International Journal of Cosmetic Science最新文献

Objective: The biodegradability of organic chemicals with usual down-the-drain disposal in their end-of-life is a key parameter to be considered by industries pursuing sustainability in their new product developments. It is a property that, once improved in any formulated product portfolio, will allow for a significant reduction in the presence of its ingredients in the natural environment, with a potential reduction in the pollution-related environmental impact after consumption. This article aimed to propose an intelligent strategy for addressing biodegradability in the cosmetics sector, with the potential to support both product claims and corporate sustainability initiatives.

Methods: The framework for achieving a portfolio biodegradability indicator is composed of three levels of assessment, the first being an ingredient level assessment, the second being an individual product biodegradability calculation (PBI-Product Biodegradability Index), and finally a third level to calculate an emission-based, company-wide biodegradability indicator (GBI-Global Biodegradability Index). A case study is presented and discussed in detail, as a proof of applicability of the whole framework to support new developments for an improved environmental performance. Important insights in terms of ingredients assessment criteria are also presented.

Results: A fictitious portfolio composed of two soaps (a bar and a liquid), two hair care products (shampoo and hair conditioner) and one bath oil resulted in a GBI of 92.8%. The bar soap was the main contributor for this global index, with a PBI of 98.8% and a relatively high consumption volume of 1 ton/year, which accounts for approximately 66% of the total portfolio consumption. Other products, like hair care, presented lower PBIs, but their lower mass consumption representativeness within the portfolio prevented a significant negative impact on the global index. The main strategic directions derived from the case study, to ensure a stable and high biodegradability of the consumed organic mass, were properly discussed.

Conclusion: The output of this framework provided an intelligent management strategy for innovation, where reformulation efforts can be targeted at products and ingredients with the highest potential to improve the biodegradability profile of the total organic mass released to the environment from a given portfolio.

Objective: Substantial efforts have been progressively devoted to developing innovative, safe, and effective topical anti-aging products that not only improve the appearance of aged skin but also prioritize environmental sustainability and the responsible use of natural resources. Thus, the current study targeted to evaluate novel, natural emulsion/serum comprising new glycolipid emulsifier (lauryl glucoside/myristyl glucoside/polyglyceryl-6 laurate) and Acmella oleracea plant extract as a model active.

Methods: The developed serum was assessed concerning its stability (freeze-thaw test, accelerated study), safety (in vitro screening of eye irritation potential, dermal absorption study) and efficacy (randomized, active/reference-controlled, half-face, in vivo study). Changes in skin biophysical properties, microrelief, roughness, texture, surface, and volume parameters were assessed in the periocular and perioral areas of human volunteers after 2 weeks of product application, utilizing several bioengineering and topography techniques.

Results: The stability study demonstrated favourable stability profile of the developed serum, with practically unaffected stability-indicating parameters (apparent viscosity, yield, flow point, storage and loss moduli, loss factor, pH, electrical conductivity) during freeze-thaw cycling and after 3 months of storage at 45°C. The hen's egg test on the chorioallantoic membrane of fertilized chicken eggs confirmed the absence of ocular irritation potential of investigated serum; no effects of haemorrhage, lysis or coagulation were occurred. Skin permeation study using diffusion cells revealed no permeation of spilanthol from the tested A. oleracea extract-loaded serum through the pig ear skin into the receptor medium, thus suggesting no absorption into systemic circulation. In vivo efficacy study corroborated beneficial effects of evaluated serum on the condition/appearance of facial skin, at both periocular and perioral areas-significant (p < 0.05) increase in skin hydration (10%-40%) and smoothness (~15%); significant (p < 0.05) decrease in roughness (20%-30%), scaliness (~30%), and wrinkles (~15%)-implying more hydrated, smoother, visibly milder skin.

Conclusion: The present findings confirmed the stability, preliminary safety (no ocular irritation, no dermal absorption, and good skin tolerability), and efficacy (improved skin hydration and microrelief) of the A. oleracea extract-loaded, glycolipid-based serum, supporting its potential as a safe and effective topical anti-aging product.

Objectives: Hair density estimation is crucial in dermatology and trichology; however, manual counting is time-consuming and error-prone. Although automated approaches have been developed using image processing, neural networks, and deep learning, creating a robust and widely applicable method remains challenging. This study explored the use of XGBoost to estimate hair density with the aim of developing a more accurate and versatile approach.

Methods: The study utilized 895 scalp images to extract features and developed an XGBoost model for hair density estimation using 745 images to train the model and testing its performance on 150 images to evaluate the accuracy, error rate, and scatter plot.

Results: The XGBoost model outperformed previous methods, achieving 89.5% accuracy on the training set and 95.3% accuracy on the test set. This surpassed the results of Kim et al. (52.4%), Urban et al. (79.6%), and Sacha et al. (88.2%) for the test set.

Conclusion: The XGBoost algorithm proved to be effective for automated hair density estimation, achieving an accuracy of 95.3% on the test set. This approach, which focusses on scalp coverage and erosion features, can streamline and improve the objectivity of clinical hair analysis.

Objective: Existing methods to evaluate skin care products suffer limitations. This is the case for ex vivo skin explants, a first-choice 3D model. While essential to analyse mid- to long-term biological effects, this classical model hinders assessing microrelief variations. To circumvent these limitations, we developed an ex vivo PERFused EXplant setup (Perfex) that maintains the outer skin surface in the open air, closely mirroring physiological conditions.

Methods: A custom-designed reservoir enables perfusing the dermal side of explants with buffered, temperature-controlled medium, while the epidermis is subjected to "normal" conditions. Skin tension and characteristics of the stratum corneum, microrelief, histology and immunohistology (collagen types I and III, elastin and fibrillin-1) were analysed and compared to those of explants maintained under conventional conditions or in vivo skin. The effects of skin care formulas intended to induce short- and/or mid- to long-term effects were also assessed.

Results: Skin explants maintained with the Perfex setup exhibit characteristics (firmness, elasticity, hydration and barrier function) closer to those of in vivo skin than with conventional conditions. Moreover, Perfex-maintained explants present no alteration in histology after 7 days and slight variation in the expression of key protein markers. Microrelief characteristics also remain mostly stable over 7 days. Formula applications corroborate that skin tensor-containing products primarily induce short-term changes in the microrelief, while those with biologically active ingredients mainly lead to mid- to long-term effects on the histology and expression of molecular markers. Furthermore, maintaining skin explants with a physiologically relevant skin surface enabled analysing the relationship between microrelief and key markers, showing that fibrillin-1 is the protein most correlated with microrelief characteristics.

Conclusions: The Perfex setup allows for similar preservation of skin explant histology and key protein expression as the conventional system, yet it maintains a skin surface close to that of in vivo skin. Therefore, it is valuable to analyse both the short- and mid- to long-term impacts of skin care formulas and better comprehend their effects. The Perfex system also offers a new tool for investigating fundamental questions, such as the link that can exist between dermal proteins and skin surface properties.

Objective: The aim of this work was to investigate the solubility and co-solubilization of fragrance raw materials (FRMs) in sodium dodecyl sulfate (SDS) and polysorbate 20 (P20) surfactant micellar systems, which can advance our knowledge of multi-solute micellar solubilization and fragrance olfactory performance from product matrices containing the surfactants.

Methods: The transfer of individual FRMs and binary FRM mixtures into micellar phases was quantified by UV-VIS differential spectroscopy and evaluated in terms of the standard Gibbs free energy change and micelle-water partition coefficient. Co-solubilization effects were further evaluated by the deviation ratio.

Results: Anionic SDS was found overall to be a more efficient solubilizer than nonionic P20. On an individual basis, micellar solubilization generally increased with solute lipophilicity but was additionally impacted by solute rigidity and steric effects. Micellar solubilization was favoured for more rigid structures and less favoured for FRMs that exhibited larger molecular rotation and steric hindrance. For multi-solute systems, three co-solubilization effects were observed: (i) inhibitive effect in which micellar partitioning of both solutes decreased, (ii) an inverse effect where partitioning of one solute increased while the other decreased and (iii) synergistic effect in which partitioning of both solutes increased. During co-solubilization in P20 micelles, many FRMs competed for solubilization between the polyoxyethylene chains in the outer layer of the micelle, thereby resulting in an inhibitory effect for both solutes. Co-solubilization of FRM binary mixtures in SDS micelles often resulted in a synergistic increase in micellar solubility, possibly due to micellar swelling, thereby facilitating partitioning of additional solutes into the micelle. An inverse effect in which the micellar solubility of one solute increased, while the other decreased was observed in both surfactant systems with varying degrees of partitioning depending on the composition of the FRM mixture.

Conclusions: The results of this study provide valuable insights into the impact of FRM composition on multi-solute partitioning behaviour and the impact of surfactant type on co-solubilization in micellar solutions.

Objective: Oxidative stress is implicated in scalp and hair health manifesting in several ways, including skin barrier, hair retention, healthy hair appearance and scalp sensation. We previously linked markers of oxidative damage to dandruff and skin barrier impairment and have linked key anti-dandruff technologies to the resolution of these issues. Here we expand the therapeutic space demonstrating many botanical extracts offer protective benefits against ROS stress via both chemical and biological antioxidant mechanisms.

Methods: Chemical antioxidant activity of 10 botanical extracts was measured using oxygen radical absorbance capacity (ORAC) and biological antioxidant activity was measured using a Nrf-2 cell assay. A three-dimensional human keratinocyte skin equivalent model from MatTek was used to measure efficacy of reducing reactive oxygen species (ROS) from both the botanicals added as a solution and from a shampoo product. A 4-week consumer study with 56 panels was conducted with a leave-on treatment containing a botanical extract. Measurement of the oxidized lipids (9 and 13-Hydroxy-10E 12Z-octadecadienoic acid, HODE) extracted from scalp tape strips was made using gradient reversed-phase high-performance liquid chromatography with tandem mass spectrometry (HPLC/MS/MS).

Results: We demonstrated in vitro that many botanical extracts exert antioxidant activity by quenching radicals in ORAC testing as well as activating biological antioxidant pathways via nrf-2 up-regulation in a cellular reporter system. Furthermore, we demonstrate these antioxidant activities for these botanicals in 3D skin models and ultimately show the reduction of lipid oxidation products in a consumer use context with a rosemary extract.

Conclusion: Improved scalp condition can be achieved with incorporation of botanicals having the potential to exert antioxidant activity in hair/scalp care products.

Objective: Moisturizers are integral to daily skincare routines, reflecting the increasing trend among people towards cosmetic products, particularly for skin care. They significantly contribute to preserving skin health, particularly by regulating the epidermal barrier and moisture levels within the skin. This study aims to explore the moisturizing and antioxidant effect of skin barrier restoring cream Moiz MM (MZ) with shea butter, silkflo and vitamin E by investigating its protective effect against oxidative stress-induced cellular damage and therapeutic mechanisms in human keratinocytes cells (HaCaT).

Methods: The in vitro antioxidant activity of MZ was evaluated by DPPH, ABTS and NO assays. For the cell culture study, HaCaT cells were cultured and stimulated using H₂O₂ and then treated with different concentrations of MZ. Then, it was subjected to DCFH-DA staining, reverse transcriptase PCR and western blot analysis for the evaluation of various skin-moisture-related components in human keratinocyte cells. Type I procollagen was examined using ELISA technique.

Results: The results highlighted that oxidative stress in HaCaT cells decreased type I procollagen synthesis, while MZ treatment significantly increased the synthesis. Moreover, the viability of HaCaT cells was not affected in the presence of MZ, which demonstrates its non-toxic effect. Furthermore, MZ can counteract H₂O₂-mediated oxidative stress by enhancing the antioxidant enzyme activity such as superoxide dismutase and catalase, and decrease reactive oxygen species generation in skin cells. Additionally, MZ greatly promotes hyaluronic acid production by enhancing the expression of the hyaluronic acid synthase-1 gene and Aquaporin 3 protein.

Conclusion: This study suggests that MZ has the potential to serve as a moisturizing and antioxidant skincare formula.

Objective: The rate process of moisture sorption by human hair has been analysed in order to hints for helping deepen knowledge on the hair structure and to explain the behaviour of hair in response to moisture.

Methods: The isotherms of moisture sorption by hair were recorded, via dynamic vapour sorption (DVS), for untreated (virgin) and treated (heat-shaped and bleached) hair, as well as for separated cuticle and cortex.

Results: By considering that, during moisture uptake, the hair fibres also swell, it is possible to introduce a time-dependent rate constant for describing the kinetics of the moisture sorption. This model allows for clearly separating the moisture sorption processes occurring in Cuticle and in Cortex and for proposing a role of chain entanglement in the two main compartments of the fibre. It may also provide some hints on the structural changes occurring in the fibre after different cosmetic treatments. The influence of the weight of the sample on the kinetics of the sorption process has also been noted and quantified. The analysis pointed to a transition occurring at around 30% relative humidity, assigned to the opening of the hair inner structure, and accommodation of more water molecules. This allowed for an estimate of the value of the activation energy of the water molecules reacting with the active sites, which was found to be in good agreement with results published in the literature.

Conclusion: The analysis of the kinetics of moisture sorption by hair was shown not only to provide information on the chain entanglement inside the fibre and the effect of cosmetic treatments but also to demonstrate and quantify the influence of fibre density on the sorption process. It is thus suggested that, along with examination of the hysteresis, the analysis of sorption kinetics helps reveal a more complete picture of hair moisture management.

Objectives: The hair shaft is often exposed to shampoo and haircare products that have unknown or varying pH levels. These products contain a combination of surfactants and other active ingredients to treat the hair or the scalp. As amphoteric proteins, hair keratins have limited buffering capacity, so variations in pH can have multifaceted impacts on them. However, there is limited knowledge about how pH affects keratins and keratin-associated proteins (KAPs). Therefore, this study aims to examine the effects of varying pH levels (pH 3-pH 12) on hair structure and analyse consequent alterations in the hair proteome using mass spectrometry-based proteomics.

Methods: A scanning electron microscope was used to examine changes in hair-shaft morphology due to exposure to various pH levels, while mass spectrometry was employed to analyse protein alterations.

Results: We found that exposing the hair shaft to varying pH levels led to specific effects on the cuticle, including cuticle lifting at certain pH levels, while proteomics analysis identified alterations in the hair proteome along with significant deamidation of keratins types I and II and KAPs. More pronounced effects were observed at extreme acidic conditions (pH 3) and alkaline conditions (above pH 8) on both hair morphology and hair proteins. pH levels between pH 5 and pH 7 had minimal impact on hair structure and proteins, suggesting that haircare products with pH in this range are ideal for hair-shaft health. In contrast, alkaline pH levels were found to negatively affect hair.

Conclusions: The structure evaluation and proteomics data emphasize the critical role of pH in hair health. The extreme acidic or alkaline pH impacts the hair structure and hair proteins. The study highlights the optimal pH range for maintaining healthy hair.

Objective: Clinical assessment of wrinkle depth is essential for efficacy evaluations of anti-ageing products. Standardized photographic scales, representative of different wrinkle depths are often used by experts to assign subjects reliable grades. These tools, based on real pictures, usually exist as hard copies (printed books or sheets) for in vivo gradings. Our project aims at developing a methodology to create digital standardized computer-generated scales, allowing photograph and real-life gradings, and providing raters with greater comfort, accessibility, and flexibility in their construction, thanks to the artificial intelligence significative contribution.

Methods: A completely new approach, based on machine learning, allows the creation of Standardized ColorFace® AI-based Wrinkle Assessment (SCAWA) scales. Instead of using real photographs, the scale images are computer-generated. A generative adversarial network (GAN) is trained to create realistic wrinkle samples that are finely controllable by exploring the GAN latent space. Finally, the scale images are selected among hundreds of artificial images depicting natural wrinkle appearances, such as the illustrated wrinkle evolution is well-detailed (small gaps between grades), morphologically stable, and mathematically linear according to a criterion of wrinkle conspicuous depth.

Results: The created 12-point scale for crow's feet wrinkle evaluation on ColorFace® pictures is proven to be realistic, linear, and robustly and accurately usable for photograph assessments. The scale coherence in terms of image ranking has been validated, as well as its reliability and acceptability in real conditions of use. Additionally, the wrinkle grades obtained by the SCAWA scale are well correlated (R = 0.94) with the ones obtained by the Skin Aging Atlas on the same pictures. The AI methodology and digital format brought also interesting side results, such as an enhanced harmonization between experts and a higher representativeness, that is, a decrease of out-of-range pictures.

Conclusion: SCAWA scale makes the most of machine learning to provide an innovative digital tool to ease wrinkles in visual assessment of pictures, while optimizing linearity, homogeneity, and accuracy aspects. The experts' enthusiastic feedback about the scale format and quality is promising regarding the adaptation of the methodology to other signs and a larger distribution of this tool in the market of cosmetic product efficacy assessment.