Protective effect of quercetin on hyperglycemia, oxidative stress and DNA damage in alloxan induced type 2 diabetic mice

Aims: Quercetin is a natural polyphenolic flavonoid and acts as a quencher for reactive oxygen species generated by any physical or chemical action. In type 2 diabetes mellitus (T2DM) the basic characteristic feature is hyper-glycemia which leads to complications involving oxidative stress. In view of this, the present study was conducted to examine the effect of quercetin in T2DM. Main methods: A total of 18 mice were divided into three groups, vis control, diabetic and diabetic treated with quercetin. Fasting blood glucose (FBG) levels and anti-oxidant enzyme activity were assayed. Creatinine, urea, lipid peroxidation, GLUT4 expression and DNA damage were also measured. Key findings: A significant decrease in FBG level and liver and kidney marker enzymes was observed in the quercetin treated group as compared to the diabetic one. Glutathione, SOD, catalase, and glutathione-S-transferase levels were also found to be increased on quercetin supplementation. Thiobarbituric acid-reactive substance level was decreased while GLUT4 expression levels were increased in the treated group. DNA damage was also affected positively by quercetin when subjected with single cell alkaline gel electrophoresis. Thus, we may suggest an anti-oxidant potential and protective effect of quercetin in T2DM mice. Significance: From this study, we conclude that quercetin ameliorates hyperglycemia and oxidative stress, by blunting free radical induced toxicity in T2DM. (C) 2014 Elsevier Inc All rights reserved.