While Alzheimer’s disease (AD) is considered primarily as a disease of the central nervous system (CNS) representing the leading cause of dementia, it is accompanied by metabolic dysfunction and insulin resistance in the brain and peripheral tissues that have been long recognized as pivotal features of type 2 diabetes mellitus (DM) (Zhao and Townsend, 2009; Arnold et al., 2018; Rhea et al., 2022; Ezkurdia et al., 2023). Here, INS is linked to type 2 diabetes mellitus.