Since the accumulation of α-synuclein has been considered critical to the pathogenesis of PD among several possible pathways through which glucocerebrosidase (GCase) deficiency may promote the pathogenesis of PD, particular attention was given to the reciprocity with α-synuclein levels, lysosomal dysfunction, endoplasmatic reticulum-Golgi trafficking of GCase, dysregulation of calcium homeostasis and mitochondrial abnormalities.
The potential cytotoxicity of accumulated amyloid β protein (Aβ42) and its oligomers, phosphorylated tau in the form of paired helical filaments and α-synuclein, and the putative pathogenic role and cause of the mitochondrial abnormalities and oxidative stress are reviewed.
The muscle-fiber molecular phenotype exhibits similarities to both Alzheimer-disease (AD) and Parkinson-disease (PD) brains, including accumulations of amyloid-beta, phosphorylated tau, alpha-synuclein, and parkin, as well as evidence of oxidative stress and mitochondrial abnormalities.