Direct and metabolism-dependent cytochrome P450 inhibition assays for evaluating drug-drug interactions

Lee, KS; Kim, SK

HERO ID

2903365

Reference Type

Journal Article

Year

2013

Language

English

PMID

21915887

HERO ID 2903365
In Press No
Year 2013
Title Direct and metabolism-dependent cytochrome P450 inhibition assays for evaluating drug-drug interactions
Authors Lee, KS; Kim, SK
Journal Journal of Applied Toxicology
Volume 33
Issue 2
Page Numbers 100-108
Abstract We developed methods for evaluating the ntial inhibition of human cytochrome P450 (CYP) enzymes, including CYP1A2, CYP2A6, CYP2B6, CYP2 C9, CYP2 C19, CYP2D6, CYP2E1 and CYP3A4, using pooled human liver microsomes (HLMs). The CYP inhibition assay used substrate cocktail sets [set A: phenacetin for CYP1A2, coumarin for CYP2A6, (S)-(+)-mephenytoin for CYP2C19, dextromethorphan for CYP2D6 and midazolam for CYP3A4; set B: bupropion for CYP2B6, tolbutamide for CYP2C9, chlorzoxazone for CYP2E1, and testosterone for CYP3A4] with quantitation by liquid chromatography-tandem mass spectrometry. A direct inhibition assay was performed with the substrate cocktails without β-nicotinamide adenine dinucleotide phosphate (NADPH) pre-incubation, and a metabolism-dependent inhibition (MDI) assay was performed after 30 min of pre-incubation with NADPH in HLMs. MDI was identified based on the half-maximal inhibitory concentration (IC(50)) shifts. The IC(50) values of the direct inhibitors determined using the probe substrate cocktails were in good agreement with previously reported values. Eight metabolism-dependent inhibitors including furafylline, 8-methoxypsoralen, tienilic acid, ticlopidine, fluoxetine, paroxetine, disulfiram and verapamil against CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1 and CYP3A4, respectively, resulted in significant IC(50) shifts (≥2.5-fold) after pre-incubation. Thus, these CYP inhibition assays are considered to be useful tools for evaluating both direct inhibition and MDI at an early stage of the drug discovery and development process.
Doi 10.1002/jat.1720
Pmid 21915887
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English