International Journal of Molecular Sciences (Jul 2022)

Neuronal ApoE Regulates the Cell-to-Cell Transmission of α-Synuclein

  • Seo-Jun Kang,
  • Soo-Jeong Kim,
  • Hye Rin Noh,
  • Beom Jin Kim,
  • Jae-Bong Kim,
  • Uram Jin,
  • Sun Ah Park,
  • Sang Myun Park

DOI
https://doi.org/10.3390/ijms23158311
Journal volume & issue
Vol. 23, no. 15
p. 8311

Abstract

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The presence of protein inclusions, called Lewy bodies (LBs) and Lewy neurites (LNs), in the brain is the main feature of Parkinson’s disease (PD). Recent evidence that the prion-like propagation of α-synuclein (α-syn), as a major component of LBs and LNs, plays an important role in the progression of PD has gained much attention, although the molecular mechanism remains unclear. In this study, we evaluated whether neuronal ApoE regulates the cell-to-cell transmission of α-syn and explored its molecular mechanism using in vitro and in vivo model systems. We demonstrate that neuronal ApoE deficiency attenuates both α-syn uptake and release by downregulating LRP-1 and LDLR expression and enhancing chaperone-mediated autophagy activity, respectively, thereby contributing to α-syn propagation. In addition, we observed that α-syn propagation was attenuated in ApoE knockout mice injected with pre-formed mouse α-syn fibrils. This study will help our understanding of the molecular mechanisms underlying α-syn propagation.

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