Sex-specific activity of hesperidin, diosmin and genistein on human umbilical vein

Flavonoids intake may be associated to beneficial effects on the cardiovascular system. Aim of this study was to investigate biological activities and mechanism of action of two Citrus-derived flavonoids, hesperidin and diosmin, and the estrogenic isoflavone genistein on vascular tone of human umbilical vein (HUV). Umbilical cords obtained at delivery from healthy women were divided into two groups according to the sex of the new-born. Experiments with flavonoids were carried out in serotonin (5-HT)-precontracted HUV rings, before and after tissue pre-treatment with L-NAME (NOS inhibitor) or glybenclamide (K ATP channel blocker). Hesperidin and genistein evoked larger NO-dependent vasorelaxation than diosmin. Endothelium-dependent responses to hesperidin and genistein, but not to diosmin, were gender-specific, being larger in female-as compared with male-derived HUV. Pre-exposure of tissues to L-NAME significantly impaired relaxant responses to hesperidin and genistein and completely blocked those to diosmin. Residual vasorelaxations elicited by hesperidin and genistein after L-NAME pretreatment were blocked by incubation with glybenclamide.