RESUMO
Recently, it has been reported that increased expression of WNT1 accelerates the differentiation of melanocyte stem cells (McSCs) in solar lentigines (SLs), hyperpigmented maculae commonly seen on sun-exposed areas of the skin. In this study, to establish an in vitro SL model, human epidermal squamous carcinoma cell line HSC-1, which expresses higher levels of WNT1 than normal human epidermal keratinocytes, was co-cultured with early passage normal human epidermal melanocytes (NHEMs) as an in vitro McSC model. As a result, mRNA expression levels of melanocyte differentiation-related genes MITF and TYR in NHEMs were significantly increased by co-culturing with HSC-1 cells. Furthermore, Phalaenopsis orchid extract (Phex) inhibited McSCs differentiation by suppressing WNT1 expression via down-regulation of DLX2, a transcriptional activator of WNT1, in HSC-1 cells. Therefore, our finding suggested that extracts such as Phex, which suppresses WNT1 expression, may be useful as a novel treatment of SLs.
Assuntos
Antígenos de Superfície/genética , Diferenciação Celular/efeitos dos fármacos , Melanócitos/efeitos dos fármacos , Orchidaceae/química , Substâncias Protetoras/farmacologia , Proteína Wnt1/genética , Antígenos de Superfície/metabolismo , Diferenciação Celular/efeitos da radiação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Técnicas de Cocultura , Regulação da Expressão Gênica , Humanos , Queratinócitos/citologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação , Lentigo/prevenção & controle , Melanócitos/citologia , Melanócitos/metabolismo , Melanócitos/efeitos da radiação , Modelos Biológicos , Extratos Vegetais/química , Substâncias Protetoras/isolamento & purificação , Transdução de Sinais , Raios Ultravioleta/efeitos adversos , Proteína Wnt1/antagonistas & inibidores , Proteína Wnt1/metabolismoRESUMO
BACKGROUND: Exposure of the skin to solar ultraviolet (UV) radiations causes important oxidative damages that result in clinical and hystopathological changes, contributing to premature skin aging. Hyperpigmented lesions, also known as age spots, are one of the most visible alterations in skin photoaging. Skin is naturally equipped with antioxidant systems against UV-induced ROS generation; however, these antioxidant defenses are not completely efficient during exposure to sunlight. Oral antioxidants are able to counteract the harmful effects of UV radiation and to strengthen the physiological skin antioxidant defenses. AIMS: The present study was performed to evaluate the in vivo skin photo-protecting and anti-aging effects of a red orange (Citrus sinensis varieties Moro, Tarocco and Sanguinello) extract supplementation. Previous studies showed that red orange extracts possess strong in vitro free radical scavenging/antioxidant activity and photo-protective effects on human skin. MATERIALS/METHODS: The photo-protective effects of red orange extract intake against UV-induced skin erythema and melanin production in solar lentigo was evaluated on healthy volunteers by an objective instrumental method (reflectance spectrophotometry). RESULTS: Data obtained from in vivo studies showed that supplementation of red orange extract (100 mg/daily) for 15 days brought a significant reduction in the UV-induced skin erythema degree. Moreover, skin age spots pigmentation (melanin content) decreased from 27% to 7% when subjects were exposed to solar lamp during red orange extract supplementation. CONCLUSIONS: Red orange extract intake can strengthen physiological antioxidant skin defenses, protecting skin from the damaging processes involved in photo-aging and leading to an improvement in skin appearance and pigmentation.
Assuntos
Antioxidantes/uso terapêutico , Citrus sinensis , Lentigo/prevenção & controle , Extratos Vegetais/uso terapêutico , Lesões por Radiação/prevenção & controle , Envelhecimento da Pele/efeitos dos fármacos , Pele/efeitos dos fármacos , Adulto , Suplementos Nutricionais , Eritema/etiologia , Eritema/prevenção & controle , Humanos , Lentigo/etiologia , Lentigo/metabolismo , Melaninas/biossíntese , Pessoa de Meia-Idade , Fitoterapia , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversosRESUMO
Bath PUVA is a variant of phototherapy as efficacious as oral PUVA therapy that avoids many of the adverse effects associated to this treatment. Nevertheless, the special features and the specialized equipment required for its employment have limited its application in the dermatologic clinics of our country. Following the trend initiated after the publication of the consensus document on oral PUVA therapy and narrow band (NB) UVB therapy, the Spanish Photobiology Group from the Spanish Academy of Dermatology and Venereology has developed a therapeutic guideline for bath PUVA therapy based on the literature review and the experience of its members. The document aims to be a practical reference guide for those dermatological centres that include phototherapy among their services. It reviews the concept and indications of this type of treatment and proposes recommendations concerning therapeutic procedures, drug associations of interest and prophylaxis and management of adverse effects.