Hyperglycemia potentiates collagen-induced platelet activation through mitochondrial superoxide overproduction. Diabetes 2001;50:1491–1494

Alteration of platelet function contributes to micro-thrombus formation and may play an important role in the pathogenesis of diabetic micro- and macroangiopa-thies. However, the molecular mechanism for platelet dysfunction observed in patients with diabetes has not been fully elucidated. In this study, the direct effects of hyperglycemia on platelet function in vitro were inves-tigated. Hyperglycemia increased reactive oxygen spe-cies generation in human platelets, and this effect was additive with that of collagen. Thenoyltrifluoroacetone (TTFA), an inhibitor of mitochondrial electron trans-port chain complex II, and carbonyl cyanide m-chloro-phenylhydrazone (CCCP), an uncoupler of oxidative phosphorylation, completely prevented the effects of hyperglycemia, suggesting that reactive oxygen specie