Using a model of focal cerebral ischemia in mice, Hayakawa et al. found that reactive astrocytes expressing HMGB1 increased in the peri-infarct cortex from day 7 after cerebral ischemia in parallel with the increase of neurovascular remodeling markers CD31, synaptophysin, and PSD95 [93]. Here, HMGB1 is linked to brain ischemia.