Results 261 to 270 of about 56,913 (295)

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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CYP3A4*16 and CYP3A4*18 Alleles Found in East Asians Exhibit Differential Catalytic Activities for Seven CYP3A4 Substrate Drugs

Drug Metabolism and Disposition, 2010
CYP3A4, the major form of cytochrome P450 (P450) expressed in the adult human liver, is involved in the metabolism of approximately 50% of commonly prescribed drugs. Several genetic polymorphisms in CYP3A4 are known to affect its catalytic activity and to contribute in part to interindividual differences in the pharmacokinetics and pharmacodynamics of ...
Keiko, Maekawa, Noriko, Harakawa, Takuya, Yoshimura, Su-Ryang, Kim, Yoshiyuki, Fujimura, Fumika, Aohara, Kimie, Sai, Noriko, Katori, Masahiro, Tohkin, Mikihiko, Naito, Ryuichi, Hasegawa, Haruhiro, Okuda, Jun-ichi, Sawada, Takuro, Niwa, Yoshiro, Saito   +14 more
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Human variability in CYP3A4 metabolism and CYP3A4-related uncertainty factors for risk assessment

Food and Chemical Toxicology, 2003
CYP3A4 constitutes the major liver cytochrome P450 isoenzyme and is responsible for the oxidation of more than 50% of all known drugs. Human variability in kinetics for this pathway has been quantified using a database of 15 compounds metabolised extensively (>60%) by this CYP isoform in order to develop CYP3A4-related uncertainty factors for the risk ...
Dorne, J.L.C.M., Walton, K., Renwick, A.G.   +2 more
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CYP3A4 variant alleles in white individuals with low CYP3A4 enzyme activity

Clinical Pharmacology & Therapeutics, 2002
ObjectiveOur objective was to evaluate the presence of CYP3A4 gene variants in white individualswith low CYP3A4 enzyme activity.MethodsPersons with extremely low enzyme activity, either in vitro or in vivo, were selected in a panel of 97 healthy subjects. Genetic analyses for CYP3A4 variant alleles present in white subjects, including CYP3A4*1B, CYP3A4*
Elena, García-Martín, Carmen, Martínez, Rosa M, Pizarro, Francisco J, García-Gamito, Harriet, Gullsten, Hannu, Raunio, José A G, Agúndez   +6 more
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Utility of CYP3A4 and PXR-CAR-CYP3A4/3A7 Transgenic Mouse Models To Assess the Magnitude of CYP3A4 Mediated Drug–Drug Interactions

Molecular Pharmaceutics, 2017
Species differences in the expression, activity, regulation, and substrate specificity of metabolizing enzymes preclude the use of animal models to predict clinical drug-drug interactions (DDIs). The objective of this work is to determine if the transgenic (Tg) Cyp3a-/-Tg-3A4Hep/Int and Nr1i2/Nr1i3-/--Cyp3a-/-Tg-PXR-CAR-3A4/3A7Hep/Int (PXR-CAR-CYP3A4 ...
Justin Q. Ly, Kirsten Messick, Ann Qin, Ryan H. Takahashi, Edna F. Choo   +4 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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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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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 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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Effects of Metronidazole on Hepatic CYP3A4 Activity

Pharmacotherapy: The Journal of Human Pharmacology and Drug Therapy, 2001
Study Objective. To evaluate the effect of a short course of oral metronidazole, commonly used for bowel‐preparation regimens, on hepatic cytochrome P450 (CYP) 3A4 activity, as measured by the [14C N‐methyl]‐erythromycin breath test (ERMBT) in healthy volunteers.Design. Prospective, nonrandomized, interventional study.Setting.
C E, Haas, D C, Kaufman, R C, DiCenzo
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