Stereostructure-activity mechanism of cyproconazole by cytochrome P450 in rat liver microsomes : a combined experimental and computational study

He, Zongzhe; Wang, Zhen; Gao, Beibei; Liu, Shiling; Zhao, Xuejun; Shi, Haiyan; Wang, Minghua

doi:10.1016/J.JHAZMAT.2021.125764

Title

Stereostructure-activity mechanism of cyproconazole by cytochrome P450 in rat liver microsomes : a combined experimental and computational study

Author

He, Zongzhe

Wang, Zhen

Gao, Beibei

Liu, Shiling

Zhao, Xuejun

Shi, Haiyan

Wang, Minghua

Abstract

Cyproconazole (CPZ), representing the chiral triazole fungicides, is widely used in the pharmaceutical and agricultural fields. To clarify its potential adverse effects on the generalized CYP-mediated processes within mammalian, a comparative experimental and computational approach was employed to investigate the CYP-mediated metabolism processes of CPZ stereoisomers in rat liver microsomes (RLMs). The depletion rate of CPZ stereoisomers in vitro incubation system with RLMs followed the order RR-> SS-> SR-> RS-CPZ. The results of kinetic assays were in line with the depletion rate results. Further inhibition assay confirmed the stereo selective metabolism of CPZ stereoisomers by different CYP isoforms. Molecular dynamics (MD) simulation revealed the stereoselective metabolism mechanism. Several hydrogen bonds and pi-stacking restrict the position of CPZ isomers in the active cavity of CYPs so that the 4'-nitrogen on the triazole ring can bind closely to the heme of CYP, which results in the metabolism of CPZ isomers. By combining the computational and experimental approaches, the structure-activity relationship of CPZ and CYP was elucidated, and this method can be further applied to predict the degree of uncertainty in the process of xenobiotic biotransformation of triazole fungicides and serve as a basis for risk assessment.

Language

English

Source (journal)

Journal of hazardous materials. - Amsterdam

Publication

Amsterdam : 2021

ISSN

0304-3894

DOI

10.1016/J.JHAZMAT.2021.125764

Volume/pages

416 (2021) , 11 p.