Protective effect of Disporum sessile D.Don extract against UVB-induced photoaging via suppressing MMP-1 expression and collagen degradation in human skin cells

• DDE inhibited UVB-induced MMP-1 expression in NHDF and HaCaT cells.
• DDE reduced UVB-induced collagen degradation in NHDF.
• DDE reduced UVB-induced phosphorylation of MAP kinases and IκBα.
• DDE inhibited UVB-induced translocation and activation of NF-κB in HaCaT cell.
• Our results suggest that DDE may be utilized for the skin protection against UV irradiation.

In the present study, we report that Disporum sessile D.Don herbal extract (DDE) possesses anti-skin photoaging effect through inhibition of MMP-1 mRNA and protein expression levels and increase collagen production in UVB-irradiated human dermal fibroblast cells (NHDF). To delineate the molecular mechanism by which DDE inhibited MMP-1 expression, immortal human keratinocytes cells (HaCaT) have been used. We have found that DDE inhibited UVB-induced MMP-1 mRNA and protein expression levels in HaCaT cells through inhibition of UVB-induced activation of NF-κB in HaCaT cells. Inhibitors of NF-κB (Bay11-7082), and mitogen-activated protein kinases such as extracellular regulated kinase (PD98059), c-Jun N-terminal kinase (SP600125), and p38 (SB203580) suppressed expression of MMP-1, and phosphorylation of these signaling molecules were attenuated by DDE. DDE also inhibited phosphorylation of IKKα and IκBα, and reduced nuclear translocation of NF-κB. Our results also demonstrated that DDE inhibited NF-κB driven expression of luciferase reporter gene and the DNA binding of NF-κB to its cognate binding site in UV-irradiated cells. Therefore, these results strongly suggest that DDE can be utilized as a potential agent for prevention and treatment of skin photoaging.