NFE2L2 and Cerebral ischemia: To systematically explore the protective effects of Nrf2 in different stages of cerebral ischemia, we review its role according to the chronological order, including ischemic preconditioning (IPC) before the occurrence of ischemia, at the stage of I/R and the long-term prognosis after I/R, in order to introduce the role of Nrf2 in cerebral I/R in detail.