Extracellular matrix modulating effects of amnion-derived mesenchymal stem cells on aging skin wounds in α-Klotho knockout mice.

Aim: Wounds in the elderly are frequently recalcitrant and chronic as a result of the effects of skin aging and associated complications. The objective of this study is to utilize an α-Klotho knockout (KO) mice wound model to assess the capacity of amnion-derived mesenchymal stem cells (AMSCs) to facilitate wound healing in aging skin.

Methods: AMSCs were applied topically to the wound after extraction and gelatinization of the conditioned medium (CM). Animal experiments were performed with two distinct mouse strains: α-Klotho KO mice and wild-type mice. Full-thickness skin defect models with a diameter of 8 mm were created by incising the skin on the left and right sides of the dorsum. On day 8 after wound creation, the mice were sacrificed, and wound tissue was collected for analysis through histological and immunohistochemical evaluations, as well as through quantitative polymerase chain reaction.

Results: The topical application of CM gel to wounds of α-Klotho KO mice demonstrated that wound healing was significantly higher than that observed in control, reaching the wound closure rate of wild-type mice on day 8. Additionally, gene expression analysis of wound tissue indicated that AMSC-CM may regulate extracellular matrix formation and fibrosis. Moreover, histological analysis indicated that AMSC-CM may facilitate wound contraction of aging skin wounds of α-Klotho KO mice by inducing myofibroblast differentiation and promoting granulation and collagen formation, which are the primary components of the extracellular matrix.

Conclusions: AMSC-CM may facilitate wound healing in aging skin of α-Klotho KO mice by regulating the extracellular matrix. Geriatr Gerontol Int 2025; 25: 701-708.