Aberrant Cell Cycle Gene Expression in a Transgenic Mouse Model of Alzheimer's Disease.

Alzheimer's disease (AD) is increasingly recognized as a disorder that extends beyond amyloid-β (Aβ) and tau pathology. To this end, growing evidence suggests that aberrant neuronal cell cycle re-entry (CCR) may contribute to neurodegeneration. To investigate this mechanism, we profiled the expression of 84 cell cycle-related genes in the brains of aged APP/PS1 mice, a widely used transgenic model of AD, and compared them with age-matched non-transgenic littermates. Our analysis revealed 32 differentially expressed genes (DEGs), 8 of which exhibited significant changes (fold change > 2, p < 0.05). Several of these DEGs, including CDC7 and CCNC, displayed consistent dysregulation in human AD brains as assessed using the AMP-AD knowledge portal, supporting their translational relevance. Furthermore, integration with miRNA prediction analyses identified candidate post-transcriptional regulators of these DEGs, highlighting novel layers of regulation. Collectively, our results provide the first systematic overview of cell cycle gene dysregulation in aged APP/PS1 mice, establish cross-species concordance with human AD, and propose miRNA-gene interactions as potential contributors to neuronal vulnerability. These findings underscore the importance of cell cycle pathways in AD pathogenesis and point to new avenues for therapeutic exploration.