Comparative analysis of derived neurons from induced pluripotent stem cells (iPSC) to study the Gaucher disease and Parkinson\'s disease association

Author(s)

Fabiano Tófoli de Araujo

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB)
• Defense date: 2020-03-25

Examining board members

Lygia da Veiga Pereira Carramaschi; Merari de Fatima Ramires Ferrari; Gustavo José da Silva Pereira

• Advisor: Lygia da Veiga Pereira Carramaschi

Abstract

Parkinson\'s disease (PD) (PD - Parkinson Disease, MIM # 168600) is a neurodegenerative disease characterized by the death of dopaminergic neurons from substantia nigra pars compacta in the midbrain (mDAN). PD patients exhibit increased frequency of mutations in the GBA gene, which encodes the enzyme glucocerebrosidase (GCase) deficient in Gaucher Disease (GD), indicating a strong association between the two pathologies. Currently, the mechanism by which GBA mutations increase neuronal degeneration susceptibility is unknown. Knowledge of the molecular mechanisms of this association will contribute to a better understanding of the pathophysiological bases of neurodegeneration in PD, allowing the development of new therapeutic strategies. In the last years, our group has identified PD patients with mutations in GBA gene and collected blood samples from 3 different phenotypic groups: PD patients without a GBA gene mutation (PD), PD patients plus GBA gene mutation (PDGBA: 2 heterozygotes and 1 recessive homozygote presenting GD) and healthy controls (Ctrl). Here, we describe the use of hiPSCs derived from these patients to analyze the role of GBA in PD. The cell lineages were differentiated into dopaminergic neurons A9 of the midbrain (iDA), the main cell type affected by PD, in 3 culture conditions: normoxia, hypoxia and in normoxia under external magnetic field (EMF) stimulation. The production analysis of reactive oxygen species (ROS) revealed a decrease in ROS production and lysosomal activity in cells of PD patients with GBA mutation when compared to control cells and PD patients in hypoxia. The results of RNAseq analysis indicate that the gene signature for mature mDAN neurons was greater in the condition of hypoxia. Significant differences were also observed in the gene expression profile related to different metabolic pathways, revealing an exacerbated role of inflammatory responses in PD patients with GBA mutations. We propose that the deficiency of lysosomal activity caused by GBA creates a cycle of inflammation exacerbating this phenomenon already described in PD (AU)

• FAPESP's process: 14/24587-3 - Comparative analyses of induced pluripotent stem cell-derived neurons from patients with Gaucher disease and Parkinson
• Grantee: Fabiano Tófoli de Araújo
• Support Opportunities: Scholarships in Brazil - Doctorate