title: Whole Rye Consumption Improves Blood and Liver n-3 Fatty Acid Profile and Gut Microbiota Composition in Rats.
abstract: BACKGROUND
  Whole rye (WR) consumption seems to be associated with beneficial health effects. Although rye fiber and polyphenols are thought to be bioactive, the mechanisms behind the health effects of WR have yet to be fully identified. This study in rats was designed to investigate whether WR can influence the metabolism of n-3 and n-6 long-chain fatty acids (LCFA) and gut microbiota composition.
  
  
  METHODS
  For 12 weeks, rats were fed a diet containing either 50% WR or 50% refined rye (RR). The WR diet provided more fiber (+21%) and polyphenols (+29%) than the RR diet. Fat intake was the same in both diets and particularly involved similar amounts of essential (18-carbon) n-3 and n-6 LCFAs.
  
  
  RESULTS
  The WR diet significantly increased the 24-hour urinary excretion of polyphenol metabolites-including enterolactone-compared with the RR diet. The WR rats had significantly more n-3 LCFA-in particular, eicosapentanoic (EPA) and docosahexanoic (DHA) acids-in their plasma and liver. Compared with the RR diet, the WR diet brought significant changes in gut microbiota composition, with increased diversity in the feces (Shannon and Simpson indices), decreased Firmicutes/Bacteroidetes ratio and decreased proportions of uncultured Clostridiales cluster IA and Clostridium cluster IV in the feces. In contrast, no difference was found between groups with regards to cecum microbiota. The WR rats had lower concentrations of total short-chain fatty acids (SCFA) in cecum and feces (p<0.05). Finally, acetate was lower (p<0.001) in the cecum of WR rats while butyrate was lower (p<0.05) in the feces of WR rats.
  
  
  CONCLUSIONS
  This study shows for the first time that WR consumption results in major biological modifications-increased plasma and liver n-3 EPA and DHA levels and improved gut microbiota profile, notably with increased diversity-known to provide health benefits. Unexpectedly, WR decreased SCFA levels in both cecum and feces. More studies are needed to understand the interactions between whole rye (fiber and polyphenols) and gut microbiota and also the mechanisms of action responsible for stimulating n-3 fatty acid metabolism.
authors: Laboratoire TIMC-IMAG CNRS UMR 5525, Equipe PRETA, Cœur et Nutrition, Université Joseph Fourier, Grenoble I, France.|Laboratory of Fundamental and Applied Bioenergetics (LBFA), Université Grenoble Alpes, Grenoble, France.|Inserm, U1055, Grenoble, France.
authors: Fayçal
authors: F
authors: Ounnas
authors: Laboratoire TIMC-IMAG CNRS UMR 5525, Equipe PRETA, Cœur et Nutrition, Université Joseph Fourier, Grenoble I, France.|Laboratory of Fundamental and Applied Bioenergetics (LBFA), Université Grenoble Alpes, Grenoble, France.|Inserm, U1055, Grenoble, France.
authors: Florence
authors: F
authors: Privé
authors: Laboratoire TIMC-IMAG CNRS UMR 5525, Equipe PRETA, Cœur et Nutrition, Université Joseph Fourier, Grenoble I, France.
authors: Patricia
authors: P
authors: Salen
authors: EA 4678 CIDAM, Clermont-Université, Université d'Auvergne, Clermont-Ferrand, France.
authors: Nadia
authors: N
authors: Gaci
authors: EA 4678 CIDAM, Clermont-Université, Université d'Auvergne, Clermont-Ferrand, France.
authors: William
authors: W
authors: Tottey
authors: LS9 Interlab Group, Laboratory of Phytochemicals in Physiology, Department of Food Science, University of Parma, Medical School, Building C, Via Volturno 39, 43125 Parma, Italy.
authors: Luca
authors: L
authors: Calani
authors: LS9 Interlab Group, Laboratory of Phytochemicals in Physiology, Department of Food Science, University of Parma, Medical School, Building C, Via Volturno 39, 43125 Parma, Italy.
authors: Letizia
authors: L
authors: Bresciani
authors: Department of Chemistry and Physics (Analytical Chemistry Area), Research Centre for Agricultural and Food Biotechnology (BITAL), Agrifood Campus of International Excellence, ceiA3, University of Almería, Carretera de Sacramento s/n, E-04120 Almería, Spain.
authors: Noelia
authors: N
authors: López-Gutiérrez
authors: Département de Biochimie, Pharmacologie et Toxicologie, Unité Biochimie Hormonale et Nutritionnelle, Centre Hospitalier et Universitaire de Grenoble, Grenoble, France.
authors: Florence
authors: F
authors: Hazane-Puch
authors: Département de Biochimie, Pharmacologie et Toxicologie, Unité Biochimie Hormonale et Nutritionnelle, Centre Hospitalier et Universitaire de Grenoble, Grenoble, France.
authors: François
authors: F
authors: Laporte
authors: EA 4678 CIDAM, Clermont-Université, Université d'Auvergne, Clermont-Ferrand, France.
authors: Jean-François
authors: JF
authors: Brugère
authors: LS9 Interlab Group, Laboratory of Phytochemicals in Physiology, Department of Food Science, University of Parma, Medical School, Building C, Via Volturno 39, 43125 Parma, Italy.
authors: Daniele
authors: D
authors: Del Rio
authors: Laboratory of Fundamental and Applied Bioenergetics (LBFA), Université Grenoble Alpes, Grenoble, France.|Inserm, U1055, Grenoble, France.
authors: Christine
authors: C
authors: Demeilliers
authors: Laboratoire TIMC-IMAG CNRS UMR 5525, Equipe PRETA, Cœur et Nutrition, Université Joseph Fourier, Grenoble I, France.
authors: Michel
authors: M
authors: de Lorgeril
mesh_terms: D000818:Animals; D001835:Body Weight; D002432:Cecum / Q000378:metabolism; D004032:Diet; D004281:Docosahexaenoic Acids / Q000097:blood / Q000378:metabolism; D015118:Eicosapentaenoic Acid / Q000097:blood / Q000378:metabolism; D015525:Fatty Acids, Omega-3 / Q000378:metabolism*; D043371:Fatty Acids, Omega-6 / Q000378:metabolism*; D005243:Feces; D005247:Feeding Behavior; D000069196:Gastrointestinal Microbiome; D007422:Intestines / Q000382:microbiology*; D008099:Liver / Q000378:metabolism*; D008297:Male; D013058:Mass Spectrometry; D020411:Oligonucleotide Array Sequence Analysis; D059808:Polyphenols / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D012434:Secale
chemical_list: D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D059808:Polyphenols; D004281:Docosahexaenoic Acids; D015118:Eicosapentaenoic Acid