Grape skin extract prevents UV irradiation induced DNA damage of normal human epidermal keratinocytes cells

BACKGROUND: There is concern that DNA damage may occur in skin cells due to UV irradiation. In this study, we investigated whether extracts from grape skin, which should be discarded, can suppress DNA damage caused by UV radiation. OBJECTIVE: This study aims to investigate the effectivity of GSE in diminishing UV-induced cytotoxicity in normal human epidermal keratinocytes (NHEK) cells. METHODS: The polyphenol content in GSE was carried out using the HPLC instrument. UV dose was selected by measurement of cell viability, and ELISA results of DNA photoproduct. Optimum extracts condition of grape skin selected by DNA photoproduct content as well as at this condition; Bax/Bcl-2 ratio and cytochrome c gene expressions were evaluated by Western blotting. RESULTS: In this study, we confirmed that GSE protect against DNA damage-induced cell death. Condition for 80% EtOH for 24 h at 60 °C was suitable to extract for grape skin. Red grape skin (Zweigelt) was more effective than white grape skin (Niagara) in preventing (before irradiation) and repairing (after irradiation). UV-induced upregulation of Bax/Bcl-2 ratio and cytochrome c expression were reduced by GSE treatment. CONCLUSIONS: The study demonstrated a promising potential of GSEs in skin therapeutics application.