APP and Alzheimer disease: Evaluation of neuropathology in the brain of dimebon treated TgCRND8 mice showed that dimebon had no effect on contents of total Aβ or soluble oligomeric Aβ in the brain, further supporting the argument that dimebon does not directly target amyloid precursor protein (APP) processing or Aβ oligomerization which has been proposed to be responsible for cognitive dysfunction in AD [21-26].