Improvement of Human Epidermal Barrier Structure and Lipid Profile in Xerotic- and Atopic-Prone Skin via Application of a Plant-Oil and Urea Containing pH 4.5 Emulsion

Abstract

Epidermal barrier dysfunction can lead to xerotic skin and promote skin disorders like atopic dermatitis. Atopic skin is characterized by reduced water-retaining compounds, altered lipid composition and elevated skin pH. Against this background, a study was conducted to investigate the impact of a specific skin care product on epidermal barrier function in dry and atopic-prone skin. A marketed pH 4.5 cosmetic formulation containing 10% urea and specific plant oils was evaluated on 25 subjects with dry and atopic-prone skin. Measurements of skin hydration, pH, and barrier function were performed before and after 3 weeks of product usage. Additionally, visual scoring and stratum corneum lipid analysis using electron microscopy were conducted to investigate lipid composition. An improved skin hydration compared to the untreated area and a tendency to decrease the baseline elevated skin surface pH were observed. The visual scoring showed reduced dryness, roughness, and tension through the application. Furthermore, the stratum corneum lipid matrix was improved in terms of lipid content and organization. The combination of an acidic product’s pH, a relevant urea content and effective plant oils is shown to be beneficial in terms of improving the skin barrier function, structure and appearance and is recommended for dry and atopic-prone skin.

Protective and Regenerative Anti-Pollution Efficacy of a Plant Oil-Based Day and Night Cream: Investigated by a Novel Approach to Reveal the Impact of Pollutants on Epidermal Barrier Integrity and Lipid Matrix

“…The normalized length of lipid lamellae in the intercellular space (nICLL) as a marker for the integrity of the epidermal barrier was determined by the noninvasive skin sampling technique Lipbarvis ® (Microscopy Services Dähnhardt GmbH, Flintbek, Germany). The Lipbarvis ® procedure has been described several times in the literature and has been applied in quite a few studies [32] [33] [34]. A special glue-carrier system is used to remove the corneocytes from the skin surface.…”

Topical Peroxisome Proliferator-Activated Receptor Agonist Induces Molecular Alterations Enhancing Barrier Function and Water-Holding Capacity of the Human Stratum Corneum In Vivo

“…Cosmetics offer moisturising, strengthening, and nourishing effects that target the SC exclusively. The strengthening effect is related to the enhancement of the skin barrier function and is mainly associated with the topical application of lipids [51,52]. It is known that peroxisome proliferator-activated receptors (PPARs) are nuclear hormone receptors and comprise three different isoforms, namely PPAR-α, PPAR-γ, and PPAR-β/δ, which are activated by fatty acids and their derivatives [53].…”

Looking into the Skin in Health and Disease: From Microscopy Imaging Techniques to Molecular Analysis

“…Stratum corneum plays a fundamental role in the barrier function of the skin, which depends critically on its molecular architecture [ 1 , 87 , 88 , 89 , 90 ]. For example, significant alterations in the structure of the stratum corneum and in its lipid composition were identified in skin conditions with an impaired barrier function, such as atopic dermatitis [ 91 , 92 , 93 , 94 , 95 , 96 , 97 , 98 , 99 ].…”