Dehydroepiandosterone and its sulphate enhance memory retention in day-old chicks

Biological effects of iodine, selenium, sulfur citrates in broiler chickens

This study aimed at the assessment of the I, Se, S citrate effect on the organism of broiler chickens. Feeding of chickens of all groups was carried out by using standard balanced feeds – starter, grower, and finish with the use of group feeders placed at the appropriate height from the floor depending on the poultry height. For the chickens of experimental groups, I, Se, S citrate was added to drinking water daily during the 48th day. To the drinking water of chickens of experimental groups different amounts of the citrate solution were added I (200 mg/L), Se (50 mg/L), S (300 mg/L), prepared by the nanotechnology method. Chickens of the II group received the lowest dose of I, Se, S at the rate of 5 μg I/L, 1.25 μg Se/L, 7.5 μg S/L of drinking water, and for poultry of other experimental groups, it was increased by 2 (III), 4 (IV), 6 (V) and 8 (VI) times compared to II group. Coccidiostat "Kokcisan 12%" (KRKA, Slovenia) was added to the starter and grower feed at the stages of its manufacture in quantities of 0.5 kg/t of feed. Coccidiostat was not added to the final feed. During the 48-day technological period, the clinical condition of the poultry was monitored daily by forage and motor activity, safety, and every 7 days – for growth intensity with the individual determination of body weight on a laboratory scale. The investigation of the blood was carried out from the 35th or 48th day during the growing, period and also investigation of the internal organs – liver, heart, spleen, stomach, thymus, and bursa of Fabricius. The increase of cholesterol, triacylglycerols, and albumin in the blood of II, III, and VI chicken groups was established on the 35th day of the experiment, and the reduction of creatinine in III and VI groups. By that time, the effect of highest dose of I, Se, S caused a decrease in the T3 concentration in the blood of chickens in the VI group compared to the I and II groups. In particular, in the blood of chickens of IV, V and VI groups compared to the I, II, III group under these conditions there was a significant increase in the content of urea, Ca, P, cholesterol, as well as albumin – only in IV group on the 48th day. Triacylglycerols’ content increased in the blood serum of chickens in III and IV groups compared to the II and V groups, but in V group – decreased compared to the III, IV groups. The increase in liver, thymus, and heart mass in the II and V chicken groups was noticed and their decrease in the VI group was revealed compared with the control group. Reliable lower coefficients of the body mass of chickens of III and VI groups may indicate a less notable stimulating biological effect of I, Se, S citrate in these doses on liver development than on the whole organism. The addition of I, Se, S citrate to broiler chickens during the period of growing revealed the difference in their biological action in the presence and absence of the Kokcisan 12% in a mixed fodder. A more notable stimulating effect of low dose of I, Se, S citrate on the growth and development on the chickens' organism was established during the withdrawal of coccidiostatics from their diet. The effect may be due to its inhibitory influence on the biological activity of these elements in the first 35 days of growing. In the final period of chicken growing and withdrawal of ionophore Kokcisan from the diet more noticeable changes were revealed in the studied parameters.

Neurosteroids; potential underpinning roles in maintaining homeostasis

The neuroactive steroids which are synthesized in the brain and nervous system are known as "Neurosteroids". These steroids have crucial functions such as contributing to the myelination and organization of the brain connectivity. Under the stressful circumstances, the concentrations of neurosteroid products such as allopregnanolone (ALLO) and allotetrahydrodeoxycorticosterone (THDOC) alter. It has been suggested that these stress-derived neurosteroids modulate the physiological response to stress. Moreover, it has been demonstrated that the hypothalamic-pituitary-adrenal (HPA) axis mediates the physiological adaptation following stress in order to maintain homeostasis. Although several regulatory pathways have been introduced, the exact role of neurosteroids in controlling HPA axis is not clear to date. In this review, we intend to discern specific pathways associated with regulation of HPA axis in which neuroactive steroids have the main role. In this respect, we propose pathways that may be initiated after neurosteroidogenesis in different brain subregions following acute stress which are potentially capable of activating or inhibiting the HPA axis.

Oxidative metabolism of dehydroepiandrosterone (DHEA) and biologically active oxygenated metabolites of DHEA and epiandrosterone (EpiA)--recent reports

Dehydroepiandrosterone (DHEA) is a multifunctional steroid with a broad range of biological effects in humans and animals. DHEA can be converted to multiple oxygenated metabolites in the brain and peripheral tissues. The mechanisms by which DHEA exerts its effects are not well understood. However, evidence that the effects of DHEA are mediated by its oxygenated metabolites has accumulated. This paper will review the panel of oxygenated DHEA metabolites (7, 16 and 17-hydroxylated derivatives) including a number of 5α-androstane derivatives, such as epiandrosterone (EpiA) metabolites. The most important aspects of the oxidative metabolism of DHEA in the liver, intestine and brain are described. Then, this article reviews the reported biological effects of oxygenated DHEA metabolites from recent findings with a specific focus on cancer, inflammatory and immune processes, osteoporosis, thermogenesis, adipogenesis, the cardiovascular system, the brain and the estrogen and androgen receptors.

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.

DHEA and estradiol levels in brain, gonads, adrenal glands, and plasma of developing male and female European starlings

Traditionally, sexual differentiation of the brain was thought to be driven by gonadal hormones, particularly testosterone (T). However, recent studies in songbirds suggest that other steroids may also be important. For example, dehydroepiandrosterone (DHEA) can be synthesized by the gonads, adrenal glands, and/or brain and locally metabolized into T and 17β-estradiol (E(2)). Here, we examined DHEA and E(2) levels in the brain, peripheral tissues, and plasma of wild European starlings (Sturnus vulgaris). In Study 1, samples were collected from males and females at P0 (day of hatch), P6, and P8. In Study 2, samples were collected at P4. At P0, DHEA levels in the diencephalon were higher in males than females. DHEA levels were generally high in the gonads and adrenals, and they were higher in testes than ovaries at P8. Further, E(2) levels were non-detectable in most brain samples, suggesting that DHEA was not metabolized to E(2) or that locally produced E(2) was rapidly inactivated. At P4, DHEA levels in telencephalic regions were lower in males than females. Taken together, these data suggest that sex differences in peripheral DHEA secretion and neural DHEA metabolism at specific ages during development might play a role in sexual differentiation of the songbird brain.

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.

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

Dehydroepiandrosterone (DHEA) is synthesized in the brain and several studies have shown that this steroid is a modulator of synaptic transmission. The effect of DHEA, and its sulfate ester DHEAS, on glutamate and GABA neurotransmission has been extensively studied but some effects on other neurotransmitter systems, such as dopamine, serotonin and nitric oxide, have also been reported. This review summarizes studies showing the effect of DHEA and DHEAS on neurotransmitter systems at different levels (metabolism, release, reuptake, receptor activation), as well as the activation of voltage-gated ion channels and calcium homeostasis, showing the variety of effects that these steroids exert on those systems, allowing the discussion of its mechanisms of action and its relevance to psychiatric disorders.

Sex differences in DHEA and estradiol during development in a wild songbird: Jugular versus brachial plasma

Sexual differentiation of the brain has traditionally been thought to be driven by gonadal hormones, particularly testosterone (T). Recent studies in songbirds and other species have indicated that non-gonadal sex steroids may also be important. For example, dehydroepiandrosterone (DHEA)--a sex steroid precursor that can be synthesized in the adrenal glands and/or brain--can be converted into active sex steroids, such as 17beta-estradiol (E(2)), within the brain. Here, we examine plasma DHEA and E(2) levels in wild developing European starlings (Sturnus vulgaris), from hatch (P0) to fledging (P20). Blood samples were collected from either the brachial vein (n=143) or the jugular vein (n=129). In songbirds, jugular plasma is enriched with neurally-synthesized steroids and, therefore, jugular plasma is an indirect measure of the neural steroidal milieu. Interestingly, brachial DHEA levels were higher in males than females at P4. In contrast, jugular DHEA levels were higher in females than males at P0 and P10. Brachial E(2) levels were higher in males than females at P6. Surprisingly, jugular E(2) levels were not high and showed no sex differences. Also, we calculated the difference between brachial and jugular steroid levels. At several ages, jugular steroid levels were lower than brachial levels, particularly in males, suggesting greater neural metabolism of circulating DHEA and E(2) in males than females. At a few ages, jugular steroid levels were higher than brachial levels, suggesting neural secretion of DHEA or E(2) into the general circulation. Taken together, these data suggest that DHEA may play a role in brain sexual differentiation in songbirds.

Analysis of steroids in songbird plasma and brain by coupling solid phase extraction to radioimmunoassay

It is a common practice to extract steroids from plasma, serum, or tissue samples prior to steroid measurement by radioimmunoassay (RIA) or enzyme immunoassay (EIA). Steroid extraction is critical because it can remove substances that interfere with the RIA or EIA. Steroid extraction is commonly achieved using organic solvents, such as diethyl ether or dichloromethane. However, organic solvent extractions can suffer from low recovery, imprecise recovery, or incomplete removal of assay interference. Here, we describe validations of a simple protocol to extract steroids (e.g., dehydroepiandrosterone, corticosterone, and estradiol) from avian plasma, serum, and brain tissue using solid phase extraction (SPE) with commercially available C18 columns. We compare various methods for (1) eluting steroids from columns, (2) drying eluates, and (3) resuspending dried eluates prior to RIA. The SPE method yields high and consistent recoveries. The SPE method also effectively separates steroids from interfering substances, even when extracting steroids from lipid-rich plasma and brain tissue. These data indicate that SPE is superior to organic solvent extraction on several measures. SPE should be broadly useful for extracting steroids from plasma or tissue samples.

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.

3beta-HSD activates DHEA in the songbird brain

Dehydroepiandrosterone (DHEA) is an abundant circulating prohormone in humans, with a variety of reported actions on central and peripheral tissues. Despite its abundance, the functions of DHEA are relatively unknown because common animal models (laboratory rats and mice) have very low DHEA levels in the blood. Over the past decade, we have obtained considerable evidence from avian studies demonstrating that (1) DHEA is an important circulating prohormone in songbirds and (2) the enzyme 3beta-hydroxysteroid dehydrogenase/isomerase (3beta-HSD), responsible for converting DHEA into a more active androgen, is expressed at high levels in the songbird brain. Here, we first review biochemical and molecular studies demonstrating the widespread activity and expression of 3beta-HSD in the adult and developing songbird brain. Studies examining neural 3beta-HSD activity show effects of sex, stress, and season that are region-specific. Second, we review studies showing seasonal and stress-related changes in circulating DHEA in captive and wild songbird species. Third, we describe evidence that DHEA treatment can stimulate song behavior and the growth of neural circuits controlling song behavior. Importantly, brain 3beta-HSD and aromatase can work in concert to locally metabolize DHEA into active androgens and estrogens, which are critical for controlling behavior and robust adult neuroplasticity in songbirds. DHEA is likely secreted by the avian gonads and/or adrenals, as is the case in humans, but DHEA may also be synthesized de novo in the songbird brain from cholesterol or other precursors. Irrespective of its source, DHEA seems to be an important prohormone in songbirds, and 3beta-HSD is a key enzyme in the songbird brain.

Analysis of clinical symptomatology, extrapyramidal symptoms and neurocognitive dysfunction following dehydroepiandrosterone (DHEA) administration in olanzapine treated schizophrenia patients: a randomized, double-blind placebo controlled trial

Several studies have demonstrated the effective use of dehydroepiandrosterone (DHEA) in the management of mood, however studies of its use in psychosis remain limited. The aim of this study was to investigate for the first time efficacy of DHEA augmentation with standardized antipsychotic medication (olanzapine) and to explore effects of DHEA augmentation on side-effect profiles including weight gain, glucose tolerance, aggression, quality of life and neurocognitive function. Finally, we aimed to analyze any relationship between plasma levels and clinical response to DHEA administration. Forty patients with chronic schizophrenia stabilized on olanzapine were randomized in double-blind fashion to receive either DHEA (titrated up to 150mg) or placebo augmentation for a period of 12-weeks. Blood samples were collected at baseline, mid-study and study completion. Results indicated improvement of negative symptoms (SANS scale) even when baseline scores were controlled as a covariate. Some improvement in Parkinsonism and akathisia compared to baseline was seen in patients receiving DHEA. No change in psychosis as reflected by the PANSS was noted. Patients receiving DHEA appeared to demonstrate relatively stable glucose levels compared to controls at the end of the study. An improvement in cognitive performance (most notably memory), which did not reach significance due to low sample number, was observed following DHEA administration. Results further suggest preliminary evidence of involvement of the neurosteroid system in schizophrenia pathophysiology, and confirm initial "cautious" findings identifying an agent capable of improving negative symptoms and certain features of extrapyramidal side effects.

Effects of DHEA administration on episodic memory, cortisol and mood in healthy young men: a double-blind, placebo-controlled study

RATIONALE

Dehydroepiandrosterone (DHEA) has been reported to enhance cognition in rodents, although there are inconsistent findings in humans.

OBJECTIVES

The aim of this study was to investigate the effects of DHEA administration in healthy young men on episodic memory and its neural correlates utilising an event-related potential (ERP) technique.

METHODS

Twenty-four healthy young men were treated with a 7-day course of oral DHEA (150 mg b.d.) or placebo in a double blind, random, crossover and balanced order design. Subjective mood and memory were measured using visual analogue scales (VASs). Cortisol concentrations were measured in saliva samples. ERPs were recorded during retrieval in an episodic memory test. Low-resolution brain electromagnetic tomography (LORETA) was used to identify brain regions involved in the cognitive task.

RESULTS

DHEA administration led to a reduction in evening cortisol concentrations and improved VAS mood and memory. Recollection accuracy in the episodic memory test was significantly improved following DHEA administration. LORETA revealed significant hippocampal activation associated with successful episodic memory retrieval following placebo. DHEA modified ERPs associated with retrieval and led to a trend towards an early differential activation of the anterior cingulate cortex (ACC).

CONCLUSIONS

DHEA treatment improved memory recollection and mood and decreased trough cortisol levels. The effect of DHEA appears to be via neuronal recruitment of the steroid sensitive ACC that may be involved in pre-hippocampal memory processing. These findings are distinctive, being the first to show such beneficial effects of DHEA on memory in healthy young men.

Testosterone and aggression: Berthold, birds and beyond

Berthold's classic study of domesticated roosters in 1849 demonstrated that testicular secretions are necessary for the normal expression of aggressive behaviour. Although this conclusion is undoubtedly correct, field studies of wild songbirds have yielded important modifications and limitations of Berthold's original hypothesis. For example, studies of the North American song sparrow (Melospiza melodia) during the breeding season reveal that not only does testosterone increase aggression, but aggressive interactions also increase plasma testosterone levels. Furthermore, in winter, nonbreeding song sparrows have low plasma testosterone levels but are very aggressive, and castration of nonbreeding song sparrows does not decrease aggression. Interestingly, an aromatase inhibitor (fadrozole) does decrease male aggression in the nonbreeding season, and the effects of fadrozole can be rescued with oestradiol. In winter, dehydroepiandrosterone (DHEA) from the periphery can be metabolised within the brain to supply oestradiol to specific neural circuits. Additionally, oestradiol might be synthesised de novo from cholesterol entirely within the brain. These mechanisms may have evolved to avoid the 'costs' of circulating testosterone in the nonbreeding season. Recent studies in tropical birds, hamsters, and humans suggest that these neuroendocrine mechanisms are important for the control of aggression in many vertebrate species.

The relevance of neurosteroids to clinical psychiatry: from the laboratory to the bedside

Neurosteroids are important neuroactive molecules with suggested central involvement in several neurophysiological and psychiatric disease processes. The discovery of neurosteroids followed the revelation that the brain exhibited the capacity to synthesize its own steroids in situ and thus be a potential site of steroidogenesis. In contrast to some steroids that exhibit traditional genomic steroid actions, most neurosteroids appear to regulate neuronal function by means of "non-genomic" mechanisms influencing neuronal excitability. Neurosteroids are synthesized either from CNS cholesterol or from peripheral steroid precursors and exhibit a wide range of modulatory effects on neurotransmitter receptor activity, most notably at the gamma-aminobutyric acid A (GABA(A)) receptor. Neurosteroids play an important role in neurodevelopment and neuroprotective effects, many aspects of which may have particular applicability to psychiatric disorders including various gender differences. Neurosteroids appear to be relevant to the pathophysiology and pharmacological treatment of many psychiatric disorders including the most notable mood and anxiety disorders, but also psychotic, childhood, eating, dementia, stress and postpartum disorders. It has been suggested that neurosteroids may become potential targets for pharmacological intervention in the future with further neurosteroid investigation contributing to a more comprehensive understanding of human behavior and psychopathology.

Sulfonation in pharmacology and toxicology

Sulfonation has a major function in modulating the biological activities of a wide number of endogenous and foreign chemicals, including: drugs, toxic chemicals, hormones, and neurotransmitters. The activation as well as inactivation of many xenobiotics and endogenous compounds occurs via sulfonation. The process is catalyzed by members of the cytosolic sulfotransferase (SULT) superfamily consisting of at least ten functional genes in humans. The reaction in intact cells may be reversed by arylsulafatase present in the endoplasmic reticulum. Under physiological conditions, sulfonation is regulated, in part, by the supply of the co-substrate/donor molecule 3'-phosphadensoine-5-phosphosulfate (PAPS), and transport mechanisms by which sulfonated conjugates enter and leave cells. Variation in the response of individuals to certain drugs and toxic chemicals may be related to genetic polymorphisms documented to occur in each of the above pathways. Sulfonation has a major function in regulating the endocrine status of an individual by modulating the receptor activity of estrogens and androgens, steroid biosynthesis, and the metabolism of catecholamines and iodothyronines Sulfonation is a key reaction in the body's defense against injurious chemicals and may have a major function during early development since SULTs are highly expressed in the human fetus. As with many Phase I and Phase II reactions, sulfonation may also serve as the terminal step in activating certain dietary and environmental agents to very reactive toxic intermediates implicated in carcinogenesis.

Sex differences in pregnenolone sulphate in the chick brain after training

Pregnenolone and pregnenolone sulphate are potent memory enhancers when administered to rodents prior to various learning and memory paradigms. Here, we show that training on a passive avoidance task results in the increased concentration of pregnenolone sulphate in the medial striatum, formerly known as lobus parolfactorius of female but not male chicks. In addition, we demonstrated potential for neuronal synthesis of pregnenolone in the day-old chick brain, including in the intermediate medial mesopallium, formerly known as intermediate medial hyperstriatum ventrale and the medial striatum.

Elevation of the cortisol/dehydroepiandrosterone ratio in schizophrenia patients

Dehydroepiandrosterone (DHEA) and its sulfate derivative DHEA-S are neurosteroids, produced in the brain, and neuroactive steroids, produced in the adrenals and affecting the brain. We compared the ratios of serum cortisol/DHEA or DHEA-S in schizophrenia patients with normal subjects, and determined the correlation of these ratios with psychopathology and distress. Early morning plasma concentrations of DHEA, DHEA-S, and cortisol were determined by radioimmunassay in 40 medicated schizophrenia inpatients, and 15 healthy subjects with similar age and sex distribution. Subjects were assessed for psychopathology using the Positive and Negative Syndrome Scale (PANSS) and the Montgomery and Asberg Depression Rating Scale (MADRS), anxiety, anger, emotional and somatic distress levels. Schizophrenia inpatients demonstrated significantly higher levels of state and trait anxiety, anger expression index, emotional and somatic self-reported distress scores. Cortisol/DHEA and cortisol/DHEA-S ratios were significantly higher in schizophrenia patients than in healthy comparison subjects. Both ratios correlated positively with age and duration of illness; cortisol/DHEA-S ratio also showed positive association with age of illness onset. When age, illness duration and age of onset were controlled, cortisol/DHEA-S ratio significantly correlated with severity of depression (MADRS, r=0.33, p=0.048), state and trait anxiety (r=0.43, p=0.008 and r=0.40, p=0.014, respectively), trait anger (r=0.41, p=0.012), angry temperament (r=0.46, p=0.004), anger expression index (r=0.36, p=0.033), and hostility (r=0.42, p=0.010). No significant association was found between these ratios and severity of psychopathology, and type or dosage of antipsychotic agents. Thus, elevated cortisol/DHEA and/or cortisol/DHEA-S ratios in schizophrenia patients are positively associated with higher scores for anxiety and anger, depression and hostility, age and age of onset/duration of illness, but are independent of severity of psychopathology (PANSS) and antipsychotic treatment.

Low and high circulating cortisol levels predict mortality and cognitive dysfunction early after stroke

OBJECTIVE

Elevated cortisol levels are associated with confusion and poor outcome after stroke. Dehydroepiandrosterone sulphate (DS), the most abundant adrenal androgen may act as an anti-glucocorticoid. An altered regulation of these steroids may affect numerous brain functions, including neuronal survival. The purpose of this study was to investigate serum cortisol and DS levels and the cortisol/DS ratio early after stroke and relate our findings to the presence of disorientation and mortality.

DESIGN

Patients with acute ischaemic stroke (n = 88, 56 men and 32 women) admitted to a stroke unit were investigated with repeated clinical assessments and scores for degree of confusion, extent of paresis and level of functioning. Serum cortisol (C) and DS were measured on day 1 and/or day 4. Data for 28-day and 1-year mortality are presented. A control group of 65 age-matched healthy individuals was used. Multivariate analyses of mortality rates in the different tertiles or sixtiles of serum cortisol were performed with logistic regression, adjusting for age, sex, diabetes and level of consciousness.

RESULTS

There was no difference in serum cortisol levels on day 1 for stroke patients when compared with control group values. Initial cortisol levels were significantly higher in the patients with acute disorientation versus orientated patients (P < 0.05). Cortisol levels on day 1 were an independent predictor of 28-day mortality, and patients with low cortisol levels (<270 nmol L(-1)) and increased levels (>550 nmol L(-1)) both had an increased 1-year mortality. DS levels on day 1 were significantly elevated in stroke patients.

CONCLUSION

Hypercortisolism is associated with cognitive dysfunction early after ischaemic stroke. High and low circulating cortisol levels are associated with increased mortality after stroke. DS levels were not associated with clinical outcome.

The delayed administration of dehydroepiandrosterone sulfate improves recovery of function after traumatic brain injury in rats

The goal of the current study was to test the hypothesis that dehydroepiandrosterone-sulfate (DHEAS), a pro-excitatory neurosteroid, could facilitate recovery of function in male rats after delayed treatment following TBI. DHEAS has been found to play a major role in brain development and aging by influencing the migration of neurons, arborization of dendrites, and formation of new synapses. These characteristics make it suitable as a potential treatment to enhance neural repair in response to CNS injury. In our study, behavioral tests were conducted concurrently with DHEAS administration (0, 5, 10, or 20 mg/kg) starting seven days post-injury (PI). These assays included 10 days of Morris Water Maze testing (MWM; 7d PI), 10 days of Greek-Cross (GC; 21d PI), Tactile Adhesive Removal task (TAR; PI days: 6, 13, 20, 27, 34), and spontaneous motor behavior testing (SMB; PI days: 2, 4, 6, 12, 19, 26, 33). Brain-injured rats showed an improvement in performance in all tasks after 5, 10, or 20 mg/kg DHEAS. The most effective dose of DHEAS in the MWM was 10 mg/kg, while in the GC it was 20 mg/kg, in TAR 5 mg/kg, and all doses, except for vehicle, were effective at reducing injury-induced SMB hyperactivity. In no task did DHEAS-treated animals perform worse than the injured controls. In addition, DHEAS had no significant effects on behavioral performance in the sham-operates. These results can be interpreted to demonstrate that after a 7-day delay, the chronic administration of DHEAS to injured rats significantly improves behavioral recovery on both sensorimotor and cognitive tasks.