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

This Article Full Text 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 Papet, I. Articles by Obled, C. Search for Related Content PubMed PubMed Citation Articles by Papet, I. Articles by Obled, C. Pubmed/NCBI databases Medline Plus Health Information E. Coli Infections

---

Nutritional Immunology

Bacterial Infection Affects Protein Synthesis in Primary Lymphoid Tissues and Circulating Lymphocytes of Rats¹

Isabelle Papet², Benoît Ruot, Denis Breuillé^*, Stéphane Walrand, Marie-Chantal Farges, Marie-Paule Vasson and Christiane Obled

Unité de Nutrition et Métabolisme Protéique, INRA Theix, 63122 Saint-Genès-Champanelle, France; ^* Nestlé Research Center, 1000 Lausanne 26, Switzerland; Laboratoire de Biochimie, Biologie Moléculaire et Nutrition, Faculté de Pharmacie, 63001 Clermont-Ferrand, France

²To whom correspondence should be addressed. E-mail: papet{at}clermont.inra.fr.

Bacterial infection alters whole-body protein homeostasis. Although immune cells are of prime importance for host defense, the effect of sepsis on their protein synthesis rates is poorly documented. We analyzed protein synthesis rates in rat primary lymphoid tissues and circulating lymphocytes after infection. Male Sprague-Dawley rats were studied 1, 2, 6 or 10 d after an intravenous injection of live Escherichia coli. Control healthy rats consumed food ad libitum (d 0) or were pair-fed to infected rats. Protein synthesis was quantified using a flooding dose of L-(4,4,4-²H₃)valine. Sepsis induced a delayed increase in total blood leukocytes and a rapid and persistent inversion of the counts. Basal fractional rates of protein synthesis (ks) were 117, 73 and 29%/d in bone marrow, thymus and circulating lymphocytes, respectively. Pair-feeding strongly depressed the absolute protein synthesis rates (ASR) of bone marrow (d 2 and 10) and thymus (d 2–10). The infection per se increased bone marrow, thymus and circulating lymphocyte ks but at various postinfection times. It decreased bone marrow (d 1) and thymus (d 1 and 2) ASR but increased lymphocyte (d 2 and 10) and bone marrow (d 10) ASR. Our results reflect the deleterious effect of anorexia on primary lymphoid tissues. The host defense against bacterial infection exhibited time- and tissue-dependent modifications of protein synthesis, indicating that blood lymphocyte protein data are not representative of the immune system as a whole. Optimization of nutritional supports would be facilitated by including protein synthesis measurements of the immune system.

KEY WORDS: • rats • sepsis • protein synthesis • lymphoid tissues • circulating lymphocytes

This article has been cited by other articles:

				S. Walrand, C. Guillet, P. Gachon, P. Rousset, C. Giraudet, M.-P. Vasson, and Y. Boirie Protein synthesis rates of human PBMC and PMN can be determined simultaneously in vivo by using small blood samples Am J Physiol Cell Physiol, June 1, 2004; 286(6): C1474 - C1478. [Abstract] [Full Text] [PDF]

				I. Papet, D. Dardevet, C. Sornet, F. Bechereau, J. Prugnaud, C. Pouyet, and C. Obled Acute Phase Protein Levels and Thymus, Spleen and Plasma Protein Synthesis Rates Differ in Adult and Old Rats J. Nutr., January 1, 2003; 133(1): 215 - 219. [Abstract] [Full Text] [PDF]