Dehydroepiandrosterone antagonizes the neurotoxic effects of corticosterone and translocation of stress-activated protein kinase 3 in hippocampal primary cultures

Are there any differences between stress hormone levels in non-stress conditions and in potentional stress overload (heart catheterisation) in sows?

In order to study a possible effect of mini-invasive heart intervention on a response of hypothalamo-pituitary-adrenal stress axis, we analyzed four stress markers (cortisol, cortisone, DHEA and DHEAS) in 25 sows using minimally invasive heart catheterisation as the stress factor. The marker levels were assessed in four periods of the experiment, (1) the baseline level on the day before intervention, (2) after the introduction of anesthesia, (3) after conducting tissue stimulation or ablation, and (4) after the end of the catheterisation. For statistical analyses we used the non-parametric Friedman test for four dependent samples (including all four stages of the operation) or three dependent samples (influence of operation only, baseline level was excluded). Statistically significant differences in both Friedman tests were found for cortisol and for cortisone. Significant differences for DHEA as well as for DHEAS were found for all tested stages but not for the effect of operation itself. We have concluded that cortisol levels are blunted by the influence of anesthesia after its administration, and therefore decrease back to the baseline at the end of the operation. The other markers (cortisone, DHEA and DHEAS) acted as balanced systems against the injurious stress effect.

The role of acute cortisol and DHEAS in predicting acute and chronic PTSD symptoms

BACKGROUND

Decreased activation of the hypothalamus-pituitary-adrenal (HPA) axis in response to stress is suspected to be a vulnerability factor for posttraumatic stress disorder (PTSD). Previous studies showed inconsistent findings regarding the role of cortisol in predicting PTSD. In addition, no prospective studies have examined the role of dehydroepiandrosterone (DHEA), or its sulfate form DHEAS, and the cortisol-to-DHEA(S) ratio in predicting PTSD. In this study, we tested whether acute plasma cortisol, DHEAS and the cortisol-to-DHEAS ratio predicted PTSD symptoms at 6 weeks and 6 months post-trauma.

METHODS

Blood samples of 397 adult level-1 trauma center patients, taken at the trauma resuscitation room within hours after the injury, were analyzed for cortisol and DHEAS levels. PTSD symptoms were assessed at 6 weeks and 6 months post-trauma with the Clinician Administered PTSD Scale.

RESULTS

Multivariate linear regression analyses showed that lower cortisol predicted PTSD symptoms at both 6 weeks and 6 months, controlling for age, gender, time of blood sampling, injury, trauma history, and admission to intensive care. Higher DHEAS and a smaller cortisol-to-DHEAS ratio predicted PTSD symptoms at 6 weeks, but not after controlling for the same variables, and not at 6 months.

CONCLUSIONS

Our study provides important new evidence on the crucial role of the HPA-axis in response to trauma by showing that acute cortisol and DHEAS levels predict PTSD symptoms in survivors of recent trauma.

Adrenal steroidogenesis following prenatal dexamethasone exposure in the spiny mouse

Antenatal stress disturbs the development of the fetal hypothalamic-pituitary-adrenal axis and adrenal steroidogenesis. We investigated the effect of brief maternal exposure to high glucocorticoids (dexamethasone (DEX)) at mid- and late-pregnancy on adrenal structure and production of steroids in spiny mouse. Pregnant spiny mice were treated for 60 h with 125 μg/kg DEX or saline s.c. by osmotic minipump at day 20 (0.5) or 30 (0.75) of gestation. Immunohistochemical expression of steroidogenic acute regulatory-protein (StAR), 3β-hydroxysteroid dehydrogenase (3βHSD), 17-hydroxylase,17-20lyase (P450C17), and cytochromeb5 (CYTB5) was determined in adrenals on postnatal (P) day 170±20. DHEA, testosterone, and cortisol were measured by RIA. Maternal DEX at 20 days significantly reduced the expression of STAR, P450C17 (CYP17A1), and CYTB5 in the adrenal zona reticularis (ZR) of adult offspring, with greater change in male vs female offspring (P<0.05). Plasma DHEA was decreased in male offspring from DEX-treated (6.84±1.24 ng/ml) vs saline-treated (13±0.06 ng/ml; P=0.01) dams, and the DHEA:cortisol ratio was lower in males (P<0.05). Testosterone levels increased in male offspring from DEX (266.03±50.75 pg/ml) vs saline (83.47±32.3 pg/ml, P<0.05)-treated dams. DEX treatment at 0.75 gestation had no significant effect on any parameters measured. This study shows that brief exposure to excess glucocorticoid has long-term impacts on the ZR and adrenal steroidogenesis, affecting the secretion of DHEA and testosterone in male offspring, an effect produced at 0.5 but not at 0.75 gestation. DHEA is important for brain development, and its suppression in adult life might contribute to the neurobehavioral pathologies that can arise after illness and stress during pregnancy.

Stress responsive biochemical anabolic/catabolic ratio and telomere length in older adults

It has been hypothesized that chronic psychological stress is associated with shorter telomere length; however, the mechanisms that link stress and telomere length are not well understood. To examine the interplay between biochemical factors related to stress arousal and cellular aging, we investigate the association between anabolic/catabolic (A/C) imbalance and leukocyte telomere length (LTL) in the Social Environment and Biomarkers of Aging Study (SEBAS), conducted in Taiwan (N = 925). SEBAS participants aged 54 and older (mean age 68.3) with values for two anabolic hormones (serum dehydroepiandrosterone sulfate [DHEAS] and insulin growth factor [IGF]-1), four catabolic hormones (cortisol, epinephrine, norepinephrine, and interleukin-6 [IL-6]), and LTL were examined. We found that high IL-6 was associated with short LTL (≤ 0.88 T/S ratio; odds ratio [OR] 1.41, 95% confidence interval [CI] = 1.04-1.92). Neither DHEAS/cortisol nor IGF-1/cortisol ratio was associated with telomere length; however, a high A/C imbalance summary score was associated with greater odds of having a short LTL relative to long LTL (OR 1.19, 95% CI = 1.05-1.35). These results indicate that our A/C imbalance score, defined by several anabolic and catabolic biochemical factors, may be one mechanism through which psychological stress is associated with short LTL and possibly cellular senescence.

Dehydroepiandrosterone stimulates nerve growth factor and brain derived neurotrophic factor in cortical neurons

Due to the increasing cases of neurodegenerative diseases in recent years, the eventual goal of nerve repair is very important. One approach for achieving a neuronal cell induction is by regenerative pharmacology. Nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) are neurotrophins that play roles in neuronal development, differentiation, and protection. On the other hand, dehydroepiandrosterone (DHEA) is a neurosteroid which has multiple actions in the nervous system. DHEA could be an important agent in regenerative pharmacology for neuronal differentiation during tissue regeneration. In this study, we investigated the possible role of DHEA to modulate NGF and BDNF production. The in vivo level of neurotrophins expression was demonstrated by ELISA in rat harvested brain cortex. Also neurotrophins expression after DHEA treatment was revealed by the increased neurite extension, immunostaining, and BrdU labeling in rats. Anti-NGF and anti-BDNF antibodies were used as suppressive agents on neurogenesis. The results showed that NGF and BDNF are overproduced after DHEA treatment but there is not any overexpression for NT-3 and NT-4. Also DHEA increased neurite extension and neural cell proliferation significantly. Overall, DHEA might induce NGF and BDNF neurotrophins overproduction in cortical neurons which promotes neural cell protection, survival, and proliferation.

Psychometric and neurobiological assessment of resilience in a non-clinical sample of adults

BACKGROUND

Resilient individuals are capable of adjusting and coping successfully in the face of adversity. Efforts to assess resilience and its biomarkers have focused on individuals with a history of trauma and related disorders.

OBJECTIVE

To psychologically assess resilience in a non-clinical community population through questionnaires, and analyse the associations between the psychological parameters and salivary cortisol and dehydroepiandrosterone sulphate (DHEA-S) as putative biomarkers of resilience.

METHOD

An opportunistic sample (n=196) completed a cross-sectional survey assessing resilience, self-reported depressive symptoms and anxiety, and possible correlates. A sub-sample (n=32) selected in order to maximise variation of mental health, provided saliva samples for enzyme-linked immunoassay (ELISA) detection of cortisol and DHEA-S.

RESULTS

Resilience correlated negatively with depressive symptoms, trait anxiety and early life stress, and positively with self-efficacy, optimism, social support and wellbeing (all r>0.40; all p-values ≤0.001 except for early life stress: r=-0.20; p≤0.05). Resilience and DHEA-S concentrations correlated significantly (r=0.35; p≤0.05); this relationship remained stable after adjustment for demographics. Gender differences were observed for DHEA-S and cortisol (p≤0.05).

CONCLUSION

Resilience is associated with positive aspects of psychological health and salivary DHEA-S, suggesting the latter can be treated as a biomarker of resilience in a non-clinical sample of adults.

Ontogeny of the adrenal gland in the spiny mouse, with particular reference to production of the steroids cortisol and dehydroepiandrosterone

Synthesis of the androgen dehydroepiandrosterone (DHEA) by the fetal adrenal gland is important for placental estrogen production and may also be important for modulating the effects of glucocorticoids on the developing brain. The presence of cortisol in spiny mouse (Acomys cahirinus) blood led us to determine whether the adrenal gland of this precocial rodent also synthesized DHEA. Cytochrome P450 enzyme 17α-hydroxylase/17,20-lyase (P450c17), cytochrome-b5 (Cytb5), and 3β-hydroxysteroid dehydrogenase (3βHSD) were detected in the adrenal gland from 30 days gestation (term = 39 days), and DHEA, cortisol, and aldosterone were detected in fetal plasma from this time. Plasma DHEA concentrations increased 4-fold, whereas cortisol concentrations decreased from day 30 of gestation until the day of birth. Explant culture of fetal adrenal tissue showed that DHEA was produced from exogenous pregnenolone, and thus, the DHEA in the fetal circulation is likely to be of fetal origin. Clear zonation of the fetal adrenal cortex was evident by 38 days gestation when expression of Cytb5 was present throughout the cortex, and coexpression of P450c17 and Cytb5 occurred in the zona reticularis and fasciculata. 3βHSD was expressed in the cortex from at least 30 days gestation and decreased as term approached, consistent with the fall of cortisol in late gestation in this species. These results show that the spiny mouse adrenal gland, like that of the human fetus, can synthesize and secrete DHEA from at least 30 days (relative gestation length, 30 days of a 39-day gestation, 0.76) of gestation, and DHEA may have important roles in placental biosynthesis of estrogens and in modulating the actions of glucocorticoids in the developing brain in this species.

The hormonal pathway to cognitive impairment in older men

In older men there is a multiple hormonal dysregulation with a relative prevalence of catabolic hormones such as thyroid hormones and cortisol and a decline in anabolic hormones such as dehydroepiandrosterone sulphate, testosterone and insulin like growth factor 1 levels. Many studies suggest that this catabolic milieu is an important predictor of frailty and mortality in older persons. There is a close relationship between frailty and cognitive impairment with studies suggesting that development of frailty is consequence of cognitive impairment and others pointing out that physical frailty is a determinant of cognitive decline. Decline in cognitive function, typically memory, is a major symptom of dementia. The "preclinical phase" of cognitive impairment occurs many years before the onset of dementia. The identification of relevant modifiable factors, including the hormonal dysregulation, may lead to therapeutic strategies for preventing the cognitive dysfunction. There are several mechanisms by which anabolic hormones play a role in neuroprotection and neuromodulation. These hormones facilitate recovery after brain injury and attenuate the neuronal loss. In contrast, elevated thyroid hormones may increase oxidative stress and apoptosis, leading to neuronal damage or death. In this mini review we will address the relationship between low levels of anabolic hormones, changes in thyroid hormones and cognitive function in older men. Then, giving the contradictory data of the literature and the multi-factorial origin of dementia, we will introduce the hypothesis of multiple hormonal derangement as a better determinant of cognitive decline in older men.

Effects of dehydroepiandrosterone supplementation during stressful military training: a randomized, controlled, double-blind field study

Dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) are anabolic prehormones involved in the synthesis of testosterone. Both have been shown to exert neuroprotective effects during stress. In this randomized, controlled, double-blind field study, we examined the effects of a 12-day DHEA regimen on stress indices in military men undergoing survival training. Forty-eight men were randomized to either a DHEA treatment group or placebo control group. The treatment group received 50 mg of oral DHEA supplementation daily for 5 days during classroom training followed by 7 days of 75 mg during stressful field operations. Control subjects received identical placebo pills. Salivary assays (DHEA[S], testosterone, and cortisol) were conducted at four time points: distal pre-stress (T1), proximal pre-stress (T2), mock-captivity stress (T3), and 24 h recovery (T4). Subjective distress was also assessed at T1, T3, and T4. As expected, DHEA treatment resulted in higher salivary concentrations of DHEA and DHEAS during daily living, mock-captivity stress, and recovery. Similar patterns were observed for salivary markers of anabolic balance: DHEA/cortisol, DHEAS/cortisol, and testosterone/cortisol concentration ratios. Despite notable time effects, no group differences emerged for subjective distress. A brief, low dose DHEA regimen yielded large increases in salivary DHEA(S) concentrations and enhanced anabolic balance throughout sustained military stress. These physiological changes did not extrapolate to subjective distress.

Regulation of neurosteroid biosynthesis by neurotransmitters and neuropeptides

The enzymatic pathways leading to the synthesis of bioactive steroids in the brain are now almost completely elucidated in various groups of vertebrates and, during the last decade, the neuronal mechanisms involved in the regulation of neurosteroid production have received increasing attention. This report reviews the current knowledge concerning the effects of neurotransmitters, peptide hormones, and neuropeptides on the biosynthesis of neurosteroids. Anatomical studies have been carried out to visualize the neurotransmitter- or neuropeptide-containing fibers contacting steroid-synthesizing neurons as well as the neurotransmitter, peptide hormones, or neuropeptide receptors expressed in these neurons. Biochemical experiments have been conducted to investigate the effects of neurotransmitters, peptide hormones, or neuropeptides on neurosteroid biosynthesis, and to characterize the type of receptors involved. Thus, it has been found that glutamate, acting through kainate and/or AMPA receptors, rapidly inactivates P450arom, and that melatonin produced by the pineal gland and eye inhibits the biosynthesis of 7α-hydroxypregnenolone (7α-OH-Δ(5)P), while prolactin produced by the adenohypophysis enhances the formation of 7α-OH-Δ(5)P. It has also been demonstrated that the biosynthesis of neurosteroids is inhibited by GABA, acting through GABA(A) receptors, and neuropeptide Y, acting through Y1 receptors. In contrast, it has been shown that the octadecaneuropetide ODN, acting through central-type benzodiazepine receptors, the triakontatetraneuropeptide TTN, acting though peripheral-type benzodiazepine receptors, and vasotocin, acting through V1a-like receptors, stimulate the production of neurosteroids. Since neurosteroids are implicated in the control of various neurophysiological and behavioral processes, these data suggest that some of the neurophysiological effects exerted by neurotransmitters and neuropeptides may be mediated via the regulation of neurosteroid production.

Serum levels of brain-derived neurotrophic factor and cortisol to sulfate of dehydroepiandrosterone molar ratio associated with clinical response to L-theanine as augmentation of antipsychotic therapy in schizophrenia and schizoaffective disorder patients

OBJECTIVES

L-Theanine (γ-glutamylethylamide) augmentation to antipsychotic therapy ameliorates positive, activation, and anxiety symptoms in schizophrenia and schizoaffective disorder patients. This study examines the association between circulating levels of neurochemical indicators and the beneficial clinical effects of L-theanine augmentation.

METHODS

Serum levels of neurochemical indicators such as brain-derived neurotrophic factor (BDNF), dehydroepiandrosterone (DHEA), its sulfate (DHEAS), cortisol, cholesterol, and insulin were monitored in 40 schizophrenia and schizoaffective disorder patients during an 8-week, double-blind, randomized, placebo-controlled trial with L-theanine (400 mg/d). Multiple regression analysis was applied for searching association between improvement in symptom scores and changes in circulating levels of neurochemical indicators for an 8-week trial.

RESULTS

Regression models among L-theanine-treated patients indicate that circulating levels of BDNF and cortisol-to-DHEAS*100 molar ratio were significantly associated with the beneficial clinical effects of L-theanine augmentation. Variability of serum BDNF levels accounted for 26.2% of the total variance in reduction of dysphoric mood and 38.2% in anxiety scores. In addition, the changes in cortisol-to-DHEAS*100 molar ratio accounted for 30% to 34% of the variance in activation factor and dysphoric mood scores and for 15.9% in anxiety scores. Regression models among placebo-treated patients did not reach significant level.

CONCLUSIONS

These preliminary results indicate that circulating BDNF and cortisol-to-DHEAS*100 molar ratio may be involved in the beneficial clinical effects of L-theanine as augmentation of antipsychotic therapy in schizophrenia and schizoaffective disorder patients.

Chronic pain therapy and hypothalamic-pituitary-adrenal axis impairment

Opiates and/or nonsteroidal anti-inflammatory drugs (NSAIDs) are among the most effective therapies for chronic pain, but their prolonged time of use can affect health conditions through physical and psychological side effects. They include the very common gastrointestinal effects and changes that can induce osteoporosis, depression, impaired cognition and a generally poor quality of life, which per se can induce and maintain a chronic painful condition. For this reason it is becoming imperative to expand our knowledge of the interaction of these substances with body functions apparently not directly involved in nociception and pain, such as neuroendocrine functions. The purpose of this study was to determine, in male and female patients suffering from chronic pain, the effect of conventional pain therapy (opiates, NSAIDs) on hypothalamic-pituitary-adrenal (HPA) axis function. This was assessed by measuring the blood levels of adrenal-related hormones (adrenocorticotrophin hormone, ACTH; cortisol; dehydroepiandrosterone, DHEA and dehydroepiandrosterone sulfate, DHEAS). The second purpose of the study was to test the hypothesis that these hormones are associated with the psychological profile shown by the chronic pain patients. The results showed significant changes induced by pain therapy on the HPA axis: ACTH, cortisol, DHEA and DHEAS blood levels decreased in all subjects taking opiates or NSAIDs to treat pain. Moreover these changes showed significant correlations with psychological features of the subjects depending on age and sex.

Age-related changes in plasma dehydroepiandrosterone levels in adults with Down's syndrome and the risk of dementia

People with Down's syndrome (DS) are at high risk of developing early onset dementia. Recent studies suggest a link between age-related decreases in dehydroepiandrosterone (DHEA) concentrations and dementia in the general population. The present study investigates the relationship between DHEA serum levels and age and the risk of dementia in adults with DS. The DHEA plasma concentrations of 67 adults with DS and 65 age-matched controls were determined. Participants with DS were assessed for the presence of dementia using the CAMDEX informant interview. The DHEA plasma concentrations decreased with age in subjects with DS as well as in controls. Age significantly predicted DHEA levels in both groups (B = -0.06, t = -4.536, P < 0.001 in the DS group and B = -0.04, t = -2.928, P < 0.005 in control participants). The mean ± SD DHEA level was 3.47 ± 1.41 μmol/l in controls and 2.79 ± 1.24 μmol/l in participants with DS. This difference was significant (t = -2.981, P < 0.01). Within the DS population, ancova revealed a significant relationship between DHEA concentrations and dementia (F(1,65) = 4.348, P < 0.05). We found that DHEA levels declined significantly with age in people with DS and controls and were lower, in comparison to age-matched controls, in people with DS across all ages studied. Those with DS and evidence of dementia have lower DHEA concentrations than those with DS (controlling for age) but without dementia.

DHEA provides a microenvironment for endometrial stem cells neurogenesis

Recently, transplantation of adult stem cells over embryonic stem cells increased in regenerative medicine. Among the adult stem cells, human endometrium stromal (hEnS) cells are under the strict control of the steroid hormones and have the potential to differentiate into other cell lineages including neural cells. Unfortunately these cells may lose their neurogenic differentiation ability upon extended expansion in cultures. To avoid the back-differentiation, it is important to establish growth conditions that support the rapid proliferation and stable differentiation of hEnS cells over extended periods of time without compromising their neuronal phenotype. Differentiation of transplanted cells is strongly influenced by environmental signals. The steroidal microenvironment of the stem cells plays a major role in controlling neurogenesis in the cultures. Dehydroepiandrosterone (DHEA) administration to the cultures could support this propose. DHEA enhance survival rates of dissociated neurons in cultures. It can activate AKT protein kinase pathway as well as nerve growth factor (NGF) that enhances neurogenesis efficiently. On the other hand it seems that DHEA increase survival rate of neural cells via production of brain derived neurotrophic factor (BDNF), indirectly. BDNF is a mediator product of the DHEA that promotes the differentiation and survival of neurons. Here, we offer that DHEA is a suitable candidate that could provide a microenvironment to stimulate neurogenesis and enhanced survival of newly formed neurons derived from hEnS cells. From the point that DHEA is the most abundant steroid in the body, marketed as a supplement and is increasingly self-prescription we hypothesized that it could be the safe and high available choice. This provides a better insight into the maintenance of neural cells for treatment of a wide variety of neurological diseases such as Alzheimer's and Parkinson's by non-invasively autologous cell therapy by hEnS cells especially in women.

Cortisol and dehydroepiandrosterone-sulphate levels correlate with symptom severity in first-episode psychosis

BACKGROUND

Dehydroepiandrosterone (DHEA) and its sulphate form (DHEA) are neuroactive steroids with antiglucocorticoid properties. An imbalance in the ratio of cortisol to DHEA(S) has been implicated in the pathophysiology of stress-related psychiatric disorders. This study prospectively investigated circulating cortisol, DHEAS and their ratio in first-episode psychosis (FEP) patients compared to healthy controls, and their relationship to perceived stress, psychotic, negative and mood symptoms.

METHODS

Blood cortisol and DHEAS levels were obtained in 39 neuroleptic-naïve or minimally-treated FEP patients and 25 controls. Twenty-three patients and 15 controls received repeat assessments after 12 weeks. Perceived stress was assessed using the Perceived Stress Scale and symptoms were assessed in patients using standard rating scales.

RESULTS

At baseline, no differences were observed in cortisol, DHEAS or the cortisol/DHEAS ratio between patients and controls. There were also no group differences in the change in these biological variables during the study period. Within FEP patients, decreases in cortisol and the cortisol/DHEAS ratio over time were directly related to the improvement in depression (r = 0.45; p = 0.031, r = 0.52; p = 0.01), negative (r = 0.51; p = 0.006, r = 0.55; p = 0.008) and psychotic symptoms (cortisol only, r = 0.53; p = 0.01). Perceived stress significantly correlated with DHEAS (r = 0.51; p = 0.019) and the cortisol/DHEAS ratio (r = -0.49; p = 0.024) in controls, but not patients, possibly reflecting an impaired hormonal response to stress in FEP patients.

CONCLUSIONS

These findings further support the involvement of the stress system in the pathophysiology of psychotic disorders, with implications for treatment strategies that modulate these neurosteroids.

Corticosterone and dehydroepiandrosterone have opposing effects on adult neuroplasticity in the avian song control system

Chronic elevations in glucocorticoids can decrease the production and survival of new cells in the adult brain. In rat hippocampus, supraphysiological doses of dehydroepiandrosterone (DHEA; a sex steroid precursor synthesized in the gonads, adrenals, and brain) have antiglucocorticoid properties. With male song sparrows (Melospiza melodia), we examined the effects of physiological doses of corticosterone, the primary circulating glucocorticoid in birds, and DHEA on adult neuroplasticity. We treated four groups of nonbreeding sparrows for 28 days with empty (control), corticosterone, DHEA, or corticosterone + DHEA implants. Subjects were injected with BrdU on days 3 and 4. In HVC, a critical song control nucleus, corticosterone and DHEA had independent, additive effects. Corticosterone decreased, whereas DHEA increased, HVC volume, NeuN(+) cell number, and BrdU(+) cell number. Coadministration of DHEA completely reversed the neurodegenerative effects of chronic corticosterone treatment. In an efferent target of HVC, the robust nucleus of the arcopallium (RA), DHEA increased RA volume, but this effect was blocked by coadministration of corticosterone. There were similar antagonistic interactions between corticosterone and DHEA on BrdU(+) cell number in the hippocampus and ventricular zone. This is the first report on the effects of corticosterone treatment on the adult song control circuit, and HVC was the most corticosterone-sensitive song nucleus examined. In HVC, DHEA is neuroprotective and counteracts several pronounced effects of corticosterone. Within brain regions that are particularly vulnerable to corticosterone, such as the songbird HVC and rat hippocampus, DHEA appears to be a potent native antiglucocorticoid.

Dehydroepiandrosterone effects on Akt signaling modulation in central nervous system of young and aged healthy rats

Dehydroepiandrosterone (DHEA) is a steroid synthesized in adrenal cortex as well as in the nervous system. DHEA effects on central nervous system (CNS) have been associated with several brain functions such as marked neurotrophic and neuroprotective activity. DHEA plasma concentration decreases steadily with aging and studies have reported an inverse correlation between levels of DHEA and neurological diseases age-associated. Nonetheless, its mechanisms of action are not yet fully understood. Akt signaling pathway is one protein kinase which has been related to be DHEA modulated. The goal of this study was to investigate whether short-term (6 or 24h) or chronic (5 weeks) DHEA treatment modulates Akt in CNS of adult (3 months) and aged (18 and 24 months) healthy rats. Hypothalamus and hippocampus homogenates were prepared to quantify total-Akt and phosphorylated Akt at Ser(473) (pAkt). The results here presented have shown that acute (50mg/kg) and chronic (10mg/kg) DHEA injections modulate total and pAkt levels. This effect was dose and time-dependent as well as age and tissue-dependent. In addition, the age variable also intervenes on total and pAkt levels expression independently of DHEA treatment.

Allopregnanolone levels are reduced in temporal cortex in patients with Alzheimer's disease compared to cognitively intact control subjects

The neurosteroid allopregnanolone has pronounced neuroprotective actions, increases myelination, and enhances neurogenesis. Evidence suggests that allopregnanolone dysregulation may play a role in the pathophysiology of Alzheimer's disease (AD) and other neurodegenerative disorders. Our prior data demonstrate that allopregnanolone is reduced in prefrontal cortex in male patients with AD compared to male cognitively intact control subjects, and inversely correlated with neuropathological disease stage (Braak and Braak). We therefore determined if allopregnanolone levels are also reduced in AD patients compared to control subjects in temporal cortex, utilizing a larger set of samples from both male and female patients. In addition, we investigated if neurosteroids are altered in subjects who are APOE4 allele carriers. Allopregnanolone, dehydroepiandrosterone (DHEA), and pregnenolone levels were determined in temporal cortex postmortem samples by gas chromatography/mass spectrometry, preceded by high performance liquid chromatography (40 subjects with AD/41 cognitively intact control subjects). Allopregnanolone levels are reduced in temporal cortex in patients with AD (median 2.68 ng/g, n=40) compared to control subjects (median 5.64 ng/g, n=41), Mann-Whitney p=0.0002, and inversely correlated with Braak and Braak neuropathological disease stage (Spearman r=-0.38, p=0.0004). DHEA and pregnenolone are increased in patients with AD compared to control subjects. Patients carrying an APOE4 allele demonstrate reduced allopregnanolone levels in temporal cortex (Mann-Whitney p=0.04). In summary, our findings indicate that neurosteroids are altered in temporal cortex in patients with AD and related to neuropathological disease stage. In addition, the APOE4 allele is associated with reduced allopregnanolone levels. Neurosteroids may be relevant to the neurobiology and therapeutics of AD.

Pregnenolone, dehydroepiandrosterone, and schizophrenia: alterations and clinical trials

Neurosteroids, such as pregnenolone (PREG), dehydroepiandrosterone (DHEA), and their sulfates (PREGS and DHEAS) are reported to have a modulatory effect on neuronal excitability and synaptic plasticity. They also have many other functions associated with neuroprotection, response to stress, mood regulation, and cognitive performance. Furthermore, these neurosteroids have been linked to, and their levels are altered in, neuropsychiatric disorders. This review highlights what is currently known about the metabolism and mode of action of PREG and DHEA, as well as about alterations of these neurosteroids in schizophrenia. This review also provides substantial information about clinical trials with DHEA and PREG augmentation with of antipsychotic agents in schizophrenia.

Neurocognitive deficits in schizophrenia are associated with alterations in blood levels of neurosteroids: a multiple regression analysis of findings from a double-blind, randomized, placebo-controlled, crossover trial with DHEA

BACKGROUND

While neurosteroids exert multiple effects in the central nervous system, their associations with neurocognitive deficits in schizophrenia are not yet fully understood. The purpose of this study was to identify the contribution of circulating levels of dehydroepiandrosterone (DHEA), its sulfate (DHEAS), androstenedione, and cortisol to neurocognitive deficits through DHEA administration in schizophrenia.

METHODS

Data regarding cognitive function, symptom severity, daily doses, side effects of antipsychotic agents and blood levels of DHEA, DHEAS, androstenedione and cortisol were collected among 55 schizophrenia patients in a double-blind, randomized, placebo-controlled, crossover trial with DHEA at three intervals: upon study entry, after 6weeks of DHEA administration (200mg/d), and after 6weeks of a placebo period. Multiple regression analysis was applied for predicting sustained attention, memory, and executive function scores across three examinations controlling for clinical, treatment and background covariates.

RESULTS

Findings indicated that circulating DHEAS and androstenedione levels are shown as positive predictors of cognitive functioning, while DHEA level as negative predictor. Overall, blood neurosteroid levels and their molar ratios accounted for 16.5% of the total variance in sustained attention, 8-13% in visual memory tasks, and about 12% in executive functions. In addition, effects of symptoms, illness duration, daily doses of antipsychotic agents, side effects, education, and age of onset accounted for variability in cognitive functioning in schizophrenia.

CONCLUSIONS

The present study suggests that alterations in circulating levels of neurosteroids and their molar ratios may reflect pathophysiological processes, which, at least partially, underlie cognitive dysfunction in schizophrenia.

Adrenocortical responsiveness to infusions of physiological doses of ACTH is not altered in posttraumatic stress disorder

Early studies of posttraumatic stress disorder (PTSD) reported that abnormal function of the hypothalamic–pituitary–adrenocortical (HPA) system was associated with the disorder. However, subsequent studies attempting to identify a specific aspect of HPA dysfunction that characterizes PTSD have been marked by considerable inconsistency of results. A facet of HPA regulation that has been considered but not definitively investigated is the possibility that the responsiveness of the adrenal cortex to physiological concentrations of adrenocorticotropin (ACTH) is diminished in PTSD. Relationships between PTSD and the adrenal androgen dehydroepiandrosterone (DHEA) have also been postulated. In this study we investigated the magnitude and time course of changes in concentrations of plasma cortisol and DHEA in response to bolus infusions of physiological doses of ACTH _1–24 in PTSD patients and control subjects. We found no evidence for PTSD-related alterations in cortisol or DHEA secretion in response to stimulation by low doses of ACTH and conclude that adrenocortical responsiveness is normal in PTSD. Results from this and other studies suggest that the occurrence of defects in HPA function in PTSD may be specific responses to particular combinations of trauma type, genetic susceptibility, and individual history.

Dehydroepiandrosterone sulfate and cognitive function in the elderly: The InCHIANTI Study

DHEA and its sulfate derivative (DHEAS) decline with age. The decline in DHEAS levels has been associated with many physiological impairments in older persons including cognitive dysfunction. However, data regarding the possible relationship between DHEAS and cognition are scant. We investigated whether DHEAS levels are associated with presence and development of lower cognitive function measured by the Mini Mental State Examination (MMSE) in older men and women. One thousand and thirty-four residents aged > or =65 yr of the InCHIANTI Study with data available on DHEAS and MMSE were randomly selected. MMSE was administered at baseline and 3 yr later. Among these, 841 completed a 3-yr follow-up. Parsimonious models obtained by backward selection from initial fully-adjusted models were used to identify independent factors associated with MMSE and DHEAS. The final analysis was performed in 755 participants (410 men and 345 women) with MMSE score > or =21. A significant age-related decline of both DHEAS levels (p<0.001) and MMSE score (p<0.001) was found over the 3-yr follow-up. At enrolment, DHEAS was significantly and positively associated with MMSE score, independently of age and other potential confounders (beta+/-SE 0.003+/-0.001, p<0.005). Low baseline DHEAS levels were predictive of larger decline of MMSE and this relationship was significant after adjusting for covariates (beta+/-SE -0.004+/-0.002, p<0.03). Our data show a significant and positive association between DHEAS and cognitive function, assessed by MMSE test. Low DHEAS levels predict accelerated decline in MMSE score during the 3-yr follow-up period.

Relationships among plasma dehydroepiandrosterone and dehydroepiandrosterone sulfate, cortisol, symptoms of dissociation, and objective performance in humans exposed to underwater navigation stress

BACKGROUND

A growing body of research has provided evidence that dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEAS) are involved in an organism's response to stress and that it may provide beneficial behavioral and neurotrophic effects.

METHODS

This study investigated plasma DHEA and DHEAS, cortisol, psychological symptoms of dissociation, and military performance in 41 healthy active duty subjects enrolled in the military Combat Diver Qualification Course (CDQC).

RESULTS

Baseline values of DHEA and DHEAS were significantly and positively predictive of superior performance in the underwater navigation exam; in addition, DHEA and DHEAS were significantly and negatively related to stress-induced symptoms of dissociation during performance of the task. Similarly, participants who reported fewer symptoms of dissociation exhibited superior military performance and increased levels of DHEA after the test.

CONCLUSIONS

These data provide prospective, empiric evidence that DHEA and DHEAS are associated with superior stress tolerance, fewer symptoms of dissociation, and superior, objectively assessed, military performance.

Gene expression profiling of lymphoblasts from autistic and nonaffected sib pairs: altered pathways in neuronal development and steroid biosynthesis

Despite the identification of numerous autism susceptibility genes, the pathobiology of autism remains unknown. The present “case-control” study takes a global approach to understanding the molecular basis of autism spectrum disorders based upon large-scale gene expression profiling. DNA microarray analyses were conducted on lymphoblastoid cell lines from over 20 sib pairs in which one sibling had a diagnosis of autism and the other was not affected in order to identify biochemical and signaling pathways which are differentially regulated in cells from autistic and nonautistic siblings. Bioinformatics and gene ontological analyses of the data implicate genes which are involved in nervous system development, inflammation, and cytoskeletal organization, in addition to genes which may be relevant to gastrointestinal or other physiological symptoms often associated with autism. Moreover, the data further suggests that these processes may be modulated by cholesterol/steroid metabolism, especially at the level of androgenic hormones. Elevation of male hormones, in turn, has been suggested as a possible factor influencing susceptibility to autism, which affects ∼4 times as many males as females. Preliminary metabolic profiling of steroid hormones in lymphoblastoid cell lines from several pairs of siblings reveals higher levels of testosterone in the autistic sibling, which is consistent with the increased expression of two genes involved in the steroidogenesis pathway. Global gene expression profiling of cultured cells from ASD probands thus serves as a window to underlying metabolic and signaling deficits that may be relevant to the pathobiology of autism.

Corticosterone and dehydroepiandrosterone in songbird plasma and brain: effects of season and acute stress

Prolonged increases in plasma glucocorticoids can exacerbate neurodegeneration. In rats, these neurodegenerative effects can be reduced by dehydroepiandrosterone (DHEA), an androgen precursor with anti-glucocorticoid actions. In song sparrows, season and acute restraint stress affect circulating levels of corticosterone and DHEA, and the effects of stress differ in plasma collected from the brachial and jugular veins. Jugular plasma is an indirect index of the neural steroidal milieu. Here, we directly measured corticosterone and DHEA in several brain regions and jugular plasma, and examined the effects of season and acute restraint stress (30 min) (n = 571 samples). Corticosterone levels were up to 10x lower in brain than in jugular plasma. In contrast, DHEA levels were up to 5x higher in brain than in jugular plasma and were highest in the hippocampus. Corticosterone and DHEA concentrations were strongly seasonally regulated in plasma but, surprisingly, not seasonally regulated in brain. Acute stress increased corticosterone levels in plasma and brain, except during the molt, when stress unexpectedly decreased corticosterone levels in the hippocampus. Acute stress increased DHEA levels in plasma during the molt but had no effects on DHEA levels in brain. This is the first study to measure (i) corticosterone or DHEA levels in the brain of adult songbirds and (ii) seasonal changes in corticosterone or DHEA levels in the brain of any species. These results highlight several critical differences between systemic and local steroid concentrations and the difficulty of using circulating steroid levels to infer local steroid levels within the brain.

Evolution of neuroendocrine mechanisms linking attachment and life history: The social neuroendocrinology of middle childhood

An extended period of childhood and juvenility is a distinctive aspect of human life history. This stage appears to be important for learning cultural, social, and ecological skills that help prepare the child for the adult socio-competitive environment. The unusual pattern of adrenarche in humans (and chimpanzees) may facilitate adaptive modification of the neurobiological mechanisms that underpin reproductive strategies. Longitudinal monitoring of DHEA/S in naturalistic context could provide important new insights into these aspects of child development.

Neurobiological and neuropsychiatric effects of dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS)

DHEA and DHEAS are steroids synthesized in human adrenals, but their function is unclear. In addition to adrenal synthesis, evidence also indicates that DHEA and DHEAS are synthesized in the brain, further suggesting a role of these hormones in brain function and development. Despite intensifying research into the biology of DHEA and DHEAS, many questions concerning their mechanisms of action and their potential involvement in neuropsychiatric illnesses remain unanswered. We review and distill the preclinical and clinical data on DHEA and DHEAS, focusing on (i) biological actions and putative mechanisms of action, (ii) differences in endogenous circulating concentrations in normal subjects and patients with neuropsychiatric diseases, and (iii) the therapeutic potential of DHEA in treating these conditions. Biological actions of DHEA and DHEAS include neuroprotection, neurite growth, and antagonistic effects on oxidants and glucocorticoids. Accumulating data suggest abnormal DHEA and/or DHEAS concentrations in several neuropsychiatric conditions. The evidence that DHEA and DHEAS may be fruitful targets for pharmacotherapy in some conditions is reviewed.

Effects of sex, gonadal hormones, and augmented acoustic environments on sensorineural hearing loss and the central auditory system: insights from research on C57BL/6J mice

Mice of the C57BL/6J (B6) inbred strain exhibit genetic progressive sensorineural hearing loss and have been widely used as a model of adult-onset hearing loss and presbycusis. Males and females exhibit similar degrees of hearing loss until about 3 months of age, after which, the loss accelerates in females. This paper reviews research on how the B6 auditory system is affected by sex, gonadectomy (i.e., a reduction of gonadal hormone levels), and nightly exposure to moderately intense augmented acoustic environments (AAEs) - a low-frequency noise band (LAAE) or high-frequency band (HAAE). Several findings indicate a negative effect of ovarian hormones on the female B6 auditory system. Whereas the sex difference in high-frequency hearing loss was not significantly affected by gondadectomies, the female disadvantage in ABR thresholds at lower frequencies was erased by ovariectomy. Moreover, exposure to the LAAE or HAAE caused losses of hair cells that were more severe in intact females than in ovariectomized females or in males. Finally, intact females had more severe loss of neurons in the low-frequency region of the anterior ventral cochlear nucleus (AVCN) than other groups. In contrast, the presence of androgens had beneficial effects. Loss of hair cells and AVCN neurons after AAE exposure were more severe in orchidectomized males than in intact males. Ideas, hypotheses, and potential mechanisms concerning the findings are discussed.

Cerebrospinal fluid dehydroepiandrosterone levels are correlated with brain dehydroepiandrosterone levels, elevated in Alzheimer's disease, and related to neuropathological disease stage

OBJECTIVE

It is currently unknown whether cerebrospinal fluid (CSF) neurosteroid levels are related to brain neurosteroid levels in humans. CSF and brain dehydroepiandrosterone (DHEA) levels are elevated in patients with Alzheimer's disease (AD), but it is unclear whether CSF DHEA levels are correlated with brain DHEA levels within the same subject cohort. We therefore determined DHEA and pregnenolone levels in AD patients (n = 25) and cognitively intact control subjects (n = 16) in both CSF and temporal cortex.

DESIGN

DHEA and pregnenolone levels were determined by gas chromatography/mass spectrometry preceded by HPLC. Frozen CSF and temporal cortex specimens were provided by the Alzheimer's Disease Research Center at Duke University Medical Center. Data were analyzed by Mann-Whitney U test statistic and Spearman correlational analyses.

RESULTS

CSF DHEA levels are positively correlated with temporal cortex DHEA levels (r = 0.59, P < 0.0001) and neuropathological disease stage (Braak and Braak) (r = 0.42, P = 0.007). CSF pregnenolone levels are also positively correlated with temporal cortex pregnenolone levels (r = 0.57, P < 0.0001) and tend to be correlated with neuropathological disease stage (Braak) (r = 0.30, P = 0.06). CSF DHEA levels are elevated (P = 0.032), and pregnenolone levels tend to be elevated (P = 0.10) in patients with AD, compared with cognitively intact control subjects.

CONCLUSIONS

These findings indicate that CSF DHEA and pregnenolone levels are correlated with temporal cortex brain levels of these neurosteroids and that CSF DHEA is elevated in AD and related to neuropathological disease stage. Neurosteroids may thus be relevant to the pathophysiology of AD.

Effects of neurosteroids on hydrogen peroxide- and staurosporine-induced damage of human neuroblastoma SH-SY5Y cells

Neurosteroids are important regulators of central nervous system function and may be involved in processes of neuronal cell survival. This study was undertaken to test the effect of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), pregnenolone (PGL), pregnenolone sulfate (PGLS), and allopregnanolone (Allo) on hydrogen peroxide- and staurosporine-induced toxicity in SH-SY5Y cells. It has been found that DHEAS inhibited the hydrogen peroxide toxicity in a concentration-dependent manner, whereas DHEA was active only at higher doses. PGL and PGLS showed neuroprotective effects only at the lowest concentration. Allo had no significant effect on hydrogen peroxide-evoked lactate dehydrogenase release and at the highest concentration aggravated its toxic effects. Next part of this study evaluated neurosteroid effects on staurosporine-induced apoptosis. DHEAS, DHEA, and PGL significantly antagonized effects of staurosporine on both caspase-3 activity and mitochondrial membrane potential. PGLS and Allo inhibited the staurosporine-induced changes in both apoptotic parameters only at the lowest concentration. Antiapoptotic properties of neurosteroids were positively verified by Hoechst staining. Furthermore, as shown by calcein assay, DHEA, DHEAS, and PGL increased viability of staurosporine-treated cells, and these effects were attenuated by specific inhibitors of phosphatidylinositol 3-kinase (PI3-K) and extracellular signal-regulated protein kinase (ERK)-mitogen activated protein kinase (MAPK). These data indicate that neurosteroids prevent SH-SY5Y cell damage related to oxidative processes and activation of mitochondrial apoptotic pathway. Moreover, neuroprotective effects of DHEA, DHEAS seem to depend on PI3-K and ERK/MAPK signaling pathways. It can be suggested that, at physiological concentrations, all studied neurosteroids participate in the inhibition of neuronal apoptosis, but with various potencies.

Dehydroepiandrosterone and corticosterone are regulated by season and acute stress in a wild songbird: jugular versus brachial plasma

Stress has well-known effects on adrenal glucocorticoid secretion, and chronic elevation of glucocorticoids can have detrimental effects on the brain. Dehydroepiandrosterone (DHEA), an androgen precursor synthesized in the adrenal glands or the brain itself, has anti-glucocorticoid properties, but little is known about the role of DHEA in the stress response, particularly in the brain. Here, we measured the effects of acute restraint on circulating corticosterone (CORT) and DHEA levels in wild song sparrows. Blood was collected from either the brachial or jugular vein. In songbirds, jugular plasma is enriched with neurally synthesized steroids, and therefore, jugular plasma is an indirect index of the neural steroidal milieu. Subjects were sampled during four times of year: breeding, molt, early nonbreeding, and mid-nonbreeding. Baseline CORT and DHEA levels showed similar seasonal changes; both steroids were elevated during the breeding season. Baseline CORT and DHEA levels were similar in jugular and brachial plasma. Acute stress had robust effects on CORT and DHEA that were season specific and vein specific. For CORT, during the molt, stress increased jugular CORT more than brachial CORT. For DHEA, during the breeding season, stress decreased jugular DHEA but not brachial DHEA. During the molt, stress increased jugular DHEA but not brachial DHEA. Acute stress did not affect brachial DHEA. These data suggest that acute stress specifically affects the balance between DHEA synthesis and metabolism in the brain. Furthermore, these results suggest that CORT and DHEA are locally synthesized in the brain during molt, when systemic levels of CORT and DHEA are low.

Temporal effects of dehydroepiandrosterone sulfate on memory formation in day-old chicks

Dehydroepiandrosterone sulfate (DHEAS) has been shown to enhance memory retention in different animal models and in various learning paradigms. In the present study, we investigated the effect of peripherally administered DHEAS on the acquisition, consolidation and retention of memory using a weak version of the one-trial passive avoidance task in day-old chicks. Intraperitoneally administered DHEAS (20 mg/kg) either 30 min before or 30 min and 4.5 h after training on the weakly aversive stimulus, enhanced recall at 24 h following training, suggesting a potentiation of not only the acquisition but also the early and late phases of memory consolidation. In contrast, when DHEAS was administered at 30 min prior to the 24 h retention test there was no memory enhancement, indicating a lack of effect on memory retrieval. Memory recall was unaltered when DHEAS was administered at 30 min before training in a control group trained on a strongly aversive stimulus, confirming memory-specific effects. Interestingly, the memory enhancement appeared to be sex-specific as male chicks showed higher recall than females. These findings provide further evidence that DHEAS enhances memory and may be involved in the temporal cascade of long-term memory formation.

WITHDRAWN: Dehydroepiandrosterone (DHEA) supplementation for cognitive function

BACKGROUND

In view of the theoretical rationale for beneficial effects of DHEA and DHEAS on cognitive function in ageing and dementia, we have undertaken a thorough investigation of well-conducted studies in this area. This will provide a basis for confirmation of any effect of DHEA/S administration in humans in properly controlled trials. The review will also provide a scientific basis for effective dosage, acceptable route and duration of administration, and side effect profiles. This review is especially pertinent at this time as DHEA is currently being sold in large quantities in health food stores, particularly in the USA. In some cases the recommended dose is different for men and women (50mg/day for men and 25mg/day for women) and the basis for this recommendation needs to be explored.

OBJECTIVES

To establish whether administration of DHEA, or its sulphate, DHEAS, improves cognitive function or reduces the rate of decline of cognitive function in normal older adults or in individuals with dementia.

SEARCH STRATEGY

Relevant electronic databases, journals, personal communications and conference abstracts were searched for randomised controlled trials investigating the effects of DHEA/S on cognition in older adults.

SELECTION CRITERIA

All relevant randomised controlled trials of DHEA/S were considered for inclusion in the review.

DATA COLLECTION AND ANALYSIS

Data for the specified outcomes were independently extracted by two reviewers (FAH & JvN) and cross-checked. Any discrepancies were discussed and resolved. No data pooling was undertaken owing to the lack of availability of the relevant statistics.

MAIN RESULTS

There are four included studies, three cognition in normal older people, and Barnhart 1999 in perimenopausal women with decreased well-being. There were no studies in dementia. There were a few significant findings. Wolf 1997 found significant improvement following DHEA compared with placebo in both immediate recall (MD 0.8, 95% CI 0.16, 1.44) and delayed recall (MD 0.9, 95% CI 0.09, 1.71) of a visual memory test in women, estimated in a crossover trial after 2 weeks of treatment with each of DHEA and placebo. However there was no significant improvement in men, nor a significant effect on a verbal memory test. There was also no significant effect on four other cognitive tests. Wolf 1998 (2) found that placebo group performance deteriorated significantly on a test of selective attention following a psychosocial stressor (p<0.05), while deterioration was not evident in the DHEA group (p=0.85) after two weeks of treatment. However, when compared to placebo, DHEA produced a significant impairment on a visual memory test (p<0.01) following the stressor. No significant effect was found on a third cognitive task. Effects were not found on tasks when administered in the absence of a stressor. Barnhart 1999 employed three cognitive measures and found no significant effect of DHEA compared with placebo at 3 months. Findings to date suggest that DHEA replacement seems to be well tolerated with an absence of significant side-effects.

AUTHORS' CONCLUSIONS

The data offer no support at present for an improvement in memory or other aspects of cognitive function following DHEA treatment in normal older people. In view of the growing public enthusiasm for DHEA supplementation, particularly in the USA, and the possibility that any neuroprotective effect of DHEA/S may only be evident in the long term, there is a need to undertake high quality trials in which the duration of DHEA treatment is longer than one year, and the number of participants is large enough to detect effects if they exist.Recently, trials of DHEA supplementation in Alzheimer's Disease (USA), post-menopausal women (USA), normal older men (UK), and a one-year trial in normal older men and women (France) have been completed. As soon as the results are available these studies will be included in the review.

Therapies for adrenal insufficiency

Adrenal insufficiency is a life-threatening disorder. In the treatment of adrenal insufficiency, it is essential to administer the optimal medication at the optimal dose. Glucocorticoids are the main therapeutic approach in all forms of adrenal insufficiency. The recommended protocol for maintenance therapy is 15-25 mg of hydrocortisone, divided into two or three separate doses. Patients with primary adrenal insufficiency generally receive mineralocorticoid replacement comprised of fludrocortisone 0.05-0.2 mg/day. Recently, dehydroepiandrosterone has been proposed as a new therapeutic approach, despite the lack of strong evidence for beneficial effects. Additional glucocorticoid supplementation should be administered in stressful states. During critical illness, inadequate or no temporary increase in the dose of the replacement glucocorticoid can lead to acute adrenal failure. When acute adrenal failure occurs, it becomes necessary to administer intravenous hydrocortisone.

Gender differences of acute and chronic administration of dehydroepiandrosterone in rats submitted to the forced swimming test

Previous pre-clinical and clinical studies investigating the antidepressant potential of DHEA revealed conflicting results. In this study, the effects of exogenous DHEA on performance in the forced swimming test (FST) were examined in male and female Wistar rats in different phases of the estrous cycle. Furthermore, the effects of treatment and of the FST, on corticosterone and DHEA serum levels were investigated. Acute administration of DHEA (2 mg/kg) significantly increased freezing only in proestrus female rats. Similarly, the chronic administration of DHEA (2 mg/kg) increased freezing duration and decreased climbing behavior but only in females in diestrus II compared to those given vehicle. These results demonstrate that chronically administered DHEA induces a depressant-like effect, and this effect is sex dependent. There was no direct correlation between corticosterone levels or the corticosterone/DHEA ratio and the behaviors studied. After the FST, serum DHEA and corticosterone levels were increased, with females showing higher DHEA levels than males. Nevertheless, corticosterone levels were unaltered with chronic procedure; an effect that was independent of sex and treatment. These findings are relevant for research examining alternative treatment for depression and may elucidate the gender differences involved in stress-related diseases.

State and trait related predictors of serum cortisol to DHEA(S) molar ratios and hormone concentrations in schizophrenia patients

OBJECTIVE

In previous studies we have demonstrated high serum molar ratios of cortisol to dehydroepiandrosterone (DHEA) and its sulfate ester (DHEAS) [together abbreviated DHEA(S)], and the value of both cortisol/DHEA(S) molar ratios for prediction of responsivity to antipsychotic treatment in schizophrenia patients. The present study aimed to examine the contribution of anxiety, and severity of symptoms to the prediction of serum cortisol, DHEA(S) levels and two molar ratios across three examinations.

METHOD

Serum concentrations of cortisol and DHEA(S)were examined in 43 schizophrenia inpatients and in 20 age matched healthy controls at baseline, and after 2 and 4 weeks. The Positive and Negative Symptom Scale and the State-Trait Anxiety Inventory scores were used as independent variables for multiple regression analysis.

RESULTS

Despite clinical improvement during the study period cortisol/DHEA(S) molar ratios were found persistently elevated as compared to healthy controls. Multiple regression analysis revealed that across three examinations cortisol/DHEA(S) molar ratios negatively associated with trait-anxiety (partial R(2)=7-14%) rather than with negative symptoms (partial R(2)=3-6%). Age and age of onset account for 12.7% for variability of cortisol/DHEAS ratio. Serum cortisol concentrations are predicted by trait and state-anxiety, activation symptoms and daily doses of antipsychotics. A small portion of variability in serum DHEA levels (R(2)=9%) is associated with symptom severity, while DHEAS levels were predicted by age at examination and age of onset.

CONCLUSION

Elevated serum cortisol/DHEA(S) molar ratios were attributed to trait-anxiety and age rather than to clinical symptoms. The findings may indicate persistent dysfunction of the hypothalamic-pituitary-adrenal axis that is independent of the patients' clinical state.

Adrenarche and the evolution of human life history

Adrenarche, the prepubertal onset of adrenal production of dehydroepiandrosterone sulfate (DHEAS), is a distinctive aspect of the human life course. Yet its evolutionary origins remain unexplained. Production of DHEAS is associated with the development of the zona reticularis, a novel histological layer within the adrenal gland, derived from the fetal adrenal gland, and associated with primates more generally. Evidence that DHEAS is a neurosteroid, together with the fact that increases in DHEAS parallel patterns of cortical maturation from approximately age 6 years to the mid-20s, suggests that DHEAS may play an important role in extended brain maturation among humans. DHEAS has demonstrated effects on mood in humans, and acts at neuron receptor sites. I suggest three ways in which DHEAS may play a role in human brain maturation: 1) increasing activity of the amgydala; 2) increasing activity of the hippocampus; and 3) promoting synaptogenesis within the cortex. I propose that associated changes in fearfulness and anxiety, and memory, could act to increase social interaction with nonfamiliar individuals and shape cognitive development. Comparison with the African apes suggests that the timing of adrenarche in chimpanzees may be similar to that in humans, though the full course of age-related changes in DHEAS and their relationship to reproductive and brain maturation are not clear. The role of DHEAS as a physiological mechanism supporting increased brain development, extended life span, and decreased sexual dimorphism is most compatible with Kaplan et al.'s (2000) theory of the evolution of human life history and intergenerational transfers.

The neurosteroid allopregnanolone is reduced in prefrontal cortex in Alzheimer's disease

BACKGROUND

Few data are currently available investigating neurosteroids (NS) in Alzheimer's disease (AD). The NS allopregnanolone may be decreased in serum and plasma in patients with AD, but it is unclear if allopregnanolone is also reduced in brain. Because a number of NS exhibit neuroprotective effects and impact cognitive performance in rodent models, these molecules may be relevant to the pathophysiology of neurodegenerative disorders. We therefore investigated prefrontal cortex (PFC) NS levels in AD.

METHODS

Neurosteroid levels (allopregnanolone, pregnenolone, dehydroepiandrosterone [DHEA]) were determined in postmortem PFC in 14 male subjects with AD and 15 cognitively intact male control subjects by gas chromatography/mass spectrometry preceded by high-performance liquid chromatography purification.

RESULTS

Subjects with AD exhibit significant reductions in allopregnanolone compared with cognitively intact control subjects (median levels = 2.50 ng/g vs. 5.59 ng/g, respectively; p = .02). Allopregnanolone levels are inversely correlated with neuropathological disease stage (Braak), r = -.49, p = .007. Median DHEA levels are elevated in subjects with AD (p = .01).

CONCLUSIONS

Subjects with AD demonstrate significant reductions in PFC allopregnanolone levels, a finding that may be relevant to neuropathological disease stage severity. Neurosteroids may have utility as candidate biomarkers in AD.

Dehydroepiandrosterone (DHEA) supplementation for cognitive function in healthy elderly people

BACKGROUND

In view of the theoretical possibility of beneficial effects of DHEA or DHEAS in retarding age-associated deterioration in cognitive function, we have reviewed studies in this area.

OBJECTIVES

To establish whether administration of DHEA, or its sulphate, DHEAS, improves cognitive function or reduces the rate of decline of cognitive function in normal older adults.

SEARCH STRATEGY

Trials were identified from a last updated search of the Specialized Register of the Cochrane Dementia and Cognitive Improvement Group on 10 October 2005 using the terms dhea*, prasterone, dehydroepiandrosterone*. In addition MEDLINE, EMBASE, PsycINFO and CINAHL were searched to find trials with volunteers who had no or minor memory complaints. Relevant journals, personal communications and conference abstracts were searched for randomized controlled trials investigating the effects of DHEA/S on cognition in older adults.

SELECTION CRITERIA

All randomized placebo-controlled trials enrolling people aged over 50 without dementia and to whom DHEA/S in any dosage was administered for more than one day were considered for inclusion in the review.

DATA COLLECTION AND ANALYSIS

Data for the specified outcomes were independently extracted by two reviewers (JGE and RM) and cross-checked. Any discrepancies were discussed and resolved. No data pooling was undertaken owing to the lack of availability of the relevant statistics.

MAIN RESULTS

Only three studies provided results from adequate parallel-group data. Barnhart 1999 enrolled perimenopausal women with complaints of decreased well-being and, using three cognitive measures, found no significant effect of DHEA compared with placebo at 3 months. Wolf 1998b enrolled 75 healthy volunteers (37 women and 38 men aged 59-81) in a study of the effect of DHEA supplements on cognitive impairment induced by stress; after two weeks of treatment, placebo group performance deteriorated significantly on a test of selective attention following a psychosocial stressor (p<0.05), while deterioration was not evident in the DHEA group (p=0.85). However, when compared with placebo, DHEA was associated with a significant impairment on a visual memory recall test (p<0.01) following the stressor. No significant effects were found on a third cognitive task. Effects were not found on tasks when administered in the absence of a stressor. van Niekerk 2001 found no effect on cognitive function in 46 men aged 62-76 from three months of DHEA supplementation. DHEA supplements were well tolerated and without significant adverse effects apart from the reduced performance in the visual memory recall test observed in one trial.

AUTHORS' CONCLUSIONS

What little evidence there is from controlled trials does not support a beneficial effect of DHEA supplementation on cognitive function of non demented middle-aged or elderly people. There is no consistent evidence from the controlled trials that DHEA produces any adverse effects. In view of growing public enthusiasm for DHEA supplementation, particularly in the USA, and the theoretical possibility of long-term neuroprotective effects of DHEA/S, there is a need for further high quality trials in which the duration of DHEA treatment is longer than one year, and the number of participants is large enough to provide adequate statistical power.

Cortisol, dehydroepiandrosterone sulphate and dehydroepiandrosterone sulphate/cortisol ratio responses to physical stress in males are influenced by pubertal development

To evaluate the influence of chronological age and pubertal development on the hypothalamus-pituitary-adrenal (HPA) axis response to stress, we studied the possible correlations between male pubertal characteristics and salivary cortisol (C), DHEAS and the DHEAS/C ratio before (pre-stress) and after acute exercise-stress in young male volunteers (no. 87; 13.3+/-2.1 yr). In our overall study population, the mean pre-stress salivary C and DHEAS concentrations, significantly increased after exercise-related stress, whereas the DHEAS/C ratio significantly decreased. Pre-stress salivary C was positively correlated with chronological age, and after-stress salivary C concentration variations were negatively correlated with pubertal stage, mean testis volume and pre-stress salivary DHEAS. Furthermore, salivary DHEAS concentrations and the DHEAS/C ratio, before and after exercise stress, were positively correlated with chronological age, pubertal stage, pre-stress salivary testosterone (T), testis volume and body mass index (BMI). In contrast with late pubertal stages (P4, P5), young individuals at early stages of puberty (P1 to P3) showed higher C increase and lower DHEAS/C ratio after exercise-related stress. In conclusion, since C is also a mediator of stress-related negative effects on health and the DHEAS/C ratio has been hypothesized as an index for the degree to which an individual is buffered against the negative effects of stress, these data might suggest potentially increased stress-related risks at early stages of male puberty.

Clinical correlates of DHEA associated with post-traumatic stress disorder

OBJECTIVE

Increased plasma dehydroepiandrosterone (DHEA) and dehydroepiandrosterone-sulfate (DHEAS) have been demonstrated in post-traumatic stress disorder (PTSD), but the documented beneficial effects of these steroids in enhancing mood and cognition, as well as neuroprotection, suggest their presence in PTSD may be associated with defensive rather than maladaptive effects.

METHOD

We, therefore, examined plasma DHEA, DHEAS, cortisol, and the DHEA/cortisol ratio in 40 male veterans with or without PTSD, and determined their relationships to PTSD symptom severity and symptom improvement.

RESULTS

The PTSD group showed significantly higher plasma DHEA and non-significantly higher DHEAS levels as well as a significantly lower cortisol/DHEA ratio, controlling for age. Regression analyses demonstrated that DHEA and DHEAS levels could be predicted by symptom improvement and coping, whereas the cortisol/DHEA ratio was predicted by severity of childhood trauma and current symptom severity.

CONCLUSION

That greater symptom improvement was related to DHEA levels may suggest for a role for these hormones in modulating recovery from PTSD.

Neurosteroids, neuroactive steroids, and symptoms of affective disorders

Neurosteroids (NS) are steroids synthesized by the brain. Neuroactive steroids (NAS) refers to steroids that, independent of their origin, are capable of modifying neural activities. NAS bind and modulate different types of membrane receptors. The gamma amino butyric acid (GABA) and sigma receptor complexes have been the most extensively studied. Oxidized ring A reduced pregnanes, tetrahydroprogesterone (THP), and tetrahydrodeoxycorticosterone (THDOC) bind to the progesterone intracellular receptor (PR), and in this way can also regulate gene expression. Animal experimentation showed that salient symptoms of depression, viz., anxiety, sleep disturbances, and memory and sexual dysfunctions, are modulated by NAS. In turn, psychotropic drugs modulate NS and NAS levels. NS levels as well as NAS plasma concentrations change in patients with depression syndromes, the levels return to normal baseline with recovery, but normalization is not necessary for successful therapy. Results from current studies on the evolution of nervous systems, including evolutionary developmental biology as well as anatomical and physiological findings, almost preclude a categorical classification of the psychiatric ailments the human brain succumbs to. The persistence in maintaining such essentialist classifications may help to explain why up to now the search for biological markers in psychiatry has been an unrewarding effort. It is proposed that it would be more fruitful to focus on relationships between NAS and symptoms of psychiatric disorders, rather than with typologically defined disorders.

Developing an Agenda for Translational Studies of Resilience and Vulnerability Following Trauma Exposure

Here we outline a translational research agenda for studies of resilience, defined as the process of adapting well in the face of adversity or trauma. We argue that an individual differences approach to the study of resilience, in which the full range of behavioral and biological responses to stress exposure is examined can be applied across human samples (e.g., people who have developed psychopathology versus those who have not; people who have been exposed to trauma versus those who have not) and even, in some cases, across species. We delineate important psychological resilience-related factors including positive affectivity and optimism, cognitive flexibility, coping, social support, emotion regulation, and mastery. Key brain regions associated with stress-related psychopathology have been identified with animal models of fear (e.g., extinction and fear conditioning; memory reconsolidation) and we describe how these regions can be studied in humans using neuroimaging technology. Finally, we cite recent research identifying neuroendocrine markers of resilience and recovery in humans (e.g., neuropeptide Y [NPY], dehydroepiandrosterone [DHEA]) that can also be measured, in some cases, in other species. That exposure to adversity or trauma does not necessarily lead to impairment and the development of psychopathology in all people is an important observation. Understanding why this is so will provide clues for the development of therapeutic interventions for those people who do develop stress-related psychopathology, or even for the prevention of adverse outcomes.