Citrus flavonoids effects on human umbilical vein

Flavonoids intake is associated to beneficial effects on the cardiovascular system. Aim of this study was to investigate the biological activities of hesperidin and diosmin on the vascular tone of human umbilical vein (HUV). Umbilical cords obtained at delivery from healthy women were set up for recording of isometric tension; vasorelaxing activity of flavonoids was assessed in serotonin-precontracted HUV rings. Hesperidin evoked a more profound vasorelaxation than diosmin, and inhibition of NO-synthase significantly impaired relaxant responses to hesperidin but completely abolished those to diosmin. The residual vasorelaxation to hesperidin was prevented by glybenclamide (a KATP channel blocker). Endothelium-dependent responses to hesperidin were larger in female- when compared to male-derived HUV. beta-estradiol and a direct NO-donor compound caused a marked vasorelaxation irrespective of gender of the HUV. Diosmin and, in particular, hesperidin may exert a beneficial effect on the vascular and endothelial function of HUV, and help preventing fetal vascular complications.