|
|
||||||||
1 Institut National de la Recherche Agronomique et Centre de Recherche en Nutrition Humaine d'Auvergne, Unité d'Etude du Métabolisme Azoté, 63122 Ceyrat, France; and 2 Department of Cellular and Molecular Physiology, The Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033
We have investigated the effect of a postprandial
acute insulin deficiency induced by diazoxide injection on rat skeletal muscle protein synthesis. Diazoxide administration lowered plasma insulin >85% within 3 h after injection, whereas other hormones (insulin-like growth factor I, glucagon, corticosterone) involved in
the regulation of muscle protein synthesis were not altered significantly compared with control animals. The fractional rate of
muscle protein synthesis, measured in vivo, was reduced significantly (P < 0.05) in epitrochlearis (
46%),
gastrocnemius (
41%), and soleus (
35%). The reduction in
protein synthesis did not result from a reduced total RNA content but
was associated with diminished translation efficiency. Analysis of
ribosomal subunits revealed that the decreased translation efficiency
resulted from an impairment in the initiation phase of protein
synthesis. Diazoxide-induced insulin deficiency was associated with a
dramatic decrease in eukaryotic initiation factor (eIF) 4G bound to
eIF4E and a 2.5-fold increase in the amount of the
eIF4E · 4E-binding protein 1 (BP1) complex. In contrast, diazoxide injection did not change either the
relative amount of eIF4E present in gastrocnemius or its
phosphorylation state. These results indicate that an acute insulin
deficiency significantly decreases postprandial muscle protein
synthesis by modulating the interaction between 4E-BP1, eIF4G, and
eIF4E to control translation initiation.
postprandial insulin deficiency; eukaryotic initiation factors 4E and 4G; 4E-binding protein 1; translation initiation
This article has been cited by other articles:
![]() |
S. Fujita, B. B. Rasmussen, J. G. Cadenas, J. J. Grady, and E. Volpi Effect of insulin on human skeletal muscle protein synthesis is modulated by insulin-induced changes in muscle blood flow and amino acid availability Am J Physiol Endocrinol Metab, October 1, 2006; 291(4): E745 - E754. [Abstract] [Full Text] [PDF] |
||||
![]() |
I. Rieu, C. Sornet, G. Bayle, J. Prugnaud, C. Pouyet, M. Balage, I. Papet, J. Grizard, and D. Dardevet Leucine-Supplemented Meal Feeding for Ten Days Beneficially Affects Postprandial Muscle Protein Synthesis in Old Rats J. Nutr., April 1, 2003; 133(4): 1198 - 1205. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. R. Kimball, P. A. Farrell, and L. S. Jefferson Exercise Effects on Muscle Insulin Signaling and Action: Invited Review: Role of insulin in translational control of protein synthesis in skeletal muscle by amino acids or exercise J Appl Physiol, September 1, 2002; 93(3): 1168 - 1180. [Abstract] [Full Text] [PDF] |
||||
![]() |
M.-A. Arnal, L. Mosoni, D. Dardevet, M.-C. Ribeyre, G. Bayle, J. Prugnaud, and P. Patureau Mirand Pulse Protein Feeding Pattern Restores Stimulation of Muscle Protein Synthesis during the Feeding Period in Old Rats J. Nutr., May 1, 2002; 132(5): 1002 - 1008. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Dardevet, C. Sornet, G. Bayle, J. Prugnaud, C. Pouyet, and J. Grizard Postprandial Stimulation of Muscle Protein Synthesis in Old Rats Can Be Restored by a Leucine-Supplemented Meal J. Nutr., January 1, 2002; 132(1): 95 - 100. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Balage, S. Sinaud, M. Prod'Homme, D. Dardevet, T. C. Vary, S. R. Kimball, L. S. Jefferson, and J. Grizard Amino acids and insulin are both required to regulate assembly of the eIF4E {middle dot} eIF4G complex in rat skeletal muscle Am J Physiol Endocrinol Metab, September 1, 2001; 281(3): E565 - E574. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. Dardevet, C. Sornet, M. Balage, and J. Grizard Stimulation of In Vitro Rat Muscle Protein Synthesis by Leucine Decreases with Age J. Nutr., November 1, 2000; 130(11): 2630 - 2635. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. A. Farrell, J. M. Hernandez, M. J. Fedele, T. C. Vary, S. R. Kimball, and L. S. Jefferson Eukaryotic initiation factors and protein synthesis after resistance exercise in rats J Appl Physiol, March 1, 2000; 88(3): 1036 - 1042. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |