Results 241 to 250 of about 75,915 (258)

CYP3A4-based drug–drug interaction: CYP3A4 substrates’ pharmacokinetic properties and ketoconazole dose regimen effect

European Journal of Drug Metabolism and Pharmacokinetics, 2014
The aim of the study was to assess the magnitude of the CYP3A4 inhibitory effect of 2 dosing regimens of ketoconazole and the influence of the pharmacokinetic properties of the CYP3A4 substrate on the extent of the substrate exposure increase. For this purpose, a clinical study was conducted and PBPK modeling simulations were performed.
Xavier, Boulenc, Olivier, Nicolas, Stéphanie, Hermabessière, Isabelle, Zobouyan, Valérie, Martin, Yves, Donazzolo, Céline, Ollier   +6 more
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Metabolic Activation of Benzodiazepines by CYP3A4

Drug Metabolism and Disposition, 2009
Cytochrome P450 3A4 is the predominant isoform in liver, and it metabolizes more than 50% of the clinical drugs commonly used. However, CYP3A4 is also responsible for metabolic activation of drugs, leading to liver injury. Benzodiazepines are widely used as hypnotics and sedatives for anxiety, but some of them induce liver injury in humans.
Katsuhiko, Mizuno, Miki, Katoh, Hirotoshi, Okumura, Nao, Nakagawa, Toru, Negishi, Takanori, Hashizume, Miki, Nakajima, Tsuyoshi, Yokoi   +7 more
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Lessons from the CYP3A4 Promoter

Molecular Pharmacology, 2004
There is considerable interest in determining the molecular basis for human variation in drug response. Investigations over the past 20 years have largely focused on identifying polymorphisms in genes that encode drug metabolism enzymes.
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Transport and Metabolic Characterization of Caco-2 Cells Expressing CYP3A4 and CYP3A4 Plus Oxidoreductase

Pharmaceutical Research, 1999
To further characterize CYP3A4-transfected Caco-2 cells with regard to morphological, transport, and metabolic properties, and to evaluate a different Caco-2 cell strain transfected with both CYP3A4 and oxidoreductase (OR).Transfected Caco-2 cells, Caco-2 TC7 cells, and wild-type Caco-2 cells grown onto Millicell were used.
M, Hu, Y, Li, C M, Davitt, S M, Huang, K, Thummel, B W, Penman, C L, Crespi   +6 more
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Genetic epidemiology of induced CYP3A4 activity

Pharmacogenetics and Genomics, 2011
The cytochrome P450 3A4 (CYP3A4) enzyme is implicated in the metabolism of more than 50% of all prescribed medications and its activity - including induced or inhibited activity - is deemed to be a crucial determinant of interindividual variability in drug disposition, poor therapeutic efficacy, and adverse response to medication.We used the classical ...
Rahmioglu, Nilufer, Heaton, James, Clement, Gail, Gill, Raj, Surdulescu, Gabriela, Zlobecka, Karolina, Hodgkiss, Dylan, Ma, Yongmin, Hider, Robert C., Smith, Norman W., Ahmadi, Kourosh R.   +10 more
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Genetic polymorphisms of CYP3A4: CYP3A4⁎18 allele is found in five healthy Malaysian subjects

Clinica Chimica Acta, 2007
Cytochrome P450 3A4 (CYP3A4) is the major cytochrome involved in metabolizing of >60% of all drugs used in humans. A number of allelic variations in CYP3A4 gene are known to affect catalytic activity including CYP3A4*4, CYP3A4*5 and CYP3A4*18. We investigated the frequencies of CYP3A4*4, CYP3A4*5 and CYP3A4*18 alleles in a Malaysian population.
A B, Ruzilawati, A W Mohd, Suhaimi, S H, Gan   +2 more
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Identification and characterization of CYP3A4*20, a novel rare CYP3A4 allele without functional activity

Clinical Pharmacology & Therapeutics, 2006
The major drug-metabolizing enzyme cytochrome P450 (CYP) 3A4 is genetically conserved. One outlier of Brazilian descent was found in a clinical pharmacokinetic trial exhibiting a 6-fold higher exposure than expected to an investigational drug, shown to be a CYP3A4 substrate.
Anna, Westlind-Johnsson, Robert, Hermann, Andreas, Huennemeyer, Bernhard, Hauns, Gezim, Lahu, Nassr, Nassr, Karl, Zech, Magnus, Ingelman-Sundberg, Oliver, von Richter   +8 more
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CYP3A4*1G regulates CYP3A4 intron 10 enhancer and promoter activity in an allelicdependent manner

Int. Journal of Clinical Pharmacology and Therapeutics, 2015
CYP3A4*1G (G > A) in human CYP3A4 intron 10 is associated with therapeutic effects of CYP3A4-metabolized drugs. The aim of this study was to predict its function in the regulation of CYP3A4 expression.Functional analysis of the CYP3A4*1G allele was performed using bioinformatic methods and enhancer or promoter reporter assays in HepG2 cells ...
Weihong, Yang, Dengzhi, Zhao, Shengna, Han, Zengyuan, Tian, Liang, Yan, Guoqiang, Zhao, Quancheng, Kan, Wei, Zhang, Lirong, Zhang   +8 more
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Modelling atypical CYP3A4 kinetics: principles and pragmatism

Archives of Biochemistry and Biophysics, 2005
The Michaelis-Menten model, and the existence of a single active site for the interaction of substrate with drug metabolizing enzyme, adequately describes a substantial number of in vitro metabolite kinetic data sets for both clearance and inhibition determination.
Houston, J. Brian, Galetin, Aleksandra
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Tiamulin inhibits human CYP3A4 activity in an NIH/3T3 cell line stably expressing CYP3A4 cDNA

Biochemical Pharmacology, 1995
Tiamulin is an antibiotic frequently used in veterinary medicine. The drug has been shown to produce clinically important interactions with other compounds that are administered simultaneously. An NIH/3T3 cell line, stably expressing human cytochrome P450 (EC 1.14.14.1) cDNA (CYP3A4), was used to study the effect of tiamulin on CYP3A4 activity.
E M, De Groene, S M, Nijmeijer, G J, Horbach, R F, Witkamp   +3 more
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