29 research outputs found

    Caracterización farmacológica del efecto vasodilatador de extractos de bayas de calafate y de sus tres principales antocianinas glicosiladas

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    Calafate (Berberis microphylla) es una planta nativa de la Patagonia de Chile y Argentina, sus bayas son de color púrpura oscuro y posee la mayor capacidad antioxidante entre frutas comerciales y endémicas de Chile. Las bayas tienen alto contenido de compuestos fenólicos que incluyen varias antocianinas, flavonoles y ácidos fenólicos. Dado que la etnomedicina une las bayas chilenas con un efecto clínico benéfico, propusimos que los extractos de bayas de calafate tienen propiedades vasodilatadoras relacionadas a la variada naturaleza de sus compuestos. Con este propósito, extractos hidroalcohólicos de calafate (0.1-300 μg/mL) y 3 principales antocianinas glicosiladas (1nM-10 μM), fueron evaluadas en la red vascular mesentérica de rata previa contracción con noradrenalina, se determinó la dependencia del endotelio y producción de óxido nítrico. Extractos de calafate inducen una respuesta dilatadora concentración-dependiente (EC50 3.7 μg/mL); la respuesta máxima de vasodilatación (75-80%) se alcanzó con 10-30 μg/mL. La vasodilatación fue significativamente reducida por la remoción del endotelio (saponina 0.1%) (70 a 30%) e inhibición de eNOS con 150 μM de L-NNA (70 a 10%). El perfil químico del extracto (HPLC-ESI-MS/MS) identificó delfinidina (D3G), petunidina y malvidina como 3-glucósidos, las principales antocianinas del extracto. Las 3 antocianinas provocaron una relajación vascular endotelio-dependiente con diferente potencia y similar eficacia (40-50%). La principal antocianina D3G es más potente pero menos efectiva que los extractos de calafate, lo cual explica parcialmente que otros compuestos no antocianos del extracto enmascaran la respuesta inducida por D3G pero incrementan la eficacia del extractoFil: Calfío, C.. Universidad de Santiago de Chile.Fil: Huidobro-Toro, JP. Universidad de Santiago de Chile

    An adaptogenic role for omega-3 fatty acids in stress; a randomised placebo controlled double blind intervention study (pilot) [ISRCTN22569553]

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    BACKGROUND: There is evidence for an adaptive role of the omega -3 fatty acid, docosahexaenoic acid (DHA) during stress. Mechanisms of action may involve regulation of stress mediators, such as the catecholamines and proinflammatory cytokines. Prevention of stress-induced aggression and hostility were demonstrated in a series of clinical trials. This study investigates whether perceived stress is ameliorated by DHA in stressed university staff. METHODS: Subjects that scored ≥ 17 on the Perceived Stress Scale were randomised into a 6-week pilot intervention study. The diet reactive group was supplemented with 6 g of fish oil containing 1.5 g per day DHA, while the placebo group was supplemented with 6 g a day of olive oil. The groups were compared with each other and a wider cross sectional study population that did not receive either active or placebo intervention. RESULTS: There was a significant reduction in perceived stress in both the fish oil and the placebo group from baseline. There was also a significant between-group difference between the fish oil group and the no-treatment controls in the rate of stress reduction (p < 0.05). However, there was not a significant between-group difference between the fish oil and the placebo group, nor the placebo group and the control group. These results are discussed in the context of several methodological limitations. The significant stress reductions in both the fish oil and the placebo group are considered in view of statistical regression, an effect likely to have been exaggerated by the time course of the study, a large placebo effect and the possibility of an active effect from the placebo. CONCLUSION: There were significant differences (p < 0.05) in the fish oil group compared with no-treatment controls. This effect was not demonstrated in the placebo group. As a pilot study, it was not sufficiently powered to find the difference between the fish oil group and the placebo group significant. Further work needs to be undertaken to conclusively demonstrate these data trends. However, the findings from this research support the literature in finding a protective or 'adaptogenic' role for omega-3 fatty acids in stress
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