Abstract
Ultraviolet-B (UVB) irradiation causes skin damage via deleterious effects including oxidative stress, inflammation, and collagen degradation. The photoprotective effects of a hyperoside-enriched fraction obtained from Houttuynia cordata Thunb. (H. cordata) on the attenuation of UVB-induced skin aging in human fibroblasts were investigated. The solvent-partition technique was used to establish the hyperoside-enriched fraction of H. cordata (HcEA). The active compounds identified in the H. cordata extracts were hyperoside, quercitrin, chlorogenic acid, and rutin. With regard to the photoprotective effects of H. cordata on UVB-irradiated dermal fibroblasts, HcEA and hyperoside inhibited intracellular ROS production and inflammatory cytokine secretions (IL-6 and IL-8), while increasing collagen type I synthesis along with downregulating MMP-1 gene and protein expressions. Mechanistically, the hyperoside-enriched fraction obtained from H. cordata inhibited UVB-irradiated skin aging through regulation of the MAPK signaling pathway by attenuating the activation of JNK/ERK/c-Jun in human dermal fibroblasts. The hyperoside-enriched fraction of H. cordata exerted potent anti-skin aging properties against UVB exposure. The findings of this study can be applied in the cosmetics industry, as H. cordata extract can potentially be used in pharmaceutical or cosmetic formulations as a photoprotective or anti-skin aging agent.