A laboratory study indicates that the main protein involved in Parkinson’s disease pathology does not behave as a prion when overexpressed.
In Parkinson’s disease, the protein alpha-synuclein aggregates within neurons of patients and appears to propagate across interconnected areas of the brain. How this happens remains largely unknown. It has been proposed that alpha-synuclein may behave like a prion: pathological forms of the protein may be capable of changing the conformation of normal alpha-synuclein and thus triggering its aggregation and neuron-to-neuron propagation (a phenomenon referred to as “seeding”). Recent findings by scientists reveal that aggregation, spreading and pathology caused by alpha-synuclein do not necessarily involve prion-like seeding. Instead, they could be triggered by enhanced alpha-synuclein expression and trans-neuronal passage of monomeric and oligomeric forms of the protein.
“We believe that these findings bear a number of important implications for disease pathogenesis. Not only can we conclude that long-distance diffusion of alpha-synuclein does not necessarily require the generation of prion-like species," said researcher Donato Di Monte. "Our data also reveal that spreading and pathology can be triggered by simple overexpression of the protein and are mediated, at least initially, by monomeric and/or oligomeric alpha-synuclein.”
Researchers report on this in the journal Brain.