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BACKGROUND: Standardized methods for sun protection factor (SPF) testing are still beset with endpoint and method-driven issues, and can be influenced by multiple factors. The purpose of this analysis is to explore the factors influencing the results of sun protection factor (SPF) testing in human subjects according to the ISO 24444:2019 standard. Intrinsic factors, such as baseline skin color, age and gender, the minimal erythemal dose on an unprotected area (MEDu), as well as environmental factors such as season/weather influences, are considered for analysis. METHODS: Datasets generated for two reference products (P2 and P8) during the conduct of 50 such studies using the ISO standard 24444:2019 for the testing of SPF products, from a single testing center located in Bucharest, Romania between April 2021 and December 2022, were retrieved and compiled. Overall, the data for 334 subjects was available, with 276 observations for the reference P8, and 171 for P2. RESULTS: No effects due to gender or age were detected. Seasonal changes, the individual typology angle (ITA°) and MEDu were found to have an influence on the outcome of the SPF values. CONCLUSIONS: This study adds new original data about the impact of intrinsic and extrinsic factors on SPF variations pertaining to ISO reference sunscreen P8 (SPF 50+). The findings suggest that some factors will inevitably impact the results between two SPF experiments for the same product and SPF testing laboratory. The interconnections between the sources of this variation are discussed. The findings of this research help to identify and characterize factors that contribute to SPF testing variability.
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Factor de Protección Solar , Protectores Solares , Humanos , Luz Solar/efectos adversos , Rayos Ultravioleta/efectos adversos , Tiempo (Meteorología)RESUMEN
Skin of colour or pigmented skin has unique characteristics: it has a higher eumelanin-to-pheomelanin ratio, more mature melanosomes, an increased amount of melanin distributed in the upper layers of the epidermis, and more efficient DNA repair compared with lighter skin. However, individuals with skin of colour are at a significant risk of skin damage caused by ultraviolet radiation, including the development of photodermatoses and photoageing changes such as uneven skin tone, and are predisposed to pigmentary disorders. In fact, one of the most common conditions leading to dermatology consultations by patients with skin of colour is photoexacerbated pigmentary disorders. Unfortunately, individuals with skin of colour may be less prone to engage in photoprotective measures, including the use of sunscreens. Physicians are also less likely to prescribe sunscreens for them. There is thus a clear need for better education on photodamage and for more efficient and suitable photoprotection in populations with skin of colour. However, this need has thus far only partially been met, and the development of sunscreen products designed to provide optimal photoprotection for people with skin of colour remains a challenge. Targeted sunscreens for individuals with skin of colour require optimal cosmetic appeal (leaving no white residue and not disrupting skin tone). They should include broad-spectrum [ultraviolet (UV)B/UVA] protection with high sun protection factor, as well as protection against long-wave UVA (UVA1) and visible light, as these wavelengths are capable of inducing or augmenting pigmentary disorders. They may also contain depigmenting agents for patients with pigmentary disorders.
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Trastornos de la Pigmentación , Enfermedades de la Piel , Humanos , Rayos Ultravioleta/efectos adversos , Protectores Solares/química , Pigmentación de la Piel , Piel , Enfermedades de la Piel/etiología , Enfermedades de la Piel/prevención & control , Enfermedades de la Piel/tratamiento farmacológico , Trastornos de la Pigmentación/etiología , Trastornos de la Pigmentación/prevención & control , Trastornos de la Pigmentación/tratamiento farmacológicoRESUMEN
BACKGROUND: Two previously published clinical studies by our group assessed erythema and pigmentation responses in outdoor conditions with three reference sunscreens, comparing their effectiveness under the full spectrum of natural sunlight. These studies followed an almost identical protocol but were conducted in two different locations and in two ethnic groups: broadly, Chinese (Singapore) and White European (Mauritius). We analysed the data from these two study populations to compare differences in skin response according to ethnicity. METHODS: The analysis included 128 subjects (53 were Chinese from Singapore and 75 were White European from Mauritius and Singapore). Products used were the reference sunscreens P3 (sun protection factor [SPF] 15), P5 (SPF 30) and P8 (SPF 50+) from ISO norm 24444:2019. Participants were exposed to outdoor sunlight for 2-3 h, depending on baseline ITA. Endpoints were erythema at 24 h: clinical score and colorimetry (Δa*) and pigmentation at 1 week based on colorimetry (ΔL* and ΔITA). RESULTS: Among those with baseline ITA > 41, there were differences in erythemal response between the Chinese and White European groups, the White European group being more erythematous and also having a higher rate of photoprotection failure particularly at SPFs 15 and 30. CONCLUSION: Differences in skin response to sun influenced by ethnicity should be taken into account when making recommendations on sun safety.
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Etnicidad , Protectores Solares , Humanos , Protectores Solares/uso terapéutico , Rayos Ultravioleta/efectos adversos , Factor de Protección Solar , Eritema/prevención & control , PielRESUMEN
BACKGROUND/PURPOSE: Melasma is a frequent photoexacerbated hyperpigmentary disorder, which can significantly impact on the quality of life. We sought to review the pathogenesis of melasma, and the role of photoprotection in the prevention and treatment of this disorder. METHODS: We conducted a narrative review of the literature. We performed literature searches with PubMed from January 1990 to December 2021 using the keywords "melasma," "pathogenesis," "ultraviolet radiation," "visible light," "photoprotection," and "sunscreens." RESULTS: The physiopathology of melasma includes a complex interaction between genetics, sex hormones, and sun exposure. Visible light, in particular high-energy visible light (HEVL), and long-wave UVA (UVA1) play a key role in melasma pathophysiology, and recent research suggests that melasma shares many features with photoaging disorders. Melasma disproportionately affects dark-skinned individuals. Some 30% to 50% of South Americans and Asians, among other ethnicities, can present with melasma. Dark-skinned patients take fewer photoprotective measures. Also, the majority of melasma patients do not adequately follow photoprotection recommendations, including the application of sunscreen. Intensive use of a broad-spectrum sunscreen can prevent melasma in high-risk individuals, can lessen melasma severity (associated or not with depigmenting agents), and can reduce relapses. CONCLUSIONS: Due to the physiopathology of melasma, sunscreens should be broad-spectrum with high sun protection factor, and provide high protection against UVA1 and VL. Sunscreens should be cosmetically acceptable and leave no white residue. Tinted sunscreens are an excellent choice, as pigments can protect from HEVL and UVA1, and may provide camouflage, but they must offer colors that match the skin tone of each patient.
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Melanosis , Protectores Solares , Humanos , Protectores Solares/química , Rayos Ultravioleta/efectos adversos , Calidad de Vida , Factor de Protección Solar , Melanosis/prevención & control , Melanosis/tratamiento farmacológico , PielRESUMEN
BACKGROUND: Currently, sunscreens' sun protection factor (SPF) and ultraviolet (UV) A protection are tested separately under indoor conditions, without considering external conditions that may affect performance. Studies are often conducted in Caucasian individuals; other racial groups may respond differently. METHODS: An outdoor, double-blind, intra-individual study was performed in 63 healthy Chinese and Caucasian volunteers in Singapore. Subjects underwent one outdoor sun exposure lasting 2-3 hours. ISO reference products P3 (SPF 15), P5 (SPF 30), and P8 (SPF 50+) applied at 2 mg/cm2 were compared against each other and against an untreated exposed area (positive control) and an unexposed area (negative control). Endpoints were investigator global assessment (IGA) of erythema at 24 hours, IGA of pigmentation at 1 week, and colorimetry (a*, L*, and ITA) at 24 hours and 1 week. RESULTS: Clinical erythema and pigmentation scores were statistically significantly different among the three sunscreens, with the highest SPF product providing the highest protection, confirming the discriminatory capacity of the model used. Colorimetric assessment correlated well with clinical evaluation. CONCLUSION: This study confirmed the feasibility of ranking sunscreens (at 2 mg/cm2 ) based on clinical effects of high-intensity outdoor solar radiation. Larger studies are needed to look at differences in erythema and pigmentation reactions between Chinese and Caucasian individuals, which could be relevant for photoprotection.
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Quemadura Solar , Protectores Solares , China , Método Doble Ciego , Eritema/etiología , Eritema/prevención & control , Humanos , Factor de Protección Solar , Protectores Solares/uso terapéutico , Rayos Ultravioleta/efectos adversosRESUMEN
BACKGROUND: In vivo testing of sun protection factor (SPF) values can show considerable interlaboratory variability. We studied the underlying reasons and clinical implications. METHODS: Following the ISO 24444:2010 SPF testing method, seven contract research organizations (CROs) tested eight sunscreens marketed as SPF50 or SPF50+ and the reference SPF15 sunscreens P2 and P3 and SPF43 P6. We analysed differences in the products and CRO testing methods with regard to SPF variability. We tested the erythema prevention capacity of five of the products in subjects exposed to high doses of natural sunlight in Mauritius. RESULTS: Sun protection factor values varied dramatically between different CROs for some, but not all of the sunscreens. Those with the largest variability had an SPF50+, and their SPF values differed from a maximum of 62.4 to a minimum of 5.5. These products did not share a common sun-filter composition, and some CROs used low and others high irradiation dose regimens. When comparing these two regimens, test products fell into two categories: (i) they either behaved similarly ("linear") or (ii) they behaved differently ("exponential"). In the outdoor clinical study, exponential and linear sunscreens did not differ in their photoprotection capacities. CONCLUSION: Differences in reported SPF values depend on the linear vs exponential behaviour of such products if subjected to low- vs high-dose test regimens. Under real-time exposure to natural sunlight, exponential and linear sunscreens did not differ in their erythema prevention capacity. Laboratory SPF testing of exponential sunscreens bears the risk of underestimating their in-use SPF.
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Seguridad de Productos para el Consumidor , Factor de Protección Solar/normas , Quemadura Solar/prevención & control , Protectores Solares/administración & dosificación , Protectores Solares/química , Tecnología Farmacéutica/métodos , Etiquetado de Medicamentos , Eritema/prevención & control , Humanos , Piel/efectos de la radiaciónRESUMEN
Seborrheic dermatitis (SD) is a chronic, recurrent, inflammatory skin disorder occurring in areas rich in sebaceous glands. It manifests clinically as erythematous macules or plaques with varying levels of scaling and associated pruritus. Although the pathogenesis of SD has yet to be fully understood, Malassezia yeasts, hormones, sebum levels, and immune response are known to play important roles. Additional factors including drugs, winter temperatures, and stress may exacerbate SD. Current available treatments include antifungal agents, topical low-potency steroids, and calcineurin inhibitors. We aimed to evaluate the effectiveness of a topical non-steroidal cream in treating facial seborrheic dermatitis (FSD). We performed a case series of 11 patients with mild or moderate FSD and a history of several previous treatments without improvement. The patients were treated for 8 weeks with a topical non-steroidal facial cream (NSFC) containing zinc PCA, piroctone olamine, hydroxyphenyl propamidobenzoic acid, biosaccharide gum-2, and stearyl glycyrrhetinate. Signs and symptoms and tolerance were assessed before, during, and at the end of treatment. All of the patients had improved symptoms of FSD (desquamation, pruritus, erythema, and stinging sensation); 81.8% showed an excellent response and 18.1% showed a good response. None of the patients had adverse effects. J Drugs Dermatol. 2020;19(6): doi:10.36849/JDD.2020.5121.
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Antiinflamatorios no Esteroideos/uso terapéutico , Dermatitis Seborreica/tratamiento farmacológico , Administración Cutánea , Adolescente , Adulto , Anciano , Antiinflamatorios no Esteroideos/administración & dosificación , Niño , Dermatitis Seborreica/patología , Cara , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto JovenRESUMEN
Background: Poor ocular tolerance of sunscreens is partially responsible for poor compliance in use of sunscreens. A three-tiered approach for the testing of ocular tolerance for such products is described that includes an in vitro test for ocular irritation, an in vitro test for the activation of pain receptors, and finally a clinical study involving ocular instillation of the product under controlled conditions followed by ophthalmologic and subjective self-evaluation on a graded scale. We report the results for a new water-based facial sunscreen (SCFW) with very good ocular tolerance. Methods: The ocular irritation potential of SCFW was determined using the EpiOcular™ human cell construct which constituted the first-tier testing. Briefly, the tissues were exposed to SCFW and appropriate positive and negative controls for 15 minutes to 24 hours. After treatment, the tissues were rinsed and cytotoxicity determined. The calculated ET50 value (time at which relative viability decreased 50%) was then used to determine the ocular irritation potential. In the second-tier testing, the sting potential of SCFW was determined by employing the NociOcular assay that measures the activation of TRPV1 (transient receptor potential cation channel subfamily V member 1) specific receptors linked to pain sensation in a neuronal model with over-expression of functional TRPV1 channels. Finally, as the third-tier testing, SCFW was tested in a clinical study with instillation of product into the ocular cul-de-sac and ocular irritation was evaluated after 30 seconds, 15 minutes, and 60 minutes by an ophthalmologist. Participating subjects were also asked to score sensation on a scale of 0 to 3 from slight prickliness to severe stinging. Assay control reference product with known good ocular tolerability (10% baby shampoo) was concurrently tested. Results: In the in vitro topical application assay using the EpiOcular™ construct, no significant cytotoxicity was observed in the tissues exposed to SCFW, indicating minimal ocular irritation potential. In the in vitro NociOcular assay, the cells exposed to the prepared dilutions of SCFW showed minimal TRPV1 specific activity, indicating minimal ocular sting potential. In the in vivo study, no statistically significant differences were found in terms of subjective or objective eye irritation assessment between SCFW and 10% baby shampoo. Conclusion: SCFW showed negligible ocular irritation potential in tier 1, minimal potential to activate pain receptors in tier 2, and good ocular tolerability that was comparable to 10% baby shampoo in tier 3 testing. The results suggest that SCFW has good eye tolerance and that the tiered approach can be used to evaluate facial sunscreens for ocular tolerability.
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Ojo/efectos de los fármacos , Protectores Solares/toxicidad , Anciano , Línea Celular Tumoral , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Canales Catiónicos TRPV/genética , Canales Catiónicos TRPV/metabolismo , Pruebas de Toxicidad/métodosRESUMEN
Chronic exposure to solar ultraviolet (UV) radiation induces changes to the expression of hundreds of genes in the skin and modulates cellular signaling pathways that alter its structure, function and appearance. To counter these effects, we have developed a 3-in-1 night facial serum (3-in-1 NFS) comprising melatonin, bakuchiol and ascorbyl tetraisopalmitate that is designed to attenuate UV-generated free radicals and support new collagen synthesis. In order to better define its mechanism of action and gain insight into how it might influence the biology of photoaged skin, we performed a transcriptomic analysis of ex vivo skin explants that had been exposed to UV light and treated with 3-in-1 NFS each day for 4 consecutive days. Differentially expressed mRNAs and microRNAs (miRNA) were identified by RNA sequencing and a miRNA interactome was developed. Pathway enrichment analysis was performed to identify pathways likely modulated by 3-in-1 NFS. Our analysis revealed that the combination of active ingredients in 3-in-1 NFS exerted a synergistic effect on skin biology and modulated the expression of genes implicated in the regulation of collagen biosynthesis, angiogenesis, skin barrier function and cellular metabolism. Pathway analysis indicated that these events are driven by Hypoxia-Inducible Factor 1α (HIF-1α) whose expression in UV-exposed skin was partially restored upon 3-in-1 NFS treatment. To our knowledge, 3-in-1 NFS is the first non-drug demonstrated to act upon this pathway in the skin.
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Expresión Génica/efectos de los fármacos , Melatonina/farmacología , Palmitatos/farmacología , Fenoles/farmacología , Transducción de Señal/efectos de los fármacos , Piel/efectos de la radiación , Rayos Ultravioleta , Adulto , Sinergismo Farmacológico , Femenino , Expresión Génica/efectos de la radiación , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Técnicas In Vitro , MicroARNs/metabolismo , Palmitatos/química , ARN Mensajero/metabolismo , Transducción de Señal/efectos de la radiación , Piel/efectos de los fármacos , Piel/metabolismoRESUMEN
Objective: To evaluate the safety and efficacy of ISDINCEUTICS Melaclear® serum (Barcelona, Spain) on skin brightness, skin quality, and signs of facial aging. Design: This was a single-center, observational, open label, prospective clinical study. Ten healthy females (ages 30-70) with moderate signs of facial aging and moderate photodamage (hyperpigmentation and/or sun spots) were enrolled. Treatment consisted of topical twice-daily application of Melaclear serum, morning and evening, to the face and neck for 12 weeks. Efficacy assessments were conducted at weeks 4, 8, and 12. Standardized photographs, expert investigator grading, tolerability assessments, and subjects reported outcome measures were performed at all visits. Adverse events (AEs) were monitored throughout. Visual assessments of the face and neck included grading for radiance, smoothness, pigmentation, erythema, pore size, skin clarity, skin brightness, skin tone, luminosity, skin complexion, photodamage, hyperpigmentation, wrinkle severity, pigment via the modified Melasma Area and Severity Index (MASI), and overall global aesthetic improvement (GAIS). Safety and tolerability assessments included an evaluation of face and neck for stinging/burning by the subject and dryness, scaling, edema, and erythema by the treating investigator at all study visits. Results: All enrolled subjects completed the study. At the 8 and 12-week follow up visit, there was a statistically significant improvement in the investigator GAIS (1.1 and 1.3, respectively) for the face from baseline. MASI scores were all statistically significantly reduced in the face from week 8 onward relative to baseline. In addition, all skin quality parameters assessed in the face significantly improved from baseline to week 12. Subject global aesthetic improvement scale scores (SGAIS) were also significantly improved at week twelve from baseline (1.8 change) as were skin quality assessments. The average rating for patient satisfaction was 2, or "satisfied" with the overall treatment effectiveness from week 4 onwards. For the neck none of the investigator or subject assessments improved significantly at any time point. No adverse events, tolerability events, or unexpected side effects were observed or reported for any of the subjects. Conclusion: Twice a day treatment of women with moderate facial photoaging and hyperpigmentation with Melaclear serum can significantly improve skin quality, reduce the severity and intensity of hyperpigmentation, and improve signs of photodamage within 12 weeks without any side effects. J Drugs Dermatol. 2018;17(12):1310-1315.
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Fármacos Dermatológicos/uso terapéutico , Dermatosis Facial/tratamiento farmacológico , Hiperpigmentación/tratamiento farmacológico , Envejecimiento de la Piel , Preparaciones para Aclaramiento de la Piel/uso terapéutico , Administración Cutánea , Adulto , Anciano , Fármacos Dermatológicos/administración & dosificación , Cara , Dermatosis Facial/patología , Femenino , Humanos , Hiperpigmentación/patología , Persona de Mediana Edad , Cuello , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Método Simple Ciego , Preparaciones para Aclaramiento de la Piel/administración & dosificación , Resultado del TratamientoRESUMEN
BACKGROUND: Accumulation of advanced glycation end-products (AGEs) in skin has been associated with skin aging. Inhibition of glycation of proteins of extracellular matrix may help skin texture and appearance. The objective of the study was to demonstrate the antiglycation activity of topically applied carnosine and novel facial cream (FC) containing carnosine in human skin explants ex vivo. METHODS: Glycation was induced in human skin explants by methylglyoxal (MG) in culture media. FC containing carnosine (FC-CARN) or carnosine in aqueous solution (AQ-CARN) was applied topically on skin explants. Levels of AGEs carboxymethyl-lysine (CML) and pentosidine were determined in the epidermis and dermis of skin sections and were used to calculate antiglycation activity. RESULTS: Exposure to MG led to increases in CML and pentosidine in skin explants. Antiglycation effect for AQ-CARN was CML: -64 and -41%, pentosidine: -48 and 42% in epidermis and reticular dermis respectively. Antiglycation effect for FC-CARN was CML: -150 and -122%, pentosidine: -108 and -136%, in epidermis and reticular dermis respectively. CONCLUSION: Topically applied carnosine protects against the glycation induced by MG. Novel FC-CARN significantly reduced levels of AGEs in both epidermis and reticular dermis in human skin explants.
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Carnosina/administración & dosificación , Productos Finales de Glicación Avanzada/metabolismo , Crema para la Piel/administración & dosificación , Piel/efectos de los fármacos , Administración Tópica , Adulto , Femenino , Humanos , Piel/metabolismo , Envejecimiento de la PielRESUMEN
Common in ageing patient, the solar lentigo is a macular hyperpigmented skin lesion that results from chronic exposure to ultraviolet irradiations. Despite sharing numerous features with other pigmented spots, the diagnostic of this benign lesion is well characterized at the tissue level. Recent studies shed lights on several factors and their pathogenic mechanisms involved in the development of the solar lentigo. This review summarizes how diverse experimental approaches allowed the identification of several biomarkers, which contribute to a better understanding on the initiation and the maintenance of this pigmentary disorder.
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Lentigo/diagnóstico , Lentigo/fisiopatología , Lentigo/terapia , Envejecimiento de la Piel , Anciano , Animales , Biomarcadores/metabolismo , Biopsia/métodos , Dermatología/métodos , Fibroblastos/citología , Humanos , Queratinocitos/citología , Ratones , Trastornos de la Pigmentación/diagnóstico , Trastornos de la Pigmentación/fisiopatología , Trastornos de la Pigmentación/terapia , Luz Solar/efectos adversos , Rayos Ultravioleta/efectos adversosRESUMEN
BACKGROUND: The diverse causes of hyperpigmentation and complex nature of melanogenesis make it a challenge to manage. Current approaches either fail to deliver effective pigmentation control or have undesirable safety profiles that preclude their long-term use. AIMS: To evaluate the capacity of a cosmetic gel serum comprising tranexamic acid, niacinamide, 4-butylresorcinol, phytic acid, and a mixture of hydroxy acids that was designed to target the biological processes regulating skin melanogenesis to attenuate melanin production in vitro and reduce hyperpigmentation clinically. METHODS: Capacity to reduce melanin production in vitro was determined in melanocyte-containing reconstructed human epidermis (RHEm). Clinical efficacy and skin tolerability following twice daily application were assessed in 35 subjects with slight to moderate facial hyperpigmentation by instrumental (VISIA®-CR, Mexameter®) and clinical (mMASI, clinical score, IGA for hyperpigmentation) evaluation on D14, D28, D56, and D84. Maintenance of pigmentation control was followed up 1 month after cessation of treatment on D112. RESULTS: In RHEm in vitro, melanin production was reduced by 50.0% from baseline (D0) on D14 (p < 0.001) and by 67.0% on D21 (p < 0.001). Clinical reductions from baseline in brown spots count (-9.0%; p < 0.05), brown spots area (-16.7%; p < 0.001), and the melanin index (-11.4%; p < 0.001) were observed within 14 days of use. Statistically significant improvements in all clinical parameters were achieved by D28. By the end of treatment on D84, the number and surface area of brown spots were reduced by 28.4% and 40.3% compared to D0, respectively (p < 0.001, both), the melanin index was reduced by 31.1% (p < 0.001), mMASI was reduced by 63.0% (p < 0.001), and skin luminosity was increased by 79.0% (p < 0.001). IGA was reduced from 2.3 on D0 to 1.3 on D84 (p < 0.001). Improvements to all these parameters were maintained until D112, 1 month after termination of treatment. The product also demonstrated very good skin tolerability. CONCLUSION: A gel serum comprising tranexamic acid, niacinamide, 4-butylresorcinol, and hydroxy acids, designed to target the biological processes regulating skin melanogenesis, demonstrates rapid, robust, and sustained pigmentation control in this cohort.
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Hiperpigmentación , Melaninas , Melanocitos , Niacinamida , Resorcinoles , Pigmentación de la Piel , Ácido Tranexámico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Administración Cutánea , Combinación de Medicamentos , Epidermis/efectos de los fármacos , Epidermis/metabolismo , Geles , Hiperpigmentación/tratamiento farmacológico , Melanocitos/efectos de los fármacos , Melanocitos/metabolismo , Melanogénesis , Niacinamida/administración & dosificación , Niacinamida/farmacología , Niacinamida/efectos adversos , Resorcinoles/administración & dosificación , Resorcinoles/efectos adversos , Resorcinoles/farmacología , Preparaciones para Aclaramiento de la Piel/administración & dosificación , Preparaciones para Aclaramiento de la Piel/farmacología , Preparaciones para Aclaramiento de la Piel/efectos adversos , Pigmentación de la Piel/efectos de los fármacos , Ácido Tranexámico/administración & dosificación , Ácido Tranexámico/efectos adversos , Ácido Tranexámico/farmacología , Resultado del TratamientoRESUMEN
The medical literature on aesthetic dermatology has primarily focused on a light-skinned patient population, yet patients of darker skin types have different needs and priorities. In Chinese individuals, key concerns include altered pigmentation, which is perceived to age the individual, and also relates to the Chinese cultural standard of beauty of fair skin; many seek aesthetic treatment for this. Non-invasive cosmetic procedures such as lasers and injections are also gaining in popularity in the Chinese market, but this population is prone to hyperpigmentation as an adverse effect of such procedures. Considered and tailored approaches, both to primary concerns of photoaging and the side effects of cosmetic treatments, are warranted.
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INTRODUCTION: Plants are a source of natural ingredients with retinol-like properties that can deliver anti-aging benefits without the side effects typically associated with retinoid use. We hypothesized that by combining two such analogs, bakuchiol (BAK) and Vigna aconitifolia extract (VAE), with the potent retinoid retinal (RAL), the anti-photoaging potential of RAL could be enhanced without compromising its skin irritation profile. The purpose of this study was to demonstrate that BAK and VAE potentiate the anti-photoaging activity of RAL. METHODS: Gene expression profiling of full-thickness reconstructed skin was first used to examine the impact of BAK or VAE in combination with RAL on skin biology. Next, the irritative potential of this combination, and its capacity to reverse key signs of photoaging in an ex vivo model was assessed. Finally, a proof-of-concept open label clinical study was performed to evaluate the anti-photoaging capacity and skin compatibility of a cosmetic formulation (tri-retinoid complex; 3RC) containing this complex in combination with other well characterized anti-photoaging ingredients. RESULTS: In vitro profiling suggested that combining 0.1% RAL with BAK or VAE potentiates the effect of RAL on keratinocyte differentiation and skin barrier function without affecting its skin irritation profile. When formulated with other anti-photoaging ingredients, such as niacinamide and melatonin, 3RC reversed ultraviolet radiation-induced deficits in structural components of the dermal extracellular matrix, including hyaluronic acid and collagen. In vivo, it led to a reversal of clinical signs of age and photodamage, with statistically significant improvement to skin firmness (+5.6%), skin elasticity (+13.9%), wrinkle count (-43.2%), and skin tone homogeneity (+7.0%), observed within 28 days of once nightly use. Notably, the number of crow's feet wrinkles was reduced in 100% of subjects. Furthermore, 3RC was very well tolerated. CONCLUSION: These data suggest that 3RC is a highly effective and well-tolerated treatment for photoaging.
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BACKGROUND: Melasma is a common skin disorder characterized by alterations in normal skin pigmentation. The objective was to evaluate the efficacy and safety of a skin whitening serum containing niacinamide, hydroxyphenoxy propionic acid, dipotassium glycyrrhizate, glycolic acid, and 4-n-butylresorcinol applied twice daily combined with a spot-preventing SPF50+ sunscreen for treatment of melasma. METHODS: Twelve healthy Caucasian women with melasma (Fitzpatrick skin types II-IV) were enrolled in this pilot clinical study. Efficacy evaluations were performed at baseline and weeks 4, 8, and 12 of treatment and included clinical and instrumental assessments. RESULTS: All endpoints for melasma hyperpigmentation showed a statistically significant improvement from baseline to the end of the study. There was only one dropout. No signs of irritation or discomfort were observed at baseline, w4, w8, or w12. An overall improvement in melasma was observed both clinically and on reflectance confocal microscopy (RCM). CONCLUSION: This topical skin whitening serum had favorable outcomes for the treatment of melasma hyperpigmentation in adult women, as demonstrated on investigator and instrumental assessments. The results of this pilot study need to be confirmed in randomized, controlled studies with a larger sample size.
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Hiperpigmentación , Melanosis , Adulto , Femenino , Humanos , Hiperpigmentación/tratamiento farmacológico , Hiperpigmentación/etiología , Hiperpigmentación/prevención & control , Melanosis/diagnóstico , Melanosis/tratamiento farmacológico , Proyectos Piloto , Estudios Prospectivos , Preparaciones para Aclaramiento de la Piel/química , Preparaciones para Aclaramiento de la Piel/uso terapéutico , Protectores Solares/efectos adversos , Resultado del TratamientoRESUMEN
INTRODUCTION: Most skin disorders, such as atopic dermatitis, psoriasis, skin cancer or age-related skin issues, are the result of a complex interaction between genetic and environmental factors over time. As an external organ, the skin provides the opportunity to study the link between exposure to the environment and several specific biological responses using an exposome approach. The aim of this review was to identify the state of the art of exposome approaches and elucidate the impact of the new era of exposomics on dermatology. METHODS: Two parallel and independent bibliometric analyses were conducted based on documents extracted from the Core Collection and the Science Citation Index Expanded (SCI-Expanded) databases from the Clarivate Analytics' Web of Science (WOS) platform by using the following search terms "exposome" and "skin exposome". In both searches, we used the topic field that includes title, abstract, author keywords and keywords plus terms and the following filters: "English language" and all documents published up to 30 September 2021. We further analysed and interpreted documents extracted in plain text format. RESULTS: Based on the defined searches, 910 documents were identified as being related to "exposome" and 45 as being related to "skin exposome". Environmental sciences and toxicology were the most impacted research areas, and aging, cancer and respiratory allergies were the most documented diseases while, surprisingly, dermatology was much less impacted. Krutmann et al. were the pioneers in implementing this new concept in dermatology with publication of "The skin aging exposome" in 2017 (J Dermatol Sci. 2017;85:152-61). After this tipping point, the number of publications in dermatology evaluating the impact of exposome factors in many skin disorders has steadily increased. CONCLUSIONS: Exposome studies are rapidly attracting interest in dermatology. The results of these studies will undoubtedly improve our understanding of why and under which circumstances some individuals develop skin disorders and help design tailored prevention strategies for patients suffering from these disorders.
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Solar exposure, for long hours and often at peak times with limited shade available, predisposes athletes to episodic sunburn and chronic damage, causing increased risk of precancerous lesions and skin cancer. Environmental factors and training intensity affect risk. Clothing provides good protection, but changing established "uniforms" may not be possible for reasons of practicality, safety, or simply custom. Although physical activity should be encouraged for its physical and mental benefits, risk of skin damage should be minimised. We review existing behaviours, skin cancer risk, and campaigns in the sporting population and highlight key recommendations to help sun protection practices become engrained in sports practice.
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INTRODUCTION: The shortcomings of standardized sunscreen testing have been discussed in recent years, noting differences between how sunscreens perform in indoor clinical (in vivo) laboratory testing compared with real-life conditions. We previously developed an outdoor clinical method for ranking sunscreens by performance level. We used this method to test the performance of a new broad-spectrum sunscreen against International Organization for Standardization (ISO) reference products P3, P5 and P8. METHODS: Sixty-five healthy volunteers with individual typology angle (ITA) ≥ 28° (light to intermediate skin colour) participated in an outdoor study in Mauritius. Test areas were marked on their backs, which were treated with the different products: one commercially available broad-spectrum sun protection factor (SPF) 50 sunscreen [investigational product (IP)] and the three reference products P3 (SPF 15), P5 (SPF 30) and P8 (SPF 50+) from ISO norm 24444:2019 for SPF testing. The test areas were exposed for 2-3 h, depending on the baseline skin colour. They were also compared with an unprotected positive control area and a non-exposed negative control area. Clinical and colorimetry assessment of erythema and pigmentation were performed at 24 h and 8 days, respectively. RESULTS: Overall, according to this outdoor clinical testing method, the sunscreens' efficacy was ranked in an appropriate order given their established SPF levels, with higher SPFs giving greater protection against erythema and pigmentation. Between the different levels of SPF, the differences were statistically significant, for both clinical and colorimetry assessments. The new broad-spectrum SPF 50 IP performed similarly to the SPF 50+ (P8) reference product. Even the highest SPF products, SPF 50 and SPF 50+, had some instances of photoprotection failure. CONCLUSION: These findings confirm the feasibility of this outdoor clinical testing method in ranking sunscreens and provide further evidence, in addition to standardized SPF and UVA protection factor (UVAPF) testing, on how this new broad-spectrum SPF 50 sunscreen performs in extreme outdoor solar exposure: in line with reference product P8 (SPF 50+). TRIAL REGISTRATION NO: ISRCTN95394014.