MAPK8 and Alzheimer disease: In fact, GSK-3β is activated, along with caspases, during NGF deprivation-induced cell death of PC12 cells [129], Aβ- toxicity and oxidative stress [152] by a mechanism mediated by reduced PI3K/Akt signaling and JNK/p53 activation, thus providing a link between NGF deprivation and the two pathological components of AD.