TY - JOUR KW - A53T KW - Alpha-synuclein KW - Parkinson disease KW - Plasma KW - Serum TI - Peripheral alpha-synuclein levels in patients with genetic and non-genetic forms of Parkinson's disease SP - 35 UR - https://doi.org/10.1016/j.parkreldis.2020.03.014 EP - 40 JF - Parkinsonism & Related Disorders AV - public ID - discovery10099182 N1 - This version is the author accepted manuscript. For information on re-use, please refer to the publisher's terms and conditions. A1 - Emmanouilidou, E A1 - Papagiannakis, N A1 - Kouloulia, S A1 - Galaziou, A A1 - Antonellou, R A1 - Papadimitriou, D A1 - Athanasiadou, A A1 - Bozi, M A1 - Koros, C A1 - Maniati, M A1 - Vekrellis, K A1 - Ioannou, PC A1 - Stefanis, L VL - 73 Y1 - 2020/04// N2 - BACKGROUND: Variations of ?-synuclein levels have been reported in serum and plasma in Parkinson's Disease (PD) Patients. METHODS: Serum and plasma were obtained from PD patients without known mutations (GU-PD, n = 124)), carriers of the A53T/G209A point mutation in the ?-synuclein gene (SNCA) (n = 29), and respective age-/sex-matched controls. Levels of total ?-synuclein were assessed using an in-house ELISA assay. RESULTS: A statistically significant increase of ?-synuclein levels was found in serum, but not plasma, from GU-PD patients compared to healthy controls. A statistically significant decrease of ?-synuclein levels was found in serum and plasma from symptomatic A53T mutation carriers compared to healthy controls. Plasma ?-synuclein levels were modestly negatively correlated with UPDRS part III score and disease duration in A53T-PD patients. CONCLUSION: Increased ?-synuclein levels in serum of GU-PD patients suggest a systemic deregulation of ?-synuclein homeostasis in PD. The opposite results in A53T-PD highlight the complexity of ?-synuclein homeostatic regulation in PD, and suggest the possibility of reduced expression of the mutant allele. ER -