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Sample records for androsterone

  1. Morphological characterization of fullerene–androsterone conjugates

    Directory of Open Access Journals (Sweden)

    Alberto Ruiz

    2014-03-01

    Full Text Available Here we report on the self-organization characteristics in water of two diastereomer pairs of fullerene–androsterone hybrids that have the hydrophobic C60 appendage in the A and D ring of the androsterone moiety, respectively. The morphology and particle size in aqueous solution were determined by transmission electron microscopy (TEM and dynamic light scattering (DLS, with satisfactory agreement between both techniques. In general, these fullerene derivatives are shown to organize into spherical nano-scale structures with diameters in the ranges of 10–20 and 30–50 nm, respectively.

  2. 21 CFR 862.1080 - Androsterone test system.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Androsterone test system. 862.1080 Section 862.1080 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Chemistry Test Systems §...

  3. Brain and Serum Androsterone Is Elevated in Response to Stress in Rats with Mild Traumatic Brain Injury.

    Science.gov (United States)

    Servatius, Richard J; Marx, Christine E; Sinha, Swamini; Avcu, Pelin; Kilts, Jason D; Naylor, Jennifer C; Pang, Kevin C H

    2016-01-01

    Exposure to lateral fluid percussion (LFP) injury consistent with mild traumatic brain injury (mTBI) persistently attenuates acoustic startle responses (ASRs) in rats. Here, we examined whether the experience of head trauma affects stress reactivity. Male Sprague-Dawley rats were matched for ASRs and randomly assigned to receive mTBI through LFP or experience a sham surgery (SHAM). ASRs were measured post injury days (PIDs) 1, 3, 7, 14, 21, and 28. To assess neurosteroids, rats received a single 2.0 mA, 0.5 s foot shock on PID 34 (S34), PID 35 (S35), on both days (2S), or the experimental context (CON). Levels of the neurosteroids pregnenolone (PREG), allopregnanolone (ALLO), and androsterone (ANDRO) were determined for the prefrontal cortex, hippocampus, and cerebellum. For 2S rats, repeated blood samples were obtained at 15, 30, and 60 min post-stressor for determination of corticosterone (CORT) levels after stress or context on PID 34. Similar to earlier work, ASRs were severely attenuated in mTBI rats without remission for 28 days after injury. No differences were observed between mTBI and SHAM rats in basal CORT, peak CORT levels or its recovery. In serum and brain, ANDRO levels were the most stress-sensitive. Stress-induced ANDRO elevations were greater than those in mTBI rats. As a positive allosteric modulator of gamma-aminobutyric acid (GABAA) receptors, increased brain ANDRO levels are expected to be anxiolytic. The impact of brain ANDRO elevations in the aftermath of mTBI on coping warrants further elaboration.

  4. Brain and Serum Androsterone is Elevated in Response to Stress in Rats with Mild Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Richard J Servatius

    2016-08-01

    Full Text Available Exposure to lateral fluid percussion (LFP injury consistent with mild traumatic brain injury (mTBI persistently attenuates acoustic startle responses (ASRs in rats. Here, we examined whether the experience of head trauma affects stress reactivity. Male Sprague-Dawley rats were matched for ASRs and randomly assigned to receive mTBI through LFP or experience a sham surgery (SHAM. ASRs were measured post injury days (PIDs 1, 3, 7, 14, 21 and 28. To assess neurosteroids, rats received a single 2.0 mA, 0.5 s foot shock on PID 34 (S34, PID 35 (S35, on both days (2S, or the experimental context (CON. Levels of the neurosteroids pregnenolone (PREG, allopregnanolone (ALLO, and androsterone (ANDRO were determined for the prefrontal cortex, hippocampus and cerebellum. For 2S rats, repeated blood samples were obtained at 15, 30 and 60 min post-stressor for determination of corticosterone (CORT levels after stress or context on PID 34. Similar to earlier work, ASRs were severely attenuated in mTBI rats without remission for 28 days after injury. No differences were observed between mTBI and SHAM rats in basal CORT, peak CORT levels or its recovery. In serum and brain, ANDRO levels were the most stress-sensitive. Stress-induced ANDRO elevations were greater than those in mTBI rats. As a positive allosteric modulator of gamma-aminobutyric acid (GABAA receptors, increased brain ANDRO levels are expected to be anxiolytic. The impact of brain ANDRO elevations in the aftermath of mTBI on coping warrants further elaboration.

  5. The neurosteroid dehydroepiandrosterone sulfate, but not androsterone, enhances the antidepressant effect of cocaine examined in the forced swim test--Possible role of serotonergic neurotransmission.

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    Krzascik, Pawel; Zajda, Malgorzata Elzbieta; Majewska, Maria Dorota

    2015-04-01

    One of the mechanisms of cocaine's actions in the central nervous system is its antidepressant action. This effect might be responsible for increased usage of the drug by individuals with mood disorders. Higher endogenous levels of the excitatory neurosteroid dehydroepiandrosterone sulfate (DHEAS) were reported to correlate with successful abstinence from cocaine use in addicts, but a clinical trial showed that supplementation with a high dose of DHEA increased cocaine usage instead. Such ambiguous effects of DHEA(S) could potentially be linked to its influence on the antidepressant effect of cocaine. In this study we tested DHEAS and its metabolite, androsterone, for interactions with cocaine in animal model of depression (forced swim test) and examined the effects of both steroids and cocaine on serotoninergic neurotransmission. All substances were also tested for influence on locomotor activity. A cocaine dose of 5mg/kg, which had no significant effect on locomotor activity, was chosen for the forced swim test. Neither DHEAS nor androsterone showed any antidepressant action in this test, while cocaine manifested a clear antidepressant effect. Androsterone slightly reduced the antidepressant influence of cocaine while DHEAS markedly, dose-dependently enhanced it. Such an effect might be caused by the influence of DHEAS on serotonin neurotransmission, as this steroid decreased serotonin concentration and turnover in the striatum. When DHEAS and cocaine were administered together, the levels of serotonin in the striatum and hippocampus remained unchanged. This phenomenon may explain the additive antidepressant action of DHEAS and cocaine and why co-administration of DHEAS and cocaine increases drug use.

  6. A theoretical study on the characteristics of the intermolecular interactions in the active site of human androsterone sulphotransferase: DFT calculations of NQR and NMR parameters and QTAIM analysis.

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    Astani, Elahe K; Heshmati, Emran; Chen, Chun-Jung; Hadipour, Nasser L

    2016-07-01

    A theoretical study at the level of density functional theory (DFT) was performed to characterize noncovalent intermolecular interactions, especially hydrogen bond interactions, in the active site of enzyme human androsterone sulphotransferase (SULT2A1/ADT). Geometry optimization, interaction energy, (2)H, (14)N, and (17)O electric field gradient (EFG) tensors, (1)H, (13)C, (17)O, and (15)N chemical shielding (CS) tensors, Natural Bonding Orbital (NBO) analysis, and quantum theory of atoms in molecules (QTAIM) analysis of this active site were investigated. It was found that androsterone (ADT) is able to form hydrogen bonds with residues Ser80, Ile82, and His99 of the active site. The interaction energy calculations and NBO analysis revealed that the ADT molecule forms the strongest hydrogen bond with Ser80. Results revealed that ADT interacts with the other residues through electrostatic and Van der Waals interactions. Results showed that these hydrogen bonds influence on the calculated (2)H, (14)N, and (17)O quadrupole coupling constants (QCCs), as well as (1)H, (13)C, (17)O, and (15)N CS tensors. The magnitude of the QCC and CS changes at each nucleus depends directly on its amount of contribution to the hydrogen bond interaction.

  7. Measuring Faecal Epi-Androsterone as an Indicator of Gonadal Activity in Spotted Hyenas (Crocuta crocuta.

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    Susanne Pribbenow

    Full Text Available Enzyme immunoassays (EIA that measure faecal testosterone metabolites (fTM are useful tools to monitor gonadal activity. The aim of this study was to validate an "in-house" epiandrosterone EIA to monitor fTM in spotted hyenas. FTM were characterised in a male and a female hyena that each received an injection of 3H-testosterone. High-performance liquid chromatography (HPLC analyses revealed a cluster of highly polar enzyme-hydrolysable hormone metabolite conjugates. We performed hydrolysis using β-glucuronidase to deconjugate metabolites and improve sensitivity of the assay. Because β-glucuronidase from Helix pomatia has been reported to bias testosterone measurements in some species, we compared the enzymatic activity of the commonly used β-glucuronidase extracted from H. pomatia with the same enzyme from Escherichia coli. Our results showed that β-glucuronidases from both sources produced similar results from spotted hyena faeces. We therefore hydrolysed samples with H. pomatia enzymes. HPLC analyses also demonstrated that following hydrolysis the epiandrosterone EIA measured significant amounts of immunoreactive metabolites corresponding to radiolabelled metabolites in both sexes. Additionally, HPLC and GC-MS analyses confirmed the presence of epiandrosterone in faeces of spotted hyenas. The biological relevance of the epiandrosterone EIA was validated by demonstrating (1 a significant increase in fTM levels in response to a testosterone injection within 16 h, (2 no biological responsiveness to an adrenocorticotropic hormone (ACTH injection and (3 significant differences in fTM levels between juvenile males and adult immigrant males in a free-ranging wild population. Our results clearly demonstrate that the epiandrosterone EIA is a reliable non-invasive method to monitor gonadal activity in spotted hyenas.

  8. Experimental and Theoretical Investigation of Sodiated Multimers of Steroid Epimers with Ion Mobility-Mass Spectrometry

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    Chouinard, Christopher D.; Cruzeiro, Vinícius Wilian D.; Roitberg, Adrian E.; Yost, Richard A.

    2017-02-01

    Ion mobility-mass spectrometry (IM-MS) has recently seen increased use in the analysis of small molecules, especially in the field of metabolomics, for increased breadth of information and improved separation of isomers. In this study, steroid epimers androsterone and trans-androsterone were analyzed with IM-MS to investigate differences in their relative mobilities. Although sodiated monomers exhibited very similar collision cross-sections (CCS), baseline separation was observed for the sodiated dimer species (RS = 1.81), with measured CCS of 242.6 and 256.3 Å2, respectively. Theoretical modeling was performed to determine the most energetically stable structures of solution-phase and gas-phase monomer and dimer structures. It was revealed that these epimers differ in their preferred dimer binding mode in solution phase: androsterone adopts a R=O - Na+ - OH—R' configuration, whereas trans-androsterone adopts a R=O - Na+ - O=R' configuration. This difference contributes to a significant structural variation, and subsequent CCS calculations based on these structures relaxed in the gas phase were in agreement with experimentally measured values (ΔCCS 5%). Additionally, these calculations accurately predicted the relative difference in mobility between the epimers. This study illustrates the power of combining experimental and theoretical results to better elucidate gas-phase structures.

  9. Effects of thyroid status and thyrostatic drugs on hepatic glucuronidation of lodothyronines and other substrates in rats - Induction of phenol UDP-glucuronyltransferase by methimazole

    NARCIS (Netherlands)

    T.J. Visser (Theo); E. Kaptein (Ellen); A.L. Gijzel (Anthonie); W.W. de Herder (Wouter); M.L. Cannon (Mark); F. Bonthuis (Fred); W.J. de Greef (W.)

    1996-01-01

    textabstractGlucuronidation of iodothyronines in rat liver is catalyzed by at least three UDP-glucuronyltransferases (UGTs): bilirubin UGT, phenol UGT, and androsterone UGT. Bilirubin and phenol UGT activities are regulated by thyroid hormone, but the effect of thyroid status on hepatic glucuronidat

  10. Effect of MK-906, a specific 5 alpha-reductase inhibitor, on serum androgens and androgen conjugates in normal men.

    Science.gov (United States)

    Rittmaster, R S; Stoner, E; Thompson, D L; Nance, D; Lasseter, K C

    1989-01-01

    To determine the hormonal effects of MK-906, an orally active 5 alpha-reductase inhibitor, on serum androgens and androgen conjugates, 12 healthy men were given 10, 20, 50, and 100 mg MK-906 2 weeks apart in randomized order in a 4-period crossover design. Serum testosterone (T), dihydrotestosterone (DHT), androstanediol glucuronide, and androsterone glucuronide were measured before and 24 hours after each dose. The effect of MK-906 on glucuronyl transferase activity, the enzyme responsible for androstanediol glucuronide and androsterone glucuronide formation, was assessed in vitro using rat prostate tissue. Serum T levels were unchanged after all doses. Serum DHT, androstanediol glucuronide, and androsterone glucuronide were suppressed by 70, 40, and 56%, respectively, after the 10-mg dose, and by 82, 52, and 66% after the 100-mg dose (P less than 0.02 for the comparison between the 10 and 100-mg doses for all three steroids), respectively. Baseline serum T and DHT levels were strongly correlated (R = 0.89, P = 0.0002), as were androstanediol glucuronide and androsterone glucuronide levels (R = 0.78, P = 0.003), but there was no correlation between DHT levels and the levels of either conjugated steroid. MK-906 had no effect on glucuronyl transferase activity in vitro. It was concluded that single doses of MK-906 suppress both conjugated and unconjugated 5 alpha-reduced androgens. While all three steroids appeared to be good markers of systemic 5 alpha-reductase inhibition, further research will be needed to determine which steroid best reflects tissue DHT levels in patients receiving these inhibitors.

  11. Pyrolytic formation of polyaromatic hydrocarbons from steroid hormones

    OpenAIRE

    2011-01-01

    Four steroid hormones, namely androsterone, cholesterol, estrone and estradiol, have been pyrolysed at 300, 400 and 500 °C and the pyrolysates from these have been analysed by GC-MS. The results indicate that these formed different products under the pyrolysis and most of them evolved into polycyclic aromatic hydrocarbons during their residence in the pyrolysis chamber at high temperatures. The products from the pyrolysates, at all temperatures, were analysed for similarities and differences ...

  12. Purification and properties of a 3 alpha-hydroxysteroid dehydrogenase of rat liver cytosol and its inhibition by anti-inflammatory drugs.

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    Penning, T M; Mukharji, I; Barrows, S; Talalay, P

    1984-01-01

    An NAD(P)-dependent 3 alpha-hydroxysteroid dehydrogenase (EC 1.1.1.50) was purified to homogeneity from rat liver cytosol, where it is responsible for most if not all of the capacity for the oxidation of androsterone, 1-acenaphthenol and benzenedihydrodiol (trans-1,2-dihydroxycyclohexa-3,5-diene). The dehydrogenase has many properties (substrate specificity, pI, Mr, amino acid composition) in common with the dihydrodiol dehydrogenase (EC 1.3.1.20) purified from the same source [Vogel, Bentley, Platt & Oesch (1980) J. Biol. Chem. 255, 9621-9625]. Since 3 alpha-hydroxysteroids are by far the most efficient substrates, the enzyme is more appropriately designated a 3 alpha-hydroxysteroid dehydrogenase. It also promotes the NAD(P)H-dependent reductions of quinones (e.g. 9,10-phenanthrenequinone, 1,4-benzoquinone), aromatic aldehydes (4-nitrobenzaldehyde) and aromatic ketones (4-nitroacetophenone). The dehydrogenase is not inhibited by dicoumarol, disulfiram, hexobarbital or pyrazole. The mechanism of the powerful inhibition of this enzyme by both non-steroidal and steroidal anti-inflammatory drugs [Penning & Talalay (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 4504-4508] was examined with several substrates. Most non-steroidal anti-inflammatory drugs are competitive inhibitors (e.g. Ki for indomethacin, 0.20 microM for 9,10-phenanthrenequinone reduction at pH 6.0, and 0.835 microM for androsterone oxidation at pH 7.0), except for salicylates, which act non-competitively (e.g. Ki for aspirin, 650 microM for androsterone oxidation). The inhibitory potency of these agents falls sharply as the pH is increased from 6 to 9. Most anti-inflammatory steroids are likewise competitive inhibitors, except for the most potent (betamethasone and dexamethasone), which act non-competitively. The enzyme is inhibited competitively by arachidonic acid and various prostaglandins. PMID:6435601

  13. Determination of the origin of urinary norandrosterone traces by gas chromatography combustion isotope ratio mass spectrometry.

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    Hebestreit, Moritz; Flenker, Ulrich; Fusshöller, Gregor; Geyer, Hans; Güntner, Ute; Mareck, Ute; Piper, Thomas; Thevis, Mario; Ayotte, Christiane; Schänzer, Wilhelm

    2006-09-01

    On the one hand, 19-norandrosterone (NA) is the most abundant metabolite of the synthetic anabolic steroid 19-nortestosterone and related prohormones. On the other hand, small amounts are biosynthesized by pregnant women and further evidence exists for physiological origin of this compound. The World Anti-Doping Agency (WADA) formerly introduced threshold concentrations of 2 or 5 ng of NA per ml of urine to discriminate 19-nortestosterone abuse from biosynthetic origin. Recent findings showed however, that formation of NA resulting in concentrations in the range of the threshold levels might be due to demethylation of androsterone in urine, and the WADA 2006 Prohibited List has defined NA as endogenous steroid. To elucidate the endogenous or exogenous origin of NA, (13)C/(12)C-analysis is the method of choice since synthetic 19-nortestosterone is derived from C(3)-plants by partial synthesis and shows delta(13)C(VPDB)-values of around -28 per thousand. Endogenous steroids are less depleted in (13)C due to a dietary mixture of C(3)- and C(4)-plants. An extensive cleanup based on two high performance liquid chromatography cleanup steps was applied to quality control and doping control samples, which contained NA in concentrations down to 2 ng per ml of urine. (13)C/(12)C-ratios of NA, androsterone and etiocholanolone were measured by gas chromatography/combustion/isotope ratio mass spectrometry. By comparing delta(13)C(VPDB)-values of androsterone as endogenous reference compound with NA, the origin of NA in doping control samples was determined as either endogenous or exogenous.

  14. Marked elevation of adrenal steroids, especially androgens, in saliva of prepubertal autistic children.

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    Majewska, Maria Dorota; Hill, Martin; Urbanowicz, Ewa; Rok-Bujko, Paulina; Bieńkowski, Przemysław; Namysłowska, Irena; Mierzejewski, Paweł

    2014-06-01

    Autism is diagnosed on the basis of behavioral manifestations, but its biomarkers are not well defined. A strong gender bias typifying autism (it is 4-5 times more prevalent in males) suggests involvement of steroid hormones in autism pathobiology. In order to evaluate the potential roles of such hormones in autism, we compared the salivary levels of 22 steroids in prepubertal autistic male and female children from two age groups (3-4 and 7-9 years old) with those in healthy controls. The steroids were analyzed using gas chromatography-mass spectrometry and radioimmunoassay. Statistical analysis (ANOVA) revealed that autistic children had significantly higher salivary concentrations of many steroid hormones (both C21 and C19) than control children. These anomalies were more prominent in older autistic children and in boys. The levels of androgens (androstenediol, dehydroepiandrosterone, androsterone and their polar conjugates) were especially increased, indicative of precocious adrenarche and predictive of early puberty. The concentrations of the steroid precursor, pregnenolone, and of several pregnanolones were also higher in autistic than in healthy children, but cortisol levels were not different. Some steroids, whose levels are raised in autism (allopregnanolone, androsterone, pregnenolone, dehydroepiandrosterone and their sulfate conjugates) are neuroactive and modulate GABA, glutamate, and opioid neurotransmission, affecting brain development and functioning. These steroids may contribute to autism pathobiology and symptoms such as elevated anxiety, sleep disturbances, sensory deficits, and stereotypies among others. We suggest that salivary levels of selected steroids may serve as biomarkers of autism pathology useful for monitoring the progress of therapy.

  15. [Histologic study of stimulation of preputial glands in the mouse by androgens and inhibition by a detergent or zinc salts].

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    Marois, M; Rateau, J C; Elie, C

    1982-12-01

    Preputial glands are a kind of sebaceous glands ; they play a role in reproduction and sexual and social behavior by means of secreted pheromones. In this work, the authors compared the regression of these glands to that of seminal vesicles and investigated the stimulating potency of three androgens : testosterone, androstenedione, androsterone. These data demonstrate the sensitivity of preputial glands to all three androgens. Castration interrupted the secretory activity of the glandular cells of the acini. Four injections of 250 micrograms of testosterone, nine injections of 250 micrograms of androstenedione or androsterone to male mice castrated before puberty restored elaboration and holocrine secretion of sebum. The authors tested for a possible antagonistic action of two substances : a detergent, superinone (100 mg body weight) and zinc salts (10 mg body weight) associated to androgens. After treatment by superinone, histological analysis revealed glandular cell lysis. The action of zinc salts was less pronounced. Zinc acetate and sulfate seem to counter the elaboration of secretions without disrupting glandular structure. The mechanisms of action of their two substances are very probably different.

  16. Evaluation and identification of dioxin exposure biomarkers in human urine by high-resolution metabolomics, multivariate analysis and in vitro synthesis.

    Science.gov (United States)

    Jeanneret, Fabienne; Tonoli, David; Hochstrasser, Denis; Saurat, Jean-Hilaire; Sorg, Olivier; Boccard, Julien; Rudaz, Serge

    2016-01-05

    A previous high-resolution metabolomic study pointed out a dysregulation of urinary steroids and bile acids in human cases of acute dioxin exposure. A subset of 24 compounds was highlighted as putative biomarkers. The aim of the current study was (i) to evaluate the 24 biomarkers in an independent human cohort exposed to dioxins released from the incineration fumes of a municipal waste incinerator and; (ii) to identify them by comparison with authentic chemical standards and biosynthesised products obtained with in vitro metabolic reactions. An orthogonal projection to latent structures discriminant analysis built on biomarker profiles measured in the intoxicated cohort and the controls separated both groups with reported values of 93.8%; 100% and 87.5% for global accuracy; sensitivity and specificity; respectively. These results corroborated the 24 compounds as exposure biomarkers; but a definite identification was necessary for a better understanding of dioxin toxicity. Dehydroepiandrosterone 3β-sulfate, androsterone 3α-glucuronide, androsterone 3α-sulfate, pregnanediol 3α-glucuronide and 11-ketoetiocholanolone 3α-glucuronide were identified by authentic standards. Metabolic reactions characterised four biomarkers: glucuronide conjugates of 11β-hydroxyandrosterone; glycochenodeoxycholic acid and glycocholic acid produced in human liver microsomes and glycoursodeoxycholic acid sulfate generated in cytosol fraction. The combination of metabolomics by high-resolution mass spectrometry with in vitro metabolic syntheses confirmed a perturbed profile of steroids and bile acids in human cases of dioxin exposure.

  17. Tandem mass spectrometry approach for the investigation of the steroidal metabolism: structure-fragmentation relationship (SFR) in anabolic steroids and their metabolites by ESI-MS/MS analysis.

    Science.gov (United States)

    Musharraf, Syed Ghulam; Ali, Arslan; Khan, Naik Tameem; Yousuf, Maria; Choudhary, Muhammad Iqbal; Atta-ur-Rahman

    2013-02-01

    Electrospray ionization tandem mass spectrometry (ESI-MS/MS) was used to investigate the effect of different substitutions introduced during metabolism on fragmentation patterns of four anabolic steroids including methyltestosterone, methandrostenolone, cis-androsterone and adrenosterone, along with their metabolites. Collision-induced dissociation (CID) analysis was performed to correlate the major product ions of 19 steroids with structural features. The analysis is done to portray metabolic alteration, such as incorporation or reduction of double bonds, hydroxylations, and/or oxidation of hydroxyl moieties to keto functional group on steroidal skeleton which leads to drastically changed product ion spectra from the respective classes of steroids, therefore, making them difficult to identify. The comparative ESI-MS/MS study also revealed some characteristic peaks to differentiate different steroidal metabolites and can be useful for the unambiguous identification of anabolic steroids in biological fluid. Moreover, LC-ESI-MS/MS analysis of fermented extract of methyltestosterone, obtained by Macrophomina phaseolina was also investigated.

  18. Skin surface lipid composition, acne, pubertal development, and urinary excretion of testosterone and 17-ketosteroids in children.

    Science.gov (United States)

    Pochi, P E; Strauss, J S; Downing, D T

    1977-11-01

    Fifty-two children, age 5-10, from acne-prone families, were studied for a period of 1 year to examine the interrelationship between sebum, acne, pubertal development, and urinary steroid excretion. In each of the subjects, 30 boys and 22 girls, the composition of forehead skin lipid was determined 4 times yearly by thin-layer chromatography, with measurement of triglycerides, diglycerides, free fatty acids, wax esters, squalene, cholesterol, and cholesterol esters. Twice yearly, examination was made of the presence or absence of acne, pubertal maturation and the 24-hour urinary excretion of testosterone as determined by radioimmunnoassay, and of total 17-ketosteroids, dehydroepiandrosterone, androsterone, and etiocholanolone, as determined by paper chromatography. The relative amount of sebaceous lipids was positively correlated with age of the subjects (wax esters p less than .001, squalene p less than .05), as was the triglyceride-diglyceride component (p less than .05). No significant correlation was seen with the fatty acids. Acne, primarily comedonal, occurred in 27/52 subjects (15 girls, 12 boys) and was associated with higher sebum values. One-half of the children with acne had no signs of pubertal development. A significantly positive correlation was observed between the relative amount of sebaceous lipid and the urinary excretion of 17-ketosteroids, androsterone, and etiocholanolone in both sexes, and of testosterone and dehydroepiandrosterone in boys. The development of acne in children is an early pubertal event, often evident before other signs of pubertal maturation, and it is associated with an increase in sebum and in the urinary excretion of androgenic steroids.

  19. Microbial Baeyer-Villiger oxidation of 5α-steroids using Beauveria bassiana. A stereochemical requirement for the 11α-hydroxylation and the lactonization pathway.

    Science.gov (United States)

    Świzdor, Alina; Panek, Anna; Milecka-Tronina, Natalia

    2014-04-01

    Beauveria bassiana KCH 1065, as was recently demonstrated, is unusual amongst fungal biocatalysts in that it converts C19 3-oxo-4-ene and 3β-hydroxy-5-ene as well as 3β-hydroxy-5α-saturated steroids to 11α-hydroxy ring-D lactones. The Baeyer-Villiger monooxygenase (BVMO) of this strain is distinguished from other enzymes catalyzing BVO of steroidal ketones by the fact that it oxidizes solely substrates with 11α-hydroxyl group. The current study using a series of 5α-saturated steroids (androsterone, 3α-androstanediol and androstanedione) has highlighted that a small change of the steroid structure can result in significant differences of the metabolic fate. It was found that the 3α-stereochemistry of hydroxyl group restricted "normal" binding orientation of the substrate within 11α-hydroxylase and, as a result, androsterone and 3α-androstanediol were converted into a mixture of 7β-, 11α- and 7α-hydroxy derivatives. Hydroxylation of androstanedione occurred only at the 11α-position, indicating that the 3-oxo group limits the alternative binding orientation of the substrate within the hydroxylase. Only androstanedione and 3α-androstanediol were metabolized to hydroxylactones. The study uniquely demonstrated preference for oxidation of equatorial (11α-, 7β-) hydroxyketones by BVMO from B. bassiana. The time course experiments suggested that the activity of 17β-HSD is a factor determining the amount of produced ring-D lactones. The obtained 11α-hydroxylactones underwent further transformations (oxy-red reactions) at C-3. During conversion of androstanedione, a minor dehydrogenation pathway was observed with generation of 11α,17β-dihydroxy-5α-androst-1-en-3-one. The introduction of C1C2 double bond has been recorded in B. bassiana for the first time.

  20. Activation of two mutant androgen receptors from human prostatic carcinoma by adrenal androgens and metabolic derivatives of testosterone.

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    Culig, Z; Stober, J; Gast, A; Peterziel, H; Hobisch, A; Radmayr, C; Hittmair, A; Bartsch, G; Cato, A C; Klocker, H

    1996-01-01

    The androgen receptor (AR) plays a central regulatory role in prostatic carcinoma and is a target of androgen ablation therapy. Recent detection of mutant receptors in tumor specimens suggest a contribution of AR alterations to progression towards androgen independence. In a specimen derived from metastatic prostate cancer we have reported a point mutation in the AR gene that leads to a single amino acid exchange in the ligand binding domain of the receptor. Another amino acid exchange resulting from a point mutation was also identified 15 amino acids away from our mutation. This mutation was detected in the AR gene isolated from an organ-confined prostatic tumor. Here we report the functional characterization of the two mutant receptors in the presence of adrenal androgens and testosterone metabolites. These studies were performed by cotransfecting androgen-responsive reporter genes and either the wild-type or mutant AR expression vectors into receptor negative DU-145 and CV-1 cells. The indicator genes used consisted of the promoter of the androgen-inducible prostate-specific antigen gene or the C' Delta9 enhancer fragment from the promoter of the mouse sex-limited protein driving the expression of the bacterial chloramphenicol acetyl transferase gene. Cotransfection-transactivation assays revealed that the adrenal androgen androstenedione and two products of testosterone metabolism, androsterone and androstandiol, induced reporter gene activity more efficiently in the presence of the mutant receptors than in the presence of the wild-type receptor. No difference between wild-type and mutant receptors was observed in the presence of the metabolite androstandione. The interaction of receptor-hormone complexes with target DNA was studied in vitro by electrophoretic mobility shift assays (EMSA). Dihydrotestosterone and the synthetic androgen mibolerone induced a faster migrating complex with all receptors, whereas the androgen metabolite androstandione induced this

  1. Exposure to phytoestrogens in the perinatal period affects androgen secretion by testicular Leydig cells in the adult rat.

    Science.gov (United States)

    Akingbemi, Benson T; Braden, Tim D; Kemppainen, Barbara W; Hancock, Karen D; Sherrill, Jessica D; Cook, Sarah J; He, Xiaoying; Supko, Jeffrey G

    2007-09-01

    The use of soy-based products in the diet of infants has raised concerns regarding the reproductive toxicity of genistein and daidzein, the predominant isoflavones in soybeans with estrogenic activity. Time-bred Long-Evans dams were fed diets containing 0, 5, 50, 500, or 1000 ppm of soy isoflavones from gestational d 12 until weaning at d 21 postpartum. Male rats in all groups were fed soy-free diets from postnatal d 21 until 90 d of age. The mean +/- SD concentration of unconjugated (i.e. biologically active) genistein and daidzein in serum from the group of dams maintained on the diet containing the highest amount of isoflavones (1000 ppm) were 17 +/- 27 and 56 +/- 30 nM, respectively, at d 21 postpartum. The concentrations were considerably greater in male offspring (genistein: 73 +/- 46 nM; daidzein: 106 +/- 53 nM). Although steroidogenesis was decreased in individual Leydig cells, male rats from the highest exposure group (1000 ppm diet) exhibited elevated serum levels of the sex steroid hormones androsterone at 21 d (control: 15 +/- 1.5 vs.28 +/- 3.5 ng/ml; P phytoestrogen action. Thus, phytoestrogens have the ability to regulate Leydig cells, and additional studies to assess potential adverse effects of dietary soy-based products on reproductive tract development in neonates are warranted.

  2. Rapid determination of natural and synthetic hormones in biosolids and poultry manure by isotope dilution GC-MS/MS.

    Science.gov (United States)

    Albero, Beatriz; Sánchez-Brunete, Consuelo; Miguel, Esther; Aznar, Ramón; Tadeo, José L

    2014-04-01

    The release of hormones into the environment due to land application of biosolids and manure is a cause of concern for their potential impacts. This paper presents the development of a rapid and sensitive method, based on extraction, for the analysis of 13 hormones in biosolids and poultry manure. A simultaneous derivatization of hydroxyl and ketone groups was carried out for the determination of hormones by GC–MS/MS. The method was validated in three matrices (sewage sludge, manure, and broiler litter). Recoveries from spiked samples at three concentration levels (50, 25, and 10 ng/g) ranged from 76 to 124% with relative SDs ≤ 16%. Method detection limits for the three matrices were in the range of 0.5–3.0 ng/g dry weight. The optimized method was applied to biosolid and poultry manure samples collected in Spain. Only seven of the 13 studied hormones were detected in the different samples. trans-Androsterone was detected at high levels (up to 3.1 μg/g in biosolid samples). Estrone and estradiol were the two hormones detected at higher levels in layer manure, whereas estrone and 4-androstene-3,17-dione presented the highest levels in broiler litter.

  3. Occurrence of steroid hormones and antibiotics in shallow groundwater impacted by livestock waste control facilities

    Science.gov (United States)

    Bartelt-Hunt, Shannon; Snow, Daniel D.; Damon-Powell, Teyona; Miesbach, David

    2011-04-01

    Wastewater impoundments at concentrated animal feeding operations (CAFOs) represent a potential source of veterinary pharmaceuticals and steroid hormone contamination to shallow groundwater. This study investigates the occurrence of seventeen veterinary pharmaceuticals and thirteen steroid hormones and hormone metabolites in lagoons and adjacent groundwater at operating swine and beef cattle facilities. These sites were chosen because subsurface geology and previous monitoring of nitrate, ammonia and chloride levels in shallow ground water strongly indicated direct infiltration, and as such represent worst cases for ground water contamination by waste water. Pharmaceutical compounds detected in samples obtained from cattle facilities include sulfamerazine; sulfamethazine; erythromycin; monensin; tiamulin; and sulfathiazole. Lincomycin; ractopamine; sulfamethazine; sulfathiazole; erythromycin; tiamulin and sulfadimethoxine were detected in wastewater samples obtained from swine facilities. Steroid hormones were detected less frequently than veterinary pharmaceuticals in this study. Estrone, testosterone, 4-androstenedione, and androsterone were detected in wastewater impoundments at concentrations ranging from 30 to 3600 ng/L, while only estrone and testosterone were detected in groundwater samples at concentrations up to 390 ng/L. The co-occurrence of veterinary pharmaceutical and steroid hormone contamination in groundwater at these locations and the correlation between pharmaceutical occurrence in lagoon wastewater and hydraulically downgradient groundwater indicates that groundwater underlying some livestock wastewater impoundments is susceptible to contamination by veterinary pharmaceuticals and steroid hormones originating in wastewater lagoons.

  4. Influence of synthetic and natural food dyes on activities of CYP2A6, UGT1A6, and UGT2B7.

    Science.gov (United States)

    Kuno, Nayumi; Mizutani, Takaharu

    2005-08-27

    Synthetic or natural food dyes are typical xenobiotics, as are drugs and pollutants. After ingestion, part of these dyes may be absorbed and metabolized by phase I and II drug-metabolizing enzymes and excreted by transporters of phase III enzymes. However, there is little information regarding the metabolism of these dyes. It was investigated whether these dyes are substrates for CYP2A6 and UDP-glucuronosyltransferase (UGT). The in vitro inhibition of drug-metabolizing enzymes by these dyes was also examined. The synthetic food dyes studied were amaranth (food red no. 2), erythrosine B (food red no. 3), allura red (food red no. 40), new coccine (food red no. 102), acid red (food red no. 106), tartrazine (food Yellow no. 4), sunset yellow FCF (food yellow no. 5), brilliant blue FCF (food blue no. 1), and indigo carmine (food blue no. 2). The natural additive dyes studied were extracts from purple sweet potato, purple corn, cochineal, monascus, grape skin, elderberry, red beet, gardenia, and curthamus. Data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. Only indigo carmine inhibited CYP2A6 in a noncompetitive manner, while erythrosine B inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). In the natural additive dyes just listed, only monascus inhibited UGT1A6 and UGT2B7.

  5. Phytochemicals and the breakthrough of traditional herbs in the management of sexual dysfunctions.

    Science.gov (United States)

    Adimoelja, A

    2000-01-01

    Traditional herbs have been a revolutionary breakthrough in the management of erectile dysfunction and have become known world-wide as an 'instant' treatment. The modern view of the management of erectile dysfunction subscribes to a single etiology, i.e. the mechanism of erection. A large number of pharmacological agents are orally consumed and vasoactive agents inserted intraurethrally or injected intrapenially to regain good erection. Modern phytochemicals have developed from traditional herbs. Phytochemicals focus their mechanism of healing action to the root cause, i.e. the inability to control the proper function of the whole body system. Hence phytochemicals manage erectile dysfunction in the frame of sexual dysfunction as a whole entity. Protodioscin is a phytochemical agent derived from Tribulus terrestris L plant, which has been clinically proven to improve sexual desire and enhance erection via the conversion of protodioscine to DHEA (De-Hydro-Epi-Androsterone). Preliminary observations suggest that Tribulus terrestris L grown on different soils does not consistently produce the active component Protodioscin. Further photochemical studies of many other herbal plants are needed to explain the inconsistent results found with other herbal plants, such as in diversities of Ginseng, Eurycoma longifolia, Pimpinella pruacen, Muara puama, Ginkgo biloba, Yohimbe etc.

  6. Testosterone metabolism of fibroblasts grown from prostatic carcinoma, benign prostatic hyperplasia and skin fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Schweikert, H.U.; Hein, H.J.; Romijn, J.C.; Schroeder, F.H.

    1982-02-01

    The metabolism of (1,2,6,7-3H)testosterone was assessed in fibroblast monolayers derived from tissue of 5 prostates with benign hyperplasia (BPH), 4 prostates with carcinoma (PC), and 3 biopsy samples of skin, 2 nongenital skin (NG) and 1 genital skin. The following metabolites could be identified: androstanedione androstenedione, dihydrotestosterone, androsterone, epiandrosterone, androstane-3 alpha, 17 beta-diol and androstane-3 beta, 17 beta-diol. Testosterone was metabolized much more rapidly in fibroblasts originating from prostatic tissue than in fibroblasts derived from NG. A significantly higher formation of 5 alpha-androstanes and 3 alpha-hydroxysteroids could be observed in fibroblasts from BPH as compared to PC. 17-ketosteroid formation exceeded 5 alpha-androstane formation in BPH, whereas 5 alpha-reduction was the predominant pathway in fibroblasts grown from PC and NG. Since testosterone metabolism in fibroblasts of prostatic origin therefore resembles in many aspects that in whole prostatic tissue, fibroblasts grown from prostatic tissues might be a valuable tool for further investigation of the pathogenesis of human BPH and PC.

  7. Significant increase of salivary testosterone levels after single therapeutic transdermal administration of testosterone: suitability as a potential screening parameter in doping control.

    Science.gov (United States)

    Thieme, Detlef; Rautenberg, Claudia; Grosse, Joachim; Schoenfelder, Martin

    2013-01-01

    The legally defensible proof of the abuse of endogenous steroids in sports is currently based on carbon isotope ratio mass spectrometry (IRMS), i.e. a comparison between (13)C/(12)C ratios of diagnostic precursors and metabolites of testosterone. The application of this technique requires a chromatographic baseline separation of respective steroids prior to IRMS detection and hence laborious sample pre-processing of the urinary steroid extracts including clean up by solid-phase extraction and/or liquid chromatography. Consequently, an efficient pre-selection of suspicious control urine samples is essential for appropriate follow up confirmation by IRMS and effective doping control. Two single transdermal administration studies of testosterone (50 mg Testogel® and Testopatch® at 3.8 mg in 16 h, respectively) were conducted and resulting profiles of salivary testosterone and urinary steroid profiles and corresponding carbon isotope ratios were determined. Conventional doping control markers (testosterone/epitestosterone ratio, threshold concentrations of androsterone, etiocholanolone, or androstanediols) did not approach or exceed critical thresholds. In contrast to these moderate variations, the testosterone concentration in oral fluid increased from basal values (30-142 pg/mg) to peak concentrations above 1000 pg/mg. It is likely that this significant increase in oral fluid is due to a pulsatile elevation of free (protein unbound) circulating testosterone after transdermal administration and may be assumed to represent a more diagnostic marker for transdermal testosterone administration.

  8. Effects of resistance training on testosterone metabolism in younger and older men.

    Science.gov (United States)

    Ahtiainen, Juha P; Nyman, Kai; Huhtaniemi, Ilpo; Parviainen, Tapani; Helste, Mika; Rannikko, Antti; Kraemer, William J; Häkkinen, Keijo

    2015-09-01

    This study investigated the effects of resistance training (RT) on the metabolism of testosterone (T) in younger (n=5, 28±3yrs.) and older (n=8, 70±2yrs.) men. Experimental heavy resistance exercises (5×10RM leg presses) were performed before and after a 12-month of RT. No age differences were found in the production or metabolic clearance rate of T (determined by stable isotope dilution method), skeletal muscle androgen receptor content or serum LH concentrations due to acute or chronic RT. The T production capacity response to gonadotropin stimulation and the concentrations of the urinary T metabolites (androsterone and etiocholanolone) were lower in the older compared to younger men (p<0.05-0.01). This study further showed that RT may have acute effect on T production and clearance rates, while the exercise-induced increases in serum T appeared to be induced by decreased metabolic clearance rate of T. Attenuated T production capacity and urinary excretion of T metabolites in older men may reflect the known reduction in testicular steroidogenesis upon aging. No changes were observed in T metabolism due to RT indicating a homeostatic stability for this hormone in men of different ages.

  9. Increased serum levels of C21 steroids in female patients with multiple sclerosis.

    Science.gov (United States)

    Kanceva, R; Stárka, L; Kancheva, L; Hill, M; Veliková, M; Havrdová, E

    2015-01-01

    Multiple sclerosis (MS) is one of the most common neurological diseases. This neurodegenerative autoimmune disease manifests as inflammatory and demyelinating impairment of the central nervous system (CNS). Although some studies demonstrated associations between altered steroidogenesis and pathophysiology of MS as well as the importance of steroids in the pathophysiology of MS, the knowledge concerning the steroid metabolome in female patients is limited. Hence, 51 steroids and steroid polar conjugates were measured in the serum of 12 women with MS, untreated with steroids and 6 age-corresponding female controls with the use of gas chromatography - mass spectrometry (GC-MS). The data were processed using age adjusted ANCOVA, receiver operating characteristics (ROC) analysis and orthogonal projections to latent structures (OPLS). Our data show higher levels of circulating C21 steroids including steroid modulators of ionotropic type A gamma-aminobutyric acid (GABA A) receptors and glutamate receptors. Furthermore, the levels of GABAergic androsterone and 5-androsten-3beta,7alpha,17beta-triol were also higher in the female MS patients. In conclusion, the data demonstrate higher levels of circulating C21 steroids and their polar conjugates and some bioactive C19 steroids in women with MS, which may influence neuronal activity and affect the balance between neuroprotection and excitotoxicity.

  10. Analytical approach for the determination of steroid profile of humans by gas chromatography isotope ratio mass spectrometry aimed at distinguishing between endogenous and exogenous steroids.

    Science.gov (United States)

    Bulska, Ewa; Gorczyca, Damian; Zalewska, Izabela; Pokrywka, Andrzej; Kwiatkowska, Dorota

    2015-03-15

    The contamination of commonly used supplements by unknown steroids as well as their metabolites (parent compounds) become a challenge for the analytical laboratories. Although the determination of steroids profile is not trivial because of the complex matrix and low concentration of single compound, one of the most difficult current problem is to distinguish, during analytical procedure, endogenous androgens such as testosterone, dehydrotestosterone or dehydroepiandrosterone from their synthetic equivalents. The aim of this work was to develop and validate an analytical procedure for determination of the steroid profile in human urine by gas chromatography-combustion-isotope ratio mass spectrometry (GC/C/IRMS) toward distinguishing between endogenous and exogenous steroids. Beside the optimization of the experimental parameters for gas chromatography separation and mass spectrometry, attention was focused on urine sample preparation. Using an optimized sample preparation protocol it was possible to achieve better chromatographic resolutions and better sensitivity enabling the determination of 5 steroids, androsterone, etiocholanolone, testosterone, 5-androstandiol, 11-hydroxyandrdostane, pregnandiol, with the expanded uncertainty (k=2) below 1‰. This enable to evaluate the significant shift of the δ(13)C/(12)C [‰] values for each of examined steroids (excluding ERC). The analytical protocol described in this work was successfully used for the confirmation of positive founding urine by evaluation T/E ratio after GC/C/IRMS analysis.

  11. Reference ranges for the urinary steroid profile in a Latin-American population.

    Science.gov (United States)

    Martínez-Brito, D; Correa Vidal, M T; de la Torre, X; García-Mir, V; Ledea Lozano, O; Granda Fraga, M

    2013-08-01

    The urinary steroid profile has been used in clinical endocrinology for the early detection of enzyme deficiencies. In the field of doping, its evaluation in urine samples is used to diagnose the abuse of substances prohibited in sport. This profile is influenced by sex, age, exercise, diet, and ethnicity, among others; laboratories own reference ranges might compensate for ethnic differences among population and inter-laboratory biases. This paper shows the reference ranges obtained in the Antidoping Laboratory of Havana for the following steroid profile parameters: ten androgens (testosterone, epitestosterone, androsterone, etiocholanolone, 5α-androstan-3α,17β-diol, 5β-androstan-3α,17β-diol, dehydroepiandrosterone, epiandrosterone, 11β-hydroxyandrosterone and 11β-hydroxyetiocholanolone), three estrogens (estradiol, estriol and estrone), two pregnanes (pregnanediol and pregnanetriol) and two corticosteroids (cortisol and tetrahydrocortisol). The urine samples (male: n = 2454 and female: n = 1181) and data obtained are representative of population from Latin-American countries like Cuba, Venezuela, Mexico, Dominican Republic, Guatemala and Chile. Urine samples were prepared by solid-phase extraction followed by enzymatic hydrolysis and liquid-liquid extraction with an organic solvent in basic conditions. Trimethylsilyl derivatives were analyzed by gas chromatography coupled to mass spectrometry. Reference ranges were established for each sex, allowing the determination of abnormal profiles as a first diagnostic tool for the detection of the abuse of androgenic anabolic steroids. The comparison with the Caucasian population confirms that the urinary steroid profile is influenced by ethnicity.

  12. Urinary excretion rates of natural estrogens and androgens from humans, and their occurrence and fate in the environment: a review.

    Science.gov (United States)

    Liu, Ze-Hua; Kanjo, Yoshinori; Mizutani, Satoshi

    2009-09-01

    Endocrine disrupting compounds (EDCs) are pollutants with estrogenic or androgenic activities at very low concentrations and are emerging as a major concern for water quality. For sewage of municipal wastewater treatment plants in cities, one of the most important sources of EDCs are natural estrogens and natural androgens (NEAs) excreted from humans. Therefore, estrogenic/androgenic potencies or relative binding affinity of the NEAs were first outlined from different sources, and data of urinary excretion rates of NEAs were summarized. To evaluate their estrogenic activities, their excretion rates of estrogen equivalent (EEQ) or testosterone (T) equivalent (TEQ) were also calculated. Based on our summary, the total excretion rates of EEQ by estrone (E1), 17beta-estradiol (E2), and estriol (E3) only accounted for 66-82% of the total excretion rate of EEQ among four different groups, and the other corresponding natural estrogens contributed 18-34%, which meant that some of the other natural estrogens may also exist in wastewater with high estrogenic activities. Based on the contribution ratio of individual androgens to the total excretion rate of TEQ, five out of 12 natural androgens, T, dihydrotestosterone (DHT), androsterone (AD), 5beta-androstanediol (beta-ADL), and androstenediol (ANL) were evaluated as the priority natural androgens, which may exist in wastewater with high androgenic activities. Published data on occurrence and fate of the NEAs including natural estrogen conjugates in the environment were also summarized here.

  13. A comprehensive procedure based on gas chromatography-isotope ratio mass spectrometry following high performance liquid chromatography purification for the analysis of underivatized testosterone and its analogues in human urine

    Energy Technology Data Exchange (ETDEWEB)

    Torre, Xavier de la, E-mail: xavier.delatorre@gmail.com [Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197 Rome (Italy); Colamonici, Cristiana; Curcio, Davide; Molaioni, Francesco [Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197 Rome (Italy); Botre, Francesco [Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197 Rome (Italy); Dipartimento di Management, ' Sapienza' Universita di Roma, Via del Castro Laurenziano 9, 00161 Rome (Italy)

    2012-12-05

    Highlights: Black-Right-Pointing-Pointer Overall approach for urine samples purification by HPLC for subsequent GC/C/IRMS analysis in doping control. Black-Right-Pointing-Pointer Detection of pseudo-endogenous androgenic steroids (i.e. testosterone, androstenedione) misuse in sports. Black-Right-Pointing-Pointer Routine analysis of steroids by GC/C/IRMS in sports drug testing. - Abstract: The confirmation by GC/C/IRMS of the exogenous origin of pseudo-endogenous steroids from human urine samples requires extracts of adequate purity. A strategy based on HPLC sample purification prior to the GC/C/IRMS analysis of human urinary endogenous androgens (i.e. testosterone, androsterone and/or androstenediols), is presented. A method without any additional derivatization step is proposed, allowing to simplify the urine pretreatment procedure, leading to extracts free of interferences permitting precise and accurate IRMS analysis, without the need of correcting the measured delta values for the contribution of the derivatizing agent. The HPLC extracts were adequately combined to both reduce the number of GC/C/IRMS runs and to have appropriate endogenous reference compounds (ERC; i.e. pregnanediol, 11-keto-etiocholanolone) on each GC-IRMS run. The purity of the extracts was assessed by their parallel analysis by gas chromatography coupled to mass spectrometry, with GC conditions identical to those of the GC/C/IRMS assay. The method has been validated according to ISO17025 requirements (within assay precision below 0.3 Per-Mille-Sign {sup 13}C delta units and between assay precision below 0.6 Per-Mille-Sign {sup 13}C delta units for most of the compounds investigated) fulfilling the World Anti-Doping Agency requirements.

  14. Identification of metabolites with anticancer properties by computational metabolomics

    Directory of Open Access Journals (Sweden)

    Bowen Nathan J

    2008-06-01

    Full Text Available Abstract Background Certain endogenous metabolites can influence the rate of cancer cell growth. For example, diacylglycerol, ceramides and sphingosine, NAD+ and arginine exert this effect by acting as signaling molecules, while carrying out other important cellular functions. Metabolites can also be involved in the control of cell proliferation by directly regulating gene expression in ways that are signaling pathway-independent, e.g. by direct activation of transcription factors or by inducing epigenetic processes. The fact that metabolites can affect the cancer process on so many levels suggests that the change in concentration of some metabolites that occurs in cancer cells could have an active role in the progress of the disease. Results CoMet, a fully automated Computational Metabolomics method to predict changes in metabolite levels in cancer cells compared to normal references has been developed and applied to Jurkat T leukemia cells with the goal of testing the following hypothesis: Up or down regulation in cancer cells of the expression of genes encoding for metabolic enzymes leads to changes in intracellular metabolite concentrations that contribute to disease progression. All nine metabolites predicted to be lowered in Jurkat cells with respect to lymphoblasts that were examined (riboflavin, tryptamine, 3-sulfino-L-alanine, menaquinone, dehydroepiandrosterone, α-hydroxystearic acid, hydroxyacetone, seleno-L-methionine and 5,6-dimethylbenzimidazole, exhibited antiproliferative activity that has not been reported before, while only two (bilirubin and androsterone of the eleven tested metabolites predicted to be increased or unchanged in Jurkat cells displayed significant antiproliferative activity. Conclusion These results: a demonstrate that CoMet is a valuable method to identify potential compounds for experimental validation, b indicate that cancer cell metabolism may be regulated to reduce the intracellular concentration of

  15. Hormones, sterols, and fecal indicator bacteria in groundwater, soil, and subsurface drainage following a high single application of municipal biosolids to a field.

    Science.gov (United States)

    Gottschall, N; Topp, E; Edwards, M; Payne, M; Kleywegt, S; Russell, P; Lapen, D R

    2013-04-01

    A land application of dewatered municipal biosolids (DMB) was conducted on an agricultural field in fall 2008 at a rate of 22Mg dry weight (dw) ha(-1). Pre- and post- application, hormone, sterol and fecal indicator bacteria concentrations were measured in tile drainage water, groundwater (2, 4, 6m depth), surface soil cores, and DMB aggregates incorporated in the soil (∼0.2m depth) for a period of roughly 1year post-application. Hormones and sterols were detected up to 1year post-application in soil and in DMB aggregates. Hormone (androsterone, desogestrel, estrone) contamination was detected briefly in tile water samples (22d and ∼2months post-app), at lowngL(-1) concentrations (2-34ngL(-1)). Hormones were not detected in groundwater. Sterols were detected in tile water throughout the study period post-application, and multiple fecal sterol ratios suggested biosolids as the source. Coprostanol concentrations in tile water peaked at >1000ngL(-1) (22d post-app) and were still >100ngL(-1) at 6months post-application. Fecal indicator bacteria were detected throughout the study period in tile water, groundwater (⩽2m depth), soil and DMB aggregate samples. These bacteria were strongly linearly related to coprostanol in tile water (R(2)>0.92, phormones and sterols to tile drainage networks may be attributed to a combination of the hydrophobicity of these compounds and limited macroporosity of the field soil. This transitory contamination from hormones and sterols is unlikely to result in any significant pulse exposure risk in subsurface drainage and groundwater.

  16. Sports drug testing: Analytical aspects of selected cases of suspected, purported, and proven urine manipulation.

    Science.gov (United States)

    Thevis, Mario; Geyer, Hans; Sigmund, Gerd; Schänzer, Wilhelm

    2012-01-01

    Manipulation of urine specimens provided by elite athletes for doping control purposes has been reported several times in the past, and in most of these cases urine substitution was eventually proven. Recent findings of suspected and substantiated manipulation have outlined the complexity and diversity of tampering options, sample appearance alterations resulting from non-manipulative influence, and the analytical challenges arising from these scenarios. Using state-of-the-art mass spectrometric and immunological doping control and forensic chemistry methodologies, four unusual findings were observed. One sports drug testing specimen was found to contain an unusually high content of saccharides accompanied by hordenine and Serpine-Z4, while no endogenous steroid (e.g. testosterone, epitestosterone, androsterone and etiocholanolone) was detected. This specimen was identified as non-alcoholic beer filled into the doping control sample container, constituting an undisputed doping offense. A doping control sample of bright green color was received and found to contain residues of methylene blue, which is not considered relevant for doping controls as no masking or manipulative effect is known. In addition, the number of urine samples of raspberry to crimson red coloration received at doping control laboratories has constantly increased during the last years, attributed to the presence of hemoglobin or betanin/isobetanin. Also here, no doping rule violation was given and an impact on routine analytical results was not observed. Finally, a total of 8 sports drug testing samples collected at different competition sites was shown to contain identical urine specimens as indicated by steroid profile analysis and conclusively proven by DNA-STR (short tandem repeat) analysis. Here, the athletes in question were not involved in the urine substitution act but the doping control officer was convicted of sample manipulation.

  17. Skin of the male African catfish, Clarias gariepinus: a source of steroid glucuronides

    Energy Technology Data Exchange (ETDEWEB)

    Ali, S.A.; Schoonen, W.G.; Lambert, J.G.; Van den Hurk, R.; Van Oordt, P.G.

    1987-06-01

    Steroid metabolism in the skin of mature male African catfish, Clarias gariepinus, reared in the laboratory, was studied in vitro by tissue incubations with (/sup 3/H)pregnenolone, (/sup 3/H)dehydroepiandrosterone, (/sup 3/H)17 alpha-hydroxyprogesterone, (/sup 3/H)androstenedione, (/sup 14/C)11 beta-hydroxyandrostenedione, and (/sup 3/H)testosterone as precursors. While pregnenolone was not converted to any other steroid, dehydroepiandrosterone was transformed mainly to 5-androstene-3 beta, 17 beta-diol. The products of 17 alpha-hydroxyprogesterone incubations were 5 beta-pregnane-3 alpha,17 alpha-diol-20-one, 5 beta-pregnane-3 alpha,17 alpha, 20 beta-triol, and 5 beta-pregnan-17 alpha-o1-3,20-dione. The major steroids of androstenedione incubations were etiocholanolone, testosterone, and androsterone. Testosterone was converted mainly to etiocholanolone and androstenedione, and only small quantities of 11 beta-hydroxytestosterone, 11-ketotestosterone, and 11-ketoandrostenedione were the metabolites found in 11 beta-hydroxyandrostenedione incubation. These results demonstrated the presence of the enzymes 5 alpha- and 5 beta-reductases and 3 alpha-, 11 beta-, 17 beta-, and 20 beta-hydroxysteroid dehydrogenases in the skin. From enzymehistochemical results it appeared that the steroid conversions take place in the epithelial cells. Moreover, the presence of UDP-glucose dehydrogenase, an enzyme involved in the synthesis of glucuronic acid, in these cells indicates the possibility of steroid glucuronide formation. Indeed significant amounts of water-soluble steroid conjugates, particularly 5 beta-dihydrotestosterone- and testosterone-glucuronide, were found in the incubations with androstenedione and testosterone, indicating the presence of the UDP-glucuronosyl transferase in the catfish skin.

  18. Intranasal delivery of Natesto® testosterone gel and its effects on doping markers.

    Science.gov (United States)

    Miller, Geoffrey D; Nair, Vinod; Morrison, M Scott; Summers, Maggie; Willick, Stuart E; Eichner, Daniel

    2016-11-01

    The laboratory profile of intranasal testosterone gel has not been previously reported from an anti-doping perspective. Because intranasal testosterone gel is newly available as a commercial product, we sought to examine the laboratory parameters following administration of this formulation, with particular attention to anti-doping guidelines. Five healthy and active male subjects were administered testosterone intranasal gel three times daily for four weeks, using a pattern of five consecutive days on, two days off. Urine was collected after each five-day round of drug administration and analyzed using a full steroid screen and isotope ratio mass spectrometry (IRMS). Windows of detection for elevated testosterone/epitestosterone (T/E) and other steroid ratios, World Anti-Doping Agency (WADA) athlete biological passport (ABP) findings, and IRMS results were analyzed in this study. In the 0-24 h window post-administration, 70% of samples were flagged with a suspicious steroid profile and 85% were flagged as atypical passport findings according to the WADA ABP steroid module. In the 24-48 h window, 0% of samples displayed suspicious steroid profiles while 40% resulted in atypical passport findings. IRMS testing confirmed the presence of exogenous testosterone in 90% and 40% of samples in the 0-24 h and 24-48 h windows post-administration, respectively. Additionally, IRMS data were analyzed to determine commonalities in the population changes in δ(13) C values of testosterone, androsterone, etiocholanolone, 5αAdiol, and 5βAdiol. Though no discernible metabolic trend of the route of administration was identified, we discovered that intranasal gel testosterone is detectable using conventional anti-doping tests. Copyright © 2016 John Wiley & Sons, Ltd.

  19. Traditional Chinese medicine and sports drug testing: identification of natural steroid administration in doping control urine samples resulting from musk (pod) extracts.

    Science.gov (United States)

    Thevis, Mario; Schänzer, Wilhelm; Geyer, Hans; Thieme, Detlef; Grosse, Joachim; Rautenberg, Claudia; Flenker, Ulrich; Beuck, Simon; Thomas, Andreas; Holland, Ruben; Dvorak, Jiri

    2013-01-01

    The administration of musk extract, that is, ingredients obtained by extraction of the liquid secreted from the preputial gland or resulting grains of the male musk deer (eg, Moschus moschiferus), has been recommended in Traditional Chinese Medicine (TCM) applications and was listed in the Japanese pharmacopoeia for various indications requiring cardiovascular stimulation, anti-inflammatory medication or androgenic hormone therapy. Numerous steroidal components including cholesterol, 5α-androstane-3,17-dione, 5β-androstane-3,17-dione, androsterone, etiocholanolone, epiandrosterone, 3β-hydroxy-androst-5-en-17-one, androst-4-ene-3,17-dione and the corresponding urea adduct 3α-ureido-androst-4-en-17-one were characterised as natural ingredients of musk over several decades, implicating an issue concerning doping controls if used for the treatment of elite athletes. In the present study, the impact of musk extract administration on sports drug testing results of five females competing in an international sporting event is reported. In the course of routine doping controls, adverse analytical findings concerning the athletes' steroid profile, corroborated by isotope-ratio mass spectrometry (IRMS) data, were obtained. The athletes' medical advisors admitted the prescription of TCM-based musk pod preparations and provided musk pod samples for comparison purposes to clarify the antidoping rule violation. Steroid profiles, IRMS results, literature data and a musk sample obtained from a living musk deer of a local zoo conclusively demonstrated the use of musk pod extracts in all cases which, however, represented a doping offence as prohibited anabolic-androgenic steroids were administered.

  20. Inactivation by UDP-glucuronosyltransferase enzymes: the end of androgen signaling.

    Science.gov (United States)

    Chouinard, Sarah; Yueh, Mei-Fei; Tukey, Robert H; Giton, Frank; Fiet, Jean; Pelletier, Georges; Barbier, Olivier; Bélanger, Alain

    2008-04-01

    Conjugation by UDP-Glucuronosyltransferase (UGT) is the major pathway of androgen metabolism and elimination in the human. High concentrations of glucuronide conjugates of androsterone (ADT) and androstane-3alpha,17beta-diol (3alpha-diol) are present in circulation and several studies over the last 30 years have concluded that the serum levels of these metabolites might reflect the androgen metabolism in several tissues, including the liver and androgen target tissues. Three UGT2B enzymes are responsible for the conjugation of DHT and its metabolites ADT and 3alpha-diol: UGT2B7, B15 and B17. UGT2B7 is expressed in the liver and skin whereas UGT2B15 and B17 were found in the liver, prostate and skin. Very specific antibodies against each UGT2B enzyme have been obtained and used for immunohistochemical studies in the human prostate. It was shown that UGT2B17 is expressed in basal cells whereas UGT2B15 is only localized in luminal cells, where it inactivates DHT. By using LNCaP cells, we have also demonstrated that the expression and activity of UGT2B15 and B17 are modulated by several endogenous prostate factors including androgen. Finally, to study the physiological role of UGT2B enzymes, transgenic mice bearing the human UGT2B15 gene were recently obtained. A decrease in reproductive tissue weight from transgenic animals compared to those from control animals was observed. In conclusion, the conjugation by UGT2B7, B15 and B17, which represents a non-reversible step in androgen metabolism, is an important means by which androgens are regulated locally. It is also postulated that UGT enzymes protect the tissue from deleteriously high concentrations of active androgen.

  1. Quantification of the adrenal cortex hormones with radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Badillo A, V.; Carrera D, A. A.; Ibarra M, C. M., E-mail: vbadillocren@hotmail.co [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Calle Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2010-10-15

    The pathologies of the adrenal cortex -adrenal insufficiency and Cushing syndrome- have their origin on the deficit or hypersecretion of some of the hormones that are secreted by the adrenal cortex, which is divided in three zones anatomically defined: the external zone, also called the zona glomerulosa, which is the main production site of aldosterone and mineralocorticoids; the internal zone, or zona reticularis, that produces androgens; and the external zone, or zone 1 orticotrop, which is responsible for producing glucocorticoids. In this work, a quantitative analysis of those hormones and their pathologic trigger was made; the quantification was made in the laboratory by means of highly sensitive and specific techniques, in this case, the radioimmunoassay, in which a radioisotope I-125 is used. This technique is based on the biochemical bond-type reaction, because it requires of a substance called the linker, which bonds to another called ligand. This reaction is also known as antigen-antibody (Ag-Ab), where the results of the reaction will depend on the quantity of antigen in the sample and on its affinity for the antibody. In this work, a 56 patients (of which 13 were men and 43 women) study was made. The cortisol, the ACTH, the androsterone and the DHEA values were very elevated in the majority of the cases corresponding to women, predominating cortisol; while in men, a notorious elevation of the 17 {alpha}-OH-PRG and of the DHEA-SO{sub 4} was observed. Based on that, we can conclude that 51 of them did not have mayor complications, because they just went to the laboratory once, while the remaining 5 had a medical monitoring, and they visited the laboratory more than one occasion, tell about a difficulty on their improvement. According to the results, an approximate relation of 8:2 women:men, respectively, becomes clear to the hormonal pathologies of the adrenal cortex. (Author)

  2. [New method for the determination of estrogen and progesterone receptors in human breast cell lines].

    Science.gov (United States)

    Olea, N; Devleeschower, N; Leclercq, G

    1985-12-01

    A method for the determination of estrogen and progesterone receptor levels in human mammary cell lines (MCF-7, Cama-1, ZR-75-1, Evsa-T and HBL-100) is described. Cells cultured as monolayers were incubated with the tritiated steroids, [3H]-17 beta-Estradiol or [3H] ORG-2058. Binding of steroids to receptors was a function of cellular uptake. Incubation periods of 50 min were sufficient to attain maximum intracellular incorporation. The binding of 17 beta-E2 and ORG-2058 to MCF-7 cells, a phenomenon which is saturable at low concentrations for the radioactive ligand, is a linear function of the number of cells assayed (Interval: 2.5 X 10(4) to 1.5 X 10(6) cells per well). Binding data and their Scatchard plot allowed for the calculation of affinity and capacity values. Thus, for ER, Kd = 2.0 +/- 0.5 X 10(-10) M and n = 3.76 +/- 0.91 Fmol/microgram DNA, and for PgR Kd = 2.0 +/- 0.2 X 10(-10) M and n = 14.02 +/- 2.30 Fmol/microgram DNA (Mean +/- SD). Binding specificity of 17 beta-Estradiol and ORG-2058 to MCF-7 cells was analysed by means of study on the inhibitory effect of increasing concentrations of unlabelled competitors: 17 beta-Estradiol, ORG-2058, Estrone, DES, R-5020, Cortisol, Androsterone and Testosterone. Only pharmacological doses of some of the mentioned molecules produce displacement of the hormonereceptor binding. This phenomenon appears to be related to the affinity of these chemical compounds for the receptor macromolecules to which estrogens and progesterone bind.

  3. Profile and removal of endocrine disrupting chemicals by using an ER/AR competitive ligand binding assay and chemical analyses

    Institute of Scientific and Technical Information of China (English)

    Ze-hua Liu; Mamoru Ito; Yoshinori Kanjo; Atsushi Yamamoto

    2009-01-01

    An estrogen receptor (ER)/androgen receptor (AR) ligand competitive binding assay (ER/AR-binding assay) and chemical analyses were used to evaluate the endocrine disrupting chemicals (EDCs) behavior of two municipal wastewater treatment plants (WWTPs) (K and S). In the influents, estrone (El), androsterone (A), androstenedione (AD), BPA (bisphenol A), NP (nonylphenol) and daidzein (DZ) were detected in high amounts with subsequent 24 h-average concentrations of 350, 1000, 29, 1300, 3900, and 5700 ng/L in K-WWTP and of 310, 620, 59, 1600, 2600, and 8400 ng/L in S-WWTP. The estrogenic (androgenic) activity as 17β-estradiol (E2) equivalents (EEQ) or testosterone (Te) equivalents (TEQ) was consequently 620 ng E2/L (570 ng Te/L) and 580 ng E2/L (800 ng Te/L) for the two WWTPs. The removal efficiencies of the above mentioned sole target chemicals were 51%-100% for K-WWTP and 55.6%,100% for S-WWTP. The removal efficiencies of EEQ were about 73% for both WWTPs, while the removal efficiencies of TEQ were 62.1% for K-WWTP and 98.4% for S-WWTP. In addition, chemical-derived EEQ were about 1.2%-52.4% of those by ER-binding assay for K-WWTP and the corresponding ratios were 1.3%-83.3% for S-WWTP, while chemical derived TEQ were less than 3% of values measured by the AR-binding assay for both WWTPs.

  4. Influences of β-HCG administration on carbon isotope ratios of endogenous urinary steroids.

    Science.gov (United States)

    Piper, Thomas; Baume, Norbert; Strahm, Emanuel; Emery, Caroline; Saugy, Martial

    2012-05-01

    Several factors influencing the carbon isotope ratios (CIR) of endogenous urinary steroids have been identified in recent years. One of these should be the metabolism of steroids inside the body involving numerous different enzymes. A detailed look at this metabolism taking into account differences found between steroids excreted as glucuronides or as sulphates and hydrogen isotope ratios of different steroids pointed out possibility of unequal CIR at the main production sites inside the male body - the testes and the adrenal glands. By administration of β-HCG it is possible to strongly stimulate the steroid production within the testes without influencing the production at the adrenal glands. Therefore, this treatment should result in changed CIR of urinary androgens in contrast to the undisturbed pre-treatment values. Four male volunteers received three injections of β-HCG over a time course of 5 days and collected their urine samples at defined intervals after the last administration. Those samples showing the largest response in contrast to the pre-administration urines were identified by steroid profile measurements and subsequent analysed by GC/C/IRMS. CIR of androsterone, etiocholanolone, testosterone, 5α- and 5β-androstanediol and pregnanediol were compared. While pregnanediol was not influenced, most of the investigated androgens showed depleted values after treatment. The majority of differences were found to be statistically significant and nearly all showed the expected trend towards more depleted δ(13)C-values. These results support the hypothesis of different CIR at different production sites inside the human body. The impact of these findings on doping control analysis will be discussed.

  5. Profiling of urinary steroids by gas chromatography-mass spectrometry detection and confirmation of androstenedione administration using isotope ratio mass spectrometry.

    Science.gov (United States)

    Wang, Jingzhu; Wu, Moutian; Liu, Xin; Xu, Youxuan

    2011-12-20

    Androstenedione (4-androstene-3,17-dione) is banned by the World Anti-Doping Agency (WADA) as an endogenous steroid. The official method to confirm androstenedione abuse is isotope ratio mass spectrometry (IRMS). According to the guidance published by WADA, atypical steroid profiles are required to trigger IRMS analysis. However, in some situations, steroid profile parameters are not effective enough to suspect the misuse of endogenous steroids. The aim of this study was to investigate the atypical steroid profile induced by androstenedione administration and the detection of androstenedione doping using IRMS. Ingestion of androstenedione resulted in changes in urinary steroid profile, including increased concentrations of androsterone (An), etiocholanolone (Etio), 5α-androstane-3α,17β-diol (5α-diol), and 5β-androstane-3α,17β-diol (5β-diol) in all of the subjects. Nevertheless, the testosterone/epitestosterone (T/E) ratio was elevated only in some of the subjects. The rapid increases in the concentrations of An and Etio, as well as in T/E ratio for some subjects could provide indicators for initiating IRMS analysis only for a short time period, 2-22h post-administration. However, IRMS could provide positive determinations for up to 55h post-administration. This study demonstrated that, 5β-diol concentration or Etio/An ratio could be utilized as useful indicators for initiating IRMS analysis during 2-36h post-administration. Lastly, Etio, with slower clearance, could be more effectively used than An for the confirmation of androstenedione doping using IRMS.

  6. External calibration in gas chromatography-combustion-isotope ratio mass spectrometry measurements of endogenous androgenic anabolic steroids in sports doping control.

    Science.gov (United States)

    Kioussi, Maroula K; Angelis, Yiannis S; Cawley, Adam T; Koupparis, Michalis; Kazlauskas, Rymantas; Brenna, J Thomas; Georgakopoulos, Costas G

    2011-08-19

    An alternative calibration procedure for the gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) measurements of the World Antidoping Agency (WADA) Accredited Laboratories is presented. To alleviate the need for externally calibrated CO₂ gas for GC-C-IRMS analysis of urinary steroid metabolites, calibration using an external standard mixture solution of steroids with certified isotopic composition was investigated. The reference steroids of the calibration mixture and routine samples underwent identical instrumental processes. The calibration standards bracketed the entire range of the relevant δ¹³C values for the endogenous and exogenous steroids as well as their chromatographic retention times. The certified δ¹³C values of the reference calibrators were plotted in relation to measured m/z ¹³CO₂/¹²CO₂ (i.e. R(45/44)) mass spectrometric signals of each calibrator. δ¹³C values of the sample steroids were calculated from the least squares fit through the calibration curve. The effect of the external calibration on δ¹³C values, using the same calibration standards and set of urine samples but different brands of GC-C-IRMS instruments, was assessed by an interlaboratory study in the WADA Accredited Laboratories of Sydney, Australia and Athens, Greece. Relative correspondence between the laboratories for determination of androsterone, etiocholanolone, 5β-androstane-3α,17β-diacetate, and pregnanediacetate means were SD(δ¹³C)=0.12‰, 0.58‰, -0.34‰, and -0.40‰, respectively. These data demonstrate that accurate intralaboratory external calibration with certified steroids provided by United States Antidoping Agency (USADA) and without external CO₂ calibration is feasible and directly applicable to the WADA Accredited Laboratories for the harmonization of the GC-C-IRMS measurements.

  7. Investigations on hydrogen isotope ratios of endogenous urinary steroids: reference-population-based thresholds and proof-of-concept.

    Science.gov (United States)

    Piper, Thomas; Thomas, Andreas; Thevis, Mario; Saugy, Martial

    2012-09-01

    Carbon isotope ratio (CIR) analysis has been routinely and successfully used in sports drug testing for many years to uncover the misuse of endogenous steroids. One limitation of the method is the availability of steroid preparations exhibiting CIRs equal to endogenous steroids. To overcome this problem, hydrogen isotope ratios (HIR) of endogenous urinary steroids were investigated as a potential complement; results obtained from a reference population of 67 individuals are presented herein. An established sample preparation method was modified and improved to enable separate measurements of each analyte of interest where possible. From the fraction of glucuronidated steroids; pregnanediol, 16-androstenol, 11-ketoetiocholanolone, androsterone (A), etiocholanolone (E), dehydroepiandrosterone (D), 5α- and 5β-androstanediol, testosterone and epitestosterone were included. In addition, sulfate conjugates of A, E, D, epiandrosterone and 17α- and 17β-androstenediol were considered and analyzed after acidic solvolysis. The obtained results enabled the calculation of the first reference-population-based thresholds for HIR of urinary steroids that can readily be applied to routine doping control samples. Proof-of-concept was accomplished by investigating urine specimens collected after a single oral application of testosterone-undecanoate. The HIR of most testosterone metabolites were found to be significantly influenced by the exogenous steroid beyond the established threshold values. Additionally, one regular doping control sample with an extraordinary testosterone/epitestosterone ratio of 100 without suspicious CIR was subjected to the complementary methodology of HIR analysis. The HIR data eventually provided evidence for the exogenous origin of urinary testosterone metabolites. Despite further investigations on HIR being advisable to corroborate the presented reference-population-based thresholds, the developed method proved to be a new tool supporting modern

  8. Doping-control analysis of the 5alpha-reductase inhibitor finasteride: determination of its influence on urinary steroid profiles and detection of its major urinary metabolite.

    Science.gov (United States)

    Thevis, Mario; Geyer, Hans; Mareck, Ute; Flenker, Ulrich; Schänzer, Wilhelm

    2007-04-01

    5alpha-Reductase inhibitors such as finasteride are prohibited in sports according to the World Anti-Doping Agency. This class of drugs is used therapeutically to treat benign prostatic hyperplasia, as well as male baldness, by decreasing 5alpha-reductase activity. Accordingly, metabolic pathways of endogenous as well as synthetic steroids are influenced, which complicates the evaluation of steroid profiles in sports drug testing. The possibility of manipulating steroid excretion profiles and, presumably, to mask steroid abuse was investigated in 5 administration studies with use of finasteride at different doses, with and without coadministration of 19-norandrostenedione. The evaluation of urinary steroid profiles demonstrated the intense effect of finasteride on numerous crucial analytical parameters, in particular the production of 5alpha-steroids such as androsterone and 5alpha-androstane-3alpha,17beta-diol, which was significantly reduced. In addition, the excretion of the main metabolite of norandrostenedione, norandrosterone, was significantly suppressed, by up to 84%, in elimination studies. For doping-control analysis the use of 5alpha-reductase inhibitors causes considerable problems because steroid profile parameters, which are commonly considered stable, are highly affected and complicate the detection of steroid abuse. In addition, the suppression of production and renal excretion of 5alpha-steroids such as 19-norandrosterone generated from anabolic agents such as 19-norandrostenedione may lead to false-negative doping-control results, because urine specimens are reported positive only when a threshold level of 2 ng/mL is exceeded. Finally, a method for the determination of the major urinary metabolite of finasteride (carboxy-finasteride) in routine doping-control screening with use of liquid chromatography-tandem mass spectrometry is described, allowing the detection of carboxy-finasteride for up to 94 hours in urine specimens collected after an oral

  9. Systematic comparison of δ13C measurements of testosterone and derivative steroids in a freeze-dried urine candidate reference material for sports drug testing by gas chromatography/combustion/isotope ratio mass spectrometry and uncertainty evaluation using four different metrological approaches.

    Science.gov (United States)

    Munton, Ellaine; Murby, John; Hibbert, D Brynn; Santamaria-Fernandez, Rebeca

    2011-06-15

    An alternative calibration procedure for use when performing carbon isotope ratio measurements by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) has been developed. This calibration procedure does not rely on the corrections in-built in the instrument software, as the carbon isotope ratios of a sample are calculated from the measured raw peak areas. The method was developed for the certification of a urine reference material for sports drug testing, as the estimation of measurement uncertainty is greatly simplified. To ensure that the method is free from bias arising from the choice of calibration material and instrument, the carbon isotope ratios of steroids in urine extracts were measured using two different instruments in different laboratories, and three different reference materials (CU/USADA steroid standards from Brenna Laboratory, Cornell University; NIST RM8539 mineral oil; methane calibrated against NIST RM8560 natural gas). The measurements were performed at LGC and the Australian National Measurement Institute (NMI). It was found that there was no significant difference in measurement results when different instruments and reference materials were used to measure the carbon isotope ratio of the major testosterone metabolites androsterone and etiocholanolone, or the endogenous reference compounds pregnanediol, 11- ketoetiocholanolone and 11β-hydroxyandrosterone. Expanded measurement uncertainties at the 95% coverage probability ranged from 0.21‰ to 1.4‰, depending on analyte, instrument and reference material. The measurement results of this comparison were used to estimate a measurement uncertainty of δ(13)C for the certification of the urine reference material being performed on a single instrument using a single reference material at NMI.

  10. IRMS detection of testosterone manipulated with {sup 13}C labeled standards in human urine by removing the labeled {sup 13}C

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jingzhu, E-mail: wangjingzhu@chinada.cn [National Anti-Doping Laboratory, China Anti-Doping Agency, Beijing (China); Yang, Rui [Sport Science College, Beijing Sport University Beijing, Beijing (China); Yang, Wenning [School of Pharmacy, Beijing University of Chinese Medicine, Beijing (China); Liu, Xin; Xing, Yanyi; Xu, Youxuan [National Anti-Doping Laboratory, China Anti-Doping Agency, Beijing (China)

    2014-12-10

    Highlights: • {sup 13}C labeled testosterone can be used to adjust the isotope ratio of testosterone. • The novel testosterone cannot be detected by the regular IRMS method in doping test. • A method was explored to remove the labeled {sup 13}C. • The established method can be used to detect the manipulated testosterone. - Abstract: Isotope ratio mass spectrometry (IRMS) is applied to confirm testosterone (T) abuse by determining the carbon isotope ratios (δ{sup 13}C value). However, {sup 13}C labeled standards can be used to control the δ{sup 13}C value and produce manipulated T which cannot be detected by the current method. A method was explored to remove the {sup 13}C labeled atom at C-3 from the molecule of androsterone (Andro), the metabolite of T in urine, to produce the resultant (A-nor-5α-androstane-2,17-dione, ANAD). The difference in δ{sup 13}C values between Andro and ANAD (Δδ{sup 13}C{sub Andro–ANAD}, ‰) would change significantly in case manipulated T is abused. Twenty-one volunteers administered T manipulated with different {sup 13}C labeled standards. The collected urine samples were analyzed with the established method, and the maximum value of Δδ{sup 13}C{sub Andro–ANAD} post ingestion ranged from 3.0‰ to 8.8‰. Based on the population reference, the cut-off value of Δδ{sup 13}C{sub Andro–ANAD} for positive result was suggested as 1.2‰. The developed method could be used to detect T manipulated with 3-{sup 13}C labeled standards.

  11. Carbon isotope ratio mass spectrometry for detection of endogenous steroid use: a testing strategy.

    Science.gov (United States)

    Ahrens, Brian D; Butch, Anthony W

    2013-07-01

    Isotope ratio mass spectrometry (IRMS) testing is performed to determine if an atypical steroid profile is due to administration of an endogenous steroid. Androsterone (Andro) and etiocholanolone (Etio), and/or the androstanediols (5α- and 5β-androstane-3α,17β-diol) are typically analyzed by IRMS to determine the (13) C/(12) C ratio. The ratios of these target compounds are compared to the (13) C/(12) C ratio of an endogenous reference compound (ERC) such as 5β-pregnane-3α,20α-diol (Pdiol). Concentrations of Andro and Etio are high so (13) C/(12) C ratios can easily be measured in most urine samples. Despite the potentially improved sensitivity of the androstanediols for detecting the use of some testosterone formulations, additional processing steps are often required that increase labour costs and turnaround times. Since this can be problematic when performing large numbers of IRMS measurements, we established thresholds for Andro and Etio that can be used to determine the need for additional androstanediol testing. Using these criteria, 105 out of 2639 urine samples exceeded the Andro and/or Etio thresholds, with 52 of these samples being positive based on Andro and Etio IRMS testing alone. The remaining 53 urine samples had androstanediol IRMS testing performed and 3 samples were positive based on the androstanediol results. A similar strategy was used to establish a threshold for Pdiol to identify athletes with relatively (13) C-depleted values so that an alternative ERC can be used to confirm or establish a true endogenous reference value. Adoption of a similar strategy by other laboratories can significantly reduce IRMS sample processing and analysis times, thereby increasing testing capacity.

  12. Photoaffinity labeling of rat liver microsomal morphine UDP-glucuronosyltransferase by ( sup 3 H)flunitrazepam

    Energy Technology Data Exchange (ETDEWEB)

    Thomassin, J.; Tephly, T.R. (Univ. of Iowa, Iowa City (USA))

    1990-09-01

    Benzodiazepines have been shown to competitively inhibit morphine glucuronidation in rat and human hepatic microsomes. Flunitrazepam exerted a potent competitive inhibition of rat hepatic morphine UDP-glucuronosyltransferase (UDPGT) activity (Ki = 130 microM). It has no effect on the activity of p-nitrophenol, 17 beta-hydroxysteroid, 3 alpha-hydroxysteroid, or 4-hydroxybiphenyl UDPGTs. Because flunitrazepam is an effective photoaffinity label for benzodiazepine receptors, studied were performed in solubilized rat hepatic microsomes and with partially purified preparations of morphine UDPGT to determine the enhancement of flunitrazepam inhibition and binding to morphine UDPGT promoted by exposure to UV light. Under UV light, flunitrazepam inhibition was markedly enhanced. UV light exposure also led to a marked increase in binding of (3H)flunitrazepam to microsomal protein, which was protected substantially by preincubation with morphine. Testosterone, androsterone, and UDP-glucuronic acid did not protect against UV-enhanced flunitrazepam binding, and morphine did not reverse flunitrazepam binding once binding had occurred. As morphine UDPGT was purified, a good correlation was found between the increases in specific activity of morphine UDPGT and flunitrazepam binding to protein. Chromatofocusing chromatography showed that flunitrazepam bound only to fractions containing active morphine UDPGT, and no binding to 4-hydroxybiphenyl UDPGT was observed. Fluorography of a sodium dodecyl sulfate-polyacrylamide electrophoresis gel of solubilized hepatic microsomes that had been treated with (3H) flunitrazepam under UV light revealed a band with a monomeric molecular weight between 54,000 and 58,000. This monomeric molecular weight compares favorably with the reported monomeric molecular weight of homogeneous morphine UDPGT (56,000).

  13. The role of the acquisition methods in the analysis of natural and synthetic steroids and cholic acids by gas chromatography-mass spectrometry.

    Science.gov (United States)

    Andrási, N; Helenkár, A; Vasanits-Zsigrai, A; Záray, Gy; Molnár-Perl, I

    2011-11-11

    An exhaustive GC-MS acquisition study was performed, for the simultaneous analysis of natural and synthetic steroids and cholic acids (in order to insert them into the last tierce of our multiresidue analysis system), such as androsterone, β-estradiol, transdehydroandro-sterone, transdehyroandrosterone, mestranol, dihydrotestosterone, ethinylestradiol, testosterone, norethisterone, estriol, 4-androstene-3,17-dione, gestodene, levonorgestrel, etonogestrel, coprostanol, progesterone, cholesterol, medroxyprogesterone-acetate, lithocholic acid, stigmasterol, cholic acid, chenodeoxycholic acid, β-sitosterol, ursodeoxycholic acid, 3-hydroxy-7-ketocholic acid and dehydrocholic acid, in total 26 compounds. As novelties to the field, for the trimethylsilyl (TMS) oxime ether/ester derivatives of steroids and cholic acids, at first, a tandem mass spectrometric (MS/MS), multiple reaction monitoring (MRM) type acquisition method has been developed in a single run; also for the first time, the three acquisition techniques, the full scan (FS), the selective ion monitoring (SIM), in our case the multiple ion monitoring (MIM) and the currently optimized MRM methods, have been compared; all three, in parallel, under strictly the same derivatization/instrumental conditions, both in matrix free solutions and municipal wastewater from two Hungarian wastewater treatment plants (WWTPs). Critical evaluation of the three acquisition protocols was collated on their analytical performances and validated under the same conditions. The data of six point calibration curves for FS, MIM and MRM methods, showed that both R² (0.9995, 0.9858, 0.9975) and RSD (5.3, 5.8, 5.0), for two parallel derivatizations, each injected three times, proved to be independent of the acquisition processes. Whereas, for the method limit of quantification (LOQ) and the instrument limit of quantification (ILQ) values showed considerable differences. LOQ data, were decreasing in the FS, MIM, MRM line (expressed in ng

  14. Excreção urinária de 17-Cetoesteroides neutros no cavalo normal e no cavalo castrado

    Directory of Open Access Journals (Sweden)

    Fernando Ubatuba

    1954-06-01

    Full Text Available Total urinary neutral 17-steroids were determined in normal and in castrated horses. One liter of a 15-26 hours urine collection was hydrolysed by refluxing with 10% HC1 (v/v for ten minutes and extracted with peroxyde-free ethyl ether. The extract was purified by washing with saturated NaHCO³ and KOH solutions. One half of the crude neutral fraction was fractionated with Girard's "T" reagent . The Zimmermann reaction was performed both in the ketonic and in the crude neutral extracts, using alcoholic 2.5N KOH and a 60 minutes period for the colour development in the dark. Optical density measuments were made in a grating Coleman Universal Spectrophotometer at 420 mµ and 520mµ; for the crude neutral fraction a colour correction equation was applied. The aliquot fraction used for colorimety was adjusted for keeping optical density measurements within the range 0.2 to 0.7. Androsterone (mp. 184-184.5°C with an absorption maximum at 290.5 mµ (Beckman Model DU Spectrophotometer was used as a reference standard. Table I, ilustrates the results obtained. At the 0.05 probability level there is a significant difference among castrated and normal group means (Fischer's "t" test. when were used the data obtained from the ketonic fractions; in spite of the use of a colour correction applied for inespecific chromogens, the same results could not be obtained with the crude neutral fractions, Since Girard's reagent fractionation is generaly accepted as the best method for correcting the inespecific chromogen interference in the determination of the 17-ketosteroids by the Zimmermann reaction, we emphasize the value of the results obtained with the ketonic fractions. From these results it appears, as occurs in others mammals, that castrated horses show a lower level of urinary 17-ketosteroids excretion than the normal horses. The significance of the horse testis contribution for the neutral urinary steroid metabolites is discussed. Since horse urine has a

  15. Characterization of 17α-hydroxysteroid dehydrogenase activity (17α-HSD and its involvement in the biosynthesis of epitestosterone

    Directory of Open Access Journals (Sweden)

    Breton Rock

    2005-07-01

    Full Text Available Abstract Background Epi-testosterone (epiT is the 17α-epimer of testosterone. It has been found at similar level as testosterone in human biological fluids. This steroid has thus been used as a natural internal standard for assessing testosterone abuse in sports. EpiT has been also shown to accumulate in mammary cyst fluid and in human prostate. It was found to possess antiandrogenic activity as well as neuroprotective effects. So far, the exact pathway leading to the formation of epiT has not been elucidated. Results In this report, we describe the isolation and characterization of the enzyme 17α-hydroxysteroid dehydrogenase. The name is given according to its most potent activity. Using cells stably expressing the enzyme, we show that 17α-HSD catalyzes efficienty the transformation of 4-androstenedione (4-dione, dehydroepiandrosterone (DHEA, 5α-androstane-3,17-dione (5α-dione and androsterone (ADT into their corresponding 17α-hydroxy-steroids : epiT, 5-androstene-3β,17α-diol (epi5diol, 5α-androstane-17α-ol-3-one (epiDHT and 5α-androstane-3α,17α-diol (epi3α-diol, respectively. Similar to other members of the aldo-keto reductase family that possess the ability to reduce the keto-group into hydroxyl-group at different position on the steroid nucleus, 17α-HSD could also catalyze the transformation of DHT, 5α-dione, and 5α-pregnane-3,20-dione (DHP into 3α-diol, ADT and 5α-pregnane-3α-ol-20-one (allopregnanolone through its less potent 3α-HSD activity. We also have over-expressed the 17α-HSD in Escherichia coli and have purified it by affinity chromatography. The purified enzyme exhibits the same catalytic properties that have been observed with cultured HEK-293 stably transfected cells. Using quantitative Realtime-PCR to study tissue distribution of this enzyme in the mouse, we observed that it is expressed at very high levels in the kidney. Conclusion The present study permits to clarify the biosynthesis pathway of epiT. It

  16. Genetic Variation in the HSD17B1 Gene and Risk of Prostate Cancer

    Science.gov (United States)

    Kraft, Peter; Pharoah, Paul; Chanock, Stephen J; Albanes, Demetrius; Kolonel, Laurence N; Hayes, Richard B; Altshuler, David; Andriole, Gerald; Berg, Christine; Boeing, Heiner; Burtt, Noel P; Bueno-de-Mesquita, Bas; Calle, Eugenia E; Cann, Howard; Canzian, Federico; Chen, Yen-Ching; Crawford, David E; Dunning, Alison M; Feigelson, Heather S; Freedman, Matthew L; Gaziano, John M; Giovannucci, Ed; Gonzalez, Carlos Alberto; Haiman, Christopher A; Hallmans, Goran; Henderson, Brian E; Hirschhorn, Joel N; Hunter, David J; Kaaks, Rudolf; Key, Timothy; Marchand, Loic Le; Ma, Jing; Overvad, Kim; Palli, Domenico; Pike, Malcolm C; Riboli, Elio; Rodriguez, Carmen; Setiawan, Wendy V; Stampfer, Meir J; Stram, Daniel O; Thomas, Gilles; Thun, Michael J; Travis, Ruth; Trichopoulou, Antonia; Virtamo, Jarmo; Wacholder, Sholom

    2005-01-01

    Steroid hormones are believed to play an important role in prostate carcinogenesis, but epidemiological evidence linking prostate cancer and steroid hormone genes has been inconclusive, in part due to small sample sizes or incomplete characterization of genetic variation at the locus of interest. Here we report on the results of a comprehensive study of the association between HSD17B1 and prostate cancer by the Breast and Prostate Cancer Cohort Consortium, a large collaborative study. HSD17B1 encodes 17β-hydroxysteroid dehydrogenase 1, an enzyme that converts dihydroepiandrosterone to the testosterone precursor Δ5-androsterone-3β,17β-diol and converts estrone to estradiol. The Breast and Prostate Cancer Cohort Consortium researchers systematically characterized variation in HSD17B1 by targeted resequencing and dense genotyping; selected haplotype-tagging single nucleotide polymorphisms (htSNPs) that efficiently predict common variants in U.S. and European whites, Latinos, Japanese Americans, and Native Hawaiians; and genotyped these htSNPs in 8,290 prostate cancer cases and 9,367 study-, age-, and ethnicity-matched controls. We found no evidence that HSD17B1 htSNPs (including the nonsynonymous coding SNP S312G) or htSNP haplotypes were associated with risk of prostate cancer or tumor stage in the pooled multiethnic sample or in U.S. and European whites. Analyses stratified by age, body mass index, and family history of disease found no subgroup-specific associations between these HSD17B1 htSNPs and prostate cancer. We found significant evidence of heterogeneity in associations between HSD17B1 haplotypes and prostate cancer across ethnicity: one haplotype had a significant (p < 0.002) inverse association with risk of prostate cancer in Latinos and Japanese Americans but showed no evidence of association in African Americans, Native Hawaiians, or whites. However, the smaller numbers of Latinos and Japanese Americans in this study makes these subgroup analyses

  17. Genetic variation in the HSD17B1 gene and risk of prostate cancer.

    Directory of Open Access Journals (Sweden)

    Peter Kraft

    2005-11-01

    Full Text Available Steroid hormones are believed to play an important role in prostate carcinogenesis, but epidemiological evidence linking prostate cancer and steroid hormone genes has been inconclusive, in part due to small sample sizes or incomplete characterization of genetic variation at the locus of interest. Here we report on the results of a comprehensive study of the association between HSD17B1 and prostate cancer by the Breast and Prostate Cancer Cohort Consortium, a large collaborative study. HSD17B1 encodes 17beta-hydroxysteroid dehydrogenase 1, an enzyme that converts dihydroepiandrosterone to the testosterone precursor Delta5-androsterone-3beta,17beta-diol and converts estrone to estradiol. The Breast and Prostate Cancer Cohort Consortium researchers systematically characterized variation in HSD17B1 by targeted resequencing and dense genotyping; selected haplotype-tagging single nucleotide polymorphisms (htSNPs that efficiently predict common variants in U.S. and European whites, Latinos, Japanese Americans, and Native Hawaiians; and genotyped these htSNPs in 8,290 prostate cancer cases and 9,367 study-, age-, and ethnicity-matched controls. We found no evidence that HSD17B1 htSNPs (including the nonsynonymous coding SNP S312G or htSNP haplotypes were associated with risk of prostate cancer or tumor stage in the pooled multiethnic sample or in U.S. and European whites. Analyses stratified by age, body mass index, and family history of disease found no subgroup-specific associations between these HSD17B1 htSNPs and prostate cancer. We found significant evidence of heterogeneity in associations between HSD17B1 haplotypes and prostate cancer across ethnicity: one haplotype had a significant (p < 0.002 inverse association with risk of prostate cancer in Latinos and Japanese Americans but showed no evidence of association in African Americans, Native Hawaiians, or whites. However, the smaller numbers of Latinos and Japanese Americans in this study makes

  18. The Endogenous Steroid Profile after Oral Administration of Exemestane%口服依西美坦后尿中内源性甾体排放规律

    Institute of Scientific and Technical Information of China (English)

    刘欣; 杨声; 王静竹; 邢延一; 杨志勇; 徐友宣

    2011-01-01

    Exemestane as the aromatase inhibitor is prohibited by WADA. Because exemestane inhibits the transformation of androgens to estrogens, and thus increases the androgens concentrations in human body. A healthy male voluntarily was administrated per os a single dose of exemestane (25 mg) ·Urinary steroids were analyzed by gas chromatography-mass spectrometry (GC/MS) . Results showed that the concentrations of endogenous steroid increased, and their ratios varied insignificantly. The ratio of testosterone to estrone was raised quickly after exemestane administration. The 13C/12C ratios of androsterone and etiocholanolone in urine (determined by GC/C/IRMS) demonstrated that no other exogenous substance was found. It was shown that exemestane can affect the urinary steroid profile.%依西美坦(exemestane)作为芳香酶抑制剂,因其能够抑制人体内的雄激素向雌激素转变,提高雄激素水平,而被世界反兴奋剂机构(WADA)禁用.本研究通过对一名健康男性志愿者口服单次治疗剂量依西美坦1片(25 mg/片)后,留取15天尿样,采用气相色谱/质谱联用技术,分析其中的内源性甾体激素并逐一定量,分析口服依西美坦后尿中内源性甾体激素的排放规律.结果显示,尿中睾酮等内源性雄性甾体激素浓度有一定增加,几种相关内源性雄性甾体激素比值无明显变化,而睾酮与雌酮浓度比值发生明显变化.采用气相色谱/同位素比质谱技术测定尿中雄酮和本胆烷醇酮的13C/12C比值,耒显示外源性来源.结果提示口服单次治疗剂量依西美坦对尿中内源性甾体激素的排放有一定影响.

  19. Regulation of Dehydroepiandrosterone(DHEA) on cAMP/PKA Signalling System and cAMP-response Element Binding Protein (CREB) in Cultured Primary Chicken Hepatocytes%脱氢表雄酮(DHEA)对鸡胚原代肝细胞cAMP/PKA信号通路和cAMP反应元件结合蛋白(CREB)的影响与调节

    Institute of Scientific and Technical Information of China (English)

    唐雪; 马海田; 邹思湘

    2012-01-01

    Considerable research efforts have been expended to study the factors that are associated with fat deposition in poultry production. Dehydroepiandrosterone (DHEA, 3b-hydroxy-5-androsterone-17-one) is a steroidal compound that is secreted by the mammalian adrenal cortex gland. It is known to be a fat-reducing agent by activation of the steroid hormone receptors. In the present study, cultured primary chicken hepatocytes exposed to DHEA (0,0.01,0.1,1.0 10 and 100 μmol/L, respectively) dissolved in medium were left for 20 min for cAMP assay by RlA(radioimmunoassay) kit. We found that the levels of cAMP were significantly higher in 0.1~100 μmol/L DHEA groups(P0.05). As expected, a full stimulation was achieved at 20 μmol/L forskolin (f0.05). The results suggest that DHEA can activate the cAMP/PKA signaling pathway and regulate lipid metabolism by enhancing CREB phosphorylation level, and provide a better understanding for improvements proposed for DHEA in decrease of body fat in broiler chickens.%控制肉鸡脂肪过多沉积是肉鸡生产中亟待解决的问题.脱氢表雄酮(dehydroepiandrosterone,DHEA)是人体分泌最为丰富的肾上腺类固醇激素,可经由类固醇激素受体介导发挥生理功能,降低机体生脂能力.本研究以鸡胚原代肝细胞为研究对象,选用含DHEA终浓度为0(对照)、0.01、0.1、1.0、10和100μmol/L的培养液孵育肝细胞20 min后收集细胞,放射免疫测定法(RIA)检测胞内cAMP水平.结果发现,0.1~100 μmol/L DHEA孵育肝细胞均可显著提高胞内cAMP水平(P<0.05),其中0.1 μmnol/L DHEA效果最为显著(P<0.01).0.1 μmol/L DHEA孵育肝细胞20 min或1h后收集细胞,RIA法分别检测胞内腺苷酸环化酶(adenylate cyclase,AC)和磷酸二酯酶(phosphodiesterase,PDE)活性,(γ-32P)ATP掺入法测定cAMP依赖性蛋白激酶A(protein kinase A,PKA)活性,Western blot法测定cAMP反应元件结合蛋白(cAMP-response element binding protein,CREB)磷酸化水平.结果显示,0

  20. Influence of Single-bout Resistance Training and Carbohydrate-Protein Supplementation on Urine Androgen Metabolism of Male Boxers and Bodybuilders%急性抗阻运动及不同比例糖和蛋白营养干预对男子力量项目运动员尿雄激素代谢的影响

    Institute of Scientific and Technical Information of China (English)

    文安; 王启荣; 方子龙; 邵晶; 陈成亮; 周钰杰

    2012-01-01

    1-RM with 60-second interval. There was 150-second interval after the fourth set. The last two sets were carried out until the subjects were exhausted. Then,4 sets of bench press at 70% of 1-RM were followed with 60-second interval,and 90-second interval after the last set. Again, 4 sets of bench press at 50% of 1 -RM were followed until the actions of the last two sets could not be repeated. Gas chromatography mass spectrometry (GC-MS) was used to observe urine an-drogen before exercise,and immediately and in the next morning after exercise. Results Etiocholanalone and androsterone in each group increased significantly (P < 0.05) immediately after acute resistance exercise, but there was no difference among the 3 groups. 5α-androstanediol and 5β-androstanediol increased significantly (P < 0.05) in groups HP and LP in the next morning after acute resistance exercise, and they were significantly higher in group HP than that in groups LP and C (P < 0.05). Conclusions Carbohydrate-protein supplementation during acute resistance training can accelerate the transformation and metabolism of gonad androgen and adrenal androgen, promote testosterone transforming to di-hydrotestosterone, and thus benefit the recovery process after acute resistance exercise.

  1. The relationship of adrenal androgen level and insulin resistance in polycystic ovary syndrome pa tients%多囊卵巢综合征患者肾上腺雄激素水平与胰岛素抵抗的关系

    Institute of Scientific and Technical Information of China (English)

    谭庆玲; 张惠; 陈碧玲

    2011-01-01

    强,其肾上腺雄激素的水平可能与胰岛素抵抗有关.%Objective To investigate the relationship between adrenal androgen level and insulin resistance in polycystic ovary syndrome(PCOS)patients.Method Twenty-two healthy women and 85 PCOS patients were underwent adrenocorticptropic hormone(ACTH)stimulation test,and 85 PCOS patients were divided into high response-polycystic ovary syndrome(HR-PCOS)group and normal response-polycystic ovary syndrome(NR-PCOS)group.The ratio of serum luteinizing hormonetofolliclestimulating hormone(LH/FSH),estradiol(E2),testosterone(T)and progestin(P)were tested by radioimmunoassay method.17-hydroxy-progesterone(17-OHP),dehydroepiandros-teronesulfate(DHEAS)and androsterone(AD)was tested at 0 and 60 min after an ACTH stimulation test.Body mass index(BMI),waist-to-hip-circumference radio(WHR)and homeostasis modes of assessment for insulin resistence index(HOMA-IR)were also measured.Results There were 20 cases that 17-OHP levels were higher than normal(HR-PCOS),the other 65 cases were NR-PCOSgroup.MBI and WHR(MBI:x2=13.874,14.512,WHR:x2=12.607,15.153,P all<0.05)of HR-PCOS group and NR-PCOS group were significantly higher than control group,but there had no significant difference between the two PCOS groups(x2=4.801,5.326,P all>0.05).HR-PCOS group and NR-PCOS group were significantly higher than the control group for LH/FSH and estradiol(LH/FSH:x2=18.226,16.327,E2:x2=17.334,19.261,P all<0.05),but there had no significant difference between the two PCOS groups.Serum T of HR-PCOS group was significantly higher than control group(x2=12.274,P <0.01),HR-PCOS group and NR-PCOS group were higher than control group(x2=20.314,18.492,P all<0.01).17-OHP and DHEAS of HR-PCOS group were significantly higher than NR-PCOS group and control group before and after ACTH stimulation test(17-OHP:x2=18.063,19.214,DHEAS:x2=17.358,19.355,P all<0.01).But there had no differences between NR-PCOS group and control group(x2=4.109,4.362,P all>0