Protective effect of diphlorethohydroxycarmalol isolated from Ishige okamurae against high glucose-induced-oxidative stress in human umbilical vein endothelial cells.

In the present study, the protective effect of diphlorethohydroxycarmalol (DPHC) isolated from Ishige okamurae, a brown algae, on high glucose-induced-oxidative stress was investigated using human umbilical vein endothelial cells (HUVECs). High concentration of glucose (30 mM) treatment induced cytotoxicity whereas DPHC prevented cells from high glucose-induced damage; restoring cell viability was significantly increased. In addition, the lipid peroxidation, intracellular reactive oxygen species (ROS), and nitric oxide (NO) levels induced by high glucose treatment were effectively inhibited by addition of DPHC in a dose-dependent manner. DPHC also suppressed the over-expressions of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins as well as nuclear factor-kappa B (NF-kappaB) activation induced by high glucose in HUVECs. These finding indicate that DPHC might be used as potential pharmaceutical agent which will reduce the damage caused by high glucose-induced-oxidative stress associated with diabetes.