CDK5 and Alzheimer disease: Activation of PKA, CaMKII, GSK‐3β and cdk5 in T2DM leads to the hyperphosphorylation of tau, aggregation of tau proteins and formation of NFTs seen in AD (Dolan & Johnson, 2010; Duka et al., 2013; Engin & Engin, 2021; Wang et al., 2007).