Autophagy in human skin fibroblast model for photoaging

Objective To observe the changes of autophagy in human skin fibroblast (HSF) model for photoaging. Methods HSF model for photoaging was established through repeated exposure to ultraviolet B (UVB). Those HSFs receiving no irradiation served as the control. The degree of aging was evaluated by p-galactosidase assay, and autophagy level was detected. Results After repeated exposure to UVB, most pho-toaged HSFs were deformed and distorted, and some of them even died. The percentage of P-galactosidase-positive cells was 50.60% ± 5.04% and 14.58% ± 2.69%, respectively in photoaged and control HSFs (P< 0.01). Significant difference was also observed in the proportion of cytophagosome-positive cells between photoaged and control HSFs (14.91% ± 4.59% vs 68.45% ± 8.25%, P < 0.01). Conclusion The HSF model for photoaging shows obviously abnormal appearance and stagnant growth with increased degree of senescence and decreased autophagy compared with normal control HSFs. Key words: Autophagy;  Skin aging;  Fibroblasts