Prion-Associated Neurodegeneration Causes Both Endoplasmic Reticulum Stress and Proteasome Impairment in a Murine Model of Spontaneous Disease

Prion diseases are a group of neurodegenerative disorders that can be spontaneous, familial or acquired by infection. The conversion of the prion protein PrP<sup>C</sup> to its abnormal and misfolded isoform PrP<sup>Sc</sup> is the main event in the pathogenesis of prion dise...

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Detalhes bibliográficos
Autores: Otero, Alicia, Betancor, Marina, Eraña, Hasier, Fernández-Borges, Natalia, Lucas, José Javier, Badiola Díez, Juan José, Castilla, Joaquín, Bolea, Rosa
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/227866
Acesso em linha:http://hdl.handle.net/10261/227866
Access Level:acceso abierto
Palavra-chave:ER Stress
Endoplasmatic reticulum
UPS impairment
Proteasome
Prions
Descrição
Resumo:Prion diseases are a group of neurodegenerative disorders that can be spontaneous, familial or acquired by infection. The conversion of the prion protein PrP<sup>C</sup> to its abnormal and misfolded isoform PrP<sup>Sc</sup> is the main event in the pathogenesis of prion diseases of all origins. In spontaneous prion diseases, the mechanisms that trigger the formation of PrP<sup>Sc</sup> in the central nervous system remain unknown. Several reports have demonstrated that the accumulation of PrP<sup>Sc</sup> can induce endoplasmic reticulum (ER) stress and proteasome impairment from the early stages of the prion disease. Both mechanisms lead to an increment of PrP aggregates in the secretory pathway, which could explain the pathogenesis of spontaneous prion diseases. Here, we investigate the role of ER stress and proteasome impairment during prion disorders in a murine model of spontaneous prion disease (TgVole) co-expressing the Ub<sup>G76V</sup>-GFP reporter, which allows measuring the proteasome activity in vivo. Spontaneously prion-affected mice showed a significantly higher accumulation of the PKR-like ER kinase (PERK), the ER chaperone binding immunoglobulin protein (BiP/Grp78), the ER protein disulfide isomerase (PDI) and the Ub<sup>G76V</sup>-GFP reporter than age-matched controls in certain brain areas. The upregulation of PERK, BiP, PDI and ubiquitin was detected from the preclinical stage of the disease, indicating that ER stress and proteasome impairment begin at early stages of the spontaneous disease. Strong correlations were found between the deposition of these markers and neuropathological markers of prion disease in both preclinical and clinical mice. Our results suggest that both ER stress and proteasome impairment occur during the pathogenesis of spontaneous prion diseases.