Abstract: Recent studies have shown that tea polyphenols can cross the blood-brain barrier,inhibit apoptosis and play a neuroprotective role against cerebral ischemia.Furthermore,tea polyphenols can decrease DNA damage caused by free radicals.We hypothesized that tea polyphenols repair DNA damage and inhibit neuronal apoptosis during global cerebral ischemia/reperfusion.To test this hypothesis,we employed a rat model of global cerebral ischemia/reperfusion.We demonstrated that intraperitoneal injection of tea polyphenols immediately after reperfusion significantly reduced apoptosis in the hippocampal CA1 region; this effect started 6 hours following reperfusion.Immunohistochemical staining showed that tea polyphenols could reverse the ischemia/reperfusion-induced reduction in the expression of DNA repair proteins,X-ray repair cross-complementing protein 1 and apurinic/apyrimidinic endonuclease/redox factor-1 starting at 2 hours.Both effects lasted at least 72 hours.These experimental findings suggest that tea polyphenols promote DNA damage repair and protect against apoptosis in the brain.