Periodic Reporting for period 1 - MitSyn (Alpha-synuclein and mitochondrial dysfunction: key links between Gaucher’s disease and Parkinson’s?)
Période du rapport: 2015-04-13 au 2017-04-12
The Mitsyn project allowed to further characterize the interplay between lysosomes and mitochondria, which seems to be crucial in the aethiopathogenesis of several neurodegenerative disorders.
Moreover, we started unraveling the signaling mechanisms responsible for autophagy impairment upstream of lysosomes in gba-/- neurons, brains and mouse embryonic fibroblasts, using lipidomics approaches and studying Akt/mTOR signaling pathways.
We have also generated human iPSC lines from fibroblasts from patients with PD carrying the fascinating E326K mutation of GBA, which is linked to PD but not to GD even when homozygous, and we obtained iPSC lines derived from PD patients carrying the L444P and the N370S GBA mutations to have a more complete picture of GBA-associated PD. After the iPSC characterization, they were differentiated to dopaminergic neurons adapting a protocol published in Nature by Kriks et al. (2011). Neurons were characterized in term of neuronal and dopaminergic markers expression and in term of glutamate and high potassium response, measured as variation in cytosolic calcium.
Preliminary experiments on mitochondrial function in iPSC-derived dopaminergic neurons after their characterization were done: mitochondrial membrane potential, free radical production and cytosolic calcium levels upon high potassium stimulation were measured. Given the high variability in these cultures, more replicates will be needed to draw any conclusion.
The results obtained so far were presented at different international conferences (EBEC 2016 and GRC Lysosomal Diseases 2017) and at local/international seminars. At least two publications will be soon published summarizing the results obtained during the Mitsyn project.
A review on the mitochondrial dysfunction in lysosomal diseases was also published (Plotegher N, Duchen MR. Mitochondrial Dysfunction and Neurodegeneration in Lysosomal Storage Disorders. Trends Mol Med. 2017).