Feeding rapidly stimulates protein synthesis in skeletal muscle of neonatal pigs by enhancing translation initiation.
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.
Wilson
Fiona A
FA
USDA/Agriculture Research Service Children's Nutrition Research Center, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
Suryawan
Agus
A
Orellana
Renán A
RA
Kimball
Scot R
SR
Gazzaneo
Maria C
MC
Nguyen
Hanh V
HV
Fiorotto
Marta L
ML
Davis
Teresa A
TA
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
D001786:Blood Glucose; D009124:Muscle Proteins
Endocrinology. 2005 Mar;146(3):1328-37
15576463
Am J Physiol. 1993 Aug;265(2 Pt 2):R334-40
8368387
Eur J Biochem. 2002 Nov;269(22):5360-8
12423334
Mol Cell. 2008 Apr 25;30(2):214-26
18439900
Am J Physiol. 1996 May;270(5 Pt 1):E802-9
8967468
J Biol Chem. 2005 Mar 4;280(9):7570-80
15591312
Proc Natl Acad Sci U S A. 1994 May 10;91(10):4441-5
8183928
Oncogene. 2006 Oct 16;25(48):6347-60
17041621
J Nutr. 2002 Oct;132(10):3228S-33S
12368423
Am J Physiol Endocrinol Metab. 2002 Apr;282(4):E880-90
11882508
Biochem Biophys Res Commun. 2004 Jan 9;313(2):429-36
14684180
Am J Physiol. 1999 Jul;277(1):E103-9
10409133
Genes Dev. 2001 Apr 1;15(7):807-26
11297505
Am J Physiol Endocrinol Metab. 2007 Jul;293(1):E188-96
17389711
Am J Physiol Endocrinol Metab. 2006 Oct;291(4):E849-59
16757550
Am J Physiol Endocrinol Metab. 2005 May;288(5):E914-21
15644455
Am J Physiol Endocrinol Metab. 2000 Nov;279(5):E1080-7
11052963
J Nutr. 2005 Jun;135(6):1430-7
15930448
Genes Dev. 2004 Aug 15;18(16):1926-45
15314020
Am J Physiol Endocrinol Metab. 2006 Apr;290(4):E612-21
16278252
J Nutr. 2006 Sep;136(9):2284-90
16920842
J Nutr. 2005 Jun;135(6):1374-81
15930440
Dev Cell. 2007 Apr;12(4):487-502
17419990
Am J Physiol Endocrinol Metab. 2007 Aug;293(2):E595-603
17551002
Oncogene. 2006 Oct 16;25(48):6361-72
17041622
Am J Physiol Endocrinol Metab. 2006 Feb;290(2):E225-33
16144813
Semin Cell Dev Biol. 2005 Feb;16(1):3-12
15659334
Am J Physiol Endocrinol Metab. 2001 Nov;281(5):E908-15
11595645
Am J Physiol Endocrinol Metab. 2003 Jan;284(1):E110-9
12388131
Cell. 2002 Jul 26;110(2):163-75
12150925
Trends Biochem Sci. 2006 Jun;31(6):342-8
16679021
J Biol Chem. 1985 Jun 10;260(11):6677-83
2581958
Oncogene. 2006 Oct 16;25(48):6416-22
17041626
J Nutr. 2006 Jan;136(1 Suppl):227S-31S
16365087
Proc Natl Acad Sci U S A. 1997 Dec 23;94(26):14930-5
9405716
Am J Physiol Endocrinol Metab. 2006 Jul;291(1):E80-9
16760336
Am J Physiol. 1989 Nov;257(5 Pt 2):R1141-6
2480066
Biochem J. 1980 Nov 15;192(2):719-23
6786283
Am J Physiol. 1998 Oct;275(4):E602-9
9755078
Mol Cell. 2006 Apr 21;22(2):159-68
16603397
Am J Physiol Endocrinol Metab. 2000 Dec;279(6):E1226-34
11093908
Am J Physiol Endocrinol Metab. 2007 Jun;292(6):E1647-55
17284572
Am J Physiol Endocrinol Metab. 2007 Dec;293(6):E1597-605
17878222
J Biol Chem. 2006 Aug 25;281(34):24293-303
16798736
J Nutr. 2007 Aug;137(8):1857-62
17634255
Am J Physiol Endocrinol Metab. 2008 Oct;295(4):E868-75
18682538
Am J Physiol Endocrinol Metab. 2003 Jul;285(1):E40-53
12637260