Safe Retinol-Like Skin Biological Effect by a New Complex, Enriched with Retinol Precursors

Background: Retinol (RE) is deeply involved in skin processes, therefore it is widely formulated in cosmetics, primarily as an anti-aging ingredient. Despite its efficacy, the safety profile of RE is controversial. Objectives: Pretinol (PRE) complex was formulated with two RE precursors, β-Carotene and Niacinamide, in order to deliver retinol-like skin benefits with healthier characteristics, assuming that skin enzymes will enable safe RE supply on spot. Methods: The expression levels of hyaluronic acid, Tumor Necrosis Factor alpha (TNFα) and Interleukin 1 alpha (IL-1α), were measured using various skin models before and after exposure to PRE and RE. Full genome microarray was performed and the affected genes and pathways were analyzed. Results: Following fibroblasts exposure to PRE, the natural synthesis of hyaluronic acid is significantly elevated. Skin safety, demonstrated via cytokines expression on ex-vivo skin, results with TNFα and IL-1α elevation by RE application. In contrary PRE significantly reduces TNFα while IL-1α is not affected. These results establish skin safety advantage of PRE vs RE. Microarray results examined on skin equivalents reveal the involvement of PRE in inflammatory attenuation. Conclusions: Formulating RE precursors as a safe source for RE is partially supported. PRE presents a skin benefit in parallel to RE, while PRE characteristics are suggested to be safer to skin.