Abstract
Background: Combined effects of intrinsic and extrinsic ageing factors on skin tissue and the therapies have been rarely studied before. ADSCs have gained popularity in anti-ageing field, which may provide promising methods to fight against skin ageing. Objective: To find out the fate of HDFs exposed to intrinsic or extrinsic ageing factors or both of them and further examine the impacts of ADSC-CM on the damaged HDFs. Methods: We irradiated HDFs with UVB at different senescent levels, and then treated them with ADSC-CM. After 48 h, we detected cellular proliferative activity, morphology, SA-β-Gal expression, apoptosis, mRNA expression of collagen I, collagen III and elastin. Results: Intrinsic ageing factors inhibited cellular proliferation, increased senescent ratio and reduced mRNA expression of collagen I, collagen III and elastin, so did UVB, except for its induction of elastin mRNA expression. Furthermore, ADSC-CM treatment can slightly or significantly improve cellular proliferative activity and restore functions both in irradiated and non-irradiated HDFs. Besides, ADSC-CM treatment decreased cellular apoptosis and senescence induced by UVB but had no obvious effect on cellular senescence induced by intrinsic ageing factors. The results were similar in three generations of HDFs, yet in different degrees. Conclusions: The results suggest that ADSCs secretome protect HDFs from ageing damages but with some limitations.