Identification and characterization of GSK-9089 metabolites through high resolution-mass spectrometry based in vitro and in vivo rat biological sample analysis

Estrogen related receptors (ERRs) agonist GSK-9089 (DY-131) reported to pose a potential in increasing exercise endurance. High resolution mass spectrometry (HRMS) based analysis has utmost importance in the detection, identification, or characterization of a molecule including its metabolites in human body. In this study, in vitro metabolism profile of GSK-9089 was investigated after incubation with liver microsomes and S9 fractions. Additionally, in vivo metabolites of the molecule were identified in plasma, urine, and faeces samples of rats. Structures of all the potential metabolites were revealed by employing an in silico tool and HRMS based analysis through data-dependent and data-independent mining strategies. Nine unknown metabolites of GSK-9089 have been identified which were found to be present in a trace amount in in vivo matrices. Most of the in vitro and in vivo phase I metabolites of the molecule were formed after imine bond hydrolysis followed by deamidation, oxidation, and N-oxidation. The molecule underwent phase II metabolism to generate more polar metabolites mainly through glucuronide, sulfate conjugation biotransformation reactions. The in vitro and in vivo metabolites of GSK-9089 could be useful to identify the abuse of this ERRs agonist in the future.