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1.
Rapid Commun Mass Spectrom ; 34(12): e8776, 2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32143236

RESUMEN

RATIONALE: The misuse of 7-oxo-DHEA (3ß-hydroxyandrost-5-ene-7,17-dione) is prohibited according to the World Anti-Doping Agency (WADA) code. Nevertheless, it is easily available as a dietary supplement and from black market sources. In two recent doping control samples, significant amounts of its main metabolite 7ß-OH-DHEA were identified, necessitating further investigations. METHODS: As both 7-oxo-DHEA and 7ß-OH-DHEA are endogenously produced steroids and no concentration thresholds applicable to routine doping controls exist, the development and validation of a carbon isotope ratio (CIR) mass spectrometry method ha been desirable. Excretion studies encompassing 7-oxo-DHEA, 7-oxo-DHEA-acetate, and in-house deuterated 7-oxo-DHEA were conducted and evaluated with regard to urinary CIR and potential new metabolites of 7-oxo-DHEA. RESULTS: Numerous urinary metabolites were identified, some of which have not been reported before, while others corroborate earlier findings on the metabolism of 7-oxo-DHEA. The CIRs of both 7-oxo-DHEA and 7ß-OH-DHEA were significantly influenced for more than 50 h after a single oral dose of 100 mg, and a novel metabolite (5α-androstane-3ß,7ß-diol-17-one) was found to prolong this detection time window by approximately 25 h. Applying the validated method to routine doping control specimens presenting atypically high urinary 7ß-OH-DHEA levels clearly demonstrated the exogenous origin of 7-oxo-DHEA and 7ß-OH-DHEA. CONCLUSIONS: As established for other endogenously produced steroids such as testosterone, the CIR allows for a clear differentiation between endo- and exogenous sources of 7-oxo-DHEA and 7ß-OH-DHEA. The novel metabolites detected after administration may help to improve the detection of 7-oxo-DHEA misuse and simplify its detection in doping control specimens.

2.
Endocrinology ; 152(12): 4718-28, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21990312

RESUMEN

Various products containing rarely characterized anabolic steroids are nowadays marketed as dietary supplements. Herein, the designer steroid methyl-1-testosterone (M1T) (17ß-hydroxy-17α-methyl-5α-androst-1-en-3-one) was identified, and its biological activity, potential adverse effects, and metabolism were investigated. The affinity of M1T toward the androgen receptor (AR) was tested in vitro using a yeast AR transactivation assay. Its tissue-specific androgenic and anabolic potency and potential adverse effects were studied in a Hershberger assay (sc or oral), and tissue weights and selected molecular markers were investigated. Determination of M1T and its metabolites was performed by gas chromatography mass spectrometry. In the yeast AR transactivation assay, M1T was characterized as potent androgen. In rats, M1T dose-dependently stimulated prostate and levator ani muscle weight after sc administration. Oral administration had no effect but stimulated proliferation in the prostate and modulated IGF-I and AR expression in the gastrocnemius muscle in a dose-dependent manner. Analysis of tyrosine aminotransferase expression provided evidence for a strong activity of M1T in the liver (much higher after oral administration). In rat urine, 17α-methyl-5α-androstane-3α,17ß-diol, M1T, and a hydroxylated metabolite were identified. In humans, M1T was confirmed in urine in addition to its main metabolites 17α-methyl-5α-androst-1-ene-3α,17ß-diol and 17α-methyl-5α-androstane-3α,17ß-diol. Additionally, the corresponding 17-epimers as well as 17ß-hydroxymethyl-17α-methyl-18-nor-5α-androsta-1,13-dien-3-one and its 17-epimer were detected, and their elimination kinetics was monitored. It was demonstrated that M1T is a potent androgenic and anabolic steroid after oral and sc administration. Obviously, this substance shows no selective AR modulator characteristics and might exhibit liver toxicity, especially after oral administration.


Asunto(s)
Sistema Endocrino/efectos de los fármacos , Metiltestosterona/metabolismo , Metiltestosterona/farmacología , Anabolizantes , Andrógenos , Animales , Drogas de Diseño/administración & dosificación , Drogas de Diseño/metabolismo , Drogas de Diseño/farmacología , Suplementos Dietéticos , Humanos , Metiltestosterona/administración & dosificación , Especificidad de Órganos , Ratas , Esteroides/administración & dosificación , Esteroides/metabolismo , Esteroides/farmacología , Testosterona/análogos & derivados
3.
Toxicol Lett ; 201(2): 101-4, 2011 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-21134425

RESUMEN

Since a few years more and more products have appeared on the market for dietary supplements containing steroids that had never been marketed as approved drugs, mostly without proper labeling of the contents. Syntheses and few data on pharmacological effects are available dated back mainly to the 1950s or 1960s. Only little knowledge exists about effects and side effects of these steroids in humans. The present study reports the identification of Δ6-methyltestosterone in a product named "Jungle Warfare", which was obtained from a web-based supplement store. The main urinary metabolites, 17α-hydroxy-17ß-methylandrosta-4,6-dien-3-one (Δ6-epimethyl-testosterone), 17α-methyl-5ß-androstane-3α,17ß-diol (3α,5ß-THMT), and 17ß-methyl-5ß-androstane-3α,17α-diol, as well as the parent compound excreted after a single oral administration were monitored by GC-MS/MS. Δ6-Epimethyltestosterone and 3α,5ß-THMT served for long-term detection (still present in the 181-189 h urine). 17α-Methyltestosterone and its 17-epimer were not detected in the urines (LOD 0.3ng/mL). The highest concentrations were found in the 14-20.5h urine for Δ6-epimethyltestosterone (600 ng/mL), and 3α,5ß-THMT (240 ng/mL) and in the 36-44.5h urine for 17ß-methyl-5ß-androstane-3α,17α-diol (7 ng/mL). For reference methyltestosterone and epimethyltestosterone were dehydrogenated with chloranil. The characterization of the products was performed by GC-MS(/MS) and NMR.


Asunto(s)
Suplementos Dietéticos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Metiltestosterona/análisis , Espectrometría de Masas en Tándem/métodos , Doping en los Deportes , Humanos , Masculino , Metiltestosterona/metabolismo , Persona de Mediana Edad , Estándares de Referencia
4.
Rapid Commun Mass Spectrom ; 23(2): 207-18, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19089863

RESUMEN

The urinary metabolism of the irreversible aromatase inhibitor androsta-1,4,6-triene-3,17-dione was investigated. It is mainly excreted unchanged and as its 17beta-hydroxy analogue. For confirmation, 17beta-hydroxyandrosta-1,4,6-trien-3-one was synthesized and characterized by nuclear magnetic resonance (NMR) in addition to the parent compound. In addition, several reduced metabolites were detected in the post-administration urines, namely 17beta-hydroxyandrosta-1,4-dien-3-one (boldenone), 17beta-hydroxy-5beta-androst-1-en-3-one (boldenone metabolite), 17beta-hydroxyandrosta-4,6-dien-3-one, and androsta-4,6-diene-3,17-dione. The identification was performed by comparison of the metabolites with reference material utilizing gas chromatography/mass spectrometry (GC/MS) of the underivatized compounds and GC/MS and GC/tandem mass spectrometry (MS/MS) of their trimethylsilyl (TMS) derivatives. Alterations in the steroid profile were also observed, most obviously in the androsterone/testosterone ratio. Even if not explicitly listed, androsta-1,4,6-triene-3,17-dione is classified as a prohibited substance in sports by the World Anti-Doping Agency (WADA) due to its aromatase-inhibiting properties. In 2006 three samples from human routine sports doping control tested positive for metabolites of androsta-1,4,6-triene-3,17-dione. The samples were initially found suspicious for the boldenone metabolite 17beta-hydroxy-5beta-androst-1-en-3-one. Since metabolites of androst-4-ene-3,6,17-trione were also present in the urine samples, it is presumed that these findings were due to the administration of a product like 'Novedex Xtreme', which could be easily obtained from the sport supplement market.


Asunto(s)
Androstatrienos/orina , Suplementos Dietéticos/análisis , Doping en los Deportes/prevención & control , Cromatografía de Gases y Espectrometría de Masas/métodos , Drogas Ilícitas/orina , Detección de Abuso de Sustancias/métodos , Urinálisis/métodos , Inhibidores Enzimáticos/análisis , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Analyst ; 131(9): 1021-6, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17047802

RESUMEN

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.


Asunto(s)
Isótopos de Carbono/orina , Doping en los Deportes , Estranos/orina , Detección de Abuso de Sustancias/métodos , Etiocolanolona/orina , Femenino , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Masculino , Nandrolona/orina , Extractos Vegetales
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