title: Long-term intake of a high prebiotic fiber diet but not high protein reduces metabolic risk after a high fat challenge and uniquely alters gut microbiota and hepatic gene expression.
abstract: A mismatch between early developmental diet and adulthood may increase obesity risk. Our objective was to determine the effects of re-matching rats to their weaning diets high in protein or fiber after transient high-fat/high-sucrose challenge in adulthood. We hypothesize that a long-term high fiber diet will be associated with a gut microbiota and hepatic gene expression reflective of reduced adiposity. Wistar rat pups were fed a control (C), high prebiotic fiber (HF), or high protein (HP) diet from 3-15 weeks of age; a high-fat/high-sucrose diet from 15-21 weeks; their respective C, HF, or HP diets from 21-25 weeks. Gut microbiota of cecal contents and hepatic gene expression were measured when rats were terminated at 25 weeks of age. HF rats had higher total bacteria, bifidobacteria and Bacteroides/Prevotella spp than C and HP at 25 weeks (P < 0.05). Firmicutes, especially Clostridium leptum, decreased in HF compared to C and HP (P < .05). The ratio of Firmicutes:Bacteroidetes was markedly lower in HF versus C and HP at 25 weeks (P < .05). HF decreased hepatic cholesterol content compared to HP and C at 25 weeks. HF and HP increased 3-hydroxy-3-methylglutaryl-CoA reductase mRNA and decreased lecithin-cholesterol acyltransferase mRNA compared to C (P < .05). In conclusion, re-matching rats to a HF but not HP diet attenuated the typical increase in Firmicutes:Bacteroidetes ratio associated with consumption of a high fat diet. Lower hepatic cholesterol with long-term HF diet intake may be related to alterations in gut microbiota and hepatic lipid metabolism.
authors.affiliation: Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada T2N 1N4. Electronic address: dcsaha@ucalgary.ca.
authors.forename: Dolan C
authors.initials: DC
authors.lastname: Saha
authors.affiliation: Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada T2N 1N4; Department of Biochemistry and Molecular Biology, University of Calgary, Calgary, AB, Canada T2N 4N1. Electronic address: reimer@ucalgary.ca.
authors.forename: Raylene A
authors.initials: RA
authors.lastname: Reimer
mesh_terms: D050154:Adiposity; D000818:Animals; D001419:Bacteria / Q000187:drug effects / Q000254:growth & development; D002432:Cecum / Q000382:microbiology*; D002784:Cholesterol / Q000378:metabolism*; D004032:Diet / Q000009:adverse effects; D059305:Diet, High-Fat; D004041:Dietary Fats / Q000009:adverse effects* / Q000378:metabolism; D004043:Dietary Fiber / Q000494:pharmacology / Q000627:therapeutic use*; D004044:Dietary Proteins / Q000008:administration & dosage / Q000494:pharmacology*; D005247:Feeding Behavior; D005260:Female; D015870:Gene Expression / Q000187:drug effects; D006903:Hydroxymethylglutaryl CoA Reductases / Q000235:genetics / Q000378:metabolism; D050356:Lipid Metabolism / Q000187:drug effects / Q000235:genetics; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D064307:Microbiota / Q000187:drug effects; D009765:Obesity / Q000378:metabolism / Q000517:prevention & control*; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000235:genetics / Q000378:metabolism; D056692:Prebiotics; D012333:RNA, Messenger / Q000378:metabolism; D017208:Rats, Wistar; D014886:Weaning
chemical_list: D004041:Dietary Fats; D004043:Dietary Fiber; D004044:Dietary Proteins; D056692:Prebiotics; D012333:RNA, Messenger; D002784:Cholesterol; D006903:Hydroxymethylglutaryl CoA Reductases; D007862:Phosphatidylcholine-Sterol O-Acyltransferase
keywords: Cholesterol; Gut microbiota; Lipid metabolism; Obesity; Prebiotic fiber; Rat