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Publication
Journal: Sports Medicine
February/25/2004
Abstract
This article reviews the evidence-based ergogenic potential and adverse effects of 14 of the most common products in use by recreational and elite athletes today. Both legal and prohibited products are discussed. This is an aggressively marketed and controversial area of sports medicine worldwide. It is therefore prudent for the clinician to be well versed in the more popular supplements and drugs reputed to be ergogenic in order to distinguish fact from fiction.Antioxidants, proteins and amino acids are essential components of diet, but additional oral supplementation does not increase endurance or strength. Caffeine is ergogenic in certain aerobic activities. Creatine is ergogenic in repetitive anaerobic cycling sprints but not running or swimming. Ephedrine and pseudoephedrine may be ergogenic but have detrimental cardiovascular effects. Erythropoietin is ergogenic but increases the risk of thromboembolic events. beta-Hydroxy-beta-methylbutyrate has ergogenic potential in untrained individuals, but studies are needed on trained individuals. Human growth hormone and insulin growth factor-I decrease body fat and may increase lean muscle mass when given subcutaneously. Pyruvate is not ergogenic. The androgenic precursors androstenedione and dehydroepiandrosterone have not been shown to increase any parameters of strength and have potentially significant adverse effects. Anabolic steroids increase protein synthesis and muscle mass but with many adverse effects, some irreversible. Supplement claims on labels of product content and efficacy can be inaccurate and misleading.
Authors
Publication
Journal: Cancer Epidemiology Biomarkers and Prevention
June/19/2000
Abstract
We conducted studies to determine the magnitude and sources of variability in androgen assay results and to identify laboratories capable of performing such assays for large epidemiological studies. We studied androstanediol (ADIOL), androstanediol glucuronide (ADIOL G), androstenedione (ADION), androsterone glucuronide (ANDRO G), androsterone sulfate (ANDRO S), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEA S), dihydrotestosterone (DHT), and testosterone (TESTO). A single sample of plasma was obtained from five postmenopausal women, five premenopausal women in the midfollicular phase of the menstrual cycle, and five women in the midluteal phase, divided into aliquots, and stored at -70 degrees. Four sets of two coded aliquots from each woman were then sent to participating labs for analysis at monthly intervals over 4 months. Using the logarithm of assay measurements, we estimated the components of variance and three measures of reproducibility. The usual coefficient of variation is a function of the components that are under the control of the laboratory. The intraclass correlation between measurements for a given individual is the proportion of the total variability that is associated with individuals. The minimum detectable relative difference is important to evaluate study feasibility. Results suggest that a single sample of ADIOL G, DHEA, DHEA S, and ANDRO G (with two lab replicates per sample) can be used to discriminate reliably among women in a given menstrual phase or menopausal status. The results for DHT, TESTO, ADION, and ANDRO S are more problematic and suggest that the present measurement techniques should be used with care, especially with midluteal phase women. The results for ADIOL suggest that this assay is not yet ready for use in epidemiological studies.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
March/14/2007
Abstract
The marked decline in serum dehydroepiandrosterone (DHEA) with age is believed to play a role in health problems associated with aging, these health issues being potentially preventable or reversible by the exogenous administration of DHEA. In the present study, liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) and gas chromatrography/mass spectrometry (GC/MS) were used to measure the serum levels of DHEA and 11 of its metabolites in seventy-five 60-65-year-old Caucasian women who received 3g of 0.1%, 0.3%, 1.0% or 2.0% DHEA cream or placebo applied twice daily on the face, upper chest, arms and legs. The serum levels of DHEA increased 574% over control at the 2.0% DHEA dose while the sum of the androgen metabolites androsterone glucuronide (ADT-G), 3alpha-androstenediol-3G (3alpha-diol-3G) and 3alpha-diol-17G increased by only 231%. On the other hand, serum testosterone and dihydrosterone were increased by 192% and 275%, respectively, above basal levels compared to 139% and 158% for estrone and estradiol. Such data show that the transformation of exogenous DHEA in postmenopausal women is preferentially into androgens rather than into estrogens. On the other hand, the present data indicate that serum DHEA measurements following DHEA supplementation in postmenopausal women are an overestimate of the formation of active androgens and estrogens and suggest a decreased efficiency of transformation of DHEA into androgens and estrogens with aging.
Publication
Journal: American Journal of Epidemiology
June/25/1997
Abstract
The authors examined the relation between postmenopausal serum levels of testosterone and dehydroepiandrosterone sulfate (DHEAS) and subsequent risk of breast cancer in a case-control study nested within the New York University Women's Health Study cohort. A specific objective of their analysis was to examine whether androgens had an effect on breast cancer risk independent of their effect on the biologic availability of estrogen. A total of 130 cases of breast cancer were diagnosed prior to 1991 in a cohort of 7,054 postmenopausal women who had donated blood and completed questionnaires at a breast cancer screening clinic in New York City between 1985 and 1991. For each case, two controls were selected, matching the case on age at blood donation and length of storage of serum specimens. Biochemical analyses were performed on sera that had been stored at -80 degrees C since sampling. The present report includes a subset of 85 matched sets, for whom at least 6 months had elapsed between blood donation and diagnosis of the case. In univariate analysis, testosterone was positively associated with breast cancer risk (odds ratio (OR) for the highest quartile = 2.7, 95% confidence interval (CI) 1.1-6.8, p < 0.05, test for trend). However, after including % estradiol bound to sex hormone-binding globulin (SHBG) and total estradiol in the statistical model, the odds ratios associated with higher levels of testosterone were considerably reduced, and there was no longer a significant trend (OR for the highest quartile = 1.2, 95% CI 0.4-3.5). Conversely, breast cancer risk remained positively associated with total estradiol levels (OR for the highest quartile = 2.9, 95% CI 1.0-8.3) and negatively associated with % estradiol bound to SHBG (OR for the highest quartile = 0.05, 95% CI 0.01-0.19) after adjustment for serum testosterone levels. These results are consistent with the hypothesis that testosterone has an indirect effect on breast cancer risk, via its influence on the amount of bioavailable estrogen. No evidence was found of an association between DHEAS and risk of breast cancer in postmenopausal women.
Publication
Journal: Atherosclerosis
February/23/1997
Abstract
Published studies dealing with the relationship between circulating levels of testosterone and dehydroepiandrosterone (sulfate) (DHEA(S)) and coronary heart disease (CHD) in males, as well as corresponding experimental animal studies are reviewed. One randomized intervention study, eight prospective and 30 cross-sectional studies have evaluated this relationship. In the intervention study, testosterone undecanoate given orally significantly improved angina pectoris in 62 patients with CHD as compared to placebo. No significant association between serum testosterone and CHD was reported in the prospective studies, whereas those studies concerning DHEAS found either no or an inverse association with CHD. Of 30 cross-sectional studies, 18 reported reduced concentrations of testosterone (primarily), and/or DHEA(S) in CHD patients as compared to normals, 11 found similar circulating levels of these androgens in controls and patients with CHD, and one study found elevated levels of DHEA(S) in patients. Animal studies (six male rabbits and one in male chicks) suggest an anti-atherogenic effect of testosterone and DHEA. In conclusion, one intervention, eight cohort and several cross-sectional studies suggest either a neutral or a favourable effect of testosterone and DHEA(S) on CHD in males.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
November/25/1999
Abstract
Dehydroepiandrosterone (DHEA), an androgenic steroid hormone, exhibits an age-related decline. Perimenopausal women have only approximately 50% of peak DHEA levels. Despite limited scientific data, DHEA has gained recognition as a dietary supplement to reduce the symptoms of aging and improve well-being. This randomized, double-blind placebo-controlled trial examined the effects of 50 mg/day of oral DHEA supplementation, for 3 months, on 60 perimenopausal women with complaints of altered mood and well-being. Changes in the serum endocrine profile of women in the DHEA group were significantly greater than the placebo group, including a 242% [95% confidence interval (CI) +60.1, +423.9] increase in DHEAS, a 94.8% (95% CI +34.2, +155.4) increase in testosterone, and a 13.2% (95% CI -27.88, +0.5) decline in cortisol compared to baseline. Women receiving DHEA had a 10.1% (95% CI -15.0, -5.1) decline in high-density lipoprotein and an 18.1% (95% CI -32.2, -3.9) decline in Lp(a) from baseline, but these declines did not significantly differ from women who received placebo. Women receiving DHEA did not have any improvements significantly greater than placebo in the severity of perimenopausal symptoms, mood, dysphoria, libido, cognition, memory, or well-being. DHEA supplementation significantly effects the endocrine profile, may affect the lipid profile, but does not improve perimenopausal symptoms or well-being compared to placebo.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
August/24/2009
Abstract
BACKGROUND
A previous report from the Study of Women Across the Nation indicated a rise in dehydroepiandrosterone sulfate (DHEAS) during the menopausal transition using data from three annual visits.
OBJECTIVE
Our objective was to examine changes in DHEAS with chronological and ovarian aging, expanding the original analyses to include 10 yr of annual data.
METHODS
A longitudinal observational study and cross-sectional analyses of baseline data were conducted. OUTCOME MEASURES AND SUBJECTS: DHEAS, age, menopause status, ethnicity, smoking, weight, and height were assessed in 2886 women from five ethnic groups aged 42-52 yr at entry. Hysterectomy, bilateral oophorectomy, and hormone use were excluded.
RESULTS
Cross-sectional analysis at baseline showed a linear decline in circulating log-transformed DHEAS with increasing age for either the entire cohort (2.81% per year) or for individual ethnicities. A similar negative association with baseline age (2.44% decline per year) was seen in longitudinal linear mixed modeling including observations from premenopause through late postmenopause, an additional 0.33% decline/year. In contradistinction, a late-transition rise in DHEAS was detected when the same women were analyzed by ovarian status. The average increase in mean circulating DHEAS level between early and late menopause transition, beyond changes predicted by aging, was 3.95%, followed by an average decline of 3.96% during the late postmenopause. Approximately 84.5% of the women had an estimated within-woman increase in DHEAS from premenopause/early perimenopause to late perimenopause/early postmenopause.
CONCLUSIONS
These observations underscore differences between cross-sectional and longitudinal studies and the importance of considering ovarian status. Additional investigations regarding adrenal contribution to sex steroids in mid-aged women are warranted.
Publication
Journal: Biochemistry
December/2/2012
Abstract
Human SULT2A1 is one of two predominant sulfotransferases in liver and catalyzes transfer of the sulfuryl moiety (-SO(3)) from activated sulfate (PAPS, 3'-phosphoadenosine 5-phosphosulfate) to hundreds of acceptors (metabolites and xenobiotics). Sulfation recodes the biologic activity of acceptors by altering their receptor interactions. The molecular basis on which these enzymes select and sulfonate specific acceptors from complex mixtures of competitors in vivo is a long-standing issue in the SULT field. Raloxifene, a synthetic steroid used in the prevention of osteoporosis, and dehydroepiandrosterone (DHEA), a ubiquitous steroid precusor, are reported to be sulfated efficiently by SULT2A1 in vitro, yet unlike DHEA, raloxifene is not sulfated in vivo. This selectivity was explored in initial rate and equilibrium binding studies that demonstrate pronounced binding antisynergy (21-fold) between PAPS and raloxifene, but not DHEA. Analysis of crystal structures suggests that PAP binding restricts access to the acceptor-binding pocket by restructuring a nine-residue segment of the pocket edge that constricts the active site opening, or "pore", that sieves substrates on the basis of their geometries. In silico docking predicts that raloxifene, which is considerably larger than DHEA, can bind only to the unliganded (open) enzyme, whereas DHEA binds both the open and closed forms. The predictions of these structures with regard to substrate binding are tested using equilibrium and pre-steady-state ligand binding studies, and the results confirm that a nucleotide-driven isomerization controls access to the acceptor-binding pocket and plays an important role in substrate selection by SULT2A1 and possibly other sulfotransferases.
Publication
Journal: Epilepsia
August/14/2008
Abstract
OBJECTIVE
Seizure exacerbation in catamenial epilepsy (CE) is associated with the decrease in progesterone secretion and increase in estradiol secretion during the premenstrual period. Moreover, experimental evidence suggests that tetrahydrodeoxycorticosterone (THDOC), a positive modulator of the type A receptor for gamma-aminobutyric acid (GABA), and dehydroepiandrosterone sulfate (DHEAS), a negative modulator of this receptor, might play a crucial role in modulating seizure frequency during the menstrual cycle. Following these studies it seems of interest to investigate possible variations, among other hormonal parameters, of THDOC and DHEAS in CE patients.
METHODS
The serum concentrations of progesterone (P4), pregnenolone, allopregnanolone (AP), THDOC, DHEAS, cortisol, and DHEAS/cortisol ratio were measured throughout the menstrual cycle at the 7th, 11th, 15th, 19th, 23rd, and 27th day from the onset of spontaneous menstrual blood loss in young premenopausal women with CE (n = 17) and age-matched controls (n = 13).
RESULTS
At each time of the study, the serum concentration of THDOC and the DHEAS/cortisol ratio were lower (p < 0.05) in women with CE than in control women. The concentrations of P4, pregnenolone, and AP did not differ between the two groups of subjects.
CONCLUSIONS
The reduced serum concentration of THDOC and the reduced DHEAS/cortisol ratio detected throughout the menstrual cycle in women with CE might play a role in CE. Moreover, the peculiar pattern of CE seizure exacerbation might suggest that these neuroendocrine variations are worth investigating in other epileptic syndromes, particularly in those characterized by relevant and uncontrolled variations in seizure frequency.
Publication
Journal: Pediatric Research
September/21/1977
Abstract
Placental steroid sulfatase deficiency is a genetic disorder only recently reported in the medical literature. Most documented cases of placental sulfatase deficiency have been marked by delay in onset of labor, lack of cervical dilatation, and relative refractoriness of oxytocic agents and amniotomy. We have studied the placenta, cultured fibroblasts, and amniotic fluid cells from an affected patient. The activities of estrone sulfatase, pregnenolone sulfatase, dehydroepiandrosterone sulfatase, and arylsulfatase C in the placenta from the patient were severely deficient. Arylsulfatases A and B were present at levels within the normal range for this tissue. Fibroblast dehydroepiandrosterone sulfatase activity was virtually absent in the patient's cells and present at normal levels in individuals with a variety of lysosomal disorders. It would thus appear that the mutation responsible for steroid sulfatase deficiency is genetically and biochemically distinct from those involved in the lysosomal sulfatase deficiency states. The cell culture studies further suggest that the defect is a generalized one which should be detectable in midtrimester of pregnancy and may have phenotypic consequences in later postnatal life.
Publication
Journal: Journal of Biological Chemistry
February/11/2015
Abstract
The human cytochrome P450 17A1 (CYP17A1) enzyme operates at a key juncture of human steroidogenesis, controlling the levels of mineralocorticoids influencing blood pressure, glucocorticoids involved in immune and stress responses, and androgens and estrogens involved in development and homeostasis of reproductive tissues. Understanding CYP17A1 multifunctional biochemistry is thus integral to treating prostate and breast cancer, subfertility, blood pressure, and other diseases. CYP17A1 structures with all four physiologically relevant steroid substrates suggest answers to four fundamental aspects of CYP17A1 function. First, all substrates bind in a similar overall orientation, rising ∼60° with respect to the heme. Second, both hydroxylase substrates pregnenolone and progesterone hydrogen bond to Asn(202) in orientations consistent with production of 17α-hydroxy major metabolites, but functional and structural evidence for an A105L mutation suggests that a minor conformation may yield the minor 16α-hydroxyprogesterone metabolite. Third, substrate specificity of the subsequent 17,20-lyase reaction may be explained by variation in substrate height above the heme. Although 17α-hydroxyprogesterone is only observed farther from the catalytic iron, 17α-hydroxypregnenolone is also observed closer to the heme. In conjunction with spectroscopic evidence, this suggests that only 17α-hydroxypregnenolone approaches and interacts with the proximal oxygen of the catalytic iron-peroxy intermediate, yielding efficient production of dehydroepiandrosterone as the key intermediate in human testosterone and estrogen synthesis. Fourth, differential positioning of 17α-hydroxypregnenolone offers a mechanism whereby allosteric binding of cytochrome b5 might selectively enhance the lyase reaction. In aggregate, these structures provide a structural basis for understanding multiple key reactions at the heart of human steroidogenesis.
Publication
Journal: Brazilian Journal of Medical and Biological Research
November/15/2000
Abstract
Childhood adrenocortical tumors (ACT) are rare. In the USA, only about 25 new cases occur each year. In Southern Brazil, however, approximately 10 times that many cases are diagnosed each year. Most cases occur in the contiguous states of São Paulo and Paraná. The cause of this higher rate has not been identified. Familial genetic predisposition to cancer (p53 mutations) and selected genetic syndromes (Beckwith-Wiedemann syndrome) have been associated with childhood ACT in general but not with the Brazilian counterpart. Most of the affected children are young girls with classic endocrine syndromes (virilizing and/or Cushing). Levels of urinary 17-ketosteroids and plasma dehydroepiandrosterone sulfate (DHEA-S), which are abnormal in approximately 90% of the cases, provide the pivotal clue to a diagnosis of ACT. Typical imaging findings of pediatric ACT consist of a large, well-defined suprarenal tumor containing calcifications with a thin capsule and central necrosis or hemorrhage. The pathologic classification of pediatric ACT is troublesome. Even an experienced pathologist can find it difficult to differentiate carcinoma from adenoma. Surgery is the single most important procedure in the successful treatment of ACT. The role of chemotherapy in the management of childhood ACT has not been established although occasional tumors are responsive to mitotane or cisplatin-containing regimens. Because of the heterogeneity and rarity of the disease, prognostic factors have been difficult to establish in pediatric ACT. Patients with incomplete tumor resection or with metastatic disease at diagnosis have a dismal prognosis. In patients with localized and completely resected tumors, the size of the tumor has predictive value. Patients with large tumors have a much higher relapse rate than those with small tumors.
Publication
Journal: Journals of Gerontology - Series A Biological Sciences and Medical Sciences
April/15/2002
Abstract
Thirty cross-trained, female subjects (19-69 years) completed an endurance exercise session (ES), a resistance exercise session (RS), and a control session (CS) in a randomized, balanced design. The ES consisted of 40 minutes of cycling at 75% maximum heart rate, and the RS consisted of 3 sets of 10 repetitions of eight exercises. During the CS, subjects performed no exercise. Before and after exercise, and after 30 minutes of recovery, blood samples were analyzed for plasma lactate and serum growth hormone, insulin-like growth factor 1, testosterone, estradiol, dehydroepiandrosterone, and cortisol. Samples were taken during the CS at the same intervals as during the exercise sessions. There were no age-related differences in intensity measures during exercise. Absolute change from baseline in testosterone (p <.001), estradiol (p <.05), and growth hormone (p <.01) was significantly greater in the ES and RS compared with that in the CS. Absolute change in dehydroepiandrosterone was significantly greater in the RS only (p <.05). Results indicate that an acute bout of exercise can increase concentrations of anabolic hormones in females across a wide age range.
Publication
Journal: Journal of Biological Chemistry
January/4/2004
Abstract
The gene for human hydroxysteroid sulfotransferase (SULT2B1) encodes two peptides, SULT2B1a and SULT2B1b, that differ only at their amino termini. SULT2B1b has a predilection for cholesterol but is also capable of sulfonating pregnenolone, whereas SULT2B1a preferentially sulfonates pregnenolone and only minimally sulfonates cholesterol. We have determined the crystal structure of SULT2B1a and SULT2B1b bound to the substrate donor product 3'-phosphoadenosine 5'-phosphate at 2.9 and 2.4 A, respectively, as well as SULT2B1b in the presence of the acceptor substrate pregnenolone at 2.3 A. These structures reveal a different catalytic binding orientation for the substrate from a previously determined structure of hydroxysteroid sulfotransferase (SULT2A1) binding dehydroepiandrosterone. In addition, the amino-terminal helix comprising residues Asp19 to Lys26, which determines the specificity difference between the SULT2B1 isoforms, becomes ordered upon pregnenolone binding, covering the substrate binding pocket.
Publication
Journal: Physiology and Behavior
July/9/1995
Abstract
Corticosterone increases with aging but pregnenolone, dehydroepiandrosterone, and testosterone decrease. The marked decrease in hormones that occurs with aging may contribute to the age-related deficit in learning and memory. Administration of these hormones after training was found to improve long-term memory processing in normal young mice. SAMP8 (P8) mice show an age-related loss of learning and memory for a variety of tasks whereas age-matched control mice of the closely related SAMR1 (R1) strain do not. In this study, we found an age-related decrease in serum testosterone levels of 71% between P8 mice 4 and 12 months of age, but only a 26% decrease between R1 mice of the same ages. The difference between the P8 mice was significant (p < 0.01) and the difference between the R1 mice was not. The decrease in testosterone in 12-month-old P8 mice was not accompanied by gross morphological change in the testes. A SC testosterone implant, sufficient to increase plasma testosterone levels to 414 +/- 25 ng/dl, alleviated impaired learning and memory of a foot shock avoidance task in P8 mice. Castration of 4-month-old P8 mice did not produce a deterioration in learning and memory, indicating that low levels of testosterone per se are not responsible for the impairment seen in 12-month-old P8 mice. This suggests that impaired cognitive functioning of the older P8 mice was due to an interaction of aging and reduced testosterone levels.
Publication
Journal: Journal of Nutrition
August/7/2007
Abstract
The purpose of this study was to determine the effects of soy protein isolate consumption on circulating hormone profiles and hormone receptor expression patterns in men at high risk for developing advanced prostate cancer. Fifty-eight men were randomly assigned to consume 1 of 3 protein isolates containing 40 g/d protein: 1) soy protein isolate (SPI+) (107 mg/d isoflavones); 2) alcohol-washed soy protein isolate (SPI-) (<6 mg/d isoflavones); or 3) milk protein isolate (0 mg/d isoflavones). For 6 mo, the men consumed the protein isolates in divided doses twice daily as a partial meal replacement. Serum samples collected at 0, 3, and 6 mo were analyzed for circulating estradiol, estrone, sex hormone-binding globulin, androstenedione, androstanediol glucuronide, dehydroepiandrosterone sulfate, dihydrotestosterone, testosterone, and free testosterone concentrations by RIA. Prostate biopsy samples obtained pre- and postintervention were analyzed for androgen receptor (AR) and estrogen receptor-beta expression by immunohistochemistry. At 6 mo, consumption of SPI+ significantly suppressed AR expression but did not alter estrogen receptor-beta expression or circulating hormones. Consumption of SPI- significantly increased estradiol and androstenedione concentrations, and tended to suppress AR expression (P = 0.09). Although the effects of SPI- consumption on estradiol and androstenedione are difficult to interpret and the clinical relevance is uncertain, these data show that AR expression in the prostate is suppressed by soy protein isolate consumption, which may be beneficial in preventing prostate cancer.
Publication
Journal: Atherosclerosis
August/15/2010
Abstract
OBJECTIVE
Recent epidemiological studies have found that testosterone deficiency is associated with higher mortality largely due to cardiovascular (CV) disease in community-dwelling older men. We investigated whether a low plasma testosterone level could predict cardiovascular events in middle-aged Japanese men with coronary risk factors.
METHODS
One hundred and seventy-one male outpatients (30-69 years old, mean+/-SD=48+/-13 years) who had any coronary risk factor (hypertension, diabetes, dyslipidemia, smoking, and obesity) without a previous history of CV disease were followed up. At baseline, the subjects underwent examination of coronary risk factors, measurement of flow-mediated dilation (FMD) of the brachial artery as an indicator of vascular endothelial function and assays of plasma total testosterone, dehydroepiandrosterone-sulfate (DHEA-S), estradiol and cortisol.
RESULTS
During the mean follow-up period of 77 months, a total of 20 CV events occurred. Kaplan-Meier survival analysis by tertile of plasma hormone levels revealed that the subjects with the lowest testosterone tertile were more likely to develop CV events than those with the highest tertile (P<0.01 by log-rank test). Cox proportional hazards models showed that the subjects with the lowest tertile of plasma testosterone (<14.2 nmol/L) had an approximately 4-fold higher CV event risk compared to those with the higher testosterone tertiles after adjustment for coronary risk factors including medication and FMD (unadjusted hazard ratio, 3.61; 95% CI, 1.47-8.86: multivariate-adjusted hazard ratio, 4.61; 95% CI, 1.02-21.04). Multivariate analysis did not show any significant association of DHEA-S, estradiol or cortisol with CV events.
CONCLUSIONS
A low plasma testosterone level is associated with CV events in middle-aged Japanese men, independent of coronary risk factors and endothelial function. This is the first report to show the relationship between endogenous testosterone and CV events in Asian population.
Publication
Journal: Cochrane Database of Systematic Reviews
March/29/2016
Abstract
BACKGROUND
Infertility is a condition affecting 10% to 15% of couples of reproductive age. It is generally defined as "the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected sexual intercourse". The treatment of infertility may involve manipulation of gametes or of the embryos themselves. These techniques are together known as assisted reproductive technology (ART). Practitioners are constantly seeking alternative or adjunct treatments, or both, in the hope that they may improve the outcome of assisted reproductive techniques. This Cochrane review focusses on the adjunct use of synthetic versions of two naturally-produced hormones, dehydroepiandrosterone (DHEA) and testosterone (T), in assisted reproduction.DHEA and its derivative testosterone are steroid hormones proposed to increase conception rates by positively affecting follicular response to gonadotrophin stimulation, leading to greater oocyte yields and, in turn, increased chance of pregnancy.
OBJECTIVE
To assess the effectiveness and safety of DHEA and testosterone as pre- or co-treatments in subfertile women undergoing assisted reproduction.
METHODS
We searched the following electronic databases, trial registers and websites up to 12 March 2015: the Cochrane Central Register of Controlled Trials (CENTRAL), the Menstrual Disorders and Subfertility Group (MDSG) Specialised Register, MEDLINE, EMBASE, PsycINFO, CINAHL, electronic trial registers for ongoing and registered trials, citation indexes, conference abstracts in the Web of Science, PubMed and OpenSIGLE. We also carried out handsearches. There were no language restrictions.
METHODS
We included randomised controlled trials (RCTs) comparing DHEA or testosterone as an adjunct treatment to any other active intervention, placebo, or no treatment in women undergoing assisted reproduction.
METHODS
Two review authors independently selected studies, extracted relevant data and assessed them for risk of bias. We pooled studies using fixed-effect models. We calculated odds ratios (ORs) for each dichotomous outcome. Analyses were stratified by type of treatment. There were no data for the intended groupings by dose, mode of delivery or after one/more than one cycle.We assessed the overall quality of the evidence for the main findings using the GRADE working group methods.
RESULTS
We included 17 RCTs with a total of 1496 participants. Apart from two trials, the trial participants were women identified as 'poor responders' to standard IVF protocols. The included trials compared either testosterone or DHEA treatment with placebo or no treatment.When DHEA was compared with placebo or no treatment, pre-treatment with DHEA was associated with higher rates of live birth or ongoing pregnancy (OR 1.88, 95% CI 1.30 to 2.71; eight RCTs, N = 878, I² statistic = 27%, moderate quality evidence). This suggests that in women with a 12% chance of live birth/ongoing pregnancy with placebo or no treatment, the live birth/ongoing pregnancy rate in women using DHEA will be between 15% and 26%. However, in a sensitivity analysis removing trials at high risk of performance bias, the effect size was reduced and no longer reached significance (OR 1.50, 95% CI 0.88 to 2.56; five RCTs, N = 306, I² statistic = 43%). There was no evidence of a difference in miscarriage rates (OR 0.58, 95% CI 0.29 to 1.17; eight RCTs, N = 950, I² statistic = 0%, moderate quality evidence). Multiple pregnancy data were available for five trials, with one multiple pregnancy in the DHEA group of one trial (OR 3.23, 95% CI 0.13 to 81.01; five RCTs, N = 267, very low quality evidence).When testosterone was compared with placebo or no treatment we found that pre-treatment with testosterone was associated with higher live birth rates (OR 2.60, 95% CI 1.30 to 5.20; four RCTs, N = 345, I² statistic = 0%, moderate evidence). This suggests that in women with an 8% chance of live birth with placebo or no treatment, the live birth rate in women using testosterone will be between 10% and 32%. On removal of studies at high risk of performance bias in a sensitivity analysis, the remaining study showed no evidence of a difference between the groups (OR 2.00, 95% CI 0.17 to 23.49; one RCT, N = 53). There was no evidence of a difference in miscarriage rates (OR 2.04, 95% CI 0.58 to 7.13; four RCTs, N = 345, I² = 0%, low quality evidence). Multiple pregnancy data were available for three trials, with four events in the testosterone group and one in the placebo/no treatment group (OR 3.09, 95% CI 0.48 to 19.98; three RCTs, N = 292, very low quality evidence).One study compared testosterone with estradiol and reported no evidence of a difference in live birth rates (OR 2.06, 95% CI 0.43 to 9.87; one RCT, N = 46, very low quality evidence) or miscarriage rates (OR 0.70, 95% CI 0.11 to 4.64; one RCT, N = 46, very low quality evidence).The quality of the evidence was moderate, the main limitations being lack of blinding in the included trials, inadequate reporting of study methods, and low event and sample sizes in some trials.
CONCLUSIONS
In women identified as poor responders undergoing ART, pre-treatment with DHEA or testosterone may be associated with improved live birth rates. The overall quality of the evidence is moderate. There is insufficient evidence to draw any conclusions about the safety of either androgen. Definitive conclusions regarding the clinical role of either androgen awaits evidence from further well-designed studies.
Publication
Journal: Journal of Internal Medicine
August/9/2004
Abstract
OBJECTIVE
Elevated cortisol levels are associated with confusion and poor outcome after stroke. Dehydroepiandrosterone sulphate (DS), the most abundant adrenal androgen may act as an anti-glucocorticoid. An altered regulation of these steroids may affect numerous brain functions, including neuronal survival. The purpose of this study was to investigate serum cortisol and DS levels and the cortisol/DS ratio early after stroke and relate our findings to the presence of disorientation and mortality.
METHODS
Patients with acute ischaemic stroke (n = 88, 56 men and 32 women) admitted to a stroke unit were investigated with repeated clinical assessments and scores for degree of confusion, extent of paresis and level of functioning. Serum cortisol (C) and DS were measured on day 1 and/or day 4. Data for 28-day and 1-year mortality are presented. A control group of 65 age-matched healthy individuals was used. Multivariate analyses of mortality rates in the different tertiles or sixtiles of serum cortisol were performed with logistic regression, adjusting for age, sex, diabetes and level of consciousness.
RESULTS
There was no difference in serum cortisol levels on day 1 for stroke patients when compared with control group values. Initial cortisol levels were significantly higher in the patients with acute disorientation versus orientated patients (P < 0.05). Cortisol levels on day 1 were an independent predictor of 28-day mortality, and patients with low cortisol levels (<270 nmol L(-1)) and increased levels (>550 nmol L(-1)) both had an increased 1-year mortality. DS levels on day 1 were significantly elevated in stroke patients.
CONCLUSIONS
Hypercortisolism is associated with cognitive dysfunction early after ischaemic stroke. High and low circulating cortisol levels are associated with increased mortality after stroke. DS levels were not associated with clinical outcome.
Publication
Journal: Cancer Research
June/24/1986
Abstract
Alkaline phosphatase activity in human endometrial cancer cells of the estrogen-responsive Ishikawa line was markedly stimulated (3-20-fold in 4 days) by estrogens, 5 alpha-dihydrotestosterone, and dehydroepiandrosterone but not by testosterone, medroxyprogesterone acetate, glucocorticoids, several peptide hormones, prostaglandins, or growth factors. Maximum responses to estradiol were obtained at concentrations between 10(-9) and 10(-7) M; at 10(-8) M estradiol, the highest activity was reached 48-72 h after addition of the hormone. A linear relationship between enzyme activity at 48 h and the length of exposure to the hormone was observed. Dibutyryl cyclic guanosine 3':5'-monophosphate, but not dibutyryl cyclic adenosine 3':5'-monophosphate enhanced alkaline phosphatase activity and acted synergistically with estradiol. trans-4-Monohydroxytamoxifen completely antagonized the stimulatory effect of estradiol and had no agonistic activity. Dihydrotestosterone and dehydroepiandrosterone appear to exert their effects, at least in part, by interacting with estrogen receptors, since the simultaneous presence in the medium of monohydroxytamoxifen abolished their influence on alkaline phosphatase activity. The specific antiandrogen monohydroxyflutamide partially antagonized the effect of these hormones, suggesting that their action involved androgenic mechanisms as well. Exposure to elevated temperature and to specific inhibitors identified alkaline phosphatase of Ishikawa cells as a placental-type isoenzyme, thus contrasting with the nonplacental type found in glandular epithelial cells of normal endometrium and in another human endometrial cancer cell line, HEC-50. This study extends our previous observations of estrogen responsiveness in the Ishikawa cell line. In addition to the previously reported stimulatory effects on growth and progesterone receptor levels, we are now describing the stimulation by estrogens and C19 steroids of an enzyme, alkaline phosphatase, which can be used as a convenient end point to examine mechanisms of hormonal action.
Publication
Journal: Journal of Biological Chemistry
September/16/2007
Abstract
We have cloned human sodium-dependent organic anion transporter (SOAT) cDNA, which consists of 1502 bp and encodes a 377-amino acid protein. SOAT shows 42% sequence identity to the ileal apical sodium-dependent bile acid transporter ASBT and 33% sequence identity to the hepatic Na(+)/taurocholate-cotransporting polypeptide NTCP. Immunoprecipitation of a SOAT-FLAG-tagged protein revealed a glycosylated form at 46 kDa that decreased to 42 kDa after PNGase F treatment. SOAT exhibits a seven-transmembrane domain topology with an outside-to-inside orientation of the N-terminal and C-terminal ends. SOAT mRNA is most highly expressed in testis. Relatively high SOAT expression was also detected in placenta and pancreas. We established a stable SOAT-HEK293 cell line that showed sodium-dependent transport of dehydroepiandrosterone sulfate, estrone-3-sulfate, and pregnenolone sulfate with apparent K(m) values of 28.7, 12.0, and 11.3 microm, respectively. Although bile acids, such as taurocholic acid, cholic acid, and chenodeoxycholic acid, were not substrates of SOAT, the sulfoconjugated bile acid taurolithocholic acid-3-sulfate was transported by SOAT-HEK293 cells in a sodium-dependent manner and showed competitive inhibition of SOAT transport with an apparent K(i) value of 0.24 mum. Several nonsteroidal organosulfates also strongly inhibited SOAT, including 1-(omega-sulfooxyethyl)pyrene, bromosulfophthalein, 2- and 4-sulfooxymethylpyrene, and alpha-naphthylsulfate. Among these inhibitors, 2- and 4-sulfooxymethylpyrene were competitive inhibitors of SOAT, with apparent K(i) values of 4.3 and 5.5 microm, respectively, and they were also transported by SOAT-HEK293 cells.
Publication
Journal: Endocrine
April/6/2003
Abstract
In the present study, we have explored, in vitro, the possibility that short exposure to androgens and estrogens for 24 h may directly influence leptin expression (ARNm and secretion) in sc adipose tissue from men and women. In men, only dihydrotestosterone at high concentration (100 nM) induced a reduction in leptin secretion and ob mRNA level. In women, 17beta-estradiol (10-100 nM) increased ob mRNA expression (+180 to +500%) and leptin release (+75%). Moreover, in adipose tissue of women, the estrogen precursors testosterone (100 nM) and dehydroepiandrosterone (1 microM) also induced an increase in leptin secretion (+84 and +96%, respectively), an effect that was prevented by the aromatase inhibitor letrozole. Finally, the stimulatory effect of 17beta-estradiol observed in women was antagonized by the antiestrogen ICI182780. Altogether, these results suggest that the sexual dimorphism of leptinemia in humans is mainly owing to the estrogen receptor-dependent stimulation of leptin expression in adipose tissue by estrogens and estrogen precursors in women.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
December/1/2005
Abstract
BACKGROUND
Recent data indicate that women affected by the polycystic ovary syndrome (PCOS) are at greater risk for cardiovascular disease and that metformin may improve the metabolic alterations in these patients.
OBJECTIVE
The objective of this study was to evaluate the effects of 6 months of metformin administration on endothelial structure and function in women with PCOS.
METHODS
This was a prospective, baseline-controlled, clinical study.
METHODS
The study was performed at University Federico II (Naples, Italy).
METHODS
Thirty young normal-weight women with PCOS without additional metabolic or cardiovascular diseases were studied.
METHODS
Metformin (850 mg daily) was administered for 6 months.
METHODS
The main outcome measures were complete hormonal profile, including total testosterone, SHBG, dehydroepiandrosterone sulfate, prolactin, and gonadotropin levels; serum insulin and glucose levels during a 75-g 2-h oral glucose tolerance test; plasma endothelin-1 concentrations (picomoles per liter +/- sd); serum lipid profile; brachial artery baseline diameter (millimeters +/- sd), diameter after reactive hyperemia (millimeters +/- sd), and flow-mediated dilation (percentage +/- sd); and the intima media thickness (millimeters +/- sd) on both common carotid arteries.
RESULTS
After treatment, SHBG levels and the free androgen index changed significantly (P < 0.001). High-density lipoproteins and the area under curve for glucose/area under curve for insulin ratio also significantly (P < 0.001) increased, whereas low-density lipoproteins and plasma endothelin-1 levels were significantly (P < 0.001) reduced. No other change was found in any of the biochemical parameters evaluated. A significant difference was observed in brachial artery baseline diameter (3.24 +/- 0.30 vs. 3.0 +/- 0.30), flow-mediated dilation (14.30 +/- 1.90 vs. 15.70 +/- 1.50) (P < 0.01, each), diameter after reactive hyperemia (3.70 +/- 0.30 vs. 3.55 +/- 0.10) (P < 0.05), and intima media thickness (0.53 +/- 0.09 vs. 0.40 +/- 0.07) (P < 0.001) after metformin treatment in comparison with baseline values.
CONCLUSIONS
A 6-month course of metformin improves endothelial structure and function in young, normal-weight women with PCOS.
Publication
Journal: Biochimica et Biophysica Acta - General Subjects
August/9/2010
Abstract
The neurosteroid allopregnanolone has pronounced neuroprotective actions, increases myelination, and enhances neurogenesis. Evidence suggests that allopregnanolone dysregulation may play a role in the pathophysiology of Alzheimer's disease (AD) and other neurodegenerative disorders. Our prior data demonstrate that allopregnanolone is reduced in prefrontal cortex in male patients with AD compared to male cognitively intact control subjects, and inversely correlated with neuropathological disease stage (Braak and Braak). We therefore determined if allopregnanolone levels are also reduced in AD patients compared to control subjects in temporal cortex, utilizing a larger set of samples from both male and female patients. In addition, we investigated if neurosteroids are altered in subjects who are APOE4 allele carriers. Allopregnanolone, dehydroepiandrosterone (DHEA), and pregnenolone levels were determined in temporal cortex postmortem samples by gas chromatography/mass spectrometry, preceded by high performance liquid chromatography (40 subjects with AD/41 cognitively intact control subjects). Allopregnanolone levels are reduced in temporal cortex in patients with AD (median 2.68 ng/g, n=40) compared to control subjects (median 5.64 ng/g, n=41), Mann-Whitney p=0.0002, and inversely correlated with Braak and Braak neuropathological disease stage (Spearman r=-0.38, p=0.0004). DHEA and pregnenolone are increased in patients with AD compared to control subjects. Patients carrying an APOE4 allele demonstrate reduced allopregnanolone levels in temporal cortex (Mann-Whitney p=0.04). In summary, our findings indicate that neurosteroids are altered in temporal cortex in patients with AD and related to neuropathological disease stage. In addition, the APOE4 allele is associated with reduced allopregnanolone levels. Neurosteroids may be relevant to the neurobiology and therapeutics of AD.
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