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Publication
Journal: Human Reproduction
September/25/2013
Abstract
OBJECTIVE
Is diminished functional ovarian reserve (DFOR) associated with low androgen levels?
CONCLUSIONS
Low androgen levels are associated with DFOR at all ages.
BACKGROUND
Androgen supplementation via dehydroepiandrosterone (DHEA) has been reported to improve functional ovarian reserve (FOR); pregnancy rates in IVF cycles are associated with how well DHEA converts to testosterone (T); and androgen effects through the androgen receptor have been demonstrated in mice to beneficially affect early stages of follicle maturation.
METHODS
In a controlled cohort study we investigated consecutive women presenting to our center with two forms of DFOR, premature ovarian aging/occult primary ovarian insufficiency (POA/OPOI) and physiologic diminished ovarian reserve (DOR). As controls for POA/OPOI patients, infertile women with normal age-specific FOR were recruited.
METHODS
The study involved 140 women with POA/OPOI, defined as age <38 years and abnormally low FOR by age-specific FSH and/or anti-Müllerian hormone (AMH), 166 women with DOR, defined as women age >40 years. Forty-nine control patients <38 years demonstrated normal FOR by FSH and/or AMH. In all three patient groups dehydroepiandrosterone (DHEA), DHEA-sulfate (DHEAS), total testosterone (TT) and free testosterone (FT) at the time of initial presentation to our fertility center were assessed. In a small subgroup of women early morning cortisol levels were also assessed.
RESULTS
DHEAS marginally varied between the three groups (P = 0.04), with older women with DOR actually demonstrating higher levels than controls (P = 0.03). TT differed between the three groups more profoundly (P = 0.005), with women with POA/OPOI demonstrating significantly lower levels than controls (P = 0.009). Adjustment for body mass index, age and race in principle maintained observed differences in TT between groups, while adjustment for FMR1 (fragile X mental retardation 1) genotypes/sub-genotypes eliminated all differences. All three patient groups demonstrated low morning cortisol levels.
CONCLUSIONS
While results support lower androgen levels in women with DOR, and even more so in women with POA/OPOI, presented data should be viewed as preliminary, considering the known variability of androgen levels and the small number of women in whom morning cortisol levels were available.
CONCLUSIONS
Especially at young ages DFOR appears associated with significant hypoandrogenism (low T) in comparison with young control patients with normal FOR, raising the question whether this hypoandrogenism originates in adrenals or ovaries. POA/OPOI, thus, phenotypically mimics the polycystic ovary syndrome, where similar questions arise, though in regard to hyperandrogenism.
BACKGROUND
This research was supported by the Foundation for Reproductive Medicine, a not-for-profit medical research foundation and intramural funds from the Center for Human Reproduction. N.G. and D.H.B are members of the Board of the Foundation for Reproductive Medicine. N.G., A.W. and D.H.B. received research support, lecture fees and travel support from a variety of pharmaceutical and medical device companies, none in any way related to the issues discussed in this manuscript. N.G. and D.H.B. are listed as co-inventors on two, already granted US user patents, which claim therapeutic benefits from DHEA supplementation in women with DFOR and DOR: both authors are also listed on additional pending patents in regard to DHEA supplementation and on pending patents, claiming diagnostic and therapeutic benefits from the determination of CGG repeats on the FMR1 gene. N.G. is the owner of the Center for Human Reproduction, where this research was performed.
Publication
Journal: Hormone research
October/24/2001
Abstract
OBJECTIVE
Most patients with polycystic ovary syndrome (PCOS) are obese and known to have insulin resistance. Obesity per se is a cause of insulin resistance. This study was performed to determine whether insulin resistance occurs in patients with PCOS in the absence of obesity and acanthosis nigricans.
METHODS
For this purpose, an euglycemic hyperinsulinemic clamp study was performed in 12 nonobese patients with PCOS and in 10 healthy control subjects matched for age and weight.
RESULTS
The mean serum testosterone and luteinizing hormone (LH) levels were significantly elevated (4.09 +/- 1.32 vs. 1.18 +/- 0.53 pg/ml, p < 0.001, and 11.63 +/- 5.37 vs. 4.98 +/- 2.73 mIU/ml, p < 0.001, respectively), and the serum sex hormone binding globulin level was significantly reduced (40.96 +/- 14.94 vs. 73.98 +/- 30.40 nmol/l, p < 0.001) in patients with PCOS as compared with the values in control subjects. The mean serum insulin level was also elevated in patients with PCOS as compared with control subjects (32.33 +/- 4.98 vs. 19.56 +/- 2.21 microU/ml, p < 0.05). The insulin sensitivity was lower in patients with PCOS as compared with the control subjects (200 +/- 27.8 vs. 427.8 +/- 88.9 micromol x kg(-1) x min(-1), p < 0.001). In patients with PCOS, the serum levels of free testosterone (r = -0.89, p < 0.001) and LH were inversely correlated with the insulin sensitivity (r = -0.63, p < 0.05). Serum follicle-stimulating hormone, prolactin, and dehydroepiandrosterone sulfate levels were similar in both groups.
CONCLUSIONS
These results indicate that a significant degree of insulin resistance exists in nonobese patients with PCOS and that this insulin resistance is significantly related to serum LH and free testosterone levels. Thus, measures to decrease insulin resistance may have to be considered earlier to decrease the potential risks of developing diabetes mellitus and coronary artery disease at later ages of life in these patients.
Publication
Journal: Aging Cell
February/2/2006
Abstract
The detrimental effect of stress on the immune response increases with age, though the mechanisms responsible are not fully understood. The physiological response to stress is regulated in part by the adrenocortical system. Adrenal hormones dehydroepiandrosterone sulphate (DHEAS) and cortisol have opposing effects on the innate immune system, DHEAS enhances while cortisol suppresses immunity and the molar ratio of cortisol to DHEAS increases with age. We found that elderly hip fracture patients produced a robust neutrophilia after injury, but circulating neutrophils showed an impaired antibacterial response. We therefore proposed that adrenocortical hormones mediate the heightened immunosuppression seen in the elderly after injury. We examined neutrophil function and adrenocortical hormone levels in elderly >> 65 years) hip fracture patients and age-matched healthy controls. Thirteen out of 35 elderly patients acquired infections following hip fracture. Neutrophil superoxide production was lower in elderly hip fracture patients compared with controls (P < 0.005) and lower in patients who acquired infection following injury compared with those who did not (P < 0.05). Serum cortisol:DHEAS ratio was higher in elderly hip fracture patients (0.56 +/- 0.38) compared with either age-matched controls (0.36 +/- 0.21; P < 0.05) or young fracture patients (0.087 +/- 0.033; P < 0.0001). Moreover, cortisol: DHEAS was increased in elderly patients who succumbed to infection compared with those who did not (0.803 +/- 0.42 vs. 0.467 +/- 0.28; P < 0.02). In vitro cortisol significantly decreased neutrophil superoxide generation (P < 0.05) and this was prevented by coincubation with DHEAS. We propose that increased cortisol:DHEAS ratios may contribute to reduced immunity following physical stress in the elderly.
Publication
Journal: Social Science and Medicine
August/11/2003
Abstract
Adverse work characteristics and poor social support have been associated with an increased risk for cardiovascular disease and other adverse health outcomes in otherwise apparently healthy adults. We undertook a cross-sectional study to evaluate the relationship between objective health status and work characteristics in industrial workers in Germany. Volunteers (n=324) were recruited from a representative random sample (n=537) of employees of an airplane manufacturing plant. Psychosocial work characteristics were assessed by the 52-item, 13-subscale salutogenetic subjective work analysis (SALSA) questionnaire, which assesses potentially salutogenic and pathogenic conditions. Factor analysis revealed three factors: decision latitude, job demands and social support. Biological health status was determined by the revised allostatic load score with 14 components: body-mass index, waist-to-hip ratio; systolic and diastolic blood pressure; plasma levels of C-reactive protein (CRP), tumor-necrosis factor-alpha, HDL, cholesterol, dehydroepiandrosterone sulfate; glycosylated hemoglobin; urinary cortisol, epinephrine, norepinephrine, and albumin. Score points were given for values in the high-risk quartile (maximum=14). General linear models revealed that older individuals and men had significantly higher allostatic load scores than younger participants or women. Of the SALSA factors, only job demands related significantly to allostatic load. The effect of demands was stronger in older individuals. Post-hoc analysis showed possible positive associations between high job demands and blood pressure or CRP, and between low social support and nocturnal excretion of cortisol or plasma levels of CRP. We conclude that this cross-sectional study on industrial employees found a weak association between a health summary score based on objective medical data and self-reported adverse work characteristics.
Publication
Journal: Breast Cancer Research
March/29/2015
Abstract
BACKGROUND
Prior research supports an association between endogenous sex steroids and breast cancer among postmenopausal women; the association is less clear among premenopausal women.
METHODS
We evaluated the associations between estrogens, androgens, progesterone and sex hormone binding globulin (SHBG) and breast cancer in a nested case-control study in the Nurses' Health Study II. Between 1996 and 1999, 29,611 participants provided blood samples; 18,521 provided samples timed in early follicular and mid-luteal phases of the menstrual cycle. A total of 634 women, premenopausal at blood collection, developed breast cancer between 1999 and 2009 and were matched to 1,264 controls (514 cases and 1,030 controls with timed samples). We used conditional logistic regression controlling for breast cancer risk factors for overall analyses; unconditional logistic regression additionally controlling for matching factors was used for subgroup analyses.
RESULTS
In analyses of premenopausal estrogens including breast cancers diagnosed both before and after menopause, there was no association between follicular estradiol, estrone and free estradiol and risk of either total or invasive breast cancer. Luteal estradiol was positively associated with estrogen receptor positive (ER+)/progesterone receptor positive (PR+) cancers (5th vs. 1st quintile odds ratio (OR): 1.7 (95% confidence interval (CI): 1.0 to 2.9), Ptrend = 0.02). Luteal estrone, free estradiol and progesterone were not associated with risk. Androgens were suggestively or significantly associated with risk when the sample was restricted to invasive tumors (for example, testosterone: OR: 1.4 (1.0 to 2.0), Ptrend = 0.23) and ER+/PR+ disease (testosterone: OR: 1.7 (1.1 to 2.6) Ptrend = 0.10; dehydroepiandrosterone sulfate (DHEAS) OR: 1.3 (0.8 to 2.0) Ptrend = 0.05). SHBG was not associated with breast cancer risk. The results varied by menopausal status at diagnosis, with follicular estradiol suggestively positively associated with breast cancers in women premenopausal at diagnosis (OR: 1.1 (0.9 to 1.3) and significantly inversely associated with postmenopausal disease (OR: 0.6 (0.4 to 0.9); Pheterogeneity < 0.01).
CONCLUSIONS
Androgens were associated with modestly increased risk of breast cancer in this population, with stronger associations for invasive and ER+/PR+ disease. Luteal phase estradiol levels were suggestively associated with ER+/PR+ tumors but no other strong associations were observed with estrogens. Associations with follicular phase estrogens may vary by menopausal status at diagnosis, but case numbers were limited. Additional studies to confirm the role of premenopausal hormones in the etiology of both premenopausal and postmenopausal breast cancer are needed.
Publication
Journal: Journal of Nervous and Mental Disease
March/6/2008
Abstract
Research has suggested that exposure to traumatic events can result in adverse health outcomes. However, the reasons for this are unclear. We examined psychobiologic factors associated with disease mortality among a community-based sample of 4462 male veterans 30 years after military service, including posttraumatic stress disorder (PTSD), erythrocyte sedimentation rate (ESR), white blood cell (WBC) count, and cortisol/dehydroepiandrosterone-sulfate (cortisol/DHEA-s) ratio. In the study, 56% (n = 2490) were theater veterans who served in Vietnam and 44% (n = 1972) era veterans who served elsewhere. During baseline in 1985, 10.2% of theater and 3.4% of era veterans had current PTSD. At follow-up in 2000, 13.6% of men with current baseline PTSD were deceased, compared with 5% without PTSD. Analyses suggested that having PTSD, a high ESR, a high WBC count, and a high cortisol/DHEA-s ratio at baseline were associated with all-cause disease mortality at follow-up. With the exception of cortisol/DHEA-s ratio, these factors also predicted cardiovascular mortality. Depression was not consistently associated with mortality, once other factors were controlled. Noteworthy was that having PTSD had an impact on mortality nearly comparable to common indicators of disease in medicine, such as an ESR >65 mm/h and a WBC count >11,000 mm(3). This study suggests that the morbidity associated with PTSD may be comparable to laboratory measures of disease pathology in common use and warrants further investigation and surveillance among at risk populations.
Publication
Journal: American Journal of Obstetrics and Gynecology
September/25/1975
Abstract
Serum gonadotropin, estrogen, and androgen levels were measured in samples obtained from 19 patients with polycystic ovarian disease (PCO) and from 10 normal women on day 2 to 4 of their menstrual cycles. In patients with PCO, the mean (plus or minus S.E.) concentration was significantly higher (P smaller than 0.001) than the concentrations found in the normal subjects for LH (35 plus or minus 4.6 vs. 12.7 plus or minus 2.6 m.I.U. per milliliter), but not for FSH (10.3 plus or minus 0.7 vs. 8.7 plus or minus 0.9 m.I.U. per milliliter). Estrone (E1) levels (92 plus or minus 4 vs. 52 plus or minus 5 pg. per milliliter) were also significantly higher (P smaller than 0.001), while estradiol (E2) concentrations (58 plus or minus 4 vs. 63 plus or minus 8 pg. per milliliter) were comparable. Testosterone (T) (468 plus or minus 41 vs. 325 plus or minus 34 pg. per milliliter, P smaller than 0.05), androstenedione (delta) (2,083 plus or minus 138 vs. 1,123 plus or minus 153 pg. per milliliter, P smaller than 0.001), and dehydroepiandrosterone sulfate (3.4 plus or minus 0.4 vs. 2.0 plus or minus 0.37 mug per milliliter, P smaller 0.02) were also significantly increased over the values in normal controls. The mean dehydroepiandrosterone (DHEA) was elevated in the patients with PCO (11.3 plus or minus 1.7 vs. 7.5 plus or minus 1.2 mug per milliliter), but was not significantly different. A positive correlation was found between LH levels and both E2 and E1 concentrations in the patients with PCO. These data show a distinct profile of gonadotropin, estrogen, and androgen levels in patients with PCO.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
November/14/2000
Abstract
Precocious pubarche in girls is often preceded by low weight at birth and followed by hirsutism, ovarian hyperandrogenism, and oligomenorrhea in adolescence, the latter usually being accompanied by dyslipidemia and hyperinsulinism, which are, in turn, two major risk factors for cardiovascular disease in later life. We hypothesized that insulin resistance may be a key pathogenetic factor in this sequence. We tested the hypothesis by assessing the effects of an insulin-sensitizing agent, metformin, given at a daily dose of 1275 mg for 6 months to 10 nonobese adolescent girls (mean age, 16.8 yr; body mass index, 21.9 kg/m2; birth weight, 2.7 kg) with hirsutism, ovarian hyperandrogenism (diagnosis by GnRH agonist test), oligomenorrhea, dyslipidemia, and hyperinsulinemia after precocious pubarche. Before the metformin trial, longitudinal studies in these girls had shown that hyperinsulinism was present at prepubertal diagnosis of precocious pubarche, and that it increased markedly in late puberty or early postmenarche. Metformin treatment was well tolerated and was accompanied by a marked drop in hirsutism score, insulin response to oral glucose tolerance test, free androgen index, and baseline testosterone, androstenedione, dehydroepiandrosterone, and dehydroepiandrosterone sulfate levels (all P < 0.01). During metformin treatment, the LH and 17-hydroxyprogesterone hyperresponses to GnRH agonist were attenuated (P < 0.01); serum triglyceride, total cholesterol, and low density lipoprotein cholesterol levels decreased; and high density lipoprotein cholesterol rose. All girls reported regular menses within 4 months. Withdrawal of metformin treatment was followed, within 3 months, by a consistent reversal toward pretreatment conditions. In conclusion, metformin treatment reduced hyperinsulinemia, hirsutism, and hyperandrogenism; attenuated the LH and 17-hydroxyprogesterone hyperresponses to GnRH agonist; improved the atherogenic lipid profile; and restored eumenorrhea in nonobese adolescent girls with a history of precocious pubarche. These observations corroborate the idea that insulin resistance may indeed be a prime factor underpinning the sequence from reduced fetal growth, through precocious pubarche, to adolescent endocrinopathies that are reminiscent of so-called polycystic ovary syndrome.
Publication
Journal: Contraception
April/30/2003
Abstract
In a double-blind, controlled, randomized, four-arm, bicentric clinical study, the effect of four oral contraceptives (OCs) on various hormone parameters and serum-binding globulins was investigated. Four groups with 25 volunteers each (18-35 years of age) were treated for six cycles with monophasic combinations containing 21 tablets with either 30 microg ethinylestradiol (EE) + 2 mg dienogest (DNG) (30EE/DNG), 20 microg EE + 2 mg DNG (20EE/DNG), 10 microg EE + 2 mg estradiol valerate (EV) + 2 mg DNG (EE/EV/DNG) or 20 microg EE + 100 microg levonorgestrel (LNG) (EE/LNG). The study was completed by 91 subjects. Blood samples were taken after at least 12 h of fasting on Day 21-26 of the preceding control cycle and on Day 18-21 of the first, third and sixth treatment cycle. The serum concentrations of free testosterone were significantly decreased by about 40-60% in all four groups, while those of dehydroepiandrosterone sulfate (DHEAS) showed a time-dependent decrease during treatment. Except for EE/EV/DNG, which increased prolactin significantly during the third and sixth cycles, no change was observed with the EE-containing preparations. There was a significant increase in the levels of serum-binding globulins during treatment, which differed according to the composition of the OCs used. The rise in sex hormone-binding globulin (SHBG) was highest during intake of 30EE/DNG (+320%) and lowest with EE/LNG (+80%), while the effect of 20EE/DNG and EE/EV/DNG was similar (+270%). The thyroxine-binding globulin (TBG) levels increased significantly, by 50-60%, during treatment with the DNG-containing formulations, while the effect of EE/LNG was less significant (+30%). The rise in corticosteroid-binding globulin (CBG), which occurred in all groups, was most pronounced in women treated with 30EE/DNG (+90%) and least with EE/EV/DNG (+55%), indicating a strong influence of EE and no effect of the progestogen component. In all treatment groups, the frequency of intracyclic bleeding rose in the first treatment cycle and decreased thereafter. Cycle control was significantly better with 30EE/DNG or EE/LNG than with 20EE/DNG or EE/EV/DNG. There was no significant change in blood pressure, body mass index or pulse rate throughout the study. In conclusion, the DNG-containing OCs caused a higher rise in SHBG and TBG levels than the LNG-containing preparation. The effects on CBG suggest a lesser hepatic effect of 2 mg EV as compared to 20 or 30 microg EE. In contrast to EE, the use of estradiol in OCs appeared to increase prolactin release, while the cycle control was better with the OC containing 30 microg EE.
Publication
Journal: Arthritis and rheumatism
December/17/2002
Abstract
OBJECTIVE
To evaluate the efficacy and tolerability of dehydroepiandrosterone (DHEA) at a dosage of 200 mg/day in adult women with active systemic lupus erythematosus (SLE).
METHODS
In a multicenter randomized, double-blind, placebo-controlled trial, 120 adult women with active SLE received oral DHEA (200 mg/day; n = 61) or placebo (n = 59) for 24 weeks. The primary end point was the mean change from baseline in the Systemic Lupus Activity Measure (SLAM) score at 24 weeks of therapy. Secondary end points included time to first flare, change in SLE Disease Activity Index (SLEDAI) score, and physician's and patient's global assessment scores at week 24.
RESULTS
The two groups were well balanced for baseline characteristics. Mean reductions in SLAM scores from baseline were similar and were not statistically significantly different between treatment groups (DHEA -2.6 +/- 3.4 versus placebo -2.0 +/- 3.8, mean +/- SD). The number of patients with flares was decreased by 16% in the DHEA group (18.3% of DHEA-treated patients versus 33.9% of placebo-treated patients; P = 0.044, based on time to first flare). The mean change in the patient's global assessment was statistically significant between the two groups (DHEA -5.5 versus placebo 5.4; P = 0.005). The number of patients with serious adverse events, most of which were related to SLE flare, was significantly lower in DHEA-treated patients compared with placebo-treated patients (P = 0.010). Expected hormonal effects, including increased testosterone levels and increased incidence of acne, were observed. No life-threatening reactions or serious safety issues were identified during this study.
CONCLUSIONS
The overall results confirm that DHEA treatment was well-tolerated, significantly reduced the number of SLE flares, and improved patient's global assessment of disease activity.
Publication
Journal: Neuroscience
January/23/1992
Abstract
Recently we demonstrated that [3H]dehydroepiandrosterone sulfate binds specifically to two populations of sites in rat brain membranes [Majewska et al. (1990) Eur. J. Pharmac. 189, 307-315]. As an extension of this work, we studied the biochemical and pharmacological properties of [3H]dehydroepiandrosterone sulfate binding to brain membranes and the effects of dehydroepiandrosterone sulfate on GABA-induced currents in cultured neurons. [3H]Dehydroepiandrosterone sulfate binding depended upon incubation time, pH, protein concentration, and incubation temperature. Thermal denaturation or pretreatment of the membranes with protease or phospholipase A2 reduced the binding by 54-85%. The higher affinity [3H]dehydroepiandrosterone sulfate binding sites appeared to be associated with protein and with the GABAA receptor complex. Among substances known to interact with the GABAA receptor complex, pregnenolone sulfate, pentobarbital, and phenobarbital inhibited the binding of [3H]dehydroepiandrosterone sulfate. High micromolar concentrations of dehydroepiandrosterone sulfate inhibited [3H]muscimol and [3H]flunitrazepam binding to rat brain membranes, primarily by reducing the binding affinities. Dehydroepiandrosterone sulfate also produced a concentration-dependent block of GABA-induced currents in cultured neurons from ventral mesencephalon (IC50 = 13 +/- 3 microM). The results of this study are consistent with an action of dehydroepiandrosterone sulfate as a negative noncompetitive modulator of the GABAA receptor. Because concentrations of dehydroepiandrosterone sulfate in the brain undergo physiological variations, this neurosteroid may play a vital role in regulation of neuronal excitability in the central nervous system.
Publication
Journal: Journal of steroid biochemistry
December/10/1986
Abstract
Sex steroids and 5-en-3 beta-hydroxysteroids were determined by radioimmunoassay in specific regions of the human brain, in the anterior and posterior pituitary, in one sensory organ, the retina and in the cranial nerves. Progesterone, androstenedione, testosterone and estrone were found in all areas of the brain and in all the cranial nerves but not in all cases. There was no sex difference except in the case of androstenedione where values were higher in women in some brain areas. Estrone values were always higher than those of estradiol in both men and women. No 5 alpha-dihydrotestosterone was detected in any of the samples studied. The values for pregnenolone, dehydroepiandrosterone and their sulfates were much higher than those of the sex steroids in all areas of the brain and in all the cranial nerves. Values for pregnenolone were greater than those of its sulfate while those of dehydroepiandrosterone were in general equal to or higher than those of its sulfate. The values for pregnenolone were greater than those of dehydroepiandrosterone. There were no obvious regional differences in the concentrations of the 5-en-3 beta-hydroxysteroids either in specific areas of the brain or in the cranial nerves. But there was a definite trend for the free dehydroepiandrosterone values to be higher in women. The possible significance of these observations is discussed.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
January/22/2007
Abstract
Sulfation is an important Phase II conjugation reaction involved in the synthesis and metabolism of steroids in humans. Two different isoforms (2B1a and 2B1b) are encoded by the sulfotransferase (SULT) 2B1 gene utilizing different start sites of transcription resulting in the incorporation of different first exons. SULT2B1a and SULT2B1b are 350 and 365 amino acids in length, respectively, and the last 342 aa are identical. Message for both SULT2B1 isoforms is present in human tissues although SULT2B1b message is generally more abundant. However, to date only SULT2B1b protein has been detected in human tissues or cell lines. SULT2B1b is localized in the cytosol and/or nuclei of human cells. A unique 3'-extension of SULT2B1b is required for nuclear localization in human BeWo placental choriocarcinoma cells. Nuclear localization is stimulated by forskolin treatment in BeWo cells and serine phosphorylation has been identified in the 3'-extension. SULT2B1b is selective for the sulfation of 3beta-hydroxysteroids such as dehydroepiandrosterone and pregnenolone, and may also have a role in cholesterol sulfation in human skin. The substrate specificity, nuclear localization, and tissue localization of SULT2B1b suggest a role in regulating the responsiveness of cells to adrenal androgens via their direct inactivation or by preventing their conversion to more potent androgens and estrogens.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
September/6/1995
Abstract
To clarify the possible action of adrenal androgen on bone cell, the existence, characteristics and regulation of aromatase in human osteoblast-like osteosarcoma cells (HOS) and primary cultured osteoblast-like cells from normal human bones (HO) were examined in this study. Significant positive correlation between bone mineral density (BMD) and serum dehydroepiandrosterone sulfate (DHEA-S) was found in 120 postmenopausal women (51-99 years old) but no correlation was seen between BMD and serum estradiol (E2). In subset analysis, strongly positive correlation of serum DHEA-S and estrone (E1) with BMD was observed in postmenopausal women aged less than 69 years old. Administration of DHEA to ovariectomized rat significantly increased BMD and decreased relative osteoid volume in femur. These in vivo findings strongly suggested that serum adrenal androgen may be converted to estrogen in peripheral organ, especially, osteoblast and be important steroids to maintain BMD. [3H]DHEA was converted to [3H]androstenedione and [3H]androstenedione to [3H]estrone in primary cultured human osteoblast. Osteoblast-like cells showed aromatase activity, and an apparent Km and the Vmax were 4.74 +/- 0.78 nM (mean +/- SD, n = 3) and 0.83 +/- 0.79 fmol/mg protein/h for HOS, and 4.6 +/- 2.9 nM and 279 +/- 299 fmol/mg protein/h (mean +/- SD, n = 19) for HO, respectively. The aromatase activity was significantly increased by dexamethasone in a dose-dependent manner. Reverse transcription-polymerase chain reaction analysis revealed that dexamethasone increased the transcript of P450AROM gene. Osteoblast-specific promoters were also determined. Dexamethasone and 1 alpha,25-dihydroxyvitamin D3 synergistically enhanced aromatase activity and P450AROM mRNA expression. These results demonstrate that adrenal androgen, DHEA, is converted to E1 in osteoblast by P450AROM which is positively regulated by glucocorticoid and 1 alpha,25-dihydroxyvitamin D3 and important to maintain BMD in the 6 to 7th decade, after menopause.
Publication
Journal: Journal of Neuroscience Research
March/10/1999
Abstract
Astroglial swelling occurs in acute hyperammonemic states, including acute hepatic encephalopathy. In these conditions, the peripheral-type benzodiazepine receptor (PBR), a receptor associated with neurosteroidogenesis, is up-regulated. This study examined the potential involvement of PBRs and neurosteroids in ammonia-induced astrocyte swelling in culture. At low micromolar concentrations, the PBR antagonist PK 11195, atrial natriuretic peptide, and protoporhyrin IX, which are known to interact with the PBR, attenuated (16-100%) the effects of ammonia, whereas the PBR agonists Ro5-4864, diazepam binding inhibitor (DBI51-70), and octadecaneuropeptide exacerbated (10-15%) the effects of ammonia. At micromolar concentrations, diazepam, which interacts with both the PBR and the central-type benzodiazepine receptor (CBR), increased swelling by 11%, whereas flumazenil, a CBR antagonist, had no effect. However, at 100 nM diazepam and flumazenil abrogated ammonia-induced swelling. The neurosteroids dehydroepiandrosterone sulfate, tetrahydroprogesterone, pregnenolone sulfate, and tetrahydrodeoxycorticosterone (THDOC), products of PBR stimulation, at micromolar concentrations significantly enhanced (70%) ammonia-induced swelling. However, at nanomolar concentrations, these neurosteroids, with exception of THDOC, blocked ammonia-induced swelling. We conclude that neurosteroids and agents that interact with the PBR influence ammonia-induced swelling. These agents may represent novel therapies for acute hyperammonemic syndromes and other conditions associated with brain edema and astrocyte swelling.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
November/18/1996
Abstract
Based on indirect evidence, it has often been assumed that the zona reticularis of the adult human adrenal cortex is the source of the adrenal androgens, dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS), but direct tests of this concept have been few. Using the techniques of cell culture, Northern blotting, and RIA, we compared the properties of separated adult zonal cells to those of fetal zone cells, a cell type well known to secrete large amounts of DHEA(S) due to its low expression of 3 beta-hydroxysteroid dehydrogenase (3 beta HSD). In nine glands from donors of a wide age range, the zona fasciculata and zona reticularis were separated and dissociated, and the cells were placed in culture. After 5 days, serum was removed by a 24-h period in serum-free defined medium followed by a 24-h exposure to cAMP analogs, with the optional addition of insulin, also in serum-free medium. The separated fasciculata and reticularis cells showed large differences in the DHEA(S)/cortisol (F) production ratios from added pregnenolone precursor, consistent with the synthesis of only F and essentially no DHEA(S) by fasciculata cells and with the synthesis of mostly DHEA(S) with little or no F by both reticularis cells and fetal zone cells. The different patterns of steroidogenesis were accompanied by a much lower level of expression of type II 3 beta HSD in reticularis cells, similar to that in fetal zone cells. In contrast, other genes were similarly regulated in the two adult zones and in the fetal zone by both cAMP and insulin. The levels of messenger ribonucleic acids for 17 alpha-hydroxylase, cholesterol side-chain cleavage enzyme, 21-hydroxylase, and 11 beta-hydroxylase responded to cAMP and insulin in both reticularis cells and fetal zone cells in the same pattern as that previously established in fasciculata cells. The central role of the limited expression of 3 beta HSD in the DHEA(S)-synthesizing property of reticularis cells was established by inhibition of 3 beta HSD in fasciculata cells with trilostane, which caused them to increase their DHEA/F production ratio to a level exceeding even that in fetal zone cells. There did not appear to any age-related changes in gene expression that could account for the large age-related decline in DHEA(S) biosynthesis in humans in either reticularis or fasciculata cells. Thus, the most likely cause of the age-related decline in adrenal androgen biosynthesis is an age-related decline in the number of functional reticularis cells, without a major change in the differentiated properties of the zonal cells as a function of age.
Publication
Journal: Journal of Clinical Investigation
September/19/1988
Abstract
Dehydroepiandrosterone (DHEA) is an endogenous steroid that blocks carcinogenesis, retards aging, and exerts antiproliferative properties. In vitro, it is a potent inhibitor of glucose-6-phosphate dehydrogenase, the first committed step of the pentose phosphate pathway. In man, serum levels of DHEA and its sulfate peak in early adulthood and drop markedly with age. Epidemiologic evidence indicates that low levels of DHEA or its sulfate conjugate are linked to an increased risk of developing cancer or of death from cardiovascular disease. Like cancer, atherosclerosis is a proliferative process characterized by both initiation and promotion phases. This similarity provided a framework in which to study the antiatherogenic effects of DHEA. Rabbits were randomly assigned to four groups. Two groups of rabbits received aortic endothelial injury by balloon catheter and were fed a 2% cholesterol diet for 12 wk. DHEA, 0.5%, was incorporated into the diet of one group receiving the 2% cholesterol diet and endothelial injury and also into the diet of one of the control groups. Animals were killed after 12 wk and aortas, hearts, and livers were studied. Plasma samples were analyzed for total cholesterol, VLDL, LDL, HDL, triglycerides, DHEA, and DHEA-sulfate levels. The atherogenic insult resulted in severe atherosclerosis in animals not treated with DHEA. In those receiving DHEA there was an almost 50% reduction in plaque size (P = 0.006), inversely related to the serum level of DHEA attained. Fatty infiltration of the heart and liver were also markedly reduced. These beneficial actions were not attributable to differences in body weight gain, food intake, total plasma cholesterol or distribution of cholesterol among the VLDL, LDL, or HDL fractions. The results show that high levels of plasma DHEA inhibit the development of atherosclerosis and they provide an important experimental link to the epidemiologic studies correlating low DHEA-sulfate plasma levels with an enhanced risk of cardiovascular mortality.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/8/1990
Abstract
To discern the pharmacological effects of dehydroepiandrosterone (DHEA) in older women with low endogenous DHEA and DHEA sulfate (DS), 1600 mg/day (in four divided doses) were administered orally to six postmenopausal women for 28 days in a double blind placebo-controlled cross-over study. Serum concentrations of androgens after the first 400-mg dose of DHEA increased rapidly and reached a maximum at 180-240 min, resulting in increases over baseline of 6-fold for DHEA (5.8 +/- 2.1 to 28.8 +/- 5.5 nmol/L), 12-fold for DS (3.0 +/- 1.6 to 28.2 +/- 4.6 mumol/L) and androstenedione (1.4 +/- 0.3 to 19.5 +/- 9.8 nmol/L), 2.5-fold for testosterone (0.7 +/- 0.1 to 2.2 +/- 0.6 nmol/L), and 15-fold for dihydrotestosterone (0.2 +/- 0.06 to 2.73 +/- 1.0 nmol/L), but estrone, estradiol, and sex hormone-binding globulin (SHBG) were unchanged. Assessment at weekly intervals revealed a further increase in all androgens which was maximal at 2 weeks and remained markedly elevated, although it declined somewhat by 4 weeks. The increments observed after 2 weeks of DHEA administration reached 15-fold for DHEA (71.9 +/- 14.2 nmol/L), 9-fold for testosterone (6.5 +/- 1.7 nmol/L), and 20-fold for DS (65.1 +/- 14.9 nmol/L), androstenedione (30.5 +/- 11.5 nmol/L), and dihyrotestosterone (3.8 +/- 1.5 nmol/L). Both estrone and estradiol showed a progressive increase to 2-fold the basal value at 4 weeks. Integrated SHBG and thyroid binding globulin levels decreased (P less than 0.05) during DHEA treatment. However, LH, FSH, body weight, and percent body fat, as measured by underwater weighing, were unaltered during the 4-week experiment. A marked decline of 11.3% (P less than 0.05) in serum cholesterol and 20.0% (P less than 0.05) in high density lipoprotein noted within the first week of DHEA administration persisted for the 28-day period and was accompanied by a nonsignificant downward trend in low density lipoprotein, very low density lipoprotein, and triglycerides. Peak insulin levels during the 3-h oral glucose tolerance test were significantly higher (P less than 0.05) after the 28 days of DHEA (1126 +/- 165 vs. 746 +/- 165 pmol/L) and were accompanied by a 50% increase in the integrated insulin response (P less than 0.01) without a significant change in fasting glucose insulin or glucose-6-phosphate dehydrogenase values.(ABSTRACT TRUNCATED AT 400 WORDS)
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/29/2002
Abstract
Low plasma levels of SHBG and free testosterone have been associated with increased insulin resistance and risk for type 2 diabetes in males. As truncal obesity, a condition accompanied by increased insulin resistance, is also associated with low SHBG and testosterone levels, the independent association of low free testosterone and SHBG with excessive insulin resistance remains to be determined. In this study we evaluated whether in normogonadic men, plasma levels of SHBG and free testosterone are primarily related to insulin resistance or to generalized and regional adiposity. Hyperinsulinemic-euglycemic clamps and iv glucose tolerance tests were performed in 24 healthy volunteer and 33 patients with mild type 2 diabetes. The 2 groups were chosen to have similar body mass index and were found to have similar body composition and fat distribution, assessed by underwater weighing, skinfold thickness, and magnetic resonance imaging of the abdomen. In the 2 groups combined, plasma levels of SHBG correlated inversely with fat accumulation in both sc and intraabdominal areas. Plasma levels of free testosterone correlated inversely with both truncal and peripheral skinfold thickness only in the nondiabetic men. No associations between plasma levels of sex steroid hormones and insulin resistance, hepatic glucose output, or insulin secretion were found to be independent of adiposity. Furthermore, although patients with diabetes were more insulin resistant than those without diabetes, the 2 groups had similar plasma concentrations of free testosterone (55 +/- 14 and 67 +/- 27 pmol/liter, respectively), SHBG (19 +/- 13 and 19 +/- 13 nmol/liter), estradiol (83 +/- 5 and 81 +/- 21 pmol/liter), and dehydroepiandrosterone sulfate (3.6 +/- 2.2 and 2.8 +/- 1.7 nmol/liter). We conclude that in normogonadal nondiabetic males, the variability in plasma bioavailable testosterone concentrations is predictive of the variability in fat deposition in the sc adipose tissue compartments of both truncal and peripheral areas. Low plasma levels of bioavailable testosterone do not independently predict excessive insulin resistance, beta-cell dysfunction, or hepatic glucose output in normogonadal men.
Publication
Journal: Cancer Research
November/3/1999
Abstract
Estrogens stimulate the proliferation of many breast tumors and cell lines derived from them. Antiestrogens have therefore become a powerful therapeutic agent to treat breast tumors that express estrogen receptor (ER) alpha. In addition, aromatase inhibitors are now used in postmenopausal women to block the in situ conversion of adrenal androgens to estrogens. This approach can only be successful if ER-alpha in a particular tumor is not directly stimulated by adrenal androgens. We have examined this possibility using several different cell lines as model systems: (a) wild-type MCF7 cells, an ER-alpha-dependent human breast cancer cell line; (b) MCF7SH cells, an estrogen-independent MCF7 variant; (c) Ishikawa cells, an ER-alpha-containing human uterine cell line; (d) ER-negative HeLa cells; and (e) budding yeast. Transactivation assays with transfected ER-alpha reporter genes reveal a direct activation of ER-alpha by dehydroepiandrosterone (DHEA), 5alpha-androstene-3beta,17beta-diol, testosterone, and the two nonaromatizable androgens, dihydrotestosterone and 5alpha-androstane-3beta,17beta-diol. The involvement of other steroid receptors could be ruled out with specific antihormones. Moreover, the same set of ligands stimulates the proliferation of the two breast cancer cell lines. At subsaturating and physiologically relevant concentrations of DHEA, DHEA stimulates the proliferation of MCF7SH cells, which correlates with a substantial, albeit submaximal, transcriptional response. Thus, adrenal androgens must also be considered as risk factors in postmenopausal women.
Publication
Journal: Journal of Pharmacology and Experimental Therapeutics
April/20/1999
Abstract
A number of endogenous steroids exhibit rapid, nongenomic effects on the central nervous system and are called neuroactive steroids. The rapid mechanisms of action include modulation of gamma-aminobutyric acid type A (GABAA) and N-methyl-D-aspartate (NMDA) receptors, which are two receptors implicated in the behavioral effects of ethanol. It was hypothesized that neuroactive steroids that positively modulate GABAA receptors or negatively modulate NMDA receptors, analogous to the actions of ethanol, would produce discriminative stimulus effects similar to ethanol. Two groups of male Long-Evans rats (n = 6-8/group) were trained to discriminate between 1.0 or 2.0 g/kg ethanol (i.g.) and water (i.g.). The neuroactive steroids allopregnanolone, pregnanolone, epipregnanolone, allotetrahydrodeoxycorticosterone, pregnanolone sulfate, epipregnanolone sulfate, dehydroepiandrosterone, dehydroepiandrosterone sulfate, pregnenolone, and pregnenolone sulfate (PS), all administered i.p., were tested for substitution with acute and cumulative dosing procedures (n = 4-8/steroid). The GABAA-positive modulatory steroids allopregnanolone, pregnanolone, and allotetrahydrodeoxycorticosterone substituted for ethanol, as did the low-efficacy steroid 3beta,5beta-P. GABAA-negative modulators, such as dehydroepiandrosterone sulfate and PS, and all of the NMDA modulators tested, including PS, pregnanolone sulfate, and epipregnanolone sulfate, did not substitute for ethanol. These results show that certain endogenously occurring neuroactive steroids produce discriminative stimulus effects similar to those of ethanol.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
May/17/1992
Abstract
The interconversion of estrone (E1) and 17 beta-estradiol (E2), androstenedione (4-ene-dione) and testosterone (T), as well as dehydroepiandrosterone and androst-5-ene-3 beta,17 beta-diol is catalyzed by 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD). The enzyme 17 beta-HSD thus plays an essential role in the formation of all active androgens and estrogens in gonadal as well as extragonadal tissues. The present study investigates the tissue distribution of 17 beta-HSD activity in the male and female rat as well as in some human tissues and the distribution of 17 beta-HSD mRNA in some human tissues. Enzymatic activity was measured using 14C-labeled E1, E2, 4-ene-dione and T as substrates. Such enzymatic activity was demonstrated in all 17 rat tissues examined for both androgenic and estrogenic substrates. While the liver had the highest level of 17 beta-HSD activity, low but significant levels of E2 as well as T formation were found in rat brain, heart, pancreas and thymus. The oxidative pathway (E2----E1, T----4-ene-dione) was favored over the reverse reaction in almost all rat tissues while in the human, almost equal rates were found in most of the 15 tissues examined. The widespread distribution of 17 beta-HSD in rat and human tissues clearly indicates the importance of this enzyme in peripheral sex steroid formation or intracrinology.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
April/22/1976
Abstract
Serum androgens testosterone (T), testosterone-like-substances (TLS), delta4-androstenedione (delta4), dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA) were measured in 85 normal girls and 101 normal boys grouped according to pubic hair development in Tanner stages I to IV/V. The pattern of change with puberty differed for each androgen. In boys T and TLS rose with the onset of puberty but showed a more abrupt rise later in puberty. DHT also was higher in boys in late puberty but did not demonstrate a steep rise. The other androgens did not show a sex difference at any stage of puberty. While delta4 steroids did not show an increase in the years before onset of puberty, DHEA was significantly higher in prepubertal children over 7 years than in those under 7 years (mean +/- SD 166 +/- 110 vs. 31 +/- 25, P less than 0.005). The most rapid increase of DHEA concentrations was observed with the appearance of pubic hair (Stage II) in boys and girls. This contrasted with the more gradual rise of delta4 in both sexes. The oldest boys and girls (Tanner stages IV/V) had mean concentrations of all androgens in the adult range except for DHT. Twenty-two girls with precocious adrenarche (PA) aged 3-8 years had mean concentrations of T, DHT, delta4 and DHEA that were significantly higher (P less than 0.05) than in prepubertal children, but similar to those of girls in stage II and significantly lower (P less than 0.02) than in late pubertal girls (stage IV/V). Longitudinal studies in 12 of the girls indicated fluctuation of androgen concentrations, especially DHEA, but in general no increase during the years of followup. Precocious adrenarche appears to be a non-progressive disorder associated with an advanced maturation of adrenal androgen to an early pubertal stage. A rise in all androgens measured was correlated with the development of sexual hair.
Publication
Journal: British Journal of Cancer
June/23/1999
Abstract
This paper presents a quantitative review of the data from eight prospective epidemiological studies, comparing mean serum concentrations of sex hormones in men who subsequently developed prostate cancer with those in men who remained cancer free. The hormones reviewed have been postulated to be involved in the aetiology of prostate cancer: androgens and their metabolites testosterone (T), non-SHBG-bound testosterone (non-SHBG-bound T), di-hydrotestosterone (DHT), androstanediol glucuronide (A-diol-g), androstenedione (A-dione), dehydroepiandrosterone sulphate (DHEAS), sex hormone binding globulin (SHBG), the oestrogens, oestrone and oestradiol, luteinizing hormone (LH) and prolactin. The ratio of the mean hormone concentration in prostate cancer cases to that of controls (and its 95% confidence interval (CI)) was calculated for each study, and the results summarized by calculating the weighted average of the log ratios. No differences in the average concentrations of the hormones were found between prostate cancer cases and controls, with the possible exception of A-diol-g which exhibited a 5% higher mean serum concentration among cases relative to controls (ratio 1.05, 95% CI 1.00-1.11), based on 644 cases and 1048 controls. These data suggest that there are no large differences in circulating hormones between men who subsequently go on to develop prostate cancer and those who remain free of the disease. Further research is needed to substantiate the small difference found in A-diol-g concentrations between prostate cancer cases and controls.
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