Mechanism-based inhibition of human liver microsomal cytochrome P450 1A2 by zileuton, a 5-lipoxygenase inhibitor.

@article{Lu2003MechanismbasedIO,
  title={Mechanism-based inhibition of human liver microsomal cytochrome P450 1A2 by zileuton, a 5-lipoxygenase inhibitor.},
  author={Ping Lu and Michael L. Schrag and Donald E. Slaughter and Conrad E. Raab and Magang Shou and A. David Rodrigues},
  journal={Drug metabolism and disposition: the biological fate of chemicals},
  year={2003},
  volume={31 11},
  pages={
          1352-60
        }
}
  • P. Lu, M. Schrag, +3 authors A. D. Rodrigues
  • Published 1 November 2003
  • Chemistry, Medicine
  • Drug metabolism and disposition: the biological fate of chemicals
Zileuton, a 5-lipoxygenase inhibitor, was evaluated as an inhibitor of cytochrome P450 activity in human liver microsomes. In the absence of preincubation, the racemate was found to be a weak inhibitor (IC50 > 100 microM) of phenacetin O-deethylation (POD) (CYP1A2), paclitaxel 6alpha-hydroxylation (CYP2C8), diclofenac 4'-hydroxylation (CYP2C9), (S)-mephenytoin 4'-hydroxylation (CYP2C19), bufuralol 1'-hydroxylation (CYP2D6), testosterone 6beta-hydroxylation (CYP3A4), chlorzoxazone 6… 
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Inhibitory effects of sanguinarine on human liver cytochrome P450 enzymes.
  • Xiao-yi Qi, S. Liang, +8 authors C. Tu
  • Biology, Medicine
    Food and chemical toxicology : an international journal published for the British Industrial Biological Research Association
  • 2013
TLDR
In vitro-in vivo extrapolation from HLM data showed that more than 35.9% of CYP1A2, CYP2C9, CYp2C8 and CYP3A4 activities in vivo could be inhibited by SAG, suggesting that harmful DDIs could occur when SAG or its medical preparations are co-administered with drugs primarily cleared by these CYP isoforms.
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