title: Aggregated α-synuclein and complex I deficiency: exploration of their relationship in differentiated neurons.
abstract: α-Synuclein becomes misfolded and aggregated upon damage by various factors, for example, by reactive oxygen species. These aggregated forms have been proposed to have differential toxicities and their interaction with mitochondria may cause dysfunction within this organelle that contributes to the pathogenesis of Parkinson's disease (PD). In particular, the association of α-synuclein with mitochondria occurs through interaction with mitochondrial complex I and importantly defects of this protein have been linked to the pathogenesis of PD. Therefore, we investigated the relationship between aggregated α-synuclein and mitochondrial dysfunction, and the consequences of this interaction on cell survival. To do this, we studied the effects of α-synuclein on cybrid cell lines harbouring mutations in either mitochondrial complex I or IV. We found that aggregated α-synuclein inhibited mitochondrial complex I in control and complex IV-deficient cells. However, when aggregated α-synuclein was applied to complex I-deficient cells, there was no additional inhibition of mitochondrial function or increase in cell death. This would suggest that as complex I-deficient cells have already adapted to their mitochondrial defect, the subsequent toxic effects of α-synuclein are reduced.
authors.affiliation: Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: A K
authors.initials: AK
authors.lastname: Reeve
authors.affiliation: Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK.
authors.forename: M H R
authors.initials: MH
authors.lastname: Ludtmann
authors.affiliation: Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK.
authors.forename: P R
authors.initials: PR
authors.lastname: Angelova
authors.affiliation: Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: E M
authors.initials: EM
authors.lastname: Simcox
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK.
authors.forename: M H
authors.initials: MH
authors.lastname: Horrocks
authors.affiliation: Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, UK.
authors.forename: D
authors.initials: D
authors.lastname: Klenerman
authors.affiliation: Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK.
authors.forename: S
authors.initials: S
authors.lastname: Gandhi
authors.affiliation: Wellcome Trust Centre for Mitochondrial Research, Institute for Neuroscience, Newcastle University Institute for Ageing, Newcastle University, Newcastle upon Tyne, UK.
authors.forename: D M
authors.initials: DM
authors.lastname: Turnbull
authors.affiliation: Department of Molecular Neuroscience, Institute of Neurology, University College London, London, UK.
authors.forename: A Y
authors.initials: AY
authors.lastname: Abramov
mesh_terms: D000818:Animals; D042967:Electron Transport Complex I / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D006801:Humans; D053078:Membrane Potential, Mitochondrial; D051379:Mice; D008928:Mitochondria / Q000378:metabolism / Q000473:pathology; D028361:Mitochondrial Diseases / Q000235:genetics / Q000473:pathology; D009154:Mutation; D009474:Neurons / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress / Q000235:genetics*; D010300:Parkinson Disease / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D066263:Protein Aggregation, Pathological / Q000235:genetics; D017382:Reactive Oxygen Species / Q000378:metabolism; D051844:alpha-Synuclein / Q000235:genetics* / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D051844:alpha-Synuclein; D042967:Electron Transport Complex I