LTP and memory impairment caused by extracellular Aβ and Tau oligomers is APP-dependent

The concurrent application of subtoxic doses of soluble oligomeric forms of human amyloid-beta (oA beta) and Tau (oTau) proteins impairs memory and its electrophysiological surrogate long-term potentiation (LTP), effects that may be mediated by intra-neuronal oligomers uptake. Intrigued by these findings, we investigated whether oA beta and oTau share a common mechanism when they impair memory and LTP in mice. We found that as already shown for oA beta, also oTau can bind to amyloid precursor protein (APP). Moreover, efficient intra-neuronal uptake of oA beta and oTau requires expression of APP. Finally, the toxic effect of both extracellular oA beta and oTau on memory and LTP is dependent upon APP since APP-KO mice were resistant to oA beta- and oTau-induced defects in spatial/associative memory and LTP. Thus, APP might serve as a common therapeutic target against Alzheimer's Disease (AD) and a host of other neurodegenerative diseases characterized by abnormal levels of A beta and/or Tau.