Get access

Metformin decreases platelet superoxide anion production in diabetic patients




Patients with type 2 diabetes mellitus are usually treated with oral antidiabetic agents but it is still not known whether these drugs have antioxidant effects in humans.


We studied 60 patients with type 2 diabetes mellitus, divided into three groups on the basis of hypoglycaemic treatment (Group A: metformin, Group B: glibenclamide, Group C: diet). All patients were followed for at least 1 year. The three subgroups had similar clinical characteristics. Twenty healthy subjects, of comparable sex and age, were enrolled as controls. In each subject, platelet production of superoxide anion (O2) elicited by collagen, was determined by lucigenin assay.


Patients with diabetes had higher platelet O2 production than controls; no correlation was observed between blood glucose and platelet O2 production. Group A patients had platelet O2 production similar to that of healthy subjects but lower than Group B and Group C patients.


The present findings suggest an in vivo antioxidant activity of metformin and warrant prospective studies to further explore this hypothesis. Copyright © 2002 John Wiley & Sons, Ltd.