The HSP70 molecular chaperone is not beneficial in a mouse model of α-synucleinopathy

Background Aggregation and misfolded α-synuclein is thought to be central in the pathogenesis of Parkinson`s disease (PD). Heat-shock proteins (HSPs) that are involved in refolding and degradation processes could lower the aggregate load of α-synuclein and thus be beneficial in α-synucleinopathies. Methodology/Principal Findings We co-overexpressed human A53T point-mutated α-synuclein and human HSP70 in mice, both under the control of Thy1 regulatory sequences. Behavior read-outs showed no beneficial effect of HSP70 expression in mice. In contrast, motor coordination, grip strength and weight were even worse in the α-synucleinopathy model in the presence of HSP70 overexpression. Biochemical analyses revealed no differences in α-synuclein oligomers/aggregates, truncations and phosphorylation levels and α-synuclein localization was unchanged in immunostainings. Conclusion/Significance Overexpressing HSP70 in a mouse model of α-synucleinopathy did not lower the toxic load of α-synuclein species and had no benefical effect on α-synuclein-related motor deficits