Abstract: Objective To explore the effect of ashitaba chalcone(AC)on oxidative stress in type 2 diabetic rats.Methods Type 2 diabetic rat model was set up in male Wister rats by feeding high-fat diet and streptozotocin(STZ)injection.Rats in AC treatment groups(at dosages of 5,10,and 30 mg/kg)were treated with gavage AC daily.Four weeks later,the fasting blood glucose (FBG),insulin,superoxide dismutase(SOD),malondialdehyde(MDA),total antioxidative capacity(T-AOC),and oxidized low density lipoprotein(ox-LDL)were measured and the morphology of islet cellulars was observed.Results In diabetic model group,the levels of FBG(17.30±3.57 mmol/ml),insulin(38.28±4.97 mU/L),MDA (12.00±1.32 nmol/ml),and ox-LDL(23.05±2.87 ng/ml)were significantly elevated compared with those of the control group(P< 0.05 for all).In 30 mg/kg AC group,the levels of FBG (7.00±2.55 mmol/ml),insulin(29.50±5.31 mU/L),MDA (9.96±0.65 nmol/ml),and ox-LDL (15.36±1.70 ng/ml)were significantly lower than those of diabetic model group (P< 0.05 for all) and the magnitude of morphological damage in islets cellular was also alleviated.Conclusion Ashitaba chalcone could inhibit oxidative stress and injury of islet cells in type 2 diabetic rats.