INS and early-onset autosomal dominant Alzheimer disease: The AKT pathway is one of several insulin signaling pathways, and its overactivation has been related to aggravation of Alzheimer’s disease pathology.57 In PD, the AKT pathway is altered, causing an overexpression of GSK-3β that enhances the formation of neurofibrillary tangles, which may in turn contribute to PD dementia.58 As the global burden of T2DM increases sharply, it becomes increasingly important to understand its potential role in neurodegeneration.59