Oxyresveratrol (trans-2,3',4,5'-tetrahydroxystilbene) is neuroprotective and inhibits the apoptotic cell death in transient cerebral ischemia

Oxidative stress is one of the major pathological factors in the cascade that leads to cell death in cerebral ischemia. Here, we investigated the neuroprotective effect of a naturally occurring antioxidant, oxyresveratrol, to reduce brain injury after cerebral stroke. We used the transient rat middle cerebral artery occlusion (MCAO) model of brain ischemia to induce a defined brain infarction. Oxyresveratrol was given twice intraperitoneally: immediately after occlusion and at the time of reperfusion. Oxyresveratrol (10 or 20 mg/kg) significantly reduced the brain infarct volume by approximately 54% and 63%, respectively, when compared to vehicle-treated MCAO rats. Also, the neurological deficits as assessed by different scoring methods improved in oxyresveratrol-treated MCAO rats. Histological analysis of apoptotic markers in the ischemic brain area revealed that oxyresveratrol treatment diminished cytochrome c release and decreased Caspase-3 activation in MCAO rats. Also, staining for apoptotic DNA showed that the number of apoptotic nuclei in ischemic brain was reduced after oxyresveratrol treatment as compared to the vehicle-treated MCAO rats. This dose-dependent neuroprotective effect of oxyresveratrol in an in vivo stroke model demonstrates that this drug may prove to be beneficial for a therapeutic strategy to limit brain injury in acute brain ischemia.