Preliminary Screening Disease-Specific Proteins Of Parkinson's Disease

Objective: Comparing the two-dimensional gel electrophoresis (2D-PAGE) with cerebrospinal fluid(CSF) of Parkinson's Disease patients and controls (patients with essential tremor ,Multiple system atrophy and patients with headache), to find out the differentially expressed proteins which were closely correlated with Parkinson's Disease. According to these, biomarkers to diagnose PD were selected.Methods: proteins extracted from CSF were run in immobilized pH gradient isoelectic focusing (IPG-IEF) at the first dimension, and then run in in vertical flat sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) at the second dimension. The protein spots in gels were visualized by silver staining protocol, and the gels were scanned .And then, the gels were analysised by Pdquest 8.0.The differentially displayed protein spots were searche and identifiyed by MALDI-TOF-MS.And one of the differential proteins which is significant different one was then analyzed by enzyme-linked immunosorbent assay (ELISA).Results: 2D-PAGE images of PD and controls were acquired. Six DSPs were found out by Pdquest 8.0 software analyzing and mass spectrometric analying.They are fubiquitin protein ligase,Apolipoprotein E (Apo-E),NADH-ubiquinone oxidoreductase ASHI subunit,glial fibrillary acidicprotein (GFAP), Protein-tyrosine phosphatase 1B (PTP-1B) , Apolipoprotein A-I precursor(Apo-A1). The differential proteins E3,Apo-E and NADH-ubiquinone oxidoreductase ASHI subunit in CSF from patients with PD and MAS were down regulation compared with which in CSF from patients with ET and headache,and the remained three proteins were up regulation in CSF from patients with PD compared ET, MSA and headache. The ELISA analysis of protein Apo-E showed the same result of proteomics analysis.Conclusion: There were some differential protein spots in 2D-PAGE gels of Parkinson's disease and controls. Six differential protein spots were found, which are involved in oxidative stress, protein degradation, neurotrophy and reparation of nerves. These proteins were closely related to PD, they maybe the DSPs of PD and maybe take as biomarker of PD. The ELISA analysis of protein Apo-E showed the same result of proteomics analysis.This indicated that proteomics could be used to analyse CSF of patient with PD and the result was confidence.