Alzheimer's disease is the most prevalent neurodegenerative disease, characterized by the presence of extensive extracellular amyloid plaques , intracellular neurofibrillary tangles, and synaptic loss, neuronal death in cerebral cortex and hippocampus, along with progressive impairment of cognition and emotional activities. Despite some clinical trials with encouraging results, no curative therapy for this disease has so far been developed. Increasing evidences shown that P-amyloid(Ap) deposition is the lea...