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Publication
Journal: International Journal of Cancer
May/21/2006
Abstract
In a large case-control study on breast cancer risk and serum hormone concentrations, nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort, we examined to what extent the relationship of excess body weight with breast cancer risk may be explained by changes in sex steroids. Height, weight, waist and hip circumferences, and serum measurements of testosterone [T], androstenedione [Delta4], dehydroepiandrosterone sulphate [DHEAS], estradiol [E2], estrone [E1] and sex-hormone binding globulin [SHBG] were available for 613 breast cancer cases, and 1,139 matched controls, who were all menopausal at the time of blood donation. Free T [fT] and free E2 [fE2] were calculated using mass action equations. Breast cancer risk was related to body mass index (BMI) (RR = 1.11 [0.99-1.25], per 5 kg/m2 increase in BMI), and waist (RR = 1.12 [1.02-1.24], per 10 cm increase) and hip circumferences (RR = 1.14 [1.02-1.27], per 10 cm increase). The increase in breast cancer risk associated with adiposity was substantially reduced after adjustment for any estrogens, especially for fE2 (from 1.11 [0.99-1.25] to 0.99 [0.87-1.12], from 1.12 [1.02-1.24] to 1.02 [0.92-1.14] and from 1.14 [1.02-1.27] to 1.05 [0.93-1.18] for BMI, waist and hip circumferences, respectively). A modest attenuation in excess risk was observed after adjustment for fT, but the remaining androgens had little effect on the association of body adiposity with breast cancer. Our data indicate that the relationship of adiposity with breast cancer in postmenopausal women could be partially explained by the increases in endogenous estrogens, and by a decrease in levels of SHBG.
Publication
Journal: Journal of Applied Physiology
September/13/2004
Abstract
The purpose of this study was to determine the acute anabolic and catabolic hormone response to endurance and resistance exercise bouts of equal volume in subjects with differing training status. Twenty-two healthy men were recruited who were either resistance trained (n = 7), endurance trained (n = 8), or sedentary (n = 7). Three sessions were completed: a resting session, a 40-min run at 50-55% maximal oxygen consumption, and a resistance exercise session. Expired gases were monitored continuously during exercise, and the endurance and resistance exercise sessions were individually matched for caloric expenditure. Blood samples were drawn before exercise and 1, 2, 3, and 4 h after the start of the exercise. Plasma was analyzed for luteinizing hormone, dehydroepiandrosterone sulfate, cortisol, and free and total testosterone. Androgens increased in response to exercise, particularly resistance exercise, whereas cortisol only increased after resistance exercise. Dehydroepiandrosterone sulfate levels increased during the resistance exercise session and remained elevated during recovery in the resistance-trained subjects. Endurance-trained subjects displayed less pronounced changes in hormone concentrations in response to exercise than resistance-trained subjects. After an initial postexercise increase, there was a significant decline in free and total testosterone during recovery from resistance exercise (P < 0.05), particularly in resistance-trained subjects. On the basis of the results of this study, it appears that the endogenous hormone profile of men is more dependent on exercise mode or intensity than exercise volume as measured by caloric expenditure. The relatively catabolic environment observed during the resistance session may indicate an intensity-rather than a mode-dependent response.
Publication
Journal: Brain research. Brain research reviews
February/10/2002
Abstract
Steroids, synthesized in peripheral glands or centrally in the brain--the latter being named neurosteroids--exert an important role as modulators of the neuronal activity by interacting with different receptors or ion channels. In addition to the modulation of GABA(A), NMDA or cholinergic receptors, neuroactive steroids interact with an atypical intracellular receptor, the sigma(1) protein. This receptor has been cloned in several species, and highly selective synthetic ligands are available. At the cellular level, sigma1 agonists modulate intracellular calcium mobilization and extracellular calcium influx, NMDA-mediated responses, acetylcholine release, and alter monoaminergic systems. At the behavioral level, the sigma1 receptor is involved in learning and memory processes, the response to stress, depression, neuroprotection and pharmacodependence. Pregnenolone, dehydroepiandrosterone, and their sulfate esters behave as sigma1 agonists, while progesterone is a potent antagonist. This review will detail the physiopathological consequences of these interactions, focusing on recent results on memory and depression. The therapeutical interest of selective sigma1 receptor agonists in alleviating aging-related cognitive deficits will be discussed.
Publication
Journal: American Journal of Epidemiology
January/16/2003
Abstract
The aging process is characterized by a number of gradual changes in circulating hormone concentrations as well as a gradual increase in the degree of atherosclerosis. The authors studied whether serum hormone levels are related to atherosclerosis of the carotid artery in independently living, elderly men. In 1996, 403 men (aged 73-94 years) were randomly selected from the general population of Zoetermeer, the Netherlands. Carotid artery intima-media thickness was determined. Serum concentrations of testosterone; estrone; estradiol; dehydroepiandrosterone and dehydroepiandrosterone sulfate; insulin-like growth factor I (IGF-I) (total and free) and its binding proteins IGFBP-1, IGFBP-2, and IGFBP-3; and leptin were measured. After the authors adjusted for age, serum testosterone, estrone, and free IGF-I were inversely related to intima-media thickness. The strength of these relations was as powerful in subjects with as in those without prevalent cardiovascular disease. Serum estradiol; dehydroepiandrosterone sulfate; total IGF-I, IGFBP-1, IGFBP-2, and IGFBP-3; and leptin showed no association. These findings suggest that endogenous testosterone, estrone, and free IGF-I levels may play a protective role in the development of atherosclerosis in aging men.
Publication
Journal: Neuropsychopharmacology
November/6/2005
Abstract
The acute effects of smoking a low- or high-nicotine cigarette on hypothalamic-pituitary-adrenal (HPA) hormones, subjective responses, and cardiovascular measures were studied in 20 healthy men who met American Psychiatric Association Diagnostic and Statistical Manual IV criteria for nicotine dependence. Within four puffs (or 2 min) after cigarette smoking began, plasma nicotine levels and heart rate increased significantly (P<0.01), and peak ratings of 'high' and 'rush' on a Visual Analogue Scale were reported. Reports of 'high', 'rush', and 'liking' and reduction of 'craving' were significantly greater after smoking a high-nicotine cigarette than a low-nicotine cigarette (P<0.05). Peak plasma nicotine levels after high-nicotine cigarette smoking (23.9+/-2.6 ng/ml) were significantly greater than after low-nicotine cigarette smoking (3.63+/-0.59 ng/ml) (P<0.001). After smoking a low-nicotine cigarette, adrenocorticotropin hormone (ACTH), cortisol, dehydroepiandrosterone (DHEA), and epinephrine did not change significantly from baseline. After high-nicotine cigarette smoking began, plasma ACTH levels increased significantly above baseline within 12 min and reached peak levels of 21.88+/-5.34 pmol/l within 20 min. ACTH increases were significantly correlated with increases in plasma nicotine (r=0.85; P<0.0001), DHEA (r=0.66; P=0.002), and epinephrine (r=0.86; P<0.0001). Cortisol and DHEA increased significantly within 20 min (P<0.05) and reached peak levels of 424+/-48 and 21.13+/-2.55 ng/ml within 60 and 30 min, respectively. Thus cigarette smoking produced nicotine dose-related effects on HPA hormones and subjective and cardiovascular measures. These data suggest that activation of the HPA axis may contribute to the abuse-related effects of cigarette smoking.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
June/6/2006
Abstract
BACKGROUND
Adolescent hyperandrogenemia is considered a forerunner of adult polycystic ovary syndrome, but its etiology remains uncertain.
OBJECTIVE
Our objective was to explore the hypothesis that peripubertal obesity is associated with hyperandrogenemia.
METHODS
We performed a cross-sectional analysis of data obtained at General Clinical Research Centers.
METHODS
Subjects were 41 obese [body mass index (BMI) for age,>>or=95%] and 35 normal-weight (BMI for age, <95%) peripubertal girls.
METHODS
We used pooled blood samples (approximately 0500-0700 h; n = 64) while fasting or single morning (fasting) samples (n = 12).
METHODS
We assessed adiposity and androgen concentrations.
RESULTS
BMI correlated with total testosterone (T) (r(s) = 0.59), SHBG (r(s) = -0.69), and free T (r(s) = 0.69); free T was three times as great in obese girls compared with normal-weight girls (P < 0.0001 for all). BMI correlated with insulin (r(s) = 0.52); both insulin and LH correlated with free T (r(s) = 0.45 and 0.44, respectively; P < 0.001 for all). When analyzing early pubertal girls (pubertal stages 1-3; n = 36) alone, BMI correlated with total T (r(s) = 0.65), SHBG (r(s) = -0.74), and free T (r(s) = 0.75); free T was five times as great in obese early-pubertal girls (P < 0.001 for all). BMI correlated with insulin (r(s) = 0.65), and insulin correlated with free T (r(s) = 0.63, P < 0.01 for both). BMI correlated with free T while simultaneously adjusting for age, pubertal stage, insulin, LH, and dehydroepiandrosterone sulfate.
CONCLUSIONS
Peripubertal obesity is associated with marked hyperandrogenemia, which is especially pronounced in early puberty.
Publication
Journal: American Journal of Respiratory and Critical Care Medicine
June/15/2011
Abstract
BACKGROUND
Sex hormones have effects on the left ventricle, but hormonal influences on the right ventricle (RV) are unknown.
OBJECTIVE
We hypothesized that sex hormones would be associated with RV morphology in a large cohort free of cardiovascular disease.
METHODS
Sex hormones were measured by immunoassay and RV ejection fraction (RVEF), stroke volume (RVSV), mass, end-diastolic volume, and end-systolic volume (RVESV) were measured by cardiac magnetic resonance imaging in 1,957 men and 1,738 postmenopausal women. The relationship between each hormone and RV parameter was assessed by multivariate linear regression.
RESULTS
Higher estradiol levels were associated with higher RVEF (β per 1 ln[nmol/L], 0.88; 95% confidence interval [CI], 0.32 to 1.43; P = 0.002) and lower RVESV (β per 1 ln[nmol/L], -0.87; 95% CI, -1.67 to -0.08; P = 0.03) in women using hormone therapy. In men, higher bioavailable testosterone levels were associated with higher RVSV (β per 1 ln[nmol/L], 1.97; 95% CI, 0.20 to 3.73; P = 0.03) and greater RV mass and volumes (P ≤ 0.01). Higher dehydroepiandrosterone levels were associated with higher RVSV (β per 1 ln[nmol/L], 1.37; 95% CI, 0.15 to 2.59; P = 0.03) and greater RV mass (β per 1 ln[nmol/L], 0.25; 95% CI, 0.00 to 0.49; P = 0.05) and volumes (P ≤ 0.001) in women.
CONCLUSIONS
Higher estradiol levels were associated with better RV systolic function in women using hormone therapy. Higher levels of androgens were associated with greater RV mass and volumes in both sexes.
Publication
Journal: Journal of Biological Chemistry
February/20/1990
Abstract
Progesterone and 17 alpha-hydroxyprogesterone (but not other steroids such as testosterone, corticosterone, beta-estradiol, estrone, dehydroepiandrosterone, 20 alpha-hydroxypregnen-3-one, androstenedione, and pregnenolone) were shown to cause an immediate increase, in free cytosolic calcium ([Ca2+]i) in both capacitated and noncapacitated human sperm, using the fluorescent indicator fura 2. Significant increases in [Ca2+]i were observed with 10 ng/ml progesterone, while maximum effects were seen with 1 microgram/ml progesterone. Two other steroids 11 beta-hydroxyprogesterone and 5 alpha-pregnane-3,20-dione exhibited significant activity to increase [Ca2+]i. This increase in [Ca2+]i elicited by progesterone was entirely due to Ca2+ influx from the extracellular medium since the increase in [Ca2+]i was blocked by the Ca2+ chelator EGTA (2.5 mM) and the Ca2+ channel antagonist La3+ (0.25 mM) when added to the medium containing 2.5 mM Ca2+. Progesterone also stimulated the uptake of Mn2+ into sperm as measured by the quenching of fura 2 fluorescence. Progesterone has been found in human follicular fluid at levels capable of stimulating increases in [Ca2+]i. The similarities in responses induced by human follicular fluid and progesterone an increase in [Ca2+]i, and hence the acrosome reaction, is progesterone and/or 17 alpha-hydroxyprogesterone. Progesterone (1 microgram/ml) did not increase [Ca2+]i in somatic cells such as adipocytes, hepatocytes, Balb/c 3T3 cells, normal rat kidney, or DDT1 MF-2 cells. The effects of these progestins to increase [Ca2+]i, by activating a receptor-operated calcium channel, is the first report of such an activity in sperm. This phenomena possibly opens up a new field of steroid action in the area of sterility, fertility, and contraception at the level of the sperm.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
July/1/1998
Abstract
Interleukin-6 (IL-6) is one of the pathogenetic elements in inflammatory and age-related diseases such as rheumatoid arthritis, osteoporosis, atherosclerosis, and late-onset B cell neoplasia. In these diseases or during aging, the decrease in production of sex hormones such as dehydroepiandrosterone (DHEA) is thought to play an important role in IL-6-mediated pathogenetic effects in mice. In humans, we investigated the correlation of serum levels of DHEA, DHEA sulfate (DHEAS), or androstenedione (ASD) and IL-6, tumor necrosis factor-alpha, or IL-2 with age in 120 female and male healthy subjects (15-75 yr of age). Serum DHEA, DHEAS, and ASD levels significantly decreased with age (all P < 0.001), whereas serum IL-6 levels significantly increased with age (P < 0.001). DHEA/DHEAS and IL-6 (but not tumor necrosis factor-alpha or IL-2) were inversely correlated (all patients: r = -0.242/-0.312; P = 0.010/0.001). In female and male subjects, DHEA and ASD concentration dependently inhibited IL-6 production from peripheral blood mononuclear cells (P = 0.001). The concentration-response curve for DHEA was U shaped (maximal effective concentration, 1-5 x 10(-8) mol/L), which may be the optimal range for immunomodulation. In summary, the data indicate a functional link between DHEA or ASD and IL-6. It is concluded that the increase in IL-6 production during the process of aging might be due to diminished DHEA and ASD secretion. Immunosenescence may be directly related to endocrinosenescence, which, in turn, may be a significant cofactor for the manifestation of inflammatory and age-related diseases.
Publication
Journal: Obesity research
September/27/1999
Abstract
OBJECTIVE
Both obesity and insulin resistance increase the risk of hypertension and other cardiovascular diseases, but the mechanisms linking these abnormalities are unknown. The current study was undertaken to examine the effects of obesity, fat distribution, and insulin resistance on plasma levels of aldosterone and other adrenal steroids that might contribute to sequelae of obesity.
METHODS
Twenty-eight normotensive premenopausal women and 27 normotensive men with a wide range of body fat underwent measurements of visceral adipose tissue by CT scan, total fat mass by dual energy X-ray absorptiometry, blood pressure, insulin sensitivity, and plasma levels of three adrenal steroid hormones.
RESULTS
Plasma aldosterone in women correlated directly with visceral adipose tissue (r=0.66, p<0.001) and inversely with insulin sensitivity (r=-0.67, p<0.001), and these associations were independent of plasma renin activity. There were no corresponding correlations in men. Plasma aldosterone was significantly correlated with plasma cortisol and dehydroepiandrosterone sulfate in women. Seventeen women and 15 men completed a weight-reduction regimen, losing an average of 15.1+1.2 kg. After weight loss, plasma aldosterone was significantly lower and insulin sensitivity higher; however, the correlations of aldosterone with visceral adipose tissue and insulin sensitivity in women persisted (p = 0.09 and 0.07, respectively). Although none of the women were hypertensive, blood pressure correlated with plasma aldosterone both before and after weight loss.
CONCLUSIONS
We conclude that visceral adiposity and insulin resistance are associated with increased plasma aldosterone and other adrenal steroids that may contribute to cardiovascular diseases in obese women.
Publication
Journal: Journal of Science and Medicine in Sport
January/4/2012
Abstract
OBJECTIVE
This paper discusses the use of saliva analysis as a tool for monitoring steroid, peptide, and immune markers of sports training.
METHODS
Salivary gland physiology, regarding the regulation and stimulation of saliva secretion, as well as methodological issues including saliva collection, storage and analysis are addressed in this paper. The effects of exercise on saliva composition are then considered.
METHODS
Exercise elicits changes in salivary levels of steroid hormones, immunoglobulins, antimicrobial proteins and enzymes. Cortisol, testosterone and dehydroepiandrosterone can be assessed in saliva, providing a non-invasive option to assess the catabolic and anabolic effects of exercise. Validation studies using blood and salivary measures of steroid hormones are addressed in this paper. Effects of acute exercise and training on salivary immunoglobulins (SIgA, SIgM, SIgG) and salivary antimicrobial proteins, including α-amylase, lysozyme and lactoferrin, are also discussed.
RESULTS
Analysis of cortisol and testosterone in saliva may help detect the onset of non-functional overreaching and subsequently may help to prevent the development of overtraining syndrome. Assessment of salivary immunoglobulins and antimicrobial proteins has been shown to successfully represent the effects of exercise on mucosal immunity. Increases in SIgA and antimicrobial proteins concentration and/or secretion rate are associated with acute exercise whereas conversely, decreases have been reported in athletes over a training season leaving the athlete susceptible for upper respiratory tract infections.
CONCLUSIONS
The measurement of physiological biomarkers in whole saliva can provide a significant tool for assessing the immunological and endocrinological status associated with exercise and training.
Publication
Journal: Journal of the American Geriatrics Society
June/24/1999
Abstract
OBJECTIVE
The purpose of this study was to determine whether endogenous steroid hormone levels are associated with depressed mood in community-dwelling older women.
METHODS
A cross-sectional population-based study.
METHODS
Rancho Bernardo, California
METHODS
A total of 699 non-estrogen using, community-dwelling, postmenopausal women (aged 50 to 90 years) from the Rancho Bernardo cohort who were screened for depressed mood and had plasma obtained for steroid hormone assays in 1984-1987.
METHODS
Plasma levels of total and bioavailable (non-SHBG-bound) estradiol and testosterone, estrone, androstenedione, cortisol, dehydroepiandrosterone, and (DHEA) and its sulfate (DHEAS) were measured by radioimmunoassay. Mood and depression were assessed using the Beck Depression Inventory.
RESULTS
Only DHEAS levels were significantly and inversely associated with depressed mood, and the association was independent of age, physical activity, and weight change (P = .0002). Age, sedentary lifestyle, and weight loss were positively associated with depressed mood. Alcohol intake, cigarette smoking, marital status, type of menopause, and season of testing were unassociated with depressed mood. A subset of 31 women with categorically defined depression had lower DHEAS levels compared with 93 age-matched nondepressed women (1.17 +/- 1.08 vs 1.57 +/- .98 micromol/L; P = .01).
CONCLUSIONS
These results add to the evidence that DHEA/S is a neuroactive steroid and point to the need for careful long-term clinical trials of DHEA therapy in older women with depressed mood.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
May/27/2003
Abstract
Polycystic ovary syndrome (PCOS) is associated with hyperinsulinemia, insulin resistance (IR), increased risk of glucose intolerance, and type 2 diabetes. Family studies have indicated a genetic susceptibility to PCOS. The aims of this study were 1) to assess glucose tolerance status, gonadotropins, and androgens in first degree relatives of patients with PCOS; and 2) to assess IR in normal glucose tolerant (NGT) family members. One hundred two family members of 52 patients with PCOS [Mothers(PCOS) (n = 34; mean age, 46.5 yr; mean body mass index (BMI), 28.8 kg/m(2)), Fathers(PCOS) (n = 24; mean age, 50.4 yr; mean BMI, 27.5 kg/m(2)), Sisters(PCOS) (n = 19; mean age, 25.1 yr; mean BMI, 22.9 kg/m(2)), and Brothers(PCOS) (n = 25; mean age, 23.7 yr; mean BMI, 22.5 kg/m(2))] and 82 unrelated healthy control subjects without a family history of diabetes or PCOS (4 age- and weight-matched subgroups, i.e. Control(MothersPCOS), Control(FathersPCOS), Control(SistersPCOS), and Control(BrothersPCOS)) were studied. Glucose and insulin (at baseline and during a 75-g, 2-h oral glucose tolerance test) were measured. IR was assessed by fasting insulin (FI), fasting glucose to insulin ratio (FGI), homeostatic model assessment (HOMA IR), and area under the curve for insulin during the oral glucose tolerance test (AUC(insulin)) in NGT Mothers(PCOS), Fathers(PCOS), Sisters(PCOS), Brothers(PCOS), and matched control subgroups. Including the prestudy-diagnosed 3 mothers and 2 fathers with diabetes, diabetes and impaired glucose tolerance (IGT) were noted in 16% and 30% of Mothers(PCOS) and 27% and 31% of Fathers(PCOS), respectively. There was no diabetes in Sisters(PCOS) and Brothers(PCOS). IGT was found in 5% of Sisters(PCOS). Impaired fasting glucose was found in 3% of Mothers(PCOS) and 4% of Brothers(PCOS). The analysis of NGT family members showed that Mothers(PCOS) had higher FI (P < 0.05), HOMA IR (P < 0.05), and AUC(insulin) (P < 0.01) and lower FGI (P < 0.05) than Control(MothersPCOS), whereas all IR parameters were comparable between Fathers(PCOS) and their matched control subgroup. Sisters(PCOS) had higher FI (P < 0.05), HOMA IR (P < 0.01), and AUC(insulin) (P < 0.05) and lower FGI (P < 0.01), and Brothers(PCOS) had higher AUC(insulin) (P < 0.01) than their matched control subgroups, respectively. Mothers(PCOS) had higher testosterone levels than Control(MothersPCOS) (P < 0.01 and P < 0.05 for pre- and postmenopausal women, respectively). Sisters(PCOS) had higher LH (P < 0.01), testosterone (P < 0.001), androstenedione (P < 0.01), and dehydroepiandrosterone sulfate (P < 0.05) levels than Control(SistersPCOS). There was no difference in gonadotropin and androgen levels in Fathers(PCOS) compared with Control(FathersPCOS) or in Brothers(PCOS) compared with Control(BrothersPCOS). Our results suggest that 1) first degree relatives of patients with PCOS may be at high risk for diabetes and glucose intolerance; 2) NGT female family members have insulin resistance; and 3) mothers and sisters of PCOS patients have higher androgen levels than control subjects. We propose that the high risks of these impairments warrant screening in first degree relatives of patients with PCOS.
Publication
Journal: Human Genetics
September/22/1980
Abstract
Steroid sulfatase (STS) activities in female fibroblast strains are significantly higher than in male strains, as determined by cleavage of dehydroepiandrosterone sulfate. The difference is probably not due to hormonal control of gene expression, but suggests that for this X-linked locus there is no gene dosage compensation.
Publication
Journal: Journal of Sexual Medicine
February/27/2012
Abstract
BACKGROUND
The circulation of large amounts of dehydroepiandrosterone (DHEA) and its sulfated derivative (DHEA-S) suggests a physiological role in human physiology. In the central nervous system, DHEA is considered a neurosteroid with a wide range of functions.
OBJECTIVE
The goal of this review is to discuss metabolism, biochemical, and physiological mechanism of DHEA action and the potential role of DHEA in aging and in ameliorating a host of pathological conditions, associated with aging.
METHODS
We examined preclinical and clinical data reported in various studies from the available literature concerning the effects of DHEA in normal and pathological conditions.
METHODS
Data reported in the literature were analyzed, reviewed, and discussed.
RESULTS
DHEA mediates its action via multiple signaling pathways involving specific membrane receptors and via transformation into androgen and estrogen derivatives (e.g., androgens, estrogens, 7α and 7β DHEA, and 7α and 7β epiandrosterone derivatives) acting through their specific receptors. These pathways include: nitric oxide synthase activation, modulation of γ-amino butyric acid receptors, N-methyl D-aspartate, receptors sigma receptors (Sigma-1), differential expression of inflammatory factors, adhesion molecules and reactive oxygen species, among others. Clinical and epidemiological studies suggested that low DHEA levels might be associated with ischemic heart disease, endothelial dysfunction, atherosclerosis, bone loss, inflammatory diseases, and sexual dysfunction. Most importantly, no significant adverse or negative side effects of DHEA were reported in clinical studies of men and women.
CONCLUSIONS
DHEA modulates endothelial function, reduces inflammation, improves insulin sensitivity, blood flow, cellular immunity, body composition, bone metabolism, sexual function, and physical strength in frailty and provides neuroprotection, improves cognitive function, and memory enhancement. DHEA possesses pleiotropic effects and reduced levels of DHEA and DHEA-S may be associated with a host of pathologies; however, the clinical efficacy of DHEA supplementation in ameliorating patho-physiological symptoms remains to be evaluated.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
May/12/1998
Abstract
Dehydroepiandrosterone (DHEA) and its sulfate derivative (DHEAS) are the most abundant steroids produced by the human adrenal, but no receptors have been identified for these steroids, and no function for them has been established, other than as precursors for sex steroid synthesis. DHEA and DHEAS are found in brains from many species, and we have shown that enzymes crucial for their synthesis, especially P450c17 (17alpha-hydroxylase/c17,20 lyase), are expressed in a developmentally regulated, region-specific fashion in the developing rodent brain. One region of embryonic expression of P450c17, the neocortical subplate, has been postulated to play a role in guiding cortical projections to their appropriate targets. We therefore determined if products of P450c17 activity, DHEA and DHEAS, regulated the motility and/or growth of neocortical neurons. In primary cultures of mouse embryonic neocortical neurons, DHEA increased the length of neurites containing the axonal marker Tau-1, and the incidence of varicosities and basket-like process formations in a dose-dependent fashion. These effects could be seen at concentrations normally found in the brain. By contrast, DHEAS had no effect on Tau-1 axonal neurites but increased the length of neurites containing the dendritic marker microtubule-associated protein-2. DHEA rapidly increased free intracellular calcium via activation of N-methyl-D-aspartate (NMDA) receptors. These studies provide evidence of mechanisms by which DHEA and DHEAS exert biological actions, show that they have specific functions other than as sex steroid precursors, mediate their effects via non-classic steroid hormone receptors, and suggest that their developmentally regulated synthesis in vivo may play crucial and different roles in organizing the neocortex.
Publication
Journal: Clinical Chemistry
June/23/1991
Abstract
The concentrations of hormones measured in serum from maternal blood change dramatically during pregnancy. While the relative contributions of sex steroids shift from maternal ovaries and adrenals to the fetoplacental unit, other maternal tissues such as pituitary and liver respond to increasing concentrations of estrogen and secrete increasing amounts of prolactin and sex-hormone-binding globulin. To determine longitudinal changes in circulating maternal hormones, we collected blood from 60 women on three occasions during their pregnancies. We observed a 1.7-fold increase in testosterone concentration in serum; concentrations of sex-hormone-binding globulin in serum rose 5.6-fold. The major increase (6.8-fold) in estradiol in serum occurred within the first 16 weeks, followed by a further 4.8-fold increase by term. Mean concentrations of progesterone, 17-hydroxyprogesterone, and androstenedione in serum increased 11.9-, 3-, and 1.3-fold, respectively, whereas concentrations of dehydroepiandrosterone sulfate (DHEAS) fell by 50%. Mean serum prolactin concentrations increased 3.8-fold during the first trimester and by a similar amount during the final 24 weeks of pregnancy. We used these data, obtained from a cohort of women with uncomplicated pregnancies, to construct reference intervals for hormones in maternal serum.
Publication
Journal: Psychoneuroendocrinology
April/4/2004
Abstract
This study investigates basal levels of cortisol and <em>dehydroepiandrosterone</em> (DHEA), and their relation to gender and pubertal development, in healthy children and adolescents. Salivary cortisol and DHEA levels were examined in 129 normally developing subjects aged eight to 16 years. Subjects provided morning (08:00 h) and evening (20:00 h) saliva samples over four consecutive days. Pubertal stage was assessed using Tanner stage sketches, and subjects were grouped according to their general status of pubertal development (pre-early puberty: Tanner stage<III; mid-post puberty: Tanner stage>II). Results showed that morning salivary cortisol in mid-postpubertal girls was greater than in mid-postpubertal boys, but not pre-early pubertal girls and boys. Mean levels of salivary DHEA were greater in mid-postpubertal boys and girls than in pre-early pubertal boys and girls. Changes in hypothalamic-pituitary-adrenal (HPA) axis function that occur during puberty may have implications for immediate and long-term adolescent health.
Publication
Journal: American Journal of Psychiatry
April/20/1999
Abstract
OBJECTIVE
This study was designed to assess possible antidepressant effects of dehydroepiandrosterone (DHEA), an abundant adrenocortical hormone in humans.
METHODS
Twenty-two patients with major depression, either medication-free or on stabilized antidepressant regimens, received either DHEA (maximum dose = 90 mg/day) or placebo for 6 weeks in a double-blind manner and were rated at baseline and at the end of the 6 weeks with the Hamilton Depression Rating Scale. Patients previously stabilized with antidepressants had the study medication added to that regimen; others received DHEA or placebo alone.
RESULTS
DHEA was associated with a significantly greater decrease in Hamilton depression scale ratings than was placebo. Five of the 11 patients treated with DHEA, compared with none of the 11 given placebo, showed a 50% decrease or greater in depressive symptoms.
CONCLUSIONS
These results suggest that DHEA treatment may have significant antidepressant effects in some patients with major depression. Further, larger-scale trials are warranted.
Publication
Journal: Endocrinology
April/15/2004
Abstract
Dehydroepiandrosterone (DHEA) is a precursor to sex steroids such as androstenedione (AE), testosterone (T), and estrogens. DHEA has potent effects on brain and behavior, although the mechanisms remain unclear. One possible mechanism of action is that DHEA is converted within the brain to sex steroids. 3beta-Hydroxysteroid dehydrogenase/Delta5-Delta4 isomerase (3beta-HSD) catalyzes the conversion of DHEA to AE. AE can then be converted to T and estrogen within the brain. We test the hypothesis that 3beta-HSD is expressed in the adult brain in a region- and sex-specific manner using the zebra finch (Taeniopygia guttata), a songbird with robust sex differences in song behavior and telencephalic song nuclei. In zebra finch brain, DHEA is converted by 3beta-HSD to AE and subsequently to estrogens and 5alpha- and 5beta-reduced androgens. 3beta-HSD activity is highest in the diencephalon and telencephalon. In animals killed within 2-3 min of disturbance, baseline 3beta-HSD activity in portions of the telencephalon is higher in females than males. Acute restraint stress (10 min) decreases 3beta-HSD activity in females but not in males, and in stressed animals, telencephalic 3beta-HSD activity is greater in males than in females. Thus, the baseline sex difference is rapidly reversed by stress. To our knowledge, this is the first demonstration of 1) brain region differences in DHEA metabolism by 3beta-HSD, 2) rapid modulation of 3beta-HSD activity, and 3) sex differences in brain 3beta-HSD and regulation by stress. Songbirds are good animal models for studying the regulation and functions of DHEA and neurosteroids in the nervous system.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
April/7/2002
Abstract
To assess whether leptin is an independent predictor of bone mineral density (BMD) in postmenopausal women, we studied the relationships of BMD to serum leptin, 25(OH)D, 1,25(OH)(2)D, PTH, E2, dehydroepiandrosterone sulfate, GH, IGF-I, creatinine clearance, calcium intake, fat mass, and lean mass in 107 women aged 50-90 yr. We also related serum leptin to markers of bone formation [serum bone alkaline phosphatase and osteocalcin (OC)] and resorption (urine C-telopeptide of type I collagen). In stepwise multiple linear regression, lean mass explained 28.5%, age 10.3%, and leptin 7.2% of the whole body BMD variance. Age explained 21.1%, lean mass 12.8%, and leptin 3.7% of the femoral neck BMD variance. After adjustment for fat mass and creatinine clearance, correlations between leptin and bone alkaline phosphatase (positive) and OC (negative) disappeared but, remained significant with urine C-telopeptide of type I collagen (r = -0.27, P < 0.01). Markers of bone formation and resorption were strongly intercorrelated. These data demonstrate that leptin is an independent predictor of whole body and femoral neck BMD in postmenopausal women. Although the relationships between leptin and markers of bone formation appear complex, leptin may exert a protective effect on bone by limiting the excessive bone resorption coupled to bone formation associated with bone loss after menopause.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
December/20/1994
Abstract
The relationships of cigarette smoking, age, relative weight, and dietary intake to serum dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), androstenedione, cortisol, 3-alpha-androstanediol, 3-alpha-androstanediol-glucuronide, testosterone, albumin-bound testosterone, free testosterone, dihydrotestosterone (DHT), and sex hormone-binding globulin (SHBG) were examined cross-sectionally in 1241 randomly sampled middle-aged U.S. men. Compared with nonsmokers and independent of relative weight (body mass index) and age, cigarette smokers had increased serum levels of DHEA (18% higher, P = 0.0002), DHEAS (13% higher, P = 0.0007), cortisol (5% higher, P = 0.01), androstenedione (33% higher, P = 0.0001), testosterone (9% higher, P = 0.009), DHT (14% higher, P = 0.004), and SHBG (8% higher, P = 0.004). Androstenedione, total plasma testosterone, albumin-bound testosterone, DHT, and SHBG decreased with increasing relative weight. Age was positively associated with serum SHBG and negatively associated with albumin-bound testosterone, DHEA, and DHEAS. An association was found between alcohol intake and DHEA (r = 0.15; P = 0.0001), cortisol (r = 0.10; P = 0.0007), and 3-alpha-androstanediol-glucuronide (r = 0.08; P = 0.0004). Cortisol was the only hormone that was associated with carbohydrate intake (r = -0.09; P = 0.002). The only hormones associated with dietary lipids were DHT (for vegetable fat, r = 0.07; P = 0.02), cortisol (for total fat, r = 0.08; P = 0.007), and SHBG (for animal fat, r = -0.06; P = 0.05). In addition, SHBG was positively associated with dietary (r = 0.07; P = 0.008) and crude (r = 0.08; P = 0.007) fiber. These data suggest that serum adrenal steroid and sex hormone concentrations in middle-aged men are more influenced by cigarette smoking, age, and obesity than by dietary intake; however, serum adrenal steroids were influenced by alcohol intake.
Publication
Journal: Pharmacology and Therapeutics
January/27/2008
Abstract
Neurosteroids are a relatively new class of neuroactive compounds brought to prominence in the past 2 decades. Despite knowing of their presence in the nervous system of various species for over 20 years and knowing of their functions as GABA(A) and N-methyl-d-aspartate (NMDA) ligands, new and unexpected functions of these compounds are continuously being identified. Absence or reduced concentrations of neurosteroids during development and in adults may be associated with neurodevelopmental, psychiatric, or behavioral disorders. Treatment with physiologic or pharmacologic concentrations of these compounds may also promote neurogenesis, neuronal survival, myelination, increased memory, and reduced neurotoxicity. This review highlights what is currently known about the neurodevelopmental functions and mechanisms of action of 4 distinct neurosteroids: pregnenolone, progesterone, allopregnanolone, and dehydroepiandrosterone (DHEA).
Publication
Journal: Health Psychology
August/21/2008
Abstract
OBJECTIVE
Numerous studies document that stress accelerates disease processes in a variety of diseases including HIV. As a result, investigators have developed and evaluated interventions to reduce stress as a means to improve health among persons living with HIV. Therefore, the current meta-analysis examines the impact of stress-management interventions at improving psychological, immunological, hormonal, and other behavioral health outcomes among HIV+ adults.
METHODS
This meta-analytic review integrated the results of 35 randomized controlled trials examining the efficacy of 46 separate stress management interventions for HIV+ adults (N=3,077).
METHODS
Effect sizes were calculated for stress processes (coping and social support), psychological/psychosocial (anxiety, depression, distress, and quality of life), immunological (CD4+ counts and viral load), hormonal (cortisol, dehydroepiandrosterone sulfate [DHEA-S], cortisol/DHEA-S ratio, and testosterone) and other behavioral health outcomes (fatigue).
RESULTS
Compared to controls, stress-management interventions reduce anxiety, depression, distress, and fatigue and improve quality of life (d+s=0.16 to 0.38). Stress-management interventions do not appear to improve CD4+ counts, viral load, or hormonal outcomes compared with controls.
CONCLUSIONS
Overall, stress-management interventions for HIV+ adults significantly improve mental health and quality of life but do not alter immunological or hormonal processes. The absence of immunological or hormonal benefits may reflect the studies' limited assessment period (measured typically within 1-week postintervention), participants' advanced stage of HIV (HIV+ status known for an average of 5 years), and/or sample characteristics (predominately male and White participants). Future research might test these hypotheses and refine our understanding of stress processes and their amelioration.
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