Page Banner

United States Department of Agriculture

Agricultural Research Service

Research Project: MOLECULAR, CELLULAR, AND REGULATORY ASPECTS OF NUTRITIONAL METABOLISM DURING CHILDHOOD DEVELOPMENT

Location: Children's Nutrition Research Center

Title: Intermittent bolus feeding has a greater stimulatory effect on protein synthesis in skeletal muscle than continuous feeding in neonatal pigs

Authors
item Gazzaneo, Maria -
item Suryawan, Agus -
item Orellana, Renan -
item Torrazza, Roberto -
item El-Kadi, Samer -
item Wilson, Fiona -
item Kimbal, Scot -
item Srivastava, Neeraj -
item Nguyen, Hanh -
item Fiorotto, Marta -
item Davis, Teresa -

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: September 21, 2011
Publication Date: October 19, 2011
Citation: Gazzaneo, M.C., Suryawan, A., Orellana, R.A., Torrazza, R.M., El-Kadi, S.W., Wilson, F.A., Kimbal, S.R., Srivastava, N., Nguyen, H.V., Fiorotto, M.L., Davis, T.A. 2011. Intermittent bolus feeding has a greater stimulatory effect on protein synthesis in skeletal muscle than continuous feeding in neonatal pigs. Journal of Nutrition. 141(12):2152-2158.

Interpretive Summary: Over 7% of all newborn babies born in the U.S. are of low birth weight and the regulation of protein synthesis is critical for this group. Our study aimed to look at oral stomach tube feeding that is used either contiuous or intermittent bolus delivery. The goal of the study was to compare the impact of different feeding strategies on muscle protein synthesis. Our results showed that muscle protein synthesis was stimulated by feeding and the greatest response occurred after a meal. These results suggest that in neonates, intermittent bolus feeding enhances muscle protein synthesis to a greater extent than continuous feeding by eliciting a pulsatile pattern of amino acid- and insulin-induced translation initiation. This is important for medical professionals treating newborn infants that require tube feeding.

Technical Abstract: Orogastric tube feeding, using either continuous or intermittent bolus delivery, is common in infants for whom normal feeding is contraindicated. To compare the impact of different feeding strategies on muscle protein synthesis, after withholding food overnight, neonatal pigs received a complete formula orally as a bolus feed every 4 h or were continuously fed. Protein synthesis rate and translational mechanisms in skeletal muscle were examined after 0, 24, and 25.5 h. Plasma amino acid and insulin concentrations increased minimally and remained constant in continuously fed compared to feed-deprived pigs; however, the pulsatile meal feeding pattern was mimicked in bolus-fed pigs. Muscle protein synthesis was stimulated by feeding and the greatest response occurred after a bolus meal. Bolus but not continuous feeds increased polysome aggregation, the phosphorylation of protein kinase B, tuberous sclerosis complex 2, proline-rich Akt substrate of 40 kDa, eukaryotic initiation factor (eIF) 4E binding protein (4EBP1), and rp S6 kinase and enhanced dissociation of the 4EBP1 / eIF4E complex and formation of the eIF4E / eIF4G complex compared to feed deprivation (P < 0.05). Activation of insulin receptor substrate-1, regulatory associated protein of mammalian target of rapamycin, AMP-activated protein kinase, eukaryotic elongation factor 2, and eIF2alpha phosphorylation were unaffected by either feeding modality. These results suggest that in neonates, intermittent bolus feeding enhances muscle protein synthesis to a greater extent than continuous feeding by eliciting a pulsatile pattern of amino acid- and insulin-induced translation initiation.

Last Modified: 8/27/2014
Footer Content Back to Top of Page