P32 Restoring the ageing skin barrier in vitro

Abstract The skin provides an essential barrier to the body. As we age, the make-up of this barrier changes, with a reduction of stratum corneum lipids. This loss of lipids as we age can lead to the formation of dry and easily damaged skin, allowing for water loss from the skin surface. One mechanism for this reduction in stratum corneum lipids is dysfunctional lipid transport. To investigate lipid transport within the skin we have developed a two-dimensional high-throughput cholesterol transport assay. Using this assay we have screened 200 naturally occurring compounds and 800 plant extracts to determine their ability to improve cholesterol transport. We identified seven compounds that were able to increase cholesterol transport with no cellular toxicity. Three compounds were selected for further testing in three-dimensional (3D) organotypic skin models with or without defects in cholesterol transport and stratum corneum lipids. Three-dimensional organotypic skin models were grown for 7 days before daily treatment with either dimethyl sulfoxide or 1 µmol L–1 of the selected compound for an additional 7 days. Immunofluorescent staining was conducted to assess skin differentiation (K14, K10, TGM1), proliferation (Ki67), basement membrane (laminin α3) and stratum corneum lipids (Nile red). We have developed a 2D screening and 3D testing platform to assess compounds and drugs for their effect on cholesterol transport. Compounds that can target cholesterol transport within keratinocytes could be a beneficial treatment to help improve the ageing skin barrier, improving dry and damaged skin.