The thesis used an in vivo model to evaluate the efficacy of the total protein of sika deer antler and its component DAP4 in improving AD, which may be involved in the interaction between the “microbe–gut–brain” axis through the tyrosine metabolism pathway, activate the PI3K/Akt/Nrf2 signaling pathway, and improve the effect of AD. This evidence concerns the gene AKT1 and Alzheimer disease.