.3 years).

RESULTS

Independently of sociodemographic and perinatal covariates and maternal depressive and anxiety symptoms during and/or after pregnancy, maternal antenatal daytime sleepiness was associated with increased total [unstandardized regression coefficient (B) = 0.25 standard deviation (s.d.) units; 95% confidence interval (CI) 0.01-0.48] and internalizing (B = 0.25 s.d.s: 95% CI 0.01-0.49) psychiatric problems and ADHD symptoms (B = 0.27 s.d.s: 95% CI 0.04-0.50) in children, and with poorer executive function, particularly in the areas of attention, working memory and inhibitory control (B = -0.39 s.d.s: 95% CI -0.69 to -0.10).

CONCLUSIONS

Maternal antenatal daytime sleepiness carries adverse consequences for offspring psychological development. The assessment of sleep problems may be an important addition to standard antenatal care.

Mismatched Prenatal and Postnatal Maternal Depressive Symptoms and Child Behaviours: A Sex-Dependent Role for NR3C1 DNA Methylation in the Wirral Child Health and Development Study

Evolutionary hypotheses predict that male fetuses are more vulnerable to poor maternal conditions (Sex-biased Maternal Investment), but female fetuses are at greater risk of glucocorticoid-mediated disorders where there is a mismatch between fetal and postnatal environments (Predictive Adaptive Response). Self-reported prenatal and postnatal depression and maternal report of child anxious-depressed symptoms at 2.5, 3.5 and 5.0 years were obtained from an ‘extensive’ sample of first-time mothers (N = 794). Salivary NR3C1 1-F promoter methylation was assayed at 14 months in an ‘intensive’ subsample (n = 176) and stratified by psychosocial risk. Generalised structural equation models were fitted and estimated by maximum likelihood to allow the inclusion of participants from both intensive and extensive samples. Postnatal depression was associated with NR3C1 methylation and anxious-depressed symptoms in daughters of mothers with low prenatal depression (prenatal-postnatal depression interaction for methylation, p < 0.001; for child symptoms, p = 0.011). In girls, NR3C1 methylation mediated the association between maternal depression and child anxious-depressed symptoms. The effects were greater in girls than boys: the test of sex differences in the effect of the prenatal-postnatal depression interaction on both outcomes gave X² (2) = 5.95 (p = 0.051). This was the first human study to show that epigenetic and early behavioural outcomes may arise through different mechanisms in males and females.

Maternal hair cortisol levels as a novel predictor of neonatal abstinence syndrome severity: A pilot feasibility study

Neonatal abstinence syndrome (NAS) after in-utero opioid exposure remains a poorly understood condition with multiple factors contributing to severity. Exposure to maternal stress may be one contributing factor. Hair cortisol measurement represents a novel technique for assessing prenatal stress. In this pilot study, the association between maternal hair cortisol levels and NAS severity was examined in 70 postpartum women with opioid use disorder within 72 hr of delivery. Infants were monitored for NAS and treated according to institutional protocol. Forty-four (63%) of the infants were pharmacologically treated for NAS, with a mean length of hospital stay (LOS) for all infants of 14.2 (SD 9.0) days. The mean cortisol level in the mothers was 131.8 pg/mg (SD 124.7). In bivariate analysis, higher maternal hair cortisol levels were associated with shorter infant LOS (R = -.26, p = .03) and fewer infant opioid treatment days (R = -.28, p = .02). Results were no longer statistically significant in regression models after adjusting for maternal opioid and smoking. In conclusion, we demonstrated the feasibility of hair cortisol assaying within the first few days after delivery in mothers with opioid use disorder as a novel marker for NAS. The findings suggest that maternal stress may impact the severity of infant opioid withdrawal.

Translating basic research knowledge on the biological embedding of early-life stress into novel approaches for the developmental programming of lifelong health

This review integrates scientific knowledge obtained over the past few decades on the biological mechanisms that contribute to the profound association between exposure to early adversity, including childhood trauma and prenatal stress, and the lifelong elevated risk to develop a broad range of diseases. We further discuss insights into gene-environment interactions moderating the association between early adversity and disease manifestation and we discuss the role of epigenetic and other molecular processes in the biological embedding of early adversity. Based on these findings, we propose potential mechanisms that may contribute to the intergenerational transmission of risk related to early adversity from the mother to the fetus. Finally, we argue that basic research knowledge on the biological embedding of early adversity must now be translated into novel intervention strategies that are mechanism-driven and sensitive to developmental timing. Indeed, to date, there are no diagnostic biomarkers of risk or mechanism-informed interventions that we can offer to victims of early adversity in order to efficiently prevent or reverse adverse health outcomes. Such translational efforts can be expected to have significant impact on both clinical practice and the public health system, and will promote precision medicine in pediatrics and across the lifespan.

Programming Effects of Prenatal Stress on Neurodevelopment-The Pitfall of Introducing a Self-Fulfilling Prophecy

There is increasing interest for the potential harmful effects of prenatal stress on the developing fetal brain, both in scientific literature and in public press. Results from animal studies suggest that gestational stress leads to an altered offspring neurodevelopment with adverse behavioral and cognitive consequences. Furthermore, there are indications in human studies that severe prenatal stress has negative consequences for the child's neurodevelopment. However, stress is an umbrella term and studies of maternal stress have focused on a wide range of stress inducing situations, ranging from daily hassles to traumatic stress after bereavement or a natural disaster. Mild to moderate stress, experienced by many women during their pregnancy, has not consistently been shown to exert substantial negative effects on the child's neurodevelopment. Additionally, the vast majority of human studies are observational cohort studies that are hampered by their fundamental inability to show a causal relationship. Furthermore, our limited knowledge on the possible underlying mechanisms and the effects of interventions for prenatal stress on child neurodevelopmental outcomes emphasize our incomplete understanding of the actual effects of prenatal stress on child neurodevelopment. Until we have a better understanding, it seems counterproductive to alarm all pregnant women for possible harmful effects of all sorts of prenatal stress, if only to avoid the induction of stress itself.