Amyloid P component as a plasma marker for Parkinson's disease identified by a proteomic approach.

Parkinson's disease (PD) ranks the second among the neurodegenerative disorders. Proteins involved in Parkinson's disease (PD) have been investigated but none as the diagnostic markers in blood.In this study, we applied a proteomic strategy, by utilizing two-dimensional electrophoresis and mass spectrometry, to analyze two sample pools of plasma from the healthy individuals and PD subjects.IgGκL and human serum amyloid P component (SAP) were found differentially expressed between these pools. SAP level increased by approximately 5-fold in PD samples, and the ELISA procedure revealed a significant (P<0.001) increase in SAP concentration (65.9 ± 18.7μg/mL) in the plasma of PD subjects (healthy individuals, 35.0 ± 12.5μg/mL), with sensitivity of 94.1% and specificity of 87.5%.Our results indicated a potential feasibility of plasma SAP as a marker to approach PD.