Proteomic Analysis of the Cerebrospinal Fluid of Parkinson's Disease Patients Pre- and Post-Deep Brain Stimulation

Abstract

Aims: To investigate alterations in protein expression associated with deep brain stimulation (DBS) in an attempt to elucidate possible mechanisms of action. Methods: Cerebrospinal fluid (CSF), obtained from six Parkinson's disease (PD) patients (pre- and post-DBS) and from six normal healthy controls, was studied for differentially expressed proteins. 2-D DIGE, in combination with MALDI-TOF and TOF-TOF Mass Spectrometry (MS) or ESI-MS, was used to identify the changed proteins (3 PD patients and 3 controls). Selected proteins were further studied using western blotting (6 PD patients and 6 controls). Results: Twenty-one proteins were identified after MS and protein database interrogation. Apart from apolipoprotein A-I (apoA-I), the expression levels of complement C4 (C4), IgA, tetranectin, and extracellular superoxide dismutase (EC-SOD), detected by western blotting, correlated well with the 2-D DIGE results. In the follow-up period, the expression levels of C4, apoA-I and IgA were stable whereas EC-SOD and tetranectin were significantly elevated. In addition, when DBS was ceased in one patient due to a suicide attempt, the levels of EC-SOD and tetranectin significantly decreased. Conclusion: Our preliminary results suggest that variations in the expression levels of EC-SOD and tetranectin in CSF is related to DBS.