Individual susceptibility to environmental, chemical, and drug toxicity is to some extent determined by polymorphism in drug-metabolizing enzymes, in particular the cytochromes P450 (CYPs). This polymorphism is in particular translated into risk differences concerning drugs metabolized by the highly polymorphic enzymes CYP2C9, CYP2C19, and CYP2D6, whereas CYP enzymes active in procarcinogen act...

CYP2C19 is an important human drug-metabolizing enzyme that metabolizes a number of clinically used drugs including the antiulcer drug omeprazole, the anxiolytic drug diazepam, the beta-blocker propranolol, the antimalarial drug proguanil, certain antidepressants and barbiturates, and the prototype substrate S-mephenytoin. Previous studies show that compounds such as rifampicin and dexamethason...

Clopidogrel nonresponsiveness increases the recurrence of cardiovascular events in patients undergoing percutaneous coronary intervention (PCI). Previous studies found that genetic variants such as single nucleotide polymorphisms (SNPs) of CYP2C19 and PON1 may influence clopidogrel response, cause high platelet reactivity (HPR) and increase cardiovascular events. However, these studies were inc...

The impact of pharmacogenetic variants of cytochrome P450 2C19 (CYP2C19) on clopidogrel-mediated effects on platelet inhibition, inflammatory response and endothelial function, as well as risk of major adverse cardiovascular events (MACE), in coronary heart patients undergoing percutaneous coronary intervention (PCI) was investigated. To this end, we assessed the residual platelet aggregation r...

Background: Despite advanced in interventional and medical treatment, mortality after myocardial infarction (MI) remains high, which necessitates the search for predictors of poor outcome. An association between gene CYP2C19 alleles with lower functional activity rates cardiovascular events has been found. In a number studies, negative impact *2 *3 this polymorphic on post-infarction course was...

OBJECTIVE Proton pump inhibitors (PPIs) are frequently coadministered with calcineurin inhibitors (CNIs) such as tacrolimus (TAC) and cyclosporin A (CSA), to treat or prevent upper gastrointestinal complications in Japanese patients with connective tissue diseases (CTDs). The coadministration of PPIs increases the blood concentration of TAC due to drug interaction. We retrospectively investigat...

BACKGROUND Recently published data indicate that the paraoxonase-1 (PON1) Q192R genotype-and not as previously shown activity of cytochrome P450 (CYP) 2C19-is the major determinant of metabolic bioactivation of clopidogrel and thereby variability of antiplatelet effect of clopidogrel. We sought to investigate whether the PON1 Q192R gene polymorphism affects platelet reactivity in patients under...

Upon characterization of baculovirus-expressed cytochrome P-450 (CYP) 2C19, it was observed that this enzyme metabolized (1/2) bufuralol to 1*hydroxybufuralol, a reaction previously understood to be selectively catalyzed by CYP2D6. The apparent Km for this reaction was 36 mM with recombinant CYP2C19, approximately 7-fold higher than for recombinant CYP2D6. The intrinsic clearance for this react...