Anti-Photoaging Activity of Scutellaria barbata D. Don (Family Lamiaceae) on Ultraviolet B-Irradiated NIH-3T3 Skin Fibroblast and SKH-1 Hairless Mouse

Abstract

We investigated whether Scutellaria barbata D. Don (Family Lamiaceae) (SBD), a traditional medicine used for heat clearing and detoxification, possesses antiphotoaging properties. Pretreatment of NIH-3T3 skin fibroblast cells with non-toxicological levels of water extract of SBD (WESBD) and ethanol extract of SBD (EESBD) restored the expression of procollagen type-1 (COL1A1), matrix metalloproteinase-1a (MMP-1a), interleukin-6 (IL-6), interleukin-8 (IL-8), and monocyte chemotactic protein-3 (MCP-3) genes following abnormal expression induced by ultraviolet B (UVB) irradiation. WESBD/EESBD administration to the dorsal skin area of hairless mice significantly (p < 0.05) inhibited UVB-induced wrinkle formation and epidermal thickness. The WESBD and EESBD treatments also restored the dermal collagen content, which was decreased by the UVB treatment, and normal COL1A1 and MMP-1a expression. Interestingly, both the WESBD and EESBD pretreatments significantly attenuated UVB-induced phosphorylation of protein kinase B (AKT) but not that of mitogen-activated protein kinases (MAPKs). This finding indicates that the antiphotoaging effects of WESBD and EESBD may be related to attenuation of UVB-induced overactivation of AKT phosphorylation. High performance liquid chromatography (HPLC) and mass spectrometry analysis revealed that isorhamentin and scutebarbatine I were major single components of EESBD. These results suggest that WESBD and EESBD may have potential in development as antiphotoaging agents.