Abstract title: Efficacy of alpha-syn aggregate disassembling compounds in primary cortical neurons
Poster board: SHIFT 02-130
Poster number: 3034
Authors: Linnea Strid Orrhult1, Marc Sevenich2, Albin Skilje1, Johan Pihl1, and Antje Willuweit2
Affiliations: 1Cellectricon AB, Mölndal, Sweden, 2Priavoid GmbH, Düsseldorf, Germany
Aims: Neurodegenerative diseases like Parkinson’s disease (PD) are triggered by harmful aggregation of proteins such as the physiological monomer alpha-synuclein (αSyn). αSyn oligomers continue to grow into insoluble fibrils/aggregates that impair multiple cellular functions, eventually leading to neuronal death. In the current study, the aim was to test therapeutic all-D peptides and evaluate their modulation of αSyn aggregation using an in vitro model. The compounds tested here were designed to bind and stabilize the physiological αSyn monomer unit, which results in disassembly of aggregates like fibrils and oligomers.
Methods: An established αSyn aggregation assay for target discovery and validation was used, with adjustments to evaluate compound effects. In short, therapeutic compounds were added in a concentration-response format into the medium of primary mouse embryonic (E18) cortical neurons at 7 days in vitro (DIV). One day later, αSyn aggregation was induced by addition of pre-formed fibrils (PFFs) at 8 DIV upon medium exchange. Using an unbiased automated image analysis workflow, the effect of the compounds on αSyn aggregation (assessed by phosphorylation of Ser129) and cell health was evaluated two weeks after PFF addition.
Results: None of the compounds affected cell health, i.e. the total cell number and number of neuronal cells. A decrease in PFF induced αSyn aggregation was observed with effective concentrations in the nM range even after single administration to the cell medium. Indications of the specificity of the compound effect were determined by a multivariate analysis using principal component analysis.
Conclusions: The compounds developed for disassembly of αSyn aggregates are effective in nM concentration range in primary neurons, which is consistent with their high efficacy in disassembling synthetic αSyn aggregates.