Proteomic analysis of plasma from a Tau transgenic mouse.

The neurofibrillary tangles (NFTs) formed by the accumulation of abnormal tau filaments have been shown to be involved in Alzheimer's disease (AD) brain degeneration. In this study, a tau transgenic mouse (pNSE/htau23) model was used to monitor changes in protein levels and to search for novel biomarker candidates suitable for the early diagnosis of AD before onset of clinical symptoms. Plasma samples from 2-month (n=13, asymptomatic) and 4-month (n=7, symptomatic) tau transgenic mice were compared to the control group (n=8) by 2-dimensional gel electrophoresis (2-DE) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS). Three proteins, ATP synthase, Adenosine kinase and Regucalcin showed significantly decreased levels in the plasma of tau transgenic mouse, which was further confirmed by Western blotting. This study suggests that these proteins could be used as candidate biomarkers for early diagnosis of AD in combination with previously discovered protein biomarkers.