Galangin, a dietary flavonoid, improves antioxidant status and reduces hyperglycemia-mediated oxidative stress in streptozotocin-induced diabetic rats.

To examine the effect of galangin on hyperglycemia-mediated oxidative stress in streptozotocin (STZ)-induced diabetic rats. Diabetes was induced by intraperitoneal administration of low-dose STZ (40 mg/kg body weight (BW)) into male albino Wistar rats. Galangin (8 mg/kg BW) or glibenclamide (600 µg/kg BW) was given orally, once daily for 45 days to normal and STZ-induced diabetic rats. Diabetic rats showed significantly increased levels of plasma glucose, thiobarbituric acid reactive substances, lipid hydroperoxides, and conjugated dienes. The levels of insulin and non-enzymatic antioxidants (vitamin C, vitamin E, reduced glutathione) and the activity of enzymatic antioxidants (superoxide dismutase, catalase, glutathione peroxidase, and glutathione-S-transferase (GST)) were decreased significantly in diabetic control rats. These altered plasma glucose, insulin, lipid peroxidation products, enzymatic and non-enzymatic antioxidants ions were reverted to near-normal level after the administration of galangin and glibenclamide. The present study shows that galangin decreased oxidative stress and increased antioxidant status in diabetic rats, which may be due to its antidiabetic and antioxidant potential.