Associação entre colesterol hepático e ácido oleico no fígado de ratos tratados com gordura vegetal parcialmente hidrogenada

Objective The aim of the present study was to investigate the lipid profiles of the hepatic and adipose tissues of Wistar rats treated for 21 days with a diet high in saturated fat (high saturated fat, n=6) or high in hydrogenated fat, that is, having 50% partially hydrogenated vegetable oil in its composition (high hydrogenated fat, n=6), and compare them to those of a control group (control group, n=6). Methods Adipose tissue and total hepatic fat were higher in the saturated fat group than in the hydrogenated fat group. Hepatic lipid peroxidation was greatest in the saturated fat group, with consequent lower hepatic vitamin E and A levels. In contrast, serum vitamin A was highest in the saturated fat group. Analysis of hepatic lipid fractions found more cholesterol and less high density lipoprotein-cholesterol in the hydrogenated fat group. The hydrogenated fat group had the highest levels of triacylglycerols, followed by the saturated fat group. Results Significant amounts of trans fatty acids were detected in the hepatic and adipose tissues of the hydrogenated fat group. Among the identified fatty acids, 18:1n9 had a higher positive association with hepatic cholesterol and triacylglycerols, and a higher negative association with high density lipoprotein-cholesterol. Partially hydrogenated vegetable oil promotes greater accumulation of cholesterol and triacylglycerols in the liver than saturated fats. Conclusion Trans fatty acids were incorporated into hepatocytes and adipocytes in a highly efficient manner.OBJETIVO: Esta pesquisa investigou a composição lipídica dos tecidos hepático e adiposo de ratos Wistar tratados durante 21 dias com uma dieta rica em gordura saturada (grupo gordura saturada, n=6) ou rica em gordura hidrogenada, ou seja, 50% da gordura consistindo de gordura vegetal parcialmente hidrogenada (grupo gordura hidrogenada, n=6) e compará-los a um grupo-controle (grupo-controle, n=6). \ud MÉTODOS: As quantidades de tecido adiposo e gordura hepática total foram maiores no grupo gordura saturada do que no grupo gordura hidrogenada. A peroxidação lipídica hepática foi maior no grupo gordura saturada, com consequente diminuição dos níveis hepáticos de vitaminas E e A. Por outro lado, o nível sérico de vitamina A foi maior no grupo gordura saturada do que nos outros grupos. A análise das frações lipídicas hepáticas revelou mais colesterol e menos colesterol da lipoproteína de alta densidade no grupo gordura hidrogenada. O grupo gordura hidrogenada apresentou os maiores níveis de triglicérides, seguido do grupo gordura saturada. Quantidades significativas de ácidos graxos trans foram detectados nos tecidos hepático e adiposo do grupo gordura hidrogenada. \ud RESULTADOS: Dentre os ácidos graxos identificados, o 18:1n9 apresentou uma associação positiva maior com o colesterol hepático e triglicérides, e uma associação negativa maior com o colesterol da lipoproteína de alta densidade. A gordura vegetal parcialmente hidrogenada promove um maior acúmulo de colesterol e triglicérides no fígado do que a gordura saturada. \ud CONCLUSÃO: Os ácidos graxos trans foram incorporados aos hepatócitos e adipócitos de forma altamente eficiente.Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq), Brazi

DETERMINATION OF ENERGY VALUE OF HAMBURGERS AND MEATBALLS BY DIRECT CALORIMETRY AND FOOD ANALYSIS COMPOSITION. COMPARISON WITH NUTRITION INFORMATION DISPLAYED ON PACKAGES

The nutritional composition found in the laboratory and those present on labels of manufactured foods can differ significantly. The purpose of this study was to determine the nutritional composition of hamburgers and meatballs and compare them with your labels. The food analysis was performed following the Analytical Standards Institute`s Adolfo Lutz and energy content was determined by bomb calorimetry. Regarding the energy value, all the samples had values less than informed on the label. The content of lipids of hamburgers and meatballs ( except the beef) were lower than those reported on the label. The values of protein for the meatballs and chicken hamburger had lower values than those labels. Thus, the labels may overestimate as underestimate some nutritional values, leading to population erroneous information

High-Fat and Fat-Enriched Diets Impair the Benefits of Moderate Physical Training in the Aorta and the Heart in Rats

AIM: Millions of people die each year due to cardiovascular disease (CVD). A Western lifestyle not only fuses a significant intake of fat with physical inactivity and obesity but also promotes CVD. Recent evidence suggests that dietary fat intake impairs the benefits of physical training. We investigated whether aerobic training could reverse the adverse effects of a high-fat diet (HFD) on the aorta. Then, we explored whether this type of exercise could reverse the damage to the heart that is imposed by fat-enriched diet (FED). METHODS: Rats were randomly assigned to two experiments, which lasted 8 weeks each. First, rats swam for 60 min and were fed either a regular diet [standard diet (STD)] or an HFD. After aortic samples had been collected, the rats underwent a histopathological analysis for different biomarkers. Another experiment subjected rats that were fed either an STD or an FED to swimming for 20 or 90 min. RESULTS: The first experiment revealed that rats that were subjected to an HFD-endured increased oxidative damage in the aorta that exercises could not counteract. Together with increased cyclooxygenase 2 expression, an HFD in combination with physical training increased the number of macrophages. A reduction in collagen fibers with an increased number of positive α-actin cells and expression of matrix metalloproteinase-2 occurred concomitantly. Upon analyzing the second experiment, we found that physically training rats that were given an FED for 90 min/day decreased the cardiac adipose tissue density, although it did not protect the heart from fat-induced oxidative damage. Even though the physical training lowered cholesterol levels that were promoted by the FED, the levels were still higher than those in the animals that were given an STD. Feeding rats an FED impaired the swimming protocol’s effects on lowering triglyceride concentration. Additionally, exercise was unable to reverse the fat-induced deregulation in hepatic antioxidant and lipid peroxidation activities. CONCLUSION: Our findings reveal that an increased intake of fat undermines the potential benefits of physical exercise on the heart and the aorta