Abstract

Diabetes is a chronic disease cause the metabolic disorder and associated with serious complications. Various studies have shown that diabetes mellitus is associated with increased the formation of free radicals and decreased antioxidant potential. Oxidative stress is increased in diabetes because of multiple factors. Dominant among these factors is glucose autoxidation leading to the production of free radicals. Treatment with the antioxidants may play an important role in the improvement of diabetes. In this study, we aimed to determine the antioxidant and anti-hyperglycemic properties of Tithonia diversifolia aqueous leaves extract (TDA). The potential antioxidant was examined and the results showed that the total phenolic content and the total antioxidant capacity of TDA were 55.92 ± 4.45 GAE mg/g dry weight and 93.09 ± 37.91 μM TEAC/mg dry weight, respectively. The anti-hyperglycemic activity of TDA at dose 500 mg/kg BW were studied by oral glucose tolerance test (OGTT) in normal mice and were daily orally administrated in alloxan-induced diabetic mice for 4 weeks. Hypoglycemic effect of TDA at dose 500 mg/kg BW showed significantly reduced blood glucose level on OGTT in normal mice (P<0.05). Moreover, TDA treated alloxan-induced diabetes mice for 30 days significantly decreased blood levels of glucose, total cholesterol, triglyceride and low density lipoprotein-cholesterol (LDL-cholesterol) and increased high density lipoprotein-cholesterol (HDL-cholesterol). The malondialdehyde (MDA), the lipid peroxide product of oxidative marker, was improved in TDA-treated group. These results suggested that TDA exerts its antioxidant property by inhibiting the chain reaction of lipid peroxidation and acts as the hypoglycemic activity, reducing the blood glucose level in alloxan-induced diabetes mice. Toxicity and the mechanism of TDA should further study and development as dietary supplements for the treatment of type 2 diabetes.