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Antiaging effects of a novel facial serum containing L-Ascorbic acid, proteoglycans, and proteoglycan-stimulating tripeptide: ex vivo skin explant studies and in vivo clinical studies in women
Abstract and Figures
Background
With age, decreasing dermal levels of proteoglycans, collagen, and elastin lead to the appearance of aged skin. Oxidation, largely driven by environmental factors, plays a central role.
Aim
The aim of this study was to assess the antiaging efficacy of a topical serum containing L-Ascorbic acid, soluble proteoglycans, low molecular weight hyaluronic acid, and a tripeptide in ex vivo and in vivo clinical studies.
Methods
Photoaging and photo-oxidative damage were induced in human skin explants by artificial solar radiation. Markers of oxidative stress – reactive oxygen species (ROS), total glutathione (GSH), and cyclobutane pyrimidine dimers (CPDs) – were measured in serum-treated explants and untreated controls. Chronological aging was simulated using hydrocortisone. In both ex vivo studies, collagen, elastin, and proteoglycans were determined as measures of dermal matrix degradation. In women aged 21–67 years, hydration was measured up to 24 hours after a single application of serum, using Corneometer and hygrometer. Subjects’ perceptions of efficacy and acceptability were assessed via questionnaire after once-daily serum application for 4 weeks. Studies were performed under the supervision of a dermatologist.
Results
In the photoaging study, irradiation induced changes in ROS, CPD, GSH, collagen, and elastin levels; these changes were reversed by topical serum application. The serum also protected against hydrocortisone-induced reduction in collagen, elastin, and proteoglycan levels, which were significantly higher in the serum-treated group vs untreated hydrocortisone-control explants. In clinical studies, serum application significantly increased skin moisture for 6 hours. Healthy volunteers perceived the product as efficient in making the skin brighter, more hydrated, and decreasing wrinkles and wished to continue using it. The serum was well tolerated and noncomedogenic.
Conclusion
The serum protected against oxidative damage and dermal protein loss caused by photo- and chronological aging in human skin explants. In-vivo, the serum hydrated skin for 6 hours, and users perceived increased skin brightness, hydration, and fewer wrinkles.
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... The pharmaceutical serum or pharmaceutical-based cosmetic serum is relatively a new dosage form that has been developed and widely used in many cosmetic non-invasive procedures. The high skin penetration (epidermis to the dermis) of serum has been found to produce quick and tremendous effects on the skin [17,18,[22][23][24][25]. There are mainly seven types of topical serums that are used for different skin diseases and cosmetic purposes (Fig. 2). ...
... Many dermatologists and cosmetologists are prescribing serums to reverse several skin issues with a minimum duration of time. Different environmental conditions may bring about changes in the appearance of facial skin leading to poor texture, appearance of wrinkles, acne, rosacea, UV-induced dark spots, dryness, pigmentation issues (hypopigmentation and hyperpigmentation), and dullness of skin [23,[26][27][28][29][30][31][32][33]. Since facial serums are highly concentrated and are lighter in weight, they are formulated to deliver a higher amount of active ingredient(s) more quickly and efficiently [17,22,25,34]. ...
... It has been confirmed that the 56 days of post-application of the hyaluronic acid (HA) serum after the single-use of neuromodulator injection significantly reduced the sign of aging [128]. Additionally, L-ascorbic acid, ergothioneine, HA, and fragmented soluble proteoglycan peptides containing facial serum provide maximum protection against the photo-aged skin, minimizes the size of wrinkles, and increases skin hydration within 4 weeks of therapy [23]. However, some clinical data have proved that the application of facial night serum containing ascorbyl tetraisopalmitate, melatonin, and bakuchiol at bedtime plays an important role in skin tightening without any cause of irritation [48,49]. ...
The growth and demand for cosmeceuticals (cosmetic products that have medicinal or drug-like benefits) have been enhanced for the last few decades. Lately, the newly invented dosage form, i.e., the pharmaceutical-based cosmetic serum has been developed and widely employed in various non-invasive cosmetic procedures. Many pharmaceutical-based cosmetic serums contain natural active components that claim to have a medical or drug-like effect on the skin, hair, and nails, including anti-aging, anti-wrinkle, anti-acne, hydrating, moisturizing, repairing, brightening and lightening skin, anti-hair fall, anti-fungal, and nail growth effect, etc. In comparison with other pharmaceutical-related cosmetic products (creams, gels, foams, and lotions, etc.), pharmaceutical-based cosmetic serums produce more rapid and incredible effects on the skin. This chapter provides detailed knowledge about the different marketed pharmaceutical-based cosmetic serums and their several types such as facial serums, hair serums, nail serums, under the eye serum, lip serum, hand, and foot serum, respectively. Moreover, some valuable procedures have also been discussed which provide prolong effects with desired results in the minimum duration of time after the few sessions of the serum treatment.
... In an ex vivo experiment using abdominal skin samples obtained from healthy women, topical application (2 mg cm −2 ) of a serum containing AA, ergothioneine, a proteoglycanstimulating peptide (tetradecyl aminobutyroyl valylaminobutyric urea trifluoroacetate), soluble proteoglycans, and low molecular weight hyaluronic acid for 10 days significantly prevented the decreases in the levels of collagen, elastin, and proteoglycan induced by daily irradiation with UV/visible/infrared rays (10 J cm −2 ) or by daily treatment with hydrocortisone (10 µg mL −1 ) [74]. ...
... The antioxidant effect of AA will be enhanced when it is combined with other antioxidants with different redox potentials, such as α-tocopherol [121,122]. The combination of AA with other vitamins, natural products, or peptides with different mechanisms of action synergistically protects cells from photooxidative stress [123], enhances collagen synthesis [72][73][74], and retards skin aging [71,[75][76][77]. Since GSH and NADPH are used as electron donors for the enzymatic regeneration of AA, the biological effects of AA could be enhanced by combining AA with thiol compounds and nicotinamide. ...
Ascorbic acid (AA) is an essential nutrient and has great potential as a cosmeceutical that protects the health and beauty of the skin. AA is expected to attenuate photoaging and the natural aging of the skin by reducing oxidative stress caused by external and internal factors and by promoting collagen gene expression and maturation. In this review, the biochemical basis of AA associated with collagen metabolism and clinical evidence of AA in increasing dermal collagen and inhibiting skin aging were discussed. In addition, we reviewed emerging strategies that have been developed to overcome the shortcomings of AA as a cosmeceutical and achieve maximum efficacy. Because extracellular matrix proteins, such as collagen, have unique amino acid compositions, their production in cells is influenced by the availability of specific amino acids. For example, glycine residues occupy 1/3 of amino acid residues in collagen protein, and the supply of glycine can be a limiting factor for collagen synthesis. Experiments showed that glycinamide was the most effective among the various amino acids and amidated amino acids in stimulating collagen production in human dermal fibroblasts. Thus, it is possible to synergistically improve collagen synthesis by combining AA analogs and amino acid analogs that act at different stages of the collagen production process. This combination therapy would be useful for skin antiaging that requires enhanced collagen production.
... Skin aging results in a thinner and less well-protected skin. 13,14 It is caused by a combination of genetic factors and exposome factors (environmental and biological factors) on top of chronological aging. 15 Due to modern urban life, the population is exposed on a daily basis to solar radiation and other external factors including air pollution, tobacco smoke, stress, or solar radiation. ...
... 16 Oxidative stress has been described as the most important biological consequence of these exposome factors, resulting in the formation of RMS (ROS, RNS, and RCS), which can play a major role in the alteration of the homeostasis of the skin and premature aging by degradation of components of the ECM and reduction in antioxidant capabilities in the skin. 13,17 Antioxidants can provide protection against this release of radicals and are becoming more widely used, in the form of vitamins or plant extracts, in cosmetic formulations. 8,15,17 Vitamin C is the most abundant antioxidant, that can interact with harmful free radicals and donate its electron. ...
Objective:
To assess the in vitro efficacy on antioxidant potential, protection against global oxidative stress, and effect on collagen neosynthesis of minimalist formula (Peptide-C ampoules product) containing 10% natural vitamin C, rice and lupin bio-peptides, hyaluronic acid, and Vichy volcanic mineralizing water (active mix).
Methods:
In-tube quantitative tests ("in-tube screening") assessed global antioxidant properties, anti-lipid peroxidation, anti-protein glycosylation, and metalloproteinase inhibition (anti-collagenase, anti-elastase, and anti-hyaluronidase activity) properties of the formula. Protection against oxidative stress was evaluated on human keratinocyte monolayer cultures, and collagen neosynthesis was quantified on fibroblast monolayer cultures treated with supernatants from product-treated reconstructed human epidermis.
Results:
Product (5% concentration) showed high antioxidant ability (blocking 99.0% oxidation), protection against oxidative stress damage (51.8% lipid peroxidation and 37.8% protein glycosylation decreases), and inhibition of hyaluronidase (21.9%), elastase (47.1%), and collagenase (61.8%). The protective effect was validated on human keratinocyte monolayer cultures in the presence of active mix (0.025%). Oxidative stress (ROS) was reduced by 99.0%, while global oxidative stress (RMS) induced by pollution, UVA radiation, and a combination of both factors was reduced by 48.94%, 8.7%, and 96.28%, respectively. The product increased collagen neosynthesis (11.21%) by cellular dialogue in fibroblasts incubated with product/mix-treated-RHE supernatants.
Conclusion:
The combination of ingredients in the product showed high global antioxidant capacity, as well as a protective effect against oxidative stress induced by UVA, pollution, or both combined factors and an ability to stimulate collagen neosynthesis in in vitro studies, which support the clinical efficacy of this product.
... There are several approaches that can be used to try to improve skin appearance of these body areas, and noninvasive methods (e.g., fillers and/or skin-boosters) are undoubtedly very popular, mainly because they allow an almost immediate return to daily and work activities by quickly restoring a fresh, and youthful appearance [6][7][8][9][10][11][12]. Whereas in the past cosmetic treatments were predominantly for the senior age and upper social classes, current users of aesthetic medicine are increasingly younger, better informed, and socially and economically diversified. ...
Objective: To assess the efficacy and tolerability of a hyaluronic acid (HA)-based injectable formulation of stable hybrid cooperative complexes of high (H-HA) and low (L-HA) molecular weight HA (32 mg of H-HA and 32 mg of L-HA) produced by NAHYCO® Hybrid Technology (Profhilo®, hereinafter referred to as "The product"), for the treatment of wrinkles, roughness and laxity of the skin of the face and neck areas in women of Chinese ethnicity resident in Italy. Methods: 28 women from 30 to 60 years of age were enrolled, 18 for the neck area and 10 for the face. The self-isolation of the included subjects due to the COVID-19 pandemic outbreak prevented the completion of the trial as to the approved protocol, which scheduled a follow-up until week 16 after baseline, and amendments to original plan were necessary. The product was intradermally injected in 2 sessions, 4 weeks apart, assessments were performed at 4, and 8 weeks after the first injection as to the neck, while 3 subjects were evaluated until week 12 for the face. Wrinkle Severity Rating Scale (WSRS), Facial Volume Loss Score (FVLS) were used to clinically assess results for the face, while the IBSA Neck Laxity Scale was used for neck evaluation; superficial and deep hydration were assessed by a corneometer and a moisturemeter while skin color changes of the face were measured with a spectrophotometer; all these evaluations were supported by 3D photographic documentation. Results: Data showed overall improvement of the evaluated parameters already after the first round of treatment both at the facial and neck level, with a benefit that was kept or increased after the second session, with a very high tolerability profile. Although the amelioration trend was clearly visible, the obtained data are not statistically significant, probably due to the COVID-19 pandemic outbreak that prevented to analyze results from a larger population. Conclusions: Despite further analysis are required, the product injections could represent a promising treatment to induce skin amelioration in both face and neck areas in Chinese women, and it was well-tolerated.
... Topical application of vitamin C increases levels of tissue inhibitors of collagen-degrading matrix metalloproteinase 1 (MMP-1) [126]. Garre et al. [127] reported that the application of a cosmetic formulation containing ascorbic acid to skin sections in vitro protected against oxidative damage and photoaging-induced protein loss. In tests on study participants, it provided very good skin hydration, and brightened and smoothed the skin [128]. ...
The subject of the work concerns the dermatological management of patients mainly with aged skin. The purpose of the work was to present the basic techniques and preparations which are performed by dermatologists in the treatment of aged skin. There are dermatological treatments related to the treatment of skin diseases and cosmetic treatments which are mainly related to skin care. In this work, the method of literature research was applied. On the basis of books and journal articles on dermatological and cosmetic procedures for aged skin, an analysis of treatment types was made. Then, the results of this analysis were presented in the paper under discussion. The paper presents information on the skin and its properties. The structure and functions of the skin, aging processes and characteristics of aged skin were discussed. Then, the possibilities of reducing the visible signs of skin aging through the use of invasive and non-invasive dermatological and cosmetological treatments were given, and the most important components of preparations used supportively in combating skin aging processes were discussed.
... 2,3 Pharmacological and pathological research have shown that the typical appearance of UV-induced SP originates from the degradation of extracellular matrix in the skin mediated by elevated expression of matrix metalloproteinases (MMPs), which is mainly achieved through signaling mediated by reactive oxygen species (ROS). 4 Repeated exposure of skin to UV produces excessive ROS (mainly O 2 − , H 2 O 2 and HO 2 − , and OH − ) through interactions with chromophoric groups such as intracellular melanin, uridylic acid, and nucleic acid; these events impair mitochondria function, causing them to produce more ROS during energy metabolism. 5,6 Excessive ROS activates numerous membrane receptors that further influence a series of signal transduction pathways, including nuclear transcription factor-κB (NF-κB) that is a central signaling pathway related to cell apoptosis, inflammatory response, and immune response in the SP process ( Figure 1). ...
Background:
Photoaging decreases quality of life and increases the risk of skin cancer, underscoring the urgent need to explore natural, high-efficacy, anti-skin photoaging (SP) active substances.
Methods:
In this study, a gel (CS/CSCPs/β-GP gel) was prepared using chitosan (CS) and sodium β-glycerophosphate (β-GP) through crosslinking with small molecular CSCPs as the carried drug. We evaluated its structural characteristics and properties. The effect of CS/CSCPs/β-GP gel on the degree of ultraviolet (UV)-induced skin aging of mice was investigated through comparative analysis of skin damage, the integrity of collagen tissues and elastic fibers, levels of reactive oxygen species (ROS) and key inflammatory factors (tumor necrosis factor [TNF]-α and interleukin [IL]-1β, IL-6, and IL-10), and tissue expression of matrix metalloproteinase-3 (MMP-3) after repeated UV irradiation in a nude mice SP model.
Results:
The results showed that CS/CSCPs/β-GP gel was successfully prepared and had the desired characteristics. Compared with CSCPs alone, the CS/CSCPs/β-GP gel more evidently improved typical photoaging characteristics on mouse dorsal skin. It also increased the moisture content, causing the skin to become glossy and elastic. Pathological skin analysis revealed that this peptide-carrying gel can effectively inhibit epidermal thickening, reduce tissue inflammatory infiltration, suppress collagen fiber degradation, increase the collagen content, alleviate structural elastic fiber damage, and significantly inhibit abnormal MMP-3 expression. In addition, biochemical analysis showed that the CS/CSCPs/β-GP gel can effectively inhibit the elevated expressions of ROS and key proinflammatory factors (TNF-α, IL-1β, IL-6) in photoaging skin tissues and promote expression of the anti-inflammatory factor IL-10.
Conclusion:
SP can cause many clinical skin diseases, such as solar freckle-like nevus, solar keratosis, cutaneous melanoma, and squamous cell carcinoma. CSCPs are a high-efficacy anti-SP natural active substance and CS/CSCPs/β-GP gel can synergistically enhance the CSCPs' anti-SP effect. The mechanism is likely related to the inhibited activation of ROS/nuclear transcription factor-κB signaling and the expression of downstream inflammatory factors.
... Similar results were also observed for immunofluorescence analysis (Fig. 5C). Disruption of the antioxidant-oxidant balance in an organism can lead to oxidative stress, and UV-driven oxidative stress plays a vital role in photoaging [46]. Changes in the levels of endogenous antioxidant enzymes (including CAT and SOD) and lipid peroxidation derivatives (MDA) can be used as indicators of oxidative damage [17]. ...
Cathelicidins are diverse effector molecules in the vertebrate immune system and are related to immune regulation, inflammatory response, wound healing, and blood vessel formation. However, little is known about their free radical scavenging ability, especially in vivo. In this study, a cathelicidin molecule (cathelicidin-NV, ARGKKECKDDRCRLLMKRGSFSYV) previously identified from the spot-bellied plateau frog (Nanorana ventripunctata) (Anura, Dicroglossidae, Dicroglossinae) by us was shown to alleviate ultraviolet B (UVB)-induced skin photoaging in mice. Cathelicidin-NV effectively suppressed cytotoxicity, DNA fragmentation, apoptosis and reduced the protein expression levels of JNK, c-Jun, and MMP-1, which are involved in the regulation of collagen degradation in HaCaT cells induced by UVB irradiation. Furthermore, cathelicidin-NV also scavenged UVB-induced intracellular reactive oxygen species (ROS). Taken together, cathelicidin-NV directly scavenged excessive intracellular ROS to protect HaCaT cells, and subsequently alleviated UVB-induced skin photoaging. This study extends reports on the antioxidant function of the cathelicidin family. In addition, the properties of cathelicidin-NV make it an excellent candidate for the prevention and treatment of UV-induced skin photoaging.
... HA is one of the known GAGs that form proteoglycan aggregates, which crosslink with other matrix proteins such as collagen, constituting supermolecular structures that increase skin firmness [13]. Previous studies on proteoglycans, HA, and collagen have focused on their anti-aging and anti-wrinkle effects [13][14][15][16][17][18][19][20]. ...
Dry and eczema-prone skin conditions such as atopic dermatitis and xerotic eczema primarily indicate an impaired skin barrier function, which leads to chronic pruritus. Here, we investigated the effects of a novel emollient containing H.ECMTM liposome, which contains a soluble proteoglycan in combination with hydrolyzed collagen and hyaluronic acid. A prospective, single-arm study was conducted on 25 participants with mild atopic dermatitis or dry skin to assess the hydration and anti-inflammatory effect of the novel emollient applied daily over four weeks. All efficacy parameters, including itching severity, transepidermal water loss, and skin hydration, improved significantly after four weeks. The in vitro and ex vivo studies confirmed the restoration of the skin’s barrier function. The study revealed the clinical and laboratory efficacy of H.ECMTM liposome in reducing itching and improving the skin’s barrier integrity. Thus, the use of H.ECMTM liposome can be considered a therapeutic option for dry and eczema-prone skin.
Saussurea medusa polysaccharide, the polysaccharide extract of Saussurea medusa Maxim, a traditional Chinese herbal medicine, is used to combat intense ultraviolet radiation, cold, and hypoxia in patients, as well as during drought. This polysaccharide has rich medicinal and ecological values. We aimed to determine whether saussurea medusa polysaccharides can reduce ultraviolet B (UVB)‐induced skin photoaging. Seventy‐five male Kunming mice were divided into five groups: control, UVB‐only, UVB plus vitamin E (VE group), UVB plus saussurea medusa (2 g/kg), and UVB plus saussurea medusa (6 g/kg). The control group was irradiated with normal light, while the other four groups were subcutaneously administered 10 mL/kg/day D‐galactose and irradiated with narrow‐spectrum UVB for 40 min daily. From day 11, the VE group was administered 0.25 g/kg/day vitamin E, while the saussurea medusa intervention groups were administered 2 and 6 g/kg/day saussurea medusa polysaccharide. After 30 days of continuous administration, treatment with saussurea medusa polysaccharides was found to reduce UVB‐induced skin photoaging in mice by elevating the levels of superoxide dismutase, glutathione peroxidase, and hydroxyproline (HYP), while reducing the level of MDA, and inhibiting the EGFR/MEK/ERK/c‐Fos pathway. Overall, our findings suggest that treatment with saussurea medusa polysaccharides positively influences skin photoaging.
Wrinkles on the face and aging of the skin are an undesirable effect of photodamage and ultraviolet radiation. Serum has a quick absorption and ability to penetrate deep layers of the skin, as well as a non-oily finish and a deep formula with a very high amount of active ingredients. Based on these properties, the purpose of this work was to make serum using polyherbal extract. Aloe vera gel, glycerin, olive oil face serum is a highly concentrated cosmetic product. When we use aloe vera we get not only immediate cosmetic effect but also psychological satisfaction. Aloe vera gel is commonly used to treat various skin ailments, sunburn, minor cuts, insect bites, and is also used as a wound healing, anti-inflammatory, anti-bacterial, and anti-fungal effect. Olive oil has anti-inflammatory properties and is used as a skin moisturizing agent. It also has anti-oxidant properties that can prevent premature aging. Facial serum was tested for its pH, physical appearance, spredability, viscosity, microbial testing, cyclic temperature test, etc. The results of the stability study show that there was no change in visual acuity, homogeneity.
Objective:
Hyaluronic acid represents one of the major components of the extracellular environment. The main challenge remains in the ability to deliver these molecules noninvasively across the skin barrier, which can be overcome by the reduction in size to an extent that allows these molecules to pass across the skin barrier. The aim of this study was to measure the penetration and bioavailability of low molecular weight hyaluronic acid to cross an epidermal barrier model.
Methods:
Determining the quantity of hyaluronic acid in the test solutions was carried with method of photocolorimetry analysis. Investigation of the interaction of cells with LMWHA was studied with a confocal microscope.
Results:
The study showed that LMWHA is able to cross the epidermis. Most effective penetration level is during the first 6 hours reaching 75%, and then the concentration started to decline and reached the equilibrium state within the following 2 hours. Confocal laser microscopy demonstrated different distribution and behavior of these molecules among the keratinocytes and fibroblasts.
Conclusion:
Reducing the size of hyaluronic acid to 5 nm enhance their transport across the epidermal layer. The concentration of hyaluronic acid molecules was higher on the fibroblast surface in comparison to their extracellular environment.
In the last two decades, many new peptides have been developed, and new knowledge on how peptides improve the skin has been uncovered. The spectrum of peptides in the field of cosmetics is continuously growing. This review summarizes some of the effective data on cosmeceutical peptides that work against intrinsic and extrinsic aging. Some peptides have been proven in their efficacy through clinical skin trials. Well-known and documented peptides like copper tripeptide are still under research to obtain more details on their effectiveness, and for the development of new treatments. Palmitoyl pentapeptide-4 and Carnosine are other well-researched cosmeceuticals. Additionally, there are many more peptides that are used in cosmetics. However, study results for some are sparse, or have not been published in scientific journals. This article summarizes topical peptides with proven efficacy in controlled in vivo studies.
Ageing, the progressive functional decline of virtually all tissues, affects numerous living organisms. Main phenotypic alterations of human skin during the ageing process include reduced skin thickness and elasticity which are related to extracellular matrix proteins. Dermal fibroblasts, the main source of extracellular fibrillar proteins, exhibit complex alterations during in vivo ageing and any of these are likely to be accompanied or caused by changes in gene expression. We investigated gene expression of short term cultivated in vivo aged human dermal fibroblasts using RNA-seq. Therefore, fibroblast samples derived from unaffected skin were obtained from 30 human donors. The donors were grouped by gender and age (Young: 19 to 25 years, Middle: 36 to 45 years, Old: 60 to 66 years). Two samples were taken from each donor, one from a sun-exposed and one from a sun-unexposed site. In our data, no consistently changed gene expression associated with donor age can be asserted. Instead, highly correlated expression of a small number of genes associated with transforming growth factor beta signalling was observed. Also, known gene expression alterations of in vivo aged dermal fibroblasts seem to be non-detectable in cultured fibroblasts.
Solar UVB is carcinogenic. Nucleotide excision repair (NER) counteracts the carcinogenicity of UVB by excising potentially mutagenic UVB-induced DNA lesions. Despite this capacity for DNA repair, non-melanoma skin cancers and apparently normal sun-exposed skin contain huge numbers of mutations that are mostly attributable to unrepaired UVB-induced DNA lesions. UVA is about 20-times more abundant than UVB in incident sunlight. It does cause some DNA damage but this does not fully account for its biological impact. The effects of solar UVA are mediated by its interactions with cellular photosensitizers that generate reactive oxygen species (ROS) and induce oxidative stress. The proteome is a significant target for damage by UVA-induced ROS. In cultured human cells, UVA-induced oxidation of DNA repair proteins inhibits DNA repair. This article addresses the possible role of oxidative stress and protein oxidation in determining DNA repair efficiency − with particular reference to NER and skin cancer risk.
Currently, the cosmetic industry is overwhelmed in keeping up with the safety assessment of the increasing number of new products entering the market. To meet such demand, research centers have explored alternative methods to animal testing and also the large number of volunteers necessary for preclinical and clinical tests.
This work describes the human skin ex-vivo model (hOSEC: Human Organotypic Skin Explant Culture) as an alternative to test the effectiveness of cosmetics and demonstrate its viability through cutaneous keratinocytes' proliferative capacity up to 75 days in culture.
The skin explants obtained from surgeries were cultured in CO2-humid incubator. After 1, 7, 30 and 75 days in culture, skin fragments were harvested for analysis with histomorphological exam (HE staining) on all days of follow-up and immunohistochemistry for Ck5/6, Ck10 and Ki-67 only on the 75th day.
On the 7th day, the epidermis was perfect in the dermoepidermal junction, showing the viability of the model. On the 30th day, the epidermis was thicker, with fewer layers on the stratum corneum, although the cutaneous structure was unaltered. On the 75th day, the skin became thinner but the dermoepidermal junctions were preserved and epidermal proliferation was maintained. After the 75th day on culture, the skin was similar to normal skin, expressing keratinocytes with Ck5/6 on supra-basal layers; Ck10 on differentiated layers; and viability could be assessed by the positivity of basal cells by Ki-67.
The hOSEC model seems a good alternative to animal testing; it can be used as a preclinical test analogous to clinical human skin test with similar effectiveness and viability proven by immunohistological analyses.
Vitamin C is a potent antioxidant drug that can be used topically in dermatology to treat and prevent changes associated with photoageing. It can also be used for the treatment of hyperpigmentation. Because it is unstable and difficult to deliver into the dermis in the optimum dosage, research is being directed to find stable compounds of Vitamin C and newer methods of delivery of Vitamin C into the dermis.
Skin aging appears to be the result of two overlapping processes, intrinsic and extrinsic. It is well accepted that oxidative stress contributes significantly to extrinsic skin aging, although findings point towards reactive oxygen species (ROS) as one of the major causes of and single most important contributor; not only does ROS production increase with age, but human skin cells' ability to repair DNA damage steadily decreases over the years. We extrapolated mechanisms of intrinsic oxidative stress in tissues other than skin to the skin cells in order to provide effective anti-aging strategies and reviewed the literature on intrinsic skin aging and the role of oxidative stress.
Objective:
The majority of age-dependent skin changes happen in the dermis layer inducing changes in skin collagen and in the proteoglycans. The main aim of this work is to study the efficacy of a Proteum serum, containing soybean fragmented proteoglycans, against skin aging.
Materials and methods:
In vitro tests were performed to evaluate the Proteum serum ability on activating the production of collagen and proteoglycans. An in vivo long term study was performed to determine the efficacy of the Proteum serum when applied on skin. Protection of healthy skin against detergent-induced dermatitis and the antioxidant properties of the applied Proteum serum were also studied.
Results and discussion:
The in vitro tests demonstrated that the Proteum serum was able to elevate the production of molecules which are essential on supporting the dermal extracellular matrix organization. These results were correlated by the in vivo measurements where a clear trend on improving the measured skin parameters due to the Proteum serum application was found.
Conclusions:
A beneficial effect of the applied Proteum serum was demonstrated with an improvement of the skin roughness and a reinforcement of the skin barrier function. Moreover, a significant protector effect on human stratum corneum against LPO was demonstrated.
The performance of two cell viability test kits based on the use of redox indicators yielding fluorescent products, the AlamarBlue assay and a resazurin-based in vitro toxicology assay kit from Sigma, was compared in the present study. Cultures of human, neonatal foreskin fibroblasts were exposed to equal concentrations of the two dye solutions in the cell culture media. The fluorescence intensities of the cell culture media obtained in response to cell proliferation with the two dyes showed a pronounced similarity. Both dyes were noncytotoxic to cell cultures with high initial cell densities for 168 h of continuous exposure, but showed equal levels of cytostatic effects in cultures with a low initial cell density after 72 h of exposure. Similar characteristics of the dye solutions were observed by high-performance liquid chromatography (HPLC) separation and UV spectroscopy, and the major components were tentatively identified as resazurin and resorufin. The AlamarBlue assay has gained wide application as a cell viability indicator that allows continuous monitoring of cell proliferation or cytotoxicity in human and animal cells, bacteria, and fungi, but no studies with the deliberate use of resazurin reduction to measure cell proliferation in cultures of somatic mammalian cells have been published. In the AlamarBlue dye solution, resazurin is supplemented with various stabilizing agents, but the need for their use is questioned.
The literature data suggest the capacity of biomacromolecules to permeate the human skin, even though such a transdermal permeation appears to be governed by physicochemical parameters which are significantly different compared to those ruling the skin permeation of small molecules. On these grounds, the present study was undertaken to investigate the in vitro diffusion properties through the human epidermis of hyaluronic acid and their sulfates. Low- and medium-molecular-weight hyaluronic acids and the corresponding derivatives at two degrees of sulfation were then tested. In vitro studies evidenced that the sulfated polymers permeate better than the corresponding hyaluronic acid, despite their vastly greater polarity, while the observed permeation markedly decreases when increasing the polymer's molecular weight regardless of the sulfation degree. Using a fluorescent-labeled polysaccharide, it was also evidenced that hyaluronans have a great affinity for corneocytes and likely cross the stratum corneum mainly through a transcellular route. The molecular-dynamics study revealed how the observed permeations for the investigated polysaccharides can be rationalized by monitoring their conformational profiles, since the permeation was found to be directly related to their capacity to assume extended and flexible conformations.