Brain corticosteroid receptor balance in health and disease

Key HPI axis receptors facilitate light adaptive behavior in larval zebrafish

The vertebrate stress response (SR) is mediated by the hypothalamic-pituitary-adrenal (HPA) axis and contributes to generating context appropriate physiological and behavioral changes. Although the HPA axis plays vital roles both in stressful and basal conditions, research has focused on the response under stress. To understand broader roles of the HPA axis in a changing environment, we characterized an adaptive behavior of larval zebrafish during ambient illumination changes. Genetic abrogation of glucocorticoid receptor (nr3c1) decreased basal locomotor activity in light and darkness. Some key HPI axis receptors (mc2r [ACTH receptor], nr3c1), but not nr3c2 (mineralocorticoid receptor), were required to adapt to light more efficiently but became dispensable when longer illumination was provided. Such light adaptation was more efficient in dimmer light. Our findings show that the HPI axis contributes to the SR, facilitating the phasic response and maintaining an adapted basal state, and that certain adaptations occur without HPI axis activity.

Inulae Flos has Anti-Depressive Effects by Suppressing Neuroinflammation and Recovering Dysfunction of HPA-axis

Depression is a debilitating mood disorder that causes persistent feelings of sadness, emptiness, and a loss of joy. However, the clinical efficacy of representative drugs for depression, such as selective serotonin reuptake inhibitors, remains controversial. Therefore, there is an urgent need for more effective therapies to treat depression. Neuroinflammation and the hypothalamic-pituitary-adrenal (HPA) axis are pivotal factors in depression. Inulae Flos (IF), the flower of Inula japonica Thunb, is known for its antioxidant and anti-inflammatory effects. This study explored whether IF alleviates depression in both in vitro and in vivo models. For in vitro studies, we treated BV2 and PC12 cells damaged by lipopolysaccharides or corticosterone (CORT) with IF to investigate the mechanisms of depression. For in vivo studies, C57BL/6 mice were exposed to chronic restraint stress and were administered IF at doses of 0, 100, and 300 mg/kg for 2 weeks. IF inhibited pro-inflammatory mediators, such as nitric oxide, inducible nitric oxide synthase, and interleukins in BV2 cells. Moreover, IF increased the viability of CORT-damaged PC12 cells by modulating protein kinase B, a mammalian target of the rapamycin pathway. Behavioral assessments demonstrated that IF reduced depression-like behaviors in mice. We found that IF reduced the activation of microglia and astrocytes, and regulated synapse plasticity in the mice brains. Furthermore, IF lowered elevated CORT levels in the plasma and restored glucocorticoid receptor expression in the hypothalamus. Collectively, these findings suggest that IF can alleviate depression by mitigating neuroinflammation and recovering dysfunction of the HPA-axis.

Effects of Corticosterone on Beta-Amyloid-Induced Cell Death in SH-SY5Y Cells

Alzheimer's disease (AD) is a neurodegenerative disease characterized by neuronal cell death and memory impairment. Corticosterone (CORT) is a glucocorticoid hormone produced by the hypothalamic-pituitary-adrenal axis in response to a stressful condition. Excessive stress and high CORT levels are known to cause neurotoxicity and aggravate various diseases, whereas mild stress and low CORT levels exert beneficial actions under pathophysiological conditions. However, the effects of mild stress on AD have not been clearly elucidated yet. In this study, the effects of low (3 and 30 nM) CORT concentration on Aβ25-35-induced neurotoxicity in SH-SY5Y cells and underlying molecular mechanisms have been investigated. Cytotoxicity caused by Aβ25-35 was significantly inhibited by the low concentration of CORT treatment in the cells. Furthermore, CORT pretreatment significantly reduced Aβ25-35-mediated pro-apoptotic signals, such as increased Bim/Bcl-2 ratio and caspase-3 cleavage. Moreover, low concentration of CORT treatment inhibited the Aβ25-35-induced cyclooxygenase-2 and pro-inflammatory cytokine expressions, including tumor necrosis factor-α and interleukin-1β. Aβ25-35 resulted in intracellular accumulation of reactive oxygen species and lipid peroxidation, which were effectively reduced by the low CORT concentration. As a molecular mechanism, low CORT concentration activated the nuclear factor-erythroid 2-related factor 2, a redox-sensitive transcription factor mediating cellular defense and upregulating the expression of antioxidant enzymes, such as NAD(P)H:quinone oxidoreductase, glutamylcysteine synthetase, and manganese superoxide dismutase. These findings suggest that low CORT concentration exerts protective actions against Aβ25-35-induced neurotoxicity and might be used to treat and/or prevent AD.

Stress-related cellular pathophysiology as a crosstalk risk factor for neurocognitive and psychiatric disorders

In this narrative review, we examine biological processes linking psychological stress and cognition, with a focus on how psychological stress can activate multiple neurobiological mechanisms that drive cognitive decline and behavioral change. First, we describe the general neurobiology of the stress response to define neurocognitive stress reactivity. Second, we review aspects of epigenetic regulation, synaptic transmission, sex hormones, photoperiodic plasticity, and psychoneuroimmunological processes that can contribute to cognitive decline and neuropsychiatric conditions. Third, we explain mechanistic processes linking the stress response and neuropathology. Fourth, we discuss molecular nuances such as an interplay between kinases and proteins, as well as differential role of sex hormones, that can increase vulnerability to cognitive and emotional dysregulation following stress. Finally, we explicate several testable hypotheses for stress, neurocognitive, and neuropsychiatric research. Together, this work highlights how stress processes alter neurophysiology on multiple levels to increase individuals' risk for neurocognitive and psychiatric disorders, and points toward novel therapeutic targets for mitigating these effects. The resulting models can thus advance dementia and mental health research, and translational neuroscience, with an eye toward clinical application in cognitive and behavioral neurology, and psychiatry.

Mechanisms associated with post-stroke depression and pharmacologic therapy

Stroke is one of the most common cerebrovascular diseases, which is the cause of long-term mental illness and physical disability, Post-stroke depression (PSD) is the most common neuropsychiatric complication after stroke, and its mechanisms are characterized by complexity, plurality, and diversity, which seriously affects the quality of survival and prognosis of patients. Studies have focused on and recognized neurotransmitter-based mechanisms and selective serotonin-reuptake inhibitors (SSRIs) can be used to treat PSD. Neuroinflammation, neuroendocrinology, neurotrophic factors, and the site of the stroke lesion may affect neurotransmitters. Thus the mechanisms of PSD have been increasingly studied. Pharmacological treatment mainly includes SSRIs, noradrenergic and specific serotonergic antidepressant (NaSSA), anti-inflammatory drugs, vitamin D, ect, which have been confirmed to have better efficacy by clinical studies. Currently, there is an increasing number of studies related to the mechanisms of PSD. However, the mechanisms and pharmacologic treatment of PSD is still unclear. In the future, in-depth research on the mechanisms and treatment of PSD is needed to provide a reference for the prevention and treatment of clinical PSD.

Glucocorticoid feedback paradox: a homage to Mary Dallman

As the end product of the hypothalamus-pituitary-adrenal (HPA) axis, the glucocorticoid hormones cortisol and corticosterone coordinate circadian activities, stress-coping, and adaptation to change. For this purpose, the hormone promotes energy metabolism and controls defense reactions in the body and brain. This life-sustaining action exerted by glucocorticoids occurs in concert with the autonomic nervous and immune systems, transmitters, growth factors/cytokines, and neuropeptides. The current contribution will focus on the glucocorticoid feedback paradox in the HPA-axis: the phenomenon that stress responsivity remains resilient if preceded by stress-induced secretion of glucocorticoid hormone, but not if this hormone is previously administered. Furthermore, in animal studies, the mixed progesterone/glucocorticoid antagonist RU486 or mifepristone switches to an apparent partial agonist upon repeated administration. To address these enigmas several interesting phenomena are highlighted. These include the conditional nature of the excitation/inhibition balance in feedback regulation, the role of glucose as a determinant of stress responsivity, and the potential of glucocorticoids in resetting the stress response system. The analysis of the feedback paradox provides also a golden opportunity to review the progress in understanding the role of glucocorticoid hormone in resilience and vulnerability during stress, the science that was burned deeply in Mary Dallman's emotions.

Maternal chewing alleviates prenatal stress-related neuroinflammation mediated by microglia in the hippocampus of the mouse offspring

PURPOSE

Prenatal stress affects the hippocampal structure and function in pups. Maternal chewing ameliorates hippocampus-dependent cognitive impairments induced by prenatal stress. In this study, we investigated hippocampal microglia-mediated neuroinflammation in pups of dams exposed to prenatal stress with or without chewing during gestation.

METHODS

Pregnant mice were randomly assigned to control, stress, and stress/chewing groups. Stress and stress/chewing animals were subjected to restraint stress for 45 min three times daily from gestation day 12 to parturition, and were given a wooden stick to chew during the stress period. Four-month-old male pups were intraperitoneally administered with lipopolysaccharide (LPS). Serum corticosterone levels were determined 24 h after administration. The expression levels of hippocampal inflammatory cytokines were measured, and the microglia were analyzed morphologically.

RESULTS

Prenatal stress increased serum corticosterone levels, induced hippocampal microglia priming, and facilitated the release of interleukin-1β and tumor necrosis factor-α in the offspring. LPS treatment significantly increased the effects of prenatal stress on serum corticosterone levels, hippocampal microglial activation, and hippocampal neuroinflammation. Maternal chewing significantly inhibited the increase in serum corticosterone levels, suppressed microglial overactivation, and normalized inflammatory cytokine levels under basal prenatal stress conditions as well as after LPS administration.

CONCLUSIONS

Our findings indicate that maternal chewing can alleviate the increase in corticosterone levels and inhibit hippocampal microglia-mediated neuroinflammation induced by LPS administration and prenatal stress in adult offspring.

Glucocorticoids and cognitive function: a walkthrough in endogenous and exogenous alterations

PURPOSE

The hypothalamic-pituitary-adrenal (HPA) axis exerts many actions on the central nervous system (CNS) aside from stress regulation. Glucocorticoids (GCs) play an important role in affecting several cognitive functions through the effects on both glucocorticoid (GR) and mineralocorticoid receptors (MR). In this review, we aim to unravel the spectrum of cognitive dysfunction secondary to derangement of circulating levels of endogenous and exogenous glucocorticoids.

METHODS

All relevant human prospective and retrospective studies published up to 2022 in PubMed reporting information on HPA disorders, GCs, and cognition were included.

RESULTS

Cognitive impairment is commonly found in GC-related disorders. The main brain areas affected are the hippocampus and pre-frontal cortex, with memory being the most affected domain. Disease duration, circadian rhythm disruption, circulating GCs levels, and unbalanced MR/GR activation are all risk factors for cognitive decline in these patients, albeit with conflicting data among different conditions. Lack of normalization of cognitive dysfunction after treatment is potentially attributable to GC-dependent structural brain alterations, which can persist even after long-term remission.

CONCLUSION

The recognition of cognitive deficits in patients with GC-related disorders is challenging, often delayed, or mistaken. Prompt recognition and treatment of underlying disease may be important to avoid a long-lasting impact on GC-sensitive areas of the brain. However, the resolution of hormonal imbalance is not always followed by complete recovery, suggesting irreversible adverse effects on the CNS, for which there are no specific treatments. Further studies are needed to find the mechanisms involved, which may eventually be targeted for treatment strategies.

The canonical HPA axis facilitates and maintains light adaptive behavior

The vertebrate stress response (SR) is mediated by the hypothalamic-pituitary-adrenal (HPA) axis and contributes to generating context appropriate physiological and behavioral changes. Although the HPA axis plays vital roles both in stressful and basal conditions, research has focused on the response under stress. To understand broader roles of the HPA axis in a changing environment, we characterized an adaptive behavior of larval zebrafish during ambient illumination changes. The glucocorticoid receptor (nr3c1) was necessary to maintain basal locomotor activity in light and darkness. The HPA axis was required to adapt to light more efficiently but became dispensable when longer illumination was provided. Light adaptation was more efficient in dimmer light and did not require the mineralocorticoid receptor (nr3c2). Our findings show that the HPA axis contributes to the SR at various stages, facilitating the phasic response and maintaining an adapted basal state, and that certain adaptations occur without HPA axis activity.

Irreversible Alterations of Susceptibility in Cushing's Disease: A Longitudinal QSM Study

OBJECTIVES

Chronic exposure to hypercortisolism is associated with accelerated aging and neurodegenerative diseases, while Cushing's disease (CD) is the most common form of endogenous hypercortisolism exposure. This study aimed to assess longitudinal susceptibility changes in CD using quantitative susceptibility mapping (QSM) before and after resolution of hypercortisolism.

METHODS

In this study, 24 CD patients and 24 healthy controls underwent magnetic resonance imaging (MRI) with QSM. All CD patients underwent MRI scans before and after the curative operation.

RESULTS

After resolution of hypercortisolism, irreversibly altered susceptibility values were found in the anterior cingulate cortex, frontal lobe, caudate, and red nucleus. These alterations were significantly correlated with the changes in gray matter/white matter volumes and clinical features. Additionally, decreased susceptibility was found in several regions in CD patients.

CONCLUSION

Chronic exposure to hypercortisolism may be related to susceptibility alterations and significantly correlated with altered brain volumes and clinical features. in CD patients. The decrease of susceptibility might suggest the involvement of the calcium deregulation in these alterations.

Oxytocin prevents dysregulation of the acute stress response and glucocorticoid-induced oxidative stress in chronically isolated prairie voles

Chronic social isolation can lead to dysregulation of many physiological and psychological processes, including the ability to respond to acute stressors. Previous work in our lab reported that six weeks of social isolation in prairie voles (Microtus ochrogaster) caused increased glucocorticoid levels, oxidative damage, telomere degradation and anhedonia, and that oxytocin treatment prevented all of these changes. Following these results, we investigated how chronic social isolation with and without oxytocin treatment affected glucocorticoid (CORT) and oxidative stress responses to an acute stressor, a 5-min resident-intruder (R-I) test at the end of the social isolation period. To investigate the effect of a brief acute stressor on CORT and oxidative stress, baseline blood samples were collected following six weeks of social isolation, 24-hrs before the R-I test. Two more blood samples were collected 15-min after the end of the R-I test, and again 25-min later to measure peak and recovery responses, respectively. Isolated animals had higher baseline, peak, recovery, and integrated levels of CORT and reactive oxygen metabolites (ROMs, a measure of oxidative stress), compared to animals that did not experience isolation. Importantly, oxytocin treatment throughout the isolation period prevented these elevations in CORT and ROMs. No significant changes were observed in total antioxidant capacity (TAC). Levels of CORT and ROMs at the peak and recovery time points were positively correlated. These data show that acute stress in chronically isolated prairie voles, then, is associated with increased glucocorticoid-induced oxidative stress (GiOS), and that oxytocin mitigates isolation-induced dysregulation of glucocorticoid and oxidative stress acute stress responses.

Differential effects of acute exercise on emotional memory in men and women

Exercise may change emotional memory, which is associated with the induction of mental disorders such as depression and anxiety. This effect of exercise may be influenced by exercise-induced cortisol release. Depending on sex, cortisol exerts differential effects on emotional memory consolidation. However, whether acute exercise and exercise-induced cortisol release have sex-dependent effects on emotional memory has not been established. Therefore, first, we aimed to determine the effects of acute exercise on emotional memory, separately for men and women, in a within-subjects design. Second, we aimed to examine whether the effects of acute exercise on emotional memory are related to the effects of exercise-induced cortisol release, separately for men and women. Sixteen healthy men and 15 healthy women were presented with positive and negative emotional images, followed by either rest or a vigorous-intensity cycling exercise condition using a within-subjects design on separate days. Salivary cortisol was measured before presenting the emotional images presentation and 20 min after each intervention. Emotional memory was assessed two days later. Vigorous-intensity exercise decreased emotional memory in women, whereas there was no change in men after rest or exercise. Cortisol levels increased after exercise intervention in both men and women, although there was no association between cortisol levels and emotional memory. These findings demonstrate that the effect of a single bout of vigorous-intensity exercise on emotional memory differs between men and women and is associated with decreased emotional memory in women.

A framework for testing pathways from prenatal stress-responsive hormones to cardiovascular disease risk

Cardiovascular disease (CVD) is a leading cause of death globally, with the prevalence projected to keep rising. Risk factors for adult CVD emerge at least as early as the prenatal period. Alterations in stress-responsive hormones in the prenatal period are hypothesized to contribute to CVD in adulthood, but little is known about relations between prenatal stress-responsive hormones and early precursors of CVD, such as cardiometabolic risk and health behaviors. The current review presents a theoretical model of the relation between prenatal stress-responsive hormones and adult CVD through cardiometabolic risk markers (e.g., rapid catch-up growth, high BMI/adiposity, high blood pressure, and altered blood glucose, lipids, and metabolic hormones) and health behaviors (e.g., substance use, poor sleep, poor diet and eating behaviors, and low physical activity levels). Emerging evidence in human and non-human animal literatures suggest that altered stress-responsive hormones during gestation predict higher cardiometabolic risk and poorer health behaviors in offspring. This review additionally highlights limitations of the current literature (e.g., lack of racial/ethnic diversity, lack of examination of sex differences), and discusses future directions for this promising area of research.

From Ligands to Behavioral Outcomes: Understanding the Role of Mineralocorticoid Receptors in Brain Function

Stress is a normal response to situational pressures or demands. Exposure to stress activates the hypothalamic-pituitary-adrenal (HPA) axis and leads to the release of corticosteroids, which act in the brain via two distinct receptors: mineralocorticoid receptors (MR) and glucocorticoid receptors (GR). Persistent HPA axis overactivation or dysregulation can disrupt an individual's homeostasis, thereby contributing to an increased risk for mental illness. On the other hand, successful coping with stressful events involves adaptive and cognitive processes in the brain that render individuals more resilient to similar stressors in the future. Here we review the role of the MR in these processes, starting with an overview of the physiological structure, ligand binding, and expression of MR, and further summarizing its role in the brain, its relevance to psychiatric disorders, and related rodent studies. Given the central role of MR in cognitive and emotional functioning, and its importance as a target for promoting resilience, future research should investigate how MR modulation can be used to alleviate disturbances in emotion and behavior, as well as cognitive impairment, in patients with stress-related psychiatric disorders.

Prenatal stress modulates HPA axis homeostasis of offspring through dentate TERT independently of glucocorticoids receptor

In response to stressful events, the hypothalamic-pituitary-adrenal (HPA) axis is activated, and consequently glucocorticoids are released by the adrenal gland into the blood circulation. A large body of research has illustrated that excessive glucocorticoids in the hippocampus exerts negative feedback regulation of the HPA axis through glucocorticoid receptor (GR), which is critical for the homeostasis of the HPA axis. Maternal prenatal stress causes dysfunction of the HPA axis feedback mechanism in their offspring in adulthood. Here we report that telomerase reverse transcriptase (TERT) gene knockout causes hyperactivity of the HPA axis without hippocampal GR deficiency. We found that the level of TERT in the dentate gyrus (DG) of the hippocampus during the developmental stage determines the responses of the HPA axis to stressful events in adulthood through modulating the excitability of the dentate granular cells (DGCs) rather than the expression of GR. Our study also suggests that the prenatal high level of glucocorticoids exposure-induced hypomethylation at Chr13:73764526 in the first exon of mouse Tert gene accounted for TERT deficiency in the DG and HPA axis abnormality in the adult offspring. This study reveals a novel GR-independent mechanism underlying prenatal stress-associated HPA axis impairment, providing a new angle for understanding the mechanisms for maintaining HPA axis homeostasis.

Mineralocorticoid receptor agonist aldosterone rescues hippocampal neural stem cell proliferation defects and improves postoperative cognitive function in aged mice

OBJECTIVES

Hippocampal neurogenesis is closely related to learning and memory, and hippocampal neurogenesis disorders are involved in the development of many neurodegenerative diseases. Mineralocorticoid receptor (MR) plays a vital role in regulating stress response, neuroendocrine and cognitive functions, and is involved in regulating the integrity and stability of neural networks. However, the potential role of MR in the pathogenesis of postoperative cognitive dysfunction (POCD) is unclear. Therefore, this study evaluated the effect and mechanism of MR activation on postoperative hippocampal neurogenesis and cognitive function in aged mice.

METHODS

18-month-old male Kunming mice were randomly divided into Control group (C group), Surgery group (S group), Surgery+ Aldosterone group (S+Aldo group), Surgery + Wortmannin group (S+Wort group), Surgery + Aldosterone + Wortmannin group (S+Aldo+Wort group). Laparotomy was used to establish an animal model of postoperative cognitive dysfunction. After surgery, mice were intraperitoneally injected with aldosterone (100 ug/kg,150 ug/kg,200 ug/kg) and / or wortmannin (1 mg/kg); One day before the sacrifice, mice were injected intraperitoneally with BrdU (100 mg / kg / time, 3 times in total). Mice were subjected to Morris water maze and field tests at 1, 3, 7, and 14 days after surgery. Immunofluorescence was used to detect the number of BrdU +, Nestin +, BrdU/Nestin + positive cells in the hippocampal dentate gyrus of mice at 1, 3, 7 and 14 days after surgery. Western-blot was used to detect PI3K/Akt/GSK-3β signaling pathway related proteins Akt, p-Akt, GSK-3β, P-GSK-3β expression.

RESULTS

Stress impairs the performance of aged mice in water maze and open field tests, reduces the number of BrdU/Nestin+ cells in the hippocampal dentate gyrus, and inhibits the phosphorylation of Akt and GSK-3β proteins in the hippocampus. Aldosterone treatment promotes P-Akt, P-GSK-3β protein expression and hippocampal neural stem cell proliferation, and improves postoperative cognitive dysfunction. However, wortmannin treatment significantly reversed these effects of aldosterone.

CONCLUSIONS

The mineralocorticoid receptor agonist aldosterone promotes the proliferation of hippocampal neural stem cells and improves cognitive dysfunction in aged mice after surgery, and the mechanism may be related to activation of PI3K/Akt/GSK-3β signaling.

Prior parental experience attenuates hormonal stress responses and alters hippocampal glucocorticoid receptors in biparental rock doves

In the face of challenges, animals must balance investments in reproductive effort versus their own survival. Physiologically, this trade-off may be mediated by glucocorticoid release by the hypothalamic-pituitary-adrenal axis and prolactin release from the pituitary to maintain parental care. The degree to which animals react to and recover from stressors likely affects maintenance of parental behavior and, ultimately, fitness. However, less is known about how gaining parental experience may alter hormonal stress responses and their underlying neuroendocrine mechanisms. To address this gap, we measured the corticosterone (CORT) and prolactin (PRL) stress response in individuals of both sexes of the biparental rock dove (Columba livia) that had never raised chicks versus birds that had fledged at least one chick. We measured both CORT and PRL at baseline and after an acute stressor (30 min restraint). We also measured negative feedback ability by administering dexamethasone, a synthetic glucocorticoid that suppresses CORT release, and measured CORT and PRL after 60 min. All hormones were measured when birds were not actively nesting to assess whether effects of parental experience extend beyond the breeding bout. Experienced birds had lower stress-induced and negative-feedback CORT, and higher stress-induced PRL than inexperienced birds. In a separate experiment, we measured glucocorticoid receptor subtype expression in the hippocampus, a key site of negative feedback regulation. Experienced birds showed higher glucocorticoid receptor expression than inexperienced controls, which may mediate their ability to attenuate CORT release. Together, these results shed light on potential mechanisms by which gaining experience may improve parental performance and fitness.

Developmental Programming by Perinatal Glucocorticoids

Early-life environmental factors can have persistent effects on physiological functions by altering developmental procedures in various organisms. Recent experimental and epidemiological studies now further support the idea that developmental programming is also present in mammals, including humans, influencing long-term health. Although the mechanism of programming is still largely under investigation, the role of endocrine glucocorticoids in developmental programming is gaining interest. Studies found that perinatal glucocorticoids have a persistent effect on multiple functions of the body, including metabolic, behavioral, and immune functions, in adulthood. Several mechanisms have been proposed to play a role in long-term programming. In this review, recent findings on this topic are summarized and the potential biological rationale behind this phenomenon is discussed.

Early-life maternal deprivation affects the mother-offspring relationship in domestic pigs, as well as the neuroendocrine development and coping behavior of piglets

Early-life adversity may have programming effects on the psychological and physiological development of offspring. Domestic pigs (Sus scrofa) are an excellent model species for studying these effects because of their many physiological similarities to humans. Piglets from 10 sows were subjected to daily 2-h maternal deprivation on postnatal days (PND) 2–15 alone (DA) or in a group of littermates (DG). Control piglets (C) from 10 sows stayed with their mothers. Mother-offspring interaction, milk oxytocin, and cortisol were analyzed. An open-field/novel-object (OF/NO) test was performed with piglets on PNDs 16 and 40. Plasma cortisol and immune parameters were determined on PND 5 and 16. Two piglets from each group and sow were sacrificed on PND 20 and stress-related gene expression in the limbic system and prefrontal cortex (PFC), as well as splenic lymphocyte proliferative abilities, were examined. The milk cortisol of sows increased during the first separation of mother and offspring on the second day of lactation, whereas milk oxytocin did not change. The increase in cortisol by the OF/NO test on PND 16 was greater in C piglets than in DA and DG ones. DA piglets showed less agitated behavior than DG and C piglets in the OF/NO test at PND 16, but appeared more fearful. On PND 40, DA piglets showed more arousal than DG and C piglets in the OF/NO test. Neither plasma IgA nor N/L ratios in blood nor mitogen-induced proliferation of spleen lymphocytes were affected by deprivation. We found a higher mRNA expression of CRHR1 in the hypothalamus and a higher expression of MR in the hippocampus in DA piglets than in DG ones. The expression of GR, MR, and CRHR1 genes in the PFC was reduced by maternal deprivation, however, the expression of arginine vasopressin and oxytocin receptors was not affected. Repeated maternal deprivation induces sustained effects on stress reactivity and behavior of domestic piglets. Some of these effects were buffered by the presence of littermates. In addition, we found sex-specific differences in behavior and gene expression.

The infralimbic mineralocorticoid blockage prevents the stress-induced impairment of aversive memory extinction in rats

Individuals deal with adversity and return to a normal lifestyle when adversity ends. Nevertheless, in specific cases, traumas may be preceded by memory distortions in stress-related malaises, and memory extinction impairment is strictly associated with the symptoms of post-traumatic stress disorder. Glucocorticoids (GCs), the central stress mediator, target mineralocorticoid (MR) and glucocorticoid (GR) receptors and coordinate stress responses. Despite MRs being present in brain regions essential to cognition, emotions, and initial stress processing, such as the medial prefrontal cortex (mPFC), most studies attempt to elucidate the stress-induced deleterious actions of GCs via GR. Therefore, it is necessary to understand the relationship between stress, infralimbic mPFC (IL), and memory and how MR-mediated intracellular signaling influences this relationship and modulates memory extinction. We observed that acutely restraint-stressed male Wistar rats showed high corticosterone (CORT) levels, and previous intra-IL-spironolactone administration (a selective MR antagonist) decreased it 60 min after the stress started. Intra-IL-CORT118335, a novel mixed MR/GR selective modulator, increased CORT throughout stress exposure. Ten days after stress, all rats increased freezing in the memory retrieval test and acquired the aversive contextual memory. During the extinction test, intra-IL injection of spironolactone, but not CORT118335, prevented the stress-impaired memory extinction, suggesting that the IL-MR activity controls CORT concentration, and it is crucial to the establishment of late extinction impairment. Also, the concomitant GR full activation overrode MR blockage. It increased CORT levels leading to the stress-induced extinction memory impairment, reinforcing that the MR/GR balance is crucial to predicting stress-induced behavioral outcomes.

A functional role of meningeal lymphatics in sex difference of stress susceptibility in mice

Major depressive disorder is one of the most common mental health conditions. Meningeal lymphatics are essential for drainage of molecules in the cerebrospinal fluid to the peripheral immune system. Their potential role in depression-like behaviour has not been investigated. Here, we show in mice, sub-chronic variable stress as a model of depression-like behaviour impairs meningeal lymphatics in females but not in males. Manipulations of meningeal lymphatics regulate the sex difference in the susceptibility to stress-induced depression- and anxiety-like behaviors in mice, as well as alterations of the medial prefrontal cortex and the ventral tegmental area, brain regions critical for emotional regulation. Together, our findings suggest meningeal lymphatic impairment contributes to susceptibility to stress in mice, and that restoration of the meningeal lymphatics might have potential for modulation of depression-like behaviour.

Long lasting anxiety following early life stress is dependent on glucocorticoid signaling in zebrafish

Chronic adversity in early childhood is associated with increased anxiety and a propensity for substance abuse later in adulthood, yet the effects of early life stress (ELS) on brain development remain poorly understood. The zebrafish, Danio rerio, is a powerful model for studying neurodevelopment and stress. Here, we describe a zebrafish model of ELS and identify a role for glucocorticoid signaling during a critical window in development that leads to long-term changes in brain function. Larval fish subjected to chronic stress in early development exhibited increased anxiety-like behavior and elevated glucocorticoid levels later in life. Increased stress-like behavior was only observed when fish were subjected to ELS within a precise time window in early development, revealing a temporal critical window of sensitivity. Moreover, enhanced anxiety-like behavior only emerges after two months post-ELS, revealing a developmentally specified delay in the effects of ELS. ELS leads to increased levels of baseline cortisol, and resulted in a dysregulation of cortisol receptors' mRNA expression, suggesting long-term effects on cortisol signaling. Together, these findings reveal a 'critical window' for ELS to affect developmental reprogramming of the glucocorticoid receptor pathway, resulting in chronic elevated stress.

Prolonged Extreme Cold Water Diving and the Acute Stress Response During Military Dive Training

Introduction: Cold water exposure poses a unique physiological challenge to the human body. Normally, water submersion increases activation of parasympathetic tone to induce bradycardia in order to compensate for hemodynamic shifts and reduce oxygen consumption by peripheral tissues. However, elevated stress, such as that which may occur due to prolonged cold exposure, may shift the sympatho-vagal balance towards sympathetic activation which may potentially negate the dive reflex and impact thermoregulation.

Objective: To quantify the acute stress response during prolonged extreme cold water diving and to determine the influence of acute stress on thermoregulation.

Materials and Methods: Twenty-one (n = 21) subjects tasked with cold water dive training participated. Divers donned standard diving equipment and fully submerged to a depth of ≈20 feet, in a pool chilled to 4°C, for a 9-h training exercise. Pre- and post-training measures included: core and skin temperature; salivary alpha amylase (AA), cortisol (CORT), osteocalcin (OCN), testosterone (TEST) and dehydroepiandosterone (DHEA); body weight; blood glucose, lactate, and ketones.

Results: Core, skin, and extremity temperature decreased (p < 0.001) over the 9-h dive; however, core temperature was maintained above the clinical threshold for hypothermia and was not correlated to body size (p = 0.595). There was a significant increase in AA (p < 0.001) and OCN (p = 0.021) and a significant decrease in TEST (p = 0.003) over the duration of the dive. An indirect correlation between changes in cortisol concentrations and changes in foot temperature (ρ = -0.5,p = 0.042) were observed. There was a significant positive correlation between baseline OCN and change in hand temperature (ρ = 0.66, p = 0.044) and significant indirect correlation between changes in OCN concentrations and changes in hand temperature (ρ = -0.59, p = 0.043).

Conclusion: These data suggest that long-duration, cold water diving initiates a stress response—as measurable by salivary stress biomarkers—and that peripheral skin temperature decreases over the course of these dives. Cumulatively, these data suggest that there is a relationship between the acute stress response and peripheral thermoregulation.

Teachers' physiological and self-reported stress, teaching practices and students' learning outcomes in Grade 1

BACKGROUND

Teachers' self-reported stress is related to the quality of teacher-student interactions and students' learning outcomes. However, it is unclear if teachers' physiological stress is related to child-centred teaching practices in the classroom and whether teaching practices mediate the link between teachers' stress and students' learning outcomes.

AIMS

We studied the effect of teachers' physiological stress and self-reported stress on their teaching practices and thereby on students' learning outcomes in math.

SAMPLE

A total of 53 classroom teachers and 866 Grade 1 students participated in the study.

METHODS

Salivary cortisol in the middle of the school day and cortisol slope from morning peak to evening were used as indicators of teachers' physiological stress, in addition to self-reported teaching-related stress. Teaching practices were observed with the ECCOM instrument. Students' math skills controlled for gender and previous skills were used as a measure of learning outcomes. Data were analysed with a two-level SEM.

RESULTS

Teachers' physiological stress did not have an effect on teaching practices or students' math skills. Teachers reporting less stress used relatively more child-centred teaching practices compared with teacher-directed ones. These practices had a marginal effect on classroom-level differences in the gain of students' math skills in Grade 1. There was neither a direct nor indirect effect from teachers' stress on students' math skills. Altogether, our model explained 77% of classroom-level variance in math skills.

CONCLUSIONS

Teachers' self-reported stress has an effect on their teaching practices, which, in turn, have a marginal effect on students' learning outcomes.

Pharmacological Implications of Adjusting Abnormal Fear Memory: Towards the Treatment of Post-Traumatic Stress Disorder

Post-traumatic stress disorder (PTSD) is a unique clinical mental abnormality presenting a cluster of symptoms in which patients primarily experience flashbacks, nightmares and uncontrollable thoughts about the event that triggered their PTSD. Patients with PTSD may also have comorbid depression and anxiety in an intractable and long-term course, which makes establishing a comprehensive treatment plan difficult and complicated. The present article reviews current pharmacological manipulations for adjusting abnormal fear memory. The roles of the central monoaminergic systems (including serotonin, norepinephrine and dopamine) within the fear circuit areas and the involvement of the hypothalamic-pituitary-adrenal (HPA) axis and glucocorticoid receptor (GR) are explored based on attempts to integrate current clinical and preclinical basic studies. In this review, we explain how these therapeutic paradigms function based on their connections to stages of the abnormal fear memory process from condition to extinction. This may provide useful translational interpretations for clinicians to manage PTSD.

Integrative Brain Dynamics in Childhood Bullying Victimization: Cognitive and Emotional Convergence Associated With Stress Psychopathology

Bullying victimization is a form of psychological stress that is associated with poor outcomes in the areas of mental health and learning. Although the emotional maladjustment and memory impairment following interpersonal stress are well documented, the mechanisms of complex cerebral dysfunctions have neither been outlined nor studied in depth in the context of childhood bullying victimization. As a contribution to the cross-disciplinary field of developmental psychology and neuroscience, we review the neuropathophysiology of early life stress, as well as general psychological stress to synthesize the data and clarify the versatile dynamics within neuronal networks linked to bullying victimization. The stress-induced neuropsychological cascade and associated cerebral networks with a focus on cognitive and emotional convergence are described. The main findings are that stress-evoked neuroendocrine reactivity relates to neuromodulation and limbic dysregulation that hinder emotion processing and executive functioning such as semantic cognition, cognitive flexibility, and learning. Developmental aspects and interacting neural mechanisms linked to distressed cognitive and emotional processing are pinpointed and potential theory-of-mind nuances in targets of bullying are presented. The results show that childhood stress psychopathology is associated with a complex interplay where the major role belongs to, but is not limited to, the amygdala, fusiform gyrus, insula, striatum, and prefrontal cortex. This interplay contributes to the sensitivity toward facial expressions, poor cognitive reasoning, and distress that affect behavioral modulation and emotion regulation. We integrate the data on major brain dynamics in stress neuroactivity that can be associated with childhood psychopathology to help inform future studies that are focused on the treatment and prevention of psychiatric disorders and learning problems in bullied children and adolescents.

Primary Aldosteronism and Resistant Hypertension: A Pathophysiological Insight

Primary aldosteronism (PA) is a pathological condition characterized by an excessive aldosterone secretion; once thought to be rare, PA is now recognized as the most common cause of secondary hypertension. Its prevalence increases with the severity of hypertension, reaching up to 29.1% in patients with resistant hypertension (RH). Both PA and RH are "high-risk phenotypes", associated with increased cardiovascular morbidity and mortality compared to non-PA and non-RH patients. Aldosterone excess, as occurs in PA, can contribute to the development of a RH phenotype through several mechanisms. First, inappropriate aldosterone levels with respect to the hydro-electrolytic status of the individual can cause salt retention and volume expansion by inducing sodium and water reabsorption in the kidney. Moreover, a growing body of evidence has highlighted the detrimental consequences of "non-classical" effects of aldosterone in several target tissues. Aldosterone-induced vascular remodeling, sympathetic overactivity, insulin resistance, and adipose tissue dysfunction can further contribute to the worsening of arterial hypertension and to the development of drug-resistance. In addition, the pro-oxidative, pro-fibrotic, and pro-inflammatory effects of aldosterone may aggravate end-organ damage, thereby perpetuating a vicious cycle that eventually leads to a more severe hypertensive phenotype. Finally, neither the pathophysiological mechanisms mediating aldosterone-driven blood pressure rise, nor those mediating aldosterone-driven end-organ damage, are specifically blocked by standard first-line anti-hypertensive drugs, which might further account for the drug-resistant phenotype that frequently characterizes PA patients.

Hippocampal volume, FKBP5 genetic risk alleles, and childhood trauma interact to increase vulnerability to chronic multisite musculoskeletal pain

Chronic multisite musculoskeletal pain (CMP) is common and highly morbid. However, vulnerability factors for CMP are poorly understood. Previous studies have independently shown that both small hippocampal brain volume and genetic risk alleles in a key stress system gene, FKBP5, increase vulnerability for chronic pain. However, little is known regarding the relationship between these factors and CMP. Here we tested the hypothesis that both small hippocampal brain volume and FKBP5 genetic risk, assessed using the tagging risk variant, FKBP5rs3800373, increase vulnerability for CMP. We used participant data from 36,822 individuals with available genetic, neuroimaging, and chronic pain data in the UK Biobank study. Although no main effects were observed, the interaction between FKBP5 genetic risk and right hippocampal volume was associated with CMP severity (β = -0.020, p_raw = 0.002, p_adj = 0.01). In secondary analyses, severity of childhood trauma further moderated the relationship between FKBP5 genetic risk, right hippocampal brain volume, and CMP (β = -0.081, p = 0.016). This study provides novel evidence that both FKBP5 genetic risk and childhood trauma moderate the relationship between right hippocampal brain volume and CMP. The data increases our understanding of vulnerability factors for CMP and builds a foundation for further work assessing causal relationships that might drive CMP development.

Heat-Stress Preconditioning Attenuates Behavioral Responses to Psychological Stress: The Role of HSP-70 in Modulating Stress Responses

Exposure to high ambient temperature is a stressor that influences both biological and behavioral functions and has been previously shown to have an extensive impact on brain structure and function. Physiological, cellular and behavioral responses to heat-stress (HS) (40-41 °C, 2 h) were evaluated in adult male Sprague-Dawley rats. The effect of HS exposure before predator-scent stress (PSS) exposure (i.e., HS preconditioning) was examined. Finally, a possible mechanism of HS-preconditioning to PSS was investigated. Immunohistochemical analyses of chosen cellular markers were performed in the hippocampus and in the hypothalamic paraventricular nucleus (PVN). Plasma corticosterone levels were evaluated, and the behavioral assessment included the elevated plus-maze (EPM) and the acoustic startle response (ASR) paradigms. Endogenous levels of heat shock protein (HSP)-70 were manipulated using an amino acid (L-glutamine) and a pharmacological agent (Doxazosin). A single exposure to an acute HS resulted in decreased body mass (BM), increased body temperature and increased corticosterone levels. Additionally, extensive cellular, but not behavioral changes were noted. HS-preconditioning provided behavioral resiliency to anxiety-like behavior associated with PSS, possibly through the induction of HSP-70. Targeting of HSP-70 is an attractive strategy for stress-related psychopathology treatment.

Corticosterone induces discrete epigenetic signatures in the dorsal and ventral hippocampus that depend upon sex and genotype: focus on methylated Nr3c1 gene

The genomic effects of circulating glucocorticoids are particularly relevant in cortico-limbic structures, which express a high concentration of steroid hormone receptors. To date, no studies have investigated genomic differences in hippocampal subregions, namely the dorsal (dHPC) and ventral (vHPC) hippocampus, in preclinical models treated with exogenous glucocorticoids. Chronic oral corticosterone (CORT) in mouse is a pharmacological approach that disrupts the activity of the hypothalamic-pituitary-adrenal axis, increases affective behavior, and induces genomic changes after stress in the HPC of wildtype (WT) mice and mice heterozygous for the gene coding for brain-derived neurotrophic factor Val66Met (hMet), a variant associated with genetic susceptibility to stress. Using RNA-sequencing, we investigated the genomic signatures of oral CORT in the dHPC and vHPC of WT and hMet male and female mice, and examined sex and genotype differences in response to oral CORT. Males under CORT showed lower glycemia and increased anxiety- and depression-like behavior compared to females that showed instead opposite affective behavior in response to CORT. Rank-rank-hypergeometric overlap (RRHO) was used to identify genes from a continuous gradient of significancy that were concordant across groups. RRHO showed that CORT-induced differentially expressed genes (DEGs) in WT mice and hMet mice converged in the dHPC of males and females, while in the vHPC, DEGs converged in males and diverged in females. The vHPC showed a higher number of DEGs compared to the dHPC and exhibited sex differences related to glucocorticoid receptor (GR)-binding genes and epigenetic modifiers. Methyl-DNA-immunoprecipitation in the vHPC revealed differential methylation of the exons 1_C and 1_F of the GR gene (Nr3c1) in hMet females. Together, we report behavioral and endocrinological sex differences in response to CORT, as well as epigenetic signatures that i) differ in the dHPC and vHPC,ii) are distinct in males and females, and iii) implicate differential methylation of Nr3c1 selectively in hMet females.

Stachyose Alleviates Corticosterone-Induced Long-Term Potentiation Impairment via the Gut–Brain Axis

Stress can induce learning and memory impairment; corticosterone is often used to study the effects and mechanisms of stress in animal models. Long-term potentiation (LTP) has been widely used for tackling the mechanisms of memory. Liuwei Dihuang decoction-active fraction combination (LW-AFC) can improve stress-induced LTP and cognition impairment; stachyose is an oligosaccharide in LW-AFC. The effects and mechanisms of stachyose on stress are unknown. In this study, stachyose showed protective effects against LTP impairment by corticosterone in vivo only via intragastric administration for 7 consecutive days, but there was little effect even after direct intracerebroventricular injection; the protective effect of stachyose could be canceled by non-absorbable antibiotics (ATB) which disturbed gut flora. 16S rRNA sequencing, alpha diversity, and principal coordinate analysis (PCoA) revealed that the gut flora in corticosterone-treated mice was disturbed and stachyose could improve corticosterone-induced gut flora disturbance. Bacteroidetes were decreased and Deferribacteres were increased significantly in corticosterone-treated mice, and stachyose restored Bacteroidetes and Deferribacteres to the normal level. D-serine, a coactivator of NMDA receptors, plays an important role in synaptic plasticity and cognition. Here, corticosterone had little effect on the content of D-serine and L-serine (the precursor of D-serine), but it reduced the D-serine release-related proteins, Na⁺-independent alanine–serine–cysteine transporter-1 (ASC-1), and vesicle-associated membrane protein 2 (VAMP2) significantly in hippocampus; stachyose significantly increased ASC-1 and VAMP2 in corticosterone-treated mice, and ATB blocked stachyose’s effects on ASC-1 and VAMP2. NMDA receptors co-agonists L-serine, D-serine, and glycine significantly improved LTP impairment by corticosterone. These results indicated that stachyose might indirectly increase D-serine release through the gut–brain axis to improve LTP impairment by corticosterone in the hippocampus in vivo.

Interdisciplinary Approach to Biological and Health Implications in Selected Professional Competences

Everyday life’s hygiene and professional realities, especially in economically developed countries, indicate the need to modify the standards of pro-health programs as well as modern hygiene and work ergonomics programs. These observations are based on the problem of premature death caused by civilization diseases. The biological mechanisms associated with financial risk susceptibility are well described, but there is little data explaining the biological basis of neuroaccounting. Therefore, the aim of the study was to present relationships between personality traits, cognitive competences and biological factors shaping behavioral conditions in a multidisciplinary aspect. This critical review paper is an attempt to compile biological and psychological factors influencing the development of professional competences, especially decent in the area of accounting and finance. We analyzed existing literature from wide range of scientific disciplines (including economics, psychology, behavioral genetics) to create background to pursuit multidisciplinary research models in the field of neuroaccounting. This would help in pointing the best genetically based behavioral profile of future successful financial and accounting specialists.

A Reasonable Officer: Examining the Relationships Among Stress, Training, and Performance in a Highly Realistic Lethal Force Scenario

Under conditions of physiological stress, officers are sometimes required to make split-second life-or-death decisions, where deficits in performance can have tragic outcomes, including serious injury or death and strained police-community relations. The current study assessed the performance of 122 active-duty police officers during a realistic lethal force scenario to examine whether performance was affected by the officer's level of operational skills training, years of police service, and stress reactivity. Results demonstrated that the scenario produced elevated heart rates (i.e., 150 beats per minute), as well as perceptual and cognitive distortions, such as tunnel vision, commensurate with those observed in naturalistic use of force encounters. The average performance rating from the scenario was 59%, with 27% of participants making at least one lethal force error. Elevated stress reactivity was a predictor of poorer performance and increased lethal force errors. Level of training and years of police service had differential and complex effects on both performance and lethal force errors. Our results illustrate the need to critically reflect on police training practices and continue to make evidence-based improvements to training. The findings also highlight that while training may significantly improve outcomes, flawless performance is likely not probable, given the limits of human performance under stress. Implications for the objective reasonableness standard, which is used to assess the appropriateness of force in courts of law, are discussed.

Gut-Brain Axis: Possible Role of Gut Microbiota in Perioperative Neurocognitive Disorders

Aging is becoming a severe social phenomenon globally, and the improvements in health care and increased health awareness among the elderly have led to a dramatic increase in the number of surgical procedures. Because of the degenerative changes in the brain structure and function in the elderly, the incidence of perioperative neurocognitive disorders (PND) is much higher in elderly patients than in young people following anesthesia/surgery. PND is attracting more and more attention, though the exact mechanisms remain unknown. A growing body of evidence has shown that the gut microbiota is likely involved. Recent studies have indicated that the gut microbiota may affect postoperative cognitive function via the gut-brain axis. Nonetheless, understanding of the mechanistic associations between the gut microbiota and the brain during PND progression remains very limited. In this review, we begin by providing an overview of the latest progress concerning the gut-brain axis and PND, and then we summarize the influence of perioperative factors on the gut microbiota. Next, we review the literature on the relationship between gut microbiota and PND and discuss how gut microbiota affects cognitive function during the perioperative period. Finally, we explore effective early interventions for PND to provide new ideas for related clinical research.

Coordinated Action of Corticotropin-Releasing Hormone and Cortisol Shapes the Acute Stress-Induced Behavioural Response in Zebrafish

INTRODUCTION

The stress response mediated by the hypothalamus-pituitary-adrenal (HPA) axis activation is highly conserved in vertebrates. Hyperactivity is one such established acute stress response, and corticotropin-releasing hormone (CRH), the primary step in HPA activation, signalling has been implicated in this stressor-mediated behaviour. However, whether CRH mediates the acute behavioural effects either alone or in conjunction with glucocorticoids (GCs) are far from clear. We hypothesized that the CRH receptor 1 (CRHR1)-mediated rise in GCs post-stress is necessary for the initiation and maintenance of the acute stress-related behaviour.

METHODS

We first generated zebrafish (Danio rerio) with a mutation in the CRHR1 gene (CRHR1-KO) to assess the function of CRH. The behavioural readout utilized for this study was the locomotor activity of larval zebrafish in response to an acute light exposure, a protocol that freezes the larvae in response to the light stimulus. To test whether cortisol signalling is involved in the stress-mediated hyperactivity, we treated wildtype fish with metyrapone (MET), an inhibitor of 11β-hydroxylase, to suppress cortisol production. The temporal role for cortisol signalling in the stress-related hyperactivity was tested using the glucocorticoid receptor knockout (GRKO) and mineralocorticoid receptor knockout (MRKO) zebrafish mutants.

RESULTS

CRHR1-KO larvae did not increase cortisol, the principal GC in teleosts, post-stress, confirming a functional knockout. An acute stress resulted in the hyperactivity of the larvae in light at 15, 60, and 240 min post-stress, and this was absent in CRHR1-KO larvae. Addition of MET effectively blocked the attendant rise in cortisol post-stress; however, the stress-mediated hyperactivity was inhibited only at 60 and 240 min but not at 15 min post-stress. Addition of human CRH peptide caused hyperactivity at 15 min, and this response was also abolished in the CRHR1-KO mutants. The stress-induced hyperactivity was absent in the MRKO fish, while GRKO mutants showed transient effects.

CONCLUSIONS

The results suggest that the stress-induced hyperactivity is induced by the CRH/CRHR1 system, while the temporal activation of cortisol production and the associated GR/MR signalling is essential for prolonging the stressor-induced hyperactivity. This study underscores the importance of systems-level analysis to assess stress responsivity.

Family environment and development in children adopted from institutionalized care

BACKGROUND

After adoption, children exposed to institutionalized care show significant improvement, but incomplete recovery of growth and developmental milestones. There is a paucity of data regarding risk and protective factors in children adopted from institutionalized care. This prospective study followed children recently adopted from institutionalized care to investigate the relationship between family environment, executive function, and behavioral outcomes.

METHODS

Anthropometric measurements, physical examination, endocrine and bone age evaluations, neurocognitive testing, and behavioral questionnaires were evaluated over a 2-year period with children adopted from institutionalized care and non-adopted controls.

RESULTS

Adopted children had significant deficits in growth, cognitive, and developmental measurements compared to controls that improved; however, residual deficits remained. Family cohesiveness and expressiveness were protective influences, associated with less behavioral problems, while family conflict and greater emphasis on rules were associated with greater risk for executive dysfunction.

CONCLUSIONS

Our data suggest that a cohesive and expressive family environment moderated the effect of pre-adoption adversity on cognitive and behavioral development in toddlers, while family conflict and greater emphasis on rules were associated with greater risk for executive dysfunction. Early assessment of child temperament and parenting context may serve to optimize the fit between parenting style, family environment, and the child's development.

IMPACT

Children who experience institutionalized care are at increased risk for significant deficits in developmental, cognitive, and social functioning associated with a disruption in the development of the prefrontal cortex. Aspects of the family caregiving environment moderate the effect of early life social deprivation in children. Family cohesiveness and expressiveness were protective influences, while family conflict and greater emphasis on rules were associated with a greater risk for executive dysfunction problems. This study should be viewed as preliminary data to be referenced by larger studies investigating developmental and behavioral outcomes of children adopted from institutional care.

Trauma and posttraumatic stress disorder modulate polygenic predictors of hippocampal and amygdala volume

The volume of subcortical structures represents a reliable, quantitative, and objective phenotype that captures genetic effects, environmental effects such as trauma, and disease effects such as posttraumatic stress disorder (PTSD). Trauma and PTSD represent potent exposures that may interact with genetic markers to influence brain structure and function. Genetic variants, associated with subcortical volumes in two large normative discovery samples, were used to compute polygenic scores (PGS) for the volume of seven subcortical structures. These were applied to a target sample enriched for childhood trauma and PTSD. Subcortical volume PGS from the discovery sample were strongly associated in our trauma/PTSD enriched sample (n = 7580) with respective subcortical volumes of the hippocampus (p = 1.10 × 10-20), thalamus (p = 7.46 × 10-10), caudate (p = 1.97 × 10-18), putamen (p = 1.7 × 10-12), and nucleus accumbens (p = 1.99 × 10-7). We found a significant association between the hippocampal volume PGS and hippocampal volume in control subjects from our sample, but was absent in individuals with PTSD (GxE; (beta = -0.10, p = 0.027)). This significant GxE (PGS × PTSD) relationship persisted (p < 1 × 10-19) in four out of five threshold peaks (0.024, 0.133, 0.487, 0.730, and 0.889) used to calculate hippocampal volume PGSs. We detected similar GxE (G × ChildTrauma) relationships in the amygdala for exposure to childhood trauma (rs4702973; p = 2.16 × 10-7) or PTSD (rs10861272; p = 1.78 × 10-6) in the CHST11 gene. The hippocampus and amygdala are pivotal brain structures in mediating PTSD symptomatology. Trauma exposure and PTSD modulate the effect of polygenic markers on hippocampal volume (GxE) and the amygdala volume PGS is associated with PTSD risk, which supports the role of amygdala volume as a risk factor for PTSD.

Early-life nicotine or cotinine exposure produces long-lasting sleep alterations and downregulation of hippocampal corticosteroid receptors in adult mice

Early-life exposure to environmental toxins like tobacco can permanently re-program body structure and function. Here, we investigated the long-term effects on mouse adult sleep phenotype exerted by early-life exposure to nicotine or to its principal metabolite, cotinine. Moreover, we investigated whether these effects occurred together with a reprogramming of the activity of the hippocampus, a key structure to coordinate the hormonal stress response. Adult male mice born from dams subjected to nicotine (NIC), cotinine (COT) or vehicle (CTRL) treatment in drinking water were implanted with electrodes for sleep recordings. NIC and COT mice spent significantly more time awake than CTRL mice at the transition between the rest (light) and the activity (dark) period. NIC and COT mice showed hippocampal glucocorticoid receptor (GR) downregulation compared to CTRL mice, and NIC mice also showed hippocampal mineralocorticoid receptor downregulation. Hippocampal GR expression significantly and inversely correlated with the amount of wakefulness at the light-to-dark transition, while no changes in DNA methylation were found. We demonstrated that early-life exposure to nicotine (and cotinine) concomitantly entails long-lasting reprogramming of hippocampal activity and sleep phenotype suggesting that the adult sleep phenotype may be modulated by events that occurred during that critical period of life.

Influence of early life stress on depression: from the perspective of neuroendocrine to the participation of gut microbiota

Depression is the most common mental disorder and has become a heavy burden in modern society. Clinical studies have identified early life stress as one of the high-risk factors for increased susceptibility to depression. Alteration of the hypothalamic-pituitary-adrenal (HPA) axis in response to stress is one of the key risk factors for depression susceptibility related to early life stress. Laboratory animal studies have demonstrated that maternal separation (MS) for extended periods elicits HPA axis changes. These changes persist into adulthood and resemble those present in depressed adult individuals, including hyperactivity of the HPA axis. In addition, there is growing evidence that inflammation plays an important role in depression susceptibility concerned with early life stress. Individuals that have experienced MS have higher levels of pro-inflammatory cytokines and are susceptible to depression. Recently, it has been found that the gut microbiota plays an important role in regulating behavior and is also associated with depression. The translocation of gut microbiota and the change of gut microbiota composition caused by early stress may be a reason. In this review, we discussed the mechanisms by which early life stress contributes to the development of depression in terms of these factors. These studies have facilitated a systematic understanding of the pathogenesis of depression related to early life stress and will provide new ideas for the prevention and treatment of depression.

Cellular Senescence in Adrenocortical Biology and Its Disorders

Cellular senescence is considered a physiological process along with aging and has recently been reported to be involved in the pathogenesis of many age-related disorders. Cellular senescence was first found in human fibroblasts and gradually explored in many other organs, including endocrine organs. The adrenal cortex is essential for the maintenance of blood volume, carbohydrate metabolism, reaction to stress and the development of sexual characteristics. Recently, the adrenal cortex was reported to harbor some obvious age-dependent features. For instance, the circulating levels of aldosterone and adrenal androgen gradually descend, whereas those of cortisol increase with aging. The detailed mechanisms have remained unknown, but cellular senescence was considered to play an essential role in age-related changes of the adrenal cortex. Recent studies have demonstrated that the senescent phenotype of zona glomerulosa (ZG) acts in association with reduced aldosterone production in both physiological and pathological aldosterone-producing cells, whereas senescent cortical-producing cells seemed not to have a suppressed cortisol-producing ability. In addition, accumulated lipofuscin formation, telomere shortening and cellular atrophy in zona reticularis cells during aging may account for the age-dependent decline in adrenal androgen levels. In adrenocortical disorders, including both aldosterone-producing adenoma (APA) and cortisol-producing adenoma (CPA), different cellular subtypes of tumor cells presented divergent senescent phenotypes, whereby compact cells in both APA and CPA harbored more senescent phenotypes than clear cells. Autonomous cortisol production from CPA reinforced a local cellular senescence that was more severe than that in APA. Adrenocortical carcinoma (ACC) was also reported to harbor oncogene-induced senescence, which compensatorily follows carcinogenesis and tumor progress. Adrenocortical steroids can induce not only a local senescence but also a periphery senescence in many other tissues. Therefore, herein, we systemically review the recent advances related to cellular senescence in adrenocortical biology and its associated disorders.

Mineralocorticoid pathway in retinal health and diseases

In the retina, the mineralocorticoid receptor (MR) is expressed in retinal and choroidal vessels and in cells from neural and glial origins. Like in the brain, the major ligand of the MR is cortisol and the MR/glucocorticoid receptor (GR) balance regulates the activation of the MR pathway. Experimental MR pathway activation using either pharmacological agents or transgenic manipulation favors retinal and choroidal pathology. In various models of retinal diseases, such as glaucomatous neuropathy, retinopathy of prematurity, ischemic retinopathies, diabetic retinopathy and choroidal neovascularization, MR antagonism exerts beneficial effects, demonstrating its potential in the treatment of major blinding retinal diseases. But specific formulations are required to optimize the bioavailability of MR antagonists in various compartments of the eye and molecular biomarkers of MR pathway activation remain to be identify in humans to select patients amenable to clinical trials.

Dysfunction of the hypothalamic‑pituitary‑adrenal axis in male rat offspring with prenatal food restriction: Fetal programming of hypothalamic hyperexcitability and poor hippocampal feedback

Prenatal food restriction (PFR) induces dysfunction of the hypothalamic-pituitary-adrenal (HPA) axis in the adult offspring. The aim of the present study was to identify the underlying mechanism of this process. Pregnant rats were placed on a restricted diet between gestational day 11 and 21. The offspring were fed with a high-fat diet and were subjected to unpredictable chronic stress (UCS) from postnatal week 17 to 20. A higher serum corticosterone (CORT) level was observed in the PFR fetuses. Although lower arginine vasopressin (AVP), hippocampal vesicular glutamate transporter 2 (vGLUT2) and glutamic acid decarboxylase 65 (GAD65) mRNA expression levels were detected in the hippocampi of PFR fetuses, the ratio of the mRNA expression levels of vGLUT2 and GAD65 was higher compared with that of the controls, which was accompanied by histopathological and ultrastructural abnormalities of both the hypothalamus and hippocampus. However, there were no marked changes in the hippocampal expression levels of glucocorticoids receptor (GR) and mineralocorticoids receptor (MR) or the ratio of MR/GR ratio. After the fetuses had matured, lower serum CORT and adrenocorticotropic hormone (ACTH) levels were observed in PFR rats without UCS when compared with the control. A higher rise rate of serum ACTH was also observed after UCS when compared with that in rats without UCS. Furthermore, the hypothalamic mRNA expression level of corticotrophin-releasing hormone (CRH) was lower in PFR rats without UCS, while expression levels of CRH, AVP, GAD65 and vGLUT2 were enhanced after UCS when compared with the control, accompanied by an increased vGLUT2/GAD65 expression ratio. MR mRNA expression was lower, and GR mRNA expression was higher in the hippocampus of the PFR rats without UCS when compared with the control. However, the mRNA expression levels of both MR and GR in the PFR rats were higher compared with those of the control after UCS, which was accompanied histopathological changes in the dentate gyrus, cornu ammonis (CA1) and CA3 areas. In summary, it was suggested that PFR induced fetal alterations of the HPA axis manifesting as hypothalamic hyperexcitability and poor hippocampal feedback, which persisted to adulthood and affected the behavior of the rat offspring.

Early Adversity and Development: Parsing Heterogeneity and Identifying Pathways of Risk and Resilience

Adversity early in life is common and is a major risk factor for the onset of psychopathology. Delineating the neurodevelopmental pathways by which early adversity affects mental health is critical for early risk identification and targeted treatment approaches. A rapidly growing cross-species literature has facilitated advances in identifying the mechanisms linking adversity with psychopathology, specific dimensions of adversity and timing-related factors that differentially relate to outcomes, and protective factors that buffer against the effects of adversity. Yet, vast complexity and heterogeneity in early environments and neurodevelopmental trajectories contribute to the challenges of understanding risk and resilience in the context of early adversity. In this overview, the author highlights progress in four major areas-mechanisms, heterogeneity, developmental timing, and protective factors; synthesizes key challenges; and provides recommendations for future research that can facilitate progress in the field. Translation across species and ongoing refinement of conceptual models have strong potential to inform prevention and intervention strategies that can reduce the immense burden of psychopathology associated with early adversity.

Combinatorial actions of glucocorticoid and mineralocorticoid stress hormone receptors are required for preventing neurodegeneration of the mouse hippocampus

Chronic stress contributes to numerous human pathologies including cognition impairments and psychiatric disorders. Glucocorticoids are primary stress hormones that activate two closely related nuclear receptors, the glucocorticoid (GR) and mineralocorticoid receptor (MR), that are both highly expressed in the hippocampus. To investigate potential combinatorial actions of hippocampal GR and MR, we developed mice with conditional knockout of both GR and MR in the hippocampus and compared them to their single knockout counterparts. Mice lacking MR alone or both GR and MR in the hippocampus exhibited altered expression of multiple CA2-specific neuronal markers and enhanced cue-dependent learning in a conditioned fear test. Provocatively, in contrast to the single knockouts, mice depleted of both GR and MR showed profound neurodegeneration of the hippocampus. Neuronal death was increased and neurogenesis was reduced in the dentate gyrus of the double knockout mice. Global gene expression assays of the knockout mice revealed a synergistic increase in the number of dysregulated genes in the hippocampus lacking both GR and MR. This large cohort of genes reliant on both GR and MR for expression was strongly associated with cell death and cell proliferation pathways. GR/MR complexes were detected in CA1 and dentate gyrus neurons suggesting receptor heterodimers contribute to the joint actions of GR and MR. These findings reveal an obligate role for MR signaling in regulating the molecular phenotype of CA2 neurons and demonstrate that combinatorial actions of GR and MR are essential for preserving dentate gyrus neurons and maintaining hippocampal health.

What was learned from studying the effects of early institutional deprivation

The effect of experiences in infancy on human development is a central question in developmental science. Children raised in orphanage-like institutions for their first year or so of life and then adopted into well-resourced and supportive families provide a lens on the long-term effects of early deprivation and the capacity of children to recover from this type of early adversity. While it is challenging to identify cause-and-effect relations in the study of previously institutionalized individuals, finding results that are consistent with animal experimental studies and the one randomized study of removal from institutional care support the conclusion that many of the outcomes for these children were induced by early institutional deprivation. This review examines the behavioral and neural evidence for altered executive function, declarative memory, affective disorders, reward processing, reactivity to threat, risk-taking and sensation-seeking. We then provide a brief overview of the neurobiological mechanisms that may transduce early institutional experiences into effects on brain and behavior. In addition, we discuss implications for policy and practice.

Trends in regional morphological changes in the brain after the resolution of hypercortisolism in Cushing's disease: a complex phenomenon, not mere partial reversibility

The adverse effects of hypercortisolism on the human brain have been highlighted in previous studies of Cushing's disease (CD). However, the relative alterations in regional hypercortisolism in the brain remain unclear. Thus, we investigated regional volumetric alterations in CD patients. We also analyzed the associations between these volumetric changes and clinical characteristics. The study participants comprised of active CD (n = 60), short-term-remitted CD (n = 28), and long-term-remitted CD (n = 32) patients as well as healthy control subjects (n = 66). Gray matter volumes (GMVs) were measured via voxel-based morphometry. The GMVs of substructures were defined using the automated anatomical labeling (AAL) atlas. Trends toward normalization in GMV were found in most brain substructures of CD patients. Different trends, including enlarged, irreversible, and unaffected, were observed in the other subregions, such as the amygdala, thalamus, and caudate. Morphological changes in GMVs after the resolution of hypercortisolism are a complex phenomenon; the characteristics of these changes significantly differ within the brain substructures.

Acute Cortisol Profile Associations With Cognitive Impairment After Severe Traumatic Brain Injury

BACKGROUND

Cognitive impairments commonly occur after traumatic brain injury (TBI) and affect daily functioning. Cortisol levels, which are elevated during acute hospitalization for most individuals after severe TBI, can influence cognition, but this association has not been studied previously in TBI.

OBJECTIVE

We hypothesized that serum and cerebral spinal fluid (CSF) cortisol trajectories over days 0-5 post-injury are associated with cognition 6-month post-injury.

METHODS

We examined 94 participants with severe TBI, collected acute serum and/or CSF samples over days 0-5 post-injury, and compared cortisol levels to those in 17 healthy controls. N = 88 participants had serum, and n = 84 had CSF samples available for cortisol measurement and had neuropsychological testing 6 months post-injury. Group based trajectory analysis (TRAJ) was used to generate temporal serum and CSF cortisol profiles which were examined for associations with neuropsychological performance. We used linear regression to examine relationships between cortisol TRAJ groups and both overall and domain-specific cognition.

RESULTS

TRAJ analysis identified a high group and a decliner group for serum and a high group and low group for CSF cortisol. Multivariable analysis showed serum cortisol TRAJ group was associated with overall cognitive composites scores (P = .024) and with executive function (P = .039) and verbal fluency (P = .029) domain scores. CSF cortisol TRAJ group was associated with overall cognitive composite scores (P = .021) and domain scores for executive function (P = .041), verbal fluency (P = .031), and attention (P = .034).

CONCLUSIONS

High acute cortisol trajectories are associated with poorer cognition 6 months post-TBI.

Sex-specific association of hair cortisol concentration with stress-related psychological factors in healthy young adults

BACKGROUND

Hair cortisol concentration (HCC) has received attention as a useful marker of stress, but evidence on associations between psychological factors and cortisol concentration is inconsistent. The purpose of this study was to investigate the sex differences in the relationship between cortisol concentration and psychological factors in healthy young adults.

METHODS

A total of 205 (103 females, 102 males) healthy young adults participated. HCC and various stress-related psychological measures were compared between sexes. Multiple linear regression analyses were performed to assess associations between HCC and stress-related psychological measures for all participants and for each sex.

RESULTS

The difference in HCC according to sex was not significant. The reported number of stressful life events in the past year, stress perception, depressive and anxiety-related symptoms, and emotion dysregulation were not different between sexes, either. The association between HCC and emotion dysregulation was significant in females but not males.

CONCLUSION

We observed a sex-specific association between HCC and psychological factors. Our findings may imply that HCC could be a useful biomarker of stress and stress-related emotion dysregulation in healthy young women.