508 research outputs found
Aceite de oliva, clave de vida en la Cuenca Mediterránea
In this paper some historical aspects of olive oil are reviewed, as well as its cultural and nutritional importance. The different types of olive oil as their characteristics are described and their benefits discussed in the framework of the Mediterranean diet. Mediterranean Diet and frying are non separable concepts. In fact, this is a culinary technique extendedly employed in the Mediterranean Basin. Moreover, some advices are given to properly use the olive oil as fresh as in frying. Based on the low cardiovascular mortality found in the Mediterranean cohorts respect to other counterparts from different World parts, this diet has been proposed as a model to get a correct nutritional status and to get a significant protection against degenerative diseases very prevalent in Developed countries. The classical Mediterranean diet can be defined with a pyramidal structure based in vegetable foods, being obliged the inclusion of virgin olive oil as practically the only culinary food. Its also contains small amounts of foods from animal origin (mainly fish and dairy products). Wine daily consumed with moderation during meals is also one of its important characteristics. Such dietetic model implies the balance between energy income and expenditure. Beneficial effects of olive oils are discussed in three subsections focussing them on health aspects of great social and economical importance: Aging and longevity; cardiovascular disease and cancer. Such benefits have been attributed to its fatty acid composition, very rich in monounsaturated fatty acids, and moderate in saturate and polyunsaturated fatty acids. Furthermore, virgin olive oils contain antioxidant compounds and the polyunsaturated fatty acid/tocopherol ratio is more adequate to prevent from lipid oxidation than that of most consumed oils. In the virgin and extra virgin olive oils have been found and quantified biophenols with very important antioxidant properties and role in atherogenesis and cancer. Some recent papers and the proposed molecular mechanisms are also presented and discussed. The review ends concluding that consuming olive oil helps to get a more correct lipid profile and in line with very actual nutritional guidelines and recommendations.En este trabajo se revisan algunos aspectos históricos sobre el aceite de oliva, así como su importancia cultural y nutricional. Posteriormente, se definen los diferentes tipos de aceites de oliva y sus características principales y se discuten los beneficios del consumo de aceite de oliva virgen en el ámbito de la dieta mediterránea. Se insiste que no hay dieta mediterránea sin consumir alimentos fritos, ya que la fritura es una técnica muy extendida y muy utilizada en la Cuenca Mediterránea y se dan ciertos consejos sobre la utilización del aceite en crudo y en fritura. Basado en la baja mortalidad cardiovascular encontrada en países del Área Mediterránea respecto a poblaciones de otras latitudes, se señala que esta dieta ha sido propuesta como modelo a seguir para conseguir un estatus nutricional correcto y una adecuada protección contre enfermedades degenerativas muy prevalentes en las sociedades desarrolladas. La dieta mediterránea clásica se define con una estructura piramidal que está basada principalmente en alimentos vegetales, siendo obligado el consumo diario de aceite de oliva virgen, el cual es, con mucho, su principal fuente de grasa culinaria. Contiene además pequeñas cantidades de alimentos de origen animal (en forma de pescados y lácteos) y el consumo diario moderado de bebidas alcohólicas, principalmente en forma de vino tinto y consumido durante las comidas, es otra de sus características. Dicho modelo dietético implica equilibrio entre ingesta y gasto energético. Los efectos beneficiosos del aceite de oliva se tratan en extensión en tres subapartados donde se revisan sus acciones en aspectos de salud de gran importancia social y económica: Longevidad y supervivencia; enfermedad cardiovascular y cáncer. Tales beneficios se han atribuido a su composición en ácidos grasos, muy rico en ácidos grasos monoinsaturados y con una concentración moderada en ácidos grasos saturados y poliinsaturados. Además posee compuestos antioxidantes y la relación ácidos grasos poliinsaturados/tocoferoles es más adecuada que la de otros aceites para prevenir la oxidación lipídica. En los aceites de oliva virgen y virgen extra se han encontrado y cuantificado biofenoles con propiedades antioxidantes muy importantes y con papeles en la modulación de la aterogénesis y posiblemente en el cáncer. Se presentan y discuten algunos trabajos recientes donde se señalan posibles mecanismos de acción de estos compuestos. La revisión termina planteando que el consumo de aceite de oliva ayuda a alcanzar un perfil lipídico dietético más correcto y en línea con los objetivos y recomendaciones nutricionales actuales
Hypercortisolaemia and Hyperinsulinaemia Interaction and their Impact upon Insulin Resistance/Sensitivity Markers at Birth
Information on insulin resistance/sensitivity in term-normoweight neonates is scarce. The hypothalamus-pituitary-adrenal cortex axis and pancreas are implicated in several aspects of foetal maturation and programming. This study aims to analyse the effects of a combination of hyperinsulinaemia plus hypercortisolaemia in such neonates together with their mothers℉ gestational glucose tolerance on growth hormone (GH), insulin-like growth factor-1 (IGF)-1, glucose, and insulin resistance/sensitivity markers [homeostatic model assessment-insulin resistance (HOMA-IR)/quantitative insulin sensitivity check index (QUICKI)] at birth. Furthermore, the importance of pregnancy diet quality on these markers is discussed. In a selected group of 187 term-normoweight non-distressed neonates, about 9% had increased insulin and cortisol cord-blood concentrations. In spite of normality criteria applied, the combination of hypercortisolaemia and hyperinsulinaemia at birth was associated with higher body weight, body length, glucose, HOMA-IR, GH, IGF-1 and glucose/insulin ratio values than those of neonates presenting low/normal concentrations of insulin and cortisol. Hyperinsulinaemia preferentially to hypercortisolaemia affected the markers studied. Impaired glucose tolerance prevalence was higher in mothers whose neonates were hyperinsulinaemic at birth. The hyperinsulinaemic plus hypercortisolaemic status was more prevalent in neonates whose mothers had poor Mediterranean diet adherence. Results show the importance of analysing insulin and cortisol in cord-blood even in term-normoweight neonates
Iron Status Biomarkers and Cardiovascular Risk
Both iron excess and deficiency may be related to oxidative stress. Serum ferritin, the main marker of iron status, and hepcidin, the key regulator of iron metabolism, are increased in inflammation states and their links with insulin resistance are emerging topics. We have reviewed the role of iron deficiency/overload in cardiovascular risk, including our own results. Most studies deal with the association between iron deposition in tissues and cardiovascular risk, while decreased iron status is predominantly related to protection against atherosclerosis and coronary heart disease. Less information is available on the role of iron status in type 2 diabetes mellitus (T2DM). Serum ferritin is positively correlated with several indicators of cardiovascular risk in healthy adults and diabetics, thus excess body iron is related to cardiometabolic alterations including vascular and heart damage, central obesity, and metabolic syndrome. Our data in an ample sample of T2DM adults suggest that body iron stores, evaluated as ferritin, are clearly related with some key markers of the so-called lipidic triad (high triglyceride and low high-density lipoprotein (HDL) cholesterol) levels together with the presence of small and dense low-density lipoprotein particles which also is in the frame of the dysmetabolic iron overload syndrome
¿Es el consumo de carne y derivados peligroso para la salud? Relación con el riesgo de cáncer colorrectal y otras enfermedades degenerativas
The excessive intake of meat and meat products has been related with increased morbi-mortality incidence of chronic diseases, particularly with cardiovascular diseases and various types of cancer. Very recently the WHO has published a preliminary inform associating meat products consumption with colorectal cancer, suggesting that this association is based in the presence of different compounds (e.g. nitrites, nitrates) that are normally present in in those foods, especially in modified meat products that are suggested to culinary procedures. Nonetheless, although risk and alarm exist, several items pointed out in this inform has, to the best of our knowledge, limitations that we will try to indicate and review, particularly those of derived from observational studies where the cause-effect relationship found did not fit the criteria demanded By Hill for Epidemiological studies. Thus, present review discuses in the frame of the meat and meat products the following items: 1) definition; 2) consumption in Spain; 3) nutritional importance; 4) consumption health risks; 5) potential toxic products in meat products, the WHO inform; 6) other dietary compounds and their palliative role in the meat-pathology relationship; 7; the role and importance of the media in the news; 8) conclusions and future remarks.El consumo excesivo de carne y derivados ha sido relacionado con una incidencia incrementada de morbi-mortalidad por enfermedades degenerativas, particularmente con las enfermedades cardiovasculares y diferentes tipos de cáncer. Muy recientemente la OMS ha emitido un informe preliminar asociando consumo de carne y cáncer de colon, atribuyendo dicha relación a la presencia de diferentes tipos de compuestos (p.e. aminas aromáticas, nitritos, nitratos)presentes en este grupo de alimentos, especialmente en los cárnicos modificados y que pueden originarse por la manipulación culinaria. No obstante, y aunque la alarma y el riesgo existen, muchos aspectos señalados en ese informe tienen a nuestro entender limitaciones que pretendemos señalar y revisar, particularmente aquellas derivadas de estudios observacionales, donde la relación causa-efecto encontrada no cumple los criterios demandados por Hill para estudios epidemiológicos. Por ello la revisión analiza en el contexto de carne y productos cárnicos los siguientes apartados: 1) definición; 2) consumo en España; 3) importancia nutricional; 4) riesgos para la salud; 5) compuestos potencialmente tóxicos en carne y derivados, el informe de la OMS; 6) otros componentes de la dieta y su papel paliativo en la relación carne-patología; 7) el poder y la importancia de los medios en la comunicación de noticias; 8) conclusiones, pautas y actuaciones futuras
Metode i važnost ispitivanja oksidacije biljnih ulja, masti i lipoproteina pomoću lipaze pankreasa i arilesteraze
Fats and oils as major dietary components are involved in the development of chronic diseases. In this paper the physiological relevance and some methodological aspects related to the determination of two enzymes enrolled in metabolism of fat – pancreatic lipase and arylesterase – are discussed. Pancreatic lipase has been extensively used to study the triacylglycerol fatty acid composition and the in vitro digestion of oils and fats. The action of this enzyme may be coupled to analytical methods as GC, HPLC, HPSEC, TLC- -FID, etc. as a useful tool for understanding the composition and digestion of thermal oxidized oils. Pancreatic lipase hydrolysis occurs in the water/oil interface, and it presents a behaviour that seems to be Michaelian, in which the apparent Km and the apparent Vmax of the enzymatic process depend more on the type of oil tested than on the degree of alteration. The kinetic behaviour of pancreatic lipase towards thermally oxidized oils also depends on the presence of natural tensioactive compounds present in the oil and surfactants formed during the frying. Arylesterase is an HDL binding enzyme that inhibits LDL oxidation. Low serum concentration of this enzyme has been related to increased cardiovascular disease risk. In this paper the most widely used methods for the determination of arylesterase activity are commented on. The importance of intrinsic factors (e.g. substrates, cofactors) participating in the enzyme reaction is also discussed. Moreover, several suggestions about further researches on the influence of extrinsic factors (e.g. diet, oxidative stress) upon the enzyme activity are proposed.Masti i ulja, kao glavni sastojci prehrane, uzrok su razvoja nekih kroničnih bolesti. U radu su ispitivani fiziološka važnost i neke metode određivanja dvaju enzima koji sudjeluju u metabolizmu masti, i to lipaze pankreasa i arilesteraze. Lipaza pankreasa vrlo se često koristila u ispitivanju sastava masnih kiselina u triacilglicerolima i u in vitro digestiji ulja i masti. Djelovanje tog enzima može se povezati s analitičkim metodama kao što su GC, HPLC, HPSEC i TLC-FID kako bi se utvrdio sastav i digestija toplinski oksidiranih ulja. Hidrolitsko djelovanje lipaze pankreasa provodi se na granici faza voda/ulje, te se čini da se pokorava Michaelis-Mentenovoj kinetici, u kojoj prividne Km i Vmax vrijednosti enzimskog procesa više ovise o vrsti ispitivanog ulja nego o stupnju hidrolize. Kinetika lipaze pankreasa prema toplinski oksidiranim uljima ovisi također o prisutnosti prirodnih tenzioaktivnih spojeva u ulju i o površinski aktivnim spojevima nastalim tijekom prženja. Arilesteraza je enzim koji veže HDL i time inhibira oksidaciju LDL. Mala koncentracija tog enzima u serumu povezana je s povećanim rizikom kardiovaskularnih bolesti. U radu su prikazane najčešće primijenjeni postupci za određivanje aktivnosti arilesteraze. Ujedno je razmotrena važnost unutarnjih faktora (npr. supstrata, kofaktora) koji sudjeluju u enzimskoj reakciji. Nadalje, predložena su daljnja istraživanja o utjecaju vanjskih faktora (npr. dijeta, oksidativni stres) na aktivnost enzima
Dieta e hidratación en la prevención y tratamiento de la obesidad
Energy intake and expenditure balance is nowadays accepted to be a determinant factor on body composition. Thus, solid and liquid adequate consumption have enormous importance to prevent overweight and obesity. In addition, the dietotherapy is considered the obesity treatment cornerstone, being critical the adequacy of water and non-caloric liquid consumptions to the subject characteristics, physical activity and kind of treatment to be followed. In this paper the mechanisms involved in food and dipsic behaviours and orosensitive gratification, and the neural circuits involved are reviewed. Emphasis is given to the idea that diet importance is not restricted to its direct action on the incomes/outcomes balance but on the modulation that its compounds exert on intake regulation, gene expression, thermogenesis, lipogenesis/lipolysis, insulin resistance/sensitivity, and microbiota characteristics. Some central aspects of diet in childhood and adult obesity prevention and treatment are reviewed. The different types of treatments are commented under quantitative and qualitative points of view, together with the practical objective to define slimming rhythm and therapeutic final body weight. The paper ends pointing out to difficulties for maintain weight losses and the importance to design and follow an individual corrector treatment based on adequate and accurate diets to be consumed for a very long life period.En la actualidad se acepta que el balance entre la energía ingerida y el gasto calórico es un factor determinante de la composición corporal. Por ello, realizar una adecuada ingesta, tanto sólida como líquida, se considera de enorme importancia para prevenir el sobrepeso y la obesidad. A su vez, la dietoterapia constituye la piedra angular del tratamiento de la obesidad, debiendo adecuarse el consumo de agua y líquidos acalóricos a las características y actividad física del índividuo y al tipo de tratamiento. En esta publicación se revisan los mecanismos implicados en el comportamiento alimentario y dípsico, y en la gratificación orosensorial, así como los circuitos y áreas neuronales implicados más importantes. Se insiste en que el papel de la dieta no se restringe a su acción directa sobre el balance entre el ingreso y gasto energético, sino en la modulación que ejercen los componentes dietéticos sobre la regulación de la ingesta, expresión génica, termogénesis, lipogénesis/lipolisis, resistencia/sensibilidad a la insulina, características de la microbiota, etc. Se comentan algunos aspectos de la dieta en la prevención y tratamiento de la obesidad en el adulto y en el niño. Se revisan, tanto de forma cuantitativa como cualitativa, los diferentes tipos de tratamientos hipocalóricos y los objetivos prácticos para definir el ritmo de adelgazamiento y el peso final. Se concluye señalando la dificultad de mantener el peso perdido y la importancia de un planteamiento corrector personalizado basado en dietas adecuadas y precisas y de seguimiento a muy largo plazo
Aplicación de un test colorimétrico al estudio del rendimiento y vida útil en fritura de alimentos precocinados y frescos de aceite de oliva, aceite de girasol y su mezcla
The frying-life of olive oil, sunflower oil and a their homogeneous blend used in 40 repeated and discontinuous frying of different food, mostly precooked and frozen foods, were comparatively determined by using the qualitative color test “Fritest” and color developed at 500 nm using this test (A500). These measurements were significantly correlated (p< 0.001) to polar material, oligomer content and other thermaloxidation parameters The color selected to discard the oil -3 crosses- corresponds to A500 of 0.35 and to 25 % polar material and 10-15 % of oligomers. The shelf life (< 3 crosses or A500< 0.35) was 32 frying for olive oil, 22 fryings for sunflower oil, and 26 for their blend. The oil efficiency was assessed taking into account the weight decrease of foods, the oil loss, and the amount of food fried (kg food/L oil used) before oil discarding taking into account A500< 0,35 o A500< 0,4 cut-points. Olive oil presented a better efficiency (3.1 kg/L) than the sunflower oil and the blend (2.23 and 2.64 kg/L, respectively). Results suggest (i) the validity of the “Fritest” for a rapid evaluation of the alterations of different oils; (ii) the better efficiency and the longer shelf-life of olive oil than sunflower oil and the blend when frying different foods mostly pre-cooked and frozen foods.Se compara la vida útil de aceite de oliva, aceite de girasol y una mezcla de ambos utilizados en 40 frituras repetidas de alimentos, la mayoría precocinados y congelados, mediante el test cualitativo colorimétrico “Fritest” y la determinación del color desarrollado por dicho test a 500 nm. (A500) correlaciona muy significativamente (p< 0.001) con el material polar, contenido de oligómeros y otros parámetros de la alteración termoxidativa estudiados. El color para el cual debía eliminarse un aceite -3 cruces- se correspondió con una A500 de 0,35 y con 25% de material polar y con 12-15% de oligómeros. La vida útil de los aceites (< 3 cruces o A500< 0,35) fue de 32 frituras para el aceite de oliva, 22 para el de girasol y 26 para la mezcla. El rendimiento de los aceites se valoró en términos de merma ponderal de alimento, gasto de aceite y cantidad de alimento que pudo ser frito por litro de aceite antes de ser desechado atendiendo A500< 0,35 o A500< 0,4. El aceite de oliva presentó un rendimiento superior (3,1 kg de alimento/L de aceite) al de girasol y mezcla de aceites (2,23 y 2,64 kg/L, respectivamente). Estos resultados señalan (i) la validez del “Fritest” para la evaluación rápida de la vida útil de aceites de fritura y (ii) el mayor rendimiento y vida útil del aceite de oliva respecto al de girasol o la mezcla de aceites de oliva y girasol en fritura de alimentos la mayoría precocinados y congelados
Arilesterasa. Aspectos metodológicos y funcionales de una enzima clave en la enfermedad cardiovascular. Parte I
Cardiovascular diseases (CVD) are the first cause of death in developed countries and it is estimated that by 2010 they will also be the leading cause of death in developing countries. Epidemiologic studies have demonstrated that reduction of total serum cholesterol decreases prevalence and death rates associated with ischemic cardiopathy and CVD. Furthermore, a high concentration of LDL is considered a risk factor, while high levels of HDL are thought to be a protective factor. Many authors have suggested that HDL-bound PON1 enzyme may confer the protective effects to HDL. PON1 is an enzyme with several in vitro activities: paraoxonase, arylesterase, and lactonase. It has been reported that PON1 inhibits LDL and HDL peroxidation, as well as it facilitates the cholesterol reverse transport, helping to inhibit the development of atherosclerosis. Its native substrates, its in vivo mechanism of action and its molecular targets in the human body are still unknown. Nevertheless, calorimetric and spectrophotometric methods, very often employed but reaching to low very precise and sensible results, to determine its arylesterase activity have been developed. In this paper several aspects of this enzyme such as the mechanism of action, the regulation by substrates, genes and diet, are reviewed. Moreover, we present a method that uses a serum mimetic buffer that permits to obtain more precise and reproductible results of the arylesterase activity in humans and mice. Furthermore the relationship between PON1 polymorphisms and arylesterase activity is also tested in subjects at increased CVD-risk.Key Words: Arylesterase, atherosclerosis, oxidized-LDL, human serum mimetic, polymorphisms.Las enfermedades cardiovasculares (ECV) suponen la primera causa de muerte en los países desarrollados y se ha estimado que en el año 2010 también liderarán las causas de muerte en los países en vías de desarrollo. Numerosos estudios epidemiológicos han confirmado la relación entre colesterolemia y ECV, postulándose que el descenso de los niveles séricos de colesterol produce una disminución de la incidencia y la prevalencia de muerte por cardiopatía isquémica y ECV. Además se ha demostrado que la concentración elevada de lipoproteínas de baja densidad (LDL) es un factor de riesgo, mientras que la de lipoproteínas de alta densidad (HDL) es un factor protector frente a la ECV. Muchos autores han sugerido que esta acción beneficiosa de las HDL se debe a que unida a su molécula existe una enzima denominada paraoxonasa (PON1). La PON1 es un enzima que presenta varias actividades in vitro: paraoxonasa, arilesterasa, y lactonasa. Parece inhibir la oxidación tanto de las LDL como de las HDL y facilitar el transporte reverso del colesterol, disminuyendo así el riesgo de aterosclerosis. Su mecanismo de acción, propiedades catalíticas y sustratos naturales aun se desconocen. Se han desarrollado algunos métodos espectrofotométricos y calorimétricos para determinar su actividad arilesterasa que aunque muy utilizados no son muy sensibles y los resultados obtenidos no son muy reproducibles. En este trabajo se revisan muchos aspectos centrales referentes a esta enzima: mecanismos de acción, regulación por diferentes sustratos y mecanismos genéticos y dieta. Además se presenta un método que utilizando como tampón un mimético de suero permite obtener resultados más fiables y reproducibles de actividad arilesterasa en humanos y ratones. Por otra parte se detectan posibles efectos de los polimorfismos sobre los valores basales de actividad arilesterasa en individuos con riesgo cardiovascular incrementado.Palabras clave: arilesterasa, aterosclerosis, LDL-oxidada, mimético de suero humano, polimorfismos
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