Study of the in vitro and in vivo metabolism of a novel synthetic cannabinoid PX-2 in human liver microsomes and zebrafish

Abstract

In vitro and in vivo metabolism of synthetic cannabinoid, N-(1-amino-1-oxo-3-phenylpropan-2-yl)-1-(5-fluropentyl)-1H-indazole-3-carboxamide (PX-2), has been studied based on human liver microsomes and zebrafish using ultra-high-performance liquid chromatography coupled with quadrupole Orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS). The dd-MS2 spectra technique is used to analysis metabolic sites and pathway by accurate mass measurement in the research process. An animal model of zebrafish in vivo metabolism is established to verify the in vitro metabolism pathway of PX-2. The results indicated that 20 kinds of metabolites were generated in the zebrafish animal model and human liver microsome model. Biotransformations mainly occurred at the amino of the compound, and minor reaction occurred at the pentyl chain and benzyl. We recommend M1.1 (PX-2 amide hydrolysis metabolites), and M3.1 (PX-2 oxidative defluorination and hydroxylation) combined M1.4 (PX-2 Phenylalanine loss) to be the potential poisoning markers.