Modulation of neurotransmitter systems by dehydroepiandrosterone and dehydroepiandrosterone sulfate: mechanism of action and relevance to psychiatric disorders

Androgen levels in autism spectrum disorders: a systematic review and meta-analysis

Background

Accumulating evidence suggests that the autism spectrum disorder (ASD) population exhibits altered hormone levels, including androgens. However, studies on the regulation of androgens, such as testosterone and dehydroepiandrosterone (DHEA), in relation to sex differences in individuals with ASD are limited and inconsistent. We conducted the systematic review with meta-analysis to quantitatively summarise the blood, urine, or saliva androgen data between individuals with ASD and controls.

Methods

A systematic search was conducted for eligible studies published before 16 January 2023 in six international and two Chinese databases. We computed summary statistics with a random-effects model. Publication bias was assessed using funnel plots and heterogeneity using I2 statistics. Subgroup analysis was performed by age, sex, sample source, and measurement method to explain the heterogeneity.

Results

17 case-control studies (individuals with ASD, 825; controls, 669) were assessed. Androgen levels were significantly higher in individuals with ASD than that in controls (SMD: 0.27, 95% CI: 0.06-0.48, P=0.01). Subgroup analysis showed significantly elevated levels of urinary total testosterone, urinary DHEA, and free testosterone in individuals with ASD. DHEA level was also significantly elevated in males with ASD.

Conclusion

Androgen levels, especially free testosterone, may be elevated in individuals with ASD and DHEA levels may be specifically elevated in males.

DHEA: a neglected biological signal that may affect fetal and child development

BACKGROUND

The stress-sensitive maternal hypothalamic-pituitary-adrenal (HPA) axis through the end-product cortisol, represents a primary pathway through which maternal experience shapes fetal development with long-term consequences for child neurodevelopment. However, there is another HPA axis end-product that has been widely ignored in the study of human pregnancy. The synthesis and release of dehydroepiandosterone (DHEA) is similar to cortisol, so it is a plausible, but neglected, biological signal that may influence fetal neurodevelopment. DHEA also may interact with cortisol to determine developmental outcomes. Surprisingly, there is virtually nothing known about human fetal exposure to prenatal maternal DHEA and offspring neurodevelopment. The current study examined, for the first time, the joint impact of fetal exposure to prenatal maternal DHEA and cortisol on infant emotional reactivity.

METHODS

Participants were 124 mother-infant dyads. DHEA and cortisol were measured from maternal hair at 15 weeks (early gestation) and 35 weeks (late gestation). Observational assessments of positive and negative emotional reactivity were obtained in the laboratory when the infants were 6 months old. Pearson correlations were used to examine the associations between prenatal maternal cortisol, prenatal maternal DHEA, and infant positive and negative emotional reactivity. Moderation analyses were conducted to investigate whether DHEA might modify the association between cortisol and emotional reactivity.

RESULTS

Higher levels of both early and late gestation maternal DHEA were linked to greater infant positive emotional reactivity. Elevated late gestation maternal cortisol was associated with greater negative emotional reactivity. Finally, the association between fetal cortisol exposure and infant emotional reactivity was only observed when DHEA was low.

CONCLUSIONS

These new observations indicate that DHEA is a potential maternal biological signal involved in prenatal programming. It appears to act both independently and jointly with cortisol to determine a child's emotional reactivity. Its role as a primary end-product of the HPA axis, coupled with the newly documented associations with prenatal development shown here, strongly calls for the inclusion of DHEA in future investigations of fetal programming.

Steroid Hormones as Modulators of Emotional Regulation in Male Urogenital Cancers

BACKGROUND

Tumors develop within an organism operating in a specific social and physical environment. Cortisol and dehydroepiandrosterone (DHEA), two of the most abundant steroid hormones in humans, are involved in both emotional regulation and the tumor progression. Several studies reported preclinical findings that DHEA can have preventive and therapeutic efficacy in treating major age-associated diseases, including cancer, although the mechanisms of action are not yet defined. The main aim of current study was to investigate the relationship between psychological and physiological emotional regulation and cancer development.

METHOD

This study assessed the quality of life of urogenital cancer male patients using several validated tools, including the Functional Assessment of Cancer Therapy-General and the Profile of Mood States. Saliva samples were collected to monitor peripheral activity of both cortisol and DHEA. It was hypothesized that patients with a better quality of life would have higher levels of the DHEA/cortisol ratios.

RESULTS

We found that the quality of life was positively related to DHEA, but not cortisol levels. Negative mood increases were related to lower levels of DHEA. Logistic regression of the predictors of metastases indicated three main independent factors involved: DHEA, age, and cortisol. In other words, the higher the DHEA levels in comparison to cortisol levels, controlling for age, the lower the probability of metastases.

CONCLUSION

Our results appear to support the hypothesis that emotional dysregulation mediated by DHEA/cortisol activity is a key factor in the probability of metastasis in urogenital cancers.

Effect of aerobic exercise on brain metabolite profiles in the mouse models of methamphetamine addiction: LC-MS-based metabolomics study

Methamphetamine (MA) abuse is recognized as a brain disorder, and physical activity has clear benefits for MA use disorders. The specific mechanisms by which physical activity alleviates MA use disorders are currently not fully understood. Based on this, the present study used untargeted metabolomics using liquid chromatography-mass spectrometry (LC-MS) to analyze the metabolic changes induced by MA in the brains of mice by exercise intervention. It was found that after 2 weeks of treadmill training, aerobic exercise modulated MA-induced brain metabolic disorders, in which 129 metabolites existed that were significantly differentiated in response to MA induction, and 32 metabolites were significantly affected by exercise. These differential metabolites were mainly enriched in glycerophospholipid metabolism, steroid hormone biosynthesis and degradation, and renin-angiotensin system pathways. To our knowledge, this study is the first to use LC-MS to investigate the effects of aerobic exercise on MA-induced brain metabolic profiling. The findings of this study provide new insights into exercise therapy using MA.

Dehydroepiandrosterone Sulfate (DHEAS) Is an Endogenous Kv7 Channel Modulator That Reduces Kv7/M-Current Suppression and Inflammatory Pain

Neuronal Kv7 voltage-gated potassium channels generate the M-current and regulate neuronal excitability. Here, we report that dehydroepiandrosterone sulfate (DHEAS) is an endogenous Kv7 channel modulator that attenuates Gq-coupled receptor-induced M-current suppression. DHEAS reduced muscarinic agonist-induced Kv7-current suppression of Kv7.1, Kv7.2, Kv7.4, or Kv7.5 homomeric currents and endogenous M-currents in rat sympathetic ganglion neurons. However, DHEAS per se did not alter the voltage dependence of these Kv7 homomeric channels or the m1 receptor-induced activation of phospholipase C or protein kinase C. DHEAS-treated Kv7.2 homomeric currents became resistant to depletion of phosphatidylinositol 4,5-bisphosphate (PIP2) induced by voltage-activated phosphatase, Ci-VSP or eVSP. Our computational models predicted a novel binding site for DHEAS in the cytoplasmic domain of Kv7 subunits. A single-point mutation of the predicted key histidine into cysteine in the rat Kv7.2 subunit, rKv7.2(H558C), resulted in a loss of effects of DHEAS on muscarinic Kv7 current suppression. Furthermore, in vivo administration of DHEAS in mice of both sexes reduced late phase pain responses in the formalin paw test. However, it did not have effects on early phase responses in the formalin paw test or responses in the hot plate test. Coadministration of a selective Kv7 inhibitor, XE991, and DHEAS eliminated analgesic effects of DHEAS in late phase responses in the formalin paw test. Collectively, these results suggest that DHEAS attenuates M-current suppression by stabilizing PIP2-Kv7 subunit interaction and can mitigate inflammatory pain.SIGNIFICANCE STATEMENT M-current suppression induced by stimulation of Gq-coupled receptors is a form of Kv7 current modulation that can reversibly increase neuronal excitability. This study demonstrates that DHEAS, an endogenous steroid hormone, is a novel Kv7 channel modulator that can attenuate M-current suppression without affecting basal Kv7 channel kinetics. Administration of DHEAS in vivo alleviated inflammatory pain in rodents. These results suggest that the degree of M-current suppression can be dynamically regulated by small molecules. Therefore, this novel form of Kv7 channel regulation holds promising potential as a therapeutic target for sensitized nervous activities, such as inflammatory pain.

Dehydroepiandrosterone (DHEA) increases undirected singing behavior and alters dopaminergic regulation of undirected song in non-breeding male European starlings (Sturnus vulgaris)

Introduction

It has been proposed that in species that defend territories across multiple life history stages, brain metabolism of adrenal dehydroepiandrosterone (DHEA) regulates aggressive behavior at times when gonadal androgen synthesis is low (i.e. the non-breeding season). To date, a role for DHEA in the regulation of other forms of social behavior that are expressed outside of the context of breeding remains unknown.

Methods

In this experiment, we used the European starling (Sturnus vulgaris) model system to investigate a role for DHEA in the neuroendocrine regulation of singing behavior by males in non-breeding condition. Starling song in a non-breeding context is spontaneous, not directed towards conspecifics, and functions to maintain cohesion of overwintering flocks.

Results

Using within-subjects design, we found that DHEA implants significantly increase undirected singing behavior by non-breeding condition male starlings. Given that DHEA is known to modulate multiple neurotransmitter systems including dopamine (DA) and DA regulates undirected song, we subsequently used immunohistochemistry for phosphorylated tyrosine hydroxylase (pTH, the active form of the rate-limiting enzyme in DA synthesis) to investigate the effect of DHEA on dopaminergic regulation of singing behavior in a non-breeding context. Pearson correlation analysis revealed a positive linear association between undirected singing behavior and pTH immunoreactivity in the ventral tegmental area and midbrain central gray of DHEA-implanted, but not control-implanted, males.

Discussion

Taken together, these data suggest that undirected singing behavior by non-breeding starlings is modulated by effects of DHEA on dopaminergic neurotransmission. More broadly, these data expand the social behavior functions of DHEA beyond territorial aggression to include undirected, affiliative social communication.

Stressing the need for validated measures of cortisol in HIV research: A scoping review

OBJECTIVES

People living with HIV experience numerous endocrine abnormalities and psychosocial stressors. However, interactions between HIV, cortisol levels, and health outcomes have not been well described among people living with HIV on effective therapy. Furthermore, methods for measuring cortisol are disparate across studies. We describe the literature reporting cortisol levels in people living with HIV, describe methods to measure cortisol, and explore how this relates to health outcomes.

METHODS

We searched the PubMed database for articles published in the past 20 years regarding HIV and cortisol with ≥50% of participants on antiretroviral therapies. Articles included observational, case-control, cross-sectional, and randomized controlled trials analyzing cortisol by any method. Studies were excluded if abnormal cortisol was due to medications or other infections. Variables were extracted from selected studies and their quality was assessed using the Newcastle-Ottawa Scale.

RESULTS

In total, 19 articles were selected and included, covering the prevalence of abnormal cortisol (n = 4), exercise (n = 4), metabolic syndrome and/or cardiovascular disease (n = 2), mental health and cognition (n = 9), and sex/gender (n = 6). Cortisol was measured in serum (n = 7), saliva (n = 8), urine (n = 2), and hair (n = 3) specimens. Comparisons between people with and without HIV were inconsistent, with some evidence that people with HIV have increased rates of hypocortisolism. Depression and cognitive decline may be associated with cortisol excess, whereas anxiety and metabolic disease may be related to low cortisol; more data are needed to confirm these relationships.

CONCLUSIONS

Data on cortisol levels in the era of antiretroviral therapy remain sparse. Future studies should include controls without HIV, appropriately timed sample collection, and consideration of sex/gender and psychosocial factors.

Acute stress influences strategy preference when dealing with high intensity emotions in men

Stress has been shown to initiate a shift from flexible to rigid, less demanding cognitive processes. Reappraisal and distraction are two emotion regulation strategies varying in their cognitive demands. Previous studies indicate that stress improves regulatory performances of high arousal stimuli. We thus investigated whether acute stress alters the preference for reappraisal or distraction when downregulating emotions of different intensities and further explored its influence on regulatory outcomes. Eighty males were either socially stressed (n=40) or exposed to a control condition (n=40) prior to an emotion regulation choice paradigm. Stress increased the probability to prefer distraction for downregulating high intensity emotions. Stressed (vs. control) participants reported to be generally more successful in regulating high intensity emotions, which was positively associated with cortisol but not alpha-amylase increases. Our findings provide initial evidence that stress fosters a preference for less demanding regulatory options, suggesting favorable strategy choices in response to acute stressors. DATA AVAILABILITY: The data that support the findings of this study are available at the Open Science Framework (OSF) under https://osf.io/b9ae3/.

Exploring the Impact of the Microbiome on Neuroactive Steroid Levels in Germ-Free Animals

Steroid hormones are essential biomolecules for human physiology as they modulate the endocrine system, nervous function and behaviour. Recent studies have shown that the gut microbiota is directly involved in the production and metabolism of steroid hormones in the periphery. However, the influence of the gut microbiota on levels of steroids acting and present in the brain (i.e., neuroactive steroids) is not fully understood. Therefore, using liquid chromatography–tandem mass spectrometry, we assessed the levels of several neuroactive steroids in various brain areas and the plasma of germ-free (GF) male mice and conventionally colonized controls. The data obtained indicate an increase in allopregnanolone levels associated with a decrease in those of 5α-androstane-3α, 17β-diol (3α-diol) in the plasma of GF mice. Moreover, an increase of dihydroprogesterone and isoallopregnanolone in the hippocampus, cerebellum, and cerebral cortex was also reported. Changes in dihydrotestosterone and 3α-diol levels were also observed in the hippocampus of GF mice. In addition, an increase in dehydroepiandrosterone was associated with a decrease in testosterone levels in the hypothalamus of GF mice. Our findings suggest that the absence of microbes affects the neuroactive steroids in the periphery and the brain, supporting the evidence of a microbiota-mediated modulation of neuroendocrine pathways involved in preserving host brain functioning.

The novel dehydroepiandrosterone (DHEA) derivative BNN27 counteracts cognitive deficits induced by the D1/D2 dopaminergic receptor agonist apomorphine in rats

RATIONALE

Schizophrenia is a devastating mental disease that affects nearly 1% of the population worldwide. It is well documented that the dopaminergic (DAergic) system is compromised in schizophrenia. It is of note that the mixed dopamine (DA) D₁/D₂ receptor agonist apomorphine induces schizophrenia-like symptoms in rodents, including disruption of memory abilities. Neuroactive steroids, comprising dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulphate (DHEAS), were shown to affect brain DAergic system and to be involved in schizophrenia. BNN27 is a novel DHEA derivative, which is devoid of steroidogenic activity. It has recently been reported that BNN27 counteracted schizophrenia-like behavioural deficits produced by glutamate hypofunction in rats.

OBJECTIVES

The aim of the present study was to investigate the ability of BNN27 to attenuate non-spatial, spatial recognition and discrete memory deficits induced by apomorphine in rats.

METHODS

To this end, the object recognition task (ORT), the object location task (OLT) and the step-through passive avoidance test (STPAT) were used.

RESULTS

BNN27 (3 and 6 mg/kg, i.p.) attenuated apomorphine (0.5 mg/kg, i.p.)-induced non-spatial, spatial recognition and discrete memory deficits. Interestingly, the effects of compounds on memory cannot be ascribed to changes in locomotor activity.

CONCLUSIONS

Our findings suggest that BNN27 is effective to DA dysfunction caused by apomorphine, attenuating cognitive impairments induced by this D1/D2 receptor agonist in rats. Additionally, our findings illustrate a functional interaction between BNN27 and the DAergic system that may be of relevance for schizophrenia-like behavioural symptoms.

Dehydroepiandrosterone increases tonic and phasic dopamine release in the striatum

Dehydroepiandrosterone (DHEA) modulates dopaminergic neurotransmission. It takes part in neurologic and psychiatric diseases involving monoamine neurotransmitters. Earlier results show that DHEA (120-min treatment) reduced striatal dopamine (DA) turnover in rats, suggesting a reduced DA release. Some investigations report that DHEA increases DA release but inhibits motor activity, which seems contradictory. This research examines the effect of DHEA on striatal DA release, its metabolism and motor activity. Male Wistar rats were implanted in the striatum with a cannula for in vivo microdialysis. DHEA was administered (120 mg/kg) and dialysates were collected for 280 min. A depolarizing stimulus was applied at 120 min. Samples were analyzed by HPLC-ED to determine the concentration of DA and its metabolites. The effect of DHEA on motor activity was also evaluated during 120 min. Extracellular DA concentration was greater in treated animals both before and after depolarization. In contrast, DHEA reduced the areas below the curves for DA metabolites and DA/metabolite ratios. DHEA also reduced motor activity, remarkably in the first 20 min after treatment. In summary, DHEA yielded a stimulatory effect on striatal DA release that was not reflected in neither DA metabolism nor motor activity. Thus, DHEA resembles the effect of typical antipsychotics, increasing DA release but reducing behavioral activation.

Dehydroepiandrosterone (DHEA) and its Sulphate (DHEAS) in Alzheimer's Disease

BACKGROUND

Neurosteroids Dehydroepiandrosterone (DHEA) and Dehydroepiandrosterone Sulphate (DHEAS) are involved in many important brain functions, including neuronal plasticity and survival, cognition and behavior, demonstrating preventive and therapeutic potential in different neuropsychiatric and neurodegenerative disorders, including Alzheimer's disease.

OBJECTIVE

The aim of the article was to provide a comprehensive overview of the literature on the involvement of DHEA and DHEAS in Alzheimer's disease.

METHODS

PubMed and MEDLINE databases were searched for relevant literature. The articles were selected considering their titles and abstracts. In the selected full texts, lists of references were searched manually for additional articles.

RESULTS

We performed a systematic review of the studies investigating the role of DHEA and DHEAS in various in vitro and animal models, as well as in patients with Alzheimer's disease, and provided a comprehensive discussion on their potential preventive and therapeutic applications.

CONCLUSION

Despite mixed results, the findings of various preclinical studies are generally supportive of the involvement of DHEA and DHEAS in the pathophysiology of Alzheimer's disease, showing some promise for potential benefits of these neurosteroids in the prevention and treatment. However, so far small clinical trials brought little evidence to support their therapy in AD. Therefore, large-scale human studies are needed to elucidate the specific effects of DHEA and DHEAS and their mechanisms of action, prior to their applications in clinical practice.

DHEAS and Human Development: An Evolutionary Perspective

Adrenarche, the post-natal rise of DHEA and DHEAS, is unique to humans and the African Apes. Recent findings have linked DHEA in humans to the development of the left dorsolateral prefrontal cortex (LDPFC) between the ages of 4-8 years and the right temporoparietal junction (rTPJ) from 7 to 12 years of age. Given the association of the LDLPFC with the 5-to-8 transition and the rTPJ with mentalizing during middle childhood DHEA may have played an important role in the evolution of the human brain. I argue that increasing protein in the diet over the course of human evolution not only increased levels of DHEAS, but linked meat consumption with brain development during the important 5- to-8 transition. Consumption of animal protein has been associated with IGF-1, implicated in the development of the adrenal zona reticularis (ZR), the site of DHEAS production. In humans and chimps, the zona reticularis emerges at 3-4 years, along with the onset of DHEA/S production. For chimps this coincides with weaning and peak synaptogenesis. Among humans, weaning is completed around 2 ½ years, while synaptogenesis peaks around 5 years. Thus, in chimpanzees, early cortical maturation is tied to the mother; in humans it may be associated with post-weaning provisioning by others. I call for further research on adrenarche among the African apes as a critical comparison to humans. I also suggest research in subsistence populations to establish the role of nutrition and energetics in the timing of adrenarche and the onset of middle childhood.

Verbal performance during stress in healthy older people: Influence of dehydroepiandrosterone (DHEA) and cortisol reactivity

The impact of stress on the dehydroepiandrosterone (DHEA) response in older population is understudied. This study investigated, in healthy older people, whether the DHEA and cortisol responses to the Trier Social Stress Test (TSST) was related to performance on this task. Both speech (rated by committee and self-rated) and arithmetic (number of mistakes) performance were assessed. Sixty-five participants (55-77 years old) were exposed to the TSST. Increases in negative affect, state anxiety, and cortisol levels could be observed, but there were no significant changes in positive affect or DHEA levels. Interestingly, a larger DHEA response was related to better verbal performance after controlling for the cortisol's reactivity. No relationships were found between hormonal responses and the arithmetic task performance. Our results suggest that, in healthy older people, an increase in DHEA levels in response to acute psychosocial stress may help them to cope with this stressor by increasing verbal performance.

Impact of adrenal hormones, reproductive aging, and major depression on memory circuitry decline in early midlife

Dehydroepiandrosterone-sulfate (DHEAS) is an adrenal androgen that is, in part, aromatized to estradiol. It continues to be produced after menopause and provides estrogenicity after depletion of ovarian hormones. Estradiol depletion contributes to memory circuitry changes over menopause, including changes in hippocampal (HIPP) and dorsolateral- and ventrolateral-prefrontal cortex (DLPFC; VLPFC) function. Further, major depressive disorder (MDD) patients have, in general, lower levels of estradiol and lower DHEAS than healthy controls, thus potentially a higher risk of adverse menopausal outcomes. We investigated whether higher DHEAS levels after menopause is associated with better memory circuitry function, especially in women with MDD. 212 adults (ages 45-55, 50% women) underwent clinical and fMRI testing. Participants performed a working memory (WM) N-back task and an episodic memory verbal encoding (VE) task during fMRI scanning. DHEAS levels were significantly associated with memory circuitry function, specifically in MDD postmenopausal women. On the WM task, lower DHEAS levels were associated with increased HIPP activity. On the VE task, lower DHEAS levels were associated with decreased activity in the HIPP and VLPFC. In contrast, there was no association between DHEAS levels and memory circuitry function in MDD pre/perimenopausal women, men, and non-MDD participants regardless of sex and reproductive status. In fact, MDD postmenopausal women with higher levels of DHEAS were similar to MDD pre/perimenopausal women and men. Thus, memory circuitry deficits associated with MDD and a lower ability of the adrenal gland to produce DHEAS after menopause may contribute to a lower ability to maintain intact memory function with age.

Dehydroepiandrosterone sulfate, free testosterone, and sex hormone-binding globulin on susceptibility to attention-deficit/hyperactivity disorder

The neuroendocrine system may affect the pathophysiology of gender differences in attention deficit/hyperactivity disorder (ADHD). This study examines whether the relationships among dehydroepiandrosterone sulfate (DHEA-S), free testosterone, or sex hormone-binding globulin (SHBG) and ADHD presentations exhibit gender differences. A total of 113 boys and 35 girls with ADHD (all drug naïve) and 46 and 26 healthy control boys and girls, respectively, were recruited. Blood samples were obtained to measure the serum levels of DHEA-S, free testosterone, and SHBG in each child. The Swanson, Nolan, and Pelham Scale for ADHD Version IV (SNAP-IV) was used to evaluate behavioral symptoms and the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) and the Conners' Continuous Performance Test (CPT) were utilized to assess neurocognitive functions. Patients with ADHD had lower DHEA-S levels than male and female healthy control subjects, and no significant differences were observed in free testosterone and SHBG levels between the patients and the controls. DHEA-S levels were negatively correlated with children's impulsivity performance in the CPT. SHBG levels were negatively correlated with ADHD behavior symptoms among boys. Free testosterone levels were not significantly correlated with either ADHD clinical symptoms or neuropsychological functions. We propose that DHEA-S serves as a potential biomarker of ADHD and is consistently involved in the pathogenesis of ADHD in both boys and girls. SHBG may be involved in behaviors associated with ADHD in boys. Additional studies with basic scientific measures are warranted to elucidate the relationship between androgen hormones and clinical presentations of ADHD.

Association of Brain Reward Learning Response With Harm Avoidance, Weight Gain, and Hypothalamic Effective Connectivity in Adolescent Anorexia Nervosa

IMPORTANCE

Anorexia nervosa (AN) is associated with adolescent onset, severe low body weight, and high mortality as well as high harm avoidance. The brain reward system could have an important role in the perplexing drive for thinness and food avoidance in AN.

OBJECTIVE

To test whether brain reward learning response to taste in adolescent AN is altered and associated with treatment response, striatal-hypothalamic connectivity, and elevated harm avoidance.

DESIGN, SETTING, AND PARTICIPANTS

In this cross-sectional multimodal brain imaging study, adolescents and young adults with AN were matched with healthy controls at a university brain imaging facility and eating disorder treatment program. During a sucrose taste classical conditioning paradigm, violations of learned associations between conditioned visual and unconditioned taste stimuli evoked the dopamine-related prediction error (PE). Dynamic effective connectivity during sweet taste receipt was studied to investigate hierarchical brain activation across the brain network that regulates eating. The study was conducted from July 2012 to May 2017, and data were analyzed from June 2017 to December 2017.

MAIN OUTCOMES AND MEASURES

Prediction error brain reward response across the insula, caudate, and orbitofrontal cortex; dynamic effective connectivity between hypothalamus and ventral striatum; and treatment weight gain, harm avoidance scores, and salivary cortisol levels and their correlations with PE brain response.

RESULTS

Of 56 female participants with AN included in the study, the mean (SD) age was 16.6 (2.5) years, and the mean (SD) body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) was 15.9 (0.9); of 52 matched female controls, the mean (SD) age was 16.0 (2.8) years, and the mean (SD) BMI was 20.9 (2.1). Prediction error response was elevated in participants with AN in the caudate head, nucleus accumbens, and insula (multivariate analysis of covariance: Wilks λ, 0.707; P = .02; partial η2 = 0.296), which correlated negatively with sucrose taste pleasantness. Bilateral AN orbitofrontal gyrus rectus PE response was positively correlated with harm avoidance (right ρ, 0.317; 95% CI, 0.091 to 0.539; P < .02; left ρ, 0.336; 95% CI, 0.112 to 0.550; P < .01) but negatively correlated with treatment BMI change (right ρ, -0.282; 95% CI, -0.534 to -0.014; P < .04; left ρ, -0.268; 95% CI, -0.509 to -0.018; P < .045). Participants with AN showed effective connectivity from ventral striatum to hypothalamus, and connectivity strength was positively correlated with insula and orbitofrontal PE response. Right frontal cortex PE response was associated with cortisol, which correlated with body dissatisfaction.

CONCLUSIONS AND RELEVANCE

These results further support elevated PE signal in AN and suggest a link between PE and elevated harm avoidance, brain connectivity, and weight gain in AN. Prediction error may have a central role in adolescent AN in driving anxiety and ventral striatal-hypothalamus circuit-controlled food avoidance.

PTSD and depressive symptoms are linked to DHEAS via personality

BACKGROUND

Research results on dehydroepiandrosterone sulfate ester (DHEAS) in post-traumatic stress disorder (PTSD) are inconsistent. We hypothesized that personality traits could be the confounders of DHEAS levels and disease symptoms, which could in part explain the discrepancy in findings.

METHOD

This study was a part of a broader project in which simultaneous psychological and biological investigations were carried out in hospital conditions. 380 male subjects were categorized in four groups: A) current PTSD (n = 132), B) lifetime PTSD (n = 66), C) trauma controls (n = 101), and D) healthy controls (n = 81), matched by age.

RESULTS

The level of DHEAS is significantly lower in the current PTSD group than in trauma controls. All groups significantly differ in personality traits Disintegration and Neuroticism (current PTSD group having the highest scores). DHEAS is related to both PTSD and depressive symptoms; however, Structural Equation Model (SEM) shows that the relations are indirect, realized via their confounder - personality trait Disintegration.

CONCLUSIONS

According to our project results, DHEAS is the second putative biomarker for trauma-related disorders that fails to fulfil this expectation. It appears to be more directly related to personality than to the disease symptoms (the first one being basal cortisol). Our data promote personality as a biologically based construct with seemingly important role in understanding the mental health status.

Developmental effects of androgens in the human brain

Neuroendocrine theories of brain development posit that androgens play a crucial role in sex-specific cortical growth, although little is known about the differential effects of testosterone and dehydroepiandrosterone (DHEA) on cortico-limbic development and cognition during adolescence. In this context, the National Institutes of Health Study of Normal Brain Development, a longitudinal study of typically developing children and adolescents aged 4-24 years (n=433), offers a unique opportunity to examine the developmental effects of androgens on cortico-limbic maturation and cognition. Using data from this sample, our group found that higher testosterone levels were associated with left-sided decreases in cortical thickness (CTh) in post-pubertal boys, particularly in the prefrontal cortex, compared to right-sided increases in CTh in somatosensory areas in pre-pubertal girls. Prefrontal-amygdala and prefrontal-hippocampal structural covariance (considered to reflect structural connectivity) also varied according to testosterone levels, with the testosterone-related brain phenotype predicting higher aggression levels and lower executive function, particularly in boys. By contrast, DHEA was associated with a pre-pubertal increase in CTh of several regions involved in cognitive control in both boys and girls. Covariance within several cortico-amygdalar structural networks also varied as a function of DHEA levels, with the DHEA-related brain phenotype predicting improvements in visual attention in both boys and girls. DHEA-related cortico-hippocampal structural covariance, on the other hand, predicted higher scores on a test of working memory. Interestingly, there were significant interactions between testosterone and DHEA, such that DHEA tended to mitigate the anti-proliferative effects of testosterone on brain structure. In sum, testosterone-related effects on the developing brain may lead to detrimental effects on cortical functions (ie, higher aggression and lower executive function), whereas DHEA-related effects may optimise cortical functions (ie, better attention and working memory), perhaps by decreasing the influence of amygdalar and hippocampal afferents on cortical functions.

Targeting the HPA axis in major depression: does it work?

In the search for antidepressant drugs with enhanced efficacy, targeting the hypothalamic–pituitary–adrenal (HPA) axis is a valid strategy. This commentary critically summarises the evidence for the efficacy of antidepressant drugs targeting the HPA axis, and concludes that the available clinical trials do not support claims that this class of drugs is superior to existing treatments.

Gender differences in susceptibility to schizophrenia: Potential implication of neurosteroids

Past research has indicated gender differences in the clinical characteristics and course of schizophrenia. In this study, we investigated whether gender differences in the manifestation of schizophrenia are correlated with neurosteroids, including dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA-S), and pregnenolone. We further explored the potential relationship between the aforementioned neurosteroids and psychopathology. We recruited 65 schizophrenic patients (36 males and 29 females) and 103 healthy control subjects (47 males and 56 females) and obtained blood samples from the subjects in the morning while in a fasting state to determine the serum levels of DHEA, DHEA-S, and pregnenolone. The psychopathology and mood symptoms of patients with schizophrenia were evaluated using the Positive and Negative Syndrome Scale (PANSS) and 17-item Hamilton Depression Rating Scale, respectively. Compared to the male control subjects, male patients with schizophrenia had significantly lower serum levels of DHEA and pregnenolone. In males with schizophrenia, the serum levels of DHEA and DHEA-S were associated with the age of onset and the duration of illness, while pregnenolone levels were associated with general symptoms of the PANSS. However, none of the neurosteroid levels were different between the female patients with schizophrenia and the female controls, and no significant correlation between neurosteroid levels and psychopathology evaluations was found among the schizophrenic females. Neurosteroids, including DHEA, DHEA-S, and pregnenolone, are involved in the pathophysiology of schizophrenia in male patients, but not in female ones. Therefore, our findings suggest that neurosteroids may be associated with gender differences in susceptibility to schizophrenia.

Cortisol and DHEA in development and psychopathology

Dehydroepiandrosterone (DHEA) and cortisol are the most abundant hormones of the human fetal and adult adrenals released as end products of a tightly coordinated endocrine response to stress. Together, they mediate short- and long-term stress responses and enable physiological and behavioral adjustments necessary for maintaining homeostasis. Detrimental effects of chronic or repeated elevations in cortisol on behavioral and emotional health are well documented. Evidence for actions of DHEA that offset or oppose those of cortisol has stimulated interest in examining their levels as a ratio, as an alternate index of adrenocortical activity and the net effects of cortisol. Such research necessitates a thorough understanding of the co-actions of these hormones on physiological functioning and in association with developmental outcomes. This review addresses the state of the science in understanding the role of DHEA, cortisol, and their ratio in typical development and developmental psychopathology. A rationale for studying DHEA and cortisol in concert is supported by physiological data on the coordinated synthesis and release of these hormones in the adrenal and by their opposing physiological actions. We then present evidence that researching cortisol and DHEA necessitates a developmental perspective. Age-related changes in DHEA and cortisol are described from the perinatal period through adolescence, along with observed associations of these hormones with developmental psychopathology. Along the way, we identify several major knowledge gaps in the role of DHEA in modulating cortisol in typical development and developmental psychopathology with implications for future research.

Higher serum DHEA concentrations before and after SSRI treatment are associated with remission of major depression

BACKGROUND

Dehydroepiandrosterone (DHEA) and its sulfated ester DHEA-sulfate (DHEA-S), (together DHEA[S]), are the most abundant adrenal steroids in humans and are found in blood and the brain, where they function as neurosteroids with direct receptor affinities. Preclinical studies suggest that DHEA(S) has antidepressant/neuroprotective properties, and exogenously administered DHEA has shown antidepressant efficacy in humans. Nonetheless, the role of endogenous DHEA(S) levels in major depressive disorder (MDD) and antidepressant outcomes remains unclear.

METHODS

Morning fasting serum DHEA(S) concentrations were determined in 36 healthy, unmedicated MDD adults with Hamilton Depression (HDRS) ratings ≥17, and 75 healthy controls. MDD participants then completed eight weeks of open-label SSRI treatment before DHEA(S) levels were re-sampled; those with post-treatment HDRS ratings ≤7 were classified as "Remitters." Pre- and post-treatment DHEA(S) levels of Remitters and Non-remitters were compared, controlling for age, sex, and BMI.

RESULTS

Pre-treatment HDRS ratings did not differ between Remitters and Non-remitters (p=0.179). Baseline DHEA levels of Remitters were significantly higher than both Non-remitters (p=0.008) and controls (p=0.004); baseline DHEA-S levels of Remitters were also higher than Non-remitters (p=0.040) but did not significantly differ from controls (p=0.096). Non-remitters did not significantly differ from controls. Post-treatment DHEA(S) levels remained higher in Remitters compared to Non-remitters (DHEA: p=0.013; DHEA-S: p=0.040).

CONCLUSIONS

These data suggest that higher circulating DHEA(S) levels (while unmedicated and after eight weeks of SSRI treatment) predict SSRI-associated remission in MDD. This raises the possibility that endogenous DHEA(S) abundance is a physiological adjunct to SSRI efficacy, as suggested by prior preclinical and clinical studies.

Sex Steroids and Major Psychoses: Which Role for DHEA-S and Progesterone

OBJECTIVE

Endocrine pathways seem to play a role in the etiology of major psychoses. The identification of biomarkers associated with psychotic symptoms in schizophrenia (SKZ) and mood disorders would allow the identification of high-risk subjects for delusions and hallucinations. The aim of this study was to evaluate dehydroepiandrosterone sulfate (DHEA-S) and progesterone plasma levels in drug-free patients with major psychoses and their relation with the diagnosis and history of psychotic symptoms.

METHODS

Eighty-nine consecutive drug-free male inpatients with SKZ or mood disorders were recruited, and DHEA-S and progesterone plasma levels were measured. The groups, divided according to pathological/normal-range hormone levels, were compared in terms of clinical variables using x03C7;2 tests with Bonferroni's corrections or multivariate analyses of variance. The same analyses were performed for groups divided according to the presence/absence of lifetime psychotic symptoms. Binary logistic regression analysis was performed using hormone levels as independent variables and history of lifetime psychotic symptoms as a dependent one.

RESULTS

A higher number of patients with abnormal DHEA-S levels was found to have a family history of major depressive disorder (p < 0.05). Higher DHEA-S levels (F = 8.31; p = 0.005) were found in patients with a history of psychotic symptoms. In addition, binary logistic regression confirmed that DHEA-S levels were associated with a higher probability of lifetime psychotic symptoms (p = 0.037).

CONCLUSIONS

Our results confirm previous data about the role of endocrine factors in the etiology of major psychoses. A high DHEA-S level might be a risk factor for psychotic symptoms. Studies with larger samples are needed to confirm these data.

Dehydroepiandrosterone Heightens Aggression and Increases Androgen Receptor and Aromatase mRNA Expression in the Brain of a Male Songbird

Dehydroepiandrosterone (DHEA) is a testosterone/oestrogen precursor and known modulator of vertebrate aggression. Male song sparrows (Melospiza melodia morphna) show high aggression during breeding and nonbreeding life-history stages when circulating DHEA levels are high, and low aggression during molt when DHEA levels are low. We previously showed that androgen receptor and aromatase mRNA expression are higher during breeding and/or nonbreeding in brain regions associated with reproductive and aggressive behaviour, although the potential role of DHEA in mediating these seasonal changes remained unclear. In the present study, nonbreeding male song sparrows were captured and held in the laboratory under short days (8 : 16 h light/dark cycle) and implanted with s.c. DHEA-filled or empty (control) implants for 14 days. DHEA implants increased aggression in a laboratory-based simulated territorial intrusion. Brains of DHEA-implanted birds showed higher aromatase mRNA expression in the preoptic area (POA) and higher androgen receptor mRNA expression in the periventricular nucleus of the medial striatum (pvMSt) and ventromedial nucleus of the hypothalamus. The DHEA-induced increases in aromatase expression in the POA and androgen receptor expression in the pvMSt are consistent with previously reported seasonal increases in these markers associated with naturally elevated DHEA levels. This suggests that DHEA facilitates seasonal increases in aggression in nonbreeding male song sparrows by up-regulating steroid signalling/synthesis machinery in a brain region-specific fashion.

Exposure to acute stress enhances decision-making competence: Evidence for the role of DHEA

Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol.

Effects of acute and chronic administration of neurosteroid dehydroepiandrosterone sulfate on neuronal excitability in mice

Background

Neurosteroid dehydroepiandrosterone sulfate (DHEAS) has been associated with important brain functions, including neuronal survival, memory, and behavior, showing therapeutic potential in various neuropsychiatric and cognitive disorders. However, the antagonistic effects of DHEAS on γ-amino-butyric acid_A receptors and its facilitatory action on glutamatergic neurotransmission might lead to enhanced brain excitability and seizures and thus limit DHEAS therapeutic applications. The aim of this study was to investigate possible age and sex differences in the neuronal excitability of the mice following acute and chronic DHEAS administration.

Methods

DHEAS was administered intraperitoneally in male and female adult and old mice either acutely or repeatedly once daily for 4 weeks in a 10 mg/kg dose. To investigate the potential proconvulsant properties of DHEAS, we studied the effects of acute and chronic DHEAS treatment on picrotoxin-, pentylentetrazole-, and N-methyl-D-aspartate-induced seizures in mice. The effects of acute and chronic DHEAS administration on the locomotor activity, motor coordination, and body weight of the mice were also studied. We also investigated the effects of DHEAS treatment on [³H]flunitrazepam binding to the mouse brain membranes.

Results

DHEAS did not modify the locomotor activity, motor coordination, body weight, and brain [³H]flunitrazepam binding of male and female mice. The results failed to demonstrate significant effects of single- and long-term DHEAS treatment on the convulsive susceptibility in both adult and aged mice of both sexes. However, small but significant changes regarding sex differences in the susceptibility to seizures were observed following DHEAS administration to mice.

Conclusion

Although our findings suggest that DHEAS treatment might be safe for various potential therapeutic applications in adult as well as in old age, they also support subtle interaction of DHEAS with male and female hormonal status, which may underline observed sex differences in the relationship between DHEAS and various health outcomes.

An ultrastructural analysis of the effects of ethanol self-administration on the hypothalamic paraventricular nucleus in rhesus macaques

A bidirectional relationship between stress and ethanol exists whereby stressful events are comorbid with problematic ethanol use and prolonged ethanol exposure results in adaptations of the physiological stress response. Endocrine response to stress is initiated in the hypothalamic paraventricular nucleus (PVN) with the synthesis and release of corticotropin-releasing hormone (CRH) and arginine-vasopressin (AVP). Alterations in CRH and AVP following long-term ethanol exposure in rodents is well demonstrated, however little is known about the response to ethanol in primates or the mechanisms of adaptation. We hypothesized that long-term ethanol self-administration in nonhuman primates would lead to ultrastructural changes in the PVN underlying adaptation to chronic ethanol. Double-label immunogold electron microscopy (EM) was used to measure presynaptic gamma-aminobutyric acid (GABA) and glutamate density within synaptic terminals contacting CRH- and AVP-immunoreactive dendrites. Additionally, pituitary-adrenal hormones (ACTH, cortisol, DHEA-s and aldosterone) under two conditions (low and mild stress) were compared before and after self-administration. All hormones were elevated in response to the mild stressor independent of ethanol consumption. The presynaptic glutamate density in recurrent (i.e., intra-hypothalamic) CRH terminals was highly related to ethanol intake, and may be a permissive factor in increased drinking due to stress. Conversely, glutamate density within recurrent AVP terminals showed a trend-level increase following ethanol, but was not related to average daily consumption. Glutamate density in non-recurrent AVP terminals was related to aldosterone under the low stress condition while GABAergic density in this terminal population was related to water consumption. The results reveal distinct populations of presynaptic terminals whose glutamatergic or GABAergic density were uniquely related to water and ethanol consumption and circulating hormones.

DHEA and cognitive function in the elderly

The adrenal prohormone dehydroepiandrosterone (DHEA) and its sulphate conjugate (DHEAS) steadily decrease with age by 10% per decade reaching a nadir after the age of 80. Both DHEA and DHEAS (DHEA/S) exert many biological activities in different tissues and organs. In particular, DHEA and DHEAS are produced de novo in the brain, hence their classification as neurosteroids. In humans, the brain-to-plasma ratios for DHEA and DHEAS are 4-6.5 and 8.5, respectively, indicating a specific neuroendocrine role for these hormones. DHEA/S stimulates neurite growth, neurogenesis and neuronal survival, apoptosis, catecholamine synthesis and secretion. Together with antioxidant, anti-inflammatory and anti-glucocorticoid properties, it has been hypothesized a neuroprotective effect for DHEA/S. We conducted an accurate research of the literature using PubMed. In the period of time between 1994 and 2013, we selected the observational human studies testing the relationship between DHEA/S and cognitive function in both sexes. The studies are presented according to the cross-sectional and longitudinal design and to the positive or neutral effects on different domains of cognitive function. We also analysed the Clinical Trials, available in the literature, having cognitive domains as the main or secondary outcome. Although the cross-sectional evidence of a positive association between DHEA/S and cognitive function, longitudinal studies and RCTs using DHEA oral treatment (50mg/day) in normal or demented adult-older subjects, have produced conflicting and inconsistent results. In summary, the current data do not provide clear evidence for the usefulness of DHEA treatment to improve cognitive function in adult-older subjects. This article is part of a Special Issue entitled 'Essential role of DHEA'.

Pregnenolone treatment reduces severity of negative symptoms in recent-onset schizophrenia: an 8-week, double-blind, randomized add-on two-center trial

AIMS

Management of recent-onset schizophrenia (SZ) and schizoaffective disorder (SA) is challenging owing to frequent insufficient response to antipsychotic agents. This study aimed to test the efficacy and safety of the neurosteroid pregnenolone in patients with recent-onset SZ/SA.

METHODS

Sixty out- and inpatients who met DSM-IV criteria for SZ/SA, with suboptimal response to antipsychotics were recruited for an 8-week, double-blind, randomized, placebo-controlled, two-center add-on trial, that was conducted between 2008 and 2011. Participants were randomized to receive either pregnenolone (50 mg/day) or placebo added on to antipsychotic medications. The primary outcome measures were the Positive and Negative Symptoms Scale and the Assessment of Negative Symptoms scores. Secondary outcomes included assessments of functioning, and side-effects.

RESULTS

Analysis was by linear mixed model. Fifty-two participants (86.7%) completed the trial. Compared to placebo, adjunctive pregnenolone significantly reduced Positive and Negative Symptoms Scale negative symptom scores with moderate effect sizes (d = 0.79). Significant improvement was observed in weeks 6 and 8 of pregnenolone therapy among patients who were not treated with concomitant mood stabilizers (arms × visit × mood stabilizers; P = 0.010). Likewise, pregnenolone significantly reduced Assessment of Negative Symptoms scores compared to placebo (d = 0.57), especially on blunted affect, avolition and anhedonia domain scores. Other symptoms, functioning, and side-effects were not significantly affected by adjunctive pregnenolone. Antipsychotic agents, benzodiazepines and sex did not associate with pregnenolone augmentation. Pregnenolone was well tolerated.

CONCLUSIONS

Thus, add-on pregnenolone reduces the severity of negative symptoms in recent-onset schizophrenia and schizoaffective disorder, especially among patients who are not treated with concomitant mood stabilizers. Further studies are warranted.

Prenatal antidepressant exposure: clinical and preclinical findings

Pharmacological treatment of any maternal illness during pregnancy warrants consideration of the consequences of the illness and/or medication for both the mother and unborn child. In the case of major depressive disorder, which affects up to 10-20% of pregnant women, the deleterious effects of untreated depression on the offspring can be profound and long lasting. Progress has been made in our understanding of the mechanism(s) of action of antidepressants, fetal exposure to these medications, and serotonin's role in development. New technologies and careful study designs have enabled the accurate sampling of maternal serum, breast milk, umbilical cord serum, and infant serum psychotropic medication concentrations to characterize the magnitude of placental transfer and exposure through human breast milk. Despite this progress, the extant clinical literature is largely composed of case series, population-based patient registry data that are reliant on nonobjective means and retrospective recall to determine both medication and maternal depression exposure, and limited inclusion of suitable control groups for maternal depression. Conclusions drawn from such studies often fail to incorporate embryology/neurotransmitter ontogeny, appropriate gestational windows, or a critical discussion of statistically versus clinically significant. Similarly, preclinical studies have predominantly relied on dosing models, leading to exposures that may not be clinically relevant. The elucidation of a defined teratological effect or mechanism, if any, has yet to be conclusively demonstrated. The extant literature indicates that, in many cases, the benefits of antidepressant use during pregnancy for a depressed pregnant woman may outweigh potential risks.

Interactive effects of dehydroepiandrosterone and testosterone on cortical thickness during early brain development

Humans and the great apes are the only species demonstrated to exhibit adrenarche, a key endocrine event associated with prepubertal increases in the adrenal production of androgens, most significantly dehydroepiandrosterone (DHEA) and to a certain degree testosterone. Adrenarche also coincides with the emergence of the prosocial and neurobehavioral skills of middle childhood and may therefore represent a human-specific stage of development. Both DHEA and testosterone have been reported in animal and in vitro studies to enhance neuronal survival and programmed cell death depending on the timing, dose, and hormonal context involved, and to potentially compete for the same signaling pathways. Yet no extant brain-hormone studies have examined the interaction between DHEA- and testosterone-related cortical maturation in humans. Here, we used linear mixed models to examine changes in cortical thickness associated with salivary DHEA and testosterone levels in a longitudinal sample of developmentally healthy children and adolescents 4-22 years old. DHEA levels were associated with increases in cortical thickness of the left dorsolateral prefrontal cortex, right temporoparietal junction, right premotor and right entorhinal cortex between the ages of 4-13 years, a period marked by the androgenic changes of adrenarche. There was also an interaction between DHEA and testosterone on cortical thickness of the right cingulate cortex and occipital pole that was most significant in prepubertal subjects. DHEA and testosterone appear to interact and modulate the complex process of cortical maturation during middle childhood, consistent with evidence at the molecular level of fast/nongenomic and slow/genomic or conversion-based mechanisms underlying androgen-related brain development.

The association of dehydroepiandrosterone and dehydroepiandrosterone sulfate with anxiety sensitivity and electronic diary negative affect among smokers with and without posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) is associated with increased smoking initiation, maintenance, and relapse. Dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) are neurosteroids that have been associated with mood measures as well as smoking status, and nicotine is associated with increased DHEA and DHEAS levels. Given the difficulties with mood experienced by smokers with PTSD, the purpose of the current study was to evaluate the association between negative affect and anxiety sensitivity with DHEA and DHEAS levels. Ninety-six smokers with and without PTSD provided blood samples for neurosteroid analyses and completed self-report measures of anxiety sensitivity and electronic diary ratings of negative affect. As expected, PTSD smokers reported higher levels of anxiety sensitivity (F(1,94) = 20.67, partial η2 = 0.18, P < 0.0001) and negative affect (F(1,91) = 7.98, partial η2 = 0.08, P = 0.006). After accounting for age and sex, DHEAS was significantly inversely associated with both anxiety sensitivity (F(3,92) = 6.97, partial η2 = 0.07, P = 0.01) and negative affect (F(3,87) = 10.52, partial η2 = 0.11, P = 0.002) across groups. Effect sizes indicated that these effects are moderate to high. No significant interactions of diagnosis and DHEA(S) levels with mood measures were detected. Given that nicotine is known to elevate DHEA(S) levels, these results suggest that DHEAS may serve as a biomarker of the association between mood and nicotine among smokers. Implications for the results include (1) the use of DHEAS measurement across time and across quit attempts and (2) the potential for careful use of DHEA supplementation to facilitate abstinence during smoking cessation.

Stress responsiveness of the hypothalamic-pituitary-adrenal axis: age-related features of the vasopressinergic regulation

The hypothalamic-pituitary-adrenal (HPA) axis plays a key role in adaptation to environmental stresses. Parvicellular neurons of the hypothalamic paraventricular nucleus secrete corticotrophin releasing hormone (CRH) and arginine vasopressin (AVP) into pituitary portal system; CRH and AVP stimulate adrenocorticotropic hormone (ACTH) release through specific G-protein-coupled membrane receptors on pituitary corticotrophs, CRHR1 for CRH and V1b for AVP; the adrenal gland cortex secretes glucocorticoids in response to ACTH. The glucocorticoids activate specific receptors in brain and peripheral tissues thereby triggering the necessary metabolic, immune, neuromodulatory, and behavioral changes to resist stress. While importance of CRH, as a key hypothalamic factor of HPA axis regulation in basal and stress conditions in most species, is generally recognized, role of AVP remains to be clarified. This review focuses on the role of AVP in the regulation of stress responsiveness of the HPA axis with emphasis on the effects of aging on vasopressinergic regulation of HPA axis stress responsiveness. Under most of the known stressors, AVP is necessary for acute ACTH secretion but in a context-specific manner. The current data on the AVP role in regulation of HPA responsiveness to chronic stress in adulthood are rather contradictory. The importance of the vasopressinergic regulation of the HPA stress responsiveness is greatest during fetal development, in neonatal period, and in the lactating adult. Aging associated with increased variability in several parameters of HPA function including basal state, responsiveness to stressors, and special testing. Reports on the possible role of the AVP/V1b receptor system in the increase of HPA axis hyperactivity with aging are contradictory and requires further research. Many contradictory results may be due to age and species differences in the HPA function of rodents and primates.

Adrenarche and middle childhood

Middle childhood, the period from 6 to 12 years of age, is defined socially by increasing autonomy and emotional regulation, somatically by the development of anatomical structures for subsistence, and endocrinologically by adrenarche, the adrenal production of dehydroepiandrosterone (DHEA). Here I suggest that DHEA plays a key role in the coordinated development of the brain and body beginning with middle childhood, via energetic allocation. I argue that with adrenarche, increasing levels of circulating DHEA act to down-regulate the release of glucose into circulation and hence limit the supply of glucose which is needed by the brain for synaptogenesis. Furthermore, I suggest the antioxidant properties of DHEA may be important in maintaining synaptic plasticity throughout middle childhood within slow-developing areas of the cortex, including the insula, thamalus, and anterior cingulate cortex. In addition, DHEA may play a role in the development of body odor as a reliable social signal of behavioral changes associated with middle childhood.

Reduced brain levels of DHEAS in hepatic coma patients: significance for increased GABAergic tone in hepatic encephalopathy

Increased neurosteroids with allosteric modulatory activity on GABA(A) receptors such as 3α-5α tertrahydroprogesterone; allopregnanolone (ALLO), are candidates to explain the phenomenon of "increased GABAergic tone" in hepatic encephalopathy (HE). However, it is not known how changes of other GABA(A) receptor modulators such as dehydroepiandrosterone sulfate (DHEAS) contribute to altered GABAergic tone in HE. Concentrations of DHEAS were measured by radioimmunoassay in frontal cortex samples obtained at autopsy from 11 cirrhotic patients who died in hepatic coma and from an equal number of controls matched for age, gender, and autopsy delay intervals free from hepatic or neurological diseases. To assess whether reduced brain DHEAS contributes to increased GABAergic tone, in vitro patch clamp recordings in rat prefrontal cortex neurons were performed. A significant reduction of DHEAS (5.81±0.88 ng/g tissue) compared to control values (9.70±0.79 ng/g, p<0.01) was found. Brain levels of DHEAS in patients with liver disease who died without HE (11.43±1.74 ng/g tissue), and in a patient who died in uremic coma (12.56 ng/g tissue) were within the control range. Increasing ALLO enhances GABAergic tonic currents concentration-dependently, but increasing DHEAS reduces these currents. High concentrations of DHEAS (50 μM) reduce GABAergic tonic currents in the presence of ALLO, whereas reduced concentrations of DHEAS (1 μM) further stimulate these currents. These findings demonstrate that decreased concentrations of DHEAS together with increased brain concentrations of ALLO increase GABAergic tonic currents synergistically; suggesting that reduced brain DHEAS could further increase GABAergic tone in human HE.

Dehydroepiandrosterone (DHEA) inhibits voltage-gated T-type calcium channels

BACKGROUND AND PURPOSE

Dehydroepiandrosterone (DHEA) and its sulfated form, DHEAS, are the most abundant steroid hormones in the mammalian blood flow. DHEA may have beneficial effects in various pathophysiological conditions such as cardiovascular diseases or deterioration of the sense of well-being. However to date, the cellular mechanism underlying DHEA action remains elusive and may involve ion channel modulation. In this study, we have characterized the effect of DHEA on T-type voltage-activated calcium channels (T-channels), which are involved in several cardiovascular and neuronal diseases.

KEY RESULTS

Using the whole-cell patch-clamp technique, we demonstrate that DHEA inhibits the three recombinant T-channels (Ca(V)3.1, Ca(V)3.2 and Ca(V)3.3) expressed in NG108-15 cell line, as well as native T-channels in pulmonary artery smooth muscle cells. This effect of DHEA is both concentration (IC(50) between 2 and 7μM) and voltage-dependent and results in a significant shift of the steady-state inactivation curves toward hyperpolarized potentials. Consequently, DHEA reduces window T-current and inhibits membrane potential oscillations induced by Ca(V)3 channels. DHEA inhibition is not dependent on the activation of nuclear androgen or estrogen receptors and implicates a PTX-sensitive Gi protein pathway. Functionally, DHEA and the T-type inhibitor NNC 55-0396 inhibited KCl-induced contraction of pulmonary artery rings and their effect was not cumulative.

CONCLUSIONS

Altogether, the present data demonstrate that DHEA inhibits T-channels by a Gi protein dependent pathway. DHEA-induced alteration in T-channel activity could thus account for its therapeutic action and/or physiological effects.

Aging of the hypothalamic-pituitary-adrenal axis in nonhuman primates with depression-like and aggressive behavior

We have investigated aging of the hypothalamic-pituitary-adrenal (HPA) axis in female rhesus monkeys that differ in adaptive behavior. Plasma cortisol (F) and dehydroepiandrosterone sulfate (DHEA-S) concentrations under basal conditions and under acute psycho-emotional stress were evaluated in blood plasma of young (6-8 years) and old (20-27 years) female rhesus monkeys with various types of adaptive behavior (aggressive, depression-like, and average). We have found that the age-related changes in the HPA axis of monkeys with depression-like behavior were accompanied by the maximal absolute and relative hypercortisolemia under both basal conditions and stress. Moreover, young aggressive monkeys, in comparison with young monkeys of other behavior groups, demonstrated the highest plasma levels of DHEA-S and the lowest molar ratios between F and DHEA-S. Thus, age-related dysfunctions of the HPA axis are associated with adaptive behavior of animals.

Organic anion transporter 3 mediates the efflux transport of an amphipathic organic anion, dehydroepiandrosterone sulfate, across the blood-brain barrier in mice

The present study investigated the efflux transport systems of organic anions across the blood-brain barrier (BBB) using dehydroepiandrosterone sulfate (DHEAS) as a probe. The elimination of DHEAS from the brain after microinjection into the cerebral cortex was characterized in wild-type mice and mice with deficiency of well characterized organic anion transporters, organic anion-transporting polypeptide 1a4 (Oatp1a4)/Slco1a4 and organic anion transporter 3 (Oat3)/Slc22a8, at the BBB. The saturable efflux of DHEAS from the brain was completely inhibited by probenecid, benzylpenicillin, and estrone-3-sulfate and moderately inhibited by taurocholate and p-aminohippurate (50-57%). Uptake of DHEAS and estrone-3-sulfate was greater in murine Oat3 cRNA-injected oocytes than that in water-injected oocytes. Efflux of these compounds from the brain was significantly delayed in Oat3(-/-) mice compared with that in wild-type mice, indicating that indeed Oat3 is functionally important in vivo. Furthermore, probenecid and taurocholate inhibited DHEAS efflux completely in Oat3(-/-) mice. Contrary to the past report in rats that suggested involvement of Oatp1a4, specific uptake of DHEAS and estrone-3-sulfate by murine Oatp1a4 was not detected in vitro, and efflux of both compounds from the brain was not altered in Oatp1a4(-/-) mice. There was no significant difference in the uptake of DHEAS by brain slices prepared from wild-type, Oatp1a4(-/-), and Oat3(-/-) mice. Taken together, these results suggest that Oat3 plays a significant role in the efflux of steroid conjugates across the BBB in mice and that the BBB also expresses other unknown organic anion transporters for the efflux of DHEAS. Transport mechanisms of organic anions at the BBB are far more diverse than they were assumed to be.

Evolutionary functions of early social modulation of hypothalamic-pituitary-adrenal axis development in humans

The hypothalamic-pituitary-adrenal axis (HPAA) is highly responsive to social challenges. Because stress hormones can have negative developmental and health consequences, this presents an evolutionary paradox: Why would natural selection have favored mechanisms that elevate stress hormone levels in response to psychosocial stimuli? Here we review the hypothesis that large brains, an extended childhood and intensive family care in humans are adaptations resulting from selective forces exerted by the increasingly complex and dynamic social and cultural environment that co-evolved with these traits. Variations in the modulation of stress responses mediated by specific HPAA characteristics (e.g., baseline cortisol levels, and changes in cortisol levels in response to challenges) are viewed as phenotypically plastic, ontogenetic responses to specific environmental signals. From this perspective, we discuss relations between physiological stress responses and life history trajectories, particularly the development of social competencies. We present brief summaries of data on hormones, indicators of morbidity and social environments from our long-term, naturalistic studies in both Guatemala and Dominica. Results indicate that difficult family environments and traumatic social events are associated with temporal elevations of cortisol, suppressed reproductive functioning and elevated morbidity. The long-term effects of traumatic early experiences on cortisol profiles are complex and indicate domain-specific effects, with normal recovery from physical stressors, but some heightened response to negative-affect social challenges. We consider these results to be consistent with the hypothesis that developmental programming of the HPAA and other neuroendocrine systems associated with stress responses may facilitate cognitive targeting of salient social challenges in specific environments.