Modificaciones de las lipoproteínas del plasma en voluntarios sometidos a dietas preparadas con aceite de girasol solo o mezclado con oleína de palma / Changes in the content of plasma lipoproteins in persons subjected to diets prepared with sunflower oil alone or mixed with palm olein

En 31 comensales regulares del Comedor Universitario de la Universidad Central de Venezuela (CUUCV), en Caracas. Se observó el efecto de la sustitución del aceite de girasol que se utiliza corrientemente en la preparación de las comidas en ese comedor, por un aceite obtenido de la mezcla de aceite de girasol y oleína de palma, en la proporción 70/30 (v/v) respectivamente. Después de 40 días continuos de la sustitución no hubo cambios significativos en las concentraciones de colesterol total (CT), ni del colesterol de las lipoproteínas de baja densidad (LDL) y muy baja densidad (VLDL). La concentración del colesterol de las lipoproteínas de alta densidad (HDL) aumentó significativamente (p<0,05). Los triglicéridos (TG) del plasma aumentaron en un 30%. La resistencia a la oxidación de las LDL aumentó considerablemente (p< 0,01). Hoy se considera a esta resistencia como un factor protector de gran importancia en la prevención del inicio del proceso aterogénico. Tomando en cuenta las modificaciones favorables como el aumento de colesterol de HDL sin modificación de la LDL y el claro aumento de la resistencia a la oxidación de la LDL, se considera que la oleína de palma es un aceite vegetal que puede ser utilizado sin mayores riesgos en mezcla con otros aceites que tengan una relación linoleico/palmítico más elevada como los aceites de girasol, maíz, soja y otros.

We analyzed in 31 subjects, regular guests of the University food service of the Central University of Venezuela (UCVFS), in Caracas, the effects of replacing sunflower oil, commonly used in the preparation of meals, by a mix of sunflower oil and palm olein 70/30 (v/v) respectively. Plasma concentrations of total cholesterol, low and very low density lipoproteins were not changed after 40 days of the substitution. On the contrary, concentrations of high density lipoprotein and total triglycerides increased. The resistance to the oxidation of low-density lipoproteins increased considerably (p<0, 01). Today this resistance is considered as a protective factor of great importance in the prevention of the initiation of the atherogenic process. Taking into account the favorable modifications of HDL cholesterol and the clear increased resistance to the oxidation of LDL, we think that palm olein, mixed with other oils with a high ratio linoleic/palmític (sunflower, corn, soya an the likes), can be used as a healthy alternative in human nutrition.

Paradoxical effect of a pequi oil-rich diet on the development of atherosclerosis: balance between antioxidant and hyperlipidemic properties

Pequi is the fruit of Caryocar brasiliense and its oil has a high concentration of monounsaturated and saturated fatty acids, which are anti- and pro-atherogenic agents, respectively, and of carotenoids, which give it antioxidant properties. Our objective was to study the effect of the intake of a cholesterol-rich diet supplemented with pequi oil, compared to the same diet containing soybean oil, on atherosclerosis development, and oxidative stress in atherosclerosis-susceptible LDL receptor-deficient mice (LDLr-/-, C57BL/6-background). Female mice were fed a cholesterol-rich diet containing 7% soybean oil (Soybean group, N = 12) or 7% pequi oil (Pequi group, N = 12) for 6 weeks. The Pequi group presented a more atherogenic lipid profile and more advanced atherosclerotic lesions in the aortic root compared to the Soybean group. However, the Pequi group presented a less advanced lesion in the aorta than the Soybean group and showed lower lipid peroxidation (Soybean group: 50.2 ± 7.1; Pequi group: 30.0 ± 4.8 µmol MDA/mg protein) and anti-oxidized LDL autoantibodies (Soybean group: 35.7 ± 9.4; Pequi group: 15.6 ± 3.7 arbitrary units). Peritoneal macrophages from the Pequi group stimulated with zymosan showed a reduction in the release of reactive oxygen species compared to the Soybean group. Our data suggest that a pequi oil-rich diet slows atherogenesis in the initial stages, possibly due to its antioxidant activity. However, the increase of serum cholesterol induces a more prominent LDL migration toward the intimae of arteries, increasing the advanced atherosclerotic plaque. In conclusion, pequi oil associated with an atherogenic diet worsens the lipid profile and accelerates the formation of advanced atherosclerotic lesions despite its antioxidant action.

Progress on relationship between omega-3 polyunsaturated fatty acids and violent-aggressive behavior / 法医学杂志

The relationship between omega-3 polyunsaturated fatty acids (PUFAs) and violent-aggressive behavior has been payed attention since 1980s. Their correlation was explored by many epidemiological investigations, and the effect of PUFAs on prevention or reduction of violent-aggressive behavior in different groups were also affirmed by some intervention studies. This article summarized the previous studies and reviewed the history of epidemiological or intervention studies on PUFAs and its relationship with violent-aggressive behavior. It also presented the possible influencing factors in these studies and possible mechanisms.

Fresh soy oil protects against vascular changes in an estrogen-deficient rat model: an electron microscopy study

OBJECTIVE: To observe the effects of consuming repeatedly heated soy oil on the aortic tissues of estrogen-deficient rats. METHODS: Thirty female Sprague Dawley rats (200- 250 g) were divided equally into five groups. One group served as the normal control (NC) group. The four treated groups were ovariectomized and were fed as follows: 2 percent cholesterol diet (OVXC); 2 percent cholesterol diet + fresh soy oil (FSO); 2 percent cholesterol diet + once-heated soy oil (1HSO); and 2 percent cholesterol diet + five-times-heated soy oil (5HSO). After four months, the rats were sacrificed, and the aortic tissues were obtained for histological studies. RESULTS: After four months of feeding, the NC, FSO and 1HSO groups had a lower body weight gain compared to the OVXC and 5HSO groups. The tunica intima/media ratio in the 5HSO group was significantly thicker (p < 0.05) compared to the NC, OVXC and FSO groups. Electron microscopy showed that endothelial cells were normally shaped in the FSO and NC groups but irregular in the 1HSO and 5HSO groups. A greater number of collagen fibers and vacuoles were observed in the 5HSO group compared to the other treatment groups. CONCLUSIONS: Fresh soy oil offered protection in the estrogen-deficient state, as these rats had similar features to those of the NC group. The damage to the tunica intima and the increase in the ratio of tunica intima/media thickness showed the deleterious effect of consuming repeatedly heated soy oil in castrated female rats.

Aceites de origen marino; su importancia en la nutrición y en la ciencia de alimentos / Marine oils; nutritional and food science relevance

Marine oils are today valuable products with widely nutritional and food applications because of their high content of long-chain omega-3 fatty acids. Originally, marine oils were by-products from the manufacture of fish meal. However, research in the last years has demonstrated important health benefits of long-chain omega-3 fatty acids for both humans and animals. The present work reviews the health and nutritional effects of the most important omega-3 marine oils fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid fDHAJ), the nutritional bioavailabitity of these fatty acids, the technological alternatives to include them into different foods, and the actual great valorization of DHA. Also, it discusses the incorporation of these fatty acids to public nutritional and health policies, and the technological challenge that must be encouraged by the fish oil producers to incorporate into their manufacture practices to the requirements of the new nutritional utilization of these valuable products.

Los aceites de origen marino son hoy en día valiosos productos con gran aplicación nutricional y alimentaria por su alto contenido de ácidos grasos omega-3 de cadena larga. Originalmente estos aceites eran solo un sub-producto de la fabricación de harina de pescado. Sin embargo, la investigación en los últimos años ha demostrado sus importantes beneficios en la salud tanto humana como animal. El presente trabajo analiza los efectos en la salud y en la nutrición de los principales ácidos grasos omega-3 de origen marino (eicosapentaenoico, EPA y docosahexaenoico, DHA), la biodisponibilidad nutritional de estos ácidos grasos, las alternativas tecnológicas para incorporarlos a diferentes alimentos, la gran valorización actual del DHA, la incorporación de los ácidos grasos omega-3 a las políticas públicas de salud y nutrición, y el desafío tecnológico que significa para las actuales empresas productoras de aceite de pescado el incorporarse a esta nueva modalidad de utilización nutricional de este valioso producto.

Influências de dietas ricas em ácidos graxos saturados e insaturados sobre o miocárdio de ratos / Influences of rich in saturated and unsaturated fatty acids diets in rat myocardium

OBJETIVOS: O estudo avaliou a influência de dietas ricas em ácidos graxos saturados (AGS) e ácidos graxos insaturados (AGI) sobre a função mecânica, a morfologia e o estresse oxidativo do miocárdio de ratos. MÉTODOS: Ratos Wistar com 60 dias de idade foram alimentados com dieta padrão (n = 8) ou dietas ricas em AGS (n = 8) ou AGI (n = 8) durante 60 dias. A função mecânica foi avaliada em músculo papilar isolado do ventrículo esquerdo (VE) por meio de contrações isométrica e isotônica, em condição basal (1,25 mM de cálcio), após elevação da concentração extracelular de cálcio para 5,2 mM e estimulação beta-adrenérgica com isoproterenol 1,0 µM. Fragmentos do VE foram usados para estudo de estresse oxidativo e microscopias óptica e eletrônica. RESULTADOS: As dietas suplementadas com AGS e AGI não alteraram a função mecânica do músculo cardíaco. Entretanto, ambas provocaram estresse oxidativo, com aumento do hidroperóxido de lipídio e redução da concentração de superóxido dismutase. A dieta AGI diminuiu a expressão da catalase e a AGS reduziu a quantidade de glutationa peroxidase miocárdica. Ambas as dietas promoveram discretas alterações morfológicas visualizadas ultra-estruturalmente, como depósitos lipídicos e lesões das membranas celulares. CONCLUSÃO: Os resultados sugerem que dietas enriquecidas com AGS e AGI não acarretam alteração da função mecânica do músculo cardíaco isolado, mas causam discretas lesões estruturais e estresse oxidativo no miocárdio.

OBJECTIVES: To study the influence of saturated (SFA) and unsaturated fatty acid (UFA) rich diets on mechanical function, morphology and oxidative stress in rat myocardium. METHODS: Male, 60-day-old Wistar rats were fed a control (n=8), a SFA (n=8), or a UFA-rich diet (n=8) for sixty days. Mechanical function was studied in isolated left ventricle papillary muscle under isometric and isotonic contractions, in basal conditions (1.25mM calcium chloride) and after 5.2mM calcium chloride and beta-adrenergic stimuli with 1.0µM isoproterenol. Left ventricle fragments were used to study oxidative stress and morphology under light and electron microscopy. RESULTS: SFA and UFA-rich diets did not change myocardium mechanical function. Both diets caused oxidative stress, with high lipid hydroperoxide and low superoxide-dismutase concentrations. UFA rich diet decreased catalase expression and SFA rich diet decreased the amount of myocardial glutathione-peroxidase. Both diets promoted light ultrastructural injuries such as lipid deposits and cell membrane injuries. CONCLUSION: Results suggest that SFA and UFA rich diets do not alter isolated muscle mechanical function, but promote light myocardial morphological injuries and oxidative stress.

Effect of unsaturated fatty acids on myocardial performance, metabolism and morphology

Diets rich in saturated fatty acids are one of the most important causes of atherosclerosis in men, and have been replaced with diets rich in unsaturated fatty acids (UFA) for the prevention of this disorder. However, the effect of UFA on myocardial performance, metabolism and morphology has not been completely characterized. The objective of the present investigation was to evaluate the effects of a UFA-rich diet on cardiac muscle function, oxidative stress, and morphology. Sixty-day-old male Wistar rats were fed a control (N = 8) or a UFA-rich diet (N = 8) for 60 days. Myocardial performance was studied in isolated papillary muscle by isometric and isotonic contractions under basal conditions after calcium chloride (5.2 mM) and ß-adrenergic stimulation with 1.0 æM isoproterenol. Fragments of the left ventricle free wall were used to study oxidative stress and were analyzed by light microscopy, and the myocardial ultrastructure was examined in left ventricle papillary muscle. After 60 days the UFA-rich diet did not change myocardial function. However, it caused high lipid hydroperoxide (176 ± 5 vs 158 ± 5, P < 0.0005) and low catalase (7 ± 1 vs 9 ± 1, P < 0.005) and superoxide-dismutase (18 ± 2 vs 27 ± 5, P < 0.005) levels, and discrete morphological changes in UFA-rich diet hearts such as lipid deposits and mitochondrial membrane alterations compared to control rats. These data show that a UFA-rich diet caused myocardial oxidative stress and mild structural alterations, but did not change mechanical function.

Olive: fruit of peace against cancer.

The olive has a history almost as long as that of Western civilization and has been looked upon as a sign of hope, peace, and sacredness. Olive oil, extracted from the olive, is the principal source of dietary fat in the Mediterranean basin. The composition differs from that of other dietary fats in that olive oil is rich in monounsaturated fatty acids. Even other than as a source of monounsaturated fats, olive oil has own unique effects. Accumulating evidence suggests that olive oil may have beneficial health effects, especially when it comes to reducing risk factors for coronary heart diseases, preventing cancer, and modifying immune and inflammatory responses. However, evidence remains limited, definitive conclusions are difficult to draw, and there remains a significant need for further studies, particularly prospective cohort and well-designed, controlled intervention studies. In this manuscript, the beneficial health effects of olive oil are reviewed, with particular attention paid to cancer prevention and immune functions..

Blocking of alcohol-induced effects on synthesis and secretion of apo B containing lipoproteins by substituting sardine oil in the diet.

The effect of substitution of fish oil in the diet on the alcohol-induced changes in the metabolism of very low density lipoprotein (VLDL) by primary cultures of rat hepatocytes has been studied. Rats fed groundnut oil diet or sardine oil diet were given alcohol (3 g/kg) for 4 weeks. Substitution of fish oil for groundnut oil in the diet blocked the hypertriglyceridemia and hyperlipoproteinemia caused by alcohol. Enhanced incorporation of [3H]leucine into apo B secreted into the medium and [14C]acetate into lipids associated with secreted VLDL indicated an increased rate of synthesis of apo B containing lipoproteins by hepatocytes from livers of rats receiving alcohol. Fish oil in the diet reduced incorporation of [3H]leucine into apo B and that of [14C]acetate into lipids indicating a lower rate of synthesis of apo B containing lipoproteins. Pulse chase experiments confirmed the above observation. Thus it is suggested that fish oil in the diet prevents hyperlipoproteinemia caused by alcohol possibly by reducing the synthesis and secretion of VLDL by liver.

Respuesta de los ácidos grasos omega 3 y omega 6 del cerebro y eritrocitos de la progenie a la suplementación de la dieta de la nodriza con dos concentraciones de aceite de pescado / Response of omega 3 and omega 6 fatty oils of pups brains and erythrocytes to mother diet supplementation with 2 fish oil concentrations

Se evaluó el efecto de suplementar la dieta de la nodriza, con dos concentraciones de aceite de pescado, en el contenido de los ácidos grasos omega 3 y omega 6 altamente polisaturados (ò20C), de los lípidos de la leche y de los fosfolípidos del cerebro y glóbulos rojos de la progenie. Ratas preñadas cepa Wistar, se dividieron en tres grupos. Cada grupo fue alimentado, desde un día antes y durante 18 días post parto, con una de tres dietas. La dieta control contenía aceite de soya 10g/100g dieta, las dietas experimentales se prepararon reemplazando 0,2 o 0,6 gramos de aceite vegetal por aceite de pescado. El contenido de los ácidos grasos omega 3 (20:5n-3; EPA y 22:6n-3; DHA) y omega 6 (20:4n-6; AA), en la leche a los 18 días post parto, estuvo determinado por la magnitud de la suplementación. El más alto contenido de DHA y EPA y el menor contenido de AA, en glóbulos rojos, se observó en las crías de madres que consumieron la dieta con 0,2 por ciento de aceite de pescado. La concentración máxima de DHA y AA en el cerebro de la progenie, se logró con la leche de las nodrizas que consumieron la dieta 0,6 por ciento de aceite de pescado, la que aumentó la concentración del DHA y del AA en la leche a 1,44 por ciento y 1,15 por ciento de los ácidos grasos totales, respectivamente

Efecto del aumento de los ácidos grasos poliinsaturados (Omega 6) dietéticos en el contenido de glutatión hepático y actividad de gama glutamil transpeptidasa en riñón de ratas / Effect of increase of dietary polyunsaturated fatty acids (Omega 6) on the hepatic glutathione content and gamma-glutamil transpeptidase activity in kidney of rats

Se estudió el efecto de la alimentación de ratas macho, cepa Wistar, desde los 24 a los 52 días de edad, con dietas de frijol deficientes en aminoácidos azufrados o suplementados con 0.3% DL-metionina y con dos concentraciones de aceite de maíz, 2% y 20% (g/Kg dieta), sobre el contenido de glutatión en hígado (GSH) y sobre la actividad de gama glutamil transpeptidasa renal (GGTP) (E.C.2.3.2.2.). Los resultados indicaron que las ratas alimentadas con la dieta de frijol con 2% de aceite de maíz, disminuyeron significativamente el contenido de GSH hepático y la actividad de GGTP renal. La suplementación con 0.3% de metionina y/o el incremento al 20% del aceite de maíz en la dieta, estimularon significativamente el contenido de GSH hepático y la actividad transpeptidásica en el riñon. Se postula que el aumento de los ácidos grasos poliinsaturados estimuló la actividad de GGTP vcomo una manera de aumentar la biodisponibilidad de sustratos para síntese de novo de GSH hepático, necesário para la protecciójn de la formación de hidroperóxidos atribuido al incremento de los ácidos grasos poliinsaturados a nivel celular