Topical dexpanthenol effects on physiological parameters of the stratum corneum by Confocal Raman Microspectroscopy.

BACKGROUND: Topical use of dexpanthenol presents well-established moisturizing properties and maintenance and repair of the skin barrier function, however, its exact action mechanisms are not completely elucidated. In this context, Confocal Raman Microspectroscopy is an optical method that enables non-invasive and non-destructive in vivo analysis with the sensitive acquisition of molecular changes in different skin layers. Herein, the aim was to evaluate the effects of topical dexpanthenol on the components and physiological parameters of the stratum corneum (SC). MATERIALS AND METHODS: Ten healthy female subjects underwent skin evaluation by means of a Confocal Raman Spectrometer Skin Analyzer 3510. Spectral data were obtained from the skin of the anterior forearm region, before and 2 h after applying a cosmetic formulation containing or not containing 5% dexpanthenol. RESULTS: Semiquantitative analysis of the natural moisturizing factor showed a significant decrease in content after 2 h of topical dexpanthenol application, while the analysis of the lamellar organization of intercellular lipids and the secondary structure of keratin showed a significant increase in hexagonal organization of lipids at the first half of the SC and a significant increase in ß-pleated sheet conformation of keratin. CONCLUSION: Effects of topical dexpanthenol on SC suggest a contribution in increasing fluidity of both lipidic and protein components of the SC and are compatible with dexpanthenol activity in maintaining adequate physiological conditions and preventing transepidermal water loss. This study also contributes to the elucidation of action mechanisms and other concurrent biochemical processes.

Prevention of chemically induced hair damage by means of treatment based on proteins and polysaccharides.

BACKGROUND: There is currently a great interest not only in developing products for the protection and recovery of chemically damaged hair, but also in developing effective protocols to investigate the impact of chemical treatments and attest the efficacy of innovative hair care products. Among the most relevant cosmetic treatments for hair are bleaching and coloring, which have been shown to significantly impair mechanical and structural properties. OBJECTIVES: This study aimed to characterize the damage induced by hair bleaching and coloring and to evaluate the protective effects of a hair care treatment based on integral silk proteins (fibroin and sericin) and vegetable-derived polysaccharides from linseed (Linum usitatissimum L.). METHODS: Hair swatches were subjected to different treatment protocols in order to evaluate the protective effect of proposed and benchmark products during bleaching and coloring processes. Tensile tests were performed to assess mechanical properties and improvement in resistance to breakage. Goniophotometric measurements were applied to determine improvement in luster. Hair fiber surface and relief were evaluated by SEM image analysis. RESULTS: Swatches bleached and treated with both evaluated products had a significant increase in resistance and reduced structural damage. Swatches colored and treated with both evaluated products showed reduced structural damage, and a significant increase in resistance and luster after the 1st and 5th washes. CONCLUSIONS: The proposed product was effective in protecting and repairing bleached and colored swatches, improving resistance and luster and reducing structural damage. By applying complementary techniques within a reliable evaluation protocol, it was possible to attest the protective properties of the product under study.