PPIB and Alzheimer disease: Although autopsy-based studies have shown that T2DM is linked to cerebral infarcts (Peila et al., 2002; Arvanitakis et al., 2006; Sarwar et al., 2010), its association with AD neuropathology itself (i.e., β-amyloid plaques, Aβ and neurofibrillary tangles, NFT) remains unclear.