On this basis, the study of Circulation Research in 2023 further clarified the specific molecular mechanism: the exosomes secreted by AD-MSCs are rich in miR-125a, which can inhibit the activation of the TLR4/NF-κB pathway by targeting TLR4 mRNA in macrophages, reduce the release of IL-1β and MCP-1, and thus inhibit the recruitment of monocytes and the formation of foam cells. This evidence concerns the gene TLR4 and Alzheimer disease.