Antihyperglycemic and Antioxidant Effect of Ginger Extract on Streptozotocin-Diabetic Rats

Abstract

The present study was carried out to investigate the antidiabetic and antioxidant potentials of ginger (Zingibar Officinale) on Streptozotocin (STZ)-induced diabetic rats. An aqueous extract of raw ginger was administrated daily (0.5 g/kg, orally) for a period of 60 days to STZ-induced diabetic rats. At the end of the experiment, blood samples, plasma and erythrocytes were separated from part of the blood samples and Fasting plasma blood glucose and serum total cholesterol, Low Density Lipoprotein Cholesterol (LDL-cholesterol), High Density Lipoprotein Cholesterol (HDL-cholesterol), triglyceride where analyzed. Changes in plasma total antioxidant capacity and Malondialdehyde (MDA) were measured. The activities of erythrocytes Super-oxide Dismutase (SOD) and blood Glutathione Peroxidase (GSH-Px) were determined. The STZ-diabetic rats exhibited hyperglycemia accompanied with weight loss. Ginger extract, at a dose of 0.5g/kg, was significantly (P<0.05) effective in lowering plasma glucose, total cholesterol, LDL-cholesterol and triglyceride levels in the ginger-treated diabetic rats compared with the control diabetic rats. Furthermore, ginger treatment resulted in a significant (P<0.05) reduction in plasma malondialdehyde. On the other hand, ginger extract significantly (P<0.05) increased plasma total antioxidant capacity and the activities of SOD and GSH-Px enzymes. This study demonstrates that ginger possesses hypoglycemic, hypocholesterolemic and hypolipidemic potentials in STZ-diabetic rats. Additionally, ginger extract causes a decrease in lipid peroxidantion and an increase of plasma antioxidant capacity.