Detection and Assessment of α-Synuclein Oligomers in the Urine of Parkinson’s Disease Patients

Article type: Research Article

Authors: Nam, Daleum^a | Lee, Jee-Young^b | Lee, Minhyung^{c; d} | Kim, Janghwan^{c; d} | Seol, Wongi^a | Son, Ilhong^{a; e; *} | Ho, Dong Hwan^{a; *}

Affiliations: [a] InAm Neuroscience Research Center, Sanbon Medical Center, College of Medicine, Wonkwang University, Gunposi, Gyeonggido, Republic of Korea | [b] Department of Neurology, Seoul National University Boramae Medical Center, Seoul, Republic of Korea | [c] Stem Cell Convergence Research Center, Korea Research Institute of Bioscience and Biotechnology (KRIBB), Daejeon, Republic of Korea | [d] Department of Functional Genomics, KRIBB School of Bioscience, University of Science and Technology, Daejeon, Republic of Korea | [e] Department of Neurology, Sanbon Medical Center, College of Medicine, Wonkwang University, Gunposi, Gyeonggido, Republic of Korea

Correspondence: [*] Correspondence to: Dong Hwan Ho, InAm Neuroscience Research Center, Sanbon Medical Center, College of Medicine, Wonkwang University, Sanbonro 321, Gunposi, Gyeonggido, Republic of Korea. Tel.: +82 31 390 2410; Fax: +82 31 390 2414; E-mail: ethan2887@gmail.com; Ilhong Son, InAm Neuroscience Research Center, Sanbon Medical Center, College of Medicine, Wonkwang University, Sanbonro 321, Gunposi,Gyeonggido, Republic of Korea. Tel.: +82 31 390 2486; Fax: +82 31 390 2414; E-mail: sonih@wku.ac.kr.

Abstract: Background:α-Synuclein (α-syn) is a major component of Lewy bodies, a pathologic marker of Parkinson’s disease (PD) in post-mortem studies. The use of α-syn as a practical PD biomarker has been investigated by numerous researchers. However, reports of differences in α-syn levels in biofluids, such as cerebrospinal fluid, plasma, and saliva, between PD patients and controls are inconsistent. Recently, the measurement of α-syn oligomer levels has emerged as a novel approach to diagnose PD. Objective:Lysates and culture media from two different types of dopaminergic neuronal cells or urine samples from 11 non-PD and 21 PD patients were collected and analyzed. Methods:We developed and performed an enzyme-linked immuno-absorbent assay (ELISA) to detect various oligomeric α-syn using distinct pairs of antibodies. Results:We validated our ELISA using rotenone-induced alterations of α-syn levels in human dopaminergic neurons. Total urinary α-syn levels, measured using our ELISA method, showed no difference between PD and non-PD individuals, but a higher level of α-syn oligomer recognized by MJFR-14-6-5-2 in PD urine samples was observed. Levels of distinct oligomeric α-syn detected by ASyO5 were lower in PD urine samples. Three different α-syn ELISA results were analyzed with respect to the severity of PD, but only the correlation between total α-syn levels and PD index was significant. Conclusion:Our findings suggest that detection of distinct oligomeric formations of α-syn and measurement of their levels in urine might be feasible for use in PD diagnostics.

Keywords: Parkinson’s disease, α-Synuclein, ELISA, urine

DOI: 10.3233/JPD-201983

Journal: Journal of Parkinson's Disease, vol. 10, no. 3, pp. 981-991, 2020