Screening and identification of specific serum biomarkers of Parkinson disease

AIM：To screen the possible serum biomarkers of Parkinson’s disease. METHODS：The surface-enhanced laser desorption ionization time-of-flight mass spectrometry (SELDI-TOF-MS) was used to screen the serum samples from 44 cases of Parkinson’s disease and 60 control subjects. The differentially expressed protein peaks were selected and isolated with high-performance liquid chromatography (HPLC), and processed with enzyme before analysis by liquid chromatography-mass spectrometry tandem mass spectrometry (LC-MS/MS). The data mining was performed by Xcalibur program component BioWorks 3.2. RESULTS：Three differentially expressed protein peaks were selected as potential serum biomarkers from the patients of Parkinson’s disease: the protein at 8 937 m/z peak showed significant increase (27.47±16.58 in Parkinson’s disease group, and only 5.01±3.47 in control group), and the proteins at 6 636 and 8 697 m/z peaks showed significant decreases (5.43±2.66 and 20.22±9.57, respectively, in Parkinson’s disease group, and 18.85±7.56 and 51.13±26.22, respectively, in control group). The proteins at 6 636, 8 697 and 8 937 m/z peaks were identified as apolipoprotein C-I, apolipoprotein C-III and complement 3a,respectively. Combined use of these 3 biomarkers effectively distinguished the subjects between Parkinsons disease group and control group. The detection rate of the patients with Parkinsons disease was 90.0% (27/30), and the detection rate of the healthy sibkects was 92.5% (37/40). CONCLUSION：The apolipoprotein C-I, apolipoprotein C-III and complement component 3a identified as potential markers of Parkinson’s disease have diagnostic value in clinical application.