title: Molecular alterations induced by a high-fat high-fiber diet in porcine adipose tissues: variations according to the anatomical fat location.
abstract: BACKGROUND
  Changing the energy and nutrient source for growing animals may be an effective way of limiting adipose tissue expansion, a response which may depend on the genetic background of the animals. This study aims to describe the transcriptional modulations present in the adipose tissues of two pig lines divergently selected for residual feed intake which were either fed a high-fat high-fiber (HF) diet or an isocaloric low-fat high-starch diet (LF).
  
  
  RESULTS
  Transcriptomic analysis using a porcine microarray was performed on 48 pigs (n = 12 per diet and per line) in both perirenal (PRAT) and subcutaneous (SCAT) adipose tissues. There was no interaction between diet and line on either adiposity or transcriptional profiles, so that the diet effect was inferred independently of the line. Irrespective of line, the relative weights of the two fat depots were lower in HF pigs than in LF pigs after 58 days on dietary treatment. In the two adipose tissues, the most apparent effect of the HF diet was the down-regulation of several genes associated with the ubiquitin-proteasome system, which therefore may be associated with dietary-induced modulations in genes acting in apoptotic and cell cycle regulatory pathways. Genes involved in glucose metabolic processes were also down-regulated by the HF diet, with no significant variation or decreased expression of important lipid-related genes such as the low-density lipoprotein receptor and leptin in the two fat pads. The master regulators of glucose and fatty acid homeostasis SREBF1 and MLXIPL, and peroxisome proliferator-activated receptor (PPAR)δ and its heterodimeric partner RXRA were down-regulated by the HF diet. PPARγ which has pleiotropic functions including lipid metabolism and adipocyte differentiation, was however up-regulated by this diet in PRAT and SCAT. Dietary-related modulations in the expression of genes associated with immunity and inflammation were mainly revealed in PRAT.
  
  
  CONCLUSIONS
  A high-fat high-fiber diet depressed glucose and lipid anabolic molecular pathways, thus counteracting adipose tissue expansion. Interaction effects between dietary intake of fiber and lipids on gene expression may modulate innate immunity and inflammation, a response which is of interest with regard to chronic inflammation and its adverse effects on health and performance.
authors.affiliation: INRA, UMR1348 Pegase, F-35590, Saint-Gilles, France. Florence.gondret@rennes.inra.fr.|Agrocampus-Ouest, UMR1348 Pegase, F-35000, Rennes, France. Florence.gondret@rennes.inra.fr.
authors.forename: Florence
authors.initials: F
authors.lastname: Gondret
authors.affiliation: INRA, UMR1348 Pegase, F-35590, Saint-Gilles, France. annie.vincent@rennes.inra.fr.|Agrocampus-Ouest, UMR1348 Pegase, F-35000, Rennes, France. annie.vincent@rennes.inra.fr.
authors.forename: Annie
authors.initials: A
authors.lastname: Vincent
authors.affiliation: Agrocampus-Ouest, UMR6625 IRMAR, F-35000, Rennes, France. magali.houee@agrocampus-ouest.fr.
authors.forename: Magalie
authors.initials: M
authors.lastname: Houée-Bigot
authors.affiliation: CNRS-Université de Rennes 1-INRIA, UMR6074 IRISA, Campus de Beaulieu, 35042, Rennes, Cedex, France. anne.siegel@irisa.fr.
authors.forename: Anne
authors.initials: A
authors.lastname: Siegel
authors.affiliation: INRA, UMR1348 Pegase, F-35590, Saint-Gilles, France. sandrine.lagarrigue@agrocampus-ouest.fr.|Agrocampus-Ouest, UMR1348 Pegase, F-35000, Rennes, France. sandrine.lagarrigue@agrocampus-ouest.fr.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Lagarrigue
authors.affiliation: INRA, UMR1348 Pegase, F-35590, Saint-Gilles, France. isabelle.louveau@rennes.inra.fr.|Agrocampus-Ouest, UMR1348 Pegase, F-35000, Rennes, France. isabelle.louveau@rennes.inra.fr.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Louveau
authors.affiliation: Agrocampus-Ouest, UMR6625 IRMAR, F-35000, Rennes, France. david.causeur@agrocampus-ouest.fr.
authors.forename: David
authors.initials: D
authors.lastname: Causeur
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D050154:Adiposity; D000818:Animals; D059305:Diet, High-Fat; D004041:Dietary Fats / Q000008:administration & dosage; D004043:Dietary Fiber / Q000008:administration & dosage*; D015536:Down-Regulation; D005786:Gene Expression Regulation; D053263:Gene Regulatory Networks; D050152:Intra-Abdominal Fat / Q000378:metabolism; D050356:Lipid Metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D050151:Subcutaneous Fat / Q000378:metabolism; D034421:Sus scrofa; D059467:Transcriptome
chemical_list: D004041:Dietary Fats; D004043:Dietary Fiber