A new dexpanthenol-containing liquid cleanser for atopic-prone skin: Results from two prospective clinical studies evaluating cutaneous tolerability, moisturization potential, and effects on barrier function.

BACKGROUND: Gentle cleansing of the skin without further compromising its barrier function and moisture content and being simultaneously devoid of adverse effects on the skin microbiome are important features of body cleansers for atopic-prone skin sufferers. For this population, a new dexpanthenol-containing liquid cleanser (DCLC) was developed. METHODS: Two prospective 4-week studies have been conducted. Study 1 investigated the effect of once-daily DCLC on stratum corneum (SC) hydration, transepidermal water loss (TEWL), skin pH, and skin microbiome (all on the volar forearm) in adult subjects with dry skin (N = 44). Study 2 explored the cutaneous tolerability of DCLC and its effect on the microbiome biodiversity of the volar forearm skin in infants/children with atopic-prone skin (N = 33, aged 6 months to 6 years). In the latter study, DCLC was applied 2-3 days/week in combination with an emollient applied at least twice daily. RESULTS: In Study 1, on Day 29, the mean change in skin surface capacitance from baseline was significantly greater in the forearm test area treated with DCLC than in the contralateral test area (control) treated with water only (5.16 vs. 3.65 a.u.; p = 0.011), suggesting long-term SC hydration. DCLC use was not associated with changes in TEWL, skin pH, or microbiome biodiversity if compared to control. In Study 2, the 4-week use of DCLC in combination with an emollient was well tolerated according to pediatrician skin assessment, and no flare-ups were recorded. The microbiome biodiversity did not shift during the study. CONCLUSION: These findings support the use of DCLC in subjects with atopic-prone skin.

New methods for assessing secondary performance attributes of sunscreens suitable for professional outdoor work.

BACKGROUND: Outdoor workers (OW) are highly exposed to solar ultraviolet radiation (UVR) and thus at increased risk for developing skin cancer. An essential part of an overall strategy to reduce workplace UVR-exposure to OW's skin is the usage of sunscreens. However, compliance with regular sunscreen usage seems to be low, as products are usually designed for recreational sun exposure and thus do not meet the requirements of physically active OW. To date, no standardized test procedures assess the suitability of sunscreens for professional use. The aim of this pilot study was to develop standardized methods of testing secondary performance attributes (PA) to represent real-life working conditions of outdoor work. METHODS: Ten sunscreen products, carefully selected after a detailed market survey of all relevant producers available on the German market, were evaluated regarding their suitability for professional outdoor work on 24 healthy volunteers in a newly designed test procedure. In addition to three standardized efficacy characteristics, i.e., sun protection factor, water-resistance, and UVA protection, we evaluated each PA involving parameters typically associated with outdoor workplaces. RESULTS: We developed standardized methods for objectifying the suitability of sunscreen products for professional outdoor work. The test procedures used are well feasible and appropriate for testing the PA because they represent practical working conditions in detail - although the degree of discriminability of single test methods varied. The claimed sun protection factor (SPF) of the products was confirmed; bio-stability of the SPF after physical activity was achieved in most cases. While most products hardly irritate the eyes and are quickly absorbed, the evaluation of the subjective skin feeling and non-slip grip is inconsistent. CONCLUSIONS: In this pilot study, for the first time secondary PA are defined and examined. Although further objectification of the PA assessment as well as the establishment of minimum standards should be sought, the new methods could already complement the so far mandatory labels and in this way provide a significant impetus for the current scientific and political focus on the improvement of occupational health in highly UVR-exposed OW.

Anti-pollution effects of two antioxidants and a chelator-Ex vivo electron spin resonance and in vivo cigarette smoke model assessments in human skin.

BACKGROUND: Skin damage arising from pollutants in gaseous and particulate matter forms is mainly mediated by oxidative stress. The pollutants directly or indirectly generate free radicals on and in the skin, leading, for example, to MMP up-regulation and damage of collagen fibers. Antioxidants and chelators are used in anti-pollution cosmetics to reduce the harmful effects of free radical generation. MATERIALS AND METHODS: We investigated the efficacy of two antioxidants and one chelator in an anti-pollution cigarette smoke model. Free radical generation was measured directly after UV and cigarette smoke exposure ex vivo on pig skin (slaughterhouse waste), by use of Electron Spin Resonance (ESR). Effects of cigarette smoke were compared to those of Urban Dust (NIST-standard). ESR was also used to measure the copper chelation activity of the test products. Following cigarette smoke application in vivo, two markers of lipid peroxidation malondialdehyde (MDA), and squalene monohydroperoxide (SQOOH), were measured from swab solutions taken from the smoke-exposed skin sites. RESULTS: EDTA generated no effect and the non-chelator antioxidant Tocopherol only small antioxidant effects after exposed to cigarette smoke ex vivo as well as in vivo. Only the hydrophilic phenylethanoid H1 showed significant effects. A clear reduction of free radicals ex vivo and further a significant reduction of in vivo lipid peroxide formation was measured. CONCLUSION: The cigarette smoke model is an ideal method for in vivo assessment of anti-pollution efficacy of topical products with close relation to the real situation of subjects exposed to urban pollution. Further research is required to better understand the role of chelators in anti-pollution cosmetics.

Targeted dry skin treatment using a multifunctional topical moisturizer.

OBJECTIVE: The development of dry skin is a complex process, with a wide variety of factors each playing different roles in its evolution. Given this, it is important when designing a formulation to tackle dry skin that these varied aspects of skin behaviour are addressed. Presented here are the results of a 3-week moisturization study carried out on dry legs. A wide range of traditional and more recently developed biophysical measurement methods have been combined with visual assessment of skin condition to enable multiple aspects of skin function to be determined. The observed changes in the skin are discussed in terms of the ingredients used in the moisturizing formulation. METHODS: A range of novel and traditional skin assessment methods and techniques were used to assess the effects of an oil in water-based moisturizing product compared to an untreated site during a 3-week in vivo study on dry lower leg skin. RESULTS: Statistically significant improvements were observed in a range of skin parameters as a result of product usage. Skin hydration assessed using Corneometer®, Epsilon® and visual dry skin grading all increased after 3 weeks of use. Skin barrier function measured using transepidermal water loss also improved. Levels of cholesterol, free fatty acids and Ceramide NH increased, as well as the average length of the stratum corneum (SC) lipid lamella bilayers, and the ratio of lipid to protein increased (measured using Lipbarvis® and in vivo Confocal Raman Spectroscopy). Increases in the levels of Ceramide EOS and NP were also observed, along with an improvement in corneocyte maturity, although these were not statistically significant. CONCLUSIONS: Using a variety of traditional and novel skin assessment techniques, a wide range of factors associated with the evolution of dry skin have been assessed upon treatment with a new topical moisturizer. Product usage resulted in significant improvements to skin hydration and barrier function, the levels and morphology of SC barrier lipids, and overall epidermal differentiation. As a result there was a significant reduction in the characteristics associated with the development of dry skin after use of the test product.

OBJECTIF: le développement de la sécheresse cutanée est un processus complexe, une grande variété de facteurs jouant chacun des rôles différents dans son évolution. De ce fait, il est important d'aborder ces différents aspects du comportement de la peau lors de la conception d'une formulation pour lutter contre la sécheresse cutanée. Les résultats d'une étude de 3 semaines sur l'hydratation des jambes sèches sont présentés ci-dessous. Un large éventail de méthodes de mesure biophysiques traditionnelles et plus récemment développées ont été combinées à une évaluation visuelle de l'état de la peau pour permettre de déterminer de multiples aspects de la fonction cutanée. Les changements observés sur la peau sont abordés en termes des ingrédients utilisés dans la formulation hydratante. MÉTHODES: une série de méthodes et de techniques nouvelles et traditionnelles d'évaluation de la peau ont été utilisées pour évaluer les effets d'un produit hydratant à base d'émulsion huile dans eau par comparaison à un site non traité au cours d'une étude in vivo de 3 semaines sur la peau sèche de la partie inférieure des jambes. RÉSULTATS: des améliorations statistiquement significatives ont été observées au niveau d'une gamme de paramètres cutanés suite à l'utilisation du produit. L'hydratation cutanée évaluée à l'aide de Corneometer®, Epsilon® et de la cotation visuelle de la sécheresse cutanée s'est améliorée selon toutes ces méthodes après 3 semaines d'utilisation. La fonction de barrière cutanée mesurée d'après la perte d'eau transépidermique s'est également améliorée. Les taux de cholestérol, d'acides gras libres et de céramides NH ont augmenté, ainsi que la longueur moyenne des bicouches des lamelles lipidiques de la couche cornée (CC), et il en a été de même pour le rapport lipide/protéine (mesuré à l'aide du Lipbarvis® et de la spectroscopie confocale de Raman in vivo). Des augmentations des taux de céramides EOS et NP ont également été observées, ainsi qu'une amélioration de la maturité des cornéocytes, bien qu'elles n'aient pas été statistiquement significatives. CONCLUSION: à l'aide d'une gamme de techniques d'évaluation de la peau traditionnelles et nouvelles, un large éventail de facteurs associés à l'évolution de la sécheresse cutanée a été évalué lors du traitement avec un nouveau produit hydratant topique. L'utilisation du produit a entraîné une amélioration significative de l'hydratation et de la fonction de barrière de la peau, des taux et de la morphologie des lipides de la barrière SC , et de la différenciation épidermique globale. Cela a entraîné une amélioration significative des facteurs associés au développement de la sécheresse cutanée.

A Dermonutrient Containing Special Collagen Peptides Improves Skin Structure and Function: A Randomized, Placebo-Controlled, Triple-Blind Trial Using Confocal Laser Scanning Microscopy on the Cosmetic Effects and Tolerance of a Drinkable Collagen Supplement.

The purpose of this randomized, placebo-controlled, triple-blind trial on 60 healthy female volunteers was to assess the cosmetic effects on skin quality of a food supplement containing special collagen peptides together with acerola extract, vitamin C, vitamin E, biotin, and zinc after an intake of 12 weeks (Elasten®, QUIRIS Healthcare, Germany). To reduce assessment bias maximally and increase the accuracy and objectivity of the outcomes, the trial design was triple blinded in a manner that neither the subjects nor the person administering the products nor the person who assessed the primary outcomes knew which subjects had received the test product and which had received the placebo. The expert grader assessing the confocal laser scanning microscopy images was additionally blinded regarding the time when the image was taken (on days 1 or 85). The objective, blinded, and validated image analyses using confocal laser scanning microscopy showed a significant improvement of the collagen structure of facial skin (primary endpoint) after intake of the test product, while no improvements were found after intake of the placebo. The proven positive nutritional effect on the collagen structure was fully consistent with positive subjective evaluations of relevant skin parameters such as elasticity, crinkliness/wrinkliness, and evenness in different body areas such as face, hands, décolleté, neck, backside, legs, and belly, all serving as secondary endpoints. The test product was found to be safe and very well tolerated. A cosmetically relevant improvement of the facial skin was demonstrated after administration of the collagen supplement.

Characterization and validation of an in vivo confocal Raman spectroscopy led tri-method approach in the evaluation of the lip barrier.

BACKGROUND/AIM: It was the aim to establish and validate in vivo confocal Raman spectroscopy for characterization of the lip barrier in conjunction with transepidermal water loss (TEWL) and skin capacitance assessments. For the first time in vivo, barrier-relevant components of the lip (derived, natural moisturizing factors (NMFs) and ceramides are described. METHODS: In 32 healthy volunteers, a dental tongue fixation device was inserted to prevent both voluntary and involuntary lip moisturization during measurements. Seventeen individual parameters relating to water, ceramide, and NMF content were assessed via Raman spectroscopy. Additionally, corneometry and TEWL were measured. To give a guidance for the required volunteer group size of future lip barrier studies for all test parameters, coefficients of variation (CV) were calculated and plots showing the required sample size for a given percentage treatment effect. RESULTS: Raman spectroscopy assessed parameters on the lower lip comprehensively characterized the state of the lip barrier. Parameter variability was sufficiently low to corroborate changes in most parameters using relatively small study populations. CONCLUSIONS: Lip skin is comparatively well hydrated. Biophysical measurement of the lip barrier function is a challenge, as unconscious licking of the lower lip has to be prevented. In vivo confocal Raman spectroscopy provides insightful parameters for the characterization of the lip barrier and sufficiently low inter-individual variability to assess relatively small parameter changes employing relatively few study subjects. Differences at the molecular level and at a high spatial resolution are detectable, and these insights might provide a breakthrough in the evaluation of lip barrier function and developing solutions for lip care.

Confocal Raman Spectroscopy as a tool to measure the prevention of skin penetration by a specifically designed topical medical device.

BACKGROUND/AIM: The scope of this study was to utilize confocal Raman spectroscopy in the evaluation of the degree of non-penetration into the viable skin layers of a paraffin and petrolatum-based product for use in the intimate areas of the skin. The formulation was purposely designed with properties to prevent undesirable skin penetration. METHODS: Product-The test product was a proprietary topical medical device comprising paraffinum liquidum, petrolatum, paraffin, and tocopheryl acetate. Volunteers-A total of 20 healthy volunteers were recruited onto the study-17 females and three males. Product Testing-Raman spectra were obtained at Baseline and 90 minutes after product application. Product Penetration-Skin penetration was calculated from Raman spectra taken at skin depths of -5, 0, 5, 10, 15, and 20 µm. RESULTS: Raman spectra of the investigated product could be clearly differentiated from the skin spectrum. The minimum measurable concentration of the test product was determined at a detection level of 0.5%. In this study, the test product did not penetrate down to skin depths of 10 to 20 µm. CONCLUSIONS: Within the precision range of the test method, the investigated product did not penetrate into the compact part of the stratum corneum. The study revealed Raman spectroscopy to be suitable to detect not only penetration but also non-penetration of substances into human skin.

Strategies for the identification of arginine ADP-ribosylation sites.

Mono-ADP-ribosylation of arginine is a protein modification in eukaryotic cells regulating protein activity and thereby influencing signal transduction and metabolism. Due to the complexity of the modification and the fragmentation pattern in MS/MS CID experiments, the identification of ADP-ribosylation sites in complex mixtures is difficult. Here we describe a two-step strategy, in the first step enriching and identifying potentially ADP-ribosylated proteins and in the second step identifying the sites of modification by a combination of LC/MS-, LC/MS(E) (MS at elevated fragmentation energy)- and LC/MS/MS experiments. Using this technique we could identify two ADP-ribosylation sites in TNFα digested with trypsin, protease V8 and both proteases and thereby demonstrate the specific ADP-ribosylation of TNFα. In complex samples the detection of ADP-ribosylated peptides requires further enrichment of the modified peptides. We tested various materials routinely used for the isolation of phosphopeptides. IMAC as well as TiO(2) chromatography were successfully applied for the selective enrichment of ADP-ribosylated model peptides.

ADP-ribosylation of arginine.

Arginine adenosine-5'-diphosphoribosylation (ADP-ribosylation) is an enzyme-catalyzed, potentially reversible posttranslational modification, in which the ADP-ribose moiety is transferred from NAD(+) to the guanidino moiety of arginine. At 540 Da, ADP-ribose has the size of approximately five amino acid residues. In contrast to arginine, which, at neutral pH, is positively charged, ADP-ribose carries two negatively charged phosphate moieties. Arginine ADP-ribosylation, thus, causes a notable change in size and chemical property at the ADP-ribosylation site of the target protein. Often, this causes steric interference of the interaction of the target protein with binding partners, e.g. toxin-catalyzed ADP-ribosylation of actin at R177 sterically blocks actin polymerization. In case of the nucleotide-gated P2X7 ion channel, ADP-ribosylation at R125 in the vicinity of the ligand-binding site causes channel gating. Arginine-specific ADP-ribosyltransferases (ARTs) carry a characteristic R-S-EXE motif that distinguishes these enzymes from structurally related enzymes which catalyze ADP-ribosylation of other amino acid side chains, DNA, or small molecules. Arginine-specific ADP-ribosylation can be inhibited by small molecule arginine analogues such as agmatine or meta-iodobenzylguanidine (MIBG), which themselves can serve as targets for arginine-specific ARTs. ADP-ribosylarginine specific hydrolases (ARHs) can restore target protein function by hydrolytic removal of the entire ADP-ribose moiety. In some cases, ADP-ribosylarginine is processed into secondary posttranslational modifications, e.g. phosphoribosylarginine or ornithine. This review summarizes current knowledge on arginine-specific ADP-ribosylation, focussing on the methods available for its detection, its biological consequences, and the enzymes responsible for this modification and its reversal, and discusses future perspectives for research in this field.