Improvement of endothelium-dependent relaxation in aorta of rat models type 1 and 2 diabetes by hespiridin

Vascular disease is the principal cause of morbidity and mortality in patients with diabetes. A considerable body of evidence implicates oxidative stress as an important pathogenic factor of diabetic vasculopathies. In the present study, the effect of hesperidin, a flavanone glycoside with antioxidant activity, is studied in endothelium-dependent relaxation of the rat aorta in experimental diabetes mellitus type 1 [DM1] and type 2 [DM2]. Single dose intraperitoneal injection of streptozocin [60mg/kg] and subcutaneous daily injection of dexamethasone [10mg/kg for one month] were used to induce DM1 and DM2, respectively. Hesperidin [500mg/kg] was administered orally for two months in DM1 and one month in DM2. The effect of acetylcholine [Ach] on phenyl ephrine [PE] induced. PE contracted aorta was then studied and the EC50 and maximal relaxant effect of Ach were calculated and compared in the two groups. In the experimental DM1, hesperidin restored endothelium-dependent relaxation near to those of normal animals. Its effect on experimental DM2 consisted of a significant reduction of EC50 value of Ach compared to those of diabetic animals. It also showed a great but non-significant effect [P = 0.07] on Ach-induced maximum relaxation compared to DM2 untreated animals. These results show that hesperidin can improve vascular endothelial dysfunction in experimental diabetes mellitus