Protective Effects of the Green Tea Polyphenol(-)-epigallocatechin Gallate Against Ischemia Reperfusion Injury Induced by Middle Cerebral Artery Occlusion in Rats

ABSTRACT

BACKGROUND: EGCG(epigallocatechin gallate), a major green tea extract, is a potent free radical scavenger which has been shown to reduce free radical-induced lipid peroxidation. The purpose of this study was to examine whether EGCG reduces focal ischemia/reperfusion-induced brain injury in rats. METHODS: Male Wistar rats were anesthetized with ketamine and xylazine and subjected to 120 min of temporary middle cerebral artery occlusion by an intraluminal nylon suture coated with poly-L-lysine. The drug (EGCG, n=8) or vehicle (normal saline, n=8) was administered iv.(as a 50 mg/kg bolus) immediately after the onset of middle cerebral artery occlusion. Neurologic status was evaluated 2 hours after occlusion and 24 hours after. Twenty-four hours after ischemia, the brain was perfusion-fixated and the infarct volume was determined. RESULTS: EGCG significantly improved the neurological status at 24 hours after middle cerebral artery occlusion.(p<0.05), and reduced total infarct volumes (p<0.01). CONCLUSIONS: These results demonstrate the neuroprotective effect of EGCG in a rat model of transient focal cerebral ischemia.