Hair cortisol concentrations are associated with hippocampal subregional volumes in children

Prenatal depression outcomes in the next generation: A critical review of recent DOHaD studies and recommendations for future research

Prenatal depression, a common pregnancy-related risk with a prevalence of 10-20 %, may affect in utero development and socioemotional and neurodevelopmental outcomes in the next generation. Although there is a growing body of work that suggests prenatal depression has an independent and long-lasting effect on offspring outcomes, important questions remain, and findings often do not converge. The present review examines work carried out in the last decade, with an emphasis on studies focusing on mechanisms and leveraging innovative technologies and study designs to fill in gaps in research. Overall, the past decade of research continues to suggest that prenatal depression increases risk for offspring socioemotional problems and may alter early brain development by affecting maternal-fetal physiology during pregnancy. However, important limitations remain; lack of diversity in study samples, inconsistent consideration of potential confounders (e.g., genetics, postnatal depression, parenting), and restriction of examination to narrow time windows and single exposures. On the other hand, exciting work has begun uncovering potential mechanisms underlying transmission, including alterations in mitochondria functioning, epigenetics, and the prenatal microbiome. We review the evidence to date, identify limitations, and suggest strategies for the next decade of research to detect mechanisms as well as sources of plasticity and resilience to ensure this work translates into meaningful, actionable science that improves the lives of families.

Relations of Lifetime Perceived Stress and Basal Cortisol With Hippocampal Volume Among Healthy Adolescents and Those at Clinical High Risk for Psychosis: A Structural Equation Modeling Approach

BACKGROUND

Hippocampal volume (HV) is sensitive to environmental influences. Under normative conditions in humans, HV increases linearly into childhood and asymptotes in early adulthood. Studies of humans and nonhuman animals have provided evidence of inverse relationships between several measures of stress and HV.

METHODS

Using structural equation modeling, this study aimed to characterize the relationships of age, basal cortisol, biological sex, and lifetime perceived stress with bilateral HV in a sample of healthy adolescents and adolescents at clinical high risk for psychosis (CHR-P) (N = 571, 43% female; age range = 12-19.9 years). This sample included 469 individuals at CHR-P and 102 healthy comparison participants from the combined baseline cohorts of the second and third NAPLS (North American Prodrome Longitudinal Study).

RESULTS

A structural model that constrained the individual effects of basal cortisol and perceived stress to single path coefficients, and freely estimated the effects of age and biological sex in group models, optimized model fit and parsimony relative to other candidate models. Significant inverse relationships between basal cortisol and bilateral HV were observed in adolescents at CHR-P and healthy comparison participants. Significant sex differences in bilateral HV were also observed, with females demonstrating smaller HV than males in both groups.

CONCLUSIONS

Multigroup structural equation modeling revealed heterogeneity in the relationships of age and biological sex with basal cortisol, lifetime perceived stress, and bilateral HV in individuals at CHR-P and healthy comparison participants. Moreover, the findings support previous literature indicating that elevated basal cortisol is a nonspecific risk factor for reduced HV.

Dentate Gyrus Microstructure Is Associated With Resilience After Exposure to Maternal Stress Across Two Human Cohorts

BACKGROUND

Maternal stress (MS) is a well-documented risk factor for impaired emotional development in offspring. Rodent models implicate the dentate gyrus (DG) of the hippocampus in the effects of MS on offspring depressive-like behaviors, but mechanisms in humans remain unclear. Here, we tested whether MS was associated with depressive symptoms and DG micro- and macrostructural alterations in offspring across 2 independent cohorts.

METHODS

We analyzed DG diffusion tensor imaging-derived mean diffusivity (DG-MD) and volume in a three-generation family risk for depression study (TGS; n = 69, mean age = 35.0 years) and in the Adolescent Brain Cognitive Development (ABCD) Study (n = 5196, mean age = 9.9 years) using generalized estimating equation models and mediation analysis. MS was assessed by the Parenting Stress Index (TGS) and a measure compiled from the Adult Response Survey from the ABCD Study. The Patient Health Questionnaire-9 and rumination scales (TGS) and the Child Behavior Checklist (ABCD Study) measured offspring depressive symptoms at follow-up. The Schedule for Affective Disorders and Schizophrenia-Lifetime interview was used to assign depression diagnoses.

RESULTS

Across cohorts, MS was associated with future symptoms and higher DG-MD (indicating disrupted microstructure) in offspring. Higher DG-MD was associated with higher symptom scores measured 5 years (in the TGS) and 1 year (in the ABCD Study) after magnetic resonance imaging. In the ABCD Study, DG-MD was increased in high-MS offspring who had depressive symptoms at follow-up, but not in offspring who remained resilient or whose mother had low MS.

CONCLUSIONS

Converging results across 2 independent samples extend previous rodent studies and suggest a role for the DG in exposure to MS and offspring depression.

Relationship between hair cortisol concentrations and cognitive functioning in adolescents with ADHD

Background: Our study aimed to explore whether the hair cortisol concentration (HCC), a measure of long-term cortisol output, is associated with poorer cognitive functioning in adolescents with attention deficit and hyperactivity disorder (ADHD). We further aimed to test the potential moderating effects of sex and childhood maltreatment.Methods: In this cross-sectional study, fifty-three adolescents with ADHD were studied. The ADHD Rating Scale (ADHD-RS) and Childhood Trauma Questionnaire (CTQ) were administered. Seven cognitive tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were administered, and two cognitive factors (attention and memory and executive functioning) were identified by confirmatory factor analysis. A 3-cm hair sample from the posterior vertex region of the head was obtained. HCCs were determined by a high-sensitivity enzyme immunoassay kit. Multiple linear regression analyses were used to explore the association between HCCs and either cognitive performance or ADHD severity while adjusting for sex, childhood maltreatment and the ADHD-RS total score.Results: Sex moderated the relationship between HCCs and attention/memory confirmatory factor analysis (CFA) scores, with better performance in boys with higher HCCs. HCCs were not associated with executive functioning or ADHD symptoms. Childhood maltreatment was associated with inattention symptoms in adolescents with ADHD.Conclusions: Our study suggests that HCCs are positively associated with attention and memory performance in adolescents with ADHD, with a moderating effect of sex (the relationship is strongest in boys).

Associations between cortisol stress responses and limbic volume and thickness in young adults: An exploratory study

The investigation of the relationship between neural measures of limbic structures and hypothalamic pituitary adrenal axis responses to acute stress exposure in healthy young adults has so far focused in particular on task-based and resting state functional connectivity studies. Thus, the present study examined the association between limbic volume and thickness measures and acute cortisol responses to the psychosocial stress paradigm ScanSTRESS. Using Permutation Analysis of Linear Models controlling for sex, age and total brain volume, the associations between (sex-specific) cortisol increases and human connectome project style anatomical variables of limbic structures (i.e. volume and thickness) were investigated in 66 healthy and young (18-33 years) subjects (35 men, 31 women taking oral contraceptives). In addition, exploratory (sex-specific) bivariate correlations between cortisol increases and structural measures were conducted. The present data provide interesting new insights into the involvement of striato-limbic structures in psychosocial stress processing, suggesting that acute cortisol stress responses are also associated with mere structural measures of the human brain. Thus, our preliminary findings suggest that not only situation- and context-dependent reactions of the limbic system (i.e. blood oxygenation level-dependent reactions) are related to acute (sex-specific) cortisol stress responses but also basal and somewhat more constant structural measures. Our study hereby paves the way for further analyses in this context and highlights the relevance of the topic.

Household socioeconomic status relates to specific hippocampal subfield volumes across development

The hippocampus is composed of cytoarchitecturally distinct subfields that support specific memory functions. Variations in total hippocampal volume across development have been linked to socioeconomic status (SES), a proxy for access to material resources, medical care, and quality education. High childhood household SES is associated with greater cognitive abilities in adulthood. Currently, it is not known whether household SES differentially impacts specific hippocampal subfield volumes. We assessed susceptibility of subfields to variations in household SES across development in a sample of 167 typically developing 5- to 25-year-old. Bilateral cornu ammonis (CA) 1-2, combined CA3-dentate gyrus (DG), and subiculum (Sub) volumes were measured by highly reliable manual segmentation of high-resolution T2-weighted images and adjusted for intracranial volume. A summary component score of SES measures (paternal education, maternal education, and income-to-needs ratio) was used to examine variability in volumes across ages. We did not identify age-related differences in any of the regional volumes, nor did age modify SES-related effects. Controlling for age, larger volumes of CA3-DG and CA1-2 were associated with lower SES, while Sub volume was not. Overall, these findings support the specific impact of SES on CA3-DG and CA1-2 and highlight the importance of considering environmental influences on hippocampal subfield development.

Butyrate ameliorates chronic alcoholic central nervous damage by suppressing microglia-mediated neuroinflammation and modulating the microbiome-gut-brain axis

BACKGROUND

Alcohol abuse triggers neuroinflammation, leading to neuronal damage and further memory and cognitive impairment. Few satisfactory advances have been made in the management of alcoholic central nervous impairment. Therefore, novel and more practical treatment options are urgently needed. Butyrate, a crucial metabolite of short-chain fatty acids (SCFAs), has been increasingly demonstrated to protect against numerous metabolic diseases. However, the impact of butyrate on chronic alcohol consumption-induced central nervous system (CNS) lesions remains unknown.

METHODS

In this study, we assessed the possible effects and underlying mechanisms of butyrate on the attenuation of alcohol-induced CNS injury in mice. Firstly, sixty female C57BL/6 J mice were randomly divided into 4 groups: pair-fed (PF) group (PF/CON), alcohol-fed (AF) group (AF/CON), PF with sodium butyrate (NaB) group (PF/NaB) and AF with NaB group (AF/NaB). Each group was fed a modified Lieber-DeCarli liquid diet with or without alcohol. After six weeks of feeding, the mice were euthanized and the associated indicators were investigated.

RESULTS

As indicated by the behavioral tests and brain morphology, dietary NaB administration significantly ameliorated aberrant behaviors, including locomotor hypoactivity, anxiety disorder, depressive behavior, impaired learning, spatial recognition memory, and effectively reduced chronic alcoholic central nervous system damage. To further understand the underlying mechanisms, microglia-mediated inflammation and the associated M1/M2 polarization were measured separately. Firstly, pro-inflammatory TNF-α, IL-1β, and IL-6 in brain and peripheral blood circulation were decreased, but IL-10 were increased in the AF/NaB group compared with the AF/CON group. Consistently, the abnormal proportions of activated and resting microglial cells in the hippocampus and cortex regions after excessive alcohol consumption were significantly reduced with NaB treatment. Moreover, the rectification of microglia polarization (M1/M2) imbalance was found after NaB administration via binding GPR109A, up-regulating the expression of PPAR-γ and down-regulating TLR4/NF-κB activation. In addition to the direct suppression of neuroinflammation, intriguingly, dietary NaB intervention remarkably increased the levels of intestinal tight junction protein occludin and gut morphological barrier, attenuated the levels of serum lipopolysaccharide (LPS) and dysbiosis of gut microbiota, suggesting that NaB supplementation effectively improved the integrity and permeability of gut microecology. Finally, the neurotransmitters including differential Tryptophan (Trp) and Kynurenine (Kyn) were found with dietary NaB administration, which showed significantly altered and closely correlated with the gut microbiota composition, demonstrating the complex interactions in the microbiome-gut-brain axis involved in the efficacy of dietary NaB therapy for alcoholic CNS lesions.

CONCLUSION

Dietary microbial metabolite butyrate supplementation ameliorates chronic alcoholic central nervous damage and improves related memory and cognitive functions through suppressing microglia-mediated neuroinflammation by GPR109A/PPAR-γ/TLR4-NF-κB signaling pathway and modulating microbiota-gut-brain axis.

Psychosocial factors and hippocampal subfields: The Medea-7T study

Specific subfields within the hippocampus have shown vulnerability to chronic stress, highlighting the importance of looking regionally within the hippocampus to understand the role of psychosocial factors in the development of neurodegenerative diseases. A systematic review on psychosocial factors and hippocampal subfield volumes was performed and showed inconsistent results, highlighting the need for future studies to explore this relationship. The current study aimed to explore the association of psychosocial factors with hippocampal (subfield) volumes, using high-field 7T MRI. Data were from the Memory Depression and Aging (Medea)-7T study, which included 333 participants without dementia. Hippocampal subfields were automatically segmented from T2-weighted images using ASHS software. Generalized linear models accounting for correlated outcomes were used to assess the association between subfields (i.e., entorhinal cortex, subiculum, Cornu Ammonis [CA]1, CA2, CA3, dentate gyrus, and tail) and each psychosocial factor (i.e., depressive symptoms, anxiety symptoms, childhood maltreatment, recent stressful life events, and social support), adjusted for age, sex, and intracranial volume. Neither depression nor anxiety was associated with specific hippocampal (subfield) volumes. A trend for lower total hippocampal volume was found in those reporting childhood maltreatment, and a trend for higher total hippocampal volume was found in those who experienced a recent stressful life event. Among subfields, low social support was associated with lower volume in the CA3 (B = -0.43, 95% CI: -0.72; -0.15). This study suggests possible differential effects among hippocampal (subfield) volumes and psychosocial factors.

Distinct multivariate structural brain profiles are related to variations in short- and long-delay memory consolidation across children and young adults

From early to middle childhood, brain regions that underlie memory consolidation undergo profound maturational changes. However, there is little empirical investigation that directly relates age-related differences in brain structural measures to memory consolidation processes. The present study examined memory consolidation of intentionally studied object-location associations after one night of sleep (short delay) and after two weeks (long delay) in normally developing 5-to-7-year-old children (n = 50) and young adults (n = 39). Behavioural differences in memory retention rate were related to structural brain measures. Our results showed that children, in comparison to young adults, retained correctly learnt object-location associations less robustly over short and long delay. Moreover, using partial least squares correlation method, a unique multivariate profile comprised of specific neocortical (prefrontal, parietal, and occipital), cerebellar, and hippocampal head and subfield structures in the body was found to be associated with variation in short-delay memory retention. A different multivariate profile comprised of a reduced set of brain structures, mainly consisting of neocortical (prefrontal, parietal, and occipital), hippocampal head, and selective hippocampal subfield structures (CA1-2 and subiculum) was associated with variation in long-delay memory retention. Taken together, the results suggest that multivariate structural pattern of unique sets of brain regions are related to variations in short- and long-delay memory consolidation across children and young adults.

Hair glucocorticoids are associated with childhood adversity, depressive symptoms and reduced global and lobar grey matter in Generation Scotland

Hypothalamic-pituitary-adrenal (HPA) axis dysregulation has been commonly reported in major depressive disorder (MDD), but with considerable heterogeneity of results; potentially due to the predominant use of acute measures of an inherently variable/phasic system. Chronic longer-term measures of HPA-axis activity have yet to be systematically examined in MDD, particularly in relation to brain phenotypes, and in the context of early-life/contemporaneous stress. Here, we utilise a temporally stable measure of cumulative HPA-axis function (hair glucocorticoids) to investigate associations between cortisol, cortisone and total glucocorticoids with concurrent measures of (i) lifetime-MDD case/control status and current symptom severity, (ii) early/current-life stress and (iii) structural neuroimaging phenotypes, in N = 993 individuals from Generation Scotland (mean age = 59.1 yrs). Increased levels of hair cortisol were significantly associated with reduced global and lobar brain volumes with reductions in the frontal, temporal and cingulate regions (βrange = -0.057 to -0.104, all PFDR < 0.05). Increased levels of hair cortisone were significantly associated with MDD (lifetime-MDD status, current symptoms, and severity; βrange = 0.071 to 0.115, all PFDR = < 0.05), with early-life adversity (β = 0.083, P = 0.017), and with reduced global and regional brain volumes (global: β = -0.059, P = 0.043; nucleus accumbens: β = -0.075, PFDR = 0.044). Associations with total glucocorticoids followed a similar pattern to the cortisol findings. In this large community-based sample, elevated glucocorticoids were significantly associated with MDD, with early, but not later-life stress, and with reduced global and regional brain phenotypes. These findings provide important foundations for future mechanistic studies to formally explore causal relationships between early adversity, chronic rather than acute measures of glucocorticoids, and neurobiological associations relevant to the aetiology of MDD.

Peer victimization and the association with hippocampal development and working memory in children with ADHD and typically-developing children

The symptoms of hyperactivity-impulsivity and inattention displayed by children with ADHD put them at risk of experiencing peer victimization. Hippocampal maturation, may reduce a child's vulnerability to the experience of peer victimization, as it has been associated with decreased ADHD symptomatology. Working memory is an important executive function in the formation and maintenance of social relationships, which is often impaired in ADHD. We aimed to evaluate the relationship between problem behaviours, peer victimization, hippocampal morphology, and working memory in children with and without ADHD. 218 typically-developing participants (50.5% male) and 232 participants diagnosed with ADHD (77.6% male) were recruited. The ADHD group was subdivided into inattentive (ADHD-I) or combined (ADHD-C) types. The Child Behavior Checklist measured problem behaviours and peer victimization. Children underwent Magnetic Resonance Imaging (MRI). Hippocampal subfield volumes were obtained using FreeSurfer. The Wechsler Intelligence Scale for Children-fifth edition measured working memory (WM). The ADHD-C group displayed significantly higher levels of problem behaviours and peer victimization (all, p < 0.001), compared to the other groups. Left Cornu Ammonis 3 (CA3) volume was a positive predictor of peer victimization (all, p < 0.013). Left CA3 volume was a positive predictor of WM and left Cornu Ammonis 4 (CA4) volume negatively predicted WM (all, p < 0.025). A cluster analysis revealed that children displaying symptoms of hyperactivity-impulsivity are the most at risk for peer victimization. Interventions focusing on minimizing peer victimization may aid in mitigating adverse downstream effects, and assist in promoting brain health and cognitive function.

Explaining socioeconomic disparities in health behaviours: A review of biopsychological pathways involving stress and inflammation

The purpose of this article was to explore how individuals' position in a socioeconomic hierarchy is related to health behaviours that are related to socioeconomic disparities in health. We identified research which shows that: (a) low socioeconomic status (SES) is associated with living in harsh environments, (b) harsh environments are related to increased levels of stress and inflammation, (c) stress and inflammation impact neural systems involved in self-control by sensitising the impulsive system and desensitising the reflective system, (d) the effects are inflated valuations of small immediate rewards and deflated valuations of larger delayed rewards, (e) these effects are observed as increased delay discounting, and (f) delay discounting is positively associated with practicing more unhealthy behaviours. The results are discussed within an adaptive evolutionary framework which lays out how the stress response system, and its interaction with the immune system and brain systems for decision-making and behaviours, provides the biopsychological mechanisms and regulatory shifts that make widespread conditional adaptability possible. Consequences for policy work, interventions, and future research are discussed.

Prenatal Exposure to High Cortisol Induces ADHD-like Behaviors with Delay in Spatial Cognitive Functions during the Post-weaning Period in Rats

High levels of cortisol in blood are frequently observed in patients with major depressive disorders and increased cortisol level induces depressivelike symptoms in animal models. However, it is still unclear whether maternal cortisol level during pregnancy is a critical factor resulting in neuropsychiatric disorders in offspring. In this study, we increased cortisol level in rats by repetitively injecting corticosterone subcutaneously (Corti. Mom, 20 mg/kg/day) during pregnancy and evaluated the behavioral patterns of their pups (Corti.Pups) via forced swimming (FS), open field (OF), elevated plus maze (EPM) and Morris water maze (MWM) tests during the immediate post-weaning period (postnatal day 21 to 25). In results, corticosterone significantly increased plasma cortisol levels in both Corti.Moms and Corti.Pups. Unlike depressive animal models, Corti.Pups showed higher hyperactive behaviors in the FS and OF tests than normal pups (Nor.Pups) born from rats (Nor.Moms) treated with saline. Furthermore, Corti.Pups spent more time and traveled longer distance in the open arms of EPM test, exhibiting higher extremity. These patterns were consistent with behavioral symptoms observed in animal models of attention deficit hyperactivity disorder (ADHD), which is characterized by hyperactivity, impulsivity, and inattention. Additionally, Corti.Pups swam longer and farther to escape in MWM test, showing cognitive declines associated with attention deficit. Our findings provide evidence that maternal cortisol level during pregnancy may affect the neuroendocrine regulation and the brain development of offspring, resulting in heterogeneous developmental brain disorders such as ADHD.