Assessments of the accumulation severities of amyloid β-protein and hyperphosphorylated tau in the medial temporal cortex of control and Alzheimer's brains

Alzheimer's disease (AD) is characterized neuropathologically by neuritic plaques (NPs), and neurofibrillary tangles (NFTs). So far, the following key issues are not yet answered to the disease: (1) the accumulation degrees of three Aβ variants, and tau phosphorylation epitopes in AD as compared to control; (2) the correlation degrees of levels of three Aβ variants with different tau phosphorylation epitopes; (3) the correlation degrees of levels of three Aβ variants and different tau phosphorylation epitopes with Braak and CERAD staging systems. To address these issues, levels of Aβ40, Aβ42, and Aβ43, and phosphorylated tau were assessed by dot blots in homogenates of the medial temporal cortex from AD and control brains in the present study. These data implied different roles of tau phosphorylation epitopes in formation of NFTs, and in this process, Aβ might play a key role. Assessments of levels of these abnormal proteins by dot blots may serve as a useful complement to the morphological evaluations in diagnosis of AD.