Unsaponifiable matter (USM) from perilla seed meal contains numerous phytochemicals, including tocopherols, phytosterols, squalene, and policosanols, that exhibit antioxidant and health-promoting properties. In this study, the protective effects of USM on UVB-induced skin aging were investigated in Hs68 cells. UVB irradiation decreased cell viability by 26% compared to the control. However, USM blocked UVB-induced cytotoxicity. Moreover, USM treatment significantly decreased the UVB-induced production of reactive oxygen species and attenuated the UVB-induced production and mRNA expression of matrix metalloproteinases (MMPs) by inhibiting the phosphorylation of mitogen-activated protein kinases and activator protein 1 (AP-1). Furthermore, UVB exposure led to a 49.4% reduction in collagen synthesis. However, USM treatment restored collagen synthesis through upregulation of the transforming growth factor beta (TGF-β)/Smad2/3 pathways. These data indicate that USM regulates the production of MMPs and collagen by modulation of the TGF-β/Smad pathway and AP-1 activity, suggesting that USM may be a useful anti-photoaging ingredient.
Keywords: collagen; perilla seed meal; photoaging; skin; unsaponifiable matter.