Mechanisms of GBA1 related PD in hiPSC derived neurons

Abstract

Parkinson's Disease (PD) is the second most common neurodegenerative disorder after Alzheimers Disease affecting approximately 5% of the population over 80 years of age. The exact mechanisms underlying the disease are not known but environmental as well as genetic factors have been described to contribute to the disease progression. Mutations in the gene GBA1 which encodes for the protein Glucoerebrosidase 1 (GCase) represent the most common genetic risk factor to develop PD and lead to reduced activity of the enzyme GCase. Importantly, considering the clinical representation, GBA1 related PD is similar to sporadic forms of the disease, making underlying mechanisms an interesting target to develop treatment strategies for PD. In the current work we investigate such underlying mechanisms using induced pluripotent stem cell (iPSC) derived neurons from PD patients with GBA1 mutations. We find that such neurons resemble PD associated features like loss of GCase activity, accumulation of alpha synuclein,disturbances in autophagy and calcium homeostasis as well as mitochondrial dysfunction. Finally, we show that application of the Nicotinamid adenosine dinucleotide (NAD) precursor Nicotinamid riboside (NR) partly rescues such defects in iPSC derived neurons as well as in vivo models of PD, making the NAD metabolism a promising target for the treatment of PD.