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1.
Arch Toxicol ; 93(7): 1807-1816, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31123801

RESUMO

Recent studies suggest that the anabolic effect of ecdysterone, a naturally occurring steroid hormone claimed to enhance physical performance, is mediated by estrogen receptor (ER) binding. In comparison with the prohibited anabolic agents (e.g., metandienone and others), ecdysterone revealed to be even more effective in a recent study performed in rats. However, scientific studies in humans are very rarely accessible. Thus, our project aimed at investigating the effects of ecdysterone-containing products on human sport exercise. A 10-week intervention study of strength training of young men (n = 46) was carried out. Different doses of ecdysterone-containing supplements have been administered during the study to evaluate the performance-enhancing effect. Analysis of blood and urine samples for ecdysterone and potential biomarkers of performance enhancement has been conducted. To ensure the specificity of the effects measured, a comprehensive screening for prohibited performance-enhancing substances was also carried out. Furthermore, the administered supplement has been tested for the absence of anabolic steroid contaminations prior to administration. Significantly higher increases in muscle mass were observed in those participants that were dosed with ecdysterone. The same hypertrophic effects were also detected in vitro in C2C12 myotubes. Even more relevant with respect to sports performance, significantly more pronounced increases in one-repetition bench press performance were observed. No increase in biomarkers for liver or kidney toxicity was noticed. These data underline the effectivity of an ecdysterone supplementation with respect to sports performance. Our results strongly suggest the inclusion of ecdysterone in the list of prohibited substances and methods in sports in class S1.2 "other anabolic agents".


Assuntos
Anabolizantes/farmacologia , Suplementos Nutricionais , Ecdisterona/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Adulto , Anabolizantes/administração & dosagem , Animais , Desempenho Atlético/fisiologia , Biomarcadores/metabolismo , Linhagem Celular , Método Duplo-Cego , Ecdisterona/administração & dosagem , Humanos , Masculino , Camundongos , Mioblastos/efeitos dos fármacos , Substâncias para Melhoria do Desempenho/administração & dosagem , Treinamento Resistido , Adulto Jovem
2.
Drug Test Anal ; 9(4): 545-552, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27346668

RESUMO

Sport supplements containing steroids never approved for therapeutic use have the potential for abuse by athletes. Most are marketed online and may contain undisclosed steroids yet are readily available despite lacking toxicological or pharmacological evaluation. In this study, 18 supplements purchased online underwent organic solvent extraction to isolate any steroids they contained. From the 18 supplements, 19 steroids were identified and for each, its intrinsic androgenic potency was determined by a yeast cell (Saccharomyces cerevisiae) androgen bioassay and its potential androgenic potency was determined by a liver (HuH7) cell androgen bioassay. The yeast bioassay showed that of the 19 steroids tested, 6 demonstrated strong intrinsic bioactivity, with 4 metabolically activated to even stronger androgens. Moreover, 4 steroids with moderate and 1 with intrinsically weak androgenic bioactivity were activated to more potent androgens. Finally, 8 steroids were metabolically inactivated or deactivated into weaker androgens. Our results show that Internet-sourced sport supplements may contain intrinsically strong androgens, or precursors that can be metabolized to them. These potentially potent pharmacologically active steroids are being used without regulatory control or consumer awareness of their potential adverse effects. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Androgênios/análise , Androgênios/farmacologia , Suplementos Nutricionais/análise , Animais , Linhagem Celular , Dopagem Esportivo , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Internet , Fígado/citologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Camundongos , Mioblastos/citologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Esteroides/análise , Esteroides/farmacologia
3.
Drug Test Anal ; 7(4): 331-5, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25355281

RESUMO

Reports of new designer agents banned in sport being detected in supplements widely available for athletes are constantly emerging. The task of anti-doping laboratories is to control athletes for the presence of substances listed by the World Anti-Doping Agency (WADA) and those that are structurally/biologically similar to them. Recently, a new designer stimulant, N,N-dimethyl-2-phenylpropan-1-amine (NN-DMPPA), was detected by the WADA accredited anti-doping laboratory in Warsaw during routine anti-doping control. The urine samples from four athletes were analyzed in the screening method for stimulants and narcotics and the presence of NN-DMPPA was detected. The identity of NN-DMPPA was confirmed by gas chromatography-mass spectrometry using a synthesized reference standard. The measured concentrations of NN-DMPPA were between 0.51 and 6.51 µg/mL. The presence of the NN-DMPPA compound has been detected in the 'nutritional supplement' NOXPUMP that had been purchased in a store in Poland. NN-DMPPA at 121.7 µg/g was indicated in the investigated supplement together with another banned stimulant ß-methylphenethylamine. The presence of this new stimulant was not indicated on the labelling of the supplement, a situation which is not unusual within this market. Thus, it is important to make athletes aware of the risk related to the use of supplements. Moreover, specific legistation dealing with the commercialization of drugs banned for sport should be undertaken.


Assuntos
Atletas , Drogas Desenhadas/química , Suplementos Nutricionais/análise , Dopagem Esportivo , Propilaminas/urina , Detecção do Abuso de Substâncias/métodos , Urina/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Propilaminas/química
4.
J Chromatogr A ; 1218(33): 5675-82, 2011 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-21752385

RESUMO

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, 5ß-androstane-3α,17ß-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.


Assuntos
Anabolizantes/urina , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Calibragem , Isótopos de Carbono/análise , Cromatografia Gasosa-Espectrometria de Massas/normas , Humanos , Masculino , Detecção do Abuso de Substâncias/normas
5.
Anal Bioanal Chem ; 401(2): 483-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21562740

RESUMO

Currently a large range of pure substance reference materials are available for calibration of doping-control methods. These materials enable traceability to the International System of Units (SI) for the results generated by World Anti-Doping Agency (WADA)-accredited laboratories. Only a small number of prohibited substances have threshold limits for which quantification is highly important. For these analytes only the highest quality reference materials that are available should be used. Many prohibited substances have no threshold limits and reference materials provide essential identity confirmation. For these reference materials the correct identity is critical and the methods used to assess identity in these cases should be critically evaluated. There is still a lack of certified matrix reference materials to support many aspects of doping analysis. However, in key areas a range of urine matrix materials have been produced for substances with threshold limits, for example 19-norandrosterone and testosterone/epitestosterone (T/E) ratio. These matrix-certified reference materials (CRMs) are an excellent independent means of checking method recovery and bias and will typically be used in method validation and then regularly as quality-control checks. They can be particularly important in the analysis of samples close to threshold limits, in which measurement accuracy becomes critical. Some reference materials for isotope ratio mass spectrometry (IRMS) analysis are available and a matrix material certified for steroid delta values is currently under production. In other new areas, for example the Athlete Biological Passport, peptide hormone testing, designer steroids, and gene doping, reference material needs still need to be thoroughly assessed and prioritised.


Assuntos
Anabolizantes/urina , Dopagem Esportivo , Substâncias para Melhoria do Desempenho/urina , Detecção do Abuso de Substâncias/métodos , Dopagem Esportivo/prevenção & controle , Humanos , Espectrometria de Massas , Padrões de Referência , Sensibilidade e Especificidade
6.
Anal Chem ; 83(6): 2065-74, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21329390

RESUMO

Androgenic steroids marketed online as nutraceuticals are a growing concern in sport doping. The inability of conventional mass spectrometry (MS)-based techniques to detect structurally novel androgens has led to the development of in vitro androgen bioassays to identify such designer androgens by their bioactivity. The objective of this study was to determine the androgenic bioactivity of novel steroidal compounds isolated from nutraceuticals using both yeast and mammalian cell-based androgen bioassays. We developed two new in vitro androgen bioassays by stably transfecting HEK293 and HuH7 cells with the human androgen receptor (hAR) expression plasmid together with a novel reporter gene vector (enhancer/ARE/SEAP). The yeast ß-galactosidase androgen bioassay was used for comparison. Our new bioassay featuring the enhancer/ARE/SEAP construct (-S) displayed simpler assay format and higher specificity with lower sensitivity compared with the commonly used mouse mammary tumour virus (MMTV)-luciferase. The relative potencies (RP), defined as [EC(50)] of testosterone/[EC(50)] of steroid, of nutraceutical extracts in the yeast, HEK293-S, and HuH7-S, were 34, 333, and 80,000 for Hemapolin; 208, 250, and 80 for Furazadrol; 0.38, 10, and 106 for Oxyguno; 2.7, 0.28, and 15 for Trena; and 4.5, 0.1, and 0.4 for Formadrol, respectively. The wide discrepancies in rank RP of these compounds was reconciled into a consistent potency ranking when the cells were treated with meclofenamic acid, a nonselective inhibitor of steroid metabolizing enzymes. These findings indicate that steroids extracted from nutraceuticals can be converted in vitro into more or less potent androgens in mammalian but not in yeast cells. We conclude that the putative androgenic bioactivity of a new compound may depend on the bioassay cellular format and that mammalian cell bioassays may have an added benefit in screening for proandrogens but sacrifice specificity for sensitivity in quantitation.


Assuntos
Androgênios/química , Androgênios/farmacologia , Bioensaio/métodos , Suplementos Nutricionais , Saccharomyces cerevisiae/citologia , Esteroides/química , Esteroides/farmacologia , Células HEK293 , Humanos , Receptores Androgênicos/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo
7.
Forensic Sci Int ; 208(1-3): 129-38, 2011 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21177052

RESUMO

Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require criteria that allow endogenous steroids to be distinguished from their synthetic analogues in urine. Methodology based on "looking outside the metabolic box" was used in this study to identify diagnostic urinary markers of 4-androstenediol (4-ADIOL) administration. Androst-2,4-diene-17-one and androst-3,5-diene-17-one are proposed to be formed in urine from acid-catalyzed hydrolysis of 4-ADIOL sulfoconjugate, a major phase II metabolic product of 4-ADIOL. The presence of these markers in the routine gas chromatography-mass spectrometry (GC-MS) steroid screen was suitable to identify samples requiring confirmation by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) - to measure the carbon isotope ratio (δ(13)C) of the androstdiene markers and confirm their likely synthetic origin based on depleted (13)C content.


Assuntos
Anabolizantes/administração & dosagem , Androstanos/urina , Androstenodiol/administração & dosagem , Dopagem Esportivo , Detecção do Abuso de Substâncias/métodos , Androstanos/química , Biomarcadores/urina , Isótopos de Carbono/análise , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estrutura Molecular
8.
Drug Test Anal ; 2(11-12): 557-67, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20967879

RESUMO

Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is the preferred method of confirming the administration of exogenous testosterone by athletes. This relies on synthetic testosterone preparations being depleted in (13) C compared to natural testosterone. There is concern, however, about the existence of synthetic testosterone products that are unexpectedly (13) C-enriched and which may allow athletes to circumvent the current GC-C-IRMS test. Further to the reported studies of legitimate pharmaceutical-grade testosterone products, a detailed analysis of seized materials from border-level seizures was required to obtain intelligence concerning trends in 'black market' testosterone manufacture and distribution. The sample set collected for this study between 2006 and 2009 inclusive provided a δ(13) C range (n = 266) of -22.9‰ to -32.6‰ with mean and median values of -28.4‰ and -28.6‰, respectively. Within this distribution there were 24 samples (9%) confirmed to have δ(13) C values in the range reported for endogenous urinary steroid metabolites (≥ -25.8‰). The benefit of δ(13) C profiling for testosterone preparations was demonstrated by the ability to identify specific seized products that can be target tested for future intelligence purposes. In addition, the potential of stable hydrogen isotope ratio ((2) H/(1) H; δ(2) H) discrimination to complement δ(13) C analysis was investigated. Methodologies for the determination of δ(2) H values by gas chromatography-thermal conversion-isotope ratio mass spectrometry (GC-TC-IRMS) were developed to provide a δ(2) H range (n = 173) of -177‰ to -268‰ with mean and median values of -231‰ and -234‰, respectively.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Preparações Farmacêuticas/química , Testosterona/análise , Isótopos de Carbono/análise , Deutério/análise , Desenho de Equipamento , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Drogas Veterinárias/química
10.
Clin Endocrinol (Oxf) ; 71(3): 417-28, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19170708

RESUMO

CONTEXT: The administration of gonadotrophins is prohibited in sport but the effect in men of recently available recombinant hCG and LH on serum and urine concentrations of gonadotrophins and androgens has not been systematically evaluated in the antidoping context. OBJECTIVE: To determine the time-course of recombinant LH (rhLH) and hCG (rhCG) on blood and urine hormone profiles in men to develop effective tests to detect rhLH and rhCG doping. DESIGN: Two randomized controlled studies with a 2 x 2 factorial design. SETTING: Academic research centre. PARTICIPANTS: Healthy male volunteers aged 18-45 years. INTERVENTIONS: In the rhLH study, men were randomized into (i) either of two single doses of rhLH (75 IU or 225 IU), and (ii) suppression of endogenous LH and testosterone by nandrolone or no suppression. In the rhCG study, men were randomized into (i) either of two single doses of rhCG (250 or 750 microg), and (ii) suppression of endogenous LH and testosterone by nandrolone decanoate (ND) or no suppression. ND suppression comprised a single dose of 200 mg ND 3 days prior to, and in the rhCG study an additional dose 1 day after gonadotrophin injection. MAIN OUTCOME MEASURES: Serum and urine hCG, LH, T, T : LH ratio, urine epitestosterone (E) and urine T : E ratio. RESULTS: Neither rhLH dose produced a significant increase in serum or urine LH or T or in the T : E or T : LH ratios regardless of ND-induced suppression of endogenous LH and T. Nor did an even higher dose (750 IU) in three healthy men with unsuppressed gonadal axis. These findings were confirmed with two different commercial LH immunoassays together with adjustment for any influence of urine sediment and dilution. Both rhCG doses produced a steep, dose-proportional increase in serum and urine hCG with increases in serum and urine T and suppression of serum and urine LH, regardless of hCG dose. Serum but not urine T was lowered by ND suppression. The T : LH ratio showed a progressive increase unrelated to rhCG dose or ND suppression, whereas both rhCG and ND suppression minimally increased T : E ratio. CONCLUSIONS: Both rhCG doses produce a striking increase in serum hCG and T with suppression of serum LH but, at single doses up to 750 IU, rhLH has no influence on serum or urine LH or T. Effective rhLH doping, which relies on a sustained increases in endogenous T, would require much higher and more frequent daily rhLH doses. Use of LH immunoassays optimized for serum to detect rhLH doping by urine LH measurement requires more standardization and validation and, at present, is unreliable. The T : LH ratio is, however, a useful screening test for hCG doping although its utility requires further evaluation.


Assuntos
Androgênios/sangue , Gonadotropina Coriônica/administração & dosagem , Hormônio Luteinizante/administração & dosagem , Testosterona/sangue , Adolescente , Adulto , Androgênios/urina , Gonadotropina Coriônica/sangue , Gonadotropina Coriônica/urina , Dopagem Esportivo , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/urina , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/administração & dosagem , Testosterona/urina , Adulto Jovem
11.
Steroids ; 74(3): 379-92, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19056414

RESUMO

The detection of steroids originating from synthetic precursors in relation to their chemically identical natural analogues has proven to be a significant challenge for doping control laboratories accredited by the World Anti-Doping Agency (WADA). Endogenous steroid abuse may be confirmed by utilising the atomic specificity of gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) that enables the precise measurement of differences in stable isotope ratios that arise as a result of fractionation patterns inherent in the source of steroids. A comprehensive carbon isotope ratio (delta(13)C) profiling study (n=1262) of urinary ketosteroids is reported that demonstrates the inter-individual variation that can be expected from factors such as diet, ethnicity, gender and age within and between different populations (13 countries). This delta(13)C distribution is shown by principal component analysis (PCA) to provide a statistical comparison to delta(13)C values observed following administration of testosterone enanthate. A limited collection of steroid diol data (n=100; consisting of three countries) is also presented with comparison to delta(13)C values of excreted testosterone to validate criteria for WADA accredited laboratories to prove doping offences.


Assuntos
Isótopos de Carbono/análise , Dopagem Esportivo , Esteroides/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Detecção do Abuso de Substâncias/métodos
12.
Drug Test Anal ; 1(11-12): 511-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20355166

RESUMO

The primary screening method for the detection of doping by athletes using synthetic versions of endogenous steroids such as testosterone relies on measurement of the ratio of testosterone (T) to epitestosterone (E) in urine. In 2005 the World Anti-Doping Agency (WADA) lowered the T/E value at which samples undergo further investigation from six to four. This has resulted in a large increase in the number of athletes with naturally elevated T/E ratios undergoing investigation without a corresponding increase in the number of proven doping offences involving testosterone.Our objective was to develop a new simple screening protocol that can, with high probability, not only distinguish athletes whose natural T/E values exceed four from those whose T/E values have been elevated by testosterone doping but also detect those athletes with naturally low T/E values that do not exceed four despite being administered testosterone.Testosterone (250 mg Sustanon) was administered weekly to a group of 47 young adult males for five weeks in a double-blind placebo controlled study and urine samples collected. The samples were analysed for steroid concentrations using GC/MS and for luteinizing hormone (LH) by immunoassay.The elevation of T/E that occurred in all subjects was accompanied by a significant reduction in urinary LH concentrations to levels that are rare in normal subjects.The appropriate measurement of urinary LH, with the measurement of T/E values, can markedly improve the efficiency of detection of doping with testosterone by male athletes, particularly those who have low natural T/E ratios.


Assuntos
Dopagem Esportivo , Hormônio Luteinizante/urina , Detecção do Abuso de Substâncias/métodos , Testosterona/urina , Adulto , Atletas , Método Duplo-Cego , Epitestosterona/urina , Hormônio do Crescimento/administração & dosagem , Humanos , Injeções Intramusculares , Injeções Subcutâneas , Masculino , Placebos , Testosterona/administração & dosagem
13.
Drug Test Anal ; 1(11-12): 587-95, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20355175

RESUMO

Adrenosterone (androst-4-ene-3,11,17-trione, 11-oxoandrostenedione) is an endogenous steroid hormone that has been promoted as a dietary supplement capable of reducing body fat and increasing muscle mass. It is proposed that adrenosterone may function as an inhibitor of the 11beta-hydroxysteroid dehydrogenase type 1 enzyme (11beta-HSD1), which is primarily responsible for reactivation of cortisol from cortisone. The urinary metabolism of adrenosterone was investigated, after a single oral administration in two male subjects, by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Substantially increased excretion of 11beta-hydroxyandrosterone, 11beta-hydroxyetiocholanolone, 11-oxoandrosterone and 11-oxoetiocholanolone was observed. Minor metabolites such as 3alpha,17beta-dihydroxy-5beta-androstan-11-one, 3alpha-hydroxyandrost-4-ene-11,17-dione and 3alpha,11beta-dihydroxyandrost-4-en-17-one were also identified. The exogenous origin of the most abundant adrenosterone metabolites was confirmed by GC-C-IRMS according to World Anti-Doping Agency criteria. Through analysis of a reference population data set obtained from urine samples provided by elite athlete volunteers (n = 85), GC-MS doping control screening criteria are proposed: 11beta-hydroxyandrosterone concentration greater than 10 000 ng/mL (specific gravity adjusted to 1.020) or 11beta-hydroxyandrosterone/11beta-hydroxyetiocholanolone ratio greater than 20.Urine samples fulfilling these screening criteria may be subjected to GC-C-IRMS analysis for confirmation of adrenosterone administration.


Assuntos
Androstenos/normas , Androstenos/urina , Isótopos de Carbono/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Esteroides/normas , Esteroides/urina , Detecção do Abuso de Substâncias/métodos , Androstenos/farmacocinética , Atletas , Suplementos Nutricionais/análise , Dopagem Esportivo , Humanos , Masculino , Valores de Referência , Esteroides/farmacocinética , Detecção do Abuso de Substâncias/normas
14.
Rapid Commun Mass Spectrom ; 22(24): 4147-57, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19025884

RESUMO

Studies have shown that the administration of androstenedione (ADIONE) significantly increases the urinary ratio of testosterone glucuronide to epitestosterone glucuronide (T/E) - measured by gas chromatography/mass spectrometry (GC/MS) - in subjects with a normal ( approximately 1) or naturally high (>1) initial values. However, the urinary T/E ratio has been shown not to increase in subjects with naturally low (<1) initial values. Such cases then rely on the detection of C(6)-hydroxylated metabolites shown to be indicative of ADIONE administration. While these markers may be measured in the routine GC/MS steroid profile, their relatively low urinary excretion limits the use of gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS) to specifically confirm ADIONE administration based on depleted (13)C content. A mass spectrometry strategy was used in this study to identify metabolites of ADIONE with the potential to provide compound-specific detection. C(4)-hydroxylation was subsequently shown to be a major metabolic pathway following ADIONE administration, thereby resulting in urinary excretion of 4-hydroxyandrostenedione (4OH-ADIONE). Complementary analysis of 4OH-ADIONE by GC/MS and GC/C/IRMS was used to confirm ADIONE administration.


Assuntos
Androstenodiona/análogos & derivados , Androstenodiona/urina , Dopagem Esportivo , Espectrometria de Massas por Ionização por Electrospray/métodos , Detecção do Abuso de Substâncias/métodos , Adulto , Cromatografia Gasosa/métodos , Cromatografia Líquida de Alta Pressão , Humanos , Masculino , Programas de Rastreamento/métodos , Reprodutibilidade dos Testes , Espectrofotometria Infravermelho , Adulto Jovem
15.
J Clin Endocrinol Metab ; 93(6): 2213-22, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18381573

RESUMO

CONTEXT: IGF axis proteins and collagen peptides are promising markers of GH abuse. OBJECTIVE: Our objective was to investigate whether responses of serum IGF axis and collagen markers to GH differ between men and women, and are influenced by testosterone (T). DESIGN: This was a randomized, double-blind, placebo-controlled study of 8-wk treatment followed by 6-wk washout. SETTING: The study was performed at a clinical research facility. PARTICIPANTS: A total of 96 recreationally trained healthy athletes (63 men, 33 women), aged 18-40 yr, were studied. INTERVENTION: All subjects received GH (2 mg/d sc) or placebo for 8 wk; men also received T (250 mg/wk im) or placebo for 5 wk. MAIN OUTCOME MEASURES: Serum IGF axis proteins (IGF-I, IGF binding protein-3, and acid labile subunit) and collagen peptides (N-terminal propeptide of type I procollagen, C-terminal telopeptide of type I collagen, and N-terminal propeptide of type III procollagen) were measured. RESULTS: GH induced significant increases in IGF axis and collagen markers that were greater in men than women (P < 0.001). Of the IGF axis markers, IGF-I showed the greatest increase. The relative incremental responses of the collagen markers in general were greater than the IGF markers, especially for PIIINP. The collagen markers increased and decreased more slowly with most remaining elevated (P < 0.01) after 6 wk, in comparison to IGF markers, which returned to baseline within 1 wk. Addition of T to GH amplified the response of PIIINP by more than 1.5-fold but did not affect any other marker. T alone did not affect IGF axis markers but modestly increased collagen markers. CONCLUSIONS: These markers of GH abuse are less responsive in women. The increases in collagen markers have a different time course to the IGF markers and extend the window of detection in both sexes. The response of PIIINP is increased by coadministration of T.


Assuntos
Biomarcadores Farmacológicos/metabolismo , Hormônio do Crescimento/farmacocinética , Caracteres Sexuais , Esportes , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Testosterona/farmacologia , Adolescente , Adulto , Biomarcadores Farmacológicos/sangue , Proteínas de Transporte/sangue , Proteínas de Transporte/metabolismo , Colágeno/metabolismo , Método Duplo-Cego , Feminino , Glicoproteínas/sangue , Glicoproteínas/metabolismo , Hormônios Esteroides Gonadais/sangue , Hormônio do Crescimento/administração & dosagem , Hormônio do Crescimento/efeitos adversos , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Masculino , Placebos , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Testosterona/administração & dosagem
16.
Rapid Commun Mass Spectrom ; 22(3): 321-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18181236

RESUMO

In recent years products containing 6alpha-methylandrost-4-ene-3,17-dione have appeared on the sport supplement market. Scientific studies have proven aromatase inhibition and anabolic and mild androgenic properties; however, no preparation has been approved for medical use up to now. In sports 6alpha-methylandrost-4-ene-3,17-dione has to be classified as a prohibited substance according to the regulations of the World Anti-Doping Agency (WADA). For the detection of its misuse the metabolism was studied following the administration of two preparations obtained from the Internet (Formadrol and Methyl-1-Pro). Several metabolites as well as the parent compounds were synthesized and the structures of 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one, 6alpha-methylandrost-4-ene-3,17-dione, and 5beta-dihydromedroxyprogesterone were confirmed by nuclear magnetic resonance (NMR) spectroscopy. The main metabolite, 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one, was found to be excreted as glucuronide and was still detectable in microg/mL amounts until urine collection was terminated (after 25 h). Additionally, samples from routine human sports doping control had already tested positive for the presence of metabolites of 6alpha-methylandrost-4-ene-3,17-dione. Screening analysis can be easily performed by the existing screening procedure for anabolic steroids using 3alpha-hydroxy-6alpha-methyl-5beta-androstan-17-one as target substance (limit of detection <10 ng/mL). Its discrimination from the closely eluting drostanolone metabolite, 3alpha-hydroxy-2alpha-methyl-5alpha-androstan-17-one, is possible as the mono-TMS derivative.


Assuntos
Dopagem Esportivo/prevenção & controle , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metiltestosterona/urina , Detecção do Abuso de Substâncias/métodos , Urinálise/métodos , Adulto , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Artigo em Inglês | MEDLINE | ID: mdl-16154518

RESUMO

The need for laboratories accredited by the World Anti-Doping Agency (WADA) to develop methods of analysis for steroids excreted primarily as their sulfate conjugates has faced significant analytical challenges. One of the issues relates to the extraction of these metabolites from urine in a relatively pure state. The use of (-)-N,N-dimethylephedrinium bromide as an ion pairing reagent was optimised to produce a method that is selective for the extraction of steroid sulfates prior to GC-MS or LC-MS analysis, with minimal contributions from the urine matrix. The recovery of androsterone from its sulfate conjugate was determined to be 67% with a relative quantitative uncertainty of +/-14% (k = 2).


Assuntos
Anabolizantes/urina , Detecção do Abuso de Substâncias/métodos , Sulfatos/urina , Cromatografia Líquida , Dopagem Esportivo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
J Clin Endocrinol Metab ; 90(11): 5928-36, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16118337

RESUMO

CONTEXT: Management of male infertility and/or androgen deficiency requires accurate hormonal measurements with valid reference intervals. OBJECTIVE: The objective of this study was to develop a valid reference panel of blood samples from healthy eugonadal young men with verified normal reproductive function and to use this panel to evaluate the performance of seven fully automated, commercial multiplex immunoassay platforms used to measure serum total testosterone (T), LH, and FSH. DESIGN: This was an observational study of consistency among seven different automated immunoassays for each of total T, LH, and FSH. Each method was implemented in two laboratories, with each repeating the analysis of the full reference panel samples twice. Serum T concentrations were also measured by gas chromatography/mass spectrometry (GC/MS), and serum inhibin B levels were determined by an ELISA. SETTING: The study was performed at commercial, high-volume, clinical pathology laboratories. PARTICIPANTS: From 147 men screened, sera from 124 healthy, reproductively normal men (age, 21-35 yr) with normal sperm output were used as a reference panel. All laboratories selected for elite performance in the national immunoassay quality assurance program agreed to participate. MAIN OUTCOME MEASURE(S): For each of the 868 assays, descriptive statistics were calculated in the natural and log-transformed scales and were analyzed by nested, repeated measures ANOVA after log transformation. Reference intervals, defined as 95% confidence limits, were calculated using arithmetic (natural scale), geometric (log scale) and nonparametric methods. RESULTS: Descriptive statistics and reference intervals for serum T, LH, and FSH differed widely and significantly between methods, but variation between laboratories for the same assay was negligible. All T methods showed significant differences in regression slope and intercept in deviance plots as well as in estimated reference ranges compared with the independent GC/MS reference method. Although similar between-method differences existed for gonadotropin assays, the smaller quantitative discrepancies allowed assignment of consensus reference intervals for serum FSH (1.3-8.4 IU/liter) and LH (1.6-8.0 IU/liter), although these differed from manufacturers' currently quoted expected values. CONCLUSIONS: Using a reference panel of sera from healthy eugonadal young men with verified normal reproductive function, major differences exist between commercial T immunoassays as well as divergence from the GC/MS standard. This impairs their clinical diagnostic utility and requires substantial improvements in automated T immunoassay technologies or a switch to GC/MS methods. Gonadotropin assays showed less variability, but current high-throughput immunoassays remain suboptimal to confirm accurate diagnosis of azoospermia or androgen deficiency.


Assuntos
Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Testosterona/sangue , Adulto , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Inibinas/sangue , Masculino , Valores de Referência
19.
J Chromatogr Sci ; 43(1): 32-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15808004

RESUMO

The use of gas chromatography (GC)-combustion (C)-isotope ratio mass spectrometry (IRMS) demonstrates that a single oral administration of dehydroepiandrosterone (DHEA, 100 mg) to a male subject significantly lowers the 13C content of etiocholanolone (Et) and androsterone (A) in the subject's urine. The difference in carbon isotope ratio (d13C per thousand) values between Et and A increases from 1.6 per thousand at the time of administration to 5.1 per thousand at 26 h post-administration, indicating preferential metabolism of administered DHEA to form Et in relation to A. Multiple oral administrations of DHEA to a male subject reveals lower d13C values during the excretion period of Et (-31.7 per thousand to -34.6 per thousand) and A (-31.4 per thousand to -33.0 per thousand) to that of the d13C value of the administered DHEA (-31.3 per thousand). Reference distributions of d13C Et and d13C A constructed from normal athlete populations within Australia and New Zealand show a small natural discrimination against 13C in the formation of Et relative to A (mean=0.3 per thousand, n=167, p=0.007). Amplified differences between d13C Et and d13C A, and in vivo 13C depletion measured by GC-C-IRMS are shown to be potentially useful for doping control.


Assuntos
Anabolizantes/isolamento & purificação , Androgênios/isolamento & purificação , Fracionamento Químico/métodos , Dopagem Esportivo/prevenção & controle , Adulto , Androsterona/urina , Austrália , Isótopos de Carbono/urina , Desidroepiandrosterona/administração & dosagem , Desidroepiandrosterona/farmacocinética , Etiocolanolona/urina , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Nova Zelândia , Esportes
20.
J Chromatogr Sci ; 43(1): 39-46, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15808005

RESUMO

Blood substitutes based on hemoglobin or hemoglobin-based oxygen carriers (HBOCs) are oxygen-carrying therapeutic agents developed for use in operations and emergencies in place of donated blood. Increased oxygen-carrying capacity through the use of blood substitutes could help elite athletes to lengthen endurance capacity and improve their performance. As blood substitutes become more readily available, it is essential that a qualitative detection method for their abuse in sport is available. Ideally, such a method would be simple and inexpensive. This study investigates methods that could be used as screening procedures to easily detect HBOCs in plasma and develops tests that can unequivocally confirm their presence. The investigation into the screening method indicates that the direct visual screening of plasma discoloration is the most appropriate with detection limits of less than 1% HBOC in plasma. Two methods are shown to confirm the presence of exogenous hemoglobin in plasma samples, size-exclusion chromatography with photodiode array detection and high-performance liquid chromatography analysis of enzymatic digests with detection by electrospray mass spectrometry. This work emphasizes the need for cooperation between drug developers and sports testing laboratories to ensure that methods for the detection of putative doping agents are available prior to product release.


Assuntos
Substitutos Sanguíneos/análise , Dopagem Esportivo/prevenção & controle , Sequência de Aminoácidos , Animais , Bovinos , Cromatografia em Gel/métodos , Cromatografia Líquida de Alta Pressão/métodos , Hemoglobinas/análise , Hemoglobinas/química , Humanos , Dados de Sequência Molecular , Espectrometria de Massas por Ionização por Electrospray
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