Proteomic Comparison Between Normal Elderly And AD Patients In Frontal Lobe Tissues

Alzheimer's disease(AD) is one of the most nomal dementias.A lot of work to identify the pathogenetic and pathologic progress of AD have been done by investigators in many countries using brain tissues of people,animal models and cell models.Now in China there is no study about proteomic of AD brain of people.We carried the study in the Geronotlogical Research Center of the general hospital of PLA with the samples conserved in paraffin wax and in refrigerator at -80℃.The study included three parts:1)we selected the samples of AD and samples of control by HE stain and immunohistochemistry stain.Combining the clinical diagnosis,we designed the two groups after we obtained the pathologic diagnosis; 2) we isolated proteins of the two groups(AD group and control group) by fluorescence two-dimensional differential gel electrophoresis(2D-DIGE).Then identified the proteins by mass spectrometry and analyzed the association between the AD pathogenesy and the proteins.3)at the end,we validated part of the altered proteins by western blotting.The first part:pathobiology.Anti-β-Amyloid,anti-AT8,anti-Ubiquitin were used to obtain the AD samples and contol samples,which are the most common antibodies admitted by people to characterize the AD's pathological changes.We used anti-Synuclin to exclude Lewy' body dementia and Parkinson's dementia. With all these pathological changes we at length defined two groups:AD group and control group with each group including 6 cases.The second part:proteom study.After extracted protein from the cases of two groups,we ran the 2D-DIGE.The protein spots were analyzed by softwares of Image Master 2D Platinum,Image Quant and DeCyder(Version6.5) and then were identified by mass spectrometry.After searching in IPI HUMAN(v3.23) database,we obtained 14 different proteins.The different proteins are of oxidation, energy-related enzymes,and chaperonin et al.4 of the proteins have not been reported before in the studies of other investigators.Some alteration of protein level didn't correspond with that of the previous studies. The third part of the study was to validate the results of 2D-DIGE with western blotting.We detected the altered level of HSP90αand the two results corresponded.This demonstrated the stability and reliability of the 2D-DIGE.This study leads a new road to ascertain the pathogenesy of AD,and to find new diagnosis and therapy methods to AD.