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Publication
Journal: Archives of internal medicine
December/20/2007
Abstract
BACKGROUND
Aging in men is characterized by a progressive decline in levels of anabolic hormones, such as testosterone, insulinlike growth factor 1 (IGF-1), and dehydroepiandrosterone sulfate (DHEA-S). We hypothesized that in older men a parallel age-associated decline in bioavailable testosterone, IGF-1, and DHEA-S secretion is associated with higher mortality independent of potential confounders.
METHODS
Testosterone, IGF-1, DHEA-S, and demographic features were evaluated in a representative sample of 410 men 65 years and older enrolled in the Aging in the Chianti Area (InCHIANTI) study. A total of 126 men died during the 6-year follow-up. Thresholds for lowest-quartile definitions were 70 ng/dL (to convert to nanomoles per liter, multiply by 0.0347) for bioavailable testosterone, 63.9 ng/mL (to convert to nanomoles per liter, multiply by 0.131) for total IGF-1, and 50 microg/dL (to convert to micromoles per liter, multiply by 0.027) for DHEA-S. Men were divided into 4 groups: no hormone in the lowest quartile (reference) and 1, 2, and 3 hormones in the lowest quartiles. Kaplan-Meier survival and Cox proportional hazards models adjusted for confounders were used in the analysis.
RESULTS
Compared with men with levels of all 3 hormones above the lowest quartiles, having 1, 2, and 3 dysregulated hormones was associated with hazard ratios for mortality of 1.47 (95% confidence interval [CI], 0.88-2.44), 1.85 (95% CI, 1.04-3.30), and 2.29 (95% CI, 1.12-4.68), respectively (test for trend, P <.001). In the fully adjusted analysis, only men with 3 anabolic hormone deficiencies had a significant increase in mortality (hazard ratio, 2.44; 95% CI, 1.09-5.46 (test for trend, P <.001).
CONCLUSIONS
Age-associated decline in anabolic hormone levels is a strong independent predictor of mortality in older men. Having multiple hormonal deficiencies rather than a deficiency in a single anabolic hormone is a robust biomarker of health status in older persons.
Publication
Journal: Journal of Investigative Dermatology
July/15/2003
Abstract
Although the human sebaceous gland can synthesize cholesterol from acetate and can further metabolize steroids such as dehydroepiandrosterone into potent androgens, the de novo production of steroids from cholesterol has not been demonstrated in human skin. The goal of this study was to delineate the steroidogenic pathway upstream from dehydroepiandrosterone by documenting the presence of members of the P450 side chain cleavage system (P450scc). This system catalyzes the initial step in steroid hormone synthesis following translocation of cholesterol to the inner mitochondrial membrane. In concert with its cofactors, adrenodoxin and adrenodoxin reductase, and the transcription factor steroidogenic factor 1, P450scc converts cholesterol to pregnenolone. An SV40 immortalized human sebaceous gland cell line (SEB-1) was established in order to facilitate investigation of the P450scc system. The sebaceous phenotype of SEB-1 sebocytes was confirmed using immunohistochemistry, Oil Red O staining, and gene array expression analysis. Presence of P450scc, adrenodoxin reductase, cytochrome P450 17-hydroxylase (P450c17), and steroidogenic factor 1 was documented in human facial skin, human sebocytes, and SEB-1 sebocytes. Using immunohistochemistry, antibodies to the above proteins localized to epidermis, hair follicles, sebaceous ducts, and sebaceous glands in sections of facial skin. Results of immunohistochemistry were confirmed with Western blotting. Biochemical activity of cytochrome P450scc and P450c17 was demonstrated in SEB-1 sebocytes using radioimmunoassay. The relative abundance of mRNA for P450scc, P450c17, and steroidogenic factor 1 in SEB-1 sebocytes and sebaceous glands was compared to mRNA levels in ovarian theca and granulosa cells using real-time quantitative polymerase chain reaction. Gene array expression analysis and quantitative polymerase chain reaction indicated that mRNA for P450scc is more abundant than mRNA for both P450c17 and steroidogenic factor 1 in sebaceous glands and SEB-1 cells. These data demonstrate that the skin is in fact a steroidogenic tissue. The clinical significance of this finding in mediating androgenic skin disorders such as acne, hirsutism, or androgenetic alopecia remains to be established.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
November/11/1985
Abstract
Twenty-nine patients with polycystic ovary syndrome (PCOS) and 30 normal women had lipoprotein lipid and androgen profiles compared after a 12-h fast. Both PCOS and normal women were evaluated in the proliferative phase of the cycle. PCOS patients had higher serum LH to FSH ratios [2.0 +/- 1.3 (+/- SEM) vs. 0.6 +/- 0.1), higher testosterone (T; 66 +/- 5 vs. 33 +/- 2 ng/ml), higher free T (1.1 +/- 1 vs. 0.4 +/- 0.02 ng/dl), and higher dehydroepiandrosterone sulfate (291 +/- 28 vs. 140 +/- 12 micrograms/dl) levels, and lower T-estrogen-binding globulin-binding capacity (1.5 +/- 0.2 vs. 2.2 +/- 0.1 micrograms/dl) than normal women (all P less than 0.05). The PCOS patients had higher mean serum triglycerides [122 +/- 11 (+/- SEM) 63 +/- 3 mg/dl] and very low density lipoprotein cholesterol levels (24 +/- 2 vs. 13 +/- 1 mg/dl), but lower high density lipoprotein cholesterol levels (43 +/- 2 vs. 58 +/- 2 mg/dl; P less than 0.05). While PCOS patients were heavier and more sedentary and their diets were higher in saturated fat and lower in fiber (P less than 0.01, respectively), the differences in lipoprotein lipid concentrations could not be attributed to body weight. T-estrogen-binding globulin-binding capacity correlated with high density lipoprotein cholesterol in PCOS patients (r = 0.42; P = 0.025) after adjusting for weight. We conclude that hyperandrogenemia in women may result in a male pattern of lipoprotein lipid concentrations. These findings suggest that PCOS patients may have increased atherogenic potential.
Publication
Journal: Clinical Endocrinology
October/15/1997
Abstract
OBJECTIVE
Polycystic ovary syndrome (PCOS) is a common endocrinopathy of unknown aetiology. The aims of this study were to identify whether ovarian thecal cell steroidogenesis is abnormally regulated in PCOS by measuring steroid responses to a single dose of hCG before, and during, suppression of endogenous LH levels by GnRH analogue (GnRHa).
METHODS
Serum levels of LH, FSH, 17 alpha hydroxyprogesterone (17OHP), androstenedione, testosterone and dehydroepiandrosterone sulphate were measured before, and 48 hours after, a single intramuscular injection of 10,000 IU hCG. The test was repeated 4 weeks after suppression of endogenous LH levels by GnRHa.
METHODS
The ovarian responses to hCG were compared in three groups of women. Eleven women had normal ovaries and regular cycles, eight had polycystic ovaries but not clinical features of the syndrome (PCO group) and eight had polycystic ovaries, anovulation and either severe hirsutism or alopecia (PCOS group).
RESULTS
Before GnRHa treatment, LH levels were significantly higher in the PCOS group but hCG stimulated a similar rise in 17OHP in all three groups. Following analogue, LH levels were suppressed in all three groups but the 17OHP responses to hCG were significantly higher in both the PCO and PCOS groups compared with normal controls.
CONCLUSIONS
These findings provide further evidence in favour of an intrinsic abnormality of thecal cell steroidogenesis in the polycystic ovary.
Publication
Journal: Clinical Endocrinology
February/15/2007
Abstract
OBJECTIVE
Cross-sectional data suggest that obesity, particularly central obesity, may be associated with decreased production of sex steroid hormones in men. However, longitudinal hormone data on men in relation to obesity status are limited. Previous studies have not consistently demonstrated whether sex steroids are associated specifically to body mass index or to measures of central obesity. Our objective was to examine the relation of obesity (body mass index>> 30 kg/m2), and of central obesity (waist circumference>> 100 cm or waist to hip ratio>> 0.95) to longitudinal change in sex steroid hormones in men.
METHODS
Prospective follow-up of a population-based sample of men in Boston.
METHODS
Nine hundred forty-two (942) men in the Massachusetts Male Ageing Study with complete anthropometry and hormone data at baseline (1987-1989, ages 40-70) and follow-up (1995-1997).
METHODS
Free and total testosterone (FT and TT), dehydroepiandrosterone sulphate (DHEAS), and sex hormone-binding globulin (SHBG) were assessed using standardized methods. Health behaviours and medical history were obtained by structured interview. Repeated measures regression was used to describe trends in steroid hormones and SHBG in relation to obesity status, adjusting for age, smoking, alcohol, comorbidities, and physical activity.
RESULTS
Obesity was associated with decreased levels of total and free testosterone, and of SHBG at follow-up relative to baseline. For any given baseline concentration of TT, FT or SHBG, follow-up levels were lowest among men who remained obese or who became obese during follow-up. This was true for all three indices of obesity. Central adiposity was associated with lower DHEAS levels at follow-up, while elevated body mass index was not.
CONCLUSIONS
Obesity may predict greater decline in testosterone and SHBG levels with age. Central adiposity may be a more important predictor of decline in DHEAS than is body mass index.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
January/30/2006
Abstract
BACKGROUND
We undertook this study to estimate the prevalence of the various androgen excess disorders using the new criteria suggested for the diagnosis of polycystic ovary syndrome (PCOS).
METHODS
The study was performed at two endocrine departments at the University of Palermo (Palermo, Italy).
METHODS
The records of all patients referred between 1980 and 2004 for evaluation of clinical hyperandrogenism were reevaluated. All past diagnoses were reviewed using the actual diagnostic criteria. To be included in this study, the records of the patients had to present the following available data: clinical evaluation of hyperandrogenism, body weight and height, testosterone (T), free T, dehydroepiandrosterone sulfate, 17-hydroxyprogesterone, progesterone, and pelvic sonography. A total of 1226 consecutive patients were seen during the study period, but only the scores of 950 patients satisfied all criteria and were reassessed for the diagnosis.
RESULTS
The prevalence of androgen excess disorders was: PCOS, 72.1% (classic anovulatory patients, 56.6%; mild ovulatory patients, 15.5%), idiopathic hyperandrogenism, 15.8%; idiopathic hirsutism, 7.6%; 21-hydroxylase-deficient nonclassic adrenal hyperplasia, 4.3%; and androgen-secreting tumors, 0.2%. Compared with other androgen excess disorders, patients with PCOS had increased body weight whereas nonclassic adrenal hyperplasia patients were younger and more hirsute and had higher serum levels of T, free T, and 17-hydroxyprogesterone.
CONCLUSIONS
Classic PCOS is the most common androgen excess disorder. However, mild androgen excess disorders (ovulatory PCOS and idiopathic hyperandrogenism) are also common and, in an endocrine setting, include about 30% of patients with clinical hyperandrogenism.
Publication
Journal: Journal of Biological Chemistry
August/20/2003
Abstract
The mechanism for the cellular extrusion of sulfated conjugates is still unknown. In the present study, we investigated whether human wild type ABCG2 transports estrone 3-sulfate (E1S) using membrane vesicles from cDNA-transfected mouse lymphoma cell line (P388 cells). The uptake of [3H]E1S into ABCG2-expressing membrane vesicles was stimulated by ATP, and the Km value for [3H]E1S was determined to be 16.6 microm. The ABCG2-mediated transport of [3H]E1S was potently inhibited by SN-38 and many sulfate conjugates but not by glucuronide and glutathione conjugates or other anionic compounds. Other sulfate conjugates such as [3H]dehydroepiandrosterone sulfate (DHEAS) and [35S]4-methylumbelliferone sulfate (Km = 12.9 microm) and [35S]6-hydroxy-5,7-dimethyl-2-methylamino-4-(3-pyridylmethyl)benzothiazole (E3040) sulfate (Km = 26.9 microm) were also transported by ABCG2. Although [3H]methotrexate, [3H]17beta-estradiol-17beta-D-glucuronide, [3H]2,4-dinitrophenyl-S-glutathione, and [14C]4-methylumbelliferone glucuronide were transported by ABCG2, this took place to a much lesser extent compared with [3H]E1S. It was suggested that ABCG2 preferentially transports sulfate conjugates and that E1S and DHEAS are the potential physiological substrates for this transporter.
Publication
Journal: Molecular Pharmacology
September/19/1990
Abstract
The human P450III family has been shown to be composed of at least four members, P450IIIA3 (HLp), P450IIIA4 (P450NF), P450IIIA5 (HLp3), and P450IIIA6 (HLp2). Due to the lack of probes that specifically recognize the individual members of this family, little is known about their relative expression. We prepared a form-specific antibody to P450IIIA5 by immunoabsorption of anti-P450IIIA5 IgG against Sepharose 4B upon which microsomes that did not contain P450IIIA5 or purified P450IIIA3 had been bound. Immunoblot analyses demonstrated that P450IIIA5 was expressed at detectable levels in only 19 of 66 (29%) human livers. The expression of P450IIIA5 was not influenced by the gender or medical history of the patients. When the expression of P450IIIA5 in different age groups was examined, it was observed that P450IIIA5 was detected in a statistically significantly higher percentage of children and adolescents (19 years old and under), as compared with the remaining population (8 of 17, 47%, versus 11 of 46, 24%, respectively). Furthermore, P450IIIA5 was detected in 1 of 10 human fetal livers. Of the large number of compounds identified as substrates of P450III family members, P450IIIA5 was found to actively metabolize nifedipine, testosterone, estradiol, dehydroepiandrosterone 3-sulfate, and cortisol, whereas it metabolized poorly or did not metabolize erythromycin, quinidine, 17 alpha-ethynylestradiol, and aflatoxins. The acetylenic steroid gestodene was found to be an effective mechanism-based inhibitor of both P450IIIA4 and P450IIIA5. Immunoblots of microsomes isolated from untreated and dexamethasone-, phenobarbital-, or 3-methylcholanthrene-treated HepG2 cells that were developed with an antibody that recognizes all the P450III family members demonstrated that no proteins in the P450III family were expressed by the HepG2 cells. In conclusion, our studies indicate that P450IIIA5 is polymorphically expressed at all stages of human development and is more limited in its metabolic capabilities than is P450IIIA4.
Publication
Journal: Progress in Neurobiology
January/15/2004
Abstract
Without medical progress, dementing diseases such as Alzheimer's disease will become one of the main causes of disability. Preventing or delaying them has thus become a real challenge for biomedical research. Steroids offer interesting therapeutical opportunities for promoting successful aging because of their pleiotropic effects in the nervous system: they regulate main neurotransmitter systems, promote the viability of neurons, play an important role in myelination and influence cognitive processes, in particular learning and memory. Preclinical research has provided evidence that the normally aging nervous system maintains some capacity for regeneration and that age-dependent changes in the nervous system and cognitive dysfunctions can be reversed to some extent by the administration of steroids. The aging nervous system also remains sensitive to the neuroprotective effects of steroids. In contrast to the large number of studies documenting beneficial effects of steroids on the nervous system in young and aged animals, the results from hormone replacement studies in the elderly are so far not conclusive. There is also little information concerning changes of steroid levels in the aging human brain. As steroids present in nervous tissues originate from the endocrine glands (steroid hormones) and from local synthesis (neurosteroids), changes in blood levels of steroids with age do not necessarily reflect changes in their brain levels. There is indeed strong evidence that neurosteroids are also synthesized in human brain and peripheral nerves. The development of a very sensitive and precise method for the analysis of steroids by gas chromatography/mass spectrometry (GC/MS) offers new possibilities for the study of neurosteroids. The concentrations of a range of neurosteroids have recently been measured in various brain regions of aged Alzheimer's disease patients and aged non-demented controls by GC/MS, providing reference values. In Alzheimer's patients, there was a general trend toward lower levels of neurosteroids in different brain regions, and neurosteroid levels were negatively correlated with two biochemical markers of Alzheimer's disease, the phosphorylated tau protein and the beta-amyloid peptides. The metabolism of dehydroepiandrosterone has also been analyzed for the first time in the aging brain from Alzheimer patients and non-demented controls. The conversion of dehydroepiandrosterone to Delta5-androstene-3beta,17beta-diol and to 7alpha-OH-dehydroepiandrosterone occurred in frontal cortex, hippocampus, amygdala, cerebellum and striatum of both Alzheimer's patients and controls. The formation of these metabolites within distinct brain regions negatively correlated with the density of beta-amyloid deposits.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
June/22/1993
Abstract
To evaluate the effects of obesity on the hypothalamo-pituitary-testicular axis, we compared total and free (FT) testosterone (T), androstenedione, dehydroepiandrosterone and its sulfate, and 5 alpha-androstane-3 alpha, 17 beta-diol glucuronide, and estradiol levels in a group of 35 obese [body mass index (BMI),>> 30] men (aged 17-61 yr) to levels in a nonobese control group. We observed a highly significant negative correlation (P < 0.001) between plasma (F)T levels and BMI and a significant positive correlation (P < 0.01) between E2 levels and BMI. There were no differences between the obese and the nonobese men in levels of androstenedione, dehydroepiandrosterone sulfate, and 5 alpha-androstane-3 alpha, 17 beta-diol glucuronide. Insulin levels were significantly higher in obese men and were significantly (P < 0.02) correlated with the waist hip girth ratio. To evaluate the role of the hypothalamo-pituitary complex in the decreased (F)T levels in obese men, diurnal (0800-2000 h) LH pulsatility was studied in eight obese middle-aged men and eight age-matched controls. The pulsatility of plasma cortisol levels was also studied. Whereas LH pulse frequency was similar in the obese and control subjects, mean diurnal LH levels, mean diurnal LH pulse amplitude, and the sum of all diurnal LH pulse amplitudes and secretory masses were significantly lower in the obese than in the controls. Moreover, there was a highly significant correlation between the sum of LH pulse amplitudes and plasma (F)T levels. This decrease in LH pulse amplitude is not an isolated phenomenon of hypothalamo-pituitary dysfunction in obese men, because the pulse amplitude of plasma cortisol levels was also decreased. The decreased LH pulse amplitude together with the normal respond of Leydig cells to hCG stimulation reported in the literature suggest by inference that the decreased FT levels in obese men are the consequence of a hypogonadotropism. The decreased LH pulse amplitude and the decreased amplitude of cortisol pulses, and hence probably of ACTH pulses, point toward a general alteration of hypothalamo-pituitary function in obese men.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/2/2005
Abstract
The role played by endogenous hormones in many diseases makes it important to understand factors influencing their levels. This study examined the distribution of total and free estradiol, FSH, and dehydroepiandrosterone sulfate (DHEAS) by age and sex and associations of these hormones with body mass index (BMI), lifestyle factors, and chronic diseases. Plasma samples taken from 1555 men and 1952 women 25-84 yr of age in 1994-1995 Tromsø Study were analyzed in 2001. Total estradiol increased with age among men (P < 0.001), with or without adjustment for BMI and lifestyle factors. FSH increased with age both in men (P < 0.001) as well as pre- (P < 0.001) and postmenopausal women (P = 0.01) after similar adjustment, and DHEAS decreased with age in both sexes (P < 0.001). With increasing BMI, free estradiol increased in men (P = 0.004), total and free estradiol increased in postmenopausal women (P < 0.001), and FSH decreased in men (P = 0.03) and postmenopausal women (P < 0.001). Men with chronic diseases had lower levels of DHEAS, compared with healthy men (P < 0.001). Smokers had higher DHEAS levels than nonsmokers. Further studies are needed to confirm these hormonal changes with age and disease.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
August/30/2000
Abstract
The aims of this study were to describe, in relation to date of final menses, the average androgen levels of women in the years before and after this date, and to determine the extent to which these average levels were dependent on age and body mass index (BMI) and the degree of tracking in residual androgen levels, or the extent to which individuals above (below) the mean for their age or time relative to final menstrual period (FMP) and BMI remain above (below) the mean as time progresses. Serial levels of serum sex hormone-binding globulin (SHBG), testosterone (T), and dehydroepiandrosterone sulfate (DHEAS) were measured annually in 172 women from the Melbourne Women's Midlife Health Project who experienced a natural menopause during 7 yr of follow-up. Fasting blood samples were drawn between days 4-8 if women were still menstruating or after 3 months of amenorrhea. The free androgen index (FAI) was calculated as the ratio ofT to SHBG x 100. Means of the log-transformed androgen levels were analyzed as a double logistic function of time relative to FMP as well as age and BMI, and correlations between repeated androgen levels were measured. Mean SHBG levels decreased by 43% from 4 yr before to 2 yr after the FMP. The time of most change was 2 yr before FMP [95% confidence interval (CI), 0.8-3.2]. SHBG levels were, on the average, 5% lower for each halving of estradiol (E2) levels and 4% lower for each kilogram per m2 of BMI (P < 0.0001). About one third of the decline in SHBG was explained by E2 and BMI. After adjusting for all variables, SHBG showed strong tracking. Mean T levels did not vary with time relative to FMP and were independent of age and BMI. Residual values of T showed weak tracking. The FAI increased by 80% from 4 yr before FMP to 2 yr after FMP, and changed maximally 2.2 yr before FMP (95% CI, 1.2-3.2). The FAI was not related to age or E2, but was, on the average, 4% higher for each kilogram per m2 of BMI (P < 0.0001). Residual values of FAI showed moderate tracking. Mean DHEAS levels were not related to the FMP, but were 1.5% lower for each year of age (P < 0.01) and 3.8% lower for each kilogram per m2 of BMI (P < 0.0001). Residual values of DHEAS showed strong tracking. It is concluded that SHBG and FAI levels change at the time of the menopause, at least partially due to the decline in E2. DHEAS decreases as a function of age, not time relative to FMP, and T remains unchanged during the menopausal years. SHBG and DHEAS show a high degree of stability within an individual over time.
Publication
Journal: Progress in Neuro-Psychopharmacology and Biological Psychiatry
May/8/2005
Abstract
The term "neurosteroid" (NS) was introduced by Baulieu in 1981 to name a steroid hormone, dehydroepiandrosterone sulfate (DHEAS), that was found at high levels in the brain long after gonadectomy and adrenalectomy, and shown later to be synthetized by the brain. Later, androstenedione, pregnenolone and their sulfates and lipid derivatives as well as tetrahydrometabolites of progesterone (P) and deoxycorticosterone (DOC) were identified as neurosteroids. The term "neuroactive steroid" (NAS) refers to steroids which, independent of their origin, are capable of modifying neural activities. NASs bind and modulate different types of membrane receptors. The GABA and sigma receptor complexes have been the most extensively studied, while glycine-activated chloride channels, nicotinic acetylcholine receptors, voltage-activated calcium channels, although less explored, are also modulated by NASs. Within the glutamate receptor family, N-methyl-d-aspartate (NMDA) receptors, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors and kainate receptors have also been demonstrated to be a target for steroid modulation. Besides their membrane effects, once inside the neuron oxidation of Ring A reduced pregnanes, THP and THDOC, bind to the progesterone intracellular receptor and regulate gene expression through this path. The involvement of NASs on depression syndromes, anxiety disorders, stress responses to different stress stimuli, memory processes and related phenomena such as long-term potentiation are reviewed and critically evaluated. The importance of context for the interpretation of behavioral effects of hormones as well as for hormonal levels in body fluids is emphasized. Some suggestions for further research are given.
Publication
Journal: Journal of the National Cancer Institute
May/30/1996
Abstract
BACKGROUND
High levels of androgens and estrogens have been reported to be associated with breast cancer. However, the multiplicity of factors that influence hormone levels and methodologic issues complicate the study of the relationship between steroid sex hormones and breast cancer.
OBJECTIVE
Using an improved study design, we assessed prospectively the relationship between the principal steroid sex hormones in serum and the subsequent occurrence of invasive breast cancer in postmenopausal women.
METHODS
Four thousand fifty-three healthy postmenopausal women aged 40-69 years, were enrolled from June 1987 through June 1992 in a prospective investigation of hormones and diet in the etiology of breast tumors (ORDET study) as part of a larger volunteer cohort of 10 788 premenopausal and postmenopausal women from Varese Province, northern Italy. At recruitment, blood samples were taken between 8:00 AM and 9:30 AM (after overnight fasting), and sera were preserved in -80 degree Celsius freezers. Women who had received hormone treatment in the 3 months prior to enrollment, who had bilateral ovariectomy, or who had a history of cancer or liver disease were not recruited. Twenty-five women in the final eligible cohort of postmenopausal women developed histologically confirmed, invasive breast cancer during the first 3.5 years of follow-up for the cohort (13 537 women-years). For each case subject, four control subjects were randomly chosen after matching for factors possibly affecting hormone preservation in serum. One case subject and eight control subjects were excluded because premenopausal hormonal patterns were found; thus, after also excluding the four control subjects matched to the ineligible case subject, we included 24 case and 88 control subjects. In the spring of 1994, stored sera of case and control subjects were assayed in a blinded manner for dehydroepiandrosterone sulfate and estradiol (E2) by in-house radioimmunoassay and for total and free testosterone and sex hormone-binding globulin by commercially available nonextraction iodination kits. Mean differences in risk factors were tested by analysis of variance for paired data. Relative risks (RRs) were estimated by conditional logistic regression analysis. All P values resulted from two-sided tests.
RESULTS
Age-adjusted mean values of total testosterone, free testosterone, and E2 were significantly higher in case subjects than in control subjects: total testosterone, 0.34 ng/mL versus 0.25 ng/mL (P<.001); free testosterone, 1.07 pg/ml versus 0.77 pg/mL (P= .006); and E2, 25 pg/mL versus 22 pg/mL (P= .027). Age-adjusted RRs for breast cancer in increasing tertiles were as follows: for total testosterone, 1.0, 4.8, and 7.0 (P for trend =.026); for free testosterone, 1.0, 1.8, and 5.7 (P for trend=.005); and for total E2, 1.0, 7.1, and 5.5 (P for trend= .128).
CONCLUSIONS
This prospective study provides further evidence in support of the already established association between elevated estrogen levels and breast cancer. Even more importantly, it provides new evidence that high serum testosterone levels precede breast cancer occurrence.
Publication
Journal: JAMA - Journal of the American Medical Association
November/14/2004
Abstract
BACKGROUND
Dehydroepiandrosterone (DHEA) administration has been shown to reduce accumulation of abdominal visceral fat and protect against insulin resistance in laboratory animals, but it is not known whether DHEA decreases abdominal obesity in humans. DHEA is widely available as a dietary supplement without a prescription.
OBJECTIVE
To determine whether DHEA replacement therapy decreases abdominal fat and improves insulin action in elderly persons.
METHODS
Randomized, double-blind, placebo-controlled trial conducted in a US university-based research center from June 2001 to February 2004.
METHODS
Fifty-six elderly persons (28 women and 28 men aged 71 [range, 65-78] years) with age-related decrease in DHEA level.
METHODS
Participants were randomly assigned to receive 50 mg/d of DHEA or matching placebo for 6 months.
METHODS
The primary outcome measures were 6-month change in visceral and subcutaneous abdominal fat measured by magnetic resonance imaging and glucose and insulin responses to an oral glucose tolerance test (OGTT).
RESULTS
Of the 56 men and women enrolled, 52 underwent follow-up evaluations. Compliance with the intervention was 97% in the DHEA group and 95% in the placebo group. Based on intention-to-treat analyses, DHEA therapy compared with placebo induced significant decreases in visceral fat area (-13 cm2 vs +3 cm2, respectively; P = .001) and subcutaneous fat (-13 cm2 vs +2 cm2, P = .003). The insulin area under the curve (AUC) during the OGTT was significantly reduced after 6 months of DHEA therapy compared with placebo (-1119 muU/mL per 2 hours vs +818 muU/mL per 2 hours, P = .007). Despite the lower insulin levels, the glucose AUC was unchanged, resulting in a significant increase in an insulin sensitivity index in response to DHEA compared with placebo (+1.4 vs -0.7, P = .005).
CONCLUSIONS
DHEA replacement could play a role in prevention and treatment of the metabolic syndrome associated with abdominal obesity.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
July/16/1995
Abstract
A distinct human estrogen sulfotransferase (hEST-1) cDNA has been isolated from a human liver lambda Zap cDNA library using a PCR procedure. The enzymatically active protein has been expressed in two bacterial expression systems and the kinetic and immunologic properties of the enzyme have been characterized. The full-length cDNA for hEST-1 is 994 base pairs in length and encodes a 294 amino acid protein with a calculated molecular mass of 35,123 Da. Purified hEST-1 migrated with an apparent molecular mass of 35,000 Da during SDS-polyacrylamide gel electrophoresis. Immunoblot analysis of hEST-1 expressed in E. coli with a rabbit anti-hEST-1 antibody yields a band of approximately 35,000 Da. The anti-hEST-1 antibody also detects a single band in human liver and jejunum cytosol which migrates with the same molecular mass as expressed hEST-1. There was also no cross-reactivity of hEST-1 with rabbit anti-hP-PST or rabbit anti-hDHEA-ST antibodies upon immunoblot analysis. hEST-1 was expressed in bacteria and purified to homogeneity. Expressed hEST-1 activity has a significantly greater affinity for estrogen sulfation than that found for the other human STs which conjugate estrogens. hEST-1 maximally sulfates beta-estradiol and estrone at concentrations of 20 nM. hEST-1 also sulfates dehydroepiandrosterone, pregnenolone, ethinylestradiol, and 1-naphthol, at significantly higher concentrations; however, cortisol, testosterone and dopamine are not sulfated. The results presented in this paper describe the expression and characterization of a human EST distinct from other human STs which sulfate estrogens. The high affinity of hEST-1 for estrogens indicates that this ST may be important in both the metabolism of estrogens and in the regulation of their activities.
Publication
Journal: Diabetes, Obesity and Metabolism
July/19/2004
Abstract
BACKGROUND
Mild hypoandrogenism in men, usually defined by low levels of testosterone, is a peculiar feature of abdominal obesity that independently predicts the development of insulin resistance and diabetes mellitus. Little is known about the short- and long-term effects of weight loss on sex steroids in abdominally obese men, however.
OBJECTIVE
We assessed the effect of rapid weight loss and sustained weight maintenance on the plasma concentrations of testosterone and other sex hormones in 58 abdominally obese men (age, 46.3 +/- 7.5 years; body mass index, 36.1 +/- 3.8 kg/m(2); waist girth, 121 +/- 10 cm) with the metabolic syndrome.
RESULTS
The men lost on average 16.3 +/- 4.5 kg during a 9-week very low-calorie diet (VLCD) and maintained 14.3 +/- 9.1 kg weight loss after a 12-month maintenance period (vs. baseline, p < 0.001). Sex hormone-binding globulin (SHBG) increased from 27.6 +/- 11.9 to 48.1 +/- 23.5 nmol/l during the VLCD but decreased to 32.6 +/- 12.9 nmol/l during weight maintenance, which was still higher than at baseline (p < 0.001). Free testosterone (fT) increased from 185 +/- 66 to 208 +/- 70 pmol/l (p = 0.002) during the VLCD and remained high after 1 year of weight maintenance (212 +/- 84 pmol/l, p = 0.002). Total testosterone levels followed a pattern intermediate between fT and SHBG. Plasma estradiol and dehydroepiandrosterone sulphate concentrations changed only transiently or not at all.
CONCLUSIONS
Rapid weight loss with successful weight maintenance in abdominally obese men with the metabolic syndrome brings about a sustained increase in fT levels. The dramatic increase in SHBG attenuated initially during weight maintenance but remained elevated. These findings may be important with regard to prevention of progressive metabolic decompensation and cardiovascular disease associated with obesity and the metabolic syndrome.
Publication
Journal: Neuroscience
March/11/1998
Abstract
The sigma1 (sigma 1) receptor agonists exert potent anti-amnesic effects, as they apparently block the learning impairments either induced by the muscarinic receptor antagonist scopolamine, the N-methyl-D-aspartate receptor antagonist dizocilpine or inherently due to the age-related deficits in senescence-accelerated mice. We recently described the amnesia induced by the beta-amyloid-related peptide beta 25-35, administered centrally in an aggregated form, in mice. The deficits were sensitive to cholinomimetics or to N-methyl-D-aspartate/glycine modulatory site agonists. Herein, we examined the effects of sigma 1 receptor ligands on the beta 25-35 peptide-induced amnesia. The effects of neuro(active) steroids, which interact in vitro and in vivo with sigma 1 receptors were examined in parallel. Mnesic capacity was evaluated seven days after administration of aggregated beta 25-35 peptide (3 nmol), using spontaneous alternation in the Y-maze for spatial short-term memory, or after 14 days, using the step-down type passive avoidance test for long-term memory. The sigma 1 receptor agonists (+)-pentazocine, PRE-084, or SA4503 attenuated, in a dose-dependent and bell-shaped manner, the beta 25-35 peptide-induced deficits on both tests. These effects were antagonized by haloperidol or BMY-14802, confirming the sigma 1 receptor pharmacology. Pregnenolone, dehydroepiandrosterone, and their sulphate esters, but not progesterone, also dose-dependently attenuated the beta 25-35 peptide-induced deficits. Progesterone blocked the beneficial effects of each other neurosteroid, behaving as an antagonist. Furthermore, haloperidol blocked the effects induced by neurosteroids, whereas progesterone antagonized the effects of the non-steroidal sigma 1 receptor agonists, showing a clear crossed pharmacology of different drug classes. These results demonstrate that: (i) the anti-amnesic effect of sigma 1 receptor agonists may be of therapeutic relevance in pathological states affecting the cholinergic and/or glutamatergic systems, such as in pathological aging; (ii) neurosteroids play an important role in learning processes and may collectively constitute a therapeutic target; (iii) the interaction between sigma 1 systems and neurosteroids appears indeed of behavioural relevance.
Publication
Journal: Journal of the American Society of Nephrology : JASN
April/9/2007
Abstract
Human organic anion transporter 4 (hOAT4) is located at the apical membrane of proximal tubule cells and involved in renal secretion and reabsorption of endogenous substances as well as many drugs and xenobiotics. This study reevaluated the physiologic role, transport mode, and driving forces of hOAT4. 6-Carboxyfluorescein (6-CF) uptake into HEK293 cells that stably expressed hOAT4 was saturable, resulting in a K(m) of 108 muM. 6-CF as well as [(3)H]estrone sulfate ([(3)H]ES) accumulation by HEK293-hOAT4 cells were abolished by ES, dehydroepiandrosterone sulfate, sulfinpyrazone, benzbromarone, and probenecid, whereas several OA, including p-aminohippurate (PAH), lactate, pyrazinoate, nicotinate, glutarate, and the diuretic hydrochlorothiazide (HCTZ) exhibited a slight or a NS inhibitory effect. PAH and glutarate are not taken up by HEK293-hOAT4 cells, but they trans-stimulated 6-CF and [(3)H]ES uptake, indicating an asymmetric interaction of hOAT4 with these substrates. In chloride-free medium, HEK293-hOAT4-mediated [(3)H]PAH efflux was almost abolished, whereas addition of ES restored it comparable to Ringer solution, consistent with a physiologic ES/PAH or PAH/Cl(-) exchange mode of hOAT4. Moreover, an acidification of the uptake medium increased 6-CF as well as [(3)H]ES uptake, which was reduced by nigericin, suggesting that hOAT4 also can operate as an OA/OH(-) exchanger. hOAT4 facilitates substantial uptake of [(14)C]urate, which was elevated 2.6-fold by intracellular HCTZ. Thus, hOAT4 is the long-postulated, low-affinity apical urate anion exchanger that facilitates HCTZ-associated hyperuricemia.
Publication
Journal: Journal of Psychosomatic Research
February/18/2004
Abstract
OBJECTIVE
The purpose of this study was to investigate the immune, endocrine, and metabolic correlates of burnout among women.
METHODS
Forty-three participants with high and 20 participants with low scores for the Shirom-Melamed Burnout Questionnaire were compared in terms of subjective symptoms, job strain, social support, plasma levels of prolactin, tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta), C-reactive protein (CRP), neopterin, serum levels of dehydroepiandrosterone sulphate (DHEAs), progesterone, estradiol, cortisol, and glycated hemoglobin (HbA1C) in whole blood.
RESULTS
Besides reporting more job strain, less social support at work, and higher levels of anxiety, depression, vital exhaustion (VE), and sleep impairments, participants with high burnout manifested higher levels of TNF-alpha and HbA1C, independent of confounders including depression.
CONCLUSIONS
Among women, burnout seems to involve enhanced inflammatory responses and oxidative stress.
Publication
Journal: The Lancet
July/4/1994
Abstract
Dehydroepiandrosterone (DHEA), with its sulphate conjugate (DHEAS), is the most abundant steroid hormone in the circulation but its physiological importance is unclear. We propose that DHEA has either oestrogen-like or androgen-like effects depending on the hormonal milieu. In premenopausal women DHEA is either an oestrogen antagonist, perhaps through the competitive binding of its metabolite 5-androstene-3 beta, 17 beta-diol (ADIOL) and oestradiol to the oestrogen receptor, or an androgen through its metabolism to androstenedione and testosterone. In women DHEA contributes to abdominal obesity and insulin resistance: in the premenopausal high oestrogen concentrations may counterbalance the androgenic effects of DHEA but in the postmenopausal metabolism to testosterone may increase the risk of cardiovascular disease, though this effect may be counterbalanced by the age-dependent decline in DHEA and also by the oestradiol-like effects of ADIOL. In some breast cancer cell lines in a low oestrogen milieu DHEA has an oestradiol-like effect, stimulating tumour growth, whereas in oestradiol abundance DHEA antagonises the growth-stimulating effect of oestradiol. In men, with an androgenic milieu, DHEA acts like an oestrogen and protects against cardiovascular disease.
Publication
Journal: Reproductive Biology and Endocrinology
October/9/2011
Abstract
BACKGROUND
With infertility populations in the developed world rapidly aging, treatment of diminished ovarian reserve (DOR) assumes increasing clinical importance. Dehydroepiandrosterone (DHEA) has been reported to improve pregnancy chances with DOR, and is now utilized by approximately one third of all IVF centers world-wide. Increasing DHEA utilization and publication of a first prospectively randomized trial now warrants a systematic review.
METHODS
PubMed, Cochrane and Ovid Medline were searched between 1995 and 2010 under the following strategy: [> and>]. Bibliographies of relevant publications were further explored for additional relevant citations. Since only one randomized study has been published, publications, independent of evidence levels and quality assessment, were reviewed.
RESULTS
Current best available evidence suggests that DHEA improves ovarian function, increases pregnancy chances and, by reducing aneuploidy, lowers miscarriage rates. DHEA over time also appears to objectively improve ovarian reserve. Recent animal data support androgens in promoting preantral follicle growth and reduction in follicle atresia.
CONCLUSIONS
Improvement of oocyte/embryo quality with DHEA supplementation potentially suggests a new concept of ovarian aging, where ovarian environments, but not oocytes themselves, age. DHEA may, thus, represent a first agent beneficially affecting aging ovarian environments. Others can be expected to follow.
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Publication
Journal: Journal of Clinical Endocrinology and Metabolism
December/1/2005
Abstract
BACKGROUND
The relationship of reproductive hormones to vasomotor symptoms (VMS) has been incompletely explored, although an increase in such symptoms at midlife and their reduction with hormone therapy suggest a strong and direct relationship. Vasomotor symptoms are reported by 65-76% of women traversing the menopausal transition and are a primary reason for medical intervention during this life stage.
OBJECTIVE
The purpose of this report was to relate longitudinal serum concentrations of the reproductive hormones estradiol (E2), FSH, testosterone (T), dehydroepiandrosterone sulfate (DHEAS), and SHBG and the free hormone indices free E2 index (FEI) and free T index (FTI) with the occurrence of VMS in women traversing the menopausal transition.
METHODS
The Study of Women's Health Across the Nation is a multisite, longitudinal, cohort study of the menopausal transition being conducted in community-based groups of women.
METHODS
At baseline, 3302 menstruating women who belonged to one of five ethnic/racial groups were recruited and followed up with annual visits. Frequencies of symptoms (hot flashes, night sweats) for the prior 2 wk and measures of other covariates as well as potentially confounding variables were self-reported in the annual interview. Serum was obtained annually, on d 2-5 of a spontaneous cycle in cycling women or within 90 d of the anniversary of the baseline study visit in noncycling women and assayed for FSH, E2, T, SHBG, and DHEAS. FTI and FEI were calculated. This analysis incorporated available longitudinal data from 3293 women, excluding information collected at or after first report of hormone therapy use or hysterectomy. Data were analyzed using longitudinal marginal logistic regression models and a partial proportional odds model.
RESULTS
After adjusting for age, body mass index, and other related covariates, VMS prevalence increased with higher (log)FSH concentrations, and the increase was greater when blood was drawn more than 5 d after menses began. FSH concentrations were positively associated with the frequency of either hot flashes or night sweats, and higher FSH concentrations were associated with greater odds of reporting more frequent symptoms. Vasomotor symptom prevalence decreased with higher (log)E2, (sqrt)SHBG, and (log)FEI but only when these hormone values were modeled independently of (log)FSH values and the specimens were obtained outside the d 2-5 window. When modeled simultaneously with (log)FSH, (log)E2, (sqrt)SHBG, and (log)FEI were no longer significantly associated with symptom prevalence. (Cubic root)T and (sqrt)DHEAS concentrations and (log)FTI were not associated with the prevalence of VMS.
CONCLUSIONS
Annual serum FSH concentrations, but not E2, T, DHEAS, FTI, or FEI when collectively modeled longitudinally, are associated with both the prevalence and frequency of VMS in women at midlife.
Publication
Journal: Journal of Lipid Research
February/16/2004
Abstract
Cholesterol sulfate is quantitatively the most important known sterol sulfate in human plasma, where it is present in a concentration that overlaps that of the other abundant circulating steroid sulfate, dehydroepiandrosterone (DHEA) sulfate. Although these sulfolipids have similar production and metabolic clearance rates, they arise from distinct sources and are metabolized by different pathways. While the function of DHEA sulfate remains an enigma, cholesterol sulfate has emerged as an important regulatory molecule. Cholesterol sulfate is a component of cell membranes where it has a stabilizing role, e.g., protecting erythrocytes from osmotic lysis and regulating sperm capacitation. It is present in platelet membranes where it supports platelet adhesion. Cholesterol sulfate can regulate the activity of serine proteases, e.g., those involved in blood clotting, fibrinolysis, and epidermal cell adhesion. As a result of its ability to regulate the activity of selective protein kinase C isoforms and modulate the specificity of phosphatidylinositol 3-kinase, cholesterol sulfate is involved in signal transduction. Cholesterol sulfate functions in keratinocyte differentiation, inducing genes that encode for key components involved in development of the barrier. The accumulating evidence demonstrating a regulatory function for cholesterol sulfate appears solid; the challenge now is to work out the molecular mechanisms whereby this interesting molecule carries out its various roles.
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