Pathological features and molecular signatures of early olfactory dysfunction in 3xTg-AD model mice.
CNS Neurosci Ther
; 30(2): e14632, 2024 02.
Article
en En
| MEDLINE
| ID: mdl-38366763
ABSTRACT
BACKGROUND:
Olfactory dysfunction is known to be an early manifestation of Alzheimer's disease (AD). However, the underlying mechanism, particularly the specific molecular events that occur during the early stages of olfactory disorders, remains unclear.METHODS:
In this study, we utilized transcriptomic sequencing, bioinformatics analysis, and biochemical detection to investigate the specific pathological and molecular characteristics of the olfactory bulb (OB) in 4-month-old male triple transgenic 3xTg-AD mice (PS1M146V/APPSwe/TauP301L).RESULTS:
Initially, during the early stages of olfactory impairment, no significant learning and memory deficits were observed. Correspondingly, we observed significant accumulation of amyloid-beta (Aß) and Tau pathology specifically in the OB, but not in the hippocampus. In addition, significant axonal morphological defects were detected in the olfactory bulb, cortex, and hippocampal brain regions of 3xTg-AD mice. Transcriptomic analysis revealed a significant increase in the expression of neuroinflammation-related genes, accompanied by a significant decrease in neuronal activity-related genes in the OB. Moreover, immunofluorescence and immunoblotting demonstrated an activation of glial cell biomarkers Iba1 and GFAP, along with a reduction in the expression levels of neuronal activity-related molecules Nr4a2 and FosB, as well as olfaction-related marker OMP.CONCLUSION:
In sum, the early accumulation of Aß and Tau pathology induces neuroinflammation, which subsequently leads to a decrease in neuronal activity within the OB, causing axonal transport deficits that contribute to olfactory disorders. Nr4a2 and FosB appear to be promising targets for intervention aimed at improving early olfactory impairment in AD.Palabras clave
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Enfermedad de Alzheimer
/
Trastornos del Olfato
Límite:
Animals
Idioma:
En
Revista:
CNS Neurosci Ther
Asunto de la revista:
NEUROLOGIA
/
TERAPEUTICA
Año:
2024
Tipo del documento:
Article