HMGB1 and subarachnoid hemorrhage: Several studies have demonstrated that HMGB1 can be transferred from the nucleus of the neuron to the cytoplasm or released extracellularly by stimulation such as brain ischemia (Qiu et al., 2008; Zhang et al., 2016; Chen et al., 2019) and subarachnoid hemorrhage (Sun et al., 2014).