The Effect of Rhus verniciflua Stokes Extracts on Photo-Aged Mouse Skin

BACKGROUND Rhus verniciflua Stokes (RV) has traditionally been used in Korea as an indigenous food (Rhus chicken soup) and as an herbal medicinal plant. While the anticancer, antimicrobial, and anti-inflammatory properties of RV have been actively studied in the medical field, its antioxidant effects in the skin that resist the reactive oxygen species in keratinocytes and fibroblasts is less understood. OBJECTIVE We designed to evaluate the effects of R. verniciflua Stokes extract (RVE) on the photo-aged skin by an in vitro experiment using human fibroblasts and an in vivo experiment using a photo-aged murine model. METHODS For the in vitro experiments, human fibroblasts irradiated with ultraviolet (UV) B were treated with RVE or vehicle, and the growth levels and the expression level of type 1 procollagen were compared. For the in vivo experiment, photo-aged mice irradiated with UVB and UVA were administered drinking water with or without RVE, and histological changes and the expression level of type 1 procollagen and matrix metalloprotease (MMP)-13 were compared. RESULTS In vitro experiments using fibroblasts irradiated with UVB showed that RVE promoted growth and significantly increased the expression of type 1 procollagen as compared to the control group. In the photo-aged mice, RVE increased collagen content in the dermis and promoted the synthesis of type 1 procollagen without any visible decrease in MMP-13 as compared to control group. CONCLUSION In addition to the previously reported antioxidant effects of RVE, oral intake of RVE effectively inhibited photo-aging in hairless mice by enhancing collagen synthesis.