N370S-GBA1 Mutation Causes Lysosomal Cholesterol Accumulation in Parkinson's Disease

Autor: Garcia-Sanz, P, Orgaz, L, Bueno-Gil, G, Espadas, I, Rodriguez-Traver, E, Kulisevsky, J, Gutierrez, A, Davila, JC, Gonzalez-Polo, RA, Fuentes, JM, Mir, P, Vicario, C, Moratalla, R
Rok vydání: 2017
Předmět:
Zdroj: MOVEMENT DISORDERS
r-IIB SANT PAU. Repositorio Institucional de Producción Científica del Instituto de Investigación Biomédica Sant Pau
instname
ISSN: 0885-3185
Popis: Background: Heterozygous mutations in the GBA1 gene, which encodes the lysosomal enzyme beta-glucocerebrosidase-1, increase the risk of developing Parkinson's disease, although the underlying mechanisms remain unclear. The aim of this study was to explore the impact of the N370S-GBA1 mutation on cellular homeostasis and vulnerability in a patient-specific cellular model of PD. Methods: We isolated fibroblasts from 4 PD patients carrying the N370S/wild type GBA1 mutation and 6 controls to study the autophagy-lysosome pathway, endoplasmic reticulum stress, and Golgi apparatus structure by Western blot, immunofluorescence, LysoTracker and Filipin stainings, mRNA analysis, and electron microscopy. We evaluated cell vulnerability by apoptosis, reactive oxygen species and mitochondrial membrane potential with flow cytometry. Results: The N370S mutation produced a significant reduction in beta-glucocerebrosidase-1 protein and enzyme activity and beta-glucocerebrosidase-1 retention within the endoplasmic reticulum, which interrupted its traffic to the lysosome. This led to endoplasmic reticulum stress activation and triggered unfolded protein response and Golgi apparatus fragmentation. Furthermore, these alterations resulted in autophagosome and p62/SQSTM1 accumulation. This impaired autophagy was a result of dysfunctional lysosomes, indicated by multilamellar body accumulation probably caused by increased cholesterol, enlarged lysosomal mass, and reduced enzyme activity. This phenotype impaired the removal of damaged mitochondria and reactive oxygen species production and enhanced cell death. Conclusions: Our results support a connection between the loss of beta-glucocerebrosidase-1 function, cholesterol accumulation, and the disruption of cellular homeostasis in GBA1-PD. Our work reveals new insights into the cellular pathways underlying PD pathogenesis, providing evidence that GBA1-PD shares common features with lipid-storage diseases. (c) 2017 International Parkinson and Movement Disorder Society
Databáze: OpenAIRE
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