ABSTRACT
BACKGROUND: Non-alcoholic fatty liver disease (NAFLD) is increasingly recognized as a major cause of liver-related morbidity and mortality. The underlying mechanisms of disease progression remain poorly understood, and primary therapy of NAFLD is not yet established. We investigated the effects of dietary oleate on the development and progression of NAFLD in a methionine- and choline-deficient (MCD) diet-fed animal model. METHODS: A total of 30 C57BL/6J mice were randomly divided into three groups (n=10 in each group) and fed various experimental diets for four weeks: chow, MCD diet, or OMCD (MCD diet with oleate, 0.5 mg/g/day). Liver samples were examined for steatohepatitis and fibrosis parameters and associated genes. RESULTS: Additional dietary oleate dramatically reduced MCD diet-induced hepatic steatosis. Hepatic carbohydrate responsive element-binding protein was overexpressed in MCD diet-fed mice, and dietary oleate prevented this overexpression (P<0.001). Dietary oleate partially prevented MCD diet-induced serum level increases in aspartate aminotransferase and alanine aminotransferase (P<0.001, respectively). The mRNA expressions of hepatic monocyte chemoattractant protein 1, tumor necrosis factor-alpha and matrix metalloproteinase-9 were increased in MCD diet-fed mice, and this overexpression of inflammatory molecules was prevented by dietary oleate (P<0.001). Hepatic pericellular fibrosis was observed in MCD diet-fed mice, and dietary oleate prevented this fibrosis. Altogether, dietary oleate prevented MCD diet-induced hepatic steatosis, inflammation and fibrosis. CONCLUSION: Dietary oleate has beneficial effects in every step of NAFLD development and progression and could be a nutritional option for NAFLD prevention and treatment.
Subject(s)
Animals , Mice , Alanine Transaminase , Aspartate Aminotransferases , Chemokine CCL2 , Corneal Dystrophies, Hereditary , Diet , Disease Progression , Fatty Acids, Monounsaturated , Fatty Liver , Fibrosis , Inflammation , Liver , Matrix Metalloproteinase 9 , Models, Animal , Oleic Acid , RNA, Messenger , Tumor Necrosis Factor-alphaABSTRACT
OBJECTIVE: To analyze the monounsaturated and polyunsaturated trans fatty acid intake among the general population. METHODS: A cross-sectional study was conducted in São Paulo, Southeastern Brazil, in 2003, on a representative sample of 2,298 male and female subjects, including 803 adolescents (12 to 19 years), 713 adults (20 to 59 years) and 782 elderly people (60 years or over). Food intake was measured using 24-hour recall. Mean trans fatty acid intake was described according to gender and age group. RESULTS: The mean trans fatty acid intake was 5.0 g/day (SE = 0.1), accounting for 2.4 percent (SE = 0.1) of total energy and 6.8 percent (SE = 0.1) of total lipids. The adolescents had the highest mean intake levels (7.4 g/day; 2.9 percent of energy) while the adults and the elderly had similar intake (2.2 percent of energy for both; 6.4 percent of lipids and 6.5 percent of lipids, respectively). The mean trans fatty acid intake among adult and elderly women (approximately 2.5 percent of energy and 7.0 percent of lipids) was higher than among men in the same age group. The food item with the highest contribution towards trans fatty acids was margarine, accounting for more than 30 percent of total intake, followed by filled cookies among adolescents and meat among adults and the elderly. CONCLUSIONS: The trans fatty acid intake is above the level recommended by the World Health Organization. Replacement of the trans fatty acids in manufactured food items may be an effective measure for reducing trans fatty acid intake in Brazil.
OBJETIVO: Analisar o consumo de ácidos graxos monoinsaturados e poliinsaturados de configuração trans na população geral. MÉTODOS: Estudo transversal realizado em São Paulo, SP, 2003, com amostra representativa de 2.298 indivíduos, sendo 803 adolescentes (12 a 19 anos), 713 adultos (20 a 59 anos) e 782 idosos (60 anos ou mais), de ambos os sexos. O consumo alimentar foi medido por meio do recordatório alimentar de 24 horas. Os valores médios de ingestão de ácidos graxos trans foram descritos segundo sexo e faixa etária. RESULTADOS: O consumo médio de ácidos graxos trans foi de 5,0g/dia (EP=0,1), correspondendo a 2,4 por cento (EP=0,1) do total calórico e 6,8 por cento (EP=0,1) do total de lipídios. Os adolescentes apresentaram as maiores médias de ingestão (7,4g/dia e 2,9 por cento energia), enquanto os adultos e idosos registraram ingestão semelhante (2,2 por cento energia; 6,4 por cento lipídios e 6,5 por cento lipídios, respectivamente). As médias de consumo de ácidos graxos trans entre mulheres adultas e idosas (aproximadamente 2,5 por cento energia e 7,0 por cento lipídios) foram maiores que as médias dos homens de mesma faixa etária. O alimento de maior contribuição para o consumo de ácidos graxos trans foi a margarina, representando mais de 30 por cento do total ingerido, seguido do biscoito recheado para os adolescentes e da carne bovina para os adultos e idosos. CONCLUSÕES: O consumo de ácidos graxos trans encontra-se acima do preconizado pela Organização Mundial da Saúde. A substituição dos ácidos graxos trans dos alimentos industrializados pode ser uma medida eficaz para a redução do consumo desse tipo de gordura no Brasil.
Subject(s)
Humans , Male , Female , Child , Adolescent , Adult , Middle Aged , Young Adult , Energy Intake/physiology , Trans Fatty Acids/administration & dosage , Age Distribution , Brazil , Epidemiologic Methods , Margarine , Sex Distribution , Young AdultABSTRACT
OBJETIVO:Determinar se fontes lipídicas com diferentes razões de ácidos graxos insaturados e saturados (PUFA+MUFA)/SFA na dieta altera o perfil lipídico tecidual, a concentração de lipídios (mg/g) dos tecidos hepáticos e mesentérico e a digestibilidade lipídica. MÉTODOS: Foi realizada cromatografia gasosa para determinar o perfil de ácidos graxos nos tecidos hepático e adiposo de ratos alimentados com diferentes fontes lipídicas. O coeficiente de digestibilidade foi determinado a partir da relação entre a quantidade de lipídios consumidos e a quantidade fecal excretada. RESULTADOS:Diferentes fontes lipídicas (óleo de soja, manteiga, margarina e gorduras de porco e de peixe) não alteraram o coeficiente de digestibilidade e o peso hepático, mas alteraram a deposição de lipídios em todos os tecidos adiposos estudados. Não foi possível fazer a correlação direta entre o perfil dietário dos ácidos graxos não essenciais e sua deposição nos tecidos estudados, visto que a lipogênese de novo impede a identificação dos ácidos graxos dietários. CONCLUSÃO:Não foi constatada uma relação direta entre o perfil dietário dos ácidos graxos e sua deposição nos tecidos estudados, exceto para os ácidos graxos trans e linoléico (C18:2) que não são sintetizados no rato. Esses ácidos graxos apresentaram uma concentração tecidual diretamente proporcional àquela das fontes dietárias. Quanto à razão (PUFA+MUFA)/SFA, encontrada no tecido hepático dos diferentes grupos, observa-se que esta foi diretamente proporcional aos valores apresentados pelas fontes lipídicas dietárias. Entretanto, essa associação não foi observada nos tecidos adiposos analisados.
OBJECTIVE:To determine if lipid sources with different unsaturated to saturated fatty acid ratios, (PUFA+MUFA)/SFA in the diet alter the lipid profile of tissues, the lipid concentration (mg/g) of the hepatic and mesenteric tissues and the lipid digestibility. METHODS:Gas chromatography was used to determine the profile of fatty acids in the hepatic and adipose tissues of rats fed with different lipid sources. The digestibility coefficient was determined based on the ratio between lipid intake and excreted in the feces. RESULTS:Different lipid sources (soy oil, butter, margarine and pig and fish fat) did not alter the digestibility coefficient and the hepatic weight, but they altered the lipid deposition in all adipose tissue evaluated. No direct correlation was observed between dietary non-essential fatty acid profile and its deposition in the studied adipose tissues, because of de novo which impedes the identification of the dietary fatty acid. CONCLUSION:A direct relationship was not verified between the dietary fatty acid profile and its deposition in the studied adipose tissues, except for the trans and linoleic (C18:2) fatty acids which are not synthesized in the rat. The tissue concentration of these fatty acids was directly proportional to their dietary sources. The (PUFA+MUFA)/SFA ratio found in the hepatic tissue of the different groups, was directly proportional to the values presented in the dietary lipid sources. However, this association was not observed in the adipose tissue.