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Publication
Journal: Steroids
June/8/2009
Abstract
Testosterone is the major gonadal sex steroid produced by the testes in men. Testosterone is also produced in smaller amounts by the ovaries in women. The adrenal glands produce the weaker androgens dehydroepiandrosterone, dehydroepiandrosterone sulfate, and androstenedione. These androgens collectively affect skeletal homeostasis throughout life in both men and women, particularly at puberty and during adult life. Because testosterone can be metabolized to estradiol by the aromatase enzyme, there has been controversy as to which gonadal sex steroid has the greater skeletal effect. The current evidence suggests that estradiol plays a greater role in maintenance of skeletal health than testosterone, but that androgens also have direct beneficial effects on bone. Supraphysiological levels of testosterone likely have similar effects on bone as lower levels via direct interaction with androgen receptors, as well as effects mediated by estrogen receptors after aromatization to estradiol. Whether high doses of synthetic, non-aromatizable androgens may, in fact, be detrimental to bone due to suppression of endogenous testosterone (and estrogen) levels is a potential concern that warrants further study.
Publication
Journal: Molecular and Cellular Biochemistry
August/11/1994
Publication
Journal: Archives of general psychiatry
August/16/2004
Abstract
BACKGROUND
Recently, a growing body of research has provided evidence that dehydroepiandrosterone sulfate (DHEA-S) is involved in an organism's response to stress and that it may provide beneficial behavioral and neurotrophic effects.
OBJECTIVE
To investigate plasma DHEA-S and cortisol levels, psychological symptoms of dissociation, and military performance.
METHODS
Prospective study.
METHODS
Twenty-five healthy subjects enrolled in military survival school.
RESULTS
The DHEA-S-cortisol ratios during stress were significantly higher in subjects who reported fewer symptoms of dissociation and exhibited superior military performance.
CONCLUSIONS
These data provide prospective, empirical evidence that the DHEA-S level is increased by acute stress in healthy humans and that the DHEA-S-cortisol ratio may index the degree to which an individual is buffered against the negative effects of stress.
Publication
Journal: Trends in Endocrinology and Metabolism
July/27/2004
Abstract
In humans, 3beta-hydroxysteroid dehydrogenase (3beta-HSD), 17beta-HSD and 5alpha-reductase activities in androgen target tissues, such as the prostate and skin, convert dehydroepiandrosterone, androstenedione and testosterone into the most potent natural androgen dihydrotestosterone (DHT). This androgen is converted mainly in situ into two phase I metabolites, androsterone (ADT) and androstane-3alpha,17beta-diol (3alpha-DIOL), which might be back converted to DHT. Here, we discuss the recent findings regarding the characterization of specific UDP-glucuronosyltransferases (UGTs), UGT2B7, B15 and B17, responsible for the glucuronidation of these metabolites. The tissue distribution and cellular localization of the UGT2B transcripts and proteins in humans clearly indicate that these enzymes are synthesized in androgen-sensitive tissues. It is postulated that the conjugating activity of UGT enzymes is the main mechanism for modulating the action of steroids and protecting the androgen-sensitive tissues from deleteriously high concentrations of DHT, ADT and 3alpha-DIOL.
Publication
Journal: Psychological Medicine
August/18/1996
Abstract
The association between basal cortisol, dehydroepiandrosterone (DHEA), its sulphate (DHEAS) and major depression was investigated in 8- to 16-year-olds. Eighty-two subjects with major depression, 25 non-depressed psychiatric cases and 40 community controls were systematically assessed for current mental state and hormone levels at 08.00, 12.00 and 20.00 h, assayed from salivary samples collected over a 48 h period. The average mean of the two time points was compared between the three groups. Evening cortisol hypersecretion and morning DHEA hyposecretion were significantly, and independently, associated with major depression. High evening cortisol >> 0.594 ng/mL) and low morning DHEA (< 0.200 ng/mL) identified subgroups of depressives with different types of adrenal hormone dysregulation. The association between high evening cortisol or low morning DHEA and MDD was not affected by either age or gender.
Publication
Journal: Clinical Endocrinology
May/19/2004
Abstract
Adrenarche refers to the onset of dehydroepiandrosterone (DHEA) and DHEA-sulphate (DHEA-S) production from the adrenal zona reticularis that can be detected at around 6 years of age. The phenotypic result of adrenarche is pubarche or the development of axillary and pubic hair that occurs in both girls and boys at about age 8. The phenomenon of adrenarche is unique to human beings and to some Old World primates, and a reversal of adrenarche appears to occur in the ageing process. Premature and exaggerated adrenarche can be indicative of future onset of adult diseases, thus increasing the clinical relevance of adrenarche. The physiological triggers of adrenarche and the role(s) of DHEA-S remain speculative. However, the biochemical pathways that define adrenarche have been characterized in detail, and the appearance of key enzymes and cofactors in the adrenal zona reticularis track with the progression of adrenarche. This article reviews the clinical manifestations of adrenarche, the biochemistry of the enzymes involved in DHEA-S production, and the cell biology of the adrenal zona reticularis.
Publication
Journal: Journal of Neuroendocrinology
November/22/1999
Abstract
Progesterone facilitates and 5alpha-dihydrotestosterone (DHT) inhibits female sexual behaviour in rodents; their metabolites, 5alpha-pregnan-3alpha-ol-20-one (3alpha,5alpha-THP) and 5alpha-androstane-3alpha-17beta-Diol (3alpha-Diol), may influence the onset and termination of lordosis. Changes in these and related steroids in hormonal states associated with differences in receptivity were investigated. Rats were assigned to oestrus, metoestrus, dioestrus, pro-oestrus, mated, gestational days 5-7, 12-14, 18-20, or post-partum conditions; rats 9+ months of age were considered older. Pro-oestrus rats were exposed to the mating arena, sight and smell of a male with no tactile contact, artificial vaginocervical stimulation, standard mating, or no mating. Progesterone, 5alpha-pregnane-3,20-dione, 3alpha,5alpha-THP, oestradiol, testosterone, DHT, 3alpha-Diol, <em>dehydroepiandrosterone</em>, and corticosterone were measured in plasma and whole brain, midbrain, hypothalamus, cortex, amygdala, hippocampus. 3alpha,5alpha-THP and 3alpha-Diol changed with reproductive state and mating stimuli. Plasma and whole brain 3alpha,5alpha-THP and 3alpha-Diol were significantly increased in pro-oestrus versus dioestrus rats; plasma 3alpha,5alpha-THP was decreased and 3alpha-Diol increased in mated versus pro-oestrus rats. The midbrain and hypothalamus had the most evident changes in 3alpha,5alpha-THP and 3alpha-Diol between dioestrus versus pro-oestrus and pro-oestrus versus mated rats. 3alpha,5alpha-THP and 3alpha-Diol were altered differently in response to mating stimuli. 3alpha,5alpha-THP was greater in the midbrain of mated versus pro-oestrus rats; other mating-relevant stimuli decreased 3alpha,5alpha-THP. Midbrain 3alpha-Diol was increased with exposure to a male <VCS< mating. 3alpha,5alpha-THP was increased and 3alpha-Diol was decreased in the hypothalamus of mated versus pro-oestrus rats; exposure to the various mating stimuli decreased 3alpha,5alpha-THP and 3alpha-Diol. The neurosteroids, 3alpha,5alpha-THP and 3alpha-Diol, vary with mating in the hypothalamus and midbrain of rats.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
July/26/1993
Abstract
To determine the relative ranking of antioxidative potential of various steroids the effect of 14 steroid compounds on the fluorescence of phycoerythrin was monitored over time following the addition of a peroxy radical generator 2,2'-azo-bis (2-amidino-propane) dihydrochloride. The rate of decay of fluorescence in the presence of a 200 nM of 17 beta-estradiol, 17 alpha-estradiol and estriol expressed as percentages of the rate of decay in the absence of these compounds (control curve), were 74.1 +/- 6.3, 84.0 +/- 5.42 and 64.2 +/- 2.53%, respectively (P < 0.005). Cortisone and corticosterone appeared to have very mild pro-oxidant properties. Other steroids tested such as estrone, testosterone, progesterone, androstenedione, dehydroepiandrosterone, cortisol, tetrahydrocortisone, deoxycorticosterone and aldosterone had no significant antioxidant properties. It is concluded that estrogens especially estriol and 17 beta-estradiol are naturally occurring antioxidants.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/1/1988
Abstract
To assess the effects of dehydroepiandrosterone (DHEA) on body fat mass, serum lipid levels, and tissue sensitivity to insulin, five normal men were given placebo and five normal men were given oral DHEA [1600 mg/day (554.7 mmol/day)] for 28 days in a randomized, double blind study. In the DHEA group serum DHEA-S levels rose 2.5- to 3.5-fold, and mean (+/- SEM) serum androstenedione rose from 4.3 +/- 0.6 to 8.6 +/- 1.2 nmol/L (P less than 0.004, by paired t test), but serum total testosterone, free testosterone, sex hormone-binding globulin, estradiol, and estrone levels did not change. In the DHEA group the mean percent body fat decreased by 31%, with no change in weight. This suggests that the reduction in fat mass was coupled with an increase in muscle mass. DHEA administration also resulted in a fall in mean serum total cholesterol concentration (4.82 +/- 0.21 vs. 4.48 +/- 0.29 nmol/L; P less than 0.05), which was due almost entirely to a fall of 7.5% in mean serum low density lipoprotein cholesterol (3.21 +/- 0.11 vs. 2.97 +/- 0.14 nmol/L; P less than 0.01). No changes in anthropometric parameters or serum lipid levels occurred in the placebo group. Tissue sensitivity to insulin, assessed by the hyperinsulinemic-euglycemic clamp technique, did not change in either the placebo or DHEA groups. These results suggest that in normal men DHEA administration reduces body fat, increases muscle mass, and reduces serum low density lipoprotein cholesterol levels. Tissue sensitivity to insulin was unaffected by short term DHEA administration.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
June/3/1998
Abstract
Evidence from animal as well as human studies has suggested that significant sex differences exist in hypothalamus-pituitary-adrenal axis (HPA) activity. As gonadal steroids could be important modulators of HPA sex differences, stress responses were investigated in subjects of advanced age after dehydroepiandrosterone (DHEA) or placebo treatment. After a 2-week treatment with 50 mg DHEA daily or placebo, 75 men and women (mean age, 67.6 yr) were exposed to the Trier Social Stress Test (TSST). The TSST is a brief psychosocial stress that consists of a free speech and mental arithmetic task in front of an audience. The results show that the TSST induced significant increases in ACTH, salivary free cortisol, total plasma cortisol, norepinephrine, and heart rates (all P < 0.0001) as well as decreased positive affect in the elderly (P = 0.0009). Men showed larger stress responses in ACTH (P = 0.004), salivary free cortisol (P = 0.044), and plasma total cortisol (P = 0.076) compared to women. No sex differences were observed in norepinephrine, epinephrine, or heart rate responses. In contrast to ACTH and cortisol response differences, women reported that they were significantly more stressed by the TSST than men (P = 0.0051). Women treated with DHEA showed ACTH stress responses similar to those of men, but significantly enhanced compared to those of women taking placebos (P < 0.009). No other stress response differences emerged between DHEA and placebo groups. Finally, DHEA treatment did not result in an improvement of subjective well-being. We conclude that elderly men show larger HPA responses than women to psychosocial stress, as studied in the TSST. Estrogen effects on hypothalamic CRF-producing neurons might be responsible for these sex differences.
Publication
Journal: American Journal of Physiology - Gastrointestinal and Liver Physiology
September/8/2008
Abstract
Mice deficient in the organic solute transporter (Ost)-alpha subunit of the heteromeric organic solute and steroid transporter, Ostalpha-Ostbeta, were generated and were found to be viable and fertile but exhibited small intestinal hypertrophy and growth retardation. Bile acid pool size and serum levels were decreased by more than 60% in Ostalpha-/- mice, whereas fecal bile acid excretion was unchanged, suggesting a defect in intestinal bile acid absorption. In support of this hypothesis, when [3H]taurocholic acid or [3H]estrone 3-sulfate were administered into the ileal lumen, absorption was lower in Ostalpha-/- mice. Interestingly, serum cholesterol and triglyceride levels were also approximately 15% lower in Ostalpha-/- mice, an effect that may be related to the impaired intestinal bile acid absorption. After intraperitoneal administration of [3H]estrone 3-sulfate or [3H]dehydroepiandrosterone sulfate, Ostalpha-/- mice had higher levels of radioactivity in their liver and urinary bladder and less in the duodenum, indicating altered hepatic, renal, and intestinal disposition. Loss of Ostalpha was associated with compensatory changes in the expression of several genes involved in bile acid homeostasis, including an increase in the multidrug resistance-associated protein 3, (Mrp3)/Abcc3, an alternate basolateral bile acid export pump, and a decrease in cholesterol 7alpha-hydroxylase, Cyp7a1, the rate-limiting enzyme in bile acid synthesis. The latter finding may be explained by increased ileal expression of fibroblast growth factor 15 (Fgf15), a negative regulator of hepatic Cyp7a1 transcription. Overall, these findings provide direct support for the hypothesis that Ostalpha-Ostbeta is a major basolateral transporter of bile acids and conjugated steroids in the intestine, kidney, and liver.
Publication
Journal: Brain research. Molecular brain research
May/12/1999
Abstract
It has been postulated that decreases in plasma levels of dehydroepiandrosterone (DHEA) may contribute to the development of some age-related disorders. Along with neuroprotective and memory enhancing effects, DHEA has been shown to display antioxidant properties. Moreover, oxidative stress is known to cause lipid peroxidation and degenerative changes in the hippocampus, an area involved in memory processes and especially afflicted in Alzheimer's disease (AD). Accordingly, we investigated the antioxidant effects of DHEA in models of oxidative stress using rat primary hippocampal cells and human hippocampal tissue from AD patients and age-matched controls. A pre-treatment of rat primary mixed hippocampal cell cultures with DHEA (10-100 microM) protected against the toxicity induced by H2O2 and sodium nitroprusside. Moreover, DHEA (10-100 microM) was also able to prevent H2O2/FeSO4-stimulated lipid oxidation in both control and AD hippocampal tissues. Taken together, these data suggest that DHEA may be useful in treating age-related central nervous system diseases based on its protective effects in the hippocampus.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
October/2/2003
Abstract
Pulmonary artery (PA) hypertension was studied in a chronic hypoxic-pulmonary hypertension model (7-21 days) in the rat. Increase in PA pressure (measured by catheterism), cardiac right ventricle hypertrophy (determined by echocardiography), and PA remodeling (evaluated by histology) were almost entirely prevented after oral dehydroepiandrosterone (DHEA) administration (30 mg/kg every alternate day). Furthermore, in hypertensive rats, oral administration, or intravascular injection (into the jugular vein) of DHEA rapidly decreased PA hypertension. In PA smooth muscle cells, DHEA reduced the level of intracellular calcium (measured by microspectrofluorimetry). The effect of DHEA appears to involve a large conductance Ca2+-activated potassium channel (BKCa)-dependent stimulatory mechanism, at both function and expression levels (isometric contraction and Western blot), via a redox-dependent pathway. Voltage-gated potassium (Kv) channels also may be involved because the antagonist 4-amino-pyridine blocked part of the DHEA effect. The possible pathophysiological and therapeutic significance of the results is discussed.
Publication
Journal: International Journal of Cancer
August/5/2008
Abstract
Overproduction of reactive oxygen species (ROS), through either endogenous or exogenous sources, could induce DNA damage, and accumulation of DNA damage might lead to multistep carcinogenesis. The antioxidative effects of vitamin D have been suggested by epidemiological and many in vitro and in vivo laboratory studies. While exploring the antioxidative effects of vitamin D in prostate cells, we found that the active form of vitamin D, 1 alpha, 25-dihydroxyvitamin D(3) (1,25-VD), can protect nonmalignant human prostate epithelial cell lines, BPH-1 and RWPE-1, but not malignant human prostate epithelial cells, CWR22R and DU 145, from oxidative stress-induced cell death. Glucose-6-phosphate dehydrogenase (G6PD), a key antioxidant enzyme, was dose- and time-dependently induced by 1,25-VD. Mechanistic studies using chromatin immunoprecipitation (ChIP) assay revealed that a direct repeat-3 (DR3) vitamin D response element located in the first intron of the G6PD genome can be bound by liganded vitamin D receptor, thereby regulating G6PD gene expression. Increasing G6PD activity and glutathione level by 1,25-VD can scavenge cellular ROS. Moreover, the protective effects of 1,25-VD were abolished by dehydroepiandrosterone, a noncompetitive inhibitor of G6PD activity. Together, our results showed that 1,25-VD can protect nonmalignant prostate cells from oxidative stress-induced cell death by elimination of ROS-induced cellular injuries through transcriptional activation of G6PD activity. The antioxidative effect of vitamin D strengthens its roles in cancer chemoprevention and adds to a growing list of beneficial effects of vitamin D against cancer.
Publication
Journal: Biological Psychiatry
January/22/2007
Abstract
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.
Publication
Journal: Annals of the New York Academy of Sciences
August/14/2002
Abstract
Generally, androgens exert suppressive effects on both humoral and cellular immune responses and seem to represent natural anti-inflammatory hormones; in contrast, estrogens exert immunoenhancing activities, at least on humoral immune response. Low levels of gonadal androgens (testosterone/dihydrotestosterone) and adrenal androgens (dehydroepiandrosterone and its sulfate), as well as lower androgen/estrogen ratios, have been detected in body fluids (that is, blood, synovial fluid, smears, salivary) of both male and female rheumatoid arthritis patients, supporting the possibility of a pathogenic role for the decreased levels of the immune-suppressive androgens. Several physiological, pathological, and therapeutic conditions may change the sex hormone milieu and/or peripheral conversion, including the menstrual cycle, pregnancy, the postpartum period, menopause, chronic stress, and inflammatory cytokines, as well as use of corticosteroids, oral contraceptives, and steroid hormonal replacements, inducing altered androgen/estrogen ratios and related effects. Therefore, sex hormone balance is still a crucial factor in the regulation of immune and inflammatory responses, and the therapeutical modulation of this balance should represent part of advanced biological treatments for rheumatoid arthritis and other autoimmune rheumatic diseases.
Publication
Journal: Clinical Chemistry
July/7/2010
Abstract
BACKGROUND
Measurement of serum androgens is important in adult, geriatric, pediatric endocrinology, and oncology patients. We developed a liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay for simultaneous measurement of androstenedione, dehydroepiandrosterone (DHEA), and testosterone in these patients.
METHODS
We spiked 200 muL of serum or plasma with isotope-labeled internal standards and performed extraction with methyl t-butyl ether. We then derivatized the extracts with hydroxylamine and analyzed them by LC-MS/MS using a 2-dimensional chromatographic separation with a 3.5-min analysis time.
RESULTS
Total imprecision for each analyte was <11.2%. Limits of quantification were 10, 50, and 10 ng/L for androstenedione, DHEA, and testosterone, respectively. Reference intervals were established for children (age 6 months to 17 years), men, and women. Androstenedione and DHEA concentrations were lowest in 2- to 3-year-old children. Adult concentrations were achieved in girls at Tanner stage 3 and in boys at Tanner stage 4-5. In premenopausal and (postmenopausal) women the median concentrations of androstenedione, DHEA, and testosterone were 810 (360), 3000 (1670), 270 (180) ng/L, respectively. In postmenopausal women, concentrations of testosterone were age independent, whereas androstenedione and DHEA concentrations decreased with age. In men the median concentrations of androstenedione, DHEA, and testosterone were 440, 2000, and 3700 ng/L, respectively. In men older than 40 years, median concentrations decreased at rates of 5%, 10%, and 20% per decade for androstenedione, DHEA, and testosterone, respectively.
CONCLUSIONS
This LC-MS/MS method has the required lower limit of quantification and specificity for analysis of endogenous concentrations of androgens in all groups studied. Reference intervals were established for healthy children and adults.
Publication
Journal: Cancer Epidemiology Biomarkers and Prevention
December/12/2000
Abstract
Few studies have prospectively examined endogenous hormone levels as risk factors for breast cancer. The present study compares prediagnostic hormone levels using stored serum from breast cancer cases and controls selected from the Life Span Study population of the Radiation Effects Research Foundation in Hiroshima and Nagasaki, Japan. Stored serum samples collected in 1968-1970 were assayed for 72 women subsequently diagnosed with breast cancer and 150 control subjects in 72 case-control sets matched on age, date of blood collection, exposure, radiation dose, and city. Serum levels were determined for sex hormone binding globulin, total estradiol (E2), bioavailable E2, dehydroepiandrosterone sulfate, and prolactin. Matched case-control comparisons of hormone levels were carried out by conditional logistic regression and were adjusted for menopausal status at the time of blood drawing. The odds ratio per unit log change in bioavailable E2 was 2.2 [95% confidence interval (CI), 1.02-5.31 for all subjects, and 2.3 (95% CI, 0.55-6.8) and 2.1 (95% CI, 0.55-9.7), respectively, based only on premenopausal or postmenopausal serum. The estimated odds ratios in each quintile of bioavailable E2 level, using the lowest quintile as referent, were 1.00, 1.89, 1.43, 3.45, and 3.37 (P for trend = 0.035). For sex hormone binding globulin, the overall odds ratio was 0.58 (95% CI, 0.14-2.26), and 1.00 (95% CI, 0.19-5.45) and 0.21 (95% CI, 0.02-1.88) based on premenopausal and postmenopausal serum, respectively. This study offers further prospective support for the hypothesis that a high level of biologically available E2 is a risk factor for the subsequent development of breast cancer.
Publication
Journal: Obesity research
October/27/2004
Abstract
Public health efforts and current antiobesity agents have not controlled the increasing epidemic of obesity. Investigational antiobesity agents consist of 1) central nervous system agents that affect neurotransmitters or neural ion channels, including antidepressants (bupropion), selective serotonin 2c receptor agonists, antiseizure agents (topiramate, zonisamide), some dopamine antagonists, and cannabinoid-1 receptor antagonists (rimonabant); 2) leptin/insulin/central nervous system pathway agents, including leptin analogues, leptin transport and/or leptin receptor promoters, ciliary neurotrophic factor (Axokine), neuropeptide Y and agouti-related peptide antagonists, proopiomelanocortin and cocaine and amphetamine regulated transcript promoters, alpha-melanocyte-stimulating hormone analogues, melanocortin-4 receptor agonists, and agents that affect insulin metabolism/activity, which include protein-tyrosine phosphatase-1B inhibitors, peroxisome proliferator activated receptor-gamma receptor antagonists, short-acting bromocriptine (ergoset), somatostatin agonists (octreotide), and adiponectin; 3) gastrointestinal-neural pathway agents, including those that increase cholecystokinin activity, increase glucagon-like peptide-1 activity (extendin 4, liraglutide, dipeptidyl peptidase IV inhibitors), and increase protein YY3-36 activity and those that decrease ghrelin activity, as well as amylin analogues (pramlintide); 4) agents that may increase resting metabolic rate ("selective" beta-3 stimulators/agonist, uncoupling protein homologues, and thyroid receptor agonists); and 5) other more diverse agents, including melanin concentrating hormone antagonists, phytostanol analogues, functional oils, P57, amylase inhibitors, growth hormone fragments, synthetic analogues of dehydroepiandrosterone sulfate, antagonists of adipocyte 11B-hydroxysteroid dehydrogenase type 1 activity, corticotropin-releasing hormone agonists, inhibitors of fatty acid synthesis, carboxypeptidase inhibitors, indanones/indanols, aminosterols, and other gastrointestinal lipase inhibitors (ATL962). Finally, an emerging concept is that the development of antiobesity agents must not only reduce fat mass (adiposity) but must also correct fat dysfunction (adiposopathy).
Publication
Journal: Annals of Internal Medicine
November/15/1992
Abstract
OBJECTIVE
To compare plasma androgen levels in diabetic and nondiabetic men and to determine their relation to diabetic dyslipidemia.
METHODS
A population-based, case-control study.
METHODS
Community.
METHODS
Men 53 to 88 years of age from the Rancho Bernardo, California, cohort who were screened for diabetes using an oral glucose tolerance test.
METHODS
Plasma androgen levels were compared in 44 men with untreated non-insulin-dependent diabetes mellitus and 88 age-matched men who had a normal glucose tolerance test. The relation of lipid and lipoprotein levels to androgen level and diabetic status was assessed before and after adjusting for covariates.
RESULTS
Men with diabetes had significantly lower plasma levels of free (4.96 nmol/L compared with 5.58 nmol/L) and total testosterone (14.7 nmol/L compared with 17.4 nmol/L), dihydrotestosterone (428 pg/mL compared with 533 pg/mL), and dehydroepiandrosterone sulfate (DHEA-S) (1.92 mumol/L compared with 2.42 mumol/L) than nondiabetic men. They also had significantly lower high-density lipoprotein (HDL) cholesterol and significantly higher triglyceride levels. Differences were not explained by obesity, alcohol use, or cigarette habit. Overall, the total testosterone level, but not the free testosterone level, was positively correlated with the HDL cholesterol level (P = 0.009) and negatively correlated with the triglyceride level (P = 0.0001). Similar associations were seen in analyses restricted to the men without diabetes.
CONCLUSIONS
Lower levels of endogenous androgens are seen in older diabetic men, and low androgen levels are associated with diabetic dyslipidemia.
Publication
Journal: Frontiers in Neuroendocrinology
November/17/2008
Abstract
In 1849, Berthold demonstrated that testicular secretions are necessary for aggressive behavior in roosters. Since then, research on the neuroendocrinology of aggression has been dominated by the paradigm that the brain receives gonadal hormones, primarily testosterone, which modulate relevant neural circuits. While this paradigm has been extremely useful, recent studies reveal important alternatives. For example, most vertebrate species are seasonal breeders, and many species show aggression outside of the breeding season, when gonads are regressed and circulating testosterone levels are typically low. Studies in birds and mammals suggest that an adrenal androgen precursor-dehydroepiandrosterone (DHEA)-may be important for the expression of aggression when gonadal testosterone synthesis is low. Circulating DHEA can be metabolized into active sex steroids within the brain. Another possibility is that the brain can autonomously synthesize sex steroids de novo from cholesterol, thereby uncoupling brain steroid levels from circulating steroid levels. These alternative neuroendocrine mechanisms to provide sex steroids to specific neural circuits may have evolved to avoid the "costs" of high circulating testosterone during particular seasons. Physiological indicators of season (e.g., melatonin) may allow animals to switch from one neuroendocrine mechanism to another across the year. Such mechanisms may be important for the control of aggression in many vertebrate species, including humans.
Publication
Journal: Archives of general psychiatry
February/23/2005
Abstract
BACKGROUND
Alternative and over-the-counter medicines have become increasingly popular choices for many patients who prefer not to take traditional antidepressants. The adrenal androgen and neurosteroid dehydroepiandrosterone (DHEA) is available as over-the-counter hormonal therapy and previously has been reported to have antidepressant-like effects.
OBJECTIVE
To evaluate the efficacy of DHEA as a monotherapy treatment for midlife-onset depression.
METHODS
A double-blind, randomized, placebo-controlled, crossover treatment study was performed from January 4, 1996, through August 31, 2002. Settings The National Institute of Mental Health Midlife Outpatient Clinic in the National Institutes of Health Clinical Center, Bethesda, Md. Patients Men (n = 23) and women (n = 23) aged 45 to 65 years with midlife-onset major or minor depression participated in this study. None of the subjects received concurrent antidepressant medications. Intervention Six weeks of DHEA therapy, 90 mg/d for 3 weeks and 450 mg/d for 3 weeks, and 6 weeks of placebo.
METHODS
The 17-Item Hamilton Depression Rating Scale and Center for Epidemiologic Studies Depression Scale. Additional measures included the Derogatis Interview for Sexual Functioning. Results were analyzed by means of repeated-measures analysis of variance and post hoc Bonferroni t tests.
RESULTS
Six weeks of DHEA administration was associated with a significant improvement in the 17-Item Hamilton Depression Rating Scale and the Center for Epidemiologic Studies Depression Scale ratings compared with both baseline (P<.01) and 6 weeks of placebo treatment (P<.01). A 50% or greater reduction in baseline Hamilton Depression Rating Scale scores was observed in 23 subjects after DHEA and in 13 subjects after placebo treatments. Six weeks of DHEA treatment also was associated with significant improvements in Derogatis Interview for Sexual Functioning scores relative to baseline and placebo conditions.
CONCLUSIONS
We find DHEA to be an effective treatment for midlife-onset major and minor depression.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
August/4/1997
Abstract
A cross-sectional survey was made in 56 exceptionally healthy males, ranging in age from 20 to 84 years. Measurements were made of selected steroidal components and peptidic hormones in blood serum, and cognitive and physical tests were performed. Of those blood serum variables that gave highly significant negative correlations with age (r>> -0.6), bioavailable testosterone (BT), dehydroepiandrosterone sulfate (DHEAS), and the ratio of insulin-like growth factor 1 (IGF-1) to growth hormone (GH) showed a stepwise pattern of age-related changes most closely resembling those of the age steps themselves. Of these, BT correlated best with significantly age-correlated cognitive and physical measures. Because DHEAS correlated well with BT and considerably less well than BT with the cognitive and physical measures, it seems likely that BT and/or substances to which BT gives rise in tissues play a more direct role in whatever processes are rate-limiting in the functions measured and that DHEAS relates more indirectly to these functions. The high correlation of IGF-1/GH with age, its relatively low correlation with BT, and the patterns of correlations of IGF-1/GH and BT with significantly age-correlated cognitive and physical measures suggest that the GH-IGF-1 axis and BT play independent roles in affecting these functions. Serial determinations made after oral ingestion of pregnenolone and data from the literature suggest there is interdependence of steroid metabolic systems with those operational in control of interrelations in the GH-IGF-1 axis. Longitudinal concurrent measurements of serum levels of BT, DHEAS, and IGF-1/GH together with detailed studies of their correlations with age-correlated functional measures may be useful in detecting early age-related dysregulations and may be helpful in devising ameliorative approaches.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/5/1994
Abstract
CRH is synthesized in the hypothalamus and released in response to stress into the portal hypophyseal blood; an additional site of synthesis, the placenta, is present only during pregnancy. Placental CRH is released into the maternal and fetal circulation during human pregnancy, and we hypothesized that the chronic fetal stress associated with fetal growth retardation may stimulate placental CRH release. We measured plasma CRH concentrations in the umbilical cord blood of 28 growth-retarded fetuses and 28 normally grown fetuses matched for gestational age and mode of delivery. Plasma ACTH, dehydroepiandrosterone sulfate (DHEAS), and cortisol were also measured in the umbilical cord samples to determine if CRH levels were correlated with levels of pituitary and adrenal hormones. The mean umbilical cord plasma CRH level in the growth-retarded fetuses was 206 +/- 25.8 pmol/L, which was significantly higher than that in the normally grown fetuses matched for gestational age, presence or absence of labor, and mode of delivery (49.4 +/- 16.7 pmol/L; P < 0.01). The mean plasma ACTH level in the growth-retarded fetuses (5.7 +/- 1.2 pmol/L) was significantly higher than that in the normally grown fetuses (3.3 +/- 0.7 pmol/L; P < 0.05). The mean cortisol concentration in the growth-retarded fetuses was 260 +/- 32.5 nmol/L, and that in the normally grown fetuses was 220 +/- 40 nmol/L. The mean DHEAS level was significantly lower in the growth-retarded fetuses (4.8 +/- 0.6 mumol/L) than that in the normally grown fetuses (7.7 +/- 0.6 mumol/L; P < 0.001). There was a significant correlation between umbilical cord plasma CRH and both ACTH and cortisol concentrations as well as a significant negative correlation between CRH and DHEAS levels in the growth-retarded fetuses. The umbilical cord plasma CRH level is extremely elevated in growth-retarded fetuses compared to that in normal fetuses. Placental CRH, like hypothalamic CRH, may be stimulated in conditions of chronic stress and may modulate fetal pituitary-adrenal function in high risk pregnancies.
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