Decreased plasma α-synuclein in idiopathic Parkinson’s disease patients after adjusting hemolysis factor

Abstract

Background: Lewy bodies are pathological hallmarks for the diagnosis of Parkinson’s disease, where the core components are composed of aggregated forms of α-synuclein (α-syn). Although α-syn has been investigated as a potential biomarker for PD, its usage has been limited and still remains controversial. Objective: An accurate enzyme-linked immunosorbent assay (ELISA) was developed for the detection of α-syn in plasma. The hemolysis score was calculated to eliminate the additive α-syn levels from RBCs. Human plasma samples were collected in heparinized blood tubes from idiopathic Parkinson disease (IPD) and healthy control (HC). Result: Hemolysis score had a strong correlation with the level of plasma α-syn. From the limited set of samples in this preliminary study, decreased α-syn concentrations were observed in patients with IPD in comparison to HC after adjusting for hemolysis factor. Similar results with a commercial ELISA kit were found for measuring α-syn from the same set of samples with lower correlation and the reduced accuracy of diagnosis than the current study. Conclusion: The adjustments for the hemolysis factor would be indispensable, supporting plasma α-syn as a potential surrogate biomarker for distinguishing IPD from HC. © 2020, The Korean Society of Toxicogenomics and Toxicoproteomics 2020.