Neryl acetate, the major component of Corsican Helichrysum Italicum essential oil, mediates its biological activities on skin barrier

Abstract

ABSTRACTCorsican Helichrysum Italicum essential oil is characterized by high concentrations of neryl acetate, and we previously demonstrated that Corsican Helichrysum Italicum essential oil increases the expression of genes that are part of the differentiation complex (involucrin, small proline rich proteins, late cornified envelope, S100 protein family). The biological activities of Helichrysum Italicum essential oil and neryl acetate were compared to identify how neryl acetate contributes to Helichrysum Italicum essential oil activity on human skin. Neryl acetate, as a part component of Helichrysum Italicum essential oil, was tested on skin explant models for 24 hours and 5 days in comparison with Helichrysum Italicum essential oil. We analyzed the biological regulations in the skin explant by transcriptomic analysis, skin barrier protein immunofluorescence, lipid staining and ceramide analysis by liquid chromatography-mass spectrometry. Transcriptomic analysis revealed that 41.5% of Helichrysum Italicum essential oil-modulated genes were also regulated by neryl acetate and a selected panel of genes were confirmed by quantitative reverse transcription PCR analysis. Those genes are involved in epidermal differentiation, skin barrier formation and ceramide synthesis. Involucrin, involved in formation of the cornified envelope, was upregulated at both gene and protein levels after 24 hours and 5 days respectively. After 5 days of treatment, total lipids and ceramides were also increased. Our results demonstrate that neryl acetate mediates a large part of Corsican Helichrysum Italicum essential oil activity on skin barrier formation.