Compound specific detection of endogenous steroid abuse in sport: A metabonomic perspective

Abstract

The complementary application of Gas Chromatography-Mass Spectrometry (GC-MS) and Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry (GC-C-IRMS) were used in this study to provide compound specific detection of endogenous steroid misuse for improved anti-doping analysis. Administrations of synthetically derived dehydroepiandrosterone, androstenedione, 4-androstenediol, 5-androstenediol and testosterone were specifically confirmed on the basis of abnonnal urinary excretions and low C content of their respective diagnostic markers; 3oc,5-cyclo-5a-androstane-6p-ol- 17-one, 40H-androstenedione, androst-2,4-diene-17-one/androst-3,5-diene-17-one, etiocholanolone sulfoconjugate and testosterone. A comprehensive reference interval study established the natural variation, predominantly 1 o from diet, observed for 8 C values in an elite athlete population (n = 1262) representing n 13 countries. The minimum 8 C values recorded for the terminal androgen metabolites; androsterone and etiocholanolone were -25.3%o and -25.8%o, respectively. A maximum of i 3.8%o was observed for the associated A8 C value that incorporated 1 lketoetiocholanolone as the endogenous reference compound. Parametric statistics were applied to these data sets to propose high confidence (mean ± 3 standard deviations) 8 C and A813C limits of -27.0%o and 4.0%o to define endogenous steroid abuse. The use of pregnanediol as the endogenous reference compound provided a lower A8I3C limit of 3.0%o. The combinatorial approach to GC-MS and GC-C-IRMS data analysis was used to investigate the potential for metabonomics - the study of a discrete metabolite set - to improve anti-doping science. This methodology allowed the simple interpretation of all relevant information concerning an individual’s metabolism in order to make an informed decision with respect to a doping violation.