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1.
Front Immunol ; 11: 620098, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33658996

RESUMEN

The goal of this study was to elucidate the anti-pruritic and anti-inflammatory efficacy of ruxolitinib cream in experimentally-induced dermatitis. Atopic dermatitis (AD), the most common chronic relapsing inflammatory skin disease, significantly impairs patients' quality of life, with pruritus being a common complaint. The sensation of itch results from the interplay between epidermal barrier dysfunction, upregulated immune signaling and the activation of the central nervous system. The Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway plays a central role in pro-inflammatory cytokine signaling in AD. Ruxolitinib cream is a potent and selective JAK1/2 inhibitor currently undergoing clinical evaluation in adults with mild-to-moderate AD (NCT03745638, NCT03920852 and NCT03745651). The efficacy of ruxolitinib cream was tested in murine models of acute and chronic dermatitis and was also characterized in an ex vivo human skin dermatitis model. Ruxolitinib cream was highly effective at ameliorating disease symptoms in multiple murine dermatitis models through downregulation of T helper (Th)2-driven inflammation, resulting in reduced skin thickening and decreased itch. Pathway analysis of mouse ear tissue and human skin explants underscored the role for ruxolitinib in ameliorating inflammation and reducing itch via modulation of the JAK-STAT pathway. Together, the data offer a strong rationale for the use of ruxolitinib cream as a potent therapeutic agent for the clinical management of atopic dermatitis.


Asunto(s)
Dermatitis/tratamiento farmacológico , Inhibidores de las Cinasas Janus/uso terapéutico , Prurito/tratamiento farmacológico , Pirazoles/uso terapéutico , Administración Cutánea , Animales , Betametasona/administración & dosificación , Betametasona/uso terapéutico , Clobetasol/administración & dosificación , Clobetasol/uso terapéutico , Citocinas/biosíntesis , Citocinas/genética , Citocinas/toxicidad , Modelos Animales de Enfermedad , Erupciones por Medicamentos/tratamiento farmacológico , Erupciones por Medicamentos/inmunología , Evaluación Preclínica de Medicamentos , Femenino , Fluoresceína-5-Isotiocianato/toxicidad , Aseo Animal/efectos de los fármacos , Humanos , Técnicas In Vitro , Interleucina-33/genética , Inhibidores de las Cinasas Janus/administración & dosificación , Subgrupos Linfocitarios/efectos de los fármacos , Subgrupos Linfocitarios/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Nitrilos , Pomadas , Técnicas de Cultivo de Órganos , Pirazoles/administración & dosificación , Pirimidinas , Distribución Aleatoria , Transducción de Señal/efectos de los fármacos , Piel/efectos de los fármacos , Organismos Libres de Patógenos Específicos , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Linfocitos T Colaboradores-Inductores/inmunología , Transcriptoma , Linfopoyetina del Estroma Tímico
2.
Molecules ; 24(24)2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-31847298

RESUMEN

Producing wines within an acceptable range of astringency is important for quality and consumer acceptance. Astringency can be modified by fining during the winemaking process and the use of vegetable proteins (especially potato proteins) as fining agents has gained increasing interest due to consumers' requirements. The research presented was the first to investigate the effect of a potato protein dose on the kinetics of tannin and phenolic removal compared to gelatin for two unfined Cabernet Sauvignon wines. To further understand the results, the influence of the wine matrix and fining parameters (including pH, ethanol concentration, sugar concentration, temperature, and agitation) were tested according to a fractional 25-1 factorial design on one of the Cabernet Sauvignon wines using potato proteins. The results from the factorial design indicate that potato protein fining was significantly influenced by wine pH, ethanol concentration, fining temperature as well as an interaction (pH × ethanol) but not by sugar content or agitation. Insights into the steps required for the optimisation of fining were gained from the study, revealing that potato protein fining efficiency could be increased by treating wines at higher temperatures (20 °C, rather than the conventional 10-15 °C), and at both a lower pH and/or alcohol concentration.


Asunto(s)
Proteínas de Vegetales Comestibles/metabolismo , Solanum tuberosum/metabolismo , Vino/análisis , Cromatografía en Gel , Gelatina/análisis , Concentración de Iones de Hidrógeno , Cinética , Fenoles/análisis , Azúcares/análisis , Taninos/análisis
3.
J Agric Food Chem ; 67(32): 8938-8949, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31361121

RESUMEN

Polymeric pigments formed via ethyl linkages between grape tannins and anthocyanins are important to the development of stable red wine color. To determine the effect of tannin structure on the stability and color properties of ethyl-linked polymeric pigments, tannin fractions with average polymerization between 4 and 43 units were prepared from grape skins and seeds and combined with malvidin-3-glucoside (M3G) in model wine containing acetaldehyde. As tannin molecular mass increased, the reaction rate with M3G increased. Compared with skin tannins of comparable molecular mass, seed tannins reacted more rapidly with M3G but were prone to precipitation. This resulted in a loss of polymeric pigments formed from seed tannins, which was greater as tannin molecular mass increased. Aggregation occurred following the reaction of seed tannin with M3G, concomitant with precipitation. The aggregation-precipitation phenomenon was not observed for skin tannin-derived pigments, indicating a greater stability in solution than those formed from seed tannins.


Asunto(s)
Acetaldehído/química , Antocianinas/química , Pigmentos Biológicos/química , Extractos Vegetales/química , Semillas/química , Taninos/química , Vitis/química , Precipitación Química , Color , Frutas/química , Cinética , Peso Molecular , Polimerizacion , Polímeros/química
4.
Molecules ; 23(7)2018 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-30037004

RESUMEN

Ruminants produce large amounts of the greenhouse gas, methane, which can be reduced by supplementing feed with products that contain anti-methanogenic compounds, such as the solid winemaking by-product, grape marc. The aim of this study was to exploit compositional differences in grape marc to better understand the roles of condensed tannin and fatty acids in altering methanogenesis in a ruminant system. Grape marc samples varying in tannin extractability, tannin size and subunit composition, and fatty acid or tannin concentrations were selected and incubated in rumen fluid using an in vitro batch fermentation approach with a concentrate-based control. Four distinct experiments were designed to investigate the effects on overall fermentation and methane production. Generally, fatty acid concentration in grape marc was associated with decreased total gas volumes and volatile fatty acid concentration, whereas increased condensed tannin concentration tended to decrease methane percentage. Smaller, extractable tannin was more effective at reducing methane production, without decreasing overall gas production. In conclusion, fatty acids and tannin concentration, and tannin structure in grape marc play a significant role in the anti-methanogenic effect of this by-product when studied in vitro. These results should be considered when developing strategies to reduce methane in ruminants by feeding grape marc.


Asunto(s)
Ácidos Grasos , Metano/biosíntesis , Taninos , Vitis/química , Alimentación Animal , Animales , Ácidos Grasos/química , Fermentación , Polimerizacion , Rumiantes , Taninos/química
5.
J Agric Food Chem ; 64(44): 8406-8419, 2016 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-27616021

RESUMEN

For better understanding of the factors that impact proanthocyanidin (PA) adsorption by insoluble cell walls or interaction with soluble cell wall-derived components, application of a commercial polygalacturonase enzyme preparation was investigated to modify grape cell wall structure. Soluble and insoluble cell wall material was isolated from the skin and mesocarp components of Vitis vinifera Shiraz grapes. It was observed that significant depolymerization of the insoluble grape cell wall occurred following enzyme application to both grape cell wall fractions, with increased solubilization of rhamnogalacturonan-enriched, low molecular weight polysaccharides. However, in the case of grape mesocarp, the solubilization of protein from cell walls (in buffer) was significant and increased only slightly by the enzyme treatment. Enzyme treatment significantly reduced the adsorption of PA by insoluble cell walls, but this effect was observed only when material solubilized from grape cell walls had been removed. The loss of PA through interaction with the soluble cell wall fraction was observed to be greater for mesocarp than skin cell walls. Subsequent experiments on the soluble mesocarp cell wall fraction confirmed a role for protein in the precipitation of PA. This identified a potential mechanism by which extracted grape PA may be lost from wine during vinification, as a precipitate with solubilized grape mesocarp proteins. Although protein was a minor component in terms of total concentration, losses of PA via precipitation with proteins were in the order of 50% of available PA. PA-induced precipitation could proceed until all protein was removed from solution and may account for the very low levels of residual protein observed in red wines. The results point to a dynamic interaction of grape insoluble and soluble components in modulating PA retention in wine.


Asunto(s)
Pared Celular/química , Proantocianidinas/química , Vitis/citología , Vino , Tampones (Química) , Precipitación Química , Enzimas/química , Enzimas/metabolismo , Peso Molecular , Monosacáridos/análisis , Pectinas/química , Polisacáridos/química , Solubilidad , Soluciones/química , Vitis/química
6.
J Agric Food Chem ; 63(45): 9954-62, 2015 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-26551987

RESUMEN

To determine the optimum methods for determining condensed tannin (CT) content in grape marc, butanol-hydrochloric acid assays and phloroglucinolysis were adapted for use, applied to a range of grape marc types, and the methods compared. Porter's assay (butanol-HCl) was found to give unreliable results due to nonlinear color responses to grape skin and seed tannin concentrations, whereas the modification to include acetone (Grabber's assay) overcame this. Differences between skin and seed tannin responses highlighted the need to adequately select the correct grape tannin standard, and the formation of pH-dependent color was accounted for through acidification of blank samples. For phloroglucinolysis, the inability to remove highly bound tannins from cell wall material was highlighted, although a measure of tannins remaining post-phloroglucinolysis (Grabber's assay) showed a trend with the level of exposure to oxidative storage or processing conditions. The comparison of CT concentrations from phloroglucinolysis and Grabber's assay gave poor correlation coefficients.


Asunto(s)
Técnicas de Química Analítica/métodos , Floroglucinol/química , Extractos Vegetales/química , Proantocianidinas/química , Vitis/química , Residuos/análisis , Polimerizacion , Semillas/química
7.
Biochem Biophys Res Commun ; 460(3): 857-62, 2015 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-25824037

RESUMEN

Antipsychotics (APs) are widely used medications, however these are not without side effects such as disruption of blood brain barrier function (BBB). To investigate this further we have studied the chronic effects of the typical APs, chlorpromazine (CPZ) and haloperidol (HAL) and the atypical APs, risperidone (RIS) and clozapine (CLZ), on the bioenergetics of human micro-vascular endothelial cells (HBVECs) of the BBB. Alamar blue (AB) and ATP assays showed that these APs impair bioenergenesis in HBVECs in a concentration and time dependent manner. However since these effects were incomplete they suggest a population of cell bioenergetically heterogeneous, an idea supported by the bistable nature by which APs affected the mitochondrial transmembrane potential. CPZ, HAL and CLZ inhibited the activity of mitochondrial complexes I and III. Our data demonstrates that at therapeutic concentrations, APs can impair the bioenergetic status of HBVECs, an action that help explains the adverse side effects of these drugs when used clinically.


Asunto(s)
Antipsicóticos/farmacología , Endotelio Vascular/efectos de los fármacos , Metabolismo Energético , Células Cultivadas , Endotelio Vascular/citología , Endotelio Vascular/metabolismo , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos
8.
Carbohydr Polym ; 114: 102-114, 2014 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-25263870

RESUMEN

Cell wall material was isolated from two Vitis vinifera grape varieties, Cabernet Sauvignon and Shiraz, following a buffered phenol extraction method. Using sequential fractionation in chelating agent, then increasing the molarity of aqueous potassium hydroxide, polysaccharide classes were selectively extracted from cell walls to produce fractions of defined polysaccharide composition. Following the application of phloroglucinolysis and a modified HCl-butanol colourimetric assay to cell wall fractions, more than 54% of cell wall-bound proanthocyanidin was localised within the chelator-soluble (pectic) fraction. Model adsorption experiments with a purified skin proanthocyanidin confirmed that the removal of pectic polysaccharides by chelator most significantly reduced the adsorption of proanthocyanidin by cell walls. Nevertheless, cell wall hemicellulosic fractions retained a high binding capacity for proanthocyanidin, although lower than that observed when pectin was present. Following removal of hemicelluloses by fractionation, the primarily lignocellulosic residue had a significantly reduced affinity for proanthocyanidin. With the exception of lignocellulose, a greater selectivity of adsorption for higher molecular mass proanthocyanidins was observed by the respective cell wall fractions.


Asunto(s)
Pared Celular , Extractos Vegetales/aislamiento & purificación , Polisacáridos/aislamiento & purificación , Proantocianidinas/aislamiento & purificación , Vitis , Adsorción/fisiología , Pared Celular/metabolismo , Carbohidratos de la Dieta/aislamiento & purificación , Carbohidratos de la Dieta/metabolismo , Extractos Vegetales/metabolismo , Polisacáridos/metabolismo , Proantocianidinas/metabolismo
9.
J Agric Food Chem ; 62(41): 10008-14, 2014 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-25248855

RESUMEN

The juice used to make white wine can be extracted using various physical processes that affect the amount and timing of contact of juice with skins. The influence of juice extraction processes on the mouthfeel and taste of white wine and their relationship to wine composition were determined. The amount and type of interaction of juice with skins affected both wine total phenolic concentration and phenolic composition. Wine pH strongly influenced perceived viscosity, astringency/drying, and acidity. Despite a 5-fold variation in total phenolics among wines, differences in bitter taste were small. Perceived viscosity was associated with higher phenolics but was not associated with either glycerol or polysaccharide concentration. Bitterness may be reduced by using juice extraction and handling processes that minimize phenolic concentration, but lowering phenolic concentration may also result in wines of lower perceived viscosity.


Asunto(s)
Preparaciones de Plantas/química , Gusto , Vitis/química , Vino/análisis , Adulto , Bebidas/análisis , Femenino , Manipulación de Alimentos , Humanos , Masculino , Fenoles/análisis , Preparaciones de Plantas/aislamiento & purificación
10.
J Agric Food Chem ; 62(5): 1130-41, 2014 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-24432763

RESUMEN

The acetone-extractable (70% v/v) skin tannin content of Vitis vinifera L. cv. Cabernet Sauvignon grapes was found to increase during late-stage ripening. Conversely, skin tannin content determined following ethanol extraction (10, 20, and 50% v/v) did not consistently reflect this trend. The results indicated that a fraction of tannin became less extractable in aqueous ethanol during ripening. Skin cell walls were observed to become more porous during ripening, which may facilitate the sequestering of tannin as an adsorbed fraction within cell walls. For ethanol extracts, tannin molecular mass increased with advancing ripeness, even when extractable tannin content was constant, but this effect was negligible in acetone extracts. Reconstitution experiments with isolated skin tannin and cell wall material indicated that the selectivity of tannin adsorption by cell walls changed as tannin concentration increased. Tannin concentration, tannin molecular mass, and cell wall porosity are discussed as factors that may influence skin tannin extractability.


Asunto(s)
Frutas/crecimiento & desarrollo , Extractos Vegetales/aislamiento & purificación , Taninos/aislamiento & purificación , Vitis/química , Pared Celular/química , Frutas/química , Extractos Vegetales/análisis , Taninos/análisis , Vitis/crecimiento & desarrollo
11.
World J Gastroenterol ; 14(27): 4420-3, 2008 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-18666339

RESUMEN

Nutritional therapy for active Crohn's disease (CD) is an underutilised form of treatment in adult patients, though its use is common in the paediatric population. There is evidence that nutritional therapy can effectively induce remission of CD in adult patients. Enteral nutrition therapy is safe and generally well tolerated. Meta-analysis data suggest that corticosteroids are superior to nutritional treatment for induction of remission in active CD. However, the potential side effects of such pharmacotherapy must be taken into consideration. This review examines the evidence for the efficacy of elemental and polymeric diets, and the use of total parenteral nutrition in active CD.


Asunto(s)
Corticoesteroides/farmacología , Enfermedad de Crohn/dietoterapia , Terapia Nutricional , Ensayos Clínicos como Asunto , Enfermedad de Crohn/terapia , Humanos , Ciencias de la Nutrición , Inducción de Remisión , Esteroides/uso terapéutico , Resultado del Tratamiento
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