Identification of non-Alzheimer's disease tauopathies-related proteins by proteomic analysis

Objectives: To identify differentially expressed proteins between tauopathies cases and controls and to explore molecular mechanisms of tauopathies. Method: Two-dimensional gel electrophoresis (2DE) was applied to separate the total proteins of temporal lobe obtained at autopsy from four tauopathies cases and four aged subjects without clinical or pathologic involvement of nervous system. The silver or Coomassie brilliant blue stained gels were analysed by 2-DE software Image Master 2D Elite. Selected differential protein spots were identified with MALDI-TOF/TOF tandem mass spectrometry. Results: Glyceraldehyde 3-phosphate dehydrogenase, uracil DNA glycosylase, human superoxide dismutase, isocitrate dehydrogenase subunit, synaptotagmin I, thioredoxin peroxidase 1, glial fibrillary acidic protein, P25 alpha, enoyl coenzyme A hydratase short chain 1, pyridoxine-5'- phosphate oxidase, Mn-superoxide dismutase and alpha enolase were significantly up-regulated in tauopathies brains, whereas antioxidant protein 2, ferritin heavy chain, glutamate dehydrogenase precursor, peptidyl-prolyl cis-trans isomerase A, serum albumin precursor and dihydropyrimidinase-related protein 2 were lowly expressed in tauopathies brains. Conclusions: We identified a number of tauopathy-related proteins that might be useful for discovering the molecular mechanisms of tauopathies, which could also be helpful for diagnosing and treating these disorders.