ABSTRACT
Aim: To enhance the tretinoin (TRE) safety profile through the encapsulation in nanostructured lipid carriers (NLC). Materials & methods: NLC-TRE was developed using a 23 experimental factorial design, characterized (HPLC, dynamic light scattering, differential scanning calorimetry, x-ray diffraction analysis, transmission electron microscopy, cryo-transmission electron microscopy) and evaluated by in vitro studies and in healthy volunteers. Results: The NLC-TRE presented spherical structures, average particle size of 130 nm, zeta potential of 24 mV and encapsulation efficiency of 98%. The NLC-TRE protected TRE against oxidation (p < 0.0001) and promoted epidermal targeting (p < 0.0001) compared with the marketed product, both 0.05% TRE. The in vitro assay on reconstructed human epidermis and the measurement of transepidermal water loss in healthy volunteers demonstrated an enhanced safety profile in comparison to the marketed product (p < 0.0002). Conclusion: The NLC-TRE enhances the epidermal targeting and safety profile of TRE, representing a potential safer alternative for the topical treatment of skin disorders using TRE.
Subject(s)
Nanostructures , Tretinoin , Drug Carriers , Healthy Volunteers , Humans , Lipids , Particle SizeABSTRACT
BACKGROUND: The use of soap for skin cleansing is common among the population. However, it is possible that it causes damage to skin cells and disrupts the skin barrier. OBJECTIVE: To determine the cytotoxic effect of soaps on in vitro-cultured keratinocytes and to correlate it with clinical irritation. METHOD: A survey was conducted to find out the most widely used commercial soaps and their number. Subsequently, their cytotoxicity was evaluated in human keratinocyte cultures using the resazurin assay. The soaps with the highest and lowest cytotoxicity were applied to the skin of healthy volunteers to assess their effect on the skin barrier using colorimetry and transepidermal water loss (TEWL) assays. RESULTS: Of the analyzed soaps, 37 % were shown to be toxic to keratinocytes in vitro. The soap with the highest toxicity induced the highest rate of erythema and TEWL, in comparison with the least toxic soap and the vehicle used as the control solution. CONCLUSION: Soaps marketed for skin cleansing can contain chemical ingredients that damage human keratinocytes and cause skin barrier subclinical irritation. Their use can worsen preexisting dermatoses, generate xerotic or irritant contact dermatitis, and cause atrophy and dermatoporosis.
INTRODUCCIÓN: El jabón para el aseo cutáneo es de empleo común entre la población, sin embargo, es posible que cause daño a las células de la piel y modifique la barrera cutánea. OBJETIVO: Determinar el efecto citotóxico de los jabones en queratinocitos cultivados in vitro y correlacionarlo con la irritación clínica. MÉTODO: Se realizó una encuesta para conocer los jabones comerciales más utilizados y su cantidad; posteriormente, se evaluó su citotoxicidad en cultivos de queratinocitos humanos mediante el método de resazurina. Los jabones con mayor y menor citotoxicidad se aplicaron en piel de voluntarios sanos para evaluar su efecto en la barrera cutánea mediante ensayos de colorimetría y pérdida transepidérmica de agua. RESULTADOS: De los jabones analizados, 37 % demostró ser tóxico para los queratinocitos in vitro. El jabón con mayor toxicidad indujo el mayor índice de eritema y pérdida transepidérmica de agua, en comparación con el jabón menos tóxico y el vehículo empleado como solución control. CONCLUSIÓN: Los jabones comercializados para el aseo cutáneo pueden incluir ingredientes químicos que dañan los queratinocitos humanos y causan irritación subclínica de la barrera cutánea. Su utilización puede agravar dermatosis preexistentes, generar dermatitis xerósica o de contacto irritativa y causar atrofia y dermatoporosis.
Subject(s)
Irritants/adverse effects , Keratinocytes/drug effects , Skin Irritancy Tests , Soaps/adverse effects , Body Water , Cells, Cultured , Colorimetry , Dermatitis, Irritant/etiology , Erythema/chemically induced , Healthy Volunteers , Humans , Hydrogen-Ion Concentration , Skin/drug effects , Soaps/chemistryABSTRACT
Resumen Introducción: El jabón para el aseo cutáneo es de empleo común entre la población, sin embargo, es posible que cause daño a las células de la piel y modifique la barrera cutánea. Objetivo: Determinar el efecto citotóxico de los jabones en queratinocitos cultivados in vitro y correlacionarlo con la irritación clínica. Método: Se realizó una encuesta para conocer los jabones comerciales más utilizados y su cantidad; posteriormente, se evaluó su citotoxicidad en cultivos de queratinocitos humanos mediante el método de resazurina. Los jabones con mayor y menor citotoxicidad se aplicaron en piel de voluntarios sanos para evaluar su efecto en la barrera cutánea mediante ensayos de colorimetría y pérdida transepidérmica de agua. Resultados: De los jabones analizados, 37 % demostró ser tóxico para los queratinocitos in vitro. El jabón con mayor toxicidad indujo el mayor índice de eritema y pérdida transepidérmica de agua, en comparación con el jabón menos tóxico y el vehículo empleado como solución control. Conclusión: Los jabones comercializados para el aseo cutáneo pueden incluir ingredientes químicos que dañan los queratinocitos humanos y causan irritación subclínica de la barrera cutánea. Su utilización puede agravar dermatosis preexistentes, generar dermatitis xerósica o de contacto irritativa y causar atrofia y dermatoporosis.
Abstract Introduction: The use of soap for skin cleansing is common among the population. However, it is possible that it causes damage to skin cells and disrupts the skin barrier. Objective: To determine the cytotoxic effect of soaps on in vitro-cultured keratinocytes and to correlate it with clinical irritation. Method: A survey was conducted to find out the most widely used commercial soaps and their number. Subsequently, their cytotoxicity was evaluated in human keratinocyte cultures using the resazurin assay. The soaps with the highest and lowest cytotoxicity were applied to the skin of healthy volunteers to assess their effect on the skin barrier using colorimetry and transepidermal water loss (TEWL) assays. Results: Of the analyzed soaps, 37 % were shown to be toxic to keratinocytes in vitro. The soap with the highest toxicity induced the highest rate of erythema and TEWL, in comparison with the least toxic soap and the vehicle used as the control solution. Conclusion: Soaps marketed for skin cleansing can contain chemical ingredients that damage human keratinocytes and cause skin barrier subclinical irritation. Their use can worsen preexisting dermatoses, generate xerotic or irritant contact dermatitis, and cause atrophy and dermatoporosis.
Subject(s)
Humans , Soaps/adverse effects , Keratinocytes/drug effects , Skin Irritancy Tests , Irritants/adverse effects , Skin/drug effects , Soaps/chemistry , Body Water , Cells, Cultured , Dermatitis, Irritant/etiology , Colorimetry , Erythema/chemically induced , Healthy Volunteers , Hydrogen-Ion ConcentrationABSTRACT
BACKGROUND: Moisturizer is an important component of many cosmetic products. It helps to maintain the skin's integrity and its barrier functions. Recently, magnetic masks that seek to improve the properties of the skin have been developed and have become a new cosmetic trend. However, scientific proof of their stated properties is lacking. AIMS: To test whether iron oxide contained in a face mask with magnetic properties in an oily matrix with a freeze-dried aloe-vera base increases moisturization of the skin and improves skin barrier function. METHODS: Formulations were prepared containing an oil phase (67.3% wt.) and a solid phase (32.7% wt.). The moisturizing properties of the mask were tested by measuring in vivo electrochemical impedance spectroscopy, contact angle, and visual appearance. Meanwhile, human panel tests were performed to evaluate the sensory perception of potential users. RESULTS: The moisturizing effect of the iron oxide mask is clearly superior to that of the other tested samples. Water retention and low transepidermal water loss (TEWL) were evidenced for the iron oxide magnetic mask. Its occlusive action on the skin resulted in larger water contact angles and enhances the barrier effect. A favorable sensory perception on the part of the users was obtained for the iron oxide magnetic mask. CONCLUSION: The presence of iron oxide and the magnetic property of the mask enhance occlusive behavior, diminishing the TEWL. Sensory analysis of the iron oxide magnetic mask performed by human panel tests shows that they possess characteristics including neutral odor, and easy, pleasant-feeling application.
Subject(s)
Cosmetics/administration & dosage , Ferric Compounds/administration & dosage , Magnetic Phenomena , Skin Care/methods , Water Loss, Insensible/drug effects , Adult , Aloe/chemistry , Emollients/administration & dosage , Female , Humans , Male , Middle Aged , Plant Extracts/administration & dosage , Skin/drug effects , Skin/metabolismABSTRACT
The absorption modulating activity of two alkylglycerol derivatives (batyl and chimyl alcohol) on skin barrier properties was evaluated. Biophysical tests such as transepidermal water loss (TEWL) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, as well as in vitro skin permeation studies, were performed in order to determine the effect of these compounds as chemical absorption modulators. Four drugs were used as models: three NSAIDS (diclofenac, naproxen, and piroxicam) and glycyrrhizic acid. The results showed that treatment of the skin with alkylglycerols caused (i) a reduction on the amount of drug permeated; (ii) a reduction in TEWL; and (iii) changes in the ATR-FTIR peaks of stratum corneum lipids, indicative of a more ordered structure. All of these findings confirm that alkyl glycerols have an absorption retarding effect on the drugs tested. Such effects are expected to give rise to important applications in the pharmaceutical and cosmetic sectors, in cases where it is desirable for the drug to remain in the superficial layers of the skin to achieve a local effect.