Fig. 6

Anti-senescence and wound-healing effects of MSCs by TSC-derived secretome. The effect of TSC-CM or -EV on MSCs senescence was determined by SA-β-gal activity. A Representative images of SA-β-gal staining of TSC-EV-treated and untreated MSCs. Scale bars, 100 μm. SA-β -gal-positive cells in MSC-CM, TSC-CM, and -EV-treated MSCs cultured in GM B or SFM (C). D Relative expression levels of stemness-associated genes in MSCs treated with SFM, MSC-CM, TSC-CM, and -EV for 48 h. E Relative p53 mRNA levels in MSCs after 48 h incubation with SFM, MSC-CM, TSC-CM, and -EV. Error bars indicate the mean and SD. (n = 3; *p < 0.05, **p < 0.01, and ***p < 0.001) (F) Schematic illustration of experimental procedure for skin wound in mice (G) Relative wound region was calculated as actual wound area (red circle; S´) divided by initial wound area (yellow circle; S). H Representative photographs showing the wound-healing area in mice treated with SFM, MSC-CM, and TSC-CM-exposed MSCs on the skin wounds. Scale bars, 0.5 mm. I Quantitative analysis of wound closure percentage. J Representative images of human-specific lamin A/C staining with MSCs on wounded area in MSC-CM and TSC-CM treated groups. K The fluorescent intensity of lamin A/C was analyzed by imageJ. Histological analysis of the wound region using hematoxylin and eosin (H&E) (L, N) and Masson trichrome (MT) staining (M, O). Scale bars, 50 μm. P, Q Collagen expression (green) in the wound-healing area was determined by immunofluorescence staining. Scale bars, 20 μm. Data represent the mean ± SD of four to eight mice per group. (*p < 0.05 and **p < 0.01)