The ability of modafinil to affect human hepatic cytochrome P450 (CYP) activities was examined in vitro. The potential for inhibition of CYP1A2, CYP2A6, CYP2B6, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4/5, and CYP4A9/11 by modafinil (5-250 microM) was evaluated with pooled human liver microsomes. Modafinil exhibited minimal capacity to inhibit any CYP enzyme, except CYP2C19. Modafinil inhibited t...

Cytochrome P450 (P450) fluorometric high-throughput inhibition assays have been widely used for drug-drug interaction screening particularly at the preclinical drug discovery stages. Many fluorometric substrates have been investigated for their selectivity, but most are found to be catalyzed by multiple P450 isozymes, limiting their utility. In this study, 3-O-methylfluorescein (OMF) was examin...

BACKGROUND Clopidogrel requires oxidation dependent on the cytochrome P450 enzyme 2C19 (CYP2C19) to form its active metabolite. The importance of loss-of-function alleles (particularly CYP2C19*2, 681G>A) in poor platelet response to clopidogrel is well recognized. OBJECTIVE To investigate the prevalence and prognostic impact of the CYP2C19*2 allele in a local acute coronary syndrome (ACS) pop...

BACKGROUND Voriconazole is metabolized by cytochrome P450 (CYP) 2C19 and CYP 3A4. Drug-drug interactions and genetic polymorphisms modulate their activities. CASE PRESENTATION A 35-year old African female patient with resistant HIV and a cerebral mass of unknown origin was treated with voriconazole for a suspicion of disseminated Aspergillosis infection. Voriconazole trough concentrations (C0...

Introduction: Since there has been a dearth of research on the assessment of CYP2C19 polymorphism in the east of Iran (Khorasan provinces), this study aimed to detect, CYP2C19*2 and CYP2C19*3 allele frequencies among patients with coronary artery disease. The participants were selected among those referring to Emam Reza Hospital, Mashhad, Iran. Furthermore, the current research was motivated to...

  Background: Cytochrome P450 2C19 (CYP2C19) is important in metabolism of wide range of drugs. CYP2C19*17 is a novel variant allele which increases gene transcription and therefore results in ultra-rapid metabolizer phenotype (URM). Distribution of this variant allele has not been well studied worldwide. The aim of present study was to investigate allele and genotype frequencies of CYP2C19*17 ...

Objective. Potential interactions between herbal extracts and the cytochrome P450 (CYP) system lead to serious adverse events or decreased drug efficacy. Rhus verniciflua stoke (RVS) and its constituents have been reported to have various pharmacological properties. We evaluated the inhibitory potential of RVS and its constituents on the major CYP isoforms. Methods. The effects of allergen remo...

The effects of Buchang Naoxintong Capsules (BNCs) on S-mephenytoin 4'-hydroxylation activities in human liver microsomes in vitro were assessed. Human liver microsome was prepared by different ultracentrifugation. Human liver microsome incubation experiment was carried out to assay BNC on S-mephenytoin 4'-hydroxylation activities. The 4'-hydroxylation of S-mephenytoin, a representative substrat...

CONTEXT The US Food and Drug Administration recently recommended that CYP2C19 genotyping be considered prior to prescribing clopidogrel, but the American Heart Association and American College of Cardiologists have argued evidence is insufficient to support CYP2C19 genotype testing. OBJECTIVE To appraise evidence on the association of CYP2C19 genotype and clopidogrel response through systemat...

The interindividual variability of Proton Pump Inhibitor (PPI) therapy results from the phenotype associated with cytochrome P450 2C19 (CYP2C19) gene, namely CYP2C19*17 allele. Our aim was to characterize patients’ genetic undergoing PPI therapy. A sample 33 oral mucosa cells Portuguese pharmacy patients collected, followed by genotyping. allelic frequencies CYP2C19*1 (-806C) and (-806T) were 7...