These guys are ALREADY working to limit the market!!........
;-)
Drug Test Anal. 2018 Sep 25. doi: 10.1002/dta.2512. [Epub ahead of print]
HUMAN IN-VIVO METABOLISM STUDY OF LGD-4033.
Fragkaki AG1, Sakellariou P1,2, Kiousi P1, Kioukia-Fougia N1, Tsivou M1, Petrou M3, Angelis YS1.
Author information
1Doping Control Laboratory of Athens, Olympic Athletic Center of Athens "Spyros Louis", 37 Kifisias Avenue, 15123, Maroussi, Greece.2Faculty of Biology, School of Science, National and Kapodistrian University of Athens, Panepistimioupolis, Zografou, 15771, Athens, Greece.3Cyprus Anti-Doping Authority, Makarion Athletic Centre Avenue, Engomi, Nicosia, CY, 2400, Cyprus.
Abstract
Selective Androgen Receptor Modulators (SARMs) is an emerging class of therapeutics targeted to cachexia, sarcopenia and hypogonadism treatment. LGD-4033 is a SARM which has been included in the Prohibited List annually released by the World Anti-Doping Agency (WADA). The aim of the present work was the investigation of the metabolism of LGD-4033 in a human excretion study after administration of an LGD-4033 supplement, the determination of the metabolites' excretion profiles with special interest in the determination of its long-term metabolites, and the comparison of the excretion time of the phase-I and phase-II metabolites. The results were also compared to those derived from previous LGD-4033 studies concerning both in vitro and in vivo experiments. Supplement containing LGD-4033 was administered to one human male volunteer and urine samples were collected up to almost 21 days. Analysis of the hydrolyzed (with ß-glucuronidase) as well as of the non-hydrolyzed samples was performed using Liquid Chromatography-High Resolution Mass Spectrometry (LC-HRMS) in negative ionization mode and revealed that, in both cases, the two isomers of the dihydroxylated metabolite (M5) are preferred target metabolites. The gluco-conjugated parent LGD-4033 and its gluco-conjugated metabolites M1 and M2 can be also considered as useful target analytes in non-hydrolyzed samples. The study also presents two trihydroxylated metabolites which are identified for the first time in human urine; one of them was recently reported in LGD-4033 metabolism study in horse urine and plasma. |
