title: Disposition of pharmacologically active dietary isoflavones in biological systems.
abstract: Dietary isoflavones, popularly known as phytoestrogens, represent one of the most biologically active classes of flavonoids. Numerous in vitro and in vivo studies provide convincing evidence regarding their beneficial effects on human health. These isoflavones are increasingly being investigated as potential alternate therapies for a range of hormone-dependent conditions, including cancer, menopausal symptoms, osteoporosis and cardiovascular diseases. However, they exhibit poor oral bioavailability which limits their clinical utility in humans. The reason being, they are substrates of a plethora of enzymes and transporters and undergo extensive conjugative metabolism which facilitates their rapid elimination from biological systems. In addition, a number of experimental studies have also revealed that these isoflavones are potent inhibitors of various cytochrome P450 isoforms and transporters which play an important role in the disposition of many commonly prescribed drugs. Thus, there arise chances of observing clinically relevant herb-drug interactions which could sometimes be life-threatening. This review gives a comprehensive understanding of these dietary phytoestrogens with regard to their absorption, biodistribution and the role of enzyme-transporter interplay affecting their disposition in biological systems. Further, the effects of these phytoestrogens on the activity and kinetics of drug metabolizing enzymes and various clinically relevant influx/efflux transporters and the resulting diet-drug interactions have also been discussed.
authors: Academy of Scientific and Innovative Research, New Delhi, India. wahajuddin@cdri.res.in
authors: Wahajuddin
authors: Isha
authors: I
authors: Taneja
authors: Sumit
authors: S
authors: Arora
authors: Kanumuri Siva Rama
authors: KS
authors: Raju
authors: Nida
authors: N
authors: Siddiqui
mesh_terms: D000818:Animals; D003577:Cytochrome P-450 Enzyme System / Q000096:biosynthesis; D004032:Diet; D004790:Enzyme Induction; D006801:Humans; D007408:Intestinal Absorption; D007529:Isoflavones / Q000494:pharmacology*; D026901:Membrane Transport Proteins / Q000378:metabolism; D048789:Phytoestrogens / Q000494:pharmacology*; D014166:Transferases / Q000096:biosynthesis
chemical_list: D007529:Isoflavones; D026901:Membrane Transport Proteins; D048789:Phytoestrogens; D003577:Cytochrome P-450 Enzyme System; D014166:Transferases