RESUMEN
OBJECTIVE: To investigate the safety and efficacy of resveratrol microemulsion gel in improving pigmentation. METHODS: Resveratrol microemulsion gel was prepared by the microemulsion solubilization method, and its quality was evaluated. The transdermal and drug retention rates of resveratrol in vivo were assessed using a transdermal test. The inhibitory effects of resveratrol suspension and microemulsion on tyrosinase activity and melanin production of A375 human melanocytes and zebrafish embryos were compared. A skin patch test was used to investigate the safety of the gel on 15 volunteers. RESULTS: The microemulsion gel was homogeneous and stable. Compared with suspension and microemulsion, the drug penetration rate and skin retention in the microemulsion gel group were significantly increased. Compared with the suspension group, the activity of melanocyte tyrosinase in A375 human melanocyte was significantly inhibited in the microemulsion group, and the melanin production rate of A375 human melanocyte and the melanin area of zebrafish yolk was decreased. All 15 volunteers tested negative for the human skin patch. CONCLUSIONS: The microemulsion gel could significantly enhance the ability of resveratrol to inhibit the formation of melanin without causing side effects. These data provide the experimental basis for developing and applying the preparation for improving pigmentation.
Asunto(s)
Absorción Cutánea , Pez Cebra , Animales , Humanos , Resveratrol , Pigmentación de la Piel , Melaninas/metabolismo , Monofenol Monooxigenasa/metabolismo , Aceite de Ricino/metabolismo , Piel/metabolismo , Polietilenglicoles/metabolismo , Emulsiones/metabolismoRESUMEN
The purpose of this study was to develop oil-in-oil-emulsions that facilitate long-term treatment for chronic pruritus with capsaicinoids. To this end, oil-in-oil-emulsions, which comprised polydimethyl siloxanes, silicone surfactant and castor oil, were examined. We used nonivamide, a synthetic analogue of capsaicin as the active pharmaceutical ingredient. It was incorporated into castor oil that formed the dispersed phase of the emulsion. We evaluated the influence of formulation variables (nonivamide content, phase volume ratio and viscosity of the silicone oil) on the in vitro release and the permeation of nonivamide. Permeation was found to be controlled by the nonivamide concentration in the dispersed phase and the phase volume ratio. Oil-in-oil-emulsions were found to produce constant permeation rates over a period of 10h. They are thus superior to conventional semisolid formulations as application intervals may be extended.
Asunto(s)
Capsaicina/análogos & derivados , Emulsiones/metabolismo , Aceites/metabolismo , Piel/metabolismo , Animales , Capsaicina/química , Capsaicina/metabolismo , Aceite de Ricino/química , Aceite de Ricino/metabolismo , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/metabolismo , Emulsiones/química , Aceites/química , Permeabilidad , Siliconas/química , Siliconas/metabolismo , Absorción Cutánea , Tensoactivos/química , Tensoactivos/metabolismo , PorcinosRESUMEN
Biocompatible and biodegradable polyurethanes (PUs) based on castor oil and polypropylene glycols (PPGs) were prepared using various carbohydrate crosslinkers: monosaccharide (glucose), disaccharide (sucrose) and polysaccharides (starch and cellulose). The mechanical and thermal properties were investigated and interpreted on the basis of SEM study. The advantage of incorporating various carbohydrates is to have tunable mechanical properties and biodegradability due to variety in their structure. The glass transition temperature and sorption behavior were dominated by the type of polyol than by the type of crosslinker. All the PUs were observed to be biodegradable as well as non-cytotoxic as revealed by MTT assay in normal lung cell line L132. The study supports the suitability of carbohydrates as important components of biocompatible PUs for development of biomedical devices.
Asunto(s)
Materiales Biocompatibles/química , Carbohidratos/química , Reactivos de Enlaces Cruzados/química , Poliuretanos/química , Materiales Biocompatibles/metabolismo , Metabolismo de los Hidratos de Carbono , Aceite de Ricino/química , Aceite de Ricino/metabolismo , Línea Celular , Supervivencia Celular , Reactivos de Enlaces Cruzados/metabolismo , Glucosa/química , Glucosa/metabolismo , Humanos , Ensayo de Materiales , Polímeros/química , Polímeros/metabolismo , Poliuretanos/metabolismo , Glicoles de Propileno/química , Glicoles de Propileno/metabolismo , Sacarosa/química , Sacarosa/metabolismo , Temperatura de TransiciónRESUMEN
Poly(hydroxyalkanoates) (PHAs) were isolated from Pseudomonas aeruginosa 44T1 cultivated on euphorbia oil and castor oil. With the aid of 2-D proton NMR spectra and proton-detected multiple bond coherence NMR spectra the structures of the PHAs were determined. In addition to the usual PHA constituents (C6-C14 3-hydroxy fatty acids), PHAs formed from euphorbia oil contained delta 8,9-epoxy-3-hydroxy-5c-tetradecenoate, and probably delta 6,7-epoxy-3-hydroxydodecanoate and delta 4,5-epoxy-3-hydroxydecanoate. These novel constituents account for approximately 15% of the total amount of monomers and are clearly generated via beta-oxidation of vernolic acid (delta 12,13-epoxy-9c-octadecenoic acid), the main component of euphorbia oil. In PHAs formed from castor oil, 7% of the monomers found were derived from ricinoleic acid (12-hydroxy-9c-octadecenoic acid). The presence of 3,8-dihydroxy-5c-tetradecenoate was clearly demonstrated. Furthermore, NMR analysis strongly suggested the presence of 3,6-dihydroxydodecanoate, 6-hydroxy-3c-dodecenoate, and 4-hydroxydecanoate.