Synergistic Effect of Adipose-Derived Stem Cells and Fat Graft on Wrinkles in Aged Mice

Background: The authors investigated the synergistic effects of adipose-derived stem cells and fat graft on skin wrinkles in a nude mouse model of chronologic aging. Methods: After 50 weeks of chronologic aging, 44 female BALB/c nude mice were classified into four groups: (1) negative control, (2) mice injected subcutaneously with fat on the back skin (0.5 cm(3)), (3) mice injected with adipose-derived stem cells (1 x 10(5) cells in 0.5 cm(3) Hanks balanced salt solution), and (4) mice injected with both fat (0.5 cm(3)) and adipose-derived stem cells (1 x 10(5) cells in 0.5 cm(3) Hanks balanced salt solution). The degree of wrinkling was evaluated using replica analysis, and skin biopsies were performed after 4 weeks. The dermal thickness and density of collagen were determined. Type I procollagen and matrix metalloproteinase levels were determined using real-time polymerase chain reaction and Western blot analysis. Tropoelastin, fibrillin-1, and CD31 levels were evaluated using immunohistochemistry. Results: Based on the total wrinkle area, there was significant wrinkle reduction in the fat-treated and adipose-derived stem cell with fat-treated groups. Type I procollagen mRNA and collagen levels were significantly higher in the adipose-derived stem cell with fat-treated group than in the adipose-derived stem cell-treated and the fat-treated groups. In addition, the adipose-derived stem cells with fat graft group exhibited significantly higher CD31 expression level than the adipose-derived stem cell-treated and the fat-treated groups. Conclusion: Both adipose-derived stem cells and fat graft have a wrinkle-reducing effect and synergistically affect collagen synthesis and neovascularization.