Skin pigmentation improvement with resveratrol microemulsion gel using polyoxyethylene hydrogenated castor oil

Abstract

Objective To investigate the safety and efficacy of resveratrol microemulsion gel in improving pigmentation. Methods Resveratrol microemulsion gel was prepared by the microemulsion solubilization method, and its quality was evaluated. The transdermal and drug retention rates of resveratrol in vivo were assessed using a transdermal test. The inhibitory effects of resveratrol suspension and microemulsion on tyrosinase activity and melanin production of A375 human melanocytes and zebrafish embryos were compared. A skin patch test was used to investigate the safety of the gel on 15 volunteers. Results The microemulsion gel was homogeneous and stable. Compared with suspension and microemulsion, the drug penetration rate and skin retention in the microemulsion gel group were significantly increased. Compared with the suspension group, the activity of melanocyte tyrosinase in A375 human melanocyte was significantly inhibited in the microemulsion group, and the melanin production rate of A375 human melanocyte and the melanin area of zebrafish yolk was decreased. All 15 volunteers tested negative for the human skin patch. Conclusions The microemulsion gel could significantly enhance the ability of resveratrol to inhibit the formation of melanin without causing side effects. These data provide the experimental basis for developing and applying the preparation for improving pigmentation.