BIOACTIVITIES OF PLANT FLAVONOIDS AND THE POSSIBLE ACTION MECHANISMS

Flavonoids are isolated from plant extracts and present in diet of humans. They are a subgroup of the more extended family of polyphenols. Epidemiological studies have suggested that flavonoids decrease death from coronary heart disease and stroke incidence. Flavonoids are potent scavengers of reactive species (superoxide, peroxyl radical and peroxynitrite). Some of the activities attributed to flavonoids include antioxidant, antitrombotic, antihypertensive, antiallergic, antiinflammatory, antiapoptotic and anticancerogen. Flavonoids are vasodilatory through a variety of mechanisms and may exert it in endothelium-dependent or independent manners. There is evidence that administration of flavonoids may provide protection against myocardial ischemia-reperfusion. This review presents the possible mechanisms of cardioprotective effects of flavonoids.