RESUMEN
Interesterified fats have been used to replace trans-fat in ultra-processed foods. However, their metabolic effects are not completely understood. Hence, this study aimed to investigate the effects related to glucose homeostasis in response to interesterified palm oil or refined palm oil intake. Four-week-old male Swiss mice were randomly divided into four experimental groups and fed the following diets for 8 weeks: a normocaloric and normolipidic diet containing refined palm oil (PO group) or interesterified palm oil (IPO group); a hypercaloric and high-fat diet containing refined PO (POHF group) or interesterified PO (IPOHF group). Metabolic parameters related to body mass, adiposity and food consumption showed no significant differences. As for glucose homeostasis parameters, interesterified palm oil diets (IPO and IPOHF) resulted in higher glucose intolerance than unmodified palm oil diets (PO and POHF). Euglycemic-hyperinsulinemic clamp assessment showed a higher endogenous glucose production in the IPO group compared with the PO group. Moreover, the IPO group showed significantly lower p-AKT protein content (in the muscle and liver tissues) when compared with the PO group. Analysis of glucose-stimulated static insulin secretion (11.1 mmol/L glucose) in isolated pancreatic islets showed a higher insulin secretion in animals fed interesterified fat diets (IPO and IPOHF) than in those fed with palm oil (PO and POHF). Interesterified palm oil, including in normolipidic diets, can impair insulin signaling in peripheral tissues and increase insulin secretion by ß-cells, characterizing insulin resistance in mice.
Asunto(s)
Resistencia a la Insulina , Masculino , Animales , Ratones , Aceite de Palma , Aceites de Plantas , Grasas de la Dieta , Secreción de Insulina , Ácidos Grasos/análisis , Dieta Alta en Grasa/efectos adversos , GlucosaRESUMEN
The aim of this study was to investigate certain parameters regarding the maternal-fetal outcomes in a diet-induced obesity model. Obese, glucose-intolerant females who were exposed to a high-fat diet prior to pregnancy had lower placental efficiency and lower birth weight pups compared to the controls. Simple linear regression analyses showed that maternal obesity disrupts the proportionality between maternal and fetal outcomes during pregnancy. Maternal obesity is correlated with fetal outcomes, perhaps because of problems with hormonal signaling and exacerbation of inflammation in the maternal metabolic environment. The maternal obese phenotype altered the thickness of the placental layer, the transport of fatty acids, and the expression of growth factors. For example, lower expression of epidermal growth factor receptor (EGFR) mRNA in the obesity-prone group may have contributed to the rupture of the placental layers, leading to adverse fetal outcomes. Furthermore, maintenance of maternal glucose homeostasis and overexpression of placental growth factor (PGF) in the obesity-resistant group likely protected the placenta and fetuses from morphological and functional damage.
Asunto(s)
Dieta Alta en Grasa , Obesidad Materna , Animales , Dieta Alta en Grasa/efectos adversos , Femenino , Desarrollo Fetal , Retardo del Crecimiento Fetal/genética , Glucosa/metabolismo , Humanos , Ratones , Obesidad/metabolismo , Fenotipo , Placenta/metabolismo , Factor de Crecimiento Placentario/genética , Factor de Crecimiento Placentario/metabolismo , EmbarazoRESUMEN
High-fat diet (HFD) feeding is deleterious to hypothalamic tissue, leading to inflammation and lipotoxicity, as well as contributing to central insulin resistance. Autophagy is a process that restores cellular homeostasis by degrading malfunctioning organelles and proteins. Chronic HFD-feeding down-regulates hypothalamic autophagy. However, the effects of short-term HFD-feeding and the saturated fatty acid palmitate (PA) on hypothalamic autophagy and in neurones that express neuropeptide Y (NPY) and agouti-related peptide remains unknown. Therefore, we assessed hypothalamic autophagy after 1 and 3 days of HFD-feeding. We also injected PA i.c.v and analysed the modulation of autophagy in hypothalamic tissue. Both interventions resulted in changes in autophagy-related gene profiles without significant differences in protein content of p62 and LC3B-II, markers of the autophagy pathway. When we assessed native NPY neurones in brain slices from PA-treated animals, we observed increased levels of Atg7 and LC3B protein in response to PA treatment, indicating the induction of autophagy. We then tested the direct effects of fatty acids using the immortalised hypothalamic NPY-expressing neuronal cell model mHypoE-46. We found that PA, but not palmitoleate (PO) (a monounsaturated fatty acid), was able to induce autophagy. Co-treatment with PA and PO was able to block the PA-mediated induction of autophagy, as assessed by flow cytometry. When the de novo ceramide synthesis pathway was blocked with myriocin pre-treatment, we observed a decrease in PA-mediated induction of autophagy, although there was no change with the toll-like receptor 4 inhibitor, TAK-242. Taken together, these findings provide evidence that saturated and unsaturated fatty acids can differentially regulate hypothalamic autophagy and that ceramide synthesis may be an important mediator of those effects. Understanding the mechanisms by which dietary fats affect autophagy in neurones involved in the control of energy homeostasis will provide potential new pathways for targeting and containing the obesity epidemic.
Asunto(s)
Autofagia/efectos de los fármacos , Ácidos Grasos/farmacología , Neuronas/efectos de los fármacos , Animales , Autofagia/genética , Células Cultivadas , Dieta Alta en Grasa , Hipotálamo/efectos de los fármacos , Hipotálamo/metabolismo , Masculino , Ratones , Neuronas/metabolismo , Neuropéptido Y/metabolismo , Ácido Palmítico/farmacología , Factores de TiempoRESUMEN
BACKGROUND: Interesterified fats have largely replaced the partially hydrogenated oils which are the main dietary source of trans fat in industrialized food. This process promotes a random rearrangement of the native fatty acids and the results are different triacylglycerol (TAG) molecules without generating trans isomers. The role of interesterified fats in metabolism remains unclear. We evaluated metabolic parameters, glucose homeostasis and inflammatory markers in mice fed with normocaloric and normolipidic diets or hypercaloric and high-fat diet enriched with interesterified palm oil. METHODS: Male Swiss mice were randomly divided into four experimental groups and submitted to either normolipidic palm oil diet (PO), normolipidic interesterified palm oil diet (IPO), palm oil high-fat diet (POHF) or interesterified palm oil high-fat diet (IPOHF) during an 8â¯weeks period. RESULTS: When compared to the PO group, IPO group presented higher body mass, hyperglycemia, impaired glucose tolerance, evidence of insulin resistance and greater production of glucose in basal state during pyruvate in situ assay. We also observed higher protein content of hepatic PEPCK and increased cytokine mRNA expression in the IPO group when compared to PO. Interestingly, IPO group showed similar parameters to POHF and IPOHF groups. CONCLUSION: The results indicate that substitution of palm oil for interesterified palm oil even on normocaloric and normolipidic diet could negatively modulate metabolic parameters and glucose homeostasis as well as cytokine gene expression in the liver and white adipose tissue. This data support concerns about the effects of interesterified fats on health and could promote further discussions about the safety of the utilization of this unnatural fat by food industry.
Asunto(s)
Dieta Alta en Grasa , Ácidos Grasos/metabolismo , Homeostasis/efectos de los fármacos , Hígado/efectos de los fármacos , Aceite de Palma/administración & dosificación , Animales , Citocinas/metabolismo , Resistencia a la Insulina/fisiología , Hígado/metabolismo , RatonesRESUMEN
Diet is an important factor in both the pathogenesis and in the clinical course of Crohn's disease (CD). However, data on dietary patterns of CD patients are rather limited in the literature. This cross-sectional study included 60 patients with CD, aged 18-60 years. Dietary intake was assessed using a validated food frequency questionnaire to measure food consumption patterns by principal component analysis (PCA). Multiple regression analysis was performed to investigate the association between dietary patterns and clinical and demographic variables. Three dietary patterns were identified: "Traditional + FODMAP" was associated with symptoms, gender, previous surgeries, and duration of the disease. "Fitness style" was positively associated with physical activity and negatively associated with body mass index and smoking. "Snacks and processed foods" was positively associated with duration of the disease and negatively associated with age. According to the weekly food consumption analysis, patients with active disease consumed less coffee and tea. We found significant associations between the three dietary patterns and the variables, but not with the stage of the disease. Prospective studies are necessary to determine the effects of food consumption patterns on the clinical course of CD.
Asunto(s)
Enfermedad de Crohn/fisiopatología , Dieta , Adulto , Conducta Alimentaria , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Componente PrincipalRESUMEN
Interesterified fats have largely replaced hydrogenated vegetable fat, which is rich in trans fatty acids, in the food industry as an economically viable alternative, generating interest to study their health effects. The aim of this study was to evaluate the effect that interesterification of oils and fat has on lipid-induced metabolic dysfunction, hepatic inflammation and ER stress. Five week-old male Wistar rats were randomly divided into three experimental groups, submitted to either normocaloric and normolipidic diet containing 10% of lipids from unmodified soybean oil (SO) or from interesterified soybean oil (ISO), and one more group submitted to a high fat diet (HFD) containing 60% of fat from lard as a positive control, for 8 or 16 weeks. Metabolic parameters and hepatic gene expression were evaluated. The HFD consumption led to increased body mass, adiposity and impaired glucose tolerance compared to SO and ISO at both time points of diet. However, the ISO group showed an increased body mass gain, retroperitoneal WAT mass, fasting glucose, and impaired glucose tolerance during ipGTT at 16 weeks compared to SO. Moreover, at 8 weeks, hepatic gene expression of Atf3 and Tnf were increased in the ISO group compared to the SO group. Thus, replacement of natural fat with interesterified fat on a normocaloric and normolipidic diet negatively modulated metabolic parameters and resulted in impaired glucose tolerance in rats.