|Davis, Teresa -|
|Suryawan, Agus -|
|Orellana, Renan -|
|Fiorotto, Marta -|
Submitted to: Animal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: April 5, 2010
Publication Date: May 21, 2010
Repository URL: http://journals.cambridge.org/repo_A79Kov2F
Citation: Davis, T.A., Suryawan, A., Orellana, R.A., Fiorotto, M.L., Burrin, D.G. 2010. Amino acids and insulin are regulators of muscle protein synthesis in neonatal pigs. Animal. 4(11):1790-1796. Interpretive Summary: In the period between birth and weaning (neonatal period), the animal can grow extremely fast. This is important for the long-term well-being of the animal. During this period, protein originated from food is efficiently used to make body protein mass such as skeletal muscle. Thus, proper feeding is crucial to achieve this goal. One of the reasons for the efficiency is that during the neonatal period the machineries required to make protein is very active and they determine animal growth. These results show us that early application of "good nutrition" is critical in achieving normal growth and lasting effects in humans.
Technical Abstract: The stage of development between birth and weaning in mammals is a period of very rapid growth that is crucial for the long-term well-being of the animal. The rate of protein deposition in neonatal animals is very high because dietary protein is efficiently utilized to increase body protein mass. Our studies in neonatal pigs have shown that this high efficiency of protein deposition is largely due to the marked increase in protein synthesis after feeding, and this response is particularly profound in the skeletal muscle. The enhanced stimulation of muscle protein synthesis in neonates after feeding is independently mediated by the rise in insulin and amino acids, and this response declines with age. Intracellular signaling components that respond to the postprandial rise in amino acids and insulin, have been identified and their activation has been shown to be elevated in skeletal muscle of neonatal pigs after a meal and to decrease with development. The enhanced activation of these components in the amino acid and insulin signaling pathways in neonatal muscle contributes to the high rate of muscle protein synthesis and rapid gain in skeletal muscle mass in newborn pigs, which are essential determinants of efficient growth during development.