Determination of adipose-derived stem cell application on photo-aged fibroblasts, based on paracrine function

Background aims. Adipose-derived stem cells (ASC) are known to be able to restore injured tissue via differentiation and paracrine effects. In this study, we investigated the effect of ASC on photo-aged human dermal fibroblasts (HDF) based on paracrine function. In particular, we wanted to determine a more effective method of ASC application and the fate of the photo-aged fibroblasts. Methods. We compared two application methods of ASC: transwell and conditioned medium culture with photo-aged fibroblasts. Proliferation rate, collagen synthesis, matrix metalloproteinase (MMP) production and expression of p16 were measured by real-time polymerase chain reaction (PCR) after culture. Flow cytometry for apoptosis assay was also conducted to determine the fate of the photo-aged fibroblasts. Results. ASC induced proliferation of photo-aged HDF and type I collagen production and decreased MMP-1 production and expression of p16. In an apoptosis assay, ASC converted necrotic or late apoptotic cells to early apoptotic cells. These results were similar in both experimental groups. Conclusions. The results indicate that the paracrine effects of ASC may have a role that is as important as cell-to-cell communication between ASC and fibroblasts. We believe that conditioned medium may be a useful material for anti-aging skin therapy instead of cell therapy. Also, ASC might have an anti-aging effect on photo-aged fibroblasts even at a genetic level.