Hsp110 mitigates α-synuclein pathology in vivo

Parkinson's disease is characterized by the aggregation of the presynaptic protein alpha-synuclein and its deposition into pathologic Lewy bodies. While extensive research has been carried out on mediators of alpha-synuclein aggregation, molecular facilitators of alpha-synuclein disaggregation are still generally unknown. We investigated the role of molecular chaperones in both preventing and disaggregating alpha-synuclein oligomers and fibrils, with a focus on the mammalian disaggregase complex. Here, we show that overexpression of the chaperone Hsp110 is sufficient to reduce alpha-synuclein aggregation in a mammalian cell culture model. Additionally, we demonstrate that Hsp110 effectively mitigates alpha-synuclein pathology in vivo through the characterization of transgenic Hsp110 and double-transgenic alpha-synuclein/Hsp110 mouse models. Unbiased analysis of the synaptic proteome of these mice revealed that overexpression of Hsp110 can override the protein changes driven by the alpha-synuclein transgene. Furthermore, overexpression of Hsp110 is sufficient to prevent endogenous alpha-synuclein templating and spread following injection of aggregated alpha-synuclein seeds into brain, supporting a role for Hsp110 in the prevention and/or disaggregation of alpha-synuclein pathology.