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Publication
Journal: Best Practice and Research in Clinical Endocrinology and Metabolism
February/11/2002
Abstract
The maintenance of life depends on the capacity of the organism to sustain its equilibrium via allostasis'-the ability to achieve stability through change. Life-threatening disease induces acute adaptive responses specific to the stimulus and generalized responses when the disturbances are prolonged. These changes are associated with increased activity of the hypothalamic-pituitary-adrenal axis and may have survival value in preparing the body for fight or flight'. There is a shift towards an increase in glucocorticoid production and away from mineralocorticoid and androgen production, as well as an increase in the biological effects of glucocorticoids through an increased cortisol free fraction and an increased glucocorticoid receptor sensitivity. During the prolonged phase, there is a dissociation between high plasma cortisol and low adrenocorticotropin hormone levels, suggesting non-adrenocorticotropin hormone-mediated mechanisms for the regulation of the adrenal cortex. This hypercortisolism is in contrast to the very low dehydroepiandrosterone sulphate level, indicating an imbalance between the immunostimulatory and immunosuppressive adrenocortical hormones. The question is whether the total serum cortisol concentration represents sufficient glucocorticoid biological activity during the prolonged phase of critical illness.
Publication
Journal: Endocrinology
December/23/2002
Abstract
Adrenarche is the prepubertal onset of increased adrenal secretion of 19-carbon steroids, especially dehydroepiandrosterone (DHEA). However, while human beings and chimpanzees exhibit adrenarche, other primates such as the baboon and rhesus monkey do not, and the adrenals of most other mammals produce little or no DHEA. Thus, the acquisition of adrenarche is a very recent evolutionary event. DHEA is produced from pregnenolone by the successive 17alpha-hydroxylase and 17,20 lyase activities of a single enzyme, P450c17. To ascertain whether sequence differences in P450c17 contribute to adrenarche, we cloned the rhesus monkey cDNA from adrenal tissue and cloned the chimpanzee and baboon cDNAs from genomic DNA using an exon-trapping strategy. Using microsomes from yeast transformed with rhesus, baboon, chimp, or human P450c17, we measured the Michaelis constant and maximum velocity for the 17alpha-hydroxylase and 17,20 lyase activities. The human and chimp enzymes differ at only two amino acids and baboon and rhesus P450c17 only at a single residue; the human/chimp enzyme differed from the baboon/rhesus enzyme by 25-27 residues (95% identity). Surprisingly, the greatest difference in enzymatic activities was a marked increase in 17alpha-hydroxylase activity of P450c17 in the baboon, which differs from rhesus only at residue 255 [arginine (Arg) in baboon, histine (His) in rhesus]. Residue 255 is also Arg in human and chimp. Wild-type human P450c17 and its Arg255His mutant had similar 17alpha-hydroxylase activities, but the Arg255Ala mutant had decreased 17alpha-hydroxylase activity. These data establish that Arg255 is important for 17alpha-hydroxylase activity and show that the evolution of adrenarche in higher primates is not determined by variations in the sequence of P450c17.
Publication
Journal: Dementia and Geriatric Cognitive Disorders
March/31/2002
Abstract
Hormonal changes during normal aging include decreasing levels of gonadal hormones and adrenal androgens. These hormones influence multiple nervous functions, including cognition and mood. Related to this, abnormalities at several levels of the hypothalamic-pituitary-adrenal axis (HPA) have been reported in patients with Alzheimer's disease (AD). We studied steroid hormones in 33 patients with mild to moderate AD (12 men; 21 women, 76.4 +/- 7.8 years) and 22 healthy elderly controls (10 men; 12 women, 75.4 +/- 7.5 years old, respectively). Basal levels of serum cortisol, dehydroepiandrosterone (DHEA) and androstenedione were significantly increased in AD patients. Women with AD had significantly higher levels of DHEA and androstenedione. Serum estradiol levels were non-significantly increased in women with AD. After adjustment for age and BMI women with AD had significantly increased levels of androstenedione and DHEA. Increased gonadal hormone levels in mild to moderate AD may reflect an increased secretion, and/or alterations in metabolism of these hormones. This may influence the symptomatology and progression of the disease.
Publication
Journal: Nature Reviews Urology
January/8/2012
Abstract
Prostate cancer is the most hormone sensitive of all cancers. However, any hormonal therapeutic strategy must take into account the fact that two almost equivalent sources of androgens act in the prostate, namely testosterone of testicular origin, and the locally produced androgens testosterone and dihydrotestosterone (DHT) derived from dehydroepiandrosterone of adrenal origin. Combined androgen blockade--medical or surgical castration plus a pure antiandrogen--would, therefore, be the logical first-line treatment for prostate cancer, although castration or an antiandrogen alone is still chosen in the majority of cases. Although long-term control, or even cure, is possible when combined androgen blockade is used when the tumor is localized, resistance to treatment invariably develops in patients when start of treatment is delayed until the disease has become metastatic. This observation can be explained either by elevated levels of the androgen receptor, which can increase the response to low levels of androgens and also modify the response to antiandrogens; or by local biosynthesis of androgens. Research to identify new and more potent antiandrogens, as well as blockers of peripheral and adrenal androgen biosynthesis--such as abiraterone--could be of great importance.
Publication
Journal: Current Drug Metabolism
April/21/2008
Abstract
Heart failure is a very serious cardiovascular disease that affects more than five million people in North America. The role of cytochrome P450 (CYP) in cardiovascular health and disease is well established. Many CYP enzymes have been identified in the heart and their levels have been reported to be altered during cardiac hypertrophy and heart failure. There is a great deal of discrepancy between various reports on CYP alterations during heart failure, likely due to differences in disease severity, species in question and other underlying conditions. In general, however, cardiac CYP1B and CYP2A, CYP2B, CYP2E, CYP2J, CYP4A and CYP11 mRNA levels and related enzyme activities are usually increased. Moreover, there is a strong correlation between CYP-mediated endogenous metabolites and the pathogenesis of cardiac hypertrophy and heart failure. Some of these metabolites confer cardioprotective effect such as estradiol, dehydroepiandrosterone, epoxyeicosatrienoic acids, and prostaglandin I(2); whereas, other metabolites may be harmful to the heart such as androgens, aldosterone, hydroxyeicosatetraenoic acids, and thromboxane A(2). On the other hand, heart failure plays an important role in the down-regulation of hepatic CYP involved in drug metabolism through several mechanisms which include hepatocellular damage, hypoxia, elevated levels of pro-inflammatory cytokines, and increased production of heme oxygenase-1. Therefore, more research is needed to elucidate the mechanisms by which CYP affect the development and/or progression of heart failure and also the mechanism by which heart failure alters cardiac and hepatic CYP enzymes.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
April/19/1984
Abstract
The daily hormonal fluctuations that occur simultaneously in the fetus, mother, and amniotic fluid during late gestation and before preterm parturition were studied in long term catheterized rhesus macaques. Blood and amniotic fluid samples were collected twice daily and analyzed by RIA for estrone, estradiol, dehydroepiandrosterone sulfate (DHEAS), progesterone, cortisol, and prostaglandin F2 alpha metabolite (PGFM). Vaginal delivery in monkeys with live fetuses was preceded by rising concentrations of DHEAS in fetal, but not maternal, blood. Parallel increases in fetal plasma estrone, maternal plasma estrone and estradiol, and amniotic fluid estrone preceded the rise in amniotic fluid PGFM (P less than 0.005, by analysis of variance). Cortisol levels remained stable in maternal blood and amniotic fluid, but increased before delivery in fetal blood. Nocturnal progesterone peaks in both fetal and maternal blood increased progressively in magnitude in fetuses before parturition. Rising concentrations of fetal DHEAS, estrone, and progesterone indicated an increase in adrenal activity before parturition in the rhesus fetus. PG production, reflected in amniotic fluid PGFM concentrations, was temporally related to increasing amniotic fluid concentrations of estrone. Although progesterone withdrawal may occur at a local tissue level, parturition occurred without an apparent decrease in circulating maternal, circulating fetal, or amniotic fluid progesterone concentrations.
Publication
Journal: Journal of Neurochemistry
February/17/2008
Abstract
In the songbird brain, dehydroepiandrosterone (DHEA) is metabolized to the active and aromatizable androgen androstenedione (AE) by 3beta-hydroxysteroid dehydrogenase/Delta5-Delta4 isomerase (3beta-HSD). Thus, brain 3beta-HSD plays a key role in regulating the steroidal milieu of the nervous system. Previous studies have shown that stress rapidly regulates brain 3beta-HSD activity in a sex-specific manner. To elucidate endocrine regulation of brain 3beta-HSD, we asked whether 17beta-estradiol (E(2)) regulates DHEA metabolism in adult zebra finch (Taeniopygia guttata) and whether there are sex-specific effects. Brain tissue was homogenized and centrifuged to obtain supernatant lacking whole cells and cell nuclei. Supernatant was incubated with [(3)H]DHEA and radioinert E(2)in vitro. Within only 10 min, E(2) significantly reduced 3beta-HSD activity in both male and female brain. Interestingly, the rapid effects of E(2) were more pronounced in females than males. These are the first data to show a rapid effect of estrogens on the songbird brain and suggest that rapid estrogen effects differ between male and female brains.
Publication
Journal: Kidney International
April/13/2004
Abstract
BACKGROUND
The pathogenesis of ischemia/reperfusion (I/R) involves generation of reactive oxygen and nitrogen species. This in vivo study investigates the effect of dehydroepiandrosterone (DHEA), a physiologic steroid with antioxidant properties, on oxidative balance and renal dysfunctions induced by monolateral I/R.
METHODS
Normal and DHEA-treated rats (4 mg/day x 21 days, orally) were subjected to monolateral renal I/R (30 minutes/6 hours). The oxidative state was determined by measuring hydrogen peroxide level and activities of glutathione-peroxidase, catalase, and superoxide dismutase. Tumor necrosis factor-alpha (TNF-alpha) and nitric oxide production and inducible nitric oxide synthase (iNOS) levels were also measured. Hydroxynonenal content was used to probe lipid peroxidation. Functional parameters determined were creatinine levels and Na/K-ATPase activity. Immunohistochemical and morphologic studies were also performed.
RESULTS
A markedly pro-oxidant state was evident in the kidney of rats subjected to I/R. Both hydrogen peroxide and reactive nitrogen species (nitric oxide and iNOS) increased, whereas antioxidants decreased. Oxidant species induce TNF-alpha increase, which, in turn, produces lipoperoxidative processes, as documented by the increased hydroxynonenal (HNE) level. As final result, impaired renal functionality, hydropic degeneration, and vacuolization of proximal convolute tubules were observed in kidneys of I/R rats. DHEA pretreatment improved the parameters considered.
CONCLUSIONS
I/R induces oxidative stress and consequently damages the proximal convolute renal tubules. Rats supplemented with DHEA and subjected to I/R had reduced pro-oxidant state, oxidative damage, and improved renal functionality, indicating an attenuation of oxidative injury and dysfunctions mediated by I/R.
Publication
Journal: Molecular Endocrinology
November/20/2011
Abstract
Endometrial stromal cells (ESC) must undergo a hormone-driven differentiation to form decidual cells as a requirement of proper embryo implantation. Recent studies from our laboratory have demonstrated that decidualizing cells require glucose transporter 1 expression and an increase in glucose use to complete this step. The present study focuses on the glucose-dependent molecular and metabolic pathways, which are required by ESC for decidualization. Inhibition of glycolysis had no effect on decidualization. However, blockade of the pentose phosphate pathway (PPP) with pharmacologic inhibitors 6-aminonicotinamide or dehydroepiandrosterone (DHEA), and short hairpin RNA-mediated knockdown of glucose-6-phosphate dehydrogenase, the rate-limiting step in the PPP, both led to strong decreases in decidual marker expression in vitro and decreased decidualization in vivo. Additionally, the studies demonstrate that inhibition is due, at least in part, to ribose-5-phosphate depletion, because exogenous nucleoside administration restored decidualization in these cells. The finding that PPP inhibition prevents decidualization of ESC is novel and clinically important, because DHEA is an endogenous hormone produced by the adrenal glands and elevated in a high proportion of women who have polycystic ovary syndrome, the most common endocrinopathy in reproductive age women. Together, this data suggest a mechanistic link between increased DHEA levels, use of glucose via the PPP, and pregnancy loss.
Publication
Journal: Menopause
May/1/2008
Abstract
OBJECTIVE
To describe general and sexual well-being in women with premature ovarian failure (POF) and to investigate whether there is a relationship between androgen levels and sexual functioning.
METHODS
Women with POF and healthy volunteers with regular menstrual cycles participated. Participants completed a written questionnaire and underwent hormonal screening. The questionnaire included standardized measures: the Questionnaire for Screening Sexual Dysfunctions, the Shortened Fatigue Questionnaire, and the Symptom Check List-90. Serum hormone measurements included estradiol, total testosterone, bioavailable testosterone, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone sulfate.
RESULTS
Eighty-one women with POF and 68 control women participated in the study. Compared with control women, women with POF reported more complaints of anxiety, depression, somatization, sensitivity, hostility, and psychological distress. Overall women with POF were less satisfied with their sexual life. They had fewer sexual fantasies and masturbated less frequently. Sexual contact was associated with less sexual arousal, reduced lubrication, and increased genital pain. However, the frequency of desire to have sexual contact and the frequency of actual sexual contact with the partner did not differ between women with POF and control women. Women with POF had lower levels of estradiol, total testosterone, and androstenedione. Multiple regression analysis revealed that androgen levels had only a weak influence on sexual functioning; higher total testosterone levels were associated with increased frequency of desire for sexual contact, and higher androstenedione levels were associated with elevated frequency of sexual contact.
CONCLUSIONS
Women with POF have diminished general and sexual well-being and are less satisfied with their sexual lives than control women. Although women with POF had lower androgen levels, we did not find an important independent role for androgens in various aspects of sexual functioning.
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Publication
Journal: Drug Metabolism and Disposition
March/12/2007
Abstract
The human placenta has both protective and nurturing functions for the fetal organism. Uptake and elimination of xenobiotics and endogenous substances are facilitated by various transport proteins from the solute carrier (SLC) and ABC families, respectively. A functional interaction of uptake and elimination, which is a prerequisite for vectorial transport across cellular barriers, has not been described for placenta. In this study, we examined expression of organic anion transporter (OAT) 4 (SLC22A11), organic anion transporting polypeptide (OATP) 2B1 (SLCO2B1, OATP-B), and breast cancer resistance protein (BCRP) (ABCG2) in human placenta (n = 71) because all three proteins are involved in transmembranal transfer of estrone 3 sulfate (E3S; metabolic product) and dehydroepiandrosterone sulfate (DHEAS; precursor molecule). On the mRNA level, we found a significant correlation of OATP2B1 and BCRP (R(2) = 0.534; p < 0.01) but not between OAT4 and BCRP (R(2) = -0.104; p>> 0.05). Localization studies confirmed basal expression of OATP2B1 and apical expression of BCRP. To study functional interactions between OATP2B1 and BCRP, we developed a Madin-Darby canine kidney cell model expressing both transport proteins simultaneously (OATP2B1 and BCRP in the basal and apical membrane, respectively). Using this cell model in a transwell system resulted in a significantly increased basal to apical transport of both E3S and DHEAS, when both transporters were expressed with no change of transfer in the apical to basal direction. Taken together, these data show the potential for a functional interaction of OATP2B1 and BCRP in transepithelial transport of steroid sulfates in human placenta.
Publication
Journal: Journal of Pharmacology and Experimental Therapeutics
December/14/2004
Abstract
We examined neuroprotective effects of beta-estradiol, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEA-S) against N-methyl-D-aspartate (NMDA)-induced neurotoxicity in primary cultured rat hippocampal neurons. All three steroids demonstrated neuroprotective effects. Time-course studies revealed that steroid cotreatment for only 15 min at the same time as exposure to NMDA, but neither pretreatment nor addition of steroids for 24 h after NMDA-mediated neuroprotective effects. This indicates that short-term actions of these steroids are critical for this process. Acute treatment with beta-estradiol dose dependently inhibited NMDA-induced intracellular Ca(2+) increases, which strongly correlated with its neuroprotective effect via L-type voltage-gated calcium channels. Acute treatment with DHEA, but not with DHEA-S, significantly inhibited nitric oxide (NO) production and Ca(2+)-sensitive NO synthase (NOS) activity caused by NMDA stimulation. An NOS inhibitor, N(G)-monomethyl-L-arginine acetate was also protective against NMDA-induced neurotoxicity. These data indicate that beta-estradiol may exert neuroprotective effects mainly by reducing Ca(2+) increases but that DHEA may act by inhibiting NOS activity. Treatment with the sigma-1 receptor (Sig-1R) antagonists rimcazole or BD1063 (1-[2-(3,4-dichlorophenyl)ethyl]-4-methylpiperazine dihydrochloride) partially, but significantly, reversed the neuroprotective effect of DHEA-S against NMDA-induced neurotoxicity, whereas muscimol, a GABA-A-receptor agonist, did not. This suggests that the neuroprotective effect of DHEA-S may be mediated via Sig-1R, at least in part. Together, our data suggest that the neurosteroid family members beta-estradiol, DHEA, and DHEA-S exert neuroprotective effects through different nongenomic mechanisms.
Publication
Journal: Molecular Medicine
May/8/2013
Abstract
Current endocrine treatment for advanced prostate cancer does not result in a complete ablation of adrenal androgens. Adrenal androgens can be metabolized by prostate cancer cells, which is one of the mechanisms associated with progression to castration-resistant prostate cancer (CRPC). Aldo-keto reductase family 1 member C3 (AKR1C3) is a steroidogenic enzyme that plays a crucial role in the conversion of adrenal androgen dehydroepiandrosterone (DHEA) into high-affinity ligands for the androgen receptor (testosterone [T] and dihydrotestosterone [DHT]). The aim of this study was to examine whether AKR1C3 could be used as a marker and therapeutic target for CRPC. AKR1C3 mRNA and protein levels were upregulated in CRPC tissue, compared with benign prostate and primary prostate cancer tissue. High AKR1C3 levels were found only in a subset of CRPC patients. AKR1C3 can be used as a biomarker for active intratumoral steroidogenesis and can be measured in biopsy or transurethral resection of the prostate specimens. DuCaP (a CRPC cell line that has high AKR1C3 expression levels) used and converted DHEA under hormone-depleted conditions into T and DHT. The DHEA-induced growth of DuCaP could be antagonized by indomethacine, an inhibitor of AKR1C3. This study indicates that AKR1C3 can be considered a therapeutic target in a subgroup of patients with high AKR1C3 expression.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/19/2009
Abstract
BACKGROUND
Women with primary or secondary adrenal insufficiency report a decreased health-related quality of life (HRQOL) despite traditional adrenal replacement therapy. Dehydroepiandrosterone (DHEA) has been studied as an agent to improve HRQOL in these patients.
OBJECTIVE
We sought to conduct a systematic review and meta-analysis of randomized controlled trials of DHEA effects on HRQOL in women with adrenal insufficiency.
METHODS
We searched electronic databases (MEDLINE, EMBASE, Cochrane CENTRAL, Web of Science, CINAHL, and PsycInfo) and reference lists of eligible studies through July 2008.
METHODS
Eligible trials randomly assigned women with primary or secondary adrenal insufficiency to either DHEA or control and measured the effect of treatment on HRQOL.
METHODS
Reviewers working independently and in duplicate assessed the methodological quality of trials and collected data on patient characteristics, interventions, and outcomes.
RESULTS
We found 10 eligible trials that measured HRQOL and depression, anxiety, and sexual function. Random-effects meta-analysis showed a small improvement in HRQOL in women treated with DHEA compared with placebo [effect size of 0.21; 95% confidence interval, 0.08 to 0.33; inconsistency (I(2)) = 32%]. There was a small beneficial effect of DHEA on depression; effects on anxiety and sexual well-being were also small and not statistically significant.
CONCLUSIONS
DHEA may improve, in a small and perhaps trivial manner, HRQOL and depression in women with adrenal insufficiency. There was no significant effect of DHEA on anxiety and sexual well-being. The evidence appears insufficient to support the routine use of DHEA in women with adrenal insufficiency.
Publication
Journal: Journal of Pain
February/21/2007
Abstract
Dehydroepandrosterone (DHEA)-dehydroepiandrosterone sulfate (DHEAS) deficiency often produces fatigue, depression, weakness, and sexual dysfunction, which improve during replacement therapy. DHEAS deficiency is a sensitive marker for generalized adrenal insufficiency, but it has not been related to opioid ingestion. DHEAS values were determined in 34 male and 32 female opioid-consuming outpatients aged 35-78 years, in stable health, and in 33 male and 53 female nonopioid-consuming control subjects. No subjects used anticonvulsants or corticosteriod medications, and none had malignant, collagen-vascular, or endocrine disease other than menopause or opioid-induced androgen deficiency. Adrenocorticotropic hormone (ACTH) values were measured in 94 of 152 subjects. DHEAS levels were lower in opioid consumers than in control subjects in a dose-related pattern (P < .01), were below age-specific norms in 67% of opioid consumers and 8% of controls (P < .001), and were below our laboratory's lowest detection limit (15 mug/dL) in 29% of opioid users and 1% of controls (P < .001). DHEAS values were also lower in opioid-consuming nonsmokers than in smokers (P < .05) and were unrelated to body mass index or concurrent hormonal replacement therapy. ACTH levels were normal and unrelated to opioid use. The combination of subnormal DHEAS levels in the presence of normal ACTH values in most opioid-consuming patients suggests that these low levels result from factors other than diminished adrenal ACTH stimulation.
CONCLUSIONS
The study documents a dose-related DHEAS deficiency in a majority of nonhospitalized adults who are chronically consuming sustained-action oral or transdermal opioids for control of nonmalignant pain. This deficiency in these patients has not previously been recognized and is probably symptomatic. Evaluation of replacement therapy should receive high priority.
Publication
Journal: Urology
April/7/2008
Abstract
OBJECTIVE
To identify adrenocortical hormone abnormalities as indicators of endocrine dysfunction in chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS).
METHODS
We simultaneously measured the serum concentrations of 12 steroids in patients with CP/CPPS and controls, using isotope dilution liquid chromatography, followed by atmospheric pressure photospray ionization and tandem mass spectrometry.
RESULTS
We evaluated 27 patients with CP/CPPS and 29 age-matched asymptomatic healthy controls. In the mineralocorticoid pathway, progesterone was significantly greater, and the corticosterone and aldosterone concentrations were significantly lower, in the patients with CP/CPPS than in the controls. In the glucocorticoid pathway, 11-deoxycortisol was significantly lower and the cortisol concentrations were not different between the patients and controls. In the sex steroid pathway, the androstenedione and testosterone concentrations were significantly greater in those with CP/CPPS than in the controls. The estradiol, dehydroepiandrosterone, and dehydroepiandrosterone sulfate concentrations were not different between the patients and controls. The National Institutes of Health-Chronic Prostatitis Symptom Index total and pain domain scores correlated positively with the 17-hydroxyprogesterone and aldosterone (P <0.001) and negatively with the cortisol (P <0.001) concentrations.
CONCLUSIONS
Our results suggest reduced activity of CYP21A2 (P450c21), the enzyme that converts progesterone to corticosterone and 17-hydroxyprogesterone to 11-deoxycortisol. Furthermore, these results provide insights into the biologic basis of CP/CPPS. Follow-up studies should explore the possibility that patients with CP/CPPS meet the diagnostic criteria for nonclassic congenital adrenal hyperplasia and whether the hormonal findings improve or worsen in parallel with symptom severity.
Publication
Journal: American Journal of Physiology - Endocrinology and Metabolism
May/17/2005
Abstract
Dehydroepiandrosterone (DHEA) exerts beneficial effects on blood glucose levels and insulin sensitivity in obese rodents and humans, resembling the effects of peroxisome proliferator-activated receptor-gamma (PPARgamma) ligands and opposing those of glucocorticoids; however, the underlying mechanisms remain unclear. Glucocorticoids are reactivated locally by 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1), which is currently considered as a promising target for the treatment of obesity and diabetes. Using differentiated 3T3-L1 adipocytes, we show that DHEA causes downregulation of 11beta-HSD1 and dose-dependent reduction of its oxoreductase activity. The effects of DHEA were comparable with those of the PPARgamma agonist rosiglitazone but not additive. Furthermore, DHEA reduced the expression of hexose-6-phosphate dehydrogenase, which stimulates the oxoreductase activity of 11beta-HSD1. These findings were confirmed in white adipose tissue and in liver from DHEA-treated C57BL/6J mice. Analysis of the transcription factors involved in the DHEA-dependent regulation of 11beta-HSD1 expression revealed a switch in CCAAT/enhancer-binding protein (C/EBP) expression. C/EBPalpha, a potent activator of 11beta-HSD1 gene transcription, was downregulated in 3T3-L1 adipocytes and in liver and adipose tissue of DHEA-treated mice, whereas C/EBPbeta and C/EBPdelta, attenuating the effect of C/EBPalpha, were unchanged or elevated. Our results further suggest a protective effect of DHEA on adipose tissue by upregulating PPARalpha and downregulating leptin, thereby contributing to the reduced expression of 11beta-HSD1. In summary, we provide evidence that some of the anti-diabetic effects of DHEA may be caused through inhibition of the local amplification of glucocorticoids by 11beta-HSD1 in adipose tissue.
Publication
Journal: Arthritis and rheumatism
October/21/1996
Abstract
OBJECTIVE
To determine if dehydroepiandrosterone (DHEA) is beneficial in the treatment of systemic lupus erythematosus (SLE).
METHODS
In a double-blind, placebo-controlled, randomized trial, 28 female patients with mild to moderate SLE were given DHEA 200 mg/day or placebo for 3 months. Outcomes included the SLE Disease Activity Index (SLEDAI) score, patient's and physician's overall assessments of disease activity, and concurrent corticosteroid dosages (which were adjusted as clinically indicated).
RESULTS
In the patients who were receiving DHEA, the SLEDAI score, patient's and physician's overall assessment of disease activity, and concurrent prednisone dosage decreased, while in the patients taking placebo, small increases were seen. The difference in patient's assessment between the groups was statistically significant (P = 0.022, adjusted). Lupus flares occurred more frequently in the placebo group (P = 0.053). Mild acne was a frequent side effect of DHEA.
CONCLUSIONS
DHEA may be useful as a therapeutic agent for the treatment of mild to moderate SLE. Further studies of DHEA in the treatment of SLE are warranted.
Publication
Journal: Clinical Endocrinology
May/11/1992
Abstract
OBJECTIVE
We wanted to measure forearm mineral density and bone-related biochemical variables in patients with Klinefelter's syndrome.
METHODS
Measurements made in patients with Klinefelter's syndrome were compared to those obtained in age-matched normal male volunteers.
METHODS
We studied 22 patients with Klinefelter's syndrome (12 of whom had received sex hormone therapy) and 22 control subjects.
METHODS
We measured forearm mineral density, forearm fat content, fat-corrected forearm mineral density, plasma calcium and ionized calcium, serum osteocalcin, testosterone and dehydroepiandrosterone sulphate, and urinary hydroxyproline/creatinine ratio.
RESULTS
Forearm mineral density was lower in the Klinefelter's group than in the control subjects (P less than 0.05) and below the control range in 5 patients. The fat content of the forearm was greater in the Klinefelter's group (P less than 0.002). Serum osteocalcin and testosterone were lower, while ionized calcium and the urinary hydroxyproline/creatinine ratio were higher in the Klinefelter's group (P less than 0.002). Serum dehydroepiandrosterone sulphate and testosterone were significantly related in the Klinefelter's group (r = 0.64, P less than 0.001), but not in the controls (r = 0.22, NS). Forearm mineral density and fat-corrected forearm mineral density were significantly related to serum testosterone in the Klinefelter's group (r less than 0.63; P less than 0.01), but not in the control subjects (r less than 0.03, NS).
CONCLUSIONS
Decreased bone density occurs in about 25% of patients with Klinefelter's syndrome and probably reflects both decreased bone formation and increased bone resorption.
Publication
Journal: Metabolism: Clinical and Experimental
May/22/1995
Abstract
Polycystic ovary (PCO) syndrome is strongly associated with insulin resistance and the accompanying adverse metabolic profile. To distinguish the mechanisms of this association, we determined the interactions of PCO with obesity and the influence of ameliorating direct androgenic actions via short-term treatment with the antiandrogen flutamide. Insulin sensitivity was determined by the hyperinsulinemic euglycemic clamp in groups of lean and obese PCO women and weight-matched controls. Compared with control values, insulin-mediated glucose utilization in PCO women was significantly lower in lean (1.96 +/- 0.17 v 1.24 +/- 0.10, P < .01) and obese (1.23 +/- 0.18 v 1.03 +/- 0.09 mmol/m2/min, P < .01) subjects. ANOVA indicated that the effects of obesity and androgenicity are independent and additive. In both lean and obese PCO women, treatment with flutamide for 1 or 3 months markedly improved the clinical and biochemical androgenic features, but did not significantly influence the overall insulin sensitivity. A large disparity between individuals in the response to treatment correlated significantly with a simultaneous reduction in plasma levels of dehydroepiandrosterone sulfate (DHEA-S). Thus in women, PCO and obesity exert synergistic effects on insulin resistance. The decreased insulin sensitivity is mediated via indirect androgenic actions or nonandrogenic mechanisms. In some individuals, a direct effect of androgens might have been masked by a decrease in DHEA-S levels.
Publication
Journal: Ageing Research Reviews
October/13/2004
Abstract
Dehydroepiandrosterone (DHEA) is an abundantly produced adrenal steroid whose biological role has never been clarified. DHEA is a potent uncompetitive inhibitor of mammalian glucose-6-phosphate dehydrogenase (G6PDH) and as a consequence lowers NADPH levels and reduces NADPH-dependent oxygen-free radical production. Overproduction of oxygen-free radicals, or oxidative stress, upregulates inflammation and cellular proliferation and is believed to play a critical role in the development of cancer, atherosclerosis, and Alzheimer's disease, as well as the basic aging process. Both in vitro and in vivo experimental studies strongly indicate that DHEA and related steroids inhibit inflammation and associated epithelial hyperplasia, carcinogenesis, and atherosclerosis, at least in part, through the inhibition of G6PDH and oxygen-free radical formation. Recent epidemiological findings in Sardinian males bearing the Mediterranean variant of G6PDH deficiency are consistent with the hypothesis that reduced G6PDH activity has a beneficial effect on age-related disease development and longevity. Clinical trials with DHEA are encumbered by the high oral doses required as well as the conversion of DHEA into active androgens. The use of less androgenic congeners as well as non-oral formulations may facilitate testing of this class of compounds.
Publication
Journal: Journal of Sexual Medicine
September/18/2013
Abstract
BACKGROUND
Besides hypogonadism, other endocrine disorders have been associated with male sexual dysfunction (MSD).
OBJECTIVE
To review the role of the pituitary hormone prolactin (PRL), growth hormone (GH), thyroid hormones, and adrenal androgens in MSD.
METHODS
A systematic search of published evidence was performed using Medline (1969 to September 2011). Oxford Centre for Evidence-Based Medicine-Levels of Evidence (March 2009) was applied when possible.
METHODS
The most important evidence regarding the role played by PRL, GH, thyroid, and adrenal hormone was reviewed and discussed.
RESULTS
Only severe hyperprolactinemia (>35 ng/mL or 735 mU/L), often related to a pituitary tumor, has a negative impact on sexual function, impairing sexual desire, testosterone production, and, through the latter, erectile function due to a dual effect: mass effect and PRL-induced suppression on gonadotropin secretion. The latter is PRL-level dependent. Emerging evidence indicates that hyperthyroidism is associated with an increased risk of premature ejaculation and might also be associated with erectile dysfunction (ED), whereas hypothyroidism mainly affects sexual desire and impairs the ejaculatory reflex. However, the real incidence of thyroid dysfunction in subjects with sexual problems needs to be evaluated. Prevalence of ED and decreased libido increase in acromegalic patients; however, it is still a matter of debate whether GH excess (acromegaly) may create effects due to a direct overproduction of GH/insulin-like growth factor 1 or because of the pituitary mass effects on gonadotropic cells, resulting in hypogonadism. Finally, although dehydroepiandrosterone (DHEA) and its sulfate have been implicated in a broad range of biological derangements, controlled trials have shown that DHEA administration is not useful for improving male sexual function.
CONCLUSIONS
While the association between hyperprolactinemia and hypoactive sexual desire is well defined, more studies are needed to completely understand the role of other hormones in regulating male sexual functioning.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
May/3/2012
Abstract
In order to overcome many limitations of immunoassays, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) has the potential to find its place in the clinical laboratory medicine for quantification of steroid hormones. A prerequisite for the application of a new analytical procedure in clinical diagnostics is standardization to minimize analytical intra- and interlaboratory variability and inaccuracy. We evaluate a newly standardized HPLC-MS/MS assay in kit-format, developed for routine determination of 16 steroid hormones in human serum samples. Fifteen metabolites can be measured quantitatively, which include aldosterone, androstenedione, androsterone, corticosterone, cortisol, cortisone, 11-deoxycortisol, dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), 17β-estradiol (E2), estrone (E1), etiocholanolone, 17α-hydroxyprogesterone (17OHP), progesterone, and testosterone. 11-Deoxycorticosterone is the only compound rated as semi-quantitative in this kit. The sample preparation is performed by solid phase extraction (SPE) on a 96-well plate. The standardized assay has been validated for human serum in terms of lower and upper limit of quantification (LLOQ 0.01-32 ng/mL, ULOQ 5-8000 ng/mL), linear correlation coefficient of calibration (R(2)>0.9966), intra- and inter-day precision (intra-day 1.1-8.8%, inter-day 5.2-14.8% and 8.2-18.6% for 11-deoxycorticosterone), accuracy (intra-day 88.3-115.5% and 109.3-128.2% for 11-deoxycorticosterone, inter-day 91.4-117.2% and 102.3-137.1% for 11-deoxycorticosterone), analytical total error (3.6-17.8%), proficiency test accuracy (85.4-113.4%), recovery (68-99%), and metabolite stability (freeze/thaw stability 95.5-108.1%, short term stability 86.9-107.2%). Inter-assay comparison with a routine reference HPLC-MS/MS assay and seven immunoassays demonstrates the outstanding high performance of this HPLC-MS/MS based kit by improvements in accuracy for progesterone, androstenedione, and 17OHP. Finally, results of two metyrapone tests demonstrate the potential of the standardized HPLC-MS/MS assay for the analysis of a comprehensive steroid hormone profile in clinical diagnostics.
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Publication
Journal: Biochimica et Biophysica Acta - General Subjects
June/9/2003
Abstract
Hippocampal pyramidal neurons and granule neurons of adult male rats are equipped with a complete machinery for the synthesis of pregnenolone, dehydroepiandrosterone, 17beta-estradiol and testosterone as well as their sulfate esters. These brain neurosteroids are synthesized by cytochrome P450s (P450scc, P45017alpha and P450arom) from endogenous cholesterol. Synthesis is acutely dependent on the Ca(2+) influx attendant upon neuron-neuron communication via N-methyl-D-aspartate (NMDA) receptors. Pregnenolone sulfate, estradiol and corticosterone rapidly modulate neuronal signal transduction and the induction of long-term potentiation via NMDA receptors and putative membrane steroid receptors. Brain neurosteroids are therefore promising neuromodulators that may either activate or inactivate neuron-neuron communication, thereby mediating learning and memory in the hippocampus.
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