PRNP and Alzheimer disease: Though the amyloid β (Aβ) protein is commonly placed in the center of AD aetiology, the scientific community has been conducting research to link Aβ with many other molecular players and processes known to contribute to disease development and progression, including the cellular prion protein (PrPC) [6], tau hyperphosphorylation [7], oxidative stress, neuroinflammation [8], and insulin resistance [9], among others.