Resumen
Olfactory dysfunction is among the earliest features of Alzheimer’s disease (AD). Although neuropathological abnormalities have been detected in the olfactory bulb (OB), little is known about its dynamic biology. Here, OB- proteome analysis showed a stage-dependent synaptic proteostasis impairment during AD evolution. In addition to progressive modulation of tau and amyloid precursor protein (APP ...
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Olfactory dysfunction is among the earliest features of Alzheimer’s disease (AD). Although neuropathological abnormalities have been detected in the olfactory bulb (OB), little is known about its dynamic biology. Here, OB- proteome analysis showed a stage-dependent synaptic proteostasis impairment during AD evolution. In addition to progressive modulation of tau and amyloid precursor protein (APP) interactomes, network-driven proteomics revealed an early disruption of upstream and downstream p38 MAPK pathway and a subsequent impairment of Phosphoinositide-dependent protein kinase 1 (PDK1)/Protein kinase C (PKC) signaling axis in the OB from AD subjects. Moreover, a mitochondrial imbalance was evidenced by a depletion of Prohibitin-2 (Phb2) levels and a specific decrease in the phosphorylated isoforms of Phb1 in intermediate and advanced AD stages. Interestingly, olfactory Phb subunits were also deregulated across different types of dementia. Phb2 showed a specific up-regulation in mixed dementia, while Phb1 isoforms were down-regulated in frontotemporal lobar degeneration (FTLD). However, no differences were observed in the olfactory expression of Phb subunits in progressive supranuclear palsy (PSP). To sum up, our data reflect, in part, the missing links in the biochemical understanding of olfactory dysfunction in AD, unveiling Phb complex as a differential driver of neurodegeneration at olfactory level. [--]
Publicado en
Scientific Reports, 7: 9115
Departamento
Universidad Pública de Navarra. Departamento de Ciencias de la Salud /
Nafarroako Unibertsitate Publikoa. Osasun Zientziak Saila
Entidades Financiadoras
This work was funded by grants from the Spanish Ministry of Economy and Competitiveness (MINECO) (Ref. SAF2014-59340-R), Department of Economic Development from Government of Navarra (Ref. PC025), and Obra Social la Caixa to ES. AGM and KA are supported by PEJ-2014-A-61949 and PEJ-2014-A-72151 (MINECO). EPV is supported by PTA-2013/8711/I (MINECO). MLM is supported by a predoctoral fellowship from the Public University of Navarra (UPNA). The Proteomics Unit of Navarrabiomed is a member of Proteored, PRB2-ISCIII, and is supported by grant PT13/0001, of the PE I + D + I 2013-2016 funded by ISCIII and FEDER.