Article

Influence of vitamin E acetate on stratum corneum hydration

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Abstract

The influence of vitamin E (tocopherol, CAS 10191-41-0) on stratum corneum hydration was tested in O/W and W/O emulsions. Additionally, the O/W emulsion was used in an in vivo/in vitro method to gravimetrically obtain evidence concerning the water-binding capacity of the stratum corneum. In the W/O emulsion, 2.5%, 5%, and 7.5% vitamin E were compared. With both types of emulsions, vitamin E increased the stratum corneum hydration statistically significantly (p = 0.0002). In addition, we could provide evidence of an enhanced water-binding capacity after treatment with vitamin E (p = 0.05). For the hydrating effect of vitamin E. its concentration is of importance. The optimum concentration turned out to be 5%.

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... For vitamin E alone, hydro-alcoholic solution of alpha-tocopherol showed a reduction of UV-induced erythema in the epidermis [62] and the reduction on the number of epidermal sunburn cells. While O/W and W/O emulsions containing alpha-tocopherol acetate increased skin hydration and water-binding capacity in the stratum corneum [63]. Vitamin E is also used as coadjutant in other topical products to improve physical-chemical characteristics or to donate different effects. ...
... Thus, the topical use of vitamin E is adequate for its recognized antioxidant and protective activities, favoring the improvement of the skin barrier due to its lipophilic character and also, effectively avoiding lipid peroxidation by protecting cell membranes from the action of free radicals [103]. Gehring et al. [63] evaluated the hydration capacity of the stratum corneum by the use of vitamin E (5%) in water/ oil and oil/water emulsions, demonstrating moisturizing activity in the stratum corneum, in addition to providing indications that indicate retention of water in the stratum corneum. Gonullu and collaborators [104] also report that the topical use of vitamin E for a period of two to four weeks can improve the ability of water to retain in the skin, favoring hydration. ...
Chapter
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Vitamins are part of the antioxidant system of human skin, and are detectable in different layers, so the topical application can be an alternative to maintain the functionality of the system. The capacity of the antioxidant gradient of keratinocytes is associated with attenuation of the action of related free radicals in both esthetics and health. These problems arise from extrinsic aging and are related to the risk of cancer. Vitamin E has been proven to have antioxidant and moisturizing properties in the skin and can protect against the damage of UVB radiation, with emphasis on the reduction of acute erythema and photoaging. The choice for the use of topical vitamin E, compared to the oral is given by the safety as mild irritation and it has potential for multifunctional topical formulations. The purpose of the chapter is to review the topical use of formulations with vitamin E, addressing the development, safe use and evaluation of effectiveness.
... Tocopheryl acetate is a free radical scavenger that may reduce DNA damage and the rate of death in keratinocytes [6]. In addition, it can enhance stratum corneum hydration [7] and reduce skin roughness. ...
... These results are similar to the ones obtained by Darvin et al. [7] who observed that an optimal mixture of antioxidants protected the formulations against oxidation, extending their working life and the protection of the skin against the negative action of produced free radicals. Benevenuto et al. [27] also showed that formulations containing vitamin A palmitate with UV-filters combined with some photostabilizers had better protective effects on hairless mice skin than the ones without any photostabilizer. ...
Article
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Chemically stable ester derivatives of vitamins A, C and E have become a focus of interest for their role in the satisfactory results in skin aging treatments. Accordingly, the aim of this study was to evaluate the physical and chemical stability of a cosmetic formulation containing 1% retinyl palmitate, ascorbyl tetraisopalmitate and tocopheryl acetate, alone or in combination. In the studies of physical stability, a Brookfield rheometer was used to determine rheological behavior of formulations containing the vitamins. Chemical stability was determined by HPLC on a Shimadzu system with UV detection. Results showed that formulations had pseudoplastic behavior and that vitamins did not alter their apparent viscosity and thixotropy. In the chemical stability studies, first-order reaction equations were used for determinations of the shelf-life of vitamins derivatives considering a remaining concentration of 85%. Combined vitamins in a single formulation had a slightly lower degradation rate as compared to different preparations containing only one of the vitamins. Considering that many cosmetic formulations contain vitamin combinations it is suggested that the present study may contribute to the development of more stable formulations containing liposoluble vitamins.
... Excipients were selected on the basis of their characteristics and properties. It is well known that vitamin E has a crucial role in defending cell membranes by free radicals which cause degradation of lipids, and acts by inhibiting protein kinase C activity and mediating the collagenase expression [6,7]. In particular, esters of vitamin E are often used in topical products, because these are extremely stable and easily bio-converted to vitamin E. Hence, in this study, vitamin E acetate was selected as lipophilic phase [8]. ...
Article
Microemulsions are optically nanosized emulsions, isotropic and thermodynamically stable. They represent versatile drug delivery systems with high potential because can be administered through all routes. In the present study, we report on the formulation of a microemulsion made with glycerol (2.25%), Labrasol (20.25%) vitamin E acetate (2.50%), and water (75.00%), which was developed using the pseudo-ternary phase diagram. Globules of the microemulsion had PdI less than 0.25 and size of about 17 nm, evaluated by DLS analysis. These values did not change after loading khellin, a natural lipophilic molecules with interesting biological activities, used as a model of lipophilic drug. Carboxymethyl cellulose was selected as gelling polymer to obtain a microemulgel. Viscosity was 22,100.0±1555.6 mPas·s at 21±2°C, while it was 8,916.5±118.1 mPas·s at 35±2°C, remaining stable over time. Khellin recovery was 93.16±4.39% and it was unchanged after 4 weeks of storage (93.23±2.14%). The pH was 6.59±0.19 and it was found 6.42±0.34 at the end of the storage lifetime. The diffusion of khellin from the developed formulation was prolonged over an extended period. Based on overall results and due to the dermatological properties of the ingredients of the formulation, the developed microemulgel loaded with khellin is very promising and suitable for skin care applications.
... Retinyl palmitate has a beneficial effect on dry and rough skin epithelization and abnormal keratinization [125]. Vitamin C enhances skin hydration [126]. Tocopheryl acetate has a free radical scavenger activity, decreases DNA damage, keratinocyte death [127], skin roughness, and improves stratum corneum hydration [128]. ...
Article
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Nowadays, much attention is paid to issues such as ecology and sustainability. Many consumers choose "green cosmetics", which are environmentally friendly creams, makeup, and beauty products, hoping that they are not harmful to health and reduce pollution. Moreover, the repeated mini-lock downs during the COVID-19 pandemic have fueled the awareness that body beauty is linked to well-being, both external and internal. As a result, consumer preferences for makeup have declined, while those for skincare products have increased. Nutricosmetics, which combines the benefits derived from food supplementation with the advantages of cosmetic treatments to improve the beauty of our body, respond to the new market demands. Food chemistry and cosmetic chemistry come together to promote both inside and outside well-being. A nutricosmetic optimizes the intake of nutritional microelements to meet the needs of the skin and skin appendages, improving their conditions and delaying aging, thus helping to protect the skin from the aging action of environmental factors. Numerous studies in the literature show a significant correlation between the adequate intake of these supplements, improved skin quality (both aesthetic and histological), and the acceleration of wound-healing. This review revised the main foods and bioactive molecules used in nutricosmetic formulations, their cosmetic effects, and the analytical techniques that allow the dosage of the active ingredients in the food.
... vitamin E is the commonly used ingredient in many cosmetic as well as in pharmaceutical and nutraceutical preparations. In marketed Aloe-based pharmaceuticals and nutraceuticals many stabilizing and antioxidant agents such as vitamin E, vitamin C and vitamin A are commonly used in Aloe-based products(29). Thus, a parallel standard method for QA/QC purpose is needed to be established. ...
Article
Pharmacological activity of Aloe vera is known for hundreds of years, but a precise and well-established characterization method for all kinds of pharmaceutical formulations is still a challenging task. In the present study, a simple, user- friendly, sensitive, precise, accurate, robust and reproducible method has been developed based on reverse phase-high performance liquid chromatography (RP-HPLC). The RP-HPLC method has been developed, standardized and validated utilizing the Aloe marker compounds viz., Aloin A, Acemannan and Aloeemodin that is present in various Aloe vera varieties. The total polyphenolic content (TPC) and total flavonoid content (TFC) were estimated spectrophotometrically and an in-vitro antioxidant study was also performed to standardize the potential of Aloe vera using assays viz. DPPH (2,2- diphenyl-1-picrylhydrazyl radical scavenging), NO (nitric oxide) scavenging potential, FRAP (ferric reducing antioxidant power) and TAC (total antioxidant capacity). Simultaneously, tocopherol acetate was also estimated in commercially manufactured pharmaceutical products with the help of the previously standardized HPLC method in our laboratory. Separation of the singular active ingredient of Aloe vera was achieved by using an isocratic mode of acetonitrile and water (70:30 v/v) by using a reversed-phase C18 column as stationary phase in a high-performance liquidchromatography system employing photodiode array detector (PDA plus detector) with a flow rate of 1.0 ml/min. The detection limit of active compound of Aloe species was found to be in the range of 0.00020 to 0.00051 µgL-1 (20 µL injection of each for five times). The quantitative method of Aloe vera extracts standardized vis-à-vis both with peel (AL-P) and without peel (AL-WP) form gives robust, precise (% RSD 1.13-3.84) and accurate results. This method is suitable for the detection of major pharmacologically active compounds present in Aloe vera-based pharmaceuticals and nutraceuticals.
... Цех фасовки туалетного мыла вырабатывает продукцию за счет механической обработки высококачественного ядрового мыла (который состоит в основном из натриевых солей натуральных и синтетических жирных кислот) с добавлением красителей, ароматизирующих и отбеливающих веществ (или без них), пластификаторов, антиоксидантов и других компонентов, улучшающих потребительские и косметические свойства мыла, а также с добавлением антисептических и смягчающих средств (или без них) [8]. ...
Article
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In the course of the work, the technology of obtaining toilet soap with cosmetic properties was improved; samples of soap with the introduction of physiologically functional substances into the composition of the formulation components were experimentally obtained in order to preserve the initial physiologically active properties. The technological process of preparing the basic toilet soap periodically indirect method of neutral fats includes the following stages: caustic saponification of the fat set; grinding soap base; upholding of the soap base; draining the soap base; ennoblement of a soapy glue. Saponification of the main fat raw material is carried out in the soap boiler and can be produced both on the rest of the soap from the previous cooking, and using the pre-refined adhesive residue from the previous brews. Grinding of the soap base is carried out by hot water 80–90 ?, dry table salt or solution of caustic alkali, which are delivered in separate portions at boiling of the mass with a steaming steam, in an amount necessary for mass separation during grinding into the core (toilet base) and saponified adhesive. The sedimentation of the soap base is made after grinding is performed to separate the mass in the grinding process into the core (toilet base) and the sapwood glue. The temperature of the soap mass before settling must be at least 100 °C. The settling time is not less than 24 hours. The preparation of the core is carried out in a soap boiler. Prefabricated soap of toilet soap is heated to a boil with a hot steam. Then produce a high level of sapper adhesive with dry table salt, which is introduced in the amount necessary to separate the mass into a core and a flushing liquor. After each portion of the salt is injected, the soap mass is boiled for 15–20 minutes until completely dissolved and uniformly distributed in the mass. Salting is considered complete if the soap in the cauldron acquires a granular structure and in the sample on the spatula the kernels of the nucleus are clearly visible, between which the flaked lye flows.
... Vitamin E is recognized as the best antioxidant of biological membranes [35] and it reduces DNA damage and skin roughness [36]. The antioxidant diffuses the ROS into human tissue decelerating the extrinsic skin ageing [37]. ...
Article
Non-invasive in vivo human studies have always been of great importance owing to their advantages over the invasive studies. This research work also presents such a non-invasive study dealing with the penetration of two vitamin derivatives: retinyl acetate and alpha-tocopheryl acetate, into the stratum corneum of two groups of study participants categorized based on age as young (average age of 24.1 ± 3.3 years old) and elderly groups (average age of 68 ± 5.8 years old). According to the increase of age it is expected that intrinsic alterations may occur in the stratum corneum. Understanding these alterations is relevant to the knowledge of the differences between stratum corneum as a function of age-dependence thus, leading to the development of new specific products for ageing. The penetration of these derivatives was semi-quantitatively analyzed using confocal Raman spectroscopic technique with 3510 Skin Composition Analyzer (River Diagnostics, Rotterdam, The Netherlands) with a diode laser of 785 nm wavelength and 26 mW power. The analysis was done in the extended fingerprint region (1800 - 400 cm−1) for the stratum corneum region of the skin considering the depths from surface up to 24 μm. The results of this study clearly indicated that these two vitamin derivatives penetrated significantly into the stratum corneum of both study groups and their penetration was mainly affected by the composition of SC and their physico-chemical properties. The penetration profile of the alpha-tocopheryl acetate displays significant statistical difference (p < 0.05) between groups from surface up to 12 μm.
... O α-tocoferol em concentrações de 0,05%-2% foi usado como antioxidante em preparações tópicas. Em altas concentrações (2-10%) o α-tocoferol pareceu promover benefícios na hidratação do estrato córneo (IDSON, 1978;GEHRING et al., 1998). O α-tocoferol puro e em preparações de α-tocoferol concentradas (10-20%) irritaram a pele humana, e causaram dermatite de contato e outros tipos de reações de hipersensibilidade imunológica foram reportados. ...
Article
Orientadora : Mayumi Eliza Otsuka Sato Dissertaçăo (mestrado) - Universidade Federal do Paraná, Setor de Cięncias da Saúde, Programa de Pós-Graduaçăo em Cięncias Farmacęuticas. Defesa: Curitiba, 2006 Inclui bibliografia Área de concentraçăo: Insumos, medicamentos e correlatos
... Vitamin A palmitate acts on epithelization and on abnormal keratinization (MaiaCampos et al., 1999). Vitamin E acetate is a free radical scavenger and can reduce DNA damage and keratinocytes death (sunburn cell formation) (McVean and Liebler, 1997;Gaspar and Maia Campos, 2003) and also can enhance stratum corneum hydration and reduce skin roughness (Gehring et al., 1998). Tetra-isopalmitoyl ascorbic acid (VC-IP) releases vitamin C in physiological conditions and enhances cellular tolerance against UVB and reactive oxygen species as well as reduces the production of interleukin-1a and prostaglandin E2 (Ochiai et al., 2006). ...
Article
Saccharomyces cerevisiae extract (SCE) is used in cosmetics since it can act in oxidative stress and improve skin conditions. This study investigated dermatological effects of cosmetic formulations containing SCE and/or vitamins A, C and E. The formulation studied was supplemented or not (F1: vehicle) with vitamins A, C and E esters (F2) or with SCE (F3) or with the combination of vitamins and SCE (F4). Formulations were patch tested on back skin of volunteers. For efficacy studies, formulations were applied on volunteers and transepidermal water loss (TEWL), skin moisture (SM), skin microrelief (SMR) and free radicals protection were analysed after 3h, 15 and 30 days of application. Volunteers were also asked about efficacy perception. It was observed that F4 provoked a slight erythema in one volunteer. All formulations enhanced forearm SM. Only F3 and F4 presented long term effects on SMR and showed higher texture values; F3 had the highest brightness values. Our results suggest that vitamins and SCE showed effects in SM and SMR. Only formulations containing SC had long term effects in the improvement of SMR. Thus, these kinds of evaluations are very important in cosmetics development to evaluate the best risk and benefit correlation.
Chapter
Vit E is a collective term referring a group of 8 naturally occurring lipid-soluble molecules (homologs), of which 4 are tocopherols (α, β, γ, and δ tocopherols) and 4 are tocotrienols (α, β, γ and δ tocotrienols) [1]. Vit E was discovered in 1922 by Evans and Bishop, of the University of California in Berkeley, and the name “tocopherol” they proposed is derived from the Greek word “tocos” = offspring and the Greek verb “phero” = to bear, since the unknown till that time molecule was required to prevent fetal resorption in pregnant rats fed lard-containing diets that were easily oxidizable [2]. The -ol ending indicates its alcohol functional group. Tocopherol became known as the “antisterility vitamin”, but soon scientists realized that it had this effect only in rats.
Chapter
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The objective of this research was to investigate the effect of concentration and delivery system on skin permeation of alpha-tocopherol (alpha-T). Also, the addition of sunscreens and oleic acid on alpha-T permeation was studied using an in vitro micro-Yucatan pig skin model. Various delivery systems of alpha-T (1%) were formulated, which included simple solution, gels, emulsions, and microemulsions. The experimental design chosen for this study was a statistical randomized complete block design. alpha-T delivery was proportional to its concentration. The hydroalcoholic gel delivered significantly higher amounts of alpha-T into the receptor than the other gels used. A microemulsion containing isopropyl myristate emerged as the best delivery system for alpha-T among all the systems studied. Pig skin is a suitable in vitro model for studying the permeation of alpha-T and possibly other antioxidants, though in vivo experiments in humans are required to further corroborate the data.
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Wrinkles now have a greater social impact because people live longer. Science and hedonism overlap in the search for causes, treatments and prevention of wrinkles. The cosmetic approach to wrinkles includes: Active ingredients go well beyond simple moisturisers and exert a more complex activity in protecting skin from external injuries, nourishing it and removing its superficial layers. Transport systems and excipients are increasingly effective. Functional agents currently include alpha hydroxy acids (AHAs), poly-AHAs, complex poly-AHAs, retinoids, fish polysaccharides, anti-enzymatic agents, antioxidants (including ascorbic acid, pycnogenol, ursolic acid, vegetable isoflavones, vitamin E, coenzyme Q10, lipoic acid, resveratorol, l-carnosine and taurine) as well as agaricic acid and various plant extracts. All are reviewed in this text. Most are topical, some can be given by mouth, even as food supplements. Cosmetics are becoming closer to drugs in preventing and treating wrinkles. Included amongst the cosmeceuticals are the anti-wrinkle agents described herein.
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