PMID- 20926761
OWN - NLM
STAT- MEDLINE
DCOM- 20110114
LR  - 20200930
IS  - 1522-1490 (Electronic)
IS  - 0363-6119 (Linking)
VI  - 299
IP  - 6
DP  - 2010 Dec
TI  - Dietary protein regulates hepatic constitutive protein anabolism in rats in a 
      dose-dependent manner and independently of energy nutrient composition.
PG  - R1720-30
LID - 10.1152/ajpregu.00497.2010 [doi]
AB  - We had previously observed that drastic increases in protein consumption greatly 
      modified hepatic protein anabolism in rats, but the confounding effects of other 
      macronutrient changes or a moderate protein increase to generate the same 
      modifications have not yet been established. This study examined the metabolic 
      and hormonal responses of rats subjected to 14-day isoenergetic diets containing 
      normal, intermediate, or high-protein levels (NP: 14% of energy, IP: 33%, HP: 
      50%) and different carbohydrate (CHO) to fat ratios within each protein level. 
      Fasted or fed rats (n = 104) were killed after the injection of a flooding dose 
      of (13)C-valine. The hepatic protein content increased in line with the dietary 
      protein level (P < 0.05). The hepatic fractional synthesis rates (FSR) of protein 
      were significantly influenced by both the protein level and the nutritional state 
      (fasted vs. fed) (P < 0.0001) but not by the CHO level, reaching on average 
      110%/day, 92%/day, and 83%/day in rats fed the NP, IP, and HP diets, 
      respectively. The FSR of plasma albumin and muscle did not differ between diets, 
      while feeding tended to increase muscle FSR. Proteolysis, especially the 
      proteasome-dependent system, was down-regulated in the fed state in the liver 
      when protein content increased. Insulin decreased with the CHO level in the diet. 
      Our results reveal that excess dietary protein lowers hepatic constitutive, but 
      not exported, protein synthesis rates, independently of the other macronutrients, 
      and related changes in insulin levels. This response was observed at the moderate 
      levels of protein intake (33%) that are plausible in a context of human 
      consumption.
FAU - Chevalier, Laure
AU  - Chevalier L
AD  - Institut National de la Recherche Agronomique, Centre de Recherche en 
      Nutrition-Humaine (CRNH-IdF), UMR 914, Nutrition Physiology and Ingestive 
      Behavior, Paris, France.
FAU - Bos, Cecile
AU  - Bos C
FAU - Azzout-Marniche, Dalila
AU  - Azzout-Marniche D
FAU - Dardevet, Dominique
AU  - Dardevet D
FAU - Tome, Daniel
AU  - Tome D
FAU - Gaudichon, Claire
AU  - Gaudichon C
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
DEP - 20101006
PL  - United States
TA  - Am J Physiol Regul Integr Comp Physiol
JT  - American journal of physiology. Regulatory, integrative and comparative 
      physiology
JID - 100901230
RN  - 0 (Dietary Proteins)
RN  - 0 (Proteins)
SB  - IM
MH  - Analysis of Variance
MH  - Animals
MH  - Body Weight
MH  - Dietary Proteins/*administration & dosage/metabolism
MH  - Dose-Response Relationship, Drug
MH  - Eating
MH  - Liver/drug effects/*metabolism
MH  - Male
MH  - Protein Biosynthesis/*drug effects
MH  - Proteins/*metabolism
MH  - Rats
MH  - Rats, Wistar
MH  - Reverse Transcriptase Polymerase Chain Reaction
EDAT- 2010/10/12 06:00
MHDA- 2011/01/15 06:00
CRDT- 2010/10/08 06:00
PHST- 2010/10/08 06:00 [entrez]
PHST- 2010/10/12 06:00 [pubmed]
PHST- 2011/01/15 06:00 [medline]
AID - ajpregu.00497.2010 [pii]
AID - 10.1152/ajpregu.00497.2010 [doi]
PST - ppublish
SO  - Am J Physiol Regul Integr Comp Physiol. 2010 Dec;299(6):R1720-30. doi: 
      10.1152/ajpregu.00497.2010. Epub 2010 Oct 6.