Indentification of Novel Biomarkers for Paroxysmal Non- Kinesigenic Dyskinesia Diagnosis Via Cerebrospinal Fluid and Plasma Proteomic Analysis

Purpose Paroxysmal non-kinesigenic dyskinesia (PNKD) is a rare autosomal dominant movement disorder characterized by spontaneous attacks. The purpose of this study was to find and analyze the differentially expressed proteins between PNKD patients and their healthy family members with matched age and gender, thus providing potential biomarkers for early diagnosis of patients with PNKD. Methods Four PNKD patients and four healthy family members were selected. Isobaric tags for relative and absolute quantitation (iTRAQ) coupled with LC-MS/MS were used to identify the differential proteins obtained from CSF and plasma of PNDK patients and healthy family members. Bioinformatic analyses of differential proteins were performed included Gene Ontology (GO) enrichment, pathway enrichment and protein-protein interaction network analysis. Results A total of 1242 and 512 unique proteins were identified in CSF and plasma respectively. The numbers of proteins that were differentially expressed between PNKD patients and their healthy family members were 42 in CSF and 57 in plasma respectively. Proteins that were differentially expressed were further analyzed based on bioinformatics. Two differentially expressed proteins in the CSF, CALML5 and PDGFA, and one in the plasma, ACTB, showed close links with the PNKD protein in the protein–protein interaction network. Conclusion CALML5 and PDGFA in the CSF and ACTB in the plasma may take part in PNKD pathogenesis and act as the potential biomarkers for PNKD diagnosis.