APP and Alzheimer disease: Consistently, the results of this study showed that APP/PS1 mice had severe Aβ deposition in the brain, a loss of dendritic spines, and impaired spatial learning and memory, suggesting that the AD-model mice successfully developed AD-like lesions, while aerobic exercise reversed the above changes; inhibited Aβ deposition, brain cell apoptosis, and dendritic spine loss; and alleviated the spatial learning and memory impairment in APP/PS1 mice.