Neuroprotective effects of an antioxidant in cortical cerebral ischemia: prevention of early reduction of the apurinic/apyrimidinic endonuclease DNA repair enzyme

We examined the effects of the free radical scavenger, 21-aminosteroid, on apurinic/apyrimidinic endonuclease (APE/Ref-1) protein expression and subse quent infarction volume after photothrombotic cortical cerebral ischemia in mice. Immunohistochemistry and Western blot analysis showed a significant reduction in APE/Ref-1 expression 6 and 24 h after ischemia in untreated an imals, whereas in drug-treated animals the reduction was much less at the s ame time points. The administration of 21-aminosteroid significantly decrea sed subsequent infarction volume 3 days after ischemia. These data suggest that 21-aminosteroid prevents the early decrease of APE/Ref-1 expression, t hereby reducing cortical infarction after photothrombotic cerebral ischemia . (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.