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Esquivel A.,University Pompeu Fabra | Pozo O.J.,Bioanalysis Research Group | Garrostas L.,Bioanalysis Research Group | Balcells G.,University Pompeu Fabra | And 3 more authors.
Drug Testing and Analysis | Year: 2016

The aim of this study was to evaluate the direct detection of glucuronoconjugated metabolites of metandienone (MTD) and their detection times. Metabolites resistant to enzymatic hydrolysis were also evaluated. Based on the common mass spectrometric behaviour of steroid glucuronides, three liquid chromatography-tandem mass spectrometry (LC-MS/MS) strategies were applied for the detection of unpredicted and predicted metabolites: precursor ion scan (PI), neutral loss scan (NL), and theoretical selected reaction monitoring (SRM) methods. Samples from four excretion studies of MTD were analyzed for both the detection of metabolites and the establishment of their detection times. Using PI and NL methods, seven metabolites were observed in post-administration samples. SRM methods allowed for the detection of 13 glucuronide metabolites. The detection times, measured by analysis with an SRM method, were between 1 and 22days. The metabolite detected for the longest time was 18-nor-17β-hydroxymethyl-17α-methyl-5β-androsta-1,4,13-triene-3-one-17-glucuronide. One metabolite was resistant to hydrolysis with β-glucuronidase; however it was only detected in urine up to four days after administration. The three glucuronide metabolites with the highest retrospectivity were identified by chemical synthesis or mass spectrometric data, and although they were previously reported, this is the first time that analytical data of the intact phase II metabolites are presented for some of them. The LC-MS/MS strategies applied have demonstrated to be useful for detecting glucuronoconjugated metabolites of MTD, including glucuronides resistant to enzymatic hydrolysis which cannot be detected by conventional approaches. © 2016 John Wiley & Sons, Ltd.

Dvorak J.,FIFA F MARC FIFA Strasse | Baume N.,Lausanne Anti Doping Laboratory | Botre F.,University of Rome La Sapienza | Broseus J.,University of Lausanne | And 23 more authors.
British Journal of Sports Medicine | Year: 2014

A medical and scientific multidisciplinary consensus meeting was held from 29 to 30 November 2013 on Anti-Doping in Sport at the Home of FIFA in Zurich, Switzerland, to create a roadmap for the implementation of the 2015 World Anti-Doping Code. The consensus statement and accompanying papers set out the priorities for the antidoping community in research, science and medicine. The participants achieved consensus on a strategy for the implementation of the 2015 World Anti-Doping Code. Key components of this strategy include: (1) sport-specific risk assessment, (2) prevalence measurement, (3) sport-specific test distribution plans, (4) storage and reanalysis, (5) analytical challenges, (6) forensic intelligence, (7) psychological approach to optimise the most deterrent effect, (8) the Athlete Biological Passport (ABP) and confounding factors, (9) data management system (Anti-Doping Administration & Management System (ADAMS), (10) education, (11) research needs and necessary advances, (12) inadvertent doping and (13) management and ethics: biological data. True implementation of the 2015 World Anti-Doping Code will depend largely on the ability to align thinking around these core concepts and strategies. FIFA, jointly with all other engaged International Federations of sports (Ifs), the International Olympic Committee (IOC) and World Anti-Doping Agency (WADA), are ideally placed to lead transformational change with the unwavering support of the wider antidoping community. The outcome of the consensus meeting was the creation of the ad hoc Working Group charged with the responsibility of moving this agenda forward.

Fabregat A.,Bioanalysis Research Group | Marcos J.,University Pompeu Fabra | Segura J.,University Pompeu Fabra | Ventura R.,University Pompeu Fabra | Pozo O.J.,Bioanalysis Research Group
Drug Testing and Analysis | Year: 2015

The implementation of the athlete steroidal passport in doping control analysis aims to detect intra-individual changes in the steroid profile related to the abuse of anabolic steroids. In this context, the study of intrinsic variations associated with each marker is of utmost importance. In the present work, the influence of several factors in the excretion of the recently reported testosterone metabolites conjugated with cysteine (Δ1-AED; 1,4-androstadien-3,17-dione, Δ6-AED; 4,6-androstadien-3,17-dione, Δ6-T; 4,6-androstadien-17β-ol-3-one, and Δ15-AD; 15-androsten-3,17-dione) is evaluated for the first time. Degradation experiments at 37°C proved that, although the cysteinyl moiety is released, the variation for urinary Δ1-AED/Δ6-AED, Δ1-AED/Δ6-T ratios is less than 30%. Moreover, freeze/thaw cycle testing resulted in RSDs values below 15% for all the analytes. Regarding infradian variability, moderate variations (below 40%) were observed. Additionally, notable alterations in the excretion of these compounds have been observed in the earliest stages of pregnancy. UGT2B17 polymorphism, responsible for the low T/E ratio found in some population, does not influence the excretion of cysteinyl compounds whereas the intake of exogenous substances (alcohol or 5α-reductase inhibitors) dramatically affects their excretion. The urinary concentrations of Δ1-AED, Δ6-AED, and Δ15-AD decreased (<50 %) after the ethanol intake, whereas after the administration of dutasteride, an important increase was observed for the concentrations of Δ6-AED, Δ6-T and Δ15-AD. Overall, the presented data describes the stability of the urinary cysteinyl steroids under the influence of many factors, proving their potential as suitable parameters to be included in the steroidal module of the athlete's biological passport. © 2015 John Wiley & Sons, Ltd.

Ferro P.,Bioanalysis Research Group | Krotov G.,Antidoping Center Moscow Russia | Zvereva I.,Antidoping Center Moscow Russia | Rodchenkov G.,Antidoping Center Moscow Russia | Segura J.,University Pompeu Fabra
Drug Testing and Analysis | Year: 2016

Growth hormone releasing peptides (GHRPs) could be widely used by cheating athletes because they produce growth hormone (GH) secretion, so may generate an ergogenic effect in the body. Knowledge of the essential amino acids needed in GHRP structure for interaction with the target biological receptor GHSR1a, the absorption through different administration routes, and the maintenance of pharmacological activity of potential biotransformation products may help in the fight against their abuse in sport. Several GHRPs and truncated analogues with the common core Ala-Trp-(D-Phe)-Lys have been studied with a radio-competitive assay for the GHSR1a receptor against the radioactive natural ligand ghrelin. Relevant chemical modifications influencing the activity for positions 1, 2, 3, and 7 based on the structure aa-aa-aa-Ala-Trp-(D-Phe)-Lys have been obtained. To test in vivo the applicability of the activities observed, the receptor assay activity in samples from excretion studies performed after nasal administration of GHRP-1, GHRP-2, GHRP-6, Hexarelin, and Ipamorelin was confirmed. Overall results obtained allow to infer structure-activity information for those GHRPs and to detect GHSR1a binding (intact GHRPs plus active metabolites) in excreted urines. © 2016 John Wiley & Sons, Ltd.

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