This theory was further validated in animal models, which found that cerebral ischemia in mice leads to a significant increase in SUMO2/3 conjugates in the hippocampus and cerebral cortex, and a neuroblastoma cell model undergoing hypoxia/glucose deprivation followed by a short period of reoxygenation under the same conditions also exhibits significant increases in SUMO2/3 conjugation (84, 85). This evidence concerns the gene SUMO2 and brain ischemia.