TY - JOUR A1 - Migdalska-Richards, A A1 - Wegrzynowicz, M A1 - Rusconi, R A1 - Deangeli, G A1 - Di Monte, DA A1 - Spillantini, MG A1 - Schapira, AHV Y1 - 2017/10// IS - 10 TI - The L444P Gba1 mutation enhances alpha-synuclein induced loss of nigral dopaminergic neurons in mice KW - glucocerebrosidase KW - GBA1 KW - alpha-synuclein KW - Parkinson?s disease KW - neurodegeneration UR - https://doi.org/10.1093/brain/awx221 SP - 2706 VL - 140 N2 - Mutations in glucocerebrosidase 1 (GBA1) represent the most prevalent risk factor for Parkinson's disease. The molecular mechanisms underlying the link between GBA1 mutations and Parkinson's disease are incompletely understood. We analysed two aged (24-month-old) Gba1 mouse models, one carrying a knock-out mutation and the other a L444P knock-in mutation. A significant reduction of glucocerebrosidase activity was associated with increased total alpha-synuclein accumulation in both these models. Gba1 mutations alone did not alter the number of nigral dopaminergic neurons nor striatal dopamine levels. We then investigated the effect of overexpression of human alpha-synuclein in the substantia nigra of aged (18 to 21-month-old) L444P Gba1 mice. Following intraparenchymal injections of human alpha-synuclein carrying viral vectors, pathological accumulation of phosphorylated alpha-synuclein occurred within the transduced neurons. Stereological counts of nigral dopaminergic neurons revealed a significantly greater cell loss in Gba1-mutant than wild-type mice. These results indicate that Gba1 deficiency enhances neuronal vulnerability to neurodegenerative processes triggered by increased alpha-synuclein expression. EP - 2721 JF - Brain AV - public ID - discovery10025253 SN - 1460-2156 N1 - Copyright © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. ER -