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Characterization and quantitation of a sulfoconjugated metabolite for detection of methyltestosterone misuse and direct identification by LC-MS. | LitMetric

AI Article Synopsis

  • - Methyltestosterone (MT) is a commonly misused anabolic steroid, and its primary sulfate metabolite, S2, has a long detection window but lacked confirmed structural evidence until now.
  • - This study developed a method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to identify S2 without needing complex sample prep, and it included both in vitro and in vivo analyses to solidify findings.
  • - By synthesizing and characterizing a reference standard of S2, the researchers provided definitive identification information, which is expected to improve anti-doping testing and evaluation methods.

Article Abstract

Methyltestosterone (MT) is one of the most frequently misused anabolic androgenic steroids detected in doping control analysis. The metabolism of MT in humans leads to several phase І metabolites and their corresponding phase Ⅱ conjugates. Previous studies have postulated the 3α-sulfoconjugate of 17α-methyl-5β-androstane-3α,17β-diol (S2) as principal sulfate metabolite of MT, with a detection window exceeding 10 days. However, a final direct and unambiguous confirmation of the structure of this metabolite is missing until now. In this study, we established an approach to detect and identify S2, using intact analysis by liquid chromatography hyphenated with tandem mass spectrometry (LC-MS/MS) without complex sample pretreatment. An in vitro study yielded the LC-MS/MS reference retention times of all 3-sulfated 17-methylandrostane-3,17-diol diastereomers, allowing for accurate structure assignment of potentially detected metabolites. In an in vivo excretion study with a single healthy male volunteer, the presence of the metabolite S2 was confirmed after a single oral dose of 10 mg MT. The reference standard was chemically synthesized, characterized by accurate mass mass spectrometry (MS) and nuclear magnetic resonance (NMR), and quantified by quantitative NMR (qNMR). Thus, this study finally provides accurate structure information on the S2 metabolite and a direct analytical method for detection of MT misuse. The availability of the reference material is expected to facilitate further evaluation and subsequent analytical method validation in anti-doping research.

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Source
http://dx.doi.org/10.1016/j.jsbmb.2024.106527DOI Listing

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