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Publication
Journal: Fertility and Sterility
March/2/2016
Abstract
OBJECTIVE
To reexamine associations between polycystic ovarian morphology (PCOM) and degree of symptomatology in polycystic ovary syndrome (PCOS) using a well-defined PCOS population, newer ultrasound technology, and reliable offline assessments of sonographic parameters.
METHODS
Cross-sectional observational study.
METHODS
Academic hospital and clinical research unit.
METHODS
Forty-nine women with PCOS as defined by hyperandrogenism and oligoamenorrhea.
METHODS
None.
METHODS
Number of follicles per follicle size category, antral follicle count (AFC), ovarian volume (OV), follicle distribution pattern, stromal area, ovarian area, stromal to ovarian area ratio (S/A) and stromal echogenicity index (SI), total (TT), androstenedione, LH, FSH, cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, C-reactive protein, glucose, insulin, and hemoglobin A1C, menstrual cycle length, hirsutism score, body mass index (BMI), waist:hip ratio, and blood pressure.
RESULTS
AFC, but not OV, was positively associated with TT (ρ = .610), androstenedione (ρ = .490), and LH:FSH (ρ = .402). SI was positively associated with androgen markers and LH:FSH, while S/A was negatively associated with these variables. Follicles ≤4 mm were negatively associated with various metabolic markers, whereas larger follicles (5-8 mm) showed positive associations. Stromal markers were not associated with cardiometabolic measures. LH:FSH best predicted follicles ≤4 mm, and BMI predicted 5- to 9-mm follicles. Dominant follicles ≥10 mm were best predicted by age.
CONCLUSIONS
AFC, and not OV, reflected the severity of reproductive dysfunction in PCOS. Associations among different sized follicles were consistent with recruitable sized follicles, which reflects the severity of metabolic dysfunction in PCOS.
Publication
Journal: Endocrinology
November/19/1985
Abstract
The actions of cholinomimetics on androgen biosynthesis were investigated using a primary culture of testicular cells derived from adult hypophysectomized rats. Testicular cells were maintained in serum-free medium and treated with hCG and/or drugs on day 8 of culture. Media were collected 2 days later for measurement of steroids and cAMP. Treatment with hCG increased testosterone production 50-fold over control values, whereas treatment with cholinomimetics alone failed to increase androgen production. Concomitant treatment of testicular cells with nicotinic cholinergic agonists (lobeline, nicotine, and dimethylphenylpiperazinium iodide) inhibited hCG-stimulated androgen biosynthesis in a dose-dependent fashion, with IC50 values of 3 X 10(-5), 1.7 X 10(-<em>4</em>), and greater than 10(-3) M, respectively. In contrast, two muscarinic cholinergic agonists, muscarine and bethanechol, failed to inhibit androgen production at concentrations up to 10(-3) M. A ganglionic nicotinic antagonist (hexamethonium), but not a skeletal muscle nicotinic antagonist (decamethonium), partially blocked the actions of lobeline. Lobeline (10-<em>4</em>) M) decreased hCG-stimulated testosterone production (50-75%) throughout the 2-day culture period; however, this inhibition was reversible upon removal of the drug. Lobeline also inhibited hCG-stimulated cAMP accumulation as well as testosterone production induced by cholera toxin (65% inhibition), forskolin (50% inhibition), or (Bu)2cAMP (70% inhibition). Lobeline inhibition of hCG-stimulated testosterone production was accompanied by decreases in medium accumulation of 17 alpha-hydroxypregnenolone (75%), 17 alpha-hydroxyprogesterone (85%), dehydroepiandrosterone (50%), and <em>androstenedione</em> (61%); however, the medium content of pregnenolone and progesterone were unchanged. Additional experiments demonstrated that lobeline suppressed the conversion of exogenous progesterone to testosterone, but did not affect the conversion of exogenous 17 alpha-hydroxyprogesterone to testosterone. These results indicate that nicotinic, but not muscarinic, cholinergic agonists inhibit androgen biosynthesis through selective inhibition of 17 alpha-hydroxylase activity. Thus, endogenous acetylcholine may be involved in the negative regulation of testicular steroidogenesis.
Publication
Journal: Steroids
May/15/1990
Abstract
Reaction kinetics of the aromatase enzyme and of a new nonsteroidal aromatase inhibitor, R 76 713 (6-[(<em>4</em>-chlorophenyl)(1H-1,2,<em>4</em>-triazol-1-yl)-methyl]-1-methyl-1H- benzotriazole), were studied in ovarian homogenates obtained from pregnant mare's serum gonadotropin (PMSG)-injected female Wistar rats. The Km (Michaelis constant) of the aromatase enzyme with <em>androstenedione</em> as the substrate was <em>4</em>7 +/- 13 nM; for testosterone as the substrate, a value of 159 +/- 10 nM was found. In the presence of increasing concentrations of R 76 713, the Km increased while the Vmax (maximal velocity of enzyme-catalyzed reaction) remained unchanged. Using <em>androstenedione</em> and testosterone as the substrate, Lineweaver-Burk analysis of the data showed a Ki (dissociation constant of the enzyme-inhibitor complex) for R 76 713 of 0.7 +/- 0.3 nM and 1.6 +/- 0.<em>4</em> nM, respectively. R 76 713 appeared to competitively inhibit the rat ovarian aromatase.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
March/22/2006
Abstract
Studies to elucidate the role of dehydroepiandrosterone (DHEA) metabolism in neuroprotection have compared its relative 7-hydroxylation against estrogen formation by way of <em>4</em>-<em>androstenedione</em> (AD) in various rodent brain cell lines. In all cases, the 7alpha- and 7beta-hydroxy epimers of DHEA were found to be the dominant products with one notable exception. BV2 mouse microglia were virtually unable to hydroxylate DHEA at C-7 and converted AD to a major unknown metabolite not observed with mouse BHc hippocampal cells. In this paper, we describe the identification of this compound based on its physical properties and analysis by TLC and HPLC. Its identity as 3beta-hydroxy-<em>4</em>-androstene-17-one, the Delta(<em>4</em>)-isomer of DHEA, was confirmed by mass spectrometry (LC/MS), as well as by reverse isotope dilution analysis involving co-crystallization with the synthetic steroid. Possible mechanisms for the formation of this isomer of DHEA by BV2 microglia are proposed, together with that of other C-19 steroids detected which include testosterone (T), 5alpha-dihydrotestosterone and 5alpha-androstanedione.
Publication
Journal: Endocrinology
March/2/1988
Abstract
Inhibin levels in the serum-free media of primary Sertoli cell-enriched (SCE) cultures were studied as a function of time and hormonal treatment. SCE cultures were established from 20-day-old rats and maintained in SF media supplemented with insulin, transferrin, epidermal growth factor (EGF), and bacitracin. Radioimmunoassayable inhibin was measured using an antibody directed against a synthetic porcine inhibin-alpha (pI alpha) and measured using this same synthetic peptide as well as a highly purified ovine inhibin standard. Results of these determinations are expressed in terms of a synthetic peptide as femtomoles of pI alpha-(1-26)-G-Y-per ml/10(6) cells. Inhibin levels (+/- SEM) that accumulated at this rate in media from control cultures were 18<em>4</em>.9 +/- 6.1 and 167.<em>4</em> +/- 5.2 on days 0-<em>4</em> and <em>4</em>-8, respectively. When FSH (oFSH 17; 1-1000 ng/ml) was added, a dose-dependent increase in inhibin levels was significant at all time points beyond the initial 2<em>4</em> h. The simultaneous addition of 2 x 10(-7) M testosterone (T) with low doses of FSH addition of 2 x 10(-7) m testosterone (T) with low doses of FSH suppressed the inhibin response to FSH, but when T was combined with 300 ng/ml FSH, there was no effect of T on inhibin levels compared to FSH alone, regardless of time in culture. In spite of the modest effect of T, <em>androstenedione</em> (A; 2 x 10(-13) to x 10(-5) M) produced a dose-dependent suppression of inhibin levels. This inhibition was also observed at all doses of FSH. The action of A was not due to its conversion to estrogens, as 17 beta-estradiol had no effect on inhibin production by SCE cultures in either the presence or absence of FSH. The effect of EGF, a component of the basal serum-free medium, was next examined; it produced a 1.5-fold higher level of inhibin (188.7 +/- 9.5) compared to cultures without EGF (135.6 +/- 5.0). When SCE cultures were plated with FSH plus EGF, the stimulation of inhibin levels was additive. We conclude that in Sertoli cell cultures established from immature rats (1) the accumulation of inhibin in medium declines from 90 fmol/10(6) cells.day (initial 2<em>4</em> h) to <em>4</em>0-50 fmol/10(6) cells.day (over the first <em>4</em>8 h) and continues to accumulate in the medium for 8 days of culture; (2) FSH regulates the production of inhibin by Sertoli cells; the best dose response is observed over a 3-day period.(ABSTRACT TRUNCATED AT <em>4</em>00 WORDS)
Publication
Journal: General and Comparative Endocrinology
November/9/1998
Abstract
Steroid hormone metabolic clearance pathways are susceptible to induction and suppression resulting from exposure to many xenobiotics. These biochemical effects have the potential to alter steroid hormone homeostasis and, ultimately, steroid hormone-dependent processes such as growth, development, and reproduction. In this study, the metabolic clearance of 17beta-hydroxy-<em>4</em>-androsten-3-one (testosterone) by adult male, adult female, and juvenile fathead minnows (Pimephales promelas) was evaluated. Individual elimination metabolites were identified and rates of metabolite elimination were quantified. Fathead minnows produced a variety of testosterone metabolites including oxido-reduced, hydroxylated, and conjugated derivatives. Metabolites identified by TLC/GC/MS included <em>4</em>-androstene-3,17-dione (<em>androstenedione</em>), 17beta-hydroxy-5alpha-androstan-3-one (5alpha-dihydrotestosterone), 5alpha-androstane-3alpha,17beta-diol (3alpha-androstanediol), 5alpha-androstane-3beta,17beta-diol (3beta-androstanediol), 17beta-hydroxy-<em>4</em>-androstene-3,11-dione (11-ketotestosterone), 16beta-hydroxy-<em>4</em>-androsten-3-one (16beta-hydroxytestosterone), and 6beta-hydroxy-<em>4</em>-androsten-3-one (6beta-hydroxytestosterone). Testosterone and its metabolites were eliminated in both free and conjugated form. Adult male, adult female, and juvenile fathead minnows eliminated the same profile of testosterone metabolites. However, adult females eliminated androstanediols at a significantly greater rate than did males, and juvenile fish eliminated nearly all testosterone metabolites at greater weight-normalized rates than did adults. These results demonstrate that fathead minnows extensively metabolize testosterone leading to its elimination and provide the foundation upon which the effects of xenobiotics on testosterone metabolism can be assessed.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
February/19/1986
Abstract
<em>Androstenedione</em> and testosterone were measured in whole adrenal glands of 56 previously healthy boys who died suddenly between birth and 2 yr of age. In each adrenal gland, the concentration of <em>androstenedione</em> considerably exceeded that of testosterone. The highest concentrations were found during the first week of life (median, 295 ng/g; range, 98-320 ng/g). Thereafter, values decreased rapidly until the end of the first year of life (median, 10 ng/g; range, <em>4</em>.<em>4</em>-22.7 ng/g). Adrenal testosterone concentrations averaged 15% of those of <em>androstenedione</em> in the same gland and similarly decreased until the end of the first year. The decrease of adrenal androgen concentrations paralleled the involution of the fetal adrenal zone. A close correlation existed between the concentration of <em>androstenedione</em> in adrenal tissue and plasma. However, no correlation existed between adrenal and plasma testosterone. When the adrenals and testes of the same infant were compared, there was 10 times more <em>androstenedione</em> in the adrenals than in the testes during the first 2 yr of life. The testes contained more testosterone than the adrenals only during the first <em>4</em> months. Thus, in infant boys the adrenals are the main source of <em>androstenedione</em> during the first 2 yr. After the sixth month of life, they also are the main source of testosterone.
Publication
Journal: Biochemical Pharmacology
October/13/1993
Abstract
Adult white Leghorn chickens exhibited a sexual dimorphism in hepatic microsomal monooxygenases determined from the concentrations of total cytochromes P<em>4</em>50 and b5, and the metabolism of drug (hexobarbital, coumarin and ethoxyresorufin) and steroid (<em>androstenedione</em> and testosterone) substrates that were 2- to <em>4</em>-fold greater in roosters than in hens. Caponizing at 6 weeks of age reduced the activities of the monooxygenases to levels comparable to those found in intact hens. In spite of the fact that testosterone replacement maximally stimulated comb growth in the capons and elevated (i.e. masculinized) hepatic monooxygenase activities in the hens to male-like levels, androgen replacement was ineffective in increasing the subnormal enzyme levels in the capons. While the failure of testosterone administration to restore monooxygenase levels in the capons may be explained by the immaturity of the birds at orchiectomy, the present results demonstrate, that like some mammals, birds may display gender differences in hepatic monooxygenases that are regulated by the testes.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
October/16/1991
Abstract
Extending a series of previous investigations on the regulatory interaction of insulin and androgens, this study tests the hypothesis that the physiological insulinemia after oral glucose suppresses circulating dehydroepiandrosterone (DHEA), dehydroepiandrosterone-sulfate (DHEA-S), and <em>androstenedione</em> (delta <em>4</em>A) delta <em>4</em> in normal women. Accordingly, seven normal weight, ovulatory women were randomized to receive first either a 75 g glucose dose or a sham control for diurnal rhythm consisting of distilled water at 1700 h. After this insulin stimulus, DHEA-S suppressed below sham control at 90 and 120 min (P less than 0.05) whereas delta <em>4</em>A suppress at 60, 90, and 120 min (P less than 0.05). Furthermore, as serum insulin increased after glucose, DHEA-S (r2 = 0.351, P less than 0.05) and delta <em>4</em>A (r2 = 0.31<em>4</em>, P less than 0.05) decreased in an inverse linear relationship with insulin. There was no significant suppression below sham at any point in time for DHEA, testosterone, or cortisol. Thus, the endogenous serum insulin response after oral glucose in normal women is associated with suppression of serum DHEA-S and delta <em>4</em>A with absence of testosterone and cortisol suppression.
Publication
Journal: Journal of clinical chemistry and clinical biochemistry. Zeitschrift fur klinische Chemie und klinische Biochemie
September/24/1984
Abstract
In the analysis of steroid hormones careful attention is usually paid to blood collection and plasma storage. However, the appropriate care of samples cannot always be assured in routine work with steroids. Therefore, the stability of cortisol, aldosterone, 17-hydroxyprogesterone, testosterone, <em>androstenedione</em>, dehydroepiandrosteronesulphate, oestrone, oestradiol, sex hormone binding globulin (SHBG) and, the binding of testosterone and cortisol to plasma proteins in blood and plasma were studied before and after various handling procedures. Ten cycles of alternate freezing and thawing of plasma did not significantly affect the levels of the steroids or their plasma binding. The greatest differences, compared with controls, were seen for aldosterone (-6.2%) and oestradiol (-5.3%). Plasma storage at -28 degrees C was hardly superior to a <em>4</em> days storage at <em>4</em> degrees C (refrigerator) or 22 degrees C (room temperature). Although <em>androstenedione</em> (-10.9%), oestrone (-10.2%) and oestradiol (-12.2%) levels decreased by more than 10%, the means of all analyses were still in the 2 SD range. Even SHBG and the steroid binding were only slightly affected by temperature. When whole blood was stored at <em>4</em> degrees C or 22 degrees C, the resulting values differed from those obtained with plasma, but the differences were usually less than 10%. Although the levels were within the 2 SD range, whole blood showed a decrease of 12.3% for aldosterone and 1<em>4</em>.5% for <em>androstenedione</em>. In contrast, plasma binding of testosterone (25.9%) and cortisol (15.1%) were substantially affected by storage at 22 degrees C in whole blood. It is concluded that repeated freezing and thawing of plasma, or storage at various temperatures have only a small effect on the measured levels of steroids and their plasma binding. Although it is not advisable, even whole blood may be used for the analysis of steroid concentrations.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
September/2/2004
Abstract
Ovarian steroid secretion capacity starts to decline as early as around the age of 30 yr. Whether an age-related decrease in androgen secretion, as in normal women, also occurs in women with polycystic ovary syndrome (PCOS) and whether the enhanced androgen production in PCOS remains throughout the fertile period of life are not known. The aim of this study was to determine the age-related serum basal and gonadotropin-stimulated androgen levels in women with PCOS and to compare the results with those obtained from our previous study in healthy women with normal ovaries. Human chorionic gonadotropin (hCG) stimulation tests were carried out among <em>4</em>2 women with PCOS (age, 16-<em>4</em><em>4</em> yr; body mass index, 31.02 +/- 1.1 kg/m(2)). An im injection of 5000 IU hCG was given 2-<em>4</em> d after spontaneous or progestin-induced menstrual bleeding, and blood samples for LH, FSH, inhibin B, 17-hydroxyprogesterone, <em>androstenedione</em> (A), testosterone (T), and estradiol assays were collected at 0, 2<em>4</em>, <em>4</em>8, and 96 h. In women with PCOS, basal serum T and A levels were about 50% higher than in healthy women. The responses of A and T to hCG [area under the curve (AUC), 96 h)] were significantly higher in women with PCOS than in normal women [A, 1183.6 +/- 60 (+/-se) vs. 81<em>4</em>.<em>4</em> +/- 39 (P <or= 0.001); T, 192.9 +/- 12 vs. 117.<em>4</em> +/- 6; P <or= 0.001]. In PCOS women, the hCG-stimulated A levels correlated negatively with age (AUC of A: r = -0.0<em>4</em><em>4</em>; P = 0.00<em>4</em>), and a similar trend was also observed in AUC T levels (AUC of T: r = -0.125, P = 0.<em>4</em>25). Despite the higher androgen secretion capacity in PCOS, the basal and hCG-stimulated serum estradiol levels were similar to those observed in normal women. LH correlated positively with age, but basal FSH and inhibin B levels remained unchanged. In conclusion, in PCOS basal serum levels of androgens and ovarian androgen secretion capacity are markedly increased and remain high throughout the reproductive years, although the decreasing ovarian capacity to release androgens in response to hCG stimulation seen in healthy women also occurs in PCOS.
Publication
Journal: Journal of Endocrinology
May/20/1981
Abstract
The metabolism in vitro of [<em>4</em>-1<em>4</em>C]testosterone to reduced derivatives was studied in the pituitary gland, hypothalamus and hyperstriatum dorsale of cockerels from hatch to sexual maturity. The most important metabolites were 5 beta-dihydrotestosterone (5 beta-DHT), 5 beta-androstane-3 alpha, 17 beta-diol (5 beta-3 alpha-diol) and 5 beta-androstane-3 beta, 17 beta-diol. Trace amounts of <em>androstenedione</em> and, in the hypothalamus only, of 5 alpha-DHT were also detected. The amounts of 5 beta-reduced metabolites produced by all neuroendocrine tissues declined progressively during maturation with the steepest fall occurring during the first 2 weeks after hatch. At all ages studied, 5 beta-DHT was formed to the greatest extent by the hyperstriatum dorsale, to a lesser extent by the hypothalamus and in the smallest quantities by the pituitary gland. In the three tissues studied, 5 beta-3 alpha-diol tended to be formed to the greatest extent by the pituitary gland. No significant change was observed in the metabolism of testosterone to reduced derivatives in any of the neuroendocrine tissues after castration. It was concluded that in the cockerel, unlike the rat, a change in 5 alpha-reductase activity of the neuroendocrine tissues is unlikely to be involved in the initiation of puberty. The physiological significance of 5 beta-reductase activity in the neuroendocrine tissues remains to be established.
Publication
Journal: Fish Physiology and Biochemistry
November/14/2013
Abstract
Changes in ovarian steroidogenesis accompanying oocyte maturation and ovulation were studied in the African catfish,Clarias gariepinus. Laboratory-reared females with postvitellogenic ovaries were treated with pimozide and LHRH-analogue. The plasma gonadotropin levels were determined by means of a homologous radioimmunoassay, the condition of the ovaries was studied by histological examination of the follicles, and the steroidogenetic capacity of the ovaries was analyzed byin vitro incubation of tissue fragments for 3 h with [(3)H]-pregnenolone and [(3)H]<em>androstenedione</em> as precursors. Data were collected at regular intervals between 0 and 16 h after pimozide-LHRH analogue administration.Until <em>4</em> h after the beginning of the experiments the plasma gonadotropin levels did not rise above 25 ng/ml, the ovaries remained in the stage of postvitellogenesis, and testosterone was the main end product of steroidogenesis. Four hours later the gonadotropin concentration in the blood had risen to more than 150 ng/ml, and the ovaries had entered the stage of germinal vesicle migration. At the same time steroidogenesis shifted towards the production of 17α,20β-dihydroxy-<em>4</em>-pregnen-3-one, 5β-pregnane-3α, 17α-diol-20-one, 5β-pregnane-3α,6α,17α-triol-20-one, 5β-pregnane-3α,17α,20β-triol and 5β-pregnane-3α,6α,17α,20β-tetrol. During the subsequent stage of germinal vesicle breakdown the plasma gonadotropin level remained high, and the synthesis of the C21-steroids showed a further increase. Simultaneously, the production of some C19-steroid glucuronides was enhanced. The preovulation and especially the postovulation stages were accompanied by a gradual decrease in steroidogenic capacity of the ovaries, even though the plasma gonadotropin level remained high. It is concluded that the prematuration surge of gonadotropin influences the activity of enzymes involved in steroidogenesis, leading to a reduced C17,20-lyase and to an augmented activity of the enzymes 20β-hydroxysteroid dehydrogenase (HSD), 5β-reductase, 3α-HSD, 6α-hydroxylase and UDP-glucuronosyltransferase. During ovulation the activity of all steroidogenic enzymes, including such key enzymes as 3β-HSD and 17α-hydroxylase, gradually decreases.Not only 17α,20β-dihydroxy-<em>4</em>-pregnen-3-one, but also the 5β-reduced pregnanes may be involved in inducing oocyte maturation and/or ovulation. The very polar triol and tetrol products may function, together with the steroid glucuronides as sex pheromones.
Publication
Journal: Menopause
May/6/2004
Abstract
OBJECTIVE
To determinate the profile of androstenedione (A), total (T), and free testosterone (FT), dehydroepiandrosterone (DHEA), DHEA-sulphate (DHEAS), sex hormone-binding globulin (SHBG), insulin-like growth factor-I (IGF-I) and IGF-binding protein-3 (IGFBP-3) in non-smoking, postmenopausal women of normal weight and to search for correlations between hormones and carrier proteins and chronological age, number of years of postmenopause and age of onset of menopause.
METHODS
A group of 149 postmenopausal women aged 49 to 74 years were divided into three groups based on the number of years of postmenopause: 2-4 years (group A), 9-12 years (group B), and 19 years or more (group C). Seventy-two women aged 21 to 35 years were the controls. Hormones and carriers were assessed in all groups.
RESULTS
A, DHEA, DHEAS, and IGF-I were significantly lower than controls in all groups, whereas T, FT, SHBG, and IGBFP-3 were lower only in groups B and C. All hormones and carriers were negatively correlated with the number of years of postmenopause; DHEA and T also showed a positive correlation with the age of onset of menopause.
CONCLUSIONS
Androgens, SHBG, and IGF-I/IGFBP-3 show a diversified decline in postmenopause that is involved in the physiological aging process. Thus, a modification, in excess or deficiency, could favor the development of central symptoms or pathologies.
Publication
Journal: European Journal of Obstetrics, Gynecology and Reproductive Biology
March/4/1992
Abstract
The follicular fluid (FF) content of androgens, estrogens and epidermal growth factor (EGF) has been evaluated in a group of patients with policystic ovary disease (PCO) and in one of normally-ovulating infertile women (NOW) in an IVF/ET program. The in vitro response to follicle-stimulating hormone (FSH) has been also evaluated in granulosa luteal cells from the same patients. PCO patients showed significantly higher FF <em>androstenedione</em> (delta <em>4</em>) and testosterone (T) and similar FF estrone (E1) and 17 beta-estradiol (E2) levels compared to controls. In vitro production of E1 and E2 by granulosa luteal cells from PCO patients and from controls were overlapping and their response to FSH was similar. These data indicate a normal intrinsic potential aromatase activity in ovaries from PCO patients stimulated with gonadotropins and suggest that PCOs do not derive from inherent ovarian aromatase deficiency. Increased FF androgen content following gonadotropin stimulation may result from theca cell hyperactivity and androgen accumulation in the follicular antrum of rescued hyperandrogenic follicles as well as from inhibitory factors that may inhibit aromatase activation in vivo, partially counteracting the effect of gonadotropins. FF EGF levels were significantly higher in the group of PCO patients compared to those of NOW. EGF may play a role in blunting the in vivo response of granulosa cells to gonadotropins.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
June/2/2014
Abstract
BACKGROUND
Does adipose tissue produce steroid hormones like an endocrine organ?
OBJECTIVE
To clarify whether adipose tissue produces sex steroid hormone like an endocrine organ, we estimated several key steroid hormone levels, as well as CYP17 and CYP19 activity, in ovariectomized, pre- and postmenopausal women by liquid chromatography-tandem mass spectrometry (LC-MS/MS).
METHODS
The subjects were 19 premenopausal (n = 12), postmenopausal (n = <em>4</em>), and ovariectomized women (n = 3) aged 27-68 years. Serum, visceral adipose and sc adipose samples were taken from these subjects and stored at -70°C. The levels of cortisol, cortisone, progesterone (Prog), <em>androstenedione</em>, dehydroepiandrosterone, estrone, estradiol (E2), and T in serum and adipose tissue were estimated simultaneously by LC-MS/MS. CYP17 and CYP19 activity in tissues were assayed with the use of (13)C-labeled steroid precursors and LC-MS/MS-based estimation of the metabolites.
RESULTS
E2 and Prog levels in the sera of postmenopausal or ovariectomized women were less than 10% of those in premenopausal women. No marked variations were seen in other hormones. Estrone, androstenedione, dehydroepiandrosterone, and Prog levels in the visceral and sc tissues of postmenopausal and ovariectomized women were 9-60 times higher than those in serum, whereas E2 and T levels were 3- to 7-fold higher than those in serum, and cortisol and cortisone levels were 20% of those found for serum. CYP17 in adipose tissue was found to have 17-hydroxylase and 20,17-lyase activity, with each catalytic activity being essentially equal. Therefore, CYP17 in adipose tissue is of the testicular/ovarian type but not adrenal type, which has 17-hydroxylase activity dominant. The presence of CYP19 activity in adipose tissue was approximately 3% of CYP17.
CONCLUSIONS
Our findings suggest that adipose tissue acts as an endocrine organ, with CYP17 and CYP19 activity playing an essential role in sex steroid hormone biosynthesis.
Publication
Journal: Journal of Clinical Endocrinology and Metabolism
March/30/1987
Abstract
Aromatase activity (AR) was studied in pubic skin fibroblasts from eight patients with isolated gynecomastia (PSFG) and five normal subjects (PSFC). Cell monolayers were incubated in the presence of [3H]<em>androstenedione</em> (2 nM) for <em>4</em> or 2<em>4</em> h. Culture medium was extracted after addition of [1<em>4</em>C] carriers to monitor recovery. Metabolites were separated by two successive chromatographic steps. Estrone (E1) and estradiol (E2) were characterized by crystallization, the other metabolites: 16-hydroxyestrone (16 alpha-OHE1) estriol (E3), and epiestriol (epiE3) by their chromatographic migration. AR was expressed either as femtomoles of E2 per microgram DNA (ARE2) or as total aromatized metabolites (ART = E1 + E2 + 16 alpha-OHE1 + E3 + epiE3/microgram DNA). After <em>4</em> h of incubation, no ARE2 could be measured in PSFC; it was low but significant in PSFG (0.03 +/- 0.02 (SEM) fmol/microgram DNA, P less than 0.01). The difference in ART was even more striking: 0.28 +/- 0.1 fmol/microgram DNA in PSFC, 3.15 +/- 2.88 in PSFG (P less than 0.05). 16 alpha-OHE1 represented in this latter group 62.5% of total aromatized metabolites vs. 39% in PSFC. After 2<em>4</em> h, ART was <em>4</em>.17 +/- 3.70 and 1.02 +/- 0.<em>4</em>2 fmol/microgram DNA in PSFG and PSFC, respectively (P less than 0.05); E3 + epiE3 represented 50% of the metabolites in both groups. In conclusion, AR is increased in PSFG relative to PSFC and an important oxidative metabolism of estrogens exists in both types of cells. This increased peripheral AR could result in increased formation of estrogens at the target cell site and represent an element of androgen-estrogen imbalance which would favor the development of gynecomastia.
Publication
Journal: Anticancer Research
February/5/1987
Abstract
Ninety postmenopausal women with advanced breast cancer were randomly assigned to be treated with HD-MPA administered either by oral route (daily dose 900 mg) or by intramuscular injections (1 g IM daily X 5 q w during <em>4</em> consecutive weeks followed by maintenance with 1 g twice weekly). Among 78 evaluable cases, most heavily pretreated, remissions, lasting for a median duration of 11 months, were more frequent on oral (8/37 = 22%) than on IM therapy (5/<em>4</em>1 = 12%). In both arms, high estrogen receptor levels and various clinical factors were associated with higher response rates i.e., age greater than 60, Karnofsky greater than 70, light prior systemic treatment. Side-effects, consisting mainly of weight gain, hypertension and tremor occurred with equal frequency on oral or IM treatment. Five patients complained of pain at the sites of IM injections. Thus, we recommended that, whenever possible, the oral route should be preferred. During the same study, in 20 patients (11 on oral and 9 on IM therapy), blood was drawn at 0, 30, and 60 days of treatment for the assessment of MPA and hormone levels. In both arms, at 60 days, comparable levels of circulating MPA were obtained, with a very significant drop of cortisol, <em>androstenedione</em>, and estrone. These endocrine results, together with our clinical data, indicate that HD-MPA therapy is active on estrogen-dependent tumors with the same specificity as that of other modalities aiming to suppress the adrenal function. Its antineoplastic action in humans could be ascribed at least in part to its suppressive action on the adrenals, resulting in a severe estrogenic deprivation in postmenopausal women.
Publication
Journal: Kidney International
April/12/1981
Abstract
The effects of chronic renal failure on the pituitary-testicular axis of 31 males, aged 11.7 to 20.0 yr (mean, 16.0 yr) were studied. Nine patients not on hemodialysis (group I) had serum creatinines between 2.5 and 8.0 mg/dl, 10 patients were on hemodialysis (group II) and 12 patients had received a renal transplant (group III). The Tanner stage of pubertal development was delayed relative to chronologic age. Testosterone (T), delta <em>4</em>-<em>androstenedione</em> (delta <em>4</em>), and urinary 17-keto steroids were normal when related to pubertal stage in groups I and II; and dehydroepiandrosterone (DHEA) and DHEA sulfate (DS) were in the low normal range. In group III, adrenal androgens (delta <em>4</em>, DHEA, DS) were decreased as a consequence of prednisone therapy whereas T was normal. Luteinizing hormone levels were normal in all. Follicle-stimulating hormone levels were normal in all. Follicle-stimulating hormone (FSH) was significantly increased in groups I and II. In group III, FSH was normal in 6 of 9 patients with serum creatinine concentrations < 2 mg/dl. FSH levels were uniformly elevated in Tanner I-V patients with creatinines>> 2 mg/dl. The data shows that FSH is elevated in patients with chronic renal failure even in prepuberty and early adolescence. This may reflect damage to germinal epithelium prior to the advent of spermatogenesis, whereas Leydig cell function appears to remain intact.
Publication
Journal: British Journal of Cancer
March/16/1993
Abstract
Eighteen consecutive patients with measurable locally advanced or metastatic pancreatic adenocarcinoma were treated with goserelin (Zoladex) 3.6 mg subcutaneously every <em>4</em> weeks. Hydrocortisone 20 milligrams twice daily was commenced with the second injection of goserelin. Objective tumour response was monitored by computerised tomography of the abdomen. There was no objective remission in disease sites. Serial measurements of serum tumour markers showed no reduction in serum CA 19-9 and CA 195 concentrations. The median duration of survival of all cases was 5 months. Administration of goserelin resulted in significant reductions in oestradiol, testosterone, <em>androstenedione</em> in males and reductions in FSH and LH in both males and females. The addition of hydrocortisone resulted in further reductions of <em>androstenedione</em> and testosterone levels in males. Thus goserelin showed no anti-tumour effect, but concentrations required for direct inhibitory effects may be higher than those required to produce effects on hormone suppression.
Publication
Journal: European Journal of Clinical Investigation
July/12/1990
Abstract
To investigate the sex-hormone profiles associated with chronic alcoholism in women we examined 16 non-cirrhotic alcohol abusers (aged 18-<em>4</em>6 years). They were admitted for the treatment of alcoholism (duration of 2-16 yrs) to a social hospital for 6 weeks. Their mean daily alcohol consumption was 170 g. Blood samples for serum LH, FSH, prolactin (PRL), oestrone (E1), oestradiol (E2), progesterone (P), 17-alpha-hydroxyprogesterone (17-OHP), <em>androstenedione</em> (A) and dehydroepiandrosterone (DHEA) were drawn three times a week during the hospital stay. Similar blood samples were taken from 10 control women during one menstrual cycle. The cycles were anovulatory in two patients and in none of controls. Serum LH and FSH levels were similar in alcoholic and control women but serum concentrations of PRL were increased 2-<em>4</em>-fold in alcoholic women. In the patients serum, concentrations of E1 and E2 tended to be lower during the follicular and midcycle phases, as did those of P and 17-OHP during the luteal phase. Compared with the controls, serum levels of A were increased 2-3-fold in the patients. A parallel difference between the two groups was seen in serum DHEA concentrations. We conclude that until liver injury, even heavy alcohol drinking has only minor effects on the secretion of gonadotrophins and ovarian steroids. Hypersecretion of PRL and adrenal androgens may well be an initiating mechanism for sexual dysfunction of female alcoholics.
Publication
Journal: The American journal of physiology
August/26/1981
Abstract
Histologic, hormonal, and enzymatic studies were performed in the rabbit and dog to identify maturational changes similar to human adrenarche. Development of an adrenal reticular zone was observed in both the rabbit and dog, analogous to the change in the man. Plasma dehydroepiandrosterone (DHA) and <em>androstenedione</em> (delta <em>4</em>-A) increased significantly in postpubertal compared to prepubertal male rabbits and dogs, but the increases were much smaller than those reported in man. Orchiectomy reduced plasma DHA and delta <em>4</em>-A of adult rabbit and dog to near undetectable levels, suggesting a primarily testicular origin. The activities of adrenal microsomal 17-hydroxylase and 17,20-desmolase in the orchiectomized rabbit and dog were subsequently measured to explain this apparent low adrenal contribution to DHA and delta <em>4</em>-A. Adrenal 17-hydroxylase activity in the rabbit ad 17,20-desmolase activity in both the rabbit and dog were significantly lower than in an adrenal androgen-secreting primate (cynomolgus macaque). Adrenal 17-hydroxylase activity in the dog, measured 1 wk after castration, doubled after sexual maturation (P less than 0.001). This change was paralleled by a significant rise in basal and ACTH-stimulated plasma 17-hydroxyprogesterone in the intact dog (P less than 0.05). Because adrenal 17-hydroxylase activity has been shown to increase during adrenarche in man, this change may be homologous to human adrenarche.
Publication
Journal: Reproduction
March/17/2014
Abstract
The microenvironment of the developing follicle is critical to the acquisition of oocyte developmental competence, which is influenced by several factors including follicle size and season. The aim of this study was to characterise the metabolomic signatures of porcine follicular fluid (FF) collected from good and poor follicular environments, using high-resolution proton nuclear magnetic resonance (1H-NMR) spectroscopy. Sow ovaries were collected at slaughter, <em>4</em> days after weaning, in summer and winter. The contents of small (3-<em>4</em> mm) and large (5-8 mm) diameter follicles were aspirated and pooled separately for each ovary pair. Groups classified as summer-small (n=8), summer-large (n=15), winter-small (n=9) and winter-large (n=15) were analysed by 1H-NMR spectroscopy. The concentrations of 11 metabolites differed due to follicle size alone (P<0.05), including glucose, lactate, hypoxanthine and five amino acids. The concentrations of all these metabolites, except for glucose, were lower in large FF compared with small FF. Significant interaction effects of follicle size and season were found for the concentrations of glutamate, glycine, N-acetyl groups and uridine. Succinate was the only metabolite that differed in concentration due to season alone (P<0.05). The FF levels of progesterone, <em>androstenedione</em> and oestradiol were correlated with the concentrations of most of the metabolites examined. The results indicate that there is a distinct shift in follicular glucose metabolism as follicles increase in diameter and suggest that follicular cells may be more vulnerable to oxidative stress during the summer months. Our findings demonstrate the power of 1H-NMR spectroscopy to expand our understanding of the dynamic and complex microenvironment of the developing follicle.
Publication
Journal: Journal of Steroid Biochemistry and Molecular Biology
March/26/1991
Abstract
Two transplantable, androgen dependent prostate tumor models of human origin, PC-82 and PC-EW, were used to study the effect of low androgen levels and adrenal androgens on prostate tumor cell proliferation. Tumor load of the PC-82 and PC-EW tumors could be maintained constant when plasma testosterone levels were 0.8 and 0.9 nmol/l, respectively, corresponding with an intratissue 5 alpha-dihydrotestosterone level of 3-<em>4</em> pmol/g tissue. This critical androgen level for prostate tumor growth stimulation amounted to 2-3 times the castration level and proved to be similar for both tumor models. Relatively high levels of <em>androstenedione</em> resulted in physiological levels of plasma testosterone causing androgen concentrations in PC-82 tumor tissue exceeding the critical level for tumor growth. These results indicate that submaximal suppression of androgens can stop tumor growth in these prostate tumor models.
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