Effects of 1,3-propanediol associated, or not, with butylene glycol and/or glycerol on skin hydration and skin barrier function.

OBJECTIVE: This study aimed to assess the effect of 1,3-propanediol at different concentrations (5%, 10%, or 15%), either applied alone or in combination with butylene glycol (BG) (5%) and/or glycerol (5%), on skin hydration and skin barrier function. The measurements were conducted using capacitance to determine skin hydration and trans epidermal water loss (TEWL) rates to evaluate skin barrier function. METHODS: A total of 30 healthy female subjects participated in the study. Capacitance and TEWL measurements were conducted at multiple time points, including before application and at 15 min, 2 and 8 h after the humectants were applied to the forearms of the subjects. All the subjects provided written informed consent. RESULTS: The 1,3-propanediol in all concentrations and in all combinations (with BG and/or glycerol) increased skin hydration and improved skin barrier function 15 min, 2 and 8 h after application. Glycerol increased the hydration performance of 1,3-propanediol. The application of 1,3-propanediol at a concentration of 15%, either alone or in combination with other humectants, reduced the TEWL to a greater extent than lower concentrations of 1,3-propanediol. Furthermore, the addition of glycerol to 1,3-propanediol 15% improved the skin barrier and reduced TEWL when compared with 1,3-propanediol alone and with the combination of 1,3-propanediol + BG. CONCLUSION: The humectants significantly improved skin hydration and reduced TEWL throughout the 8-h time course. The increase in 1,3-propanediol concentration, as well as its combination with glycerol, provided a greater benefit to the skin, improving both hydration and the skin barrier function.

OBJECTIF: Cette étude visait à évaluer l'effet sur l'hydratation de la peau et la fonction de barrière cutanée du 1,3-propanediol à différentes concentrations (5 %, 10 % ou 15 %), appliqué seul ou en association avec du butylène glycol (5 %) et/ou du glycérol (5 %). Les mesures ont été effectuées à l'aide de la capacitance pour déterminer l'hydratation de la peau et les taux de perte d'eau transépidermique (Trans Epidermal Water Loss, TEWL) pour évaluer la fonction de barrière cutanée. MÉTHODES: Au total, 30 sujets de sexe féminin en bonne santé ont participé à l'étude. Les mesures de la capacitance et de la TEWL ont été effectuées à plusieurs moments, y compris avant l'application, 15 minutes, 2 heures et 8 heures après l'application des produits humectant sur les avant-bras des sujets. Tous les sujets ont fourni un consentement éclairé écrit. RÉSULTATS: Le 1,3-propanediol, à toutes les concentrations et dans toutes les associations (avec le butylène glycol et/ou le glycérol), a augmenté l'hydratation de la peau et amélioré la fonction de barrière cutanée à 15 minutes, 2 heures et 8 heures après l'application. Le glycérol a augmenté les performances d'hydratation du 1,3-propanediol. L'application de 1,3-propanediol à une concentration de 15 %, seul ou en association avec d'autres produits humectant, a réduit la TEWL dans une plus grande mesure que des concentrations inférieures de 1,3-propanediol. En outre, l'ajout de glycérol au 1,3-propanediol 15 % a amélioré la barrière cutanée et réduit la TEWL par rapport au 1,3-propanediol seul et à l'association 1,3-propanediol + butylène glycol. CONCLUSION: Les produits humectant ont significativement amélioré l'hydratation de la peau et réduit la TEWL tout au long des 8 heures. L'augmentation de la concentration de 1,3-propanediol, ainsi que son association avec le glycérol, ont apporté un plus grand bénéfice à la peau, améliorant à la fois l'hydratation et la fonction de barrière cutanée.

Choline chloride-based deep eutectic solvent as an inhibitor of metalloproteases (collagenase and elastase) in cosmetic formulation.

Green chemistry and engineering are potential alternatives for achieving higher sustainability and lower generation of hazardous compounds in chemical product design, production, and use. Deep Eutectic Solvents (DES) are characterized as green solvents and have become increasingly attractive due to their characteristic design solvents. In this work, two DES (choline chloride (ChCl)/glycerol and ChCl/Urea), aqueous solutions of the DES-forming components, and green tea extracts obtained with DES were used as anti-ageing active in cosmetic products using in vitro tests to inhibit extracellular matrix metalloproteases (such as collagenase and elastase). Finally, the stability of the formulations with DES as a cosmetic active was also evaluated. The results showed that DES based on ChCl/Urea and ChCl/glycerol exhibited remarkable inhibition values of collagenase (91.1 and 92.7%, respectively) and elastase (49.8 and 45.7%, respectively). However, pure urea displayed better inhibition values (66%) for elastase, possibly due to its direct contribution to intramolecular hydrogen bonds. ChCl/glycerol showed remarkable stability in the average cube diameter values, which may indicate no change in the conformation of the micellar structure of the cosmetic formulation. Moreover, the formulation containing this DES remained stable at room temperature. Given the remarkable results, DES can be applied in cosmetic products for anti-ageing purposes.

Skin occlusive performance: Sustainable alternatives for petrolatum in skincare formulations.

BACKGROUND: The emollients are important ingredients used in skincare formulations that can act as moisturizing agents through their occlusive potential, preventing skin water loss. Consumer interest in natural and sustainable products has grown considerably in the last few years, requiring efforts from the cosmetic industry to design products with raw materials of natural, organic, and sustainable origin. Thus, it is essential to improve the knowledge about the behavior of cosmetic raw materials that can be used as sustainable alternatives to synthetic ingredients. AIM: This work aimed to evaluate the occlusive performance of different vegetable oils used as emollients in skincare cosmetics, through comparative analysis with petrolatum, a synthetic emollient with a high occlusive skin potential. METHOD: The study included 80 healthy female adult volunteers. TEWL measurements were performed before and after 15 min, 2 and 6 h of emollients application on the forearms of the research participants. All research participants provided written informed consent. RESULTS: The results obtained showed that the vegetable oils were effective in providing an occlusive effect on the skin. When compared to the petrolatum, the vegetable oils did not provide a high immediate skin occlusion effect. However, most of them showed a skin occlusion performance comparable to petrolatum throughout the 6 h time course. CONCLUSION: Vegetable oils can be used as a sustainable alternative to synthetic emollients, and they are promising in replacing petrolatum in skincare formulations with respect to the occlusion effect of the skin. The vegetable oils did not provide a high immediate skin occlusion effect (15 min post-application) as the petrolatum, which is known to have increased occlusion properties. However, most of them showed a skin occlusion performance comparable to petrolatum throughout the 6-hour time course.

High-frequency ultrasound as a scientific tool for skin imaging analysis.

Ultrasonic imaging is one of the most important diagnostic tools in clinical medicine due to its cost, availability and good correlation with pathological results. High-frequency ultrasound (HFUS) is a technique used in skin science that has been little explored, especially in comparison with other sites and imaging techniques. HFUS shows real-time images of the skin layers, appendages and skin lesions in vivo and can significantly contribute to advances in skin science. This review summarizes the potential applications of HFUS in dermatology and cosmetology, with a focus on quantitative tools that can be used to assess various skin conditions. Our findings showed that HFUS imaging is a reproducible and powerful tool for the diagnosis, clinical management and therapy monitoring of skin conditions. It is also a helpful tool for assessing the performance of dermatological products. This technique may eventually become essential for evaluating the performance of dermatological and cosmetic products.

Skin effect of facial cleansing combined with an electric sonic device.

BACKGROUND: New technologies, such as sonic devices, have been developed to optimize the skin cleansing process and improve its efficiency. To evaluate the effectiveness of these cosmetic procedures, skin bioengineering is an objective method to assess the biophysical parameters of the skin. AIMS: This study aimed to assess the effect of facial cleansing on the physiological properties of the skin by comparing a cleansing process with cosmetic product applied manually to cleansing with cosmetic product associated with the use of an electric sonic device. PATIENTS/METHODS: A gentle skin cleanser was applied to the entire face of 12 subjects; the sonic device was used on one half of the face and the manual process was performed on the other half. Instrumental skin analyses included sebummetry, corneometry, transepidermal water loss (TEWL), infrared thermography, and high-frequency ultrasound and were measured before and up to 90 min after cleansing. Results were compared using two-way ANOVA and Friedman tests. RESULTS: Data obtained from the statistical analysis of sebummetry, TEWL, thermography, and ultrasound parameters did not show any significant difference. When assessing the corneometry parameters, a significant reduction in hydration values (17.19%) was observed in the manual cleansing area, while the values remained similar to baseline values in the area where the sonic device was used. CONCLUSION: The cleansing process with a sonic device did not cause a significant hydration reduction, suggesting better preservation of skin homeostasis when compared to manual cleansing.

Development and cathodic iontophoretic permeation evaluation of liquid crystalline systems provided of retinoic acid microparticles.

BACKGROUND: The intracellular form of action of retinoids requires these agents to reach deeper layers of the skin with viable cells to ensure therapeutic efficiency. However, studies on swine skin models show that some retinoids have low skin permeability. Thus, the association of innovative formulations with technological strategies involving physical permeation promoters can be employed to increase the permeability of this active, ensuring a targeting effect of the active. AIMS: In this study, it was proposed the development and evaluation of the release and permeation profile of liquid crystalline systems with retinoic acid polymeric microparticles under passive or iontophoretic diffusional conditions. METHODS: For this study, release, permeation, and diffusional characterization assays were employed using the Franz diffusion cell model, associating or not the cathodic iontophoresis. RESULTS: Retinoic acid was considered stable in front of the electric current of 0.5mA/cm2 , because it did not show significant degradation (with maintenance from 96.03% to 98.57%), indicating the viability of such agents to be applied with iontophoresis. Controlled release profile was evidenced for microencapsulated systems. Comparatively, formulations F1, F3, and F5 presented a significantly higher RA release profile when compared to formulations with retinoic acid microencapsulated. A significant increase was observed in the absolute amount of RA retained in the skin with cathodic iontophoresis in all proposed formulations (P < .01). The increase was up to two times in relation to the passive condition. CONCLUSIONS: The combination of iontophoresis technique with application of retinoic acid and microencapsulated retinoic acid allows the penetration of the active ingredient to deeper layers of the skin.

Target action of antioxidants using iontophoresis.

BACKGROUND: The use of antioxidants in applications for topical use seems promising, however, many studies must be performed to ensure processes and products that can effectively bring benefits to combat the action of free radicals in the skin. For topical antioxidants to be effective against free radicals from the skin, it is essential that the antioxidants compounds permeate the different skin layers, to reach deeper layers of the epidermis in active form and stay there for a sufficient time to cause the beneficial effects. AIM: This work aimed to evaluate the antioxidant action of formulations with phenolic compounds as well as to comprehend the skin retention profile of these actives. METHODS: The antioxidant potential was recognized with isolated phenolic acids (gallic, caffeic, and ferulic acid) or in combinations, using different in vitro methods (DPPH ABTS , FRAP , ß-carotene/linoleic acid system and ORAC). The skin retention study was performed through in vitro assay with Franz's diffusion cell associating, or not, the cathodic iontophoresis. RESULTS: Gallic acid showed the greatest antioxidant activity and was selected for a study of skin permeation following gel application to porcine skin, with or without cathodic iontophoresis. Gallic acid retention in deeper skin layers was promoted by iontophoresis, and increased skin antioxidant activity was detected after only 20 min of iontophoresis. The present study demonstrated the importance of polymeric gelling agents for optimizing the antioxidant activity. CONCLUSION: The cathodic iontophoresis represents a promising strategy to promote a target action of antioxidants in the skin.

Gallic Acid-Loaded Gel Formulation Combats Skin Oxidative Stress: Development, Characterization and Ex Vivo Biological Assays.

Oxidative stress, which is a result of overproduction and accumulation of free radicals, is the main cause of several skin degenerative diseases, such as aging. Polyphenols, such as gallic acid, are an important class of naturally occurring antioxidants. They have emerged as strong antioxidants that can be used as active cosmetics. The purpose of this study was to develop a gallic acid-loaded cosmetic gel formulation and characterize it using rheological, mechanical, and bioadhesive tests. Its antioxidant effect in the stratum corneum was evaluated by a non-invasive method. According to the characterization tests, the formulation exhibited skin adhesiveness and pseudoplastic behavior without thixotropy, rendering it suitable for use as a cosmetic formulation. Furthermore, the non-invasive method indicated the antioxidant effect in the stratum corneum, with the global lipid peroxide reduction being 33.97 ± 11.66%. Thus, we were able to develop a promising gallic acid-loaded gel formulation that could reduce lipid peroxides and thus combat skin oxidative stress.