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1.
Drug Test Anal ; 11(8): 1218-1230, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30932347

RESUMO

The introduction of alternative markers to the steroid profile can be an effective approach to improving the screening capabilities for the detection of testosterone (T) misuse. In this work, endogenous steroid sulfates were evaluated as potential markers to detect intramuscular (IM) T administration. Fourteen sulfate metabolites were quantified using mixed-mode solid-phase extraction and analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Urine samples after a single IM injection (100 mg) of T cypionate to six Caucasian and six Asian healthy male volunteers were analyzed. Principal component analysis (PCA) was used to characterize the sample cohort and to obtain the most useful markers for discrimination between pre- and post-administration samples. For Caucasian volunteers, a separation between pre- and post-administration samples was observed in PCA, whereas for Asian volunteers no separation was obtained. Seventeen ratios between sulfate metabolites were selected and further considered. Detection times (DTs) of each marker were evaluated using individual thresholds for each volunteer. The best results were obtained using ratios involving T and epitestosterone (E) sulfates in the denominator. The best marker was the ratio androsterone sulfate/testosterone sulfate (A-S/T-S) which prolonged the DT 1.2-2.1 times in respect to those obtained using T/E ratio in all Caucasian volunteers and 1.3-1.5 times in two Asian volunteers. Other ratios between A-S or etiocholanolone sulfate and E-S, and sulfates of etiocholanolone, dehydroandrosterone or epiandrosterone, and T-S were also found adequate. These ratios improve the DT after IM T administration and their incorporation to complement the current steroid profile is recommended.


Assuntos
Anabolizantes/urina , Androgênios/urina , Epitestosterona/urina , Sulfatos/urina , Testosterona/urina , Anabolizantes/administração & dosagem , Anabolizantes/metabolismo , Androgênios/administração & dosagem , Androgênios/metabolismo , Povo Asiático , Cromatografia Líquida , Doping nos Esportes , Epitestosterona/administração & dosagem , Epitestosterona/metabolismo , Humanos , Injeções Intramusculares , Masculino , Detecção do Abuso de Substâncias , Sulfatos/metabolismo , Espectrometria de Massas em Tandem , Testosterona/administração & dosagem , Testosterona/metabolismo , População Branca
2.
Steroids ; 62(10): 665-73, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9381514

RESUMO

The basis of a potential method for confirming intake of four natural androgens (testosterone, epitestosterone, dihydrotestosterone, and dehydroepiandrosterone is presented. The method relies on isolating from urine a steroid fraction containing androstenediol and androstanediol metabolites of these natural steroids and analyzing their 13C content by gas chromatography, combustion, isotope ratio mass spectrometry. The steroids were recovered from urine by conjugate hydrolysis with a Helix pomatia preparation (sulfatase and beta-glucuronidase), Girard T reagent separation to obtain a nonketonic fraction, and Sephadex LH-20 chromatography for purification. Metabolites appropriate for all of the natural steroids could be separated (as diacetates) by gas chromatography on a DB-17 capillary column viz.: 5 alpha (and beta)-androstane-3 alpha,17 alpha-diol (epitestosterone as precursor); 5 alpha (and beta)-androstane-3 alpha,17 beta-diol (testosterone as precursor); 5-androstene-3 beta,17 beta-diol (dehydroepiandrosterone precursor); and 5 alpha-androstane-3 alpha,17 beta- (and 17 alpha-) diol (dihydrotestosterone precursor). Measurement of the 13C content of the specific analytes after ingestion of the androgen precursors demonstrated a lowering of delta 13C/1000 value compared to normal values. Typically, in the male individual studied, delta 13C/1000 values for all components were -26 to -27 before drug administration and -29 to -30 at 6 h after, the latter values reflecting those obtaining for commercial synthetic steroid compared to in vivo synthesized steroid. While generally the metabolism of the steroids was as expected, this was not the case for 5 alpha-dihydrotestosterone. A major metabolite was 5 alpha-androstane-3 alpha,17 alpha-diol, which had presumably been formed by 17 beta/17 alpha isomerization, a process previously known for unnatural anabolics but not for natural hormones. The isolation, purification, and isotope ratio mass spectrometry techniques described may form the basis of a general method for confirming natural steroid misuse by sports participants.


Assuntos
Androstano-3,17-diol/urina , Androstenodiol/urina , Desidroepiandrosterona/administração & dosagem , Di-Hidrotestosterona/administração & dosagem , Doping nos Esportes , Epitestosterona/administração & dosagem , Feminino , Cromatografia Gasosa-Espectrometria de Massas/métodos , Humanos , Masculino , Detecção do Abuso de Substâncias/métodos
3.
J Endocrinol ; 142(2): 353-60, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7931008

RESUMO

Testosterone administration to male athletes can be safely detected in the vast majority of cases by the urinary excretion ratio of testosterone to epitestosterone glucuronides (TG/EG), which may not exceed 6. Some rare cases of physiologically high TG/EG ratios (between 6 and 12) are encountered; these may be attributed to a dysregulation of the testicular secretions of epitestosterone which is decreased, and of epitestosterone sulphate (ES) which is normal or increased. Impaired hydrolysis of circulating epitestosterone sulphate by deficiency of a specific sulphatase acting on 17 alpha-sulphates must also be considered as a possible reason for the decreased availability of epitestosterone for hepatic glucuronidation. Urinary excretions of conjugates and metabolites of testosterone and epitestosterone (expressed in nmol/mmol creatinine) have been determined by gas chromatography-mass spectrometry associated with stable isotope dilution, in a reference population of 90 healthy male subjects and in 12 subjects with chronic TG/EG > 4. Urinary excretion ratios such as TG/(EG+ES), EG/ES and TG/5-androstene-3 beta,17 alpha-diol glucuronide are shown to be efficient criteria which allow discrimination between physiologically high and pharmacologically high TG/EG ratios. A simple oral loading test with deuterium-labelled epitestosterone demonstrates the difference between hepatic and total epitestosterone metabolism clearly, particularly in subjects with physiologically high TG/EG in comparison with subjects with normal TG/EG.


Assuntos
Epitestosterona/urina , Esportes , Detecção do Abuso de Substâncias , Testosterona/urina , Adolescente , Adulto , Deutério , Epitestosterona/administração & dosagem , Epitestosterona/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Técnicas de Diluição do Indicador , Marcação por Isótopo , Fígado/metabolismo , Masculino , Radioimunoensaio , Valores de Referência , Sensibilidade e Especificidade , Testosterona/análogos & derivados
4.
Clin Chem ; 40(1): 106-9, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8287515

RESUMO

Combined self-administration of testosterone (T) and epitestosterone (ET) by athletes counteracts the efficiency of the corresponding urinary glucuronides (G) ratio, (T/ET)G, as an indicator of T abuse. I therefore propose 5-androstene-3 beta, 17 alpha-diol (5A3 beta 17 alpha), the immediate metabolic precursor of ET, as a new reference compound for the expression of relative excretions of T and ET. Thus (T/5A3 beta 17 alpha)G and (ET/5A3 beta 17 alpha)G become potential criteria to indicate joint administration of T and ET, since their respective threshold values (2.5 and 1.5) are exceeded even when (T/ET)G remains below the critical value of 6.


Assuntos
Epitestosterona/urina , Esportes , Detecção do Abuso de Substâncias , Testosterona/urina , Adolescente , Adulto , Epitestosterona/administração & dosagem , Epitestosterona/farmacocinética , Reações Falso-Negativas , Glucuronatos/urina , Humanos , Masculino , Valores de Referência , Automedicação , Testosterona/administração & dosagem , Testosterona/farmacocinética
5.
J Steroid Biochem Mol Biol ; 45(4): 321-4, 1993 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8499340

RESUMO

Immature ovariectomized female rats primed with estradiol or without estrogen priming were treated with epitestosterone i.p. After 7 h blood was collected and LH and FSH levels were determined. The dose-response relationship was a biphasic one. LH and less markedly FSH levels decreased under epitestosterone treatment with doses up to 10 mg, whereas at higher doses an increase of gonadotrophins was observed.


Assuntos
Epitestosterona/farmacologia , Hormônio Foliculoestimulante/sangue , Hormônio Luteinizante/sangue , Animais , Relação Dose-Resposta a Droga , Epitestosterona/administração & dosagem , Estradiol/farmacologia , Feminino , Injeções Intraperitoneais , Ovariectomia , Ratos , Ratos Wistar , Receptores de Estrogênio/efeitos dos fármacos
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