Turkish Journal of Medical Sciences




Aim: The association between oxidative stress and diabetic complications is well known. The main goal of antidiabetic therapy is to prevent the complications of diabetes. Gliclazide (sulfonylurea) and metformin (biguanide) are two oral antidiabetic drugs that have been proven to prevent diabetic complications. In this study, we aimed to investigate the antioxidant effects of gliclazide or metformin. Materials and Methods: In this study, we evaluated 46 patients with type 2 diabetes mellitus. The patients were divided into three groups according to their treatment modality of gliclazide, metformin, or diet. Erythrocyte glutathione peroxidase (Gpx), glutathione S-transferase (GST), and catalase (CAT) activities and malondialdehyde (MDA) and glutathione (GSH) levels of the patients were measured and compared. Results: The erythrocyte Gpx, GST, and CAT activities were significantly higher, whereas MDA levels were significantly lower in both gliclazide and metformin groups when compared with the diet group. There was no statistically significant difference between gliclazide and metformin groups in terms of activities of antioxidant enzymes and levels of MDA. In addition, GSH levels were not different among the groups. Conclusions: The data obtained in this study showed that gliclazide or metformin administration may decrease oxidative stress, and both drugs had similar effects.


Diabetes mellitus, gliclazide, metformin, antioxidant enzymes, malondialdehyde

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