Lewy Body-like Inclusions in Human Midbrain Organoids Carrying Glucocerebrosidase and α-Synuclein Mutations

Ann Neurol. 2021 Sep;90(3):490-505. doi: 10.1002/ana.26166. Epub 2021 Aug 10.

Abstract

Objective: We utilized human midbrain-like organoids (hMLOs) generated from human pluripotent stem cells carrying glucocerebrosidase gene (GBA1) and α-synuclein (α-syn; SNCA) perturbations to investigate genotype-to-phenotype relationships in Parkinson disease, with the particular aim of recapitulating α-syn- and Lewy body-related pathologies and the process of neurodegeneration in the hMLO model.

Methods: We generated and characterized hMLOs from GBA1-/- and SNCA overexpressing isogenic embryonic stem cells and also generated Lewy body-like inclusions in GBA1/SNCA dual perturbation hMLOs and conduritol-b-epoxide-treated SNCA triplication hMLOs.

Results: We identified for the first time that the loss of glucocerebrosidase, coupled with wild-type α-syn overexpression, results in a substantial accumulation of detergent-resistant, β-sheet-rich α-syn aggregates and Lewy body-like inclusions in hMLOs. These Lewy body-like inclusions exhibit a spherically symmetric morphology with an eosinophilic core, containing α-syn with ubiquitin, and can also be formed in Parkinson disease patient-derived hMLOs. We also demonstrate that impaired glucocerebrosidase function promotes the formation of Lewy body-like inclusions in hMLOs derived from patients carrying the SNCA triplication.

Interpretation: Taken together, the data indicate that our hMLOs harboring 2 major risk factors (glucocerebrosidase deficiency and wild-type α-syn overproduction) of Parkinson disease provide a tractable model to further elucidate the underlying mechanisms for progressive Lewy body formation. ANN NEUROL 2021;90:490-505.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Embryonic Stem Cells / metabolism
  • Glucosylceramidase / deficiency*
  • Glucosylceramidase / genetics
  • Humans
  • Lewy Bodies / genetics
  • Lewy Bodies / metabolism*
  • Lewy Bodies / pathology
  • Mesencephalon / metabolism*
  • Mesencephalon / pathology
  • Mutation / physiology*
  • Organoids / metabolism*
  • Organoids / pathology
  • alpha-Synuclein / biosynthesis*
  • alpha-Synuclein / genetics

Substances

  • SNCA protein, human
  • alpha-Synuclein
  • GBA protein, human
  • Glucosylceramidase