Abstract
Alzheimer's disease (AD) is a neurodegenerative condition characterized by progressive memory loss and other cognitive disturbances. Patients with AD can be vulnerable to vascular damage, and damaged vessels can lead to cognitive impairment. Mesenchymal stem cell (MSC) treatment has shown potential in ameliorating AD pathogenesis, but its effect on vascular function remains unclear. This study aimed to improve cognitive function by alleviating atherosclerosis-induced vessel damage using MSCs in mice with a genetic AD background. In this study, a 5xFAD mouse model of AD was used, and atherosclerotic vessel damage was induced by high-fat diets (HFDs). MSCs were injected into the tail vein along with mannitol in 5xFAD mice on an HFD. MSCs were detected in the brain, and vascular damage was improved following MSC treatment. Behavioral tests showed that MSCs enhanced cognitive function, as measured by the Y-maze and passive avoidance tests. Additionally, muscle strength measured by the rotarod test was also increased by MSCs in AD mice with vessel damage induced by HFDs. Overall, our results suggest that stem cells can alleviate vascular damage caused by metabolic diseases, including HFDs, and vascular disease in individuals carrying the AD gene. Consequently, this alleviates cognitive decline related to vascular dementia symptoms.