To assess the effects of BM-MSC-EVs in the APP/PS1 AD mice at early stages of the disease, before the behavioral manifestations become apparent, we performed intraparenchymal injections of EVs in the cortex of mice at 3 and 5 months of age and evaluated, 25 days later, EV effects on two of the typical early signs of the disease, Aβ deposition and appearance of dystrophic neurites (Figure 3 and Figure 4). Here, APP is linked to Alzheimer disease.