ABSTRACT
Objective To investigate the role of cathepsin G in photoaged fibroblasts. Methods Human fibroblasts were cultured and induced to premature senescence using UVA + MOP methods. Senescence-associated-β-galactosidase (SA-β-gal) stain was used to evaluate the positive rate of aged cells. The mRNA and protein expression of cathepsin G in photoaged fibroblasts were detected by real-time RT-PCR and Western blot techniques. Results Over 98 % induced cells presented a positive SA-β-gal straining. The expression of cathepsin G, detected by Western blot, was increased to (1. 70±0. 028) times of the control. And RT-PCR revealed that the synthesis of cathepsin G mRNA was also up-regulated to 1. 42±0. 09. Conclusion The results of our study demonstrates a significant correlation between photoaged fibroblasts and cathepsin G. The up-regulation of cathepsin G may play an important role in the damages of extracellular matrix and activation of MMPS in photoaged human skin.