Protective effects of enzymatic digest from Ecklonia cava against high glucose-induced oxidative stress in human umbilical vein endothelial cells.

Abstract

Antioxidants can prevent pathological damage caused by hyperglycaemia-induced oxidative stress associated with diabetes. In the present study, we investigated whether the brown alga Ecklonia cava has protective effects against high glucose-induced oxidative stress in Human umbilical vein endothelial cells (HUVECs). For that purpose, we prepared an enzymatic digest from E. cava (ECC) by using the carbohydrate, Celluclast. High glucose treatment induced HUVECs cell death, but ECC, at a concentration of 10 or 100 microg mL(-1), significantly inhibited the high glucose-induced cytotoxicity. Furthermore, treatment with ECC dose-dependently decreased thiobarbituric acid reactive substances (TBARS), intracellular generation of reactive oxygen species, and the nitric oxide level increased by high glucose. In addition, ECC treatment increased activities of antioxidant enzymes including catalase, superoxide dismutase and glutathione peroxidase in high-glucose pretreated HUVECs. High glucose levels induced the overexpression of inducible nitric oxide synthase, cyclooxygenase-2 and nuclear factor-kappa B proteins in HUVECs, but ECC treatment reduced the overexpression of these proteins. These results suggest that ECC is a potential therapeutic agent that will reduce the damage caused by hyperglycaemia-induced oxidative stress associated with diabetes.