TNF and Cerebral ischemia: Microglia showed coarse process branch cells or fine process deformation cells, indicating that these two types of glial cells were activated after ischemic injury.[15] In cerebral ischemic brain tissue, activated microglia can produce pro‐inflammatory cytokines, such as interleukin‐1β (IL‐1β), interleukin‐6 (IL‐6), and tumor necrosis factor α (TNF‐α).[16] Although the primary purpose of activating microglia is to protect neuronal cells, microglial overactivation can lead to harmful inflammation and neuronal death.[17] The activation is extensive and persistent during cerebral ischemia.