APP and Alzheimer disease: The hyperactivation of PI3K/Akt/mTOR resulted in decreased autophagy in the aluminum-induced AD rats’ brains, and the findings showed the restoration of this axis in MSC-derived exosomes together with the mTOR inhibitor group, as can be seen through increased autophagy activity along with decreased APP cleavage, increased proteolytic degradation of aβ and improved memory performance.