Exposure of Mesenchymal Stem Cells to an Alzheimer’s Disease Environment Enhances Therapeutic Effects

Abstract BackgroundMesenchymal stem cells (MSCs) have emerged as a promising tool for the treatment of Alzheimer’s disease (AD). Previous studies suggested that the co-culture of human MSCs with AD in an in vitro model reduced the expression of amyloid-beta 42 (Aβ42) in the medium as well as the overexpression of amyloid-beta (Aβ )-degrading enzymes such as neprilysin (NEP).MethodsIn this study, we focused on the role of primed MSCs (human Wharton's jelly-derived mesenchymal stem cells (WJ-MSCs) exposed to an AD cell line via a co-culture system) in reducing the levels of Aβ and inhibiting cell death. ResultsWe demonstrated that mouse groups treated with naïve MSCs and primed MSCs showed significant reductions in cell death, ubiquitin conjugate levels, and Aβ levels, but the effects were greater in primed MSCs. Also, mRNA sequencing data analysis indicated that high levels of TGF-β induced primed-MSCs. Furthermore, treatment with TGF-β reduced Aβ expression in an AD transgenic mouse model. ConclusionAD environmental preconditioning is a promising strategy to reduce cell death and ubiquitin conjugate levels and maintain the stemness of MSCs. Further, these data suggest that human WJ-MSCs exposed to an AD environment may represent a promising and novel therapy for AD.