In vitro metabolism of an estrogen‐related receptor γ modulator, GSK5182, by human liver microsomes and recombinant cytochrome P450s

Abstract

GSK5182 (4-[(Z)-1-[4-(2-dimethylaminoethyloxy)phenyl]-hydroxy-2-phenylpent-1-enyl]phenol) is a specific inverse agonist for estrogen-related receptor γ, a member of the orphan nuclear receptor family that has important functions in development and homeostasis. This study was performed to elucidate the metabolites of GSK5182 and to characterize the enzymes involved in its metabolism. Incubation of human liver microsomes with GSK5182 in the presence of NADPH resulted in the formation of three metabolites, M1, M2 and M3. M1 and M3 were identified as N-desmethyl-GSK5182 and GSK5182 N-oxide, respectively, on the basis of liquid chromatography-tandem mass spectrometric (LC-MS/MS) analysis. M2 was suggested to be hydroxy-GSK5182 through interpretation of its MS/MS fragmentation pattern. In addition, the specific cytochrome P450 (P450) and flavin-containing monooxygenase (FMO) isoforms responsible for GSK5182 oxidation to the three metabolites were identified using a combination of correlation analysis, chemical inhibition in human liver microsomes and metabolism by expressed recombinant P450 and FMO isoforms. GSK5182 N-demethylation and hydroxylation is mainly mediated by CYP3A4, whereas FMO1 and FMO3 contribute to the formation of GSK5182 N-oxide from GSK5182. The present data will be useful for understanding the pharmacokinetics and drug interactions of GSK5182 in vivo.

Comparative metabolism of four limonoids in human liver microsomes using ultra‐high‐performance liquid chromatography coupled with high‐resolution LTQ‐Orbitrap mass spectrometry

“…Nowadays, human liver microsomes (HLMs) are commonly used in in vitro drug metabolic studies with advantages of high probability of clinical success, easy performance and good repeatability . Previous studies have shown that CYPs exhibited essential functions in the metabolism of the majority of drugs .…”

“…Nowadays, human liver microsomes (HLMs) are commonly used in in vitro drug metabolic studies with advantages of high probability of clinical success, easy performance and good repeatability. [39][40][41][42] Previous studies have shown that CYPs exhibited essential functions in the metabolism of the majority of drugs. [43][44][45][46][47] Meanwhile, high-resolution mass spectrometry (HRMS) is being used extensively in metabolic analyses owing to its accurate MS data and reliable metabolite identification when attempting to discriminate metabolites with different MS/MS fragments.…”

Metabolite identification of bentysrepinine (Y101), a novel anti-HBV agent in rats using a five-step strategy based on a combined workflow with two different platforms of liquid chromatography–tandem mass spectrometry

“…It has been reported previously that N-oxidation is mainly mediated by FMO1/3 or P450s [20][21][22]. Greater insight into the enzymes involved in the formation and elimination of N-oxide metabolite might explain the contribution of FMO or P450s to metabolic eliminations of Y101 and the wide variability of Y101 pharmacokinetics in rats.…”

“…administration to rats using the above five-step strategy in this study. As a consequence, a total of 30 metabolites were observed and Y101 was found to undergo amide hydrolysis, hydroxylation, mono-oxidation, di-oxidation, N-oxidation, methylation, demethylation, hydrogenation and glucuronidation in 21 rats. Proposed structures of all the detective metabolites and metabolic pathways in rats were shown in Fig.…”

Comparative metabolism of tussilagone in rat and human liver microsomes using ultra‐high‐performance liquid chromatography coupled with high‐resolution LTQ‐Orbitrap mass spectrometry

“…In terms of in vitro metabolic analysis of drugs, liver microsome was commonly used as an important alternative means to understand the drug metabolism with advantages of high probability of clinical success, easy performance and good repeatability . The human cytochrome P450s, which are rich in the liver, were believed to include a myriad of enzymatic reactions implicated in important life processes .…”