Abstract

Bioflavonoids have a variety of biological effects in various mammalian cell systems both in vitro and in vivo. There are very few reports on their pharmacokinetics following administration in pure forms. Bioflavonoids have been implicated in quit a few drug interactions. These interactions seem to Involve Cytochrome P450 and/or P-glycoprotein. In this review the available details on pharmacokinetics of various bioflavonoids in animals and human and the influence on Cytochrome P450 and P-glycoprotein have been presented. Further, the pharmacokinetic parameters like Cmax Tmax T1/2 and AUC of bioflavonoids and the effect of dose on these parameters have been discussed. The available information on bioflavonoids biotransformations, such as methylation, sulfo-or glucuro-conjugations by different transferases in liver, has been reported. Different metabolites of quercetin (a widely investigated molecule), their metabolic pathways, clearance and volume of distribution of different bioflavonoids have been cited. Bioflavonoids have been reported to Interact with cytochrome P450 lsozymes particularly with 3A4 series and therefore, may alter the disposition of the concurrently administered drugs. P-glycoprotein, an important membrane protein, is produced as a result of mdr1 gene expression and is responsible for development of cytotoxic drug resistance in cancer. It has been reported that P-glycoprotein activity seems to be modulated by bioflavonoids. The reports on modulation of P-glycoprotein by bioflavonoids using cell line models have been reviewed and presented.