Protective exercise responses in the dentate gyrus of Alzheimer's disease mouse model revealed with single-nucleus...

Exercise's protective effects in Alzheimer's disease (AD) are well recognized, but cell-specific contributions to this phenomenon remain unclear. Here we used single-nucleus RNA sequencing (snRNA-seq) to dissect the response to exercise (free-wheel running) in the neurogenic stem-cell niche of the hippocampal dentate gyrus in male APP/PS1 transgenic AD model mice. Transcriptomic responses to exercise were distinct between wild-type and AD mice, and most prominent in immature neurons. Exercise restored the transcriptional profiles of a proportion of AD-dysregulated genes in a cell type-specific manner. We identified a neurovascular-associated astrocyte subpopulation, the abundance of which was reduced in AD, whereas its gene expression signature was induced with exercise. Exercise also enhanced the gene expression profile of disease-associated microglia. Oligodendrocyte progenitor cells were the cell type with the highest proportion of dysregulated genes recovered by exercise. Last, we validated our key findings in a human AD snRNA-seq dataset. Together, these data present a comprehensive resource for understanding the molecular mediators of neuroprotection by exercise in AD.