Analysis of α-synuclein levels related to LRRK2 kinase activity: from substantia nigra to urine of patients with Parkinson's disease

• Published in: Animal cells and systems Vol. 25; no. 1; pp. 28 - 36
• Main Authors: Nam, Daleum, Kim, Ami, Han, Sun Jung, Lee, Sung-Ik, Park, Sung-Hye, Seol, Wongi, Son, Ilhong, Ho, Dong Hwan
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 02.01.2021; Taylor & Francis Ltd; Taylor & Francis Group; 한국통합생물학회
• Subjects: Antibodies; Cell differentiation; Developmental stages; Diagnostic software; disease progression; Drug development; ELISA; Enzyme-linked immunosorbent assay; extracellular space; humans; Kinases; Leucine; leucine-rich repeat kinase 2; LRRK2 protein; Lysates; Markers; Monomers; Movement disorders; Mutation; Neurobiology & Physiology; Neurodegenerative diseases; Oligomers; PARK7 protein; Parkinson's disease; secretion; Substantia nigra; Synuclein; therapeutics; Urine; α-synuclein; 생물학; leucine-rich repeat kinase 2; Parkinson’s disease; α-synuclein; ELISA
• ISSN: 1976-8354; 2151-2485; 2151-2485
• DOI: 10.1080/19768354.2021.1883735

Research on Parkinson's disease (PD) has been focused on the development of PD diagnostic tools as much as the development of PD therapeutics. Several genetic culprits of PD, including DJ-1, Leucine-rich repeat kinase 2 (LRRK2), and α-synuclein (α-syn), have been investigated as markers of PD in human biofluids. Unfortunately, the approaches to develop PD diagnostic tools are impractical, and there is a considerable demand for an appropriate marker of PD. The measurement of α-syn in biofluids has recently been made more accurate by examining monomers and aggregates separately using enzyme-linked immunosorbent assay (ELISA). Previously, we reported on the development of two types of sandwich ELISA for total α-syn and MJFR-14-6-4-2 antibody-specific α-syn fibrillar oligomers. The pathogenic LRRK2 G2019S mutation is related to increased α-syn secretion in the extracellular space. We tested our established ELISA using differentiated SH-SH5Y cells transfected with LRRK2 G2019S. The secretory levels of fibrillar oligomeric α-syn divided by total α-syn were significantly increased in LRRK2 G2019S-expressing cells. Additionally, substantia nigra lysates or concentrated urine from PD patients and non-PD subjects were analyzed. We observed ambiguous changes in the levels of total or fibrillar oligomeric α-syn and their ratio between PD and non-PD. Despite the insignificant increase in the relative levels of fibrillar oligomeric α-syn to total α-syn in PD, the duration of disease progression after diagnosis significantly corresponded to the relative levels of fibrillar oligomeric α-syn to total α-syn in the urine. These results might provide greater understanding for the next stage of development of α-syn ELISAs.