Sensitivity of doping biomarkers after administration of a single dose testosterone gel. Issue 5 (28th December 2017)

• Record Type: Journal Article
• Authors: Mullen, Jenny; Börjesson, Annica; Hopcraft, Oscar; Schulze, Jenny J.; Ericsson, Magnus; Rane, Anders; Lehtihet, Mikael; Ekström, Lena
• Is Part Of: Drug testing and analysis. Volume 10:Issue 5(2018)
• Page Start: 839
• Page End: 848
• Publication Date: 2017-12-28
• Subjects: athlete biological passport -- doping in sports -- IRMS -- steroid profile -- testosterone gel; Drugs -- Analysis -- Periodicals; Drug testing -- Periodicals; Chemistry, Forensic -- Periodicals; 615.1901
• DOI: 10.1002/dta.2341
• Languages: English
• ISSNs: 1942-7603

Abstract

Abstract: Micro‐doping with testosterone (T) is challenging to detect with the current doping tests. Today, the methods available to detect T are longitudinally monitoring of urine biomarkers in the Athlete Biological Passport (ABP) and measuring the isotopic composition of excreted biomarkers to distinguish the origin of the molecule. In this study, we investigated the detectability of a single dose of 100 mg T gel in 8 healthy male subjects. We also studied which biomarkers were most sensitive to T gel administration, including blood biomarkers. The ABP successfully detected T gel administration in all 8 subjects. The most sensitive ratio was 5αAdiol/E, however, all ratios showed atypical findings. Isotope ratio mass spectrometry (IRMS) was performed on 5 subjects and only 2 met all the criteria for a positive test according to the rules set by the World Anti‐Doping Agency (WADA). The other 3 showed inconclusive results. Other markers that were affected by T gel administration, not used for this detection today, were serum dihydrotestosterone (DHT) and T as well as reticulocyte count and percentage in whole blood. miRNA‐122 was not significantly affected by the single T dose. A single dose of 100 mg T gel is possible to detect with today's doping tests. Since a single dose of T gel has an impact on some hematological biomarkers, access to both modules of the ABP when evaluating the athletes' profiles will increase the possibility to detect micro‐doses of T. In addition, serum DHT and T may be a useful addition to the future endocrine module of the ABP. Abstract : ABP could detect a single dose of T gel in all of the subjects when three baseline values were present. On the other hand, IRMS only showed positive in 40% of the samples investigated. In addition, serum hormones, such as DHT, should be further investigated as possible complementary biomarkers in longitudinal testing.