PTEN and brain ischemia: As a major negative regulator, PTEN has been confirmed to be involved in the activation of AKT signaling after cerebral ischemia and TBI (Liu et al., 2010; Ding et al., 2013; Guo et al., 2013; Kitagishi and Matsuda, 2013; Wang et al., 2013; Kilic et al., 2017; Xue et al., 2018), and PTEN phosphorylation could reduce the apoptosis of neurons and the permeability of BBB and may contribute to neuroprotection after TBI (Hasegawa et al., 2012; Ding et al., 2013; Kitagishi and Matsuda, 2013; Wang et al., 2013).