Effects of a Calorie-Restricted Cafeteria Diet and Oleuropein Supplementation on Adiposity and mRNA Expression of Energy Balance Related Genes in Obese Male Rats

Supplementation with natural bioactive compounds has been proposed to be a complementary tool to the calorie-restricted diets and physical exercise programs used to tackle human overweight, obesity and Metabolic syndrome. Herein, we evaluated the effects of 14 weeks of calorie-restricted cafeteria diet either alone or combined with oral administration of the polyphenol oleuropein in obese adult male rats, compared with a control group fed standard chow and a group fed cafeteria diet. Animals were sacrificed at the age of 26 weeks and several tissues of interest were removed. The results showed that both dietary interventions reduced the adiposity index (p < 0.05 and p < 0.01, respectively), and specifically the abdominal fat depots (mesenteric: p < 0.01 and p < 0.01, respectively; and epididymal: both diets p < 0.001) and restored the decreased soleus skeletal muscle mass. Both interventions decreased leptin mRNA expression in mesenteric white adipose tissue (p < 0.05) and normalized hypothalamic Agrp mRNA expression compared to cafeteria-fed obese rats (p < 0.05). However, only the calorie-restricted cafeteria diet supplemented with oleuropein induced additional lower retroperitoneal adipose accretion (p < 0.05) and increased hypothalamic leptin receptor mRNA levels (p < 0.05). Experiments with female animals, at different doses and longer intervention periods, are needed to better determine the potential benefits of this dietary treatment

Behavioral and metabolic effects of a calorie-restricted cafeteria diet and oleuropein supplementation in obese male rats

Diet-induced obesity models are widely used to investigate dietary interventions for treating obesity. This study was aimed to test whether a dietary intervention based on a calorie-restricted cafeteria diet (CAF-R) and a polyphenolic compound (Oleuropein, OLE) supplementation modified sucrose intake, preference, and taste reactivity in cafeteria diet (CAF)-induced obese rats. CAF diet consists of high-energy, highly palatable human foods. Male rats fed standard chow (STD) or CAF diet were compared with obese rats fed CAF-R diet, alone or supplemented with an olive tree leaves extract (25 mg/kg*day) containing a 20.1% of OLE (CAF-RO). Biometric, food consumption, and serum parameters were measured. CAF diet increased body weight, food and energy consumption and obesity-associated metabolic parameters. CAF-R and CAF-RO diets significantly attenuated body weight gain and BMI, diminished food and energy intake and improved biochemical parameters such as triacylglycerides and insulin resistance which did not differ between CAF-RO and STD groups. The three cafeteria groups diminished sucrose intake and preference compared to STD group. CAF-RO also diminished the hedonic responses for the high sucrose concentrations compared with the other groups. These results indicate that CAF-R diet may be an efficient strategy to restore obesity-associated alterations, whilst OLE supplementation seems to have an additional beneficial effect on sweet taste function

The Role of Dietary Extra Virgin Olive Oil and Corn Oil on the Alteration of Epigenetic Patterns in the Rat DMBA-Induced Breast Cancer Model

Disruption of epigenetic patterns is a major change occurring in all types of cancers. Such alterations are characterized by global DNA hypomethylation, gene-promoter hypermethylation and aberrant histone modifications, and may be modified by environment. Nutritional factors, and especially dietary lipids, have a role in the etiology of breast cancer. Thus, we aimed to analyze the influence of different high fat diets on DNA methylation and histone modifications in the rat dimethylbenz(a)anthracene (DMBA)-induced breast cancer model. Female Sprague-Dawley rats were fed a low-fat, a high corn-oil or a high extra-virgin olive oil (EVOO) diet from weaning or from induction with DMBA. In mammary glands and tumors we analyzed global and gene specific (RASSF1A, TIMP3) DNA methylation by LUMA and bisulfite pyrosequencing assays, respectively. We also determined gene expression and enzymatic activity of DNA methyltransferases (DNMT1, DNMT3a and DNMT3b) and evaluated changes in histone modifications (H3K4me2, H3K27me3, H4K20me3 and H4K16ac) by western-blot. Our results showed variations along time in the global DNA methylation of the mammary gland displaying decreases at puberty and with aging. The olive oil-enriched diet, on the one hand, increased the levels of global DNA methylation in mammary gland and tumor, and on the other, changed histone modifications patterns. The corn oil-enriched diet increased DNA methyltransferase activity in both tissues, resulting in an increase in the promoter methylation of the tumor suppressor genes RASSF1A and TIMP3. These results suggest a differential effect of the high fat diets on epigenetic patterns with a relevant role in the neoplastic transformation, which could be one of the mechanisms of their differential promoter effect, clearly stimulating for the high corn-oil diet and with a weaker influence for the high EVOO diet, on breast cancer progression

Diets high in corn oil or extra-virgin olive oil differentially modify the gene expression profile of the mammary gland and influence experimental breast cancer susceptibility

Altres ajuts: This work was supported by Grants from "Fundación Patrimonio Comunal Olivarero" (FPCO2008-165.396; FPCO2013-CF611.084), "Organización Interprofesional del Aceite de Oliva Español" (OIP2009-165.646, "Departament de Salut i d'Agricultura, Alimentació i Acció Rural de la Generalitat de Catalunya" (GC2010-165.000)Nutritional factors, especially dietary lipids, may have a role in the etiology of breast cancer. We aimed to analyze the effects of high-fat diets on the susceptibility of the mammary gland to experimental malignant transformation. Female Sprague-Dawley rats were fed a low-fat, high-corn-oil, or high-extra-virgin olive oil (EVOO) diet from weaning or from induction. Animals were induced with 7,12-dimethylbenz[a]anthracene at 53 days and euthanized at 36, 51, 100 and 246 days. Gene expression profiles of mammary glands were determined by microarrays. Further molecular analyses were performed by real-time PCR, TUNEL and immunohistochemistry. Carcinogenesis parameters were determined at 105 and 246 days. High-corn-oil diet increased body weight and mass when administered from weaning. The EVOO diet did not modify these parameters and increased the hepatic expression of UCP2, suggesting a decrease in intake/expenditure balance. Both diets differentially modified the gene expression profile of the mammary gland, especially after short dietary intervention. Corn oil down-regulated the expression of genes related to immune system and apoptosis, whereas EVOO modified the expression of metabolism genes. Further analysis suggested an increase in proliferation and lower apoptosis in the mammary glands by effect of the high-corn-oil diet, which may be one of the mechanisms of its clear stimulating effect on carcinogenesis. The high-corn-oil diet strongly stimulates mammary tumorigenesis in association with modifications in the expression profile and an increased proliferation/apoptosis balance of the mammary gland. The online version of this article (doi:10.1007/s00394-015-0958-2) contains supplementary material, which is available to authorized users

Introducció a la Fisiologia Digestiva (I)

Continguts sobre fisiología digestiva corresponents a l'assignatura Fisiologia Mèdica I del Grau de Medicina de la Universitat Autònoma de Barcelon

Introducció a la Fisiologia Digestiva (I)

Continguts sobre fisiología digestiva corresponents a l'assignatura Fisiologia Mèdica I del Grau de Medicina de la Universitat Autònoma de Barcelon

L'alimentació durant el confinament

Aportacions divulgatives del personal docent i de recerca de la UAB en relació amb la pandèmia del coronaviru

Lípidos de la dieta y cáncer de mama

Els lípids de la dieta estimulen el càncer de mama en estudis experimentals. La major part dels estudis epidemiològics realitzats en humans també posen de manifest l'associació entre greixos i càncer de mama. El tipus i la quantitat de greix són factors importants que cal considerar, i la quantitat és el més fonamental. Quant al tipus, la majoria de greixos han mostrat propietats estimuladores del càncer de mama. L'acció s'efectua fonamentalment sobre la promoció de la carcinogènesi mamària. Únicament els poliinsaturats n-3 d'origen marí i l'àcid linoleic conjugat semblen ser inhibidors d'aquesta carcinogènesi. Els mecanismes implicats en l'acció estimuladora són de dos tipus: els que efectuen específicament els àcids grassos modificant estructures i/o funcions cel·lulars (membrana, transducció de senyals, síntesi d'eicosanoides, expressió gènica, etc.) i els que es poden donar de forma inespecífica en tots els tipus de càncers (aportació calòrica i contingut de substàncies alienes amb propietats carcinògenes o promotores)