CHRNA4 and Alzheimer disease: Cholinergic signaling, in particularα7 nAChR–dependent PI3K/AKT/GSK-3β pathway are critically involved in several disorders, including schizophrenia, stroke, Alzheimer's disease, myocardial ischemia reperfusion and experimental autoimmune encephalomyelitis and can provide protection against inflammatory injury (27, 47–52).