Large-scale proteomics analysis of five brain regions from Parkinson's disease patients with a GBA1 mutation.

Despite being the second most common neurodegenerative disorder, little is known about Parkinson's disease (PD) pathogenesis. A number of genetic factors predispose towards PD, among them mutations in GBA1, which encodes the lysosomal enzyme acid-β-glucosidase. We now perform non-targeted, mass spectrometry based quantitative proteomics on five brain regions from PD patients with a GBA1 mutation (PD-GBA) and compare to age- and sex-matched idiopathic PD patients (IPD) and controls. Two proteins were differentially-expressed in all five brain regions whereas significant differences were detected between the brain regions, with changes consistent with loss of dopaminergic signaling in the substantia nigra, and activation of a number of pathways in the cingulate gyrus, including ceramide synthesis. Mitochondrial oxidative phosphorylation was inactivated in PD samples in most brain regions and to a larger extent in PD-GBA. This study provides a comprehensive large-scale proteomics dataset for the study of PD-GBA.