Oriflame Cosmetics S.A.

Introduction: Acne is one of the most common skin concerns of unknown etiology, often connected to the menstrual cycle in women, and possibly to the microbial profile and function. Objective: We aimed to investigate how hormonal fluctuation affects hormonal acne-prone skin in different populations in relation to skin clinical parameters and microbial profiles. Methods: We evaluated skin features by using biophysical and topographical tools. For microbial profiling, we sequenced facial skin microbiota and associated the findings with the skin clinical parameters during the different phases of the menstrual cycle. Results: We identified differences between and within hormonal phases in women of Chinese and Caucasian origin. Changes were discovered in transepidermal water loss (TEWL), sebum level, hydration level and pore volume. The most abundant identifiable genera in both ethnicities were Cutibacterium, Staphylococcus and Streptococcus, without any significant abundancy differences within the menstrual cycle. Interestingly, 11 bacterial metabolic pathways were downregulated in Chinese compared to Caucasian skin during the follicular phase. The majority of these pathways were associated with skin redox balance, perhaps indicating a weaker oxidative stress response in Chinese versus Caucasian skin. Novosphingobium taxa were increased in the Chinese skin microbiome, which has been reported to protect skin from pollution mediated oxidative stress. Conclusion: Thus, the present pilot study explored some of the clinical and metagenomic changes in acne-prone skin, and provide guidance to tailor personalized skin care regimes during the menstrual cycle. Also, the skin redox status in acne-prone skin, provides more opportunity to tailor personalized skin care regimes.

Background In human skin, miRNAs have important regulatory roles and are involved in the development, morphogenesis, and maintenance by influencing cell proliferation, differentiation, immune regulation, and wound healing. MiRNAs have been investigated for many years in various skin disorders such as atopic dermatitis, psoriasis, as well as malignant tumors. Only during recent times, cosmeceutical use of molecules/natural active ingredients to regulate miRNA expression for significant advances in skin health/care product development was recognized. Aim To review miRNAs with the potential to maintain and boost skin health and avoid premature aging by improving barrier function, preventing photoaging, hyperpigmentation, and chronological aging/senescence. Methods Most of the cited articles were found through literature search on PubMed. The main search criteria was a keyword “skin” in combination with the following words: miRNA, photoaging, UV, barrier, aging, exposome, acne, wound healing, pigmentation, pollution, and senescence. Most of the articles reviewed for relevancy were published during the past 10 years. Results All results are summarized in Figure 1, and they are based on cited references. Conclusions Thus, regulating miRNAs expression is a promising approach for novel therapy not only for targeting skin diseases but also for cosmeceutical interventions aiming to boost skin health.

Higher demands on skin care cosmetic products for strong performance drive intense research to understand the mechanisms of skin aging and design strategies to improve overall skin health. Today we know that our needs and influencers of skin health and skin aging change throughout our life journey due to both extrinsic factors, such as environmental factors and lifestyle factors, as well as our intrinsic factors. Furthermore, we need to consider our microflora, a collection of micro-organisms such as bacteria, viruses, and fungi, which is a living ecosystem in our gut and on our skin, that can have a major impact on our health. Here, we are viewing a holistic approach to understand the collective effect of the key influencers of skin health and skin aging both reviewing how each of them impact the skin, but more importantly to identify molecular conjunction pathways of these different factors in order to get a better understanding of the integrated “genome-microbiome-exposome” effect. For this purpose and in order to translate molecularly the impact of the key influencers of skin health and skin aging, we built a digital model based on system biology using different bioinformatics tools. This model is considering both the positive and negative impact of our genome (genes, age/gender), exposome: external (sun, pollution, climate) and lifestyle factors (sleep, stress, exercise, nutrition, skin care routine), as well as the role of our skin microbiome, and allowed us in a first application to evaluate the effect of the genome in the synthesis of collagen in the skin and the determination of a suitable target for boosting pro-collagen synthesis. In conclusion, we have, through our digital holistic approach, defined the skin interactome concept, as an advanced tool to better understand the molecular genesis of skin aging and further develop a strategy to balance the influence of the exposome and microbiome to protect, prevent, and delay the appearance of skin aging signs and preserve good skin health condition. In addition, this model will aid in identifying and optimizing skin treatment options based on external triggers, as well as helping to design optimal treatments modulating the intrinsic pathways.

The hydrodistilled essential oils from eighteen samples of Salvia rosmarinus Spenn. collected in six localities of Elba Island (Tuscany, Italy) during three different seasonal periods were analyzed by GC-MS for the first time. Fifty-five components were identified, representing 96.8-99.6% of the total chemical composition. All the tested essential oils were characterized by a high content of monoterpenes (oxygenated 49.2-80.3%; hydrocarbons 18.7-48.3%). Among them, 1,8-cineole (26.4-49.1%), α-pinene (4.5-34.8%), camphor (1.1-18.8%) and borneol (1.7-16.2%) were the main constituents. The high amount of 1,8-cineole/α-pinene/camphor/borneol may suggest the presence of an intermediate rosemary chemotype. Statistical analysis was also performed on the essential oil (EO) composition evidenced an expected difference depending on the collection seasons, to the geographical areas and soil composition. A comparison with the essential oil composition from S. rosmarinus collected in all the other islands of Tuscan Archipelago (Italy) was also reported, together with a Multivariate Statistical Analysis.

Background & Aims Previous investigations have aimed at investigating parameters affecting age perception on several ethnicities. Perceived health has been a newer focus on Caucasian skin, yet little is known on the skin features used to estimate the health status of Chinese women and we aimed to investigate whether these cues are the same as those used for age perception. Methods Age and health appearance of 276 Chinese female volunteers was estimated from their photographs by 1025 female naïve Chinese graders 20–69 years old. Models were built to predict perceived age and health from topographic, colour and biophysical measured variables, in two subsets of the studied volunteers: below and above 50 years. Machine learning‐based predictive models for age and health perception were built on the collected data and the interpretability of the models was established by measuring feature importance. Results Age perception was mostly driven by topographic features, particularly eye bags and eye lid sagging in the group below 50 years old. Wrinkles, notably from the lower part of the face and oval of the lower face, were found to be more relevant in the group above 50 years. Health appearance was primarily signaled by skin imperfections and global pigmentation in the subset below 50 years, while colour related parameters and skin hydration acted as health cues for the subset above 50 years. Conclusion Distinct skin features were acting as cues for age perception and/or health perception and varied per age subset. Their contribution should be borne in mind when designing products for “younger looking skin” and “healthier looking skin”.

Accumulation of senescent cells promotes the development of age-related pathologies and deterioration. In human skin, senescent cells potentially impair structure and function by secreting a mixture of signaling molecules and proteases that influence neighboring cells and degrade extracellular matrix components, such as elastin and collagen. One of the key underlying mechanisms of senescence and extrinsic skin aging is the increase of intracellular reactive oxygen species and resulting oxidative stress. Tert-butyl hydroperoxide (tBHP) is a known inducer of oxidative stress and cellular damage, acting at least in part by depleting the antioxidant glutathione. Here, we provide a detailed characterization of tBHP-induced senescence in human dermal fibroblasts in monolayer culture. In addition, results obtained with more physiological experimental models revealed that tBHP treated 3D reconstructed skin and ex vivo skin developed signs of chronic tissue damage, displaying reduced epidermal thickness and collagen fiber thinning. We, therefore, propose that tBHP treatment can be used as a model to study the effects of extrinsic skin aging, focusing mainly on the influence of environmental pollution.

Background: The use of a skin care routine is commonly promoted by the cosmetic industry, yet there is a lack of clinical evidence to support this practice over the use of a single skin care product. Aims: In the present study, we aimed at showing the clinical benefits of using a comprehensive skin care routine vs a simple one. Methods: Skin micro-/macro-topographic, skin color, and superficial/deep hydration were collected at baseline and after 4 weeks of use, on forty-nine women randomly allocated to two groups. The first one followed the use of an advanced routine (AR: Cleanser/Toner/Eye cream/Serum/Day & Night cream), while the other group was instructed to use a simple routine (SR: Cleanser & Day cream). Results: Hemoglobin heterogeneity was found to be significantly reduced only in the SR group. However, the AR outperformed the SR when it comes to improving superficial hydration, deep hydration, skin roughness, mean pore area, melanin heterogeneity, and crow's feet wrinkle depth. A significant increase in skin brightness from baseline was only recorded when using the AR while both routines significantly improved the nasolabial wrinkles. Conclusion: These findings advocate for using a relevant daily routine as it demonstrates the visible skin benefits over a short period, while driving the creation of habits for the prevention of aging signs.

Background: High demand on anti-aging skin care encourage the improvement and development of more personalized formulations with additional benefits for general skin health and age associated skin signs. The skin aging physical and biological phenotypes manifest differently between diverse ethnic populations. A highly polluted environment can be viewed as an extrinsic factor accelerating the skin aging process. Aim: To develop a unique formula with active complexes, having multifunctional effects for anti-pollution, brightening and anti-aging/barrier strengthening purposes with confirmed activities in vitro and ex vivo skin models, suitable for polluted skin. Methods: In vitro culture model with primary human skin cells, ex vivo studies with full-thickness human skin, melanocyte 3D coculture model, gene expression of epidermal and dermal genes, anti-glycation, proteasomal activity, melanin, and cytokine assays. Results: In vitro and ex vivo studies clearly demonstrated that diglucosyl gallic acid (active A) and the formulation complex inhibited pollution mediated MMP1 protein, CYP1A1 gene expression, and IL-6 protein secretion, while caprylic/capric triglyceride, diacetyl boldine (active B) had anti-melanogenic effect in in vitro primary melanocyte monoculture and 3D spheroid model. Another active compound, acetyl dipeptide 1 cetyl ester (active D), significantly upregulated epidermal barrier genes (Aquaporin 3 [AQP3], Filaggrin [FLG], caspase 14, and keratin 10) in human primary keratinocytes. Interestingly, both acetyl dipeptide 1 cetyl ester (active D) and niacinamide (active C) improved dermal gene expression (fibrillin-1, Collagen type 1 alpha 1, Decorin, Lysyl oxidase-like 1) and, moreover, had significant anti-glycant and proteasomal promoter activity in human primary fibroblasts. Conclusion: Considering consumers need in heavily polluted areas, we developed a multipurpose formulation comprised of unique active complexes toward pollution, pollution induced inflammation, skin brightening, and antiaging concerns with beneficial results demonstrated by in vitro and ex vivo studies.

Background: As the eye contour ages, the skin on the lid becomes lax often causing a voluminous protrusion where the superior palpebral sulcus begins to sag onto the upper eyelid. This sagging feature may present a novel anti-ageing target for cosmetic products when treating the eye area. A quantitative method to evaluate the volume of this sagging feature has not been previously established. We investigate the use of the DermaTOP fringe projector and Antera 3D Camera to this end. Methods: Eyelid topographic measurements were collected on 20 female volunteers aged 50-75 years with the DermaTOP and Antera 3D. The DermaTOP and Antera 3D measurements were assessed for reproducibility and product effect detection capabilities. Results: The DermaTOP and Antera 3D successfully measured sagging feature volume, demonstrated reproducibility of measurement and furthermore were suitably sensitive to allow for detection of sagging feature volume reduction after a single application of aqueous tightening serum. DermaTOP parameters were found to moderately correlated with the Antera 3D parameters. Conclusion: Both the DermaTOP and Antera 3D allow for quantitative measurement of eyelid sagging feature volume and in-turn permit evaluation of anti-ageing cosmetic preparations targeting the eyelid.

Human skin microbiota might play an important role in maintaining skin health and potentially prevent premature skin aging. The use of probiotics in therapeutic skin applications is an attractive idea, as it could offer an alternative option for certain inflammatory skin disorders and dry or sensitive skin. Here, we investigated for the first time, a comparative study of live and the lysate products of probiotic strain Lactobacillus reuteri DSM 17938 in skin topical applications using ex vivo skin models focusing on anti‐inflammatory and skin barrier function and in vitro assays for antimicrobial activity. Our results in ultraviolet‐B radiation (UVB‐R) induced inflammation model demonstrated, that both live bacteria and the lysate of L. reuteri DSM 17938 reduced proinflammatory IL‐6 and IL‐8, illustrated in both reconstructed human epidermis (RHE) and native skin models. Live L. reuteri DSM17938 significantly increased aquaporin 3 (AQP3) gene expression, while the lysate enhanced Laminin A/B levels in a healthy (unstimulated) state of RHE, suggesting a positive impact on skin barrier. In addition, live L. reuteri DSM 17938 had antimicrobial action against pathogenic skin bacteria (Staphylococcus aureus, Streptococcus pyogenes M1, Cutibacterium acnes AS12, Pseudomonas aeruginosa), whereas the lysate did not have such an effect. Therefore, it is hypothesized that L. reuteri DSM 17938 could be beneficial for general skin health, to avoid the UVB‐R mediated inflammatory cascade and/or prevent photoaging, improve barrier function or in the management of unhealthy skin prone to inflammatory conditions due to its antimicrobial, anti‐inflammatory and skin barrier enhancing functions. This article is protected by copyright. All rights reserved.

Objective: In spite of hand care being a dynamic segment of skin care, hands skin physiology has been receiving little attention in comparison to facial skin. In the present study, we aimed at gathering a comprehensive set of skin data from the dorsal part of the hand to study age related-changes in two ethnic groups (Caucasian and Chinese). Methods: Skin topographic, skin colour/colour heterogeneities, skin chromophores and skin biophysical measurements of 116 Caucasian and Chinese female volunteers aged 30-65 years old were collected in Ireland and in China as part of a cross-sectional study. Results: Topographic alterations happened at both micro and macro scales with a noticeable delay in the onset of 10 years for the Chinese cohort. Similar evolution of skin colour with ageing was observed between the two cohorts and strong dissimilarities were seen when it came to colour heterogeneities and melanin hyper concentration, with a 20-year delay in severity for the Chinese cohort. A similar sharp drop of skin hydration occurred when reaching the 60's regardless of the group and substantial differences were recorded for skin biomechanical properties of the skin. Conclusion: These results provide additional insights about hand skin physiology in relation to ageing and ethnic differences, especially when put into perspective with what is currently known about facial ageing. This research yield additional material for hand cream product rationale and strategies for mitigating the appearance of ageing hands.

In 2013, the European Commission launched the Environmental Footprint Rules pilot phase. This initiative aims at setting specific rules for life cycle assessment (LCA: raw material sourcing, production, logistics, use‐ and disposal phase) studies within one product category, so called product environmental footprint category rules (PEFCR), as well as for organisations, so called organisational environmental footprint sector rules (OEFSR). Such specific rules for measuring environmental performance throughout the life cycle should facilitate the comparability between LCA studies, and provide principles for communicating the environmental performance, such as transparency, reliability, completeness, and clarity. Cosmetics Europe, the association representing the cosmetics industry in the EU, completed a voluntary study into the development of PEFCR for shampoo, generally following the guidelines and methodology developed by the European Commission for its own pilot projects. The study assessed the feasibility and relevance of establishing PEFCR for shampoo. Specifically, the study defines a large number of modelling assumptions and default values relevant for shampoo (e.g. for the functional unit, the system boundaries, default transport distances, rinsing water volumes, temperature differences, life cycle inventory data sources etc) that can be modified as appropriate, according to specificities of individual products, manufacturing companies and countries. The results of the study may be used to support internal decision‐making (e.g. to identify ‘hotspots’ with high environmental impact and opportunities for improvement) or to meet information requests from commercial partners, consumers, media or authorities on product environmental characteristics. In addition, the shampoo study also highlighted many of the challenges and limitations of the current PEF methodology, namely its complexity and resource intensiveness. It highlighted two areas where improvements are much needed: (1) data quality and availability, and (2) impact assessment methodologies and robustness. Many of the learnings are applicable to other rinse‐off cosmetic products such as shower gels, liquid soaps, bath products and hair conditioners. This article is protected by copyright. All rights reserved

Background The cause of enlarged pores remains obscure but still remains of concern for women. To complement subjective methods, bioengineered methods are needed for quantification of pores visibility following treatments. The study objective was to demonstrate the suitability of pore measurements from the Antera 3D. Material and methods Pore measurements were collected on 22 female volunteers aged 18‐65 years with the Antera 3D, the DermaTOP and image analysis on photographs. Additionally, 4 raters graded pore size on photographs on a scale 0‐5. Repeatability of Antera 3D parameters was ascertained and the benefit of a pore minimizer product on the cheek was assessed on a sub panel of seven female volunteers. Results Pore parameters using the Antera were shown to depict pore severity similar to raters on photographs, except for Max Depth. Mean pore volume, mean pore area and count were moderately correlated with DermaTOP parameters (up to r = .50). No relationship was seen between the Antera 3D and pore visibility analysis on photographs. The most repeatable parameters were found to be mean pore volume, mean pore area and max depth, especially for the small and medium filters. The benefits of a pore minimizer product were the most striking for mean pore volume and mean pore area when using the small filter for analysis, rather than the medium/large ones. Conclusion Pore measurements with the Antera 3D represent a reliable tool for efficacy and field studies, with an emphasis of the small filter for analysis for the mean pore volume/mean pore area parameters.

Background: Skin topographic measurements are of paramount importance in the field of dermo-cosmetic evaluation. The aim of this study was to investigate how the Antera 3D, a multi-purpose handheld camera, correlates with other topographic techniques and changes in skin topography following the use of a cosmetic product. Methods: Skin topographic measurements were collected on 26 female volunteers aged 45-70 years with the Antera 3D, the DermaTOP and image analysis on parallel-polarized pictures. Different filters for analysis from the Antera 3D were investigated for repeatability, correlations with other imaging techniques and ability to detect improvements of skin topography following application of a serum. Results: Most of Antera 3D parameters were found to be strongly correlated with the DermaTOP parameters. No association was found between the Antera 3D parameters and measurements on parallel-polarized photographs. The measurements repeatability was comparable among the different filters for analysis, with the exception of wrinkle max depth and roughness Rt. Following a single application of a tightening serum, both Antera 3D wrinkles and texture parameters were able to record significant improvements, with the best improvements observed with the large filter. Conclusion: The Antera 3D demonstrated its relevance for cosmetic product evaluation. We also provide recommendations for the analysis based on our findings.

Objective: The desire for a youthful look remains a powerful motivator in the purchase of cosmetics by women globally. To develop an anti-ageing solution that targets the need of end consumers, it is critical to understand which signs of ageing really matter to them and which influence their age perception. To date, such research has not been performed in a Russian population. The aim of this work was to identify the signs of ageing that contribute the most to an 'older' or 'younger' look for Russian women aged 40 years old and above. Methods: The age of 203 Russian female volunteers was estimated from their standard photographs by a total of 629 female naïve assessors aged 20-65 years old. Perceived age data were related to 23 facial skin features previously measured using linear correlation coefficients. Differences in average severity of the correlating skin ageing features were evaluated between women perceived older and women perceived younger than their chronological age. Volunteers' responses to a ranking question on their key ageing skin concerns previously collected were analysed to provide an additional view on facial ageing from the consumer perspective. Results: Nine facial skin ageing features were found to correlate the most with perceived age out of the 23 measured. Such results showed the importance of wrinkles in the upper part of the face (crow's feet, glabellar, under eye and forehead wrinkles), but also wrinkles in the lower half of the face associated with facial sagging (upper lip, nasolabial fold). Sagging was confirmed of key importance to female volunteers aged 41-65 years old who were mostly concerned by the sagging of their jawline, ahead of under eye and crow's feet wrinkle. The severity of hyperpigmented spots, red and brown, was also found to contribute to perceived age although to a weaker extent. Conclusion: By providing a clear view on the signs of ageing really matter to Russian women who are aged 40 years old and above, this research offers key information for the development of relevant anti-ageing solutions specifically targeting their needs and their desire to achieve younger-looking skin.

The purpose of this study was to evaluate the dermal absorption of acetyl aspartic acid (A-A-A) through an in vitro and in vivo evaluation with human skin after 6 and 24 hours topical application of a cosmetic formulation containing A-A-A at 1%. The in vitro experiment was carried out using the Franz diffusion cells system with ex vivo human skin samples. The profile of diffusion of A-A-A was evaluated after 6 and 24 hours. The in vivo experiment was performed on human volunteers following a tape-stripping protocol after 6 hours topical application. A-A-A was quantified in the main skin compartments, i.e. the skin surface, the stratum corneum, the skin and the receptor fluid using LC-MS analysis. The 24 hours in vitro experiment confirmed the great penetration potential of A-A-A in all skin compartments. After 6 hours topical application the removed tape-strips from both in vitro and in vivo experiments were analysed and the profile of diffusion of A-A-A was determined, allowing also an in vitro / in vivo comparison. The diffusion profile observed on the in vitro skin penetration test is highly representative of the in vivo situation evaluated on volunteers. The combination of in vitro with in vivo data confirmed that A-A-A has the capacity to diffuse through the skin after topical application, and reach the dermis as the targeted skin layer for potential anti-aging benefits. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

This paper is devoted to the study of gas flow fields related to helium atmospheric pressure guided streamer (plasma bullet) propagation in the air. For very weak up to moderate helium flows, the modification induced to the gas flow field by the plasma ignition is demonstrated; it is shown that the turbulent flow region is expanded and two conditions must be fulfilled regarding the working gas profile in the air for streamer propagation, i.e., laminar flow and high concentration in this laminar flow region.

The pathophysiology of cellulite involves changes in the subcutaneous adipose layer and the extracellular matrix (ECM) that supports it together with overlying dermal layer. Cellular mechanisms governing cellulite are not fully understood. However, it is accepted that changes include enhanced lipogenesis, decreased lipolysis, and increased lipid storage within the adipocytes as well as changes in the dermal architecture. In our studies the ability of cosmetic agents Furcellaria lumbricalis, Fucus vesiculosus, retinoid, conjugated linoleic acid (CLA), and a glaucine mixture to stimulate in vitro 1) lipolysis in human adipocytes and 2) production of pro-collagen I by fibroblasts was investigated in vitro. The ability of these ingredients to improve cellulite condition in vivo was also determined. Mature adipocytes and 'aged' fibroblasts were used for in vitro studies. The assessment of cellulite in vivo was performed by dermatological grading and ultrasound measurements. Mature adipocytes treated with combined actives resulted in a significant synergistic increase in free glycerol release. On "aged" fibroblasts, combined treatment of F. vesiculosus and F. lumbricalis stimulated pro-collagen I production. CLA increased pro-collagen I production, but the glaucine mixture had no effect. The clinical study demonstrated a significant improvement in cellulite grading by a dermatologist after 8 and 12 weeks vs. vehicle, and ultrasound imaging showed a significant decrease in fat thickness compared with placebo after 12 weeks. Our studies revealed a potent cocktail of ingredients that when combined together can act in vitro to markedly improve lipolysis mechanisms and by way of stimulating pro-collagen I can also have an effect on the surrounding extracellular matrix. The in vitro actions of the ingredients were translated in vivo, where a clinical improvement of cellulite condition was observed.

This chapter details the process of claims substantiation, how claims can be generated, supported and communicated. It looks at the definition of cosmetic claims and what may be required to substantiate them. It details an approach to substantiating cosmetic claims based on an approach developed in the UK by the Cosmetics Toiletries & Perfumers Association (CTPA) in association with the Advertising Standards Authority (ASA). This includes the different classes of claims, the level of evidence required to support the classes and also the quality of evidence required to support a claim. The approach emphasises the fact that the consumer needs and how these are fulfilled is an essential part of the thinking. The chapter also raises the challenges presented by advances in the understanding of skin physiology, the technology that can be applied to influencing this and how this might be communicated to consumers.

Skin-lightening products are commercially available for cosmetic purposes to obtain lighter skin complexion. Clinically, they are also used for treatment of hyperpigmentary disorders such as melasma, café au lait spot and solar lentigo. All of these target naturally melanin production, and many of the commonly used agents are known as competitive inhibitors of tyrosinase, one of the key enzymes in melanogenesis. In this review, we present an overview of commonly used skin-whitening ingredients that are commercialized, but we also hypothesize on other mechanisms that could be important targets to control skin pigmentation such as for example regulation of the adrenergic and glutaminergic signalling and also control of tetrahydrobiopterins in the human skin. Les produits éclaircissants sont disponibles dans le commerce pour des buts cosmétiques afin d’obtenir un tient plus clair. Ils sont également utilisés en clinique, pour le traitement de troubles hyper pigmentaires comme le melasma, les taches café au lait et le lentigo solaire. Tous ces produits ont pour cible la production naturelle de mélanine et beaucoup de ceux généralement utilisés sont reconnus comme des inhibiteurs compétitifs de la tyrosinase, une des enzymes clés de la mélanogénèse. Dans cette revue, nous présentons une vue d’ensemble des ingrédients généralement utilisés et commercialisés comme blanchissant cutanés mais nous formulons aussi l’hypothèse que d’autres mécanismes pourraient être des cibles importantes pour contrôler la pigmentation de la peau comme par exemple la régulation du signal adrénergique et glutaminergique ou le contrôle des tetrahydrobiopterines dans la peau humaine.