Last Updated: 2026-03-29 PT
This knowledge gap addresses one of the central unresolved questions in Parkinson's disease (PD) pathogenesis: how does alpha-synuclein (α-syn) pathology spread through the nervous system in a prion-like manner, and what determines which α-syn conformations (strains) are pathogenic versus benign? Understanding the mechanisms of cell-to-cell transmission, templated recruitment, and strain diversity is critical for developing disease-modifying therapies that can halt disease progression. [1]
The prion-like hypothesis proposes that misfolded α-syn can template the misfolding of endogenous protein, propagating pathology from affected neurons to connected regions. This mechanism may explain the characteristic spread of Lewy pathology from the brainstem to cortical regions observed in Braak staging, correlating with progressive clinical symptoms. If α-syn spreading is a primary driver of disease progression, therapies targeting transmission could potentially halt neurodegeneration at any disease stage. [2]
Alpha-synuclein can transfer between neurons through multiple mechanisms: [3]
Not all α-syn conformations are equally capable of templated recruitment: [4]
The process of seeded aggregation involves: [5]
| Gap | Description | Research Priority |
|---|---|---|
| Transmission routes | What are the primary physiological pathways for α-syn spread in vivo? | High |
| Strain classification | Can we define distinct α-syn strains and correlate with clinical subtypes? | High |
| Initiation triggers | What initiates first misfolding in sporadic PD? | Critical |
| Barrier mechanisms | Why are some neuronal populations resistant to α-syn pathology? | Medium |
| Therapeutic targets | Can we block cell-to-cell transmission without disrupting normal synaptic function? | Critical |
Recent findings (March 2026) on alpha-synuclein spreading mechanisms:
Braak et al. Staging of brain pathology related to sporadic Parkinson's disease (2003). 2003. ↩︎
Goedert et al. The propagation of alpha-synuclein pathology in Parkinson's disease (2020). 2020. ↩︎
Jucker et al. The spread and strains of alpha-synuclein pathology (2013). 2013. ↩︎
Surmeier et al. Calcium and alpha-synuclein in sporadic Parkinson's disease (2017). 2017. ↩︎
Kalia et al. Parkinson's disease (2015). 2015. ↩︎
TMEM16F regulates pathologic alpha-synuclein secretion and spread (2024). 2024. ↩︎
Phospho-Ser129 alpha-synuclein in Lewy body disease (2024). 2024. ↩︎
Strain-specific antibody binding to Lewy body pathology (2024). 2024. ↩︎
Activity-dependent alpha-synuclein transmission (2024). 2024. ↩︎