INS and diabetes mellitus: Fifteen years later, Frölich et al. described alterations in neuronal insulin signal transduction pathways in AD brains (Frölich et al. 1998), leading to Hoyer’s proposal that AD could be considered a brain-specific form of non-insulin-dependent diabetes mellitus (Hoyer 1998) (with a later suggestion by de la Monte to name AD diabetes mellitus type 3 (Steen et al. 2005)).