[The expression of DJ-1 protein in proteomic analysis of late-onset Alzheimer disease].

OBJECTIVE

To investigate the pathogenicity of late-onset Alzheimer disease from the viewpoint of comparative proteomic technology and to screen it from diseases with related protein markers.

METHODS

Cerebral cortex tissue of temporal layer of 8 cases of late-onset Alzheimer disease and 5 cases of age-matched autopsied controls with normal brain was chosen for this study. Cerebral proteins were run through immobilized pH gradient (IPG) isoelectric focusing electrophoresis as the first dimension and then vertical SDS-PAGE electrophoresis as the second dimension. Differential proteins were identified with visionworks LS and then analyzed with matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS) and electrospray ionization mass spectrometry (ESI-MS). Finally, the protein was identified by searching in the data bank.

RESULTS

Different 2-dimensional gel electrophoresis maps were obtained for the protein spots in the late-onset Alzheimer disease group and the control group gels.11 protein spots showed a significantly differential expression between the two groups of cerebral cortex samples. It was found that the expression of DJ-1 protein was increased in the late-onset Alzheimer disease group in comparison with the control group after searching in the database.

CONCLUSION

DJ-1 protein may be a potential marker related to Alzheimer disease pathogenicity. This finding would be helpful to develop new drugs which focus on this protein and prevent neurodegeneration.