title: Excessive energy intake does not modify fed-state tissue protein synthesis rates in adult rats.
abstract: The impact of chronic excessive energy intake on protein metabolism is still controversial. Male Wistar rats were fed ad libitum during 5 weeks with either a high-fat high-sucrose diet (HF: n = 9) containing 45% of total energy as lipids (protein 14%; carbohydrate 40% with 83.5% sucrose) or a standard diet (controls: n = 10). Energy intake and body weight were recorded. At the end of the experiment, we measured body composition, metabolic parameters (plasma amino acid, lipid, insulin, and glucose levels), inflammatory parameter (plasma alpha2-macroglobulin), oxidative stress parameters (antioxidant enzyme activities, lipoperoxidation (LPO), protein carbonyl content in liver and muscle), and in vivo fed-state fractional protein synthesis rates (FSRs) in muscle and liver. Energy intake was significantly higher in HF compared with control rats (+28%). There were significant increases in body weight (+8%), body fat (+21%), renal (+41%), and epidydimal (+28%) fat pads in HF compared with control rats. No effect was observed in other tissue weights (liver, muscle, spleen, kidneys, intestine). Liver and muscle FSRs, plasma levels of lipids, glucose, insulin and alpha2-macroglobulin, soleus and liver glutathione reductase and peroxidase activities, MnSOD activity, LPO, and protein carbonyl content were not altered by the HF diet. Only soleus muscle and liver Cu/ZnSOD activity and soleus muscle catalase activities were reduced in HF rats compared with control rats. Thus, chronic excessive energy intake and increased adiposity, in the absence of other metabolic alterations, do not stimulate fed-state tissue protein synthesis rates.
authors.affiliation: INRA, UMR 1019 Nutrition Humaine, Saint Genès Champanelle, France.
authors.forename: Solange
authors.initials: S
authors.lastname: Adéchian
authors.forename: Silvana
authors.initials: S
authors.lastname: Giardina
authors.forename: Didier
authors.initials: D
authors.lastname: Rémond
authors.forename: Isabelle
authors.initials: I
authors.lastname: Papet
authors.forename: Daniela
authors.initials: D
authors.lastname: Buonocore
authors.forename: Claire
authors.initials: C
authors.lastname: Gaudichon
authors.forename: Dominique
authors.initials: D
authors.lastname: Dardevet
authors.forename: Fulvio
authors.initials: F
authors.lastname: Marzatico
authors.forename: Laurent
authors.initials: L
authors.lastname: Mosoni
mesh_terms: D000596:Amino Acids / Q000097:blood; D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D001823:Body Composition / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D019422:Dietary Sucrose / Q000494:pharmacology*; D004435:Eating / Q000502:physiology*; D002149:Energy Intake / Q000502:physiology*; D007249:Inflammation / Q000503:physiopathology; D007333:Insulin Resistance / Q000502:physiology; D008055:Lipids / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D023421:Models, Animal; D018482:Muscle, Skeletal / Q000187:drug effects / Q000378:metabolism*; D018384:Oxidative Stress / Q000502:physiology; D011506:Proteins / Q000187:drug effects* / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000596:Amino Acids; D001786:Blood Glucose; D019422:Dietary Sucrose; D008055:Lipids; D011506:Proteins