Effects of petrolatum, a petrolatum depositing body wash and a regular body wash on biomarkers and biophysical properties of the stratum corneum.

BACKGROUND: An important trend in the personal care industry involves the development of body wash products that not only clean the skin without damage but deposit conditioning ingredients to improve skin barrier function. OBJECTIVE: The objective of this study was to develop skin biomarker measures to quantify the treatment effects of body wash products. METHODS: We employed analysis of structural proteins (keratin 1,10,11 and involucrin), a natural moisturizing factor (pyrrolidone carboxylic acid) and an inflammatory mediator (IL-1ra/IL-1α) from adhesive discs with dry skin grading, TEWL and capacitance measurements to compare the effects of direct application of petrolatum, a high petrolatum depositing body wash, and a regular body wash on dry leg skin in a standard leg-wash treatment protocol. RESULTS: High depositing body wash and petrolatum had positive effects on stratum corneum barrier function as judged by biomarker analysis, biophysical measurements and skin grading compared to the regular body wash product. CONCLUSIONS: The results clearly indicate that a combination of biomarker and biophysical property measurements is effective for determining the skin benefits of moisturizing body wash products.

CONTEXTE: Une tendance importante dans l'industrie des soins personnels inclut le développement de produits de lavage corporel qui non seulement nettoient la peau sans l'endommager, mais déposent des ingrédients de traitement pour améliorer la fonction de la barrière cutanée. OBJECTIF: L'objectif de cette étude était de développer des mesures de biomarqueurs cutanés permettant de quantifier les effets du traitement des produits de lavage corporel. MÉTHODES: Nous avons utilisé l'analyse de protéines structurelles (kératine 1,10,11 et involucrine), un facteur hydratant naturel (acide carboxylique de pyrrolidone) et un médiateur inflammatoire (IL-1ra/IL-1a) provenant de disques adhésifs avec cotation de la sécheresse cutanée, mesures de perte d'eau transépidermique (transepidermal water loss, TEWL) et de capacitance pour comparer les effets de l'application directe de vaseline, d'un produit de lavage corporel avec dépôt élevé de vaseline et d'un produit de lavage corporel ordinaire sur la peau sèche des jambes, dans un protocole de traitement de lavage des jambes standard. RÉSULTATS: Le produit de lavage corporel à dépôt élevé et la vaseline avaient des effets positifs sur la fonction de barrière de la couche cornée, comme évalué par l'analyse des biomarqueurs, les mesures biophysiques et la cotation de la peau, comparé au produit de lavage corporel ordinaire. CONCLUSIONS: Les résultats indiquent clairement qu'une combinaison de mesures des biomarqueurs et des propriétés biophysiques est efficace pour déterminer les bienfaits pour la peau des produits de lavage corporel hydratants.

Proteomic and Bioinformatic Analyses for the Identification of Proteins With Low Allergenic Potential for Hazard Assessment.

Use of botanicals and natural substances in consumer products has increased in recent years. Such extracts can contain protein that may theoretically represent a potential risk of IgE-mediated allergy. No method has yet been generally accepted or validated for assessment of the allergenic potential of proteins. For development of suitable methods datasets of allergenic and nonallergenic (or low allergenic) proteins are required that can serve, respectively, as positive and negative controls. However, data are unavailable on proteins that lack or have low allergenic potential. Here, low allergenic potential proteins are identified based on the assumption that proteins with established human exposure, but with a lack of an association with allergy, possess low allergenic potential. Proteins were extracted from sources considered to have less allergenic potential (corn, potato, spinach, rice, and tomato) as well as higher allergenic potential (wheat) regarding common allergenic foods. Proteins were identified and semi-quantified by label-free proteomic analysis conducted using mass spectrometry. Predicted allergenicity was determined using AllerCatPro (https://allercatpro.bii.a-star.edu.sg/). In summary, 9077 proteins were identified and semi-quantified from 6 protein sources. Within the top 10% of the most abundant proteins identified, 178 characterized proteins were found to have no evidence for allergenicity predicted by AllerCatPro and were considered to have low allergenic potential. This panel of low allergenic potential proteins provides a pragmatic approach to aid the development of alternative methods for robust testing strategies to distinguish between proteins of high and low allergenic potential to assess the risk of proteins from natural or botanical sources.

Effects of season stratum corneum barrier function and skin biomarkers.

The skin on the lower legs of 25 female subjects was evaluated first in the winter, and then again in the summer of the same subjects. Barrier function was determined by measuring transepidermal water loss (TEWL), and skin hydration and dryness were evaluated by electrical measurements (Corneometer ® CM825) and visual grading. Stratum corneum (SC) was sampled using 10 sequential D-Squame sampling discs and analyzed for 2-pyrrolidone-5-carboxylic acid (PCA), keratin-1,10,11, interleukin 1α (IL-1α), interleukin 1 receptor antagonist (IL-1ra), selected ceramides, cholesterol, cholesterol sulfate, and selected free fatty acids. TEWL as well as the visual dryness grades were significantly lower in the summer while hydration was higher. PCA was significantly higher in the summer as were the keratins. The ratio IL-1ra:IL-1α, an indicator of skin inflammation, was significantly lower in the summer. The amount of protein removed by the tape strips was also significantly lower in summer indicating better SC cohesion. Among the SC lipids measured, total ceramides, individual ceramides, total fatty acids, and cholesterol were higher in summer compared to winter. Stearic acid and cholesterol sulfate were not significantly different between winter and summer.

Epidermal changes associated with symptomatic resolution of dandruff: biomarkers of scalp health.

BACKGROUND: Dandruff is a common scalp condition characterized by flakes, pruritus and sometimes mild erythema. These symptoms reflect underlying histopathologic and biochemical events that must be reversed if treatment is to be effective. OBJECTIVES: This study aimed to better characterize the state of the epidermis in dandruff and to determine how a defined set of skin surface biomarkers of this state change during a successful course of treatment with a potentiated zinc pyrithione (ZPT) shampoo. METHODS: A population of dandruff sufferers was treated for 3 weeks with a commercial ZPT shampoo or a non-medicated product, and the effect of treatment on adherent scalp flake (ASF) scores was evaluated. Biopsies were taken from lesional sites at baseline and at the end of the study for histomorphometric and histopathologic analysis. Stratum corneum (SC) samples were likewise obtained for evaluation of biochemical markers of inflammation (IL-1α, IL-1RA, IL-8) and barrier integrity (keratin 1, 10, 11; involucrin; SC lipids; human serum albumin). The biomarker profile was evaluated first by comparison with that in non-dandruff subjects at baseline, and then to determine whether any treatment-induced changes were correlated with reductions in flaking in dandruff sufferers. RESULTS: Taken together, our studies showed that treatment with the ZPT shampoo led to an improvement in the overall scalp condition as assessed by the resolution of flaking, reduction in epidermal thickness and inflammatory biomarkers, and a dramatic improvement in biomarkers of epidermal barrier integrity. CONCLUSIONS: The combination of biomarkers examined appears to be a good overall descriptor of the health of the scalp in dandruff, and changes in these biomarkers track with tissue-level events that underlie clinical efficacy in the treatment of dandruff by ZPT shampoo. For the first time, we demonstrate a set of tools that extend beyond flaking scores to provide insight into specific biological changes occurring on the scalp to enable an objective assessment of scalp health.