RESUMEN
Maternal nutritional programming by a high-fat (HF) diet is related to hepatic lipid accumulation and steatosis in offspring. Conjugated linoleic acid (CLA) might ameliorate impaired hepatic lipid homoeostasis; therefore, the aim was to investigate the potential preventive effect of maternal CLA consumption on TAG metabolism alterations induced by HF diets in adult male rat offspring receiving or not receiving CLA. Female Wistar rats were fed a control (C) diet, HF diet or HF diet supplemented with CLA (HF+CLA) for 4 weeks before mating and throughout pregnancy and lactation. After weaning, for 9 weeks, male offspring of C or HF rats continued with the same diets as their mothers (C/C or HF/HF groups, respectively) and male offspring of HF+CLA rats were fed HF or HF+CLA diets (HF+CLA/HF or HF+CLA/HF+CLA groups, respectively). Nutritional parameters, serum and liver TAG levels, the TAG secretion rate (TAG-SR) and the activities as well as gene expression of key hepatic enzymes involved in TAG regulation were assessed. The most interesting results were that maternal CLA decreased epididymal white adipose tissue weight and prevented serum and liver TAG accumulation induced by a HF diet in adult male offspring receiving or not receiving CLA. The prevention of liver steatosis in HF+CLA/HF+CLA and HF+CLA/HF offspring was associated with an increased hepatic TAG-SR. Overall, this study provides evidence that maternal CLA consumption programmes TAG regulation and in this way contributes to lowering lipid levels in tissues and preventing liver steatosis in particular.
Asunto(s)
Dieta Alta en Grasa/efectos adversos , Suplementos Dietéticos , Hígado Graso/prevención & control , Ácidos Linoleicos Conjugados/administración & dosificación , Efectos Tardíos de la Exposición Prenatal/prevención & control , Tejido Adiposo Blanco/metabolismo , Animales , Hígado Graso/etiología , Femenino , Hígado/metabolismo , Masculino , Exposición Materna/efectos adversos , Fenómenos Fisiologicos Nutricionales Maternos , Embarazo , Efectos Tardíos de la Exposición Prenatal/etiología , Ratas , Ratas WistarRESUMEN
Studies have reported the relationship between the excessive intake of saturated fatty acids (SFA) and trans fatty acids (t-FA) and an increased risk of cardiovascular disease. Since 2006, the MERCOSUR countries require that the mandatory nutrition labeling should include information not only about the content of SFA but also about the content of t-FA. This does not apply to fractionated products at the point of retail, such as bakery products. This paper aimed to determine the total fat content and the fatty acid profile in unpackaged traditional bakery products (breads, biscuits and pastries) in Santa Fe, Argentina. Except for French bread, the contribution of t-FA and SFA to the total FA consumption from baked products was high. On the other hand, due to the high variability detected in the FA composition of bakery products between bakeries, it would be necessary to implement regulations making nutrition labeling mandatory in these products.
Asunto(s)
Pan/análisis , Grasas de la Dieta/análisis , Ácidos Grasos/química , Análisis de los Alimentos , Etiquetado de Alimentos , ArgentinaRESUMEN
INTRODUCTION: The levels of docosahexaenoic acid (DHA, 22:6n-3) and arachidonic acid (AA, 20:4n-6) are critical for the normal structure and function of the brain. Trans fatty acids (TFA) and the source of the dietary fatty acids (FA) interfere with long-chain polyunsaturated fatty acids (LC-PUFA) biosynthesis. OBJECTIVES: The aim of this study was to investigate the effect of TFA supplementation in diets containing different proportions of n-9, n-6, and n-3 FA on the brain FA profile, including the retention of TFA, LC-PUFA levels, and n-6/n-3 PUFA ratios. These parameters were also investigated in the liver, considering that LC-PUFA are mainly bioconverted from their dietary precursors in this tissue and transported by serum to the brain. Also, stearoyl-CoA desaturase-1 (SCD1) and sterol regulatory element-binding protein-1c (SREBP-1c) gene expressions were evaluated. METHODS: Male CF1 mice were fed (16 weeks) diets containing different oils (olive, corn, and rapeseed) with distinct proportions of n-9, n-6, and n-3 FA (55.2/17.2/0.7, 32.0/51.3/0.9, and 61.1/18.4/8.6), respectively, substituted or not with 0.75% of TFA. FA composition of the brain, liver, and serum was assessed by gas chromatography. RESULTS: TFA were incorporated into, and therefore retained in the brain, liver, and serum. However, the magnitude of retention was dependent on the tissue and type of isomer. In the brain, total TFA retention was lower than 1% in all diets. DISCUSSION: Dietary n-3 PUFA decreased TFA retention and increased DHA accretion in the brain. The results underscore the importance of the type of dietary FA on the retention of TFA in the brain and also on the changes of the FA profile.
Asunto(s)
Encéfalo/efectos de los fármacos , Ácidos Docosahexaenoicos/administración & dosificación , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos trans/administración & dosificación , Animales , Ácido Araquidónico/administración & dosificación , Ácido Araquidónico/sangre , Encéfalo/metabolismo , Grasas de la Dieta/administración & dosificación , Ácidos Docosahexaenoicos/sangre , Ácidos Grasos Omega-3/sangre , Ácidos Grasos Omega-6/administración & dosificación , Ácidos Grasos Omega-6/sangre , Hígado/efectos de los fármacos , Hígado/metabolismo , Masculino , Ratones , Estearoil-CoA Desaturasa/genética , Estearoil-CoA Desaturasa/metabolismo , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/genética , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/metabolismo , Ácidos Grasos trans/sangreRESUMEN
The aim of this study was to investigate the effects of trans-fatty acids (TFA) on liver and serum TAG regulation in mice fed diets containing different proportions of n-3, n-6 and n-9 unsaturated fatty acids (UFA) from olive (O), maize (C) or rapeseed (R) oils partially substituted or not with TFA (Ot, Ct and Rt, respectively). Male CF1 mice were fed (30 d) one of these diets. The effects of the partial substitution (1 %, w/w) of different UFA with TFA on the activity and expression of hepatic enzymes involved in lipogenesis and fatty acids oxidation were evaluated, as well as their transcription factor expressions. Some of the mechanisms involved in the serum TAG regulation, hepatic VLDL rich in TAG (VLDL-TAG) secretion rate and lipoprotein lipase (LPL) activity were assessed. In liver, TFA induced an increase in TAG content in the Ot and Rt groups, and this effect was associated with an imbalance between lipogenesis and ß-oxidation. In the Ot group, exacerbated lipogenesis may be one of the mechanisms responsible for the liver steatosis induced by TFA, whereas in Rt it has been related to a decreased ß-oxidation, compared with their respective controls. The enhanced hepatic VLDL-TAG secretion in the Ot and Rt groups was compensated with a differential removal of TAG by LPL enzyme in extrahepatic tissues, leading to unchanged serum TAG levels. In brief, the effects of low levels of TFA on liver and serum TAG regulation in mice depend on the dietary proportions of n-3, n-6 and n-9 UFA.
Asunto(s)
Dieta Alta en Grasa/efectos adversos , Grasas Insaturadas en la Dieta/metabolismo , Aceites de Plantas/metabolismo , Ácidos Grasos trans/farmacología , Triglicéridos/metabolismo , Animales , Aceite de Maíz/química , Aceite de Maíz/metabolismo , Ácidos Grasos Omega-3/administración & dosificación , Ácidos Grasos Omega-3/metabolismo , Ácidos Grasos Omega-6/administración & dosificación , Ácidos Grasos Omega-6/metabolismo , Hígado Graso/metabolismo , Leucotrienos/metabolismo , Lipogénesis , Lipoproteína Lipasa/metabolismo , Lipoproteínas VLDL/metabolismo , Hígado/metabolismo , Masculino , Ratones , Aceite de Oliva/química , Aceite de Oliva/metabolismo , Oxidación-Reducción , Aceites de Plantas/química , Aceite de Brassica napus , Triglicéridos/biosíntesisRESUMEN
The process of regenerating liver is the result of a balance between stimulating factors and inhibitors of hepatocyte proliferation. Melatonin and its metabolites have been found to protect tissues against oxidative damage generated by a variety of toxic agents and metabolic processes. Furthermore, studies in liver of rats showed a decrease in the liver mitochondrial hydroxylation of drugs returning to the normal state after the administration of antioxidants. This study was designed to determine, in experimental animals, whether the administration of an antioxidant agent such as melatonin could prevent cells events leading to tissue injury and hepatic dysfunction after partial hepatectomy (PH). Biliary flow (BF), oxidative stress in hepatic tissue and Naâº/K⺠ATPase activities in whole plasma membrane were determined. PH decreased the Naâº/K⺠ATPase activity. PH significantly reduced the BF (36%) and promoted oxidative stress with an increase of lipoperoxidation and decrease of glutathione peroxidase and catalase activities. Treatment with melatonin prevented the decrease of BF in rats with hepatectomy and normalized the Naâº/K⺠ATPase activity. Moreover, melatonin markedly attenuated oxidative stress produced by PH. This may be the results of the higher efficacy of melatonin in scavenging various free radicals and also because of its ability in stimulating the antioxidant enzymes. We suggest that oxidative stress before and during liver regeneration has a crucial role in cholestasis, apoptotic/necrotic hepatocellular damage and the impairment in liver transport function induced by PH and that melatonin could modulate the degree of oxidative stress and through it prevent the alterations in liver function carrier.