Troglitazone has a scavenging effect on reactive oxygen species

Troglitazone (CS-045), a newly developed antidiabetic thiazolidinedione that enhances insulin sensitivity, is similar in structure to several antioxidants, including alpha-tocopherol and probucol. The in vitro antioxidant activity of troglitazone has been demonstrated in alloxan-induced hyperlipoperoxidemic and hyperlipidemic mice. In this study, we found that troglitazone had a scavenging effect on reactive oxygen produced by xanthine-xanthine oxidase and generated by stimulated neutrophils and tends to be the radical form. Our results suggest that troglitazone is an antioxidant similar to alpha-tocopherol. However, under the same conditions, pioglitazone, another thiazolidinedione drug, did not have a scavenging effect. The antioxidant action of troglitazone, which is attributable to the similarity of its molecular structure to that of alpha-tocopherol, may be of benefit in preventing diabetic vascular complications, in addition to having hypoglycemic and hypolipidemic effects. (C) 1997 Academic Press.