Journal of Analytical & Bioanalytical Techniques
Open Access

Abstract

In vitro CYP inhibitory experiments to identify which CYP isozymes are involved metabolisms of new molecular entities are essential for pharmaceutical companies for evaluating drug-drug interactions. While there are several CYP cocktail inhibition assays published, this method outlines new, robust, and simple method for the simultaneous evaluation of the inhibitory effects of nine CYP isozymes. We present the efficient method of cocktail inhibition study toward nine CYP isoforms (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, and CYP3A4/5) in human liver microsomes especially using rosiglitazone for CYP2C8 probe substrates. First of all, to check out the selectivity of rosiglitazone p-hydroxylation and metabolic portion of CYP2C8, 11 recombinant CYPs (CYP1A2, CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP2J2, CYP3A4, and CYP3A5) and anti-body of CYP2C8 were used. These samples were analyzed using API5500 Qtrap equipped with an electrospray ionization (ESI) interface used to generate positive [M+H] + and negative ions [M-H] - . CYP2C8 is selective for the formation of rosiglitazone p-hydroxylation. Moreover, rosiglitazone p-hydroxylation decreased 77.7% in the presence of 20% CYP2C8 antibody and diminished 85.7% in the presence of 100% CYP2C8-antibody compared to the control group. Drug-drug interactions between rosiglitazone and each cocktail substrate in the cocktail set were evaluated. Formation of p-hydroxyrosiglitazone is scarcely unchanged with the individual incubation or with cocktail incubation and formation of metabolites of other substrates also unchanged absence of presence of rosiglitazone. This inhibition screening method is successfully applied to Agilent 6460QQQ.

Biography

Jeong Kee Lee has completed his BS from the Catholic University of Korea, majored in life science. Now, he is in course of M.S. in the Catholic University of Korea and his interest is development of LC-MS/MS assay of drugs and their metabolites in biological samples and metabolite identification and in vitro metabolism in human liver microsomes