Edaravone, a free radical scavenger, attenuates cerebral infarction and hemorrhagic infarction in rats with hyperglycemia

Background: Thrombolysis due to acute ischemic stroke is associated with the risk of hemorrhagic infarction, especially after reperfusion. Recent experimental studies suggest that the main mechanism contributing to hemorrhagic infarction is oxidative stress caused by disruption of the blood-brain barrier. Edaravone, a free radical scavenger, decreases oxidative stress, thereby preventing hemorrhagic infarction during ischemia and reperfusion. In this study, we investigated the effects of edaravone on hemorrhagic infarction in a rat model of hemorrhagic transformation. Methods: We used a previously established hemorrhagic transformation model of rats with hyperglycemia. Hyperglycemia was induced by intraperitoneal injection of glucose to all rats (n = 20). The rats with hyperglycemia showed a high incidence of hemorrhagic infarction. Middle cerebral artery occlusion (MCAO) for 1.5 hours followed by reperfusion for 24 hours was performed in edaravone-treated rats (n = 10) and control rats (n = 10). Upon completion of reperfusion, both groups were evaluated for infarct size and hemorrhage volume and the results obtained were compared. Results: Edaravone significantly decreased infarct volume, with the average infarct volume in the edaravone-treated rats (227.6 mm(3)) being significantly lower than that in the control rats (264.0 mm(3)). Edaravone treatment also decreased the postischemic hemorrhage volumes (53.4 mm(3) in edaravone-treated rats vs 176.4 mm(3) in controls). In addition, the ratio of hemorrhage volume to infarct volume was lower in the edaravone-treated rats (23.5%) than in the untreated rats (63.2%). Conclusion: Edaravone attenuates cerebral infarction and hemorrhagic infarction in rats with hyperglycemia.