Efficacy and safety of umbilical cord-derived mesenchymal stem cell-conditioned media for preventing and treating skin aging

Figure 4 In vivo effectiveness test of umbilical cord-derived mesenchymal stem cell-conditioned medium. A: Representative histological images of aged mouse skin stained with hematoxylin-eosin, Ki-67, and Masson’s Trichrome stains. Scale bar = 50 μm; B-E: Quantitative analysis of epidermal thickness (B), dermal thickness (C), number of Ki-67-positive cells per unit area (D), and collagen deposition area (E) according to the type of reagent; F-I: Quantitative analysis of epidermal thickness (F), dermal thickness (G) number of Ki-67-positive cells per unit area (H), and collagen deposition area (I) according to the method used for umbilical cord-derived mesenchymal stem cell-conditioned medium administration; J: Serial sections of aged mouse skin stained with Ki-67 and β-galactosidase. Scale bar = 20 μm; K: Quantification of β-galactosidase expression per epidermal cell. All quantitative data (B-I and K) were obtained from color-based image analysis of stained tissue sections. NS: Not significant; AD-AP: Adipose-derived mesenchymal stem cell-conditioned medium application; UC-AP: Umbilical cord-derived mesenchymal stem cell-conditioned medium application; UC-SC: Umbilical cord-derived mesenchymal stem cell-conditioned medium subcutaneous injection; UC-IV: Umbilical cord-derived mesenchymal stem cell-conditioned medium tail-vein injection; ADMSC-CM: Adipose-derived mesenchymal stem cell-conditioned medium; UCMSC-CM: Umbilical cord-derived mesenchymal stem cell-conditioned medium.