Skin penetration and UV-damage prevention by nanoberries

Abstract

Background: Ethanolic extract from blueberry (Vaccinium myrtillus) is rich in anthocyanins and thus exhibits antioxidant activity. On the other hand, ultradeformable liposomes are capable of penetrating to the impermeable barrier of skin. Nanoberries are ultradeformable liposomes carrying blueberry extract. Objectives: In this study, their capacity to penetrate the stratum corneum and photodamage prevention were tested, with the aim of developing a topical formulation for skin protection from environmental damage. Methods: Nanoberries were prepared by lipid film resuspension with ethanolic extract from blueberry, followed by sonication and incorporation to a gel. Size, zeta potential, deformability, rheology and viscoelasticity were determined. Toxicity was assessed in vivo in zebrafish model, while in vitro cytotoxicity assay was performed on HaCaT and HEK-293T cell lines. Skin penetration was evaluated with the Saarbrücken Penetration Model followed by tape stripping, cryosection or optical sectioning. UV-damage and photoprotection were determined by ad-hoc methods with UVA, UVB and UVC radiation on HaCaT cells. Wound assay was performed on HaCaT cells. Results: Nanoberries of about 100 nm, with differential elastic properties, did penetrate the stratum corneum, with low toxicity. When HaCaT cells were exposed to UV radiation in presence of nanoberries, their viability was mantained. Conclusions: Nanoberries could be effective to protect the skin from sun photodamage.