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1.
Int J Cosmet Sci ; 42(5): 444-451, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32583541

RESUMEN

BACKGROUND: The loss of structural elastin due to intrinsic and extrinsic ageing results in the skin's inability to stretch and recoil (decrease in elasticity) and manifests as loss of skin firmness and sagging. While other extracellular matrix (ECM) components such as collagen and hyaluronic acid are continually synthesized and assembled through life, elastic fibres are not. Elastic fibre assembly and functionality require fibre cross-linking, induced by the lysyl oxidase-like (LOXL) enzymes, which sharply decrease during ageing. OBJECTIVE: To evaluate the enhanced elastogenic effect of a blackberry-dill extract combination, which was hypothesized to induce elastin fibre component synthesis, fibre cross-linking and reduce elastin fibre degradation. METHODS: The blackberry and the dill extracts were tested separately and in combination to confirm single ingredient bioactivity and synergistic benefits. Human skin explants, dermal fibroblasts, elastase assays, ELISAs, quantitative real-time PCRs and spectrofluorometer measurements were used. Moreover, a double-blinded, placebo-controlled clinical study was carried out to assess skin elasticity using Cutometer and histologically from biopsies. RESULTS: The blackberry extract induced elastin gene expression, elastin promoter activity and inhibited elastic fibre degradation by matrix metalloproteinases (MMPs) 9 and 12. The dill extract induced elastin, collagen and LOXL1 gene expression, resulting in enhanced fibre cross-linking in human skin explants. Clinically, the blackberry and dill combination treatment displayed synergistic pro-elasticity activity as compared to each ingredient alone and placebo. CONCLUSION: Taken together, these results demonstrated the two multimodal plant-based extracts complemented each other in terms of bioactivity and resulted in a synergistic elastogenesis induction.


CONTEXTE: la perte de l'élastine structurelle causée par un vieillissement intrinsèque et extrinsèque provoque l'incapacité de la peau à s'étirer et à rebondir (diminution de l'élasticité) et se manifeste comme une perte de fermeté et un relâchement de la peau. Alors que d'autres composants de la matrice extracellulaire (MEC), tels que le collagène et l'acide hyaluronique sont continuellement synthétisés et assemblés tout au long de la vie, les fibres élastiques ne le sont pas. L'assemblage et la fonctionnalité des fibres élastiques nécessitent une réticulation des fibres, causée par les enzymes de type lysyle oxydase (LOXL), qui diminuent fortement au cours du vieillissement. OBJECTIF: évaluer l'effet élastogène amélioré d'une combinaison d'extrait de mûre et d'aneth, qui était supposée induire la synthèse des composants des fibres d'élastine, la réticulation des fibres et réduire la dégradation des fibres d'élastine. MÉTHODES: les extraits de mûre et d'aneth ont été testés séparément et ensemble pour confirmer la bioactivité d'un seul ingrédient et les avantages synergiques. Des explants de peau humaine, des fibroblastes cutanés, des dosages d'élastase, des ELISA, des analyses PCR quantitatives en temps réel et des mesures de spectrofluorimètre ont été utilisés. De plus, une étude clinique en double aveugle, contrôlée par placebo, a été réalisée pour évaluer l'élasticité de la peau à l'aide du cutomètre et histologiquement à partir de biopsies. RÉSULTATS: l'extrait de mûre a induit l'expression génique de l'élastine, l'activité de promoteur de l'élastine et a inhibé la dégradation des fibres élastiques par des métalloprotéinases matricielles (MPM) 9 et 12.L'extrait d'aneth a causé l'expression génique de l'élastine, du collagène et du gène LOXL1, entraînant une amélioration de la réticulation des fibres dans les explants de peau humaine. Cliniquement, le traitement par une combinaison de mûre et d'aneth a montré une activité de pro-élasticité synergique par rapport à chaque ingrédient seul et au placebo. CONCLUSION: ensemble, ces résultats ont démontré que les deux extraits de plantes multimodales se complètent en termes de bioactivité et ont entraîné une induction synergique de l'élastogenèse.


Asunto(s)
Anethum graveolens/química , Elasticidad , Extractos Vegetales/farmacología , Rubus/química , Piel/efectos de los fármacos , Animales , Método Doble Ciego , Sinergismo Farmacológico , Elastina/metabolismo , Matriz Extracelular/metabolismo , Humanos , Ratas , Piel/metabolismo , Espectrometría de Fluorescencia
2.
Br J Dermatol ; 173(1): 218-26, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25752195

RESUMEN

BACKGROUND: The nuclear factor-κB (NF-κB) pathway is a key mediator of inflammation; however, few studies have examined the direct effects of NF-κB inhibition on the skin. OBJECTIVES: To investigate NF-κB activity in cultured human fibroblasts and to investigate the effects of 4-hexyl-1,3-phenylenediol (an NF-κB inhibitor) on elastin and collagen gene expression in vitro and on the clinical appearance of photodamaged skin. METHODS: The amount and activity of NF-κB in human fibroblasts obtained from donors (17-78 years old) was measured after transfection with a NF-κB reporter and a luciferase promoter system. The expression of extracellular matrix (ECM) genes was determined using quantitative polymerase chain reaction. Women with moderate skin photodamage were randomized to daily treatment with a topical lotion containing 4-hexyl-1,3-phenylenediol (n = 30) or vehicle (n = 29) for 8 weeks, with clinical assessments at baseline and weeks 2, 4 and 8. RESULTS: Fibroblasts obtained from donors older than 50 years had higher NF-κB activity compared with cells from younger donors; inhibition of the NF-κB pathway with 4-hexyl-1,3-phenylenediol enhanced the expression of ECM genes. In women, treatment for 8 weeks with 4-hexyl-1,3-phenylenediol significantly improved crow's feet fine lines, cheek wrinkles, age spots, mottled pigmentation and radiance compared with both the vehicle and baseline. Furthermore, treatment with 4-hexyl-1,3-phenylenediol resulted in a twofold greater clinical improvement in overall photodamage compared with the vehicle group. CONCLUSIONS: Inhibition of the proinflammatory NF-κB pathway resulted in increased expression of ECM proteins in vitro and significant clinical improvement in photodamaged skin.


Asunto(s)
Fármacos Dermatológicos/administración & dosificación , Dermatosis Facial/tratamiento farmacológico , FN-kappa B/antagonistas & inhibidores , Trastornos por Fotosensibilidad/tratamiento farmacológico , Resorcinoles/administración & dosificación , Envejecimiento de la Piel/efectos de los fármacos , Adolescente , Adulto , Anciano , Células Cultivadas , Colágeno Tipo I/metabolismo , Método Doble Ciego , Ensayo de Inmunoadsorción Enzimática , Femenino , Fibroblastos/efectos de los fármacos , Humanos , Técnicas In Vitro , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
3.
J Invest Dermatol ; 119(6): 1330-40, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12485436

RESUMEN

The microphthalmia-associated transcription factor is implicated in melanocyte development and in the regulation of melanogenesis. Microphthalmia-associated transcription factor is thought to bind to the M-box promoter elements of tyrosinase, tyrosinase-related protein-1 and dopachrome tautomerase/tyrosinase-related protein-2 and transactivate these genes, resulting in increased pigmentation. Using a luciferase reporter construct driven by the microphthalmia-associated transcription factor promoter, we identified agents that modulate microphthalmia-associated transcription factor promoter activity. Changes in endogenous microphthalmia-associated transcription factor expression levels upon treatment with these agents were confirmed using northern and western blots, and their pigmentary modulating activities were demonstrated. Ultraviolet B irradiation and traditional Chinese medicine-1, a natural extract used in traditional Chinese medicine, upregulated microphthalmia-associated transcription factor gene expression and enhanced tyrosinase activity in vitro. Dihydrolipoic acid, lipoic acid, and resveratrol reduced microphthalmia-associated transcription factor and tyrosinase promoter activities. These agents also inhibited the forskolin- and ultraviolet B-stimulated promoter activities of these genes and significantly reduced tyrosinase activity in melanocyte cultures, resulting in depigmentation. Overexpressed microphthalmia-associated transcription factor was capable of rescuing the repressive effects of these compounds on the cotransfected tyrosinase promoter. Dark-skinned Yucatan swine treated with these agents showed visible skin lightening, which was confirmed histologically, whereas ultraviolet B-induced tanning of light-skinned swine was inhibited using these agents. Our findings suggest that modulation of microphthalmia-associated transcription factor expression can alter skin pigmentation and further confirm the central role of microphthalmia-associated transcription factor in melanogenesis.


Asunto(s)
Proteínas de Unión al ADN/genética , Pigmentación de la Piel/fisiología , Factores de Transcripción/genética , Ácido 8,11,14-Eicosatrienoico/farmacología , Animales , Antioxidantes/farmacología , Células Cultivadas , Colforsina/farmacología , Medicamentos Herbarios Chinos/farmacología , Expresión Génica/efectos de los fármacos , Expresión Génica/efectos de la radiación , Humanos , Luciferasas/genética , Melanocitos/fisiología , Factor de Transcripción Asociado a Microftalmía , Monofenol Monooxigenasa/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos , Regiones Promotoras Genéticas/efectos de la radiación , Resveratrol , Pigmentación de la Piel/efectos de los fármacos , Pigmentación de la Piel/efectos de la radiación , Estilbenos/farmacología , Porcinos , Ácido Tióctico/farmacología , Rayos Ultravioleta
4.
Science ; 281(5383): 1666-8, 1998 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-9733511

RESUMEN

The gastric stomach of humans is a barrier to food-borne pathogens, but Escherichia coli can survive at pH 2.0 if it is grown under mildly acidic conditions. Cattle are a natural reservoir for pathogenic E. coli, and cattle fed mostly grain had lower colonic pH and more acid-resistant E. coli than cattle fed only hay. On the basis of numbers and survival after acid shock, cattle that were fed grain had 10(6)-fold more acid-resistant E. coli than cattle fed hay, but a brief period of hay feeding decreased the acid-resistant count substantially.


Asunto(s)
Alimentación Animal , Bovinos/microbiología , Colon/microbiología , Grano Comestible , Escherichia coli/crecimiento & desarrollo , Poaceae , Crianza de Animales Domésticos , Animales , Bacterias Anaerobias/crecimiento & desarrollo , Colon/química , Recuento de Colonia Microbiana , Medios de Cultivo , Dieta , Ácidos Grasos Volátiles/análisis , Concentración de Iones de Hidrógeno , Ácido Láctico/análisis , Distribución Aleatoria , Rumen/química , Rumen/microbiología , Succinatos/análisis
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