QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Wykes, L. J. Articles by Jahoor, F. Search for Related Content PubMed PubMed Citation Articles by Wykes, L. J. Articles by Jahoor, F.

Chronic Low Protein Intake Reduces Tissue Protein Synthesis in a Pig Model of Protein Malnutrition^1,2,

USDA/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030

To determine the effect of severe chronic protein deficiency on protein synthesis in different tissues and total protein in plasma, and on plasma biochemical constituents involved in amino acid metabolism, we fed diets containing either 20 or 3% protein to two groups of four age-matched piglets. After consuming the diets for 8 wk, the pigs received a primed-constant infusion of ²H₃-leucine for 8 h to measure the fractional synthesis rates (FSR) of tissue protein and total protein in plasma. Plasma urea and amino acid concentrations, particularly indispensable amino acids, were significantly lower in protein-deficient pigs. Fractional protein synthesis rates were lower in skin by 66% (P < 0.01), in jejunal mucosa by 50% (P < 0.05), in masseter muscle by 40% (P < 0.05), and in liver by 25% (P < 0.02); the fractional synthesis rate of the longissimus muscle was not different than controls. Although plasma protein concentration was significantly (P < 0.01) lower in protein-deficient pigs, the fractional synthesis rate of the total intravascular plasma protein pool was not different. We conclude that adaptation to a low protein diet involves a reduction in the rate of protein synthesis in most body tissues, with the most marked changes occurring in skin and intestine, two tissues which frequently exhibit severe functional impairment in protein malnutrition.

KEY WORDS: • protein deficiency • tissue protein synthesis • stable isotope • pigs

¹ Supported by federal funds from the U.S. Department of Agriculture, Agricultural Research Service under Cooperative agreement number 58-6250-1-003, and by National Institutes of Health Grant DK41764. This is a publication of the U.S. Department of Agriculture/Agricultural Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine and Texas Children's Hospital, Houston, TX. The contents of this publication do not necessarily reflect the views or policies of the U.S. Department of Agriculture, nor does mention of trade names, commercial products or organizations imply endorsement by the U.S. government.

² The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 USC section 1734 solely to indicate this fact.

³ Current address: School of Dietetics and Human Nutrition, McGill University, Macdonald Campus, Montreal, Canada.

⁴ To whom correspondence and reprint requests should be addressed.

Manuscript received 13 September 1995. Revision accepted 16 January 1996.

This article has been cited by other articles:

				K. Bergeron, P. Julien, T. A. Davis, A. Myre, and M. C. Thivierge Long-chain n-3 fatty acids enhance neonatal insulin-regulated protein metabolism in piglets by differentially altering muscle lipid composition J. Lipid Res., November 1, 2007; 48(11): 2396 - 2410. [Abstract] [Full Text] [PDF]

				G. Diaz-Llano and T. K. Smith The effects of feeding grains naturally contaminated with Fusarium mycotoxins with and without a polymeric glucomannan adsorbent on lactation, serum chemistry, and reproductive performance after weaning of first-parity lactating sows J Anim Sci, June 1, 2007; 85(6): 1412 - 1423. [Abstract] [Full Text] [PDF]

				F. Guay and N. L. Trottier Muscle growth and plasma concentrations of amino acids, insulin-like growth factor-I, and insulin in growing pigs fed reduced-protein diets J Anim Sci, November 1, 2006; 84(11): 3010 - 3019. [Abstract] [Full Text] [PDF]

				F. Guay, S. M. Donovan, and N. L. Trottier Biochemical and morphological developments are partially impaired in intestinal mucosa from growing pigs fed reduced-protein diets supplemented with crystalline amino acids J Anim Sci, July 1, 2006; 84(7): 1749 - 1760. [Abstract] [Full Text] [PDF]

				M. Z. Fan, L. I. Chiba, P. D. Matzat, X. Yang, Y. L. Yin, Y. Mine, and H. H. Stein Measuring synthesis rates of nitrogen-containing polymers by using stable isotope tracers J Anim Sci, April 1, 2006; 84(13_suppl): E79 - E. [Abstract] [Full Text] [PDF]

				B. Stoll, P. T. Price, P. J. Reeds, X. Chang, J. F. Henry, J. B. van Goudoever, J. J. Holst, and D. G. Burrin Feeding an Elemental Diet vs a Milk-Based Formula Does Not Decrease Intestinal Mucosal Growth in Infant Pigs JPEN J Parenter Enteral Nutr, January 1, 2006; 30(1): 32 - 39. [Abstract] [Full Text] [PDF]

				P. R. Afolabi, F. Jahoor, N. R. Gibson, and A. A. Jackson Response of hepatic proteins to the lowering of habitual dietary protein to the recommended safe level of intake Am J Physiol Endocrinol Metab, August 1, 2004; 287(2): E327 - E330. [Abstract] [Full Text] [PDF]

				M. Coeffier, S. Claeyssens, B. Hecketsweiler, A. Lavoinne, P. Ducrotte, and P. Dechelotte Enteral glutamine stimulates protein synthesis and decreases ubiquitin mRNA level in human gut mucosa Am J Physiol Gastrointest Liver Physiol, July 7, 2003; 285(2): G266 - G273. [Abstract] [Full Text] [PDF]