Glial α-synuclein promotes neurodegeneration characterized by a distinct transcriptional program in vivo

Glia. 2019 Oct;67(10):1933-1957. doi: 10.1002/glia.23671. Epub 2019 Jul 3.

Abstract

α-Synucleinopathies are neurodegenerative diseases that are characterized pathologically by α-synuclein inclusions in neurons and glia. The pathologic contribution of glial α-synuclein in these diseases is not well understood. Glial α-synuclein may be of particular importance in multiple system atrophy (MSA), which is defined pathologically by glial cytoplasmic α-synuclein inclusions. We have previously described Drosophila models of neuronal α-synucleinopathy, which recapitulate key features of the human disorders. We have now expanded our model to express human α-synuclein in glia. We demonstrate that expression of α-synuclein in glia alone results in α-synuclein aggregation, death of dopaminergic neurons, impaired locomotor function, and autonomic dysfunction. Furthermore, co-expression of α-synuclein in both neurons and glia worsens these phenotypes as compared to expression of α-synuclein in neurons alone. We identify unique transcriptomic signatures induced by glial as opposed to neuronal α-synuclein. These results suggest that glial α-synuclein may contribute to the burden of pathology in the α-synucleinopathies through a cell type-specific transcriptional program. This new Drosophila model system enables further mechanistic studies dissecting the contribution of glial and neuronal α-synuclein in vivo, potentially shedding light on mechanisms of disease that are especially relevant in MSA but also the α-synucleinopathies more broadly.

Keywords: Drosophila; Parkinson's disease; glia; multiple system atrophy; α-Synuclein.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Cell Death / physiology
  • Constipation / metabolism
  • Disease Models, Animal
  • Dopaminergic Neurons / metabolism
  • Dopaminergic Neurons / pathology
  • Drosophila
  • Humans
  • Movement Disorders / metabolism
  • Movement Disorders / pathology
  • Nerve Degeneration / metabolism*
  • Nerve Degeneration / pathology
  • Neurodegenerative Diseases / metabolism*
  • Neurodegenerative Diseases / pathology
  • Neuroglia / metabolism*
  • Neuroglia / pathology
  • Protein Aggregation, Pathological / metabolism
  • Protein Aggregation, Pathological / pathology
  • Transcription, Genetic
  • Transcriptome*
  • alpha-Synuclein / metabolism*

Substances

  • SNCA protein, human
  • alpha-Synuclein