Disruption of fetal hormonal programming (prenatal stress) implicates shared risk for sex differences in depression and cardiovascular disease

Skeletal and Adipose Manifestations of Stress in a Contemporary Pediatric Sample

INTRODUCTION

Adverse experiences leading to physiological disruptions (stress) in early life produce cascade effects on various biological systems, including the endocrine and metabolic systems, which, in turn, shape the developing skeletal system. To evaluate the effects of stress on adipose and skeletal tissues, we examine the relationship between skeletal indicators of stress (porotic hyperostosis [PH] and cribra orbitalia [CO]), bone mineral density (BMD), vertebral neural canal (VNC) diameters, and adipose tissue distribution in a contemporary pediatric autopsy sample.

METHODS

Data is from 702 (409 males, 293 females) individuals from a pediatric (0.5-20.9 years) autopsy sample from New Mexico who died between 2011 and 2022. Data includes visceral adipose tissue (VAT) in the abdomen, heart, and liver, CO/PH, VNC size of the fifth lumbar vertebra, and BMD.

RESULTS

We find that adipose tissue distribution and location are differentially associated with CO/PH, BMD, and VNC size; VNC size is smaller, and liver adiposity is higher in those with CO/PH. Further, increased VAT and small VNC size are associated with PH presence and low BMD. Body mass index categories do not correspond with porous cranial lesion presence.

CONCLUSIONS

This paper provides evidence for the complex relationship between skeletal markers of early-life stress (CO/PH, reduced VNC size, low BMD) and endocrine system function. VAT distribution and VNC size are partly shaped by stressors during gestation, likely through alterations of the HPA axis. It is possible that alterations of the HPA axis due to gestational stress also shape the expression of porous cranial lesions during exposure to childhood stressors.

Maternal immune activation by toll-like receptor 7 agonist during mid-gestation increases susceptibility to blood-brain barrier leakage after puberty

Maternal immune activation (MIA), a maternal stressor, increases risk for neuropsychiatric diseases, such as Major Depressive Disorder in offspring. MIA of toll-like receptor 7 (TLR7) initiates an immune response in mother and fetuses in a sex-selective manner. The paraventricular nucleus of the hypothalamus (PVN), a brain region that is sexually dimorphic and regulates hypothalamic-pituitary-adrenal (HPA) stress responses, have been tied to stress-related behaviors (i.e., depression, anxiety, social impairments). The current study characterized the sex-selective impact of mid-gestational TLR7 activation on PVN vasculature of adult offspring based on a prior study of excess prenatal glucocorticoid stress. The PVN of offspring were evaluated to determine if fetal MIA impacted vascular leakage in the brains of adult mice with or without restraint stress. Timed-pregnant female mice were administered the TLR7 agonist Resiquimod (RQ) or saline vehicle on embryonic day (E) 12.5. Basal and restraint stress-induced corticosterone was measured to examine changes in stress response. Mice were perfused transcardially with fluorescein isothiocyanate (FITC) to assess blood vessel integrity. Sections with FITC-labeled blood vessels through the PVN of offspring were immunolabeled for Glial Fibrillary Acidic Protein (GFAP; astrocytic end feet) and IBA-1 (microglia). MIA with RQ led to elevated levels of plasma corticosterone 60-minutes after restraint in offspring, suggesting prenatal RQ impairs glucocorticoid negative feedback. Blood-brain barrier integrity was assessed. Adult offspring of RQ injected dams showed greater leakage in the PVN (greater in males than females). GFAP+ colocalization with FITC-labeled vessels was lower in the PVN of offspring from RQ treated dams, potentially contributing to the observed increased FITC leakage. Microglia were examined in relation to the vasculature as an indicator of a neuroimmune response. Data show IBA-1+ cells greater in size and number in the PVN with closer proximity to blood vessels after maternal injection of RQ in a male-selective manner. Microglia were unchanged in females from RQ-treated dams but were smaller in size after restraint. This study provides support for sex-selective influences of fetal immune antecedents for altered brain vascular and blood brain barrier development and adult neuroendocrine function that could indicate a PVN locus for increased susceptibility for adult disorders.

Age- and sex-dependent cardiovascular impact of maternal perinatal stress and altered dopaminergic metabolism in the medulla oblongata of the offspring

Maternal major depressive disorder with peripartum onset presents health risks to the mother and the developing fetus. Using a rat model of chronic mild stress, we previously reported on the neurodevelopmental impact of maternal perinatal stress on their offspring. This study examined the cardiovascular impact of maternal perinatal stress on their offspring. The cardiovascular impact was assessed in terms of blood pressure and echocardiographic parameters. The results examined by a three-way ANOVA showed a significant association of cardiovascular parameters with maternal perinatal stress and offspring sex and age. Increased blood pressure was observed in adolescent female and adult male offspring of stress-exposed dams. Echocardiography showed an increase in left atrial dimension and a reduction in left ventricular systolic function in adolescent stress-exposed female offspring. Increased interventricular septum thickness at end-diastole and left ventricular diastolic dysfunction were observed in adult stress-exposed male offspring. The underlying mechanisms of cardiovascular impact were examined in stress-exposed adult offspring by assessing the levels of neurotransmitters and their metabolites in the medulla oblongata using high-performance liquid chromatography. A significant decrease in homovanillic acid, a dopamine metabolite and indicator of dopaminergic activity, was observed in adult stress-exposed female offspring. These results suggest a significant sex- and age-dependent impact of maternal stress during the peripartum period on the cardiovascular system in the offspring that extends to adulthood and suggests a multigenerational effect. The presented data urgently need follow-up to confirm their potential clinical and public health relevance.NEW & NOTEWORTHY We demonstrate that maternal perinatal stress is associated with sex- and age-dependent impact on the cardiovascular system in their offspring. The effect was most significant in adolescent female and adult male offspring. Observed changes in hemodynamic parameters and dopaminergic activity of the medulla oblongata are novel results relevant to understanding the cardiovascular impact of maternal perinatal stress on the offspring. The cardiovascular changes observed in adult offspring suggest a potential long-term, multigenerational impact of maternal perinatal stress.

Maternal immune activation with toll-like receptor 7 agonist during mid-gestation alters juvenile and adult developmental milestones and behavior

Infections during pregnancy are associated with increased risk for adult neuropsychiatric disease, such as major depressive disorder, schizophrenia, and autism spectrum disorder. In mouse models of maternal immune activation (MIA), different toll-like receptors (TLRs) are stimulated to initiate inflammatory responses in mother and fetus. The goal of this study was to determine sex-dependent aspects of MIA using a TLR7/8 agonist, Resiquimod (RQ), on neurodevelopment. RQ was administered to timed-pregnant mice on embryonic day (E) 12.5. At E15, maternal/fetal plasma cytokines were measured by enzyme-linked immunosorbent assay (ELISA). Maternal cytokines interleukin (IL)-6 and IL-10 were higher while tumor necrosis factor (TNF)-α and IL-17 were lower in pregnant dams exposed to RQ. Fetal cytokines (E15) were altered at the same timepoint with fetal plasma IL-6 and IL-17 greater after RQ compared to vehicle, while IL-10 and TNF-α were higher in male fetuses but not female. Other timed-pregnant dams were allowed to give birth. MIA with RQ did not alter the female to male ratio of offspring born per litter. Body weights were reduced significantly in both sexes at birth, and over the next 5 weeks. Offspring from RQ-injected mothers opened their eyes 5 days later than controls. Similarly, female offspring from RQ-injected mothers exhibited pubertal delay based on vaginal opening 2-3 days later than control females. On the behavioral side, juvenile and adult male and female MIA offspring exhibited less social-like behavior in a social interaction test. Anhedonia-like behavior was greater in MIA adult female mice. This study provides support for sex-dependent influences of fetal antecedents for altered brain development and behavioral outputs that could be indicative of increased susceptibility for adult disorders through immune mechanisms. Future studies are needed to determine neural cellular and molecular mechanisms for such programming effects.

Mental illness and cardiovascular health: observational and polygenic score analyses in a population-based cohort study

BACKGROUND

Individuals with serious mental illness have a markedly shorter life expectancy. A major contributor to premature death is cardiovascular disease (CVD). We investigated associations of (genetic liability for) depressive disorder, bipolar disorder and schizophrenia with a range of CVD traits and examined to what degree these were driven by important confounders.

METHODS

We included participants of the Dutch Lifelines cohort (N = 147 337) with information on self-reported lifetime diagnosis of depressive disorder, bipolar disorder, or schizophrenia and CVD traits. Employing linear mixed-effects models, we examined associations between mental illness diagnoses and CVD, correcting for psychotropic medication, demographic and lifestyle factors. In a subsample (N = 73 965), we repeated these analyses using polygenic scores (PGSs) for the three mental illnesses.

RESULTS

There was strong evidence that depressive disorder diagnosis is associated with increased arrhythmia and atherosclerosis risk and lower heart rate variability, even after confounder adjustment. Positive associations were also found for the depression PGSs with arrhythmia and atherosclerosis. Bipolar disorder was associated with a higher risk of nearly all CVD traits, though most diminished after adjustment. The bipolar disorder PGSs did not show any associations. While the schizophrenia PGSs was associated with increased arrhythmia risk and lower heart rate variability, schizophrenia diagnosis was not. All mental illness diagnoses were associated with lower blood pressure and a lower risk of hypertension.

CONCLUSIONS

Our study shows widespread associations of (genetic liability to) mental illness (primarily depressive disorder) with CVD, even after confounder adjustment. Future research should focus on clarifying potential causal pathways between mental illness and CVD.

Evaluating different models of maternal stress on stress-responsive systems in prepubertal mice

Introduction

Maternal adversity during pregnancy influences neurodevelopment in human and model animal offspring. Adversity can result from stressors coming from many different directions ranging from environmental to nutritional and physiological to immune (e.g., infection). Most stressors result in fetal overexposure to glucocorticoids that have been directly linked to long- and short-term negative impacts on neurological health of offspring. Neuropsychiatric diseases postulated to have fetal origins are diverse and include such things cardiovascular disease, obesity, affective disorders, and metabolic and immune disorders.

Methods

The experiments in the current study compare 3 stressors: prenatal exposure to dexamethasone (DEX), maternal high fat diet (HFD), and maternal caloric restriction (CR). Offspring of mothers with these treatments were examined prepubertally to evaluate stress responsiveness and stress-related behaviors in in male and female mice.

Results

Prenatal exposure to synthetic glucocorticoid, DEX, resulted in decreased neonatal body weights, reduced social interaction behavior, and hypoactive stress response offspring exposed to maternal DEX. Maternal CR resulted in decreased body weights and social interaction behavior in males and females and increased anxiety-like behavior and acute stress response only in males. HFD resulted in altered body weight gain in both sex offspring with decreased anxiety-like behavior in a female-biased manner.

Discussion

The idea that glucocorticoid responses to different stressors might serve as a common stimulus across stress paradigms is insufficient, given that different modes of prenatal stress produced differential effects. Opposite nutritional stressors produced similar outcomes for anxiety-like behavior in both sexes, social-like behavior in females, and a hyperactive adrenal stress response in males. One common theme among the three models of maternal stress (DEX, CR, and HFD) was consistent data showing their role in activating the maternal and fetal immune response. By tuning in on the more immediate immunological aspect on the developing fetus (e.g., hormones, cytokines), additional studies may tease out more direct outcomes of maternal stress in rodents and increase their translational value to human studies.

Maternal Prenatal Depressive Symptoms and Fetal Growth During the Critical Rapid Growth Stage

Importance

Fetal growth in the critical rapid growth stage (CRGS) before delivery, approximately between 30 to 37 gestational weeks, carries significant implications for subsequent overweight, obesity, and arterial health. Previous evidence has demonstrated the association between maternal depressive symptoms and fetal growth trajectories from early to late pregnancy, but there remains limited understanding of the association of these symptoms with the longitudinal fetal growth change within the CRGS.

Objective

To investigate the association between maternal depressive symptoms and fetal growth during the CRGS before delivery.

Design, Setting, and Participants

This prospective birth cohort study was conducted from January 2018 to December 2020. Volunteer pregnant women were enrolled in their first trimester of prenatal visits. Women with severe disease before pregnancy and multiple births, fetuses with congenital anomalies, and preterm or postterm births were excluded. This multicenter study was based in 13 hospitals covering 81 counties across 12 cities in Sichuan Province, China. Follow-up visits were performed at the second trimester, the third trimester, and 24 hours after delivery. The analysis was conducted from January to May 2023.

Exposures

Maternal depressive symptoms, as a continuous variable, measured by the Edinburgh Postpartum Depression Scale (EPDS) at a median gestational week of 24 (range, 14 to 27) weeks of gestation. A higher score on the EPDS indicates worse depressive symptoms.

Main Outcomes and Measures

The main outcomes included ultrasonography-measured biparietal diameter (BPD), femur length (FL), and abdominal circumference (AC), along with calculated estimated fetal weight (EFW). These parameters were evaluated longitudinally at a median gestational week of 30 (range, 28 to 32) and 37 (range, 35 to 39) weeks. Linear mixed models were used to estimate the associations between maternal depressive symptoms and fetal growth parameters.

Results

A total of 2676 mother-offspring dyads were included, in which the mean (SD) age of mothers was 28.0 (4.4) years, and 1294 (48.4%) of the offspring were female. The median (IQR) maternal EPDS score was 5.0 (4.0 to 9.0). After adjustment for confounders, a significant correlation was found between a higher score of depressive symptoms in mothers and a slower rate of fetal growth across FL (β = -0.40; 95% CI, -0.58 to -0.22), AC (β = -1.97; 95% CI, -2.90 to -1.03), and EFW (β = -50.11; 95% CI, -68.46 to -31.75). These associations were stronger in female fetuses or those with better family socioeconomic conditions.

Conclusions and Relevance

In this prospective cohort study, maternal depressive symptoms were associated with slower fetal growth rate in the CRGS before delivery. Early screening for depressive disorders in pregnant women appears to be essential for fetal growth and later health.

Associations of maternal gestational diabetes mellitus with alterations in cardiovascular system in early childhood

AIMS

The association of maternal gestational diabetes mellitus (GDM) with childhood cardiovascular alterations is not well established. This study aims to test the hypothesis that prenatal exposure to GDM is associated with vascular and cardiac alterations in early childhood.

METHODS

In a population-based prospective cohort among 1094 mothers and their offspring, GDM was diagnosed according to the International Association of Diabetes and Pregnancy Study Groups criteria. Childhood blood pressure (BP) measurement, echocardiography and vascular ultrasound were performed using standardised methods at 4 years old. The associations between maternal GDM and childhood cardiovascular outcomes were modelled using linear regression and binary logistic regression. Mediation analysis was conducted to test the potential mediators.

RESULTS

Maternal GDM was associated with higher systolic BP (SBP; β, 1.20; [0.11, 2.28]), lower left ventricular end-diastolic diameter (LVEDD; β, -0.36; [-0.71, -0.01]), lower end-diastolic volume (EDV; β, -1.42; [-2.71, -0.13]) and increased risk of high blood pressure (HBP, OR = 1.522; 95% CI, 1.023 to 2.264) in offspring at the age of 4 years. After stratification by sex, the association remained strong only in male offspring (SBP: β, 1.94; [0.37, 3.51]; LVEDD: β, -0.60; [-1.09, -0.12]; EDV: β, -2.09; [-3.86, -0.31]; HBP: OR = 1.797; 95% CI, 1.063 to 3.037) and was independent of maternal and child characteristics. However, carotid intima-media thickness (cIMT) was not associated with maternal GDM. Mediation analysis showed that the effects on childhood cardiovascular alterations were attributable mostly to the direct effects of maternal GDM.

CONCLUSIONS

Our results provide evidence that maternal GDM is associated with offspring cardiovascular adaptations at preschool age. Further studies are needed to replicate our results and the long-term effect of these adaptations on later cardiovascular risks needs further investigation.

Estrogen normalizes maternal HFD-induced vascular dysfunction in offspring by regulating ATR

Previous studies have shown that female offspring are resistant to fetal high-fat diet (HFD)-induced programming of heightened vascular contraction; however, the underlying mechanisms remain unclear. The present study tested the hypothesis that estrogen plays a key role in protecting females from fetal programming of increased vascular contraction induced by maternal HFD exposure. Pregnant rats were fed a normal diet (ND) or HFD (60% kcal from fat). Ovariectomy (OVX) and 17β-estradiol (E₂) replacement were performed on 8-week-old female offspring. Aortas were isolated from adult female offspring. Maternal HFD exposure increased angiotensin II (Ang II)-induced contractions of the aorta in adult OVX offspring, which was abrogated by E₂ replacement. The AT₁ receptor (AT₁R) antagonist losartan (10 μM), but not the AT₂ receptor (AT₂R) antagonist PD123319 (10 μM), completely blocked Ang II-induced contractions in both ND and HFD offspring. In addition, HFD exposure caused a decrease in endothelium-dependent relaxations induced by acetylcholine (ACh) in adult OVX but not OVX-E₂ offspring. However, it had no effect on sodium nitroprusside (SNP)-induced endothelium-independent aorta relaxation in any of the six groups. Maternal HFD feeding increased AT₁R, but not AT₂R, leading to an increased AT₁R/AT₂R ratio in HFD-exposed OVX offspring, associated with selective decreases in DNA methylation at the AT_1aR promoter, which was ameliorated by E₂ replacement. Our results indicated that estrogen play a key role in sex differences of maternal HFD-induced vascular dysfunction and development of hypertensive phenotype in adulthood by differently regulating vascular AT₁R and AT₂R gene expression through a DNA methylation mechanism.

Research Centers Collaborative Network Workshop on Sex and Gender Differences in Aging

Aging affects men and women differently; however, the impact of sex and gender on the aging process is not well understood. Moreover, these 2 concepts are often conflated, which further contributes to a lack of clarity on this important issue. In an effort to better understand the relevance of sex and gender in aging research, the Research Centers Collaborative Network sponsored a 1.5-day conference on sex and gender differences in aging that brought together key thought leaders from the 6 National Institute on Aging center programs. The meeting included sessions on comparing males and females, pathophysiological differences, sex/gender in clinical care, and gender and health in the social context. Presenters from a wide array of disciplines identified opportunities for multidisciplinary research to address current gaps in the field and highlighted the need for a more systematic approach to understanding the how and why of sex/gender differences, as well as the health implications of these differences and the sex/gender biases that affect clinical treatment and outcomes. This article summarizes the proceedings of the workshop and provides several recommendations to move the field forward, such as better data collection tools to assess the intersection of sex and gender in epidemiological research; a life course perspective with attention to fetal/developmental origins and key life stages; innovative animal models to distinguish contributions from sex hormones versus sex chromosomes; and integration of sex/gender into teaching and clinical practice. Ultimately, successful implementation of these recommendations will require thoughtful investigations across the translational spectrum and increased collaborations among those with expertise in sex and gender differences.

It's time for sex in cognitive neuroscience

In a discussion paper published in the special issue of Cognitive Neuroscience, Sex Differences in the Brain, we investigated whether certain experimental parameters contributed to findings in functional magnetic resonance imaging studies of sex differences during long-term memory. Experimental parameters included: the number of participants, stimulus type(s), whether or not performance was matched, whether or not sex differences were reported, the type of between-subject statistical test used, and the contrast(s) employed. None of these parameters determined whether or not differences were observed, as all included studies reported sex differences. We also conducted a meta-analysis to determine if there were any brain regions consistently activated to a greater degree in either sex. The meta-analysis identified sex differences (male > female) in the lateral prefrontal cortex, visual processing regions, parahippocampal cortex, and the cerebellum. We received eight commentaries in response to that paper. Commentaries called for an expanded discussion on various topics including the influence of sex hormones, the role of gender (and other social factors), the pros and cons of equating behavioral performance between the sexes, and interpreting group differences in patterns of brain activity. There were some common statistical assumptions discussed in the commentaries regarding the 'file drawer' issue (i.e., the lack of reporting of null results) and effect size. The current paper provides further discussion of the various topics brought up in the commentaries and addresses some statistical misconceptions in the field. Overall, the commentaries echoed a resounding call to include sex as a factor in cognitive neuroscience studies.

Respiratory-gated auricular vagal afferent nerve stimulation (RAVANS) modulates brain response to stress in major depression

BACKGROUND

Negative stress significantly impacts major depressive disorder (MDD), given the shared brain circuitry between the stress response and mood. Thus, interventions that target this circuitry will have an important impact on MDD. The aim of this study was to evaluate the acute effects of a novel respiratory-gated auricular vagal afferent nerve stimulation (RAVANS) technique in the modulation of brain activity and connectivity in women with MDD in response to negative stressful stimuli.

METHODS

Twenty premenopausal women with recurrent MDD in an active episode were included in a cross-over experimental study that included two functional MRI visits within one week, randomized to receive exhalatory- (e-RAVANS) or inhalatory-gated (i-RAVANS) at each visit. Subjects were exposed to a visual stress challenge that preceded and followed RAVANS. A Factorial analysis was used to evaluate the effects of RAVANS on brain activity and connectivity and changes in depressive and anxiety symptomatology post-stress.

RESULTS

Compared with i-RAVANS, e-RAVANS was significantly associated with increased activation of subgenual anterior cingulate, orbitofrontal and ventromedial prefrontal cortices and increased connectivity between hypothalamus and dorsolateral prefrontal cortex, and from nucleus tractus solitarii to locus coeruleus and ventromedial prefrontal cortex. Changes in brain activity and connectivity after e-RAVANS were significantly associated with a reduction in depressive and anxiety symptoms.

CONCLUSIONS

Our study suggests exhalatory-gated RAVANS effectively modulates brain circuitries regulating response to negative stress and is associated with significant acute reduction of depressive and anxiety symptomatology in women with recurrent MDD. Findings suggest a potential non-pharmacologic intervention for acute relief of depressive symptomatology in MDD.

Association between the 2d:4d and cardiovascular risk factors: Body mass index, blood pressure and body fat

OBJECTIVES

To examine the relationship between the cardiovascular risk factors such as obesity as measured by Body mass index (BMI), body fat and blood pressure with the second to fourth digit ratio (2d:4d); a prenatal testosterone exposure marker.

METHODS

The 2d:4d for both hands were measured for the Indian male subjects' (n = 1217). Subject's anthropometric parameters such as height, weight, skinfold thicknesses at various regions and blood pressure measurements were collected in a cross-sectional study with a convenient sampling approach. The association between digit ratio and the other variables were examined using analysis of variance, Pearson's correlation test and linear regression methods.

RESULTS

The study included 1193 subjects and all were males aged 19.69 ± 5.38 years (range 13 to 40 years). The subjects' body mass index (BMI) was 19.45 ± 3.82 and right and left hand 2d:4d were 0.958 ± 0.054, and 0.958 ± 0.061 respectively. The systolic blood pressure (SBP) and BMI significantly differed between the higher and lower half of right 2d:4d. The left hand 2d:4d was significantly correlated with SBP (r = 0.075, p = 0.028) and significantly differed between different hypertensive groups (p < 0.003, F = 3.552, df = 5).

CONCLUSION

The study observed an association between 2d:4d with hypertension and BMI among young Indian population, emphasizing the effect of prenatal testosterone on late life cardiovascular risk factor.

Maternal Immune activity during pregnancy and socioeconomic disparities in children's self-regulation

Maternal immune activity during pregnancy has been associated with risk for psychiatric disorders in offspring, but less is known about its implications for children's emotional and behavioral development. This study examined whether concentrations of five cytokines assayed from prenatal serum were associated with socioeconomic status (SES) and racial disparities in their offspring's self-regulation abilities. Participants included 1628 women in the Collaborative Perinatal Project (CPP). Seven behavioral items conceptually related to self-regulation were rated by CPP psychologists when children were 4 years old. Concentrations of interleukin (IL)-1β, IL-6, IL-8, tumor necrosis factor (TNF)-α, and IL-10 were assessed. Covariates included child sex and mother's age, psychiatric disorders, and medical conditions during pregnancy. There were significant SES differences in child self-regulation, with higher SES children scoring higher on self-regulation (β = 0.18, 95% CI [0.11, 0.25]), but no racial differences. The concentration of IL-8 in maternal serum was associated with higher child self-regulation, β = 0.09, 95% CI [0.02, 0.16]. In mediation analyses, variation in maternal IL-8 contributed to the association between family SES and child self-regulation (β = 0.02, 95% CI [0.003, 0.030]), explaining about one-tenth of the SES disparities. This study suggests pregnancy as an early sensitive period and maternal immune activity as an important context for child development.

Roles for androgens in mediating the sex differences of neuroendocrine and behavioral stress responses

Estradiol and testosterone are powerful steroid hormones that impact brain function in numerous ways. During development, these hormones can act to program the adult brain in a male or female direction. During adulthood, gonadal steroid hormones can activate or inhibit brain regions to modulate adult functions. Sex differences in behavioral and neuroendocrine (i.e., hypothalamic pituitary adrenal (HPA) axis) responses to stress arise as a result of these organizational and activational actions. The sex differences that are present in the HPA and behavioral responses to stress are particularly important considering their role in maintaining homeostasis. Furthermore, dysregulation of these systems can underlie the sex biases in risk for complex, stress-related diseases that are found in humans. Although many studies have explored the role of estrogen and estrogen receptors in mediating sex differences in stress-related behaviors and HPA function, much less consideration has been given to the role of androgens. While circulating androgens can act by binding and activating androgen receptors, they can also act by metabolism to estrogenic molecules to impact estrogen signaling in the brain and periphery. This review focuses on androgens as an important hormone for modulating the HPA axis and behaviors throughout life and for setting up sex differences in key stress regulatory systems that could impact risk for disease in adulthood. In particular, impacts of androgens on neuropeptide systems known to play key roles in HPA and behavioral responses to stress (corticotropin-releasing factor, vasopressin, and oxytocin) are discussed. A greater knowledge of androgen action in the brain is key to understanding the neurobiology of stress in both sexes.

Impact of sex and depressed mood on the central regulation of cardiac autonomic function

Cardiac autonomic dysregulation has been implicated in the comorbidity of major psychiatric disorders and cardiovascular disease, potentially through dysregulation of physiological responses to negative stressful stimuli (here, shortened to stress response). Further, sex differences in these comorbidities are substantial. Here, we tested the hypothesis that mood- and sex-dependent alterations in brain circuitry implicated in the regulation of the stress response are associated with reduced peripheral parasympathetic activity during negative emotional arousal. Fifty subjects (28 females) including healthy controls and individuals with major depression, bipolar psychosis and schizophrenia were evaluated. Functional magnetic resonance imaging and physiology (cardiac pulse) data were acquired during a mild visual stress reactivity challenge. Associations between changes in activity and functional connectivity of the stress response circuitry and variations in cardiovagal activity [normalized high frequency power of heart rate variability (HFn)] were evaluated using GLM analyses, including interactions with depressed mood and sex across disorders. Our results revealed that in women with high depressed mood, lower cardiovagal activity in response to negative affective stimuli was associated with greater activation of hypothalamus and right amygdala and reduced connectivity between hypothalamus and right orbitofrontal cortex, amygdala, and hippocampus. No significant associations were observed in women with low levels of depressed mood or men. Our results revealed mood- and sex-dependent interactions in the central regulation of cardiac autonomic activity in response to negative affective stimuli. These findings provide a potential pathophysiological mechanism for previously observed sex differences in the comorbidity of major depression and cardiovascular disease.

Prenatal Stress, Mood, and Gray Matter Volume in Young Adulthood

This study aimed to determine whether prenatal stress, measured by the number of stressful life events during the first 20 weeks of pregnancy, might relate to mood dysregulation and altered brain structure in young adulthood. Participants included 93 young adults from a community-based birth cohort from the Czech Republic. Information on prenatal stress exposure was collected from their mothers in 1990-1992. Magnetic resonance imaging (MRI) and mood-related data were collected from the young adults in 2015. MRI analyses focused on overall gray matter (GM) volume and GM volume of cortical regions previously associated with major depression. Higher prenatal stress predicted more mood dysregulation, lower overall GM volume, and lower GM volume in mid-dorsolateral frontal cortex, anterior cingulate cortex, and precuneus in young adulthood. We observed no prenatal stress by sex interactions for any of the relations. We conclude that prenatal stress is an important risk factor that relates to worse mood states and altered brain structure in young adulthood irrespective of sex. Our results point to the importance and long-lasting effects of prenatal programming and suggest that offspring of mothers who went through substantial stress during pregnancy might benefit from early intervention that would reduce the odds of mental illness in later life.

Effects of Estrogen in Gender-dependent Fetal Programming of Adult Cardiovascular Dysfunction

BACKGROUND

Epidemiological studies and experimental studies have demonstrated that intrauterine adverse environment increases the risk of Cardiovascular Disease (CVD) in adulthood. However, whether an individual develops a cardiovascular dysfunctional phenotype may depend on genetic background, age, and sex.

METHODS

In this review, we summarize some of the recent experimental animal studies in the developmental programming of adult CVD with an emphasis on sex differences and the potential role of estrogen in mediating sexual dimorphism.

RESULTS

Few epidemiological studies report the effect of sex on the developmental programming of CVD. However, numerous experimental animal studies have shown a sex difference in fetal programming of adult cardiovascular dysfunction. Most of the animal studies indicate that male offspring develop cardiovascular dysfunction and CVD in adulthood, whereas adult females appear to be protected. Estrogen is one of the key factors that contributes to the sex difference of adult CVD. Estrogen/its Receptor (ER) may interact with the RAS system by changes of DNA methylation patterns at the target gene promoter, serve as an antioxidant to counteract the prenatal insults-induced heightened ROS, and function as an eNOS activator to increase vasodilation, resulting in the protection of female offspring from the development of hypertension and other CVDs.

CONCLUSION

These studies suggest that estrogen/ER may contribute to sex differences in cardiovascular response to an adverse intrauterine environment and play a significant role in modulating the cardiovascular response in adulthood.

Hypothalamic-pituitary-adrenal axis and stress

Stress is associated with the onset of several stress-related mental disorders that occur more frequently in women than in men, such as major depression or posttraumatic stress disorder (PTSD). The hypothalamic-pituitary-adrenal (HPA) axis is the major component of the neuroendocrine network responding to internal and external challenges. The proper functioning of the HPA axis is critical for the maintenance of mental and physical health, as dysregulations of the HPA axis have been linked to several mental and physical disorders. Numerous studies have observed distinct sex differences in the regulation of the HPA axis in response to stress, and it is supposed that these differences may partially explain the female predominance in stress-related mental disorders. Preclinical models have clearly shown that the HPA axis in females is activated more rapidly and produces a larger output of stress hormones than in males. However, studies with humans often produced inconsistent findings, which might be traced back to the variation of investigated stressors, the use of contraceptives in some of the studies, and different menstrual cycle stages of the female subjects. This article discusses rodent and human literature of sex differences in the function of the HPA axis.

Sex-dependent associations between maternal prenatal cortisol and child callous-unemotional traits: Findings from the Wirral Child Health and Development Study

BACKGROUND

Elevated maternal glucocorticoids during pregnancy may impact on fetal development in a sex-dependent way, leading to increased amygdala activation and increased risk for internalising disorders in females. Based on evidence implicating reduced amygdala activation in callous-unemotional (CU) traits, we predicted that elevated maternal cortisol in pregnancy would be associated with lower CU traits and elevated anxious-depressed symptoms, only in girls.

METHODS

Participants were 225 members of a stratified subsample within an epidemiological longitudinal cohort (WCHADS). Salivary cortisol was measured over two days at 32 weeks gestation (on waking, 30-min post-waking and during the evening) and the log of the area under the curve (LogAUC) was calculated as an index of diurnal cortisol. Mothers reported on child CU traits and anxious-depressed symptoms at 2.5, 3.5 and 5.0 years of age.

RESULTS

As predicted there was a sex of child by cortisol interaction (p < .001) whereby elevated maternal cortisol was associated with lower child CU traits, explaining 25% of the variance, in girls, but not in boys. This effect remained when controlling for relevant confounders and anxious-depressed symptoms. By contrast, elevated maternal cortisol did not predict higher anxious-depressed symptoms in girls.

CONCLUSIONS

The study adds to growing evidence for sex-dependent effects of elevated maternal cortisol during pregnancy on early child psychopathology, consistent with mediation by elevated amygdala activation. The conditions under which, in girls, this is associated with heightened responsiveness to others' distress characteristic of low CU traits, or with increased affective symptoms, require further study.

Correlates of low-adherence to oral hypoglycemic medications among Hispanic/Latinos of Mexican heritage with Type 2 Diabetes in the United States

AIMS

We examined psychosocial- and social/economic factors related to low medication adherence, and sex differences, among 279 adults of Mexican heritage with Type 2 Diabetes.

METHODS

Self-report and health record data were used for cross-sectional analyses. Bivariate analyses tested the association of demographic, psychosocial (depression, anxiety, stress) and social/economic factors (insurance type, health literacy, social support) and medication adherence measured by proportion of days covered. Hierarchical regression analyses examined associations between demographic, psychosocial- and social/economic- related factors and low medication adherence stratified by sex.

RESULTS

More males than females demonstrated low adherence to hypoglycemic medications (75.0.% vs. 70.3%) (p < 0.05). We found significant differences between levels social support and medication adherence (p < 0.05). In hierarchical models, being US born and higher levels of social support were associated with low adherence among males (p < 0.05, and p < 0.001).

CONCLUSIONS

Approximately 72% of Mexican heritage adults demonstrated low adherence (PDC ≤ 0.50) to their hypoglycemic regimen, and gender differences exist. Interventions should address gender differences in preferences for social support to improve medication-taking behaviors among Mexican heritage males.

Sex differences in the hypothalamic-pituitary-adrenal axis' response to stress: an important role for gonadal hormones

The hypothalamic-pituitary-adrenal (HPA) axis, a neuroendocrine network that controls hormonal responses to internal and external challenges in an organism's environment, exhibits strikingly sex-biased activity. In adult female rodents, acute HPA function following a stressor is markedly greater than it is in males, and this difference has largely been attributed to modulation by the gonadal hormones testosterone and estradiol. These gonadal hormones are produced by the hypothalamic-pituitary-gonadal (HPG) axis and have been shown to determine sex differences in adult HPA function after acute stress via their activational and organizational effects. Although these actions of gonadal hormones are well supported, the possibility that sex chromosomes similarly influence HPA activity is unexplored. Moreover, questions remain regarding sex differences in the activity of the HPA axis following chronic stress and the underlying contributions of gonadal hormones and sex chromosomes. The present review examines what is currently known about sex differences in the neuroendocrine response to stress, as well as outstanding questions regarding this sex bias. Although it primarily focuses on the rodent literature, a brief discussion of sex differences in the human HPA axis is also included.

Sex differences in major depression and comorbidity of cardiometabolic disorders: impact of prenatal stress and immune exposures

Major depressive disorder topped ischemic heart disease as the number one cause of disability worldwide in 2012, and women have twice the risk of men. Further, the comorbidity of depression and cardiometabolic disorders will be one of the primary causes of disability worldwide by 2020, with women at twice the risk. Thus, understanding the sex-dependent comorbidities has public health consequences worldwide. We propose here that sex differences in MDD-cardiometabolic comorbidity originate, in part, from pathogenic processes initiated in fetal development that involve sex differences in shared pathophysiology between the brain, the vascular system, the CNS control of the heart and associated hormonal, immune, and metabolic physiology. Pathways implicate neurotrophic and angiogenic growth factors, gonadal hormone receptors, and neurotransmitters such as gamma amino butyric acid (GABA) on neuronal and vascular development of HPA axis regions, such as the paraventricular nucleus (PVN), in addition to blood pressure, in part through the renin-angiotensin system, and insulin and glucose metabolism. We show that the same prenatal exposures have consequences for sex differences across multiple organ systems that, in part, share common pathophysiology. Thus, we believe that applying a sex differences lens to understanding shared biologic substrates underlying these comorbidities will provide novel insights into the development of sex-dependent therapeutics. Further, taking a lifespan perspective beginning in fetal development provides the opportunity to target abnormalities early in the natural history of these disorders in a sex-dependent way.

Early post-conception maternal cortisol, children’s HPAA activity and DNA methylation profiles

The hypothalamic–pituitary–adrenal axis (HPAA) plays a critical role in the functioning of all other biological systems. Thus, studying how the environment may influence its ontogeny is paramount to understanding developmental origins of health and disease. The early post-conceptional (EPC) period could be particularly important for the HPAA as the effects of exposures on organisms’ first cells can be transmitted through all cell lineages. We evaluate putative relationships between EPC maternal cortisol levels, a marker of physiologic stress, and their children’s pre-pubertal HPAA activity (n=22 dyads). Maternal first-morning urinary (FMU) cortisol, collected every-other-day during the first 8 weeks post-conception, was associated with children’s FMU cortisol collected daily around the start of the school year, a non-experimental challenge, as well as salivary cortisol responses to an experimental challenge (all Ps<0.05), with some sex-related differences. We investigated whether epigenetic mechanisms statistically mediated these links and, therefore, could provide cues as to possible biological pathways involved. EPC cortisol was associated with >5% change in children’s buccal epithelial cells’ DNA methylation for 867 sites, while children’s HPAA activity was associated with five CpG sites. Yet, no CpG sites were related to both, EPC cortisol and children’s HPAA activity. Thus, these epigenetic modifications did not statistically mediate the observed physiological links. Larger, prospective peri-conceptional cohort studies including frequent bio-specimen collection from mothers and children will be required to replicate our analyses and, if our results are confirmed, identify biological mechanisms mediating the statistical links observed between maternal EPC cortisol and children’s HPAA activity.

Developmental origins of depression-related white matter properties: Findings from a prenatal birth cohort

Depression is the leading cause of years lost due to disability worldwide. Still, the mechanisms underlying its development are not well understood. This study aimed to evaluate white-matter properties associated with depressive symptomatology in young adulthood and their developmental origins. Diffusion tensor imaging and assessment of depressive symptomatology were conducted in 128 young adults (47% male, age 23-24) from a prenatal birth cohort (European Longitudinal Study of Pregnancy and Childhood). For a subset of these individuals, the database included information on prenatal stress (n = 93) and depressive symptoms during adolescence (assessed repeatedly at age 15 and 19). Depressive symptoms in young adulthood were associated with lower fractional anisotropy in the left and right cingulum and higher fractional anisotropy in the right corticospinal tract and superior longitudinal fasciculus. Further analyses revealed that prenatal stress and depressive symptomatology during adolescence were independent predictors of altered white-matter properties in the cingulum in young adulthood. We conclude that typically developing young adults with more depressive symptoms already exhibit tract-specific alterations in white-matter properties and that prenatal stress and depressive symptomatology during adolescence might contribute to their development.

Perinatal stress and human hippocampal volume: Findings from typically developing young adults

The main objective of this study was to investigate the impact of prenatal and early postnatal stress on hippocampal volume in young adulthood. In sharp contrast to numerous results in animal models, our data from a neuroimaging follow-up (n = 131) of a community-based birth cohort from the Czech Republic (European Longitudinal Study of Pregnancy and Childhood) showed that in typically developing young adults, hippocampal volume was not associated with birth weight, stressful life events during the prenatal or early postnatal period, or dysregulated mood and wellbeing in the mother during the early postnatal period. Interestingly, mother’s anxiety/co-dependence during the first weeks after birth did show long-lasting effects on the hippocampal volume in young adult offspring irrespective of sex. Further analyses revealed that these effects were subfield-specific; present in CA1, CA2/3, CA4, GC-DG, subiculum, molecular layer, and HATA, hippocampal subfields identified by translational research as most stress- and glucocorticoid-sensitive, but not in the remaining subfields. Our findings provide evidence that the type of early stress is critical when studying its effects on the human brain.

Embryonic Exposure to Dexamethasone Affects Nonneuronal Cells in the Adult Paraventricular Nucleus of the Hypothalamus

Neurons in the paraventricular nucleus of the hypothalamus (PVN) integrate peripheral signals and coordinate responses that maintain numerous homeostatic functions. An excess of glucocorticoids during fetal development results in long-lasting consequences tied to disrupted PVN development. The PVN contains a distinct neuronal population and a threefold greater vascular density than the surrounding brain regions that prepubertally is reduced in offspring exposed to excess glucocorticoids in utero. This study expands the examination of sex-specific nonneuronal PVN composition by examining astrocytes, astrocytic endfeet, and pericytes. Blood-brain barrier (BBB) competency and composition were examined along with depressive-like behavior and hypothalamic-pituitary-adrenal function in male and female mice. For PVN vasculature, female offspring of vehicle (veh)-treated mothers had significantly more astrocytes and pericytes than male offspring from the same litters. Female offspring from dexamethasone (dex)-treated mothers had significantly lower levels of astrocytes than female offspring from veh-treated mothers, whereas male offspring from dex-treated mothers had greater levels of pericytes compared with veh-treated male offspring. Using the tail-suspension test, male and female offspring from dex-treated mothers had significantly shorter latencies to immobility, indicating an increase in depression-like behavior, and showed greater plasma corticosterone after restraint stress, which was significantly greater in female offspring from dex-treated mothers even after recovery. Therefore, in addition to long-term sex differences in cellular components of the BBB in the PVN that were differentially regulated by fetal glucocorticoid exposure, there were behavioral differences observed into early adulthood in a sex-specific manner.

Thinking Across Generations: Unique Contributions of Maternal Early Life and Prenatal Stress to Infant Physiology

OBJECTIVE

Respiratory sinus arrhythmia (RSA) is a parasympathetic-mediated biomarker of self-regulation linked to lifespan mental and physical health outcomes. Intergenerational impacts of mothers' exposure to prenatal stress have been demonstrated, but evidence for biological embedding of maternal preconception stress, including adverse childhood experiences (ACEs), on infant RSA is lacking. We examine the independent effects of maternal ACEs and prenatal stress on infant RSA, seeking to broaden the understanding of the earliest origins of mental and physical health risk.

METHOD

Mothers reported on ACEs and prenatal stress. RSA was recorded in a sample of 167 4-month-old infants (49% female and 51% male) during a dyadic stressor, the Still Face Paradigm.

RESULTS

Independent contributions of maternal ACEs and prenatal stress to infant RSA were observed. High maternal ACEs were associated with lower RSA, whereas prenatal stress was associated with failure to recover following the stressor. Sex but not race differences were observed. Prenatal stress was associated with higher RSA among boys but lower RSA among girls.

CONCLUSION

Infants' RSA is affected by mothers' life course experiences of stress, with ACEs predicting a lower set point and prenatal stress dampening recovery from stress. For prenatal stress but not ACEs, patterns vary across sex. Findings underscore that stress-reducing interventions for pregnant women or those considering pregnancy may lead to decreased physical and mental health risk across generations.

Environmental perturbation of the circadian clock during pregnancy leads to transgenerational mood disorder-like behaviors in mice

It remains unknown whether chronic circadian disturbance (CCD) during pregnancy can lead to mood disorders in the offspring. Here we show that pregnant mice in the F0 generation that were exposed to CCD stress displayed depression-like behaviors, and produced offspring in the F1 and F2 generations that also exhibited mood-associated behavioral phenotypes despite the lack of direct stressful experiences during their postnatal or adult period. Prenatal CCD stress was correlated with the elevation of plasma corticosterone levels in F1 mice. Furthermore, the diurnal expression profiles of core circadian clock genes were disrupted in the suprachiasmatic nucleus of F1 mice. Proteomics analysis revealed that prenatal CCD stress resulted in distinct changes in protein expression in the hypothalamus of female F1 mice, in particular proteins that were associated with cellular activities, metabolism, development and diseases. Sex-specific differences in melanocortin 4 receptor expression were apparent in the CCD F1 generation. We conclude that maternal exposure to chronic circadian disturbance during pregnancy can lead to sex-specific mood disorders that persist for at least two filial generations. The underlying mechanisms may depend on transgenerational changes in plasma corticosterone levels, circadian pacemaking, and hypothalamic protein expression.

Between-litter variation in developmental studies of hormones and behavior: Inflated false positives and diminished power

Developmental studies of hormones and behavior often include littermates-rodent siblings that share early-life experiences and genes. Due to between-litter variation (i.e., litter effects), the statistical assumption of independent observations is untenable. In two literatures-natural variation in maternal care and prenatal stress-entire litters are categorized based on maternal behavior or experimental condition. Here, we (1) review both literatures; (2) simulate false positive rates for commonly used statistical methods in each literature; and (3) characterize small sample performance of multilevel models (MLM) and generalized estimating equations (GEE). We found that the assumption of independence was routinely violated (>85%), false positives (α=0.05) exceeded nominal levels (up to 0.70), and power (1-β) rarely surpassed 0.80 (even for optimistic sample and effect sizes). Additionally, we show that MLMs and GEEs have adequate performance for common research designs. We discuss implications for the extant literature, the field of behavioral neuroendocrinology, and provide recommendations.

Prenatal stress-immune programming of sex differences in comorbidity of depression and obesity/metabolic syndrome

Major depressive disorder (MDD) is the number one cause of disability worldwide and is comorbid with many chronic diseases, including obesity/metabolic syndrome (MetS). Women have twice as much risk for MDD and comorbidity with obesity/MetS as men, although pathways for understanding this association remain unclear. On the basis of clinical and preclinical studies, we argue that prenatal maternal stress (ie, excess glucocorticoid expression and associated immune responses) that occurs during the sexual differentiation of the fetal brain has sex-dependent effects on brain development within highly sexually dimorphic regions that regulate mood, stress, metabolic function, the autonomic nervous system, and the vasculature. Furthermore, these effects have lifelong consequences for shared sex-dependent risk of MDD and obesity/MetS. Thus, we propose that there are shared biologic substrates at the anatomical, molecular, and/or genetic levels that produce the comorbid risk for MDD-MetS through sex-dependent fetal origins.

Sex differences in microRNA-mRNA networks: examination of novel epigenetic programming mechanisms in the sexually dimorphic neonatal hypothalamus

BACKGROUND

Sexual differentiation of the male brain, and specifically the stress circuitry in the hypothalamus, is primarily driven by estrogen exposure during the perinatal period. Surprisingly, this single hormone promotes diverse programs of sex-specific development that vary widely between different cell types and across the developing male brain. The complexity of this phenomenon suggests that additional layers of gene regulation, including microRNAs (miRNAs), must act downstream of estrogen to mediate this specificity.

METHODS

To identify noncanonical mediators of estrogen-dependent sex-specific neural development, we assayed the miRNA complement of the mouse PN2 hypothalamus by microarray following an injection of vehicle or the aromatase inhibitor, formestane. Initially, multivariate analyses were used to test the influence of sex and experimental group on the miRNA environment as a whole. Then, we utilized traditional hypothesis testing to identify individual miRNA with significantly sex-biased expression. Finally, we performed a transcriptome-wide mapping of Argonaute footprints by high-throughput sequencing of RNA isolated by cross-linking immunoprecipitation (Ago HITS-CLIP) to empirically characterize targeting relationship between estrogen-responsive miRNAs and their messenger RNA (mRNA) targets.

RESULTS

In this study, we demonstrated that the neonatal hypothalamic miRNA environment has robust sex differences and is dynamically responsive to estrogen. Analyses identified 162 individual miRNAs with sex-biased expression, 92 of which were estrogen-responsive. Examining the genomic distribution of these miRNAs, we found three miRNA clusters encoded within a 175-kb region of chromosome 12 that appears to be co-regulated by estrogen, likely acting broadly to alter the epigenetic programming of this locus. Ago HITS-CLIP analysis uncovered novel miRNA-target interactions within prototypical mediators of estrogen-driven sexual differentiation of the brain, including Esr1 and Cyp19a1. Finally, using Gene Ontology annotations and empirically identified miRNA-mRNA connections, we identified a gene network regulated by estrogen-responsive miRNAs that converge on biological processes relevant to sexual differentiation of the brain.

CONCLUSIONS

Sexual differentiation of the perinatal brain, and that of stress circuitry in the hypothalamus specifically, seems to be particularly susceptible to environmental programming effects. Integrating miRNA into our conceptualization of factors, directing differentiation of this circuitry could be an informative next step in efforts to understand the complexities behind these processes.

Grandmaternal stress during pregnancy and DNA methylation of the third generation: an epigenome-wide association study

Stress during pregnancy may impact subsequent generations, which is demonstrated by an increased susceptibility to childhood and adulthood health problems in the children and grandchildren. Although the importance of the prenatal environment is well reported with regards to future physical and emotional outcomes, little is known about the molecular mechanisms that mediate the long-term consequences of early stress across generations. Recent studies have identified DNA methylation as a possible mediator of the impact of prenatal stress in the offspring. Whether psychosocial stress during pregnancy also affects DNA methylation of the grandchildren is still not known. In the present study we examined the multigenerational hypothesis, that is, grandmaternal exposure to psychosocial stress during pregnancy affecting DNA methylation of the grandchildren. We determined the genome-wide DNA methylation profile in 121 children (65 females and 56 males) and tested for associations with exposure to grandmaternal interpersonal violence during pregnancy. We observed methylation variations of five CpG sites significantly (FDR<0.05) associated with the grandmother's report of exposure to violence while pregnant with the mothers of the children. The results revealed differential methylation of genes previously shown to be involved in circulatory system processes (FDR<0.05). This study provides support for DNA methylation as a biological mechanism involved in the transmission of stress across generations and motivates further investigations to examine prenatal-dependent DNA methylation as a potential biomarker for health problems.

Evening salivary cortisol and alpha-amylase at 14months and neurodevelopment at 4years: Sex differences

Stress system activity in early life can have long-term effects on neurodevelopment. The main aim of this study was to assess the association of child evening salivary cortisol and alpha-amylase basal levels at 14months of age with longer-term neuropsychological development at 4years in a low-risk population-based birth cohort derived from the INMA (Environment and Childhood) project in Spain. We included 186 parent-children pairs with information on both stress system activity and neurodevelopment. Both stress markers at 14months of age showed an association with neuropsychological development at 4years. Salivary cortisol showed a sex-specific pattern of association. In girls, cortisol levels at 14months were negatively associated with cognitive development [long-term declarative memory (β=-17.8, p=0.028; 95% CI=-33.2 to -2.5); executive function (β=-9.8, p=0.08; 95% CI=-21 to 1)] and gross motor development (β=-13; p=0.022; 95% CI=-24 to -2), whereas in boys cortisol levels were negatively associated with socioemotional development [autistic-like behaviours: Incidence Rate Ratio (IRR)=1.6, p=0.039; 95% CI=1.01 to 2.41]. Salivary alpha-amylase was positively associated with socioemotional development in boys only [social competence (β=2.11, p=0.013; 95% CI=0.47 to 3.72), autistic-like behaviours (IRR=0.93, p=0.042; 95% CI=0.87 to 0.99) and hyperactivity symptoms (IRR=0.81, p=0.021; 95% CI=0.69 to 0.97)]. These results suggest that stress system activity in early life is associated with longer-term neurodevelopment and that sex is an important factor in this relationship.

Socioeconomic disadvantage, gestational immune activity, and neurodevelopment in early childhood

Children raised in economically disadvantaged households face increased risks of poor health in adulthood, suggesting that inequalities in health have early origins. From the child's perspective, exposure to economic hardship may begin as early as conception, potentially via maternal neuroendocrine-immune responses to prenatal stressors, which adversely impact neurodevelopment. Here we investigate whether socioeconomic disadvantage is associated with gestational immune activity and whether such activity is associated with abnormalities among offspring during infancy. We analyzed concentrations of five immune markers (IL-1β, IL-6, IL-8, IL-10, and TNF-α) in maternal serum from 1,494 participants in the New England Family Study in relation to the level of maternal socioeconomic disadvantage and their involvement in offspring neurologic abnormalities at 4 mo and 1 y of age. Median concentrations of IL-8 were lower in the most disadvantaged pregnancies [-1.53 log(pg/mL); 95% CI: -1.81, -1.25]. Offspring of these pregnancies had significantly higher risk of neurologic abnormalities at 4 mo [odds ratio (OR) = 4.61; CI = 2.84, 7.48] and 1 y (OR = 2.05; CI = 1.08, 3.90). This higher risk was accounted for in part by fetal exposure to lower maternal IL-8, which also predicted higher risks of neurologic abnormalities at 4 mo (OR = 7.67; CI = 4.05, 14.49) and 1 y (OR = 2.92; CI = 1.46, 5.87). Findings support the role of maternal immune activity in fetal neurodevelopment, exacerbated in part by socioeconomic disadvantage. This finding reveals a potential pathophysiologic pathway involved in the intergenerational transmission of socioeconomic inequalities in health.

Effects of perinatal diet and prenatal stress on the behavioural profile of aged male and female rats

The present work studies whether chronic prenatal stress (PS) influences the long-term sex-dependent neuropsychological status of offspring and the effects of an early dietary intervention in the dam. In addition, dams were fed with either a high-fat sugar diet (HFSD) or methyl donor supplemented diet (MDSD). PS procedure did not affect body weight of the offspring. MDSD induced decreases in body weight both in male and female offspring (1 month) that were still present in aged rats. HFSD induced an increase in body weight both in male and female offspring that did not persist in aged rats. In the Porsolt forced swimming test, only young males showed increases in immobility time that were reversed by MDSD. In old female rats (20 months), PS-induced cognitive impairment in both the novel object recognition test (NORT) and in the Morris water maze that was reversed by MDSD, whereas in old males, cognitive impairments and reversion by MDSD was evident only in the Morris water maze. HFSD induced cognitive impairment in both control and PS old rats, but there was no additive effect of PS and HFSD. It is proposed here that the diversity of symptoms following PS could arise from programming effects in early brain development and that these effects could be modified by dietary intake of the dam.

Gestational Hyperandrogenism in Developmental Programming

Androgen excess (hyperandrogenism) is a common endocrine disorder affecting women of reproductive age. The potential causes of androgen excess in women include polycystic ovary syndrome, congenital adrenal hyperplasia (CAH), adrenal tumors, and racial disparity among many others. During pregnancy, luteoma, placental aromatase deficiency, and fetal CAH are additional causes of gestational hyperandrogenism. The present report reviews the various phenotypes of hyperandrogenism during pregnancy and its origin, pathophysiology, and the effect of hyperandrogenism on the fetal developmental trajectory and offspring consequences.

Sex as a Biological Variable: Who, What, When, Why, and How

The inclusion of sex as a biological variable in research is absolutely essential for improving our understanding of disease mechanisms contributing to risk and resilience. Studies focusing on examining sex differences have demonstrated across many levels of analyses and stages of brain development and maturation that males and females can differ significantly. This review will discuss examples of animal models and clinical studies to provide guidance and reference for the inclusion of sex as an important biological variable relevant to a Neuropsychopharmacology audience.

Prenatal stress-immune programming of sex differences in comorbidity of depression and obesity/metabolic syndrome

Major depressive disorder (MDD) is the number one cause of disability worldwide and is comorbid with many chronic diseases, including obesity/metabolic syndrome (MetS). Women have twice as much risk for MDD and comorbidity with obesity/MetS as men, although pathways for understanding this association remain unclear. On the basis of clinical and preclinical studies, we argue that prenatal maternal stress (ie, excess glucocorticoid expression and associated immune responses) that occurs during the sexual differentiation of the fetal brain has sex-dependent effects on brain development within highly sexually dimorphic regions that regulate mood, stress, metabolic function, the autonomic nervous system, and the vasculature. Furthermore, these effects have lifelong consequences for shared sex-dependent risk of MDD and obesity/MetS. Thus, we propose that there are shared biologic substrates at the anatomical, molecular, and/or genetic levels that produce the comorbid risk for MDD-MetS through sex-dependent fetal origins.

Corticolimbic regulation of cardiovascular responses to stress

Cardiovascular disease, a leading cause of death worldwide, is frequently initiated or exacerbated by stress. In fact, chronic stress exposure and heightened reactions to acute psychological stress are both associated with increased cardiovascular morbidity. This brief review focuses on the mechanisms by which corticolimbic nuclei, critical for stress appraisal and emotional reactivity, regulate heart rate and blood pressure responses to psychological stress. Both human and rodent data are examined with a major emphasis on basic studies investigating prefrontal cortex, amygdala, and hippocampus. A detailed literature review reveals substantial limitations in our understanding of this circuitry, as well as significant opportunities for future investigation that may ultimately reduce the burden of cardiovascular illness.

Cardiovascular disease risk factors and psychological distress among Hispanics/Latinos: The Hispanic Community Health Study/Study of Latinos (HCHS/SOL)

Studies show that cardiovascular disease (CVD) risk factors are correlated with psychological distress, yet research examining these relationships among Hispanic/Latinos is lacking. The population-based Hispanic Community Health Study/Study of Latinos enrolled a cohort of Hispanic/Latino adults (N=16,415) 18-74years of age at the time of recruitment, from four US metropolitan areas, between March 2008 and June 2011. Psychological distress (i.e., 10-item Center for Epidemiological Studies Depression Scale, 10 item Spielberger Trait Anxiety Scale, and a combined depression/anxiety score), socio-demographics (i.e., age, education, income, insurance, sex, and Hispanic/Latino background), acculturation (i.e., country of birth and language preference), and traditional CVD risk factors (i.e., dyslipidemia, obesity, current cigarette smoking, diabetes, and hypertension) were assessed at baseline. Associations between CVD risk factors and psychological distress measures by sex were examined using multiple linear regression models, accounting for complex survey design and sampling weights and controlling for socio-demographic and acculturation covariates. In adjusted analyses, all three psychological distress measures were significantly related to smoking. For females, greater psychological distress was significantly related to obesity and current smoking. For males, diabetes and current smoking were associated with psychological distress. For males and females, dyslipidemia and hypertension were not associated with psychological distress after adjusting for other factors. Elevated depression and anxiety symptoms were associated with CVD risk factors for Hispanic/Latino men and women. However, these results were not consistent across Hispanic/Latino groups. As promoted by the integrative care model, psychosocial concerns should be considered in research on CVD risk and chronic disease prevention.

Prenatal immune programming of the sex-dependent risk for major depression

Maternal immune functioning during pregnancy contributes to sex-dependent deficits in neurodevelopment and to behaviors associated with affective traits in preclinical studies, and has been indirectly associated with offspring depression in epidemiologic studies. We therefore investigated the association between immune activity during pregnancy and the risk of depression among male and female offspring. We conducted a case-control study of depression (n=484 cases and n=774 controls) using data from the New England Family Study, a pregnancy cohort enrolled between 1959 and 1966 that assessed psychiatric outcomes in adult offspring (mean age=39.7 years). We assayed concentrations of three pro-inflammatory cytokines, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α, and the anti-inflammatory cytokine, IL-10, in maternal serum collected at the end of the second and beginning of the third trimesters. High maternal TNF-α was associated with reduced odds of depression among both male and female offspring (odds ratio (OR)=0.68; confidence interval (CI)=0.48, 0.98). However, when considering the TNF-α to IL-10 ratio, a measure of the ratio of pro- to anti-inflammatory loading, maternal immune effects on offspring depression differed significantly by sex (χ(2)=13.9, degrees of freedom=4, P=0.008). Among females, higher maternal TNF-α:IL-10 was associated with reduced odds of depression (OR=0.51; CI=0.32, 0.81), whereas, among males, high maternal TNF-α:IL-10 was associated with elevated odds of depression (OR=1.86; CI=1.02, 3.39). Thus, the balance between TNF-α and IL-10 in maternal prenatal serum was associated with depression in a sex-dependent manner. These findings are consistent with the role of TNF-α in the maturation of the sexually dimorphic fetal brain circuitry that regulates stress and affective responses, and support a prenatal stress-immune model of depression pathogenesis.

Maternal and pediatric health and disease: integrating biopsychosocial models and epigenetics

The concepts of allostasis (stability through adaptation) and accumulated life stress (McEwen's allostatic load) aim to understand childhood and adult outcomes. Chronic malnutrition, changes in social condition, and adverse early-life experiences may program phenotypes and contribute to long-lasting disease risk. However, integration of life course approaches, social and economic contexts, and comparison among different biopsychosocial models has not generally been explored. This review critically examines the literature and evaluates recent insights into how environmental stress can alter lifelong hypothalamic-pituitary-adrenal axis and immune system responsiveness and induce metabolic and neurodevelopmental maladaptation. Models of biopsychosocial stress overlap but may consider different conditions. Concepts include allostasis, which incorporates hormonal responses to predictable environmental changes, and Geronimus's "weathering," which aims to explain how socially structured, repeated stress can accumulate and increase disease vulnerability. Weathering emphasizes roles of internalized/interpersonal racism in outcomes disparities. For Mexican immigrants and Mexican Americans, the "acculturation" framework has proven especially useful to explore disparities, including preterm birth and neuropsychiatric risks in childhood. Complexities of stress assessments and recent research into epigenetic mechanisms mediating effects of physical, nutritional, psychological, and social stress are reviewed.

Socioeconomic disadvantage and neural development from infancy through early childhood

BACKGROUND

Early social experiences are believed to shape neurodevelopment, with potentially lifelong consequences. Yet minimal evidence exists regarding the role of the social environment on children's neural functioning, a core domain of neurodevelopment.

METHODS

We analysed data from 36 443 participants in the United States Collaborative Perinatal Project, a socioeconomically diverse pregnancy cohort conducted between 1959 and 1974. Study outcomes included: physician (neurologist or paediatrician)-rated neurological abnormality neonatally and thereafter at 4 months and 1 and 7 years; indicators of neurological hard signs and soft signs; and indicators of autonomic nervous system function.

RESULTS

Children born to socioeconomically disadvantaged parents were more likely to exhibit neurological abnormalities at 4 months [odds ratio (OR) = 1.20; 95% confidence interval (CI) = 1.06, 1.37], 1 year (OR = 1.35; CI = 1.17, 1.56), and 7 years (OR = 1.67; CI = 1.48, 1.89), and more likely to exhibit neurological hard signs (OR = 1.39; CI = 1.10, 1.76), soft signs (OR = 1.26; CI = 1.09, 1.45) and autonomic nervous system dysfunctions at 7 years. Pregnancy and delivery complications, themselves associated with socioeconomic disadvantage, did not account for the higher risks of neurological abnormalities among disadvantaged children.

CONCLUSIONS

Parental socioeconomic disadvantage was, independently from pregnancy and delivery complications, associated with abnormal child neural development during the first 7 years of life. These findings reinforce the importance of the early environment for neurodevelopment generally, and expand knowledge regarding the domains of neurodevelopment affected by environmental conditions. Further work is needed to determine the mechanisms linking socioeconomic disadvantage with children's neural functioning, the timing of such mechanisms and their potential reversibility.

Research Resource: The Dexamethasone Transcriptome in Hypothalamic Embryonic Neural Stem Cells

Exposure to excess glucocorticoids during fetal development has long-lasting physiological and behavioral consequences, although the mechanisms are poorly understood. The impact of prenatal glucocorticoids exposure on stress responses in juvenile and adult offspring implicates the developing hypothalamus as a target of adverse prenatal glucocorticoid action. Therefore, primary cultures of hypothalamic neural-progenitor/stem cells (NPSCs) derived from mouse embryos (embryonic day 14.5) were used to identify the glucocorticoid transcriptome in both males and females. NPSCs were treated with vehicle or the synthetic glucocorticoid dexamethasone (dex; 100nM) for 4 hours and total RNA analyzed using RNA-Sequencing. Bioinformatic analysis demonstrated that primary hypothalamic NPSC cultures expressed relatively high levels of a number of genes regulating stem cell proliferation and hypothalamic progenitor function. Interesting, although these cells express glucocorticoid receptors (GRs), only low levels of sex-steroid receptors are expressed, which suggested that sex-specific differentially regulated genes identified are mediated by genetic and not hormonal influences. We also identified known or novel GR-target coding and noncoding genes that are either regulated equivalently in male and female NPSCs or differential responsiveness in one sex. Using gene ontology analysis, the top functional network identified was cell proliferation and using bromodeoxyuridine (BrdU) incorporation observed a reduction in proliferation of hypothalamic NPSCs after dexamethasone treatment. Our studies provide the first characterization and description of glucocorticoid-regulated pathways in male and female embryonically derived hypothalamic NPSCs and identified GR-target genes during hypothalamic development. These findings may provide insight into potential mechanisms responsible for the long-term consequences of fetal glucocorticoid exposure in adulthood.