Research Abstract |
Cytochrome P450(CYP)enzymes are home-containing monooxygenases and constitute three families, CYP1, CYP2, and CYP3.These enzymes have been mainly expressed in liver microsomes, and are recognized to be responsible for drug metabolism, carcinogenesis, and degradation of xenobiotics. CYPs are also responsible for the biosynthesis of lipids, steroids, and other secondary metabolites.CYP3A4 is the most abundant enzyme in human liver microsomes ; approximately 30% of the total CYP was suggested to be CYP3A4.Recent investigations have shown that more than 50% of clinically used drugs are oxidized by CYP3A4.It is reported that concomitant oral administration of several foods and herbs affect drug metabolism in humans by inhibiting CYP3A4 activity and that grapefruit juice alters the pharmacokinetics of various drugs, including cyclosporine, midazolam, dihydropyridine-type calcium channel blockers, and triazolam.In the course of our study of.CYP inhibitors, we have reported the isolation and structure elucidation of furanocoumarins, paradisins A, B, and C, from grapefruit juice, bisalkaloids, dipiperamides A-E, from the white pepper Piper nigrum, and three glycosides from the strawberry Fragaria ananassa Duch.cv.Tochiotome.
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