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Bioconversion of vitamin E acetate in EpiDerm skin. The EpiDerm skin was treated with an oil/water emulsion containing vitamin E acetate and incubated for 6 and 12 h. Treated and untreated samples (n>3) were extracted and analyzed as in figure 2. Each data point represents the mean×SD.
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Human studies have convincingly demonstrated pronounced photoprotective effects of 'natural' and synthetic antioxidants when applied topically before UVR exposure. Particularly with respect to UVB-induced skin damage such as erythema formation, the photoprotective effects of antioxidants are significant when applied in distinct mixtures in appropri...
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Essential oils are a mixture of volatile compounds, products of the secondary metabolism of plants. Once extracted, they can be deteriorated losing their organoleptic and therapeutic properties due to various environmental factors, being light exposure in aerobic conditions the main cause. In this work the oregano essential oil extraction and chara...
Citations
... By structure, AD is a naphthoic acid in which the phenolic hydroxy group has been converted to its methyl ether [22,47,48]. Additionally, AD has been used in combination with other drugs (e.g., topical antioxidants) to treat different skin disorders such as photoaging and depigmentation effects [49]. During the AD treatment, some local side effects can include erythema, dryness, peeling, burning, and itching [22,[47][48][49]. ...
... Additionally, AD has been used in combination with other drugs (e.g., topical antioxidants) to treat different skin disorders such as photoaging and depigmentation effects [49]. During the AD treatment, some local side effects can include erythema, dryness, peeling, burning, and itching [22,[47][48][49]. ...
... Melting points were 224.6 °C, 235.9 °C, 325.2 °C, and 328.4 °C for pure HC, CF, QR, and AD, respectively ( Figure 8). When the Tm peak of the pure compound ( Figure 8) does not appear in the thermogram of the nanoformulation or the physical mixture, the drug is converted from crystalline to amorphous phase, confirming its complete solubilisation into nanoparticle formulations [49]. All observed system endothermic peaks of BC pure compounds disappear during the scan until 400 °C (Figure 7b). ...
Biodegradable aliphatic polyester formulations as carriers for topical drug delivery show the potential to encapsulate structurally different therapeutic compounds. Poly(octamethylene suberate) (POS) nanoparticles (POS-NPs) were used as a matrix to encapsulate four therapeutic molecules used to treat skin disorders: caffeine (CF), quercetin (QR), hydrocortisone (HC), and adapalene (AD). Hydrophobicity and chemical structure of bioactive compounds (BCs) influenced the physicochemical stability of drug-loaded nanoparticles. The particle size of drug-loaded nanoparticles was between 254.9 nm for the CF-POS-NP and 1291.3 for QR-POS-NP. Particles had a negative charge from −27.6 mV (QR) to −49.2 mV (HC). Drug loading content for all BC-POS-NPs varies between 36.11 ± 1.48% (CF-POS-NP) and 66.66 ± 4.87% (AD-POS-NP), and their entrapment efficiency is relatively high (28.30 ± 1.81% and 99.95 ± 0.04%, respectively). Calorimetric analysis showed the appearance of polymorphism for AD- and HC-loaded systems and the drug’s complete solubilisation into all nanoparticle formulations. FTIR and NMR spectra showed apparent drug incorporation into the polymer matrix of NPs. The encapsulation of BCs enhanced the antioxidative effect. The prepared POS nanoparticles’ cytotoxicity was studied using two dermal cell lines, keratinocyte (HaCaT) cells and fibroblasts (HDFn). The nanoparticle cytotoxic effect was more substantial on HaCaT cell lines. A reconstructed human epidermis (RHE) was successfully used to investigate the penetration of polymeric NPs. Based on permeation and histology studies, HC-POS-NPs and CF-POS-NPs were shown not to be suitable for dermal applications with the explored drug concentrations. AD presents a high permeation rate and no toxic impact on RHE.
... The utilization of sunscreen encompassed photoprotective compounds is feasible to shield the skin from UVR [5][6][7][8]. At present, a mixture of organic filters (avobenzone and octinoxate) and inorganic filters (Zinc Oxide and Titanium Dioxide) are extensively available in commercial UV sunscreens [9]. ...
Excessive and prolonged ultraviolet radiation (UVR) exposure causes photodamage, photoaging, and photocarcinogenesis in human skin. Therefore, safe and effective sun protection is one of the most fundamental requirements. Living organisms tend to evolve various natural photoprotective mechanisms to avoid photodamage. Among them, melanin is the main functional component of the photoprotective system of human skin. Polydopamine (PDA) is synthesized as a mimic of natural melanin, however, its photoprotective efficiency and mechanism in protecting against skin damage and photoaging remain unclear. In this study, the novel sunscreen products based on melanin-inspired PDA nanoparticles (NPs) are rationally designed and prepared. We validate that PDA NPs sunscreen exhibits superior effects on photoprotection, which is achieved by the obstruction of epidermal hyperplasia, protection of the skin barrier, and resolution of inflammation. In addition, we find that PDA NPs are efficiently intake by keratinocytes, exhibiting robust ROS scavenging and DNA protection ability with minimal cytotoxicity. Intriguingly, PDA sunscreen has an influence on maintaining homeostasis of the dermis, displaying an anti-photoaging property. Taken together, the biocompatibility and full photoprotective properties of PDA sunscreen display superior performance to those of commercial sunscreen. This work provides new insights into the development of a melanin-mimicking material for sunscreens.
... Various types of environmental stressors affect our skin's health [1] [2] [3]. When exogenous interferences "sensed" stress, physiological response is triggered [1] [3] [4]. ...
... Natural compounds have been demonstrated to be safe and capable of protecting the skin from free radicals and photoaging [41,42,44,45] thanks to their polyphenolic composition, which is an index of the environmental stress the plant has gone through during the growth phase. Specifically, it has been demonstrated in humans that the topical application of natural antioxidants before exposure to UVA radiation reduces the photodermatoses induced by UVA light and increases the minimal dose to induce pigment darkening [44,46]. ...
... Natural compounds have been demonstrated to be safe and capable of protecting the skin from free radicals and photoaging [41,42,44,45] thanks to their polyphenolic composition, which is an index of the environmental stress the plant has gone through during the growth phase. Specifically, it has been demonstrated in humans that the topical application of natural antioxidants before exposure to UVA radiation reduces the photodermatoses induced by UVA light and increases the minimal dose to induce pigment darkening [44,46]. ...
Our body is continuously exposed to various exogenous aggressors, and, in particular, the skin represents the main target for outdoor stressors, including ultraviolet (UV) radiation. UV exposure is well-known to be associated with the development/worsening of extrinsic photoaging and a multitude of skin conditions. Considering the role of photoprotection in skin health, the research of natural photoprotective molecules becomes of great importance. Therefore, in this work we wanted to evaluate the beneficial protective effects of ripe berries of Vaccinium uliginosum (Alaska bog blueberry (BB)) extract (100 μg/mL) for preventing the cutaneous oxidative, inflammatory, and structural damage induced by exposure to 200 mJ of UVA/UVB radiation. We observed that the topical application of BB extract on human ex vivo skin explants averted the UV-induced cutaneous OxInflammatory phenomenon by quenching the increase in the oxidative and inflammatory marker levels, such as 4-hydroxynonenal (4HNE), heme-oxygenase-1 (HO-1), cyclooxygenase-2 (COX2), and aryl hydrocarbon receptor (AhR); as well as by counteracting the loss of structural proteins (filaggrin and involucrin) induced by UV radiation. Our data propose the use of a topical application of Alaska bog blueberry extract as a natural and valuable approach to ensure photoprotection against UV-induced skin damage and premature aging.
... Hydrophilic, lipophilic, and enzymatic antioxidants are present at higher concentrations in the epidermis than in the dermis layer of the skin [50]. In the epidermis, there is a concentration gradient of antioxidants [51,52]. The uppermost tissue layer, which is exposed to the environment, has the lowest concentration of antioxidants, and this concentration increases with the increasing depth of the epidermis. ...
... The uppermost tissue layer, which is exposed to the environment, has the lowest concentration of antioxidants, and this concentration increases with the increasing depth of the epidermis. Additionally, antioxidant levels can be enhanced by exogenous antioxidant treatments, such as vitamin C acetate and/or vitamin E [51,52]. ...
Abstract: Traumatic injuries to the nervous system, including the brain and spinal cord, lead to neurological dysfunction depending upon the severity of the injury. Due to the loss of motor (immobility) and sensory function (lack of sensation), spinal cord injury (SCI) and brain injury (TBI) patientsmay be bed-ridden and immobile for a very long-time. These conditions lead to secondary complications such as bladder/bowel dysfunction, the formation of pressure ulcers (PUs), bacterial infections, etc. PUs are chronic wounds that fail to heal or heal very slowly, may require multiple treatment modalities, and pose a risk to develop further complications, such as sepsis and amputation. This review discusses the role of oxidative stress and reactive oxygen species (ROS) in the formation of PUs in patients with TBI and SCI. Decades of research suggest that ROS may be key players in mediating the formation of PUs. ROS levels are increased due to the accumulation of activated macrophages and neutrophils. Excessive ROS production from these cells overwhelms intrinsic antioxidant mechanisms. While short-term and moderate increases in ROS regulate signal transduction of various bioactive molecules; long-term and excessively elevated ROS can cause secondary tissue damage and further debilitating complications. This review discusses the role of ROS in PU development after SCI and TBI. We also review the completed and ongoing clinical trials in the management of PUs after SCI and TBI using different technologies and treatments, including antioxidants.
... Due to the accumulation of carotenoids in the epidermis, in the cases of excessive carotenoid intake, mostly β-carotene, carotenoderma occurs as yellowish discoloration of the skin being most obvious on the palms and soles [52,53]. Besides the oral route of carotenoid administration, topical application is just as important, being especially of great interest for cosmetic companies [54][55][56][57][58]. Topical application of antioxidant (AO) substances such as carotenoids is closely related to skin protection from environmental factors and anti-aging [59,60]. ...
Due to their potential health-promoting effects, carotenoids have drawn both scientific and public attention in recent years. The primary source of carotenoids in the human skin is diet, mainly fruits, vegetables, and marine product, but they may originate from supplementation and topical application, too. In the skin, they accumulate mostly in the epidermis and act as a protective barrier to various environmental influences. Namely, the skin is exposed to numerous environmental factors, including ultraviolet radiation (UVR), air pollution, and smoking, that cause oxidative stress within the skin with consequent premature (extrinsic) aging. UVR, as the most prominent environmental factor, may cause additional detrimental skin effects, such as sunburn, DNA damage, and skin cancer. Therefore, photoprotection is the first line intervention in the prevention of premature aging and skin cancer. Numerous studies have demonstrated that carotenoids, particularly β-carotene, lycopene, lutein, and astaxanthin, have photoprotective effects, not only through direct light-absorbing properties, but also through their antioxidant effects (scavenging reactive oxygen species), as well as by regulation of UV light-induced gene expression, modulation of stress-dependent signaling, and/or suppression of cellular and tissue responses like inflammation. Interventional studies in humans with carotenoid-rich diet have shown its photoprotective effects on the skin (mostly by decreasing the sensitivity to UVR-induced erythema) and its beneficial effects in prevention and improvement of skin aging (improved skin elasticity and hydration, skin texture, wrinkles, and age spots). Furthermore, carotenoids may be helpful in the prevention and treatment of some photodermatoses, including erythropoietic protoporphyria (EPP), porphyria cutanea tarda (PCT) and polymorphous light eruption (PMLE). Although UVR is recognized as the main etiopathogenetic factor in the development of non-melanoma skin cancer (NMSC) and melanoma, and the photoprotective effects of carotenoids are certain, available studies still could not undoubtedly confirm the protective role of carotenoids in skin photocarcinogenesis.
... Direct evidence for the UV radiation-mediated generation of reactive species in skin is growing [9,10] which constitutes a rationale for the use of antioxidants in topical formulations, including anti-aging cosmetics [11,12]. The use of antioxidants in skin care is further supported by the reported efficacy in the enrichment of the endogenous cutaneous protection system after topical administration [13,14]. Herein, a study to identify antioxidant composition along a seven year period was performed in order to gather information on the most commonly used antioxidants in antiaging cosmetics. ...
Objective:
Skin health and beauty are a cornerstone of general well-being in humans. Anti-ageing cosmetics are used to provide a healthy and youthful appearance. Among the different cosmetic actives, antioxidants are incorporated in anti-ageing products due to their beneficial effects in preventing and minimizing the signs of skin ageing. This work aims to understand how anti-ageing formulations changed in the past 7 years regarding pure antioxidants composition.
Methods:
Data were collected from anti-ageing formulations commercialized in main stores and pharmacies in the Portuguese market. The study started on 2011 and was updated with products launched or whose composition has been renewed on 2013, 2015 or 2018.
Results:
Ascorbic acid and tocopherol and their derivatives were consistently the most used antioxidants in anti-ageing formulations; followed by niacinamide and retinyl palmitate. Seven ascorbic acid derivatives are currently used in anti-ageing formulations while only three tocopherol derivatives were identified in this study. Several combinations of antioxidants were routinely found, mainly tocopherol (or tocopherol derivatives) with other antioxidants and tocopherol with tocopherol derivatives. We have not identified emerging antioxidants with great impact in anti-ageing formulations even though niacinamide and retinyl palmitate exhibited over 10% more usage in 2018.
Conclusion:
This insight is relevant to the cosmetic industry providing a better understanding of the scientific-based formulation of modern cosmetics and supports the need for innovative antioxidants in anti-ageing cosmetics.
... Topical application of Vitamin C has demonstrated to be photo protective and prevent some of the actinic damage [24][25][26]. By preventing the absorption of ultraviolet radiation (both UVA and UVB, which trigger melanogenesis) also induces skin brightening [27]. In addition, this vitamin is necessary for the synthesis of another antioxidant vitamin, i.e., Vitamin E. Furthermore, Vitamin C is able to improve wrinkling and atrophy of the aged skin [28,29] due to its capacity to suppress Matrix-Metalloproteinases (MMPs), responsible for collagen degradation, increase the Tissue Inhibitor of MMPs (TIMPs) and the levels of collagens I and III [30,31]. ...
... The regular application of skin care products containing antioxidants may be of the utmost benefit in efficiently protecting the skin against exogenous oxidative stressors such as UV radiation or other chemicals occurring during daily life (Dreher and Maibach, 2001). The addition of naturally occurring compounds has been often considered in topical products (Chen et al., 2013;Goyal et al., 2015) due to fewer complications in terms of toxicity and high efficacy. ...
Although various compounds from Ilex paraguariensis present high antioxidant activity, limitations in terms of chemical stability may be found, impacting on the formulation step. In this context, nanotechnology may be alternatively used to provide an additional protection for these compounds, avoiding degradative reactions. Different formulation parameters (eg. particle size, zeta potential, internal phase fraction) were assayed to maximize a local antioxidant action. Firstly, the extraction procedure for obtaining increased concentrations of antioxidant compounds was optimized. High stirring speed and ethanol as extractor liquid were defined as key parameters. Nanoparticles were prepared by double emulsion solvent evaporation technique. Polycaprolactone-based nanoparticles showed to be more stable than poly(lactic-co-glycolic acid)-based nanoparticles. Instead of poly(vinyl alcohol), Pluronic® was selected as surfactant because it avoids aggregate formation and provides smaller particle size. While higher polymer content contributes positively to maintaining both reduced size particle and distribution, an increased extract concentration impacted negatively on these parameters. Stability studies were also performed using skin extracts and homogenates and confirmed that nanostructures provide an additional protection. Moreover, the incorporation of Ilex extract in nanoparticles significantly reduced the amount of chlorogenic acid permeated through the skin (no ex vivo permeation until 12 h for this system), extending its topical antioxidant effect.
... In oily skin, free radicals are related to inflammatory processes involved in the formation of acne lesions. Thus, the antioxidant activity of CAE can prevent and reduce acne lesions (24). In addition to antioxidant activity, CAE improved the sensory profile of the developed sunscreen formulation. ...
... Na pele oleosa, os radicais livres estão relacionados com processos inflamatórios envolvidos na formação de lesões de acne. Esta atividade antioxidante CAE pode prevenir e reduzir as lesões de acne (24) . Além da actividade antioxidante, CAE melhorou o perfil sensorial da formulação de protetor solar desenvolvida. ...
