RÉSUMÉ
Objective:To determine the effect of Lentinula edodes extract on ultraviolet (UV) A and UVB-induced changes in matrix metalloproteinase (MMP) and typeⅠprocollagen expression using human immortalized HaCaT keratinocytes. Methods:Lentinula edodes ethanol extract (LEE) was obtained by extraction with 80％ ethanol for 4 h at 80 ℃. Effect of LEE on UV-induced alteration on the expression and production of MMPs and typeⅠprocollagen in keratinocytes was investigated using ELISA, RT-PCR, and Western blotting assay. To determine the underlying mechanism of LEE-mediated effects, mitogen-activated protein kinase (MAPK) and activator protein 1 signaling pathways were analysed by Western blotting assay. Results:LEE significantly inhibited the expression of MMP-1 and MMP-9 and increased the expression of typeⅠprocollagen in UVA and UVB-irradiated HaCaT keratinocytes. The phosphorylation levels of p38 were significantly inhibited by LEE whereas it did not affect c-Jun N-terminal kinase and extracellular signal-regulated kinase phosphorylation. Suppression of p38 phosphorylation was also accompanied by downregulation of UVA and UVB-induced increase in c-Fos. Conclusions:LEE effectively inhibits the expression of MMP-1 and MMP-9 and increases typeⅠprocollagen production through the p38 MAPK/c-Fos signaling pathway in UVA and UVB-irradiated HaCaT keratinocytes. This findings suggest that Lentinula edodes may be developed as a cosmetic material to suppress UV exposure-mediated skin aging.