The Sesame Lignan Sesamin Attenuates Vascular Permeability in Rats with Streptozotocin-Induced Diabetes: Involvement of Oxidative Stress

Background: Cardiovascular disorders are a major cause of morbidity and mortality in diabetic patients. Increased vascular permeability is a hallmark of diabetic vasculopathy, and the administration of natural products with antioxidant activity could restore vascular function. Objectives: In this study, the effect of chronic treatment with sesamin on vascular permeability in rats with streptozotocin (STZ)-induced diabetes was investigated. Materials and Methods: Male diabetic rats received sesamin at a dose of either 10 or 20 mg/kg for 7 weeks, beginning 1 week after diabetes induction. Vascular permeability was estimated by measuring Evans blue dye extravasation. Oxidative stress markers, including malondialdehyde (MDA) and superoxide dismutase (SOD) activity, were also measured in aortic tissue. Results: Extravasation of Evans blue dye increased significantly in the diabetic group compared to that in the control group (p < 0.05), and treatment with sesamin significantly and dose-dependently decreased this extravasation (p < 0.05). Diabetic rats also had elevated malondialdehyde (MDA) and reduced superoxide dismutase (SOD) activity (p < 0.005–0.001), and chronic treatment with sesamin (20 mg/kg) significantly reversed the elevated MDA content (p < 0.05) and reduced SOD activity (p < 0.05). Conclusions: Chronic treatment of diabetic rats with sesamin could dose-dependently improve aortic permeability, partly through the attenuation of oxidative stress in aortic tissue. A R T I C L E I N F O Article history: Received: 02 Dec 2010 Revised: 10 Dec 2010 Accepted: 02 Jan 2011