Resumen: The self-assembly of a-synuclein (aS) into intraneuronal inclusion bodies is a key characteristic of Parkinson’s disease. To define the nature of the species giving rise to neuronal damage, we have investigated the mechanism of action of the main aS populations that have been observed to form progressively during fibril growth. The aS fibrils release soluble prefibrillar oligomeric species with cross-ß structure and solvent-exposed hydrophobic clusters. aS prefibrillar oligomers are efficient in crossing and permeabilize neuronal membranes, causing cellular insults. Short fibrils are more neurotoxic than long fibrils due to the higher proportion of fibrillar ends, resulting in a rapid release of oligomers. The kinetics of released aS oligomers match the observed kinetics of toxicity in cellular systems. In addition to previous evidence that aS fibrils can spread in different brain areas, our in vitro results reveal that aS fibrils can also release oligomeric species responsible for an immediate dysfunction of the neurons in the vicinity of these species. Idioma: Inglés DOI: 10.1038/s41467-021-21937-3 Año: 2021 Publicado en: Nature communications 12, 1 (2021), 1814 [16 pp] ISSN: 2041-1723 Factor impacto JCR: 17.694 (2021) Categ. JCR: MULTIDISCIPLINARY SCIENCES rank: 6 / 74 = 0.081 (2021) - Q1 - T1 Factor impacto CITESCORE: 23.2 - Biochemistry, Genetics and Molecular Biology (Q1) - Physics and Astronomy (Q1)