Cited by 31Doping in SportsPharmacological Effects and AssaysForensic Toxicology and Drug Analysis

Determination of 13C/12C ratios of urinary epitestosterone and its main metabolites 5α‐ and 5β‐androstane‐3α, 17α‐diol

Piper, Thomas, Riemann, Phillip, Opfermann, Georg, Mareck, Ute, Geyer, Hans, Vajiala, Graziela, Flenker, Ulrich, Schänzer, Wilhelm·2009·Drug Testing and Analysis

Abstract

Epitestosterone (17alpha-hydroxy-androst-4-en-3-one, EpiT) belongs to the list of prohibited substances of the World Anti-Doping Agency (WADA). Although it possesses no anabolic effect, it is presumed to be misused by athletes in order to mask administration of testosterone (T) by lowering the urinary T/EpiT ratio.To improve detection, an excretion study with 40 mg of orally administered EpiT was conducted focusing on the metabolites of EpiT: 5alpha- and 5beta-androstane-3alpha,17 alpha-diol (5aEpiD and 5bEpiD). A reference population of n = 74 volunteers was investigated to elucidate the urinary concentrations of these steroids.In order to prove whether an unusual finding in urinary concentrations or ratios is due to an illicit intake of steroids or due to physiological elevation, determination of carbon isotope ratios is advisable. A method for isotope ratio determination was developed to enable (13)C/(12)C ratios of EpiT, 5bEpiD, 5aEpiD, pregnanediol and androsterone and etiocholanolone to be measured from a single urine specimen. The method's validity was tested by applying linear mixing models and specificity was ensured by means of gas chromatography/mass spectrometry analysis. delta(13)C values at natural levels were determined with a reference population and both Delta values and corresponding reference limits were calculated.Considering the implemented EpiT-metabolites, a more than twofold extension of the detection time of EpiT administration was achieved with both the urinary concentration thresholds and the (13)C/(12)C ratios.

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Crossref · 10.1002/dta.53

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  • Excreted metabolites of EpiT are 5α- and 5β-androstane-3α,17α-diols.

    “Excreted metabolites of EpiT are 5α- and 5β-androstane-3α,17α-diols (Piper et al., 2009, Shackleton et al., 1997b, Wilson and Lipsett, 1966).”

    From Intracrine androgen biosynthesis, metabolism and action revisited (2018) · cites this paper as Piper et al., 2009

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Authors
Piper, T., Riemann, P., Opfermann, G., Mareck, U., Geyer, H., Vajiala, G., Flenker, U., & Schänzer, W.
Affiliations
German Sport University Cologne (DE)
Corresponding author
Piper, Thomas
Venue
Drug Testing and Analysis
Publisher
Wiley
Published
2009-09-22
Volume
1
Issue
11-12
Pages
576-586
ISSN
  • 1942-7603 (ISSN-L)
  • 1942-7611
OpenAlex
W2105853715
Cited by
31
References
35
Citations by year
2024: 1 · 2021: 3 · 2017: 2 · 2016: 1 · 2015: 2 · 2014: 1 · 2013: 1 · 2012: 7
FWCI
21.65
Type
journal article
Language
en
Open access
closed
Locations
  • Drug Testing and Analysis (publishedVersion)
  • PubMed (publishedVersion)
Funders
World Anti-Doping Agency
Topics
  • Social Sciences › Sociology and Political Science › Doping in Sports
  • Life Sciences › Agricultural and Biological Sciences › Animal Science and Zoology › Pharmacological Effects and Assays
  • Life Sciences › Pharmacology, Toxicology and Pharmaceutics › Toxicology › Forensic Toxicology and Drug Analysis
Keywords
epitestosterone, 13C/12C isotope ratio, urinary steroid metabolites, anti-doping, testosterone, detection window, reference population, linear mixing model, pregnanediol, androsterone, etiocholanolone
MeSH terms
Androsterone, Carbon Isotopes, Doping in Sports, Epitestosterone, Etiocholanolone, Humans, Male, Pregnanediol, Reference Values, Reproducibility of Results, Substance Abuse Detection, Linear Models

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