title: Feeding rapidly stimulates protein synthesis in skeletal muscle of neonatal pigs by enhancing translation initiation.
abstract: Food consumption increases protein synthesis in most tissues by promoting translation initiation, and in the neonate, this increase is greatest in skeletal muscle. In this study, we aimed to identify the currently unknown time course of changes in the rate of protein synthesis and the activation of factors involved in translation in neonatal muscle after a meal. After overnight food deprivation, 36 5- to 7-d-old piglets were administered a nutritionally complete bolus i.g. meal and were killed immediately before or 30, 60, 90, 120, or 240 min later. The increase in skeletal muscle protein synthesis peaked 30 min after the meal and this was sustained through 120 min, returning to baseline thereafter. The relative proportion of polysomes to nonpolysomes was higher only after 30 min. Protein kinase B phosphorylation peaked 30 min after feeding and returned to baseline by 90 min. The phosphorylation of mammalian target of rapamycin, eukaryotic initiation factor (eIF) 4E binding protein (4E-BP1), ribosomal protein S6, and eIF4G was increased within 30 min of feeding and persisted through 120 min, but all had returned to baseline by 240 min. The association of 4E-BP1.eIF4E was reduced and eIF4E.eIF4G increased 30 min after receiving a meal, remaining so for 120 min, before returning to baseline at 240 min. Thus, in neonates, food consumption rapidly increased skeletal muscle protein synthesis by enhancing translation initiation and this increase was sustained for at least 120 min after the meal but returned to baseline by 240 min after the feeding.
authors.affiliation: USDA/Agriculture Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: Fiona A
authors.initials: FA
authors.lastname: Wilson
authors.forename: Agus
authors.initials: A
authors.lastname: Suryawan
authors.forename: Renán A
authors.initials: RA
authors.lastname: Orellana
authors.forename: Scot R
authors.initials: SR
authors.lastname: Kimball
authors.forename: Maria C
authors.initials: MC
authors.lastname: Gazzaneo
authors.forename: Hanh V
authors.initials: HV
authors.lastname: Nguyen
authors.forename: Marta L
authors.initials: ML
authors.lastname: Fiorotto
authors.forename: Teresa A
authors.initials: TA
authors.lastname: Davis
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001786:Blood Glucose; D005508:Food Deprivation; D041941:Milk Substitutes / Q000494:pharmacology*; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism*; D018482:Muscle, Skeletal / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000502:physiology*; D013552:Swine; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D009124:Muscle Proteins
references.citation: Endocrinology. 2005 Mar;146(3):1328-37
references.pmid: 15576463
references.citation: Am J Physiol. 1993 Aug;265(2 Pt 2):R334-40
references.pmid: 8368387
references.citation: Eur J Biochem. 2002 Nov;269(22):5360-8
references.pmid: 12423334
references.citation: Mol Cell. 2008 Apr 25;30(2):214-26
references.pmid: 18439900
references.citation: Am J Physiol. 1996 May;270(5 Pt 1):E802-9
references.pmid: 8967468
references.citation: J Biol Chem. 2005 Mar 4;280(9):7570-80
references.pmid: 15591312
references.citation: Proc Natl Acad Sci U S A. 1994 May 10;91(10):4441-5
references.pmid: 8183928
references.citation: Oncogene. 2006 Oct 16;25(48):6347-60
references.pmid: 17041621
references.citation: J Nutr. 2002 Oct;132(10):3228S-33S
references.pmid: 12368423
references.citation: Am J Physiol Endocrinol Metab. 2002 Apr;282(4):E880-90
references.pmid: 11882508
references.citation: Biochem Biophys Res Commun. 2004 Jan 9;313(2):429-36
references.pmid: 14684180
references.citation: Am J Physiol. 1999 Jul;277(1):E103-9
references.pmid: 10409133
references.citation: Genes Dev. 2001 Apr 1;15(7):807-26
references.pmid: 11297505
references.citation: Am J Physiol Endocrinol Metab. 2007 Jul;293(1):E188-96
references.pmid: 17389711
references.citation: Am J Physiol Endocrinol Metab. 2006 Oct;291(4):E849-59
references.pmid: 16757550
references.citation: Am J Physiol Endocrinol Metab. 2005 May;288(5):E914-21
references.pmid: 15644455
references.citation: Am J Physiol Endocrinol Metab. 2000 Nov;279(5):E1080-7
references.pmid: 11052963
references.citation: J Nutr. 2005 Jun;135(6):1430-7
references.pmid: 15930448
references.citation: Genes Dev. 2004 Aug 15;18(16):1926-45
references.pmid: 15314020
references.citation: Am J Physiol Endocrinol Metab. 2006 Apr;290(4):E612-21
references.pmid: 16278252
references.citation: J Nutr. 2006 Sep;136(9):2284-90
references.pmid: 16920842
references.citation: J Nutr. 2005 Jun;135(6):1374-81
references.pmid: 15930440
references.citation: Dev Cell. 2007 Apr;12(4):487-502
references.pmid: 17419990
references.citation: Am J Physiol Endocrinol Metab. 2007 Aug;293(2):E595-603
references.pmid: 17551002
references.citation: Oncogene. 2006 Oct 16;25(48):6361-72
references.pmid: 17041622
references.citation: Am J Physiol Endocrinol Metab. 2006 Feb;290(2):E225-33
references.pmid: 16144813
references.citation: Semin Cell Dev Biol. 2005 Feb;16(1):3-12
references.pmid: 15659334
references.citation: Am J Physiol Endocrinol Metab. 2001 Nov;281(5):E908-15
references.pmid: 11595645
references.citation: Am J Physiol Endocrinol Metab. 2003 Jan;284(1):E110-9
references.pmid: 12388131
references.citation: Cell. 2002 Jul 26;110(2):163-75
references.pmid: 12150925
references.citation: Trends Biochem Sci. 2006 Jun;31(6):342-8
references.pmid: 16679021
references.citation: J Biol Chem. 1985 Jun 10;260(11):6677-83
references.pmid: 2581958
references.citation: Oncogene. 2006 Oct 16;25(48):6416-22
references.pmid: 17041626
references.citation: J Nutr. 2006 Jan;136(1 Suppl):227S-31S
references.pmid: 16365087
references.citation: Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14930-5
references.pmid: 9405716
references.citation: Am J Physiol Endocrinol Metab. 2006 Jul;291(1):E80-9
references.pmid: 16760336
references.citation: Am J Physiol. 1989 Nov;257(5 Pt 2):R1141-6
references.pmid: 2480066
references.citation: Biochem J. 1980 Nov 15;192(2):719-23
references.pmid: 6786283
references.citation: Am J Physiol. 1998 Oct;275(4):E602-9
references.pmid: 9755078
references.citation: Mol Cell. 2006 Apr 21;22(2):159-68
references.pmid: 16603397
references.citation: Am J Physiol Endocrinol Metab. 2000 Dec;279(6):E1226-34
references.pmid: 11093908
references.citation: Am J Physiol Endocrinol Metab. 2007 Jun;292(6):E1647-55
references.pmid: 17284572
references.citation: Am J Physiol Endocrinol Metab. 2007 Dec;293(6):E1597-605
references.pmid: 17878222
references.citation: J Biol Chem. 2006 Aug 25;281(34):24293-303
references.pmid: 16798736
references.citation: J Nutr. 2007 Aug;137(8):1857-62
references.pmid: 17634255
references.citation: Am J Physiol Endocrinol Metab. 2008 Oct;295(4):E868-75
references.pmid: 18682538
references.citation: Am J Physiol Endocrinol Metab. 2003 Jul;285(1):E40-53
references.pmid: 12637260