Treatment with TNF-alpha and IFN-gamma alters the activation of SER/THR protein kinases and the metabolic response to IGF-I in mouse c2c12 myogenic cells.
The aim of this study was to compare the effects of TNF-alpha, IL-1beta and IFN-gamma on the activation of protein kinase B (PKB), p70(S6k), mitogen-activated protein kinase (MAPK) and p90( rsk ), and on IGF-I-stimulated glucose uptake and protein synthesis in mouse C2C12 myotubes. 100 nmol/l IGF-I stimulated glucose uptake in C2C12 myotubes by 198.1% and 10 ng/ml TNF-alpha abolished this effect. Glucose uptake in cells differentiated in the presence of 10 ng/ml IFN-gamma increased by 167.2% but did not undergo significant further modification upon the addition of IGF-I. IGF-I increased the rate of protein synthesis by 249.8%. Neither TNF-alpha nor IFN-gamma influenced basal protein synthesis, but both cytokines prevented the IGF-I effect. 10 ng/ml IL-1beta did not modify either the basal or IGF-I-dependent glucose uptake and protein synthesis. With the exception of TNF-alpha causing an 18% decrease in the level of PKB protein, the cellular levels of PKB, p70(S6k), p42(MAPK), p44(MAPK) and p90( rsk ) were not affected by the cytokines. IGF-I caused the phosphorylation of PKB (an approximate 8-fold increase above the basal value after 40 min of IGF-I treatment), p42(MAPK) (a 2.81-fold increase after 50 min), and the activation of p70(S6k) and p90( rsk ), manifesting as gel mobility retardation. In cells differentiated in the presence of TNF-alpha or IFN-gamma, this IGF-I-mediated PKB and p70(S6k) phosphorylation was significantly diminished, and the increase in p42(MAPK) and p90( rsk ) phosphorylation was prevented. The basal p42(MAPK) phosphorylation in C2C12 cells treated with IFN-gamma was high and comparable with the activation of this kinase by IGF-I. Pretreatment of myogenic cells with IL-1beta did not modify the IGF-I-stimulated phosphorylation of PKB, p70(S6k), p42(MAPK) and p90( rsk ).


CONCLUSIONS
i) TNF-alpha and IFN-gamma, but not IL-1beta, if present in the extracellular environment during C2C12 myoblast differentiation, prevent the stimulatory action of IGF-I on protein synthesis. ii) TNF-alpha- and IFN-gamma-induced IGF-I resistance of protein synthesis could be associated with the decreased phosphorylation of PKB and p70(S6k). iii) The activation of glucose uptake in C2C12 myogenic cells treated with IFN-gamma is PKB independent. iv) The similar effects of TNF-alpha and IFN-gamma on the signalling and action of IGF-I on protein synthesis in myogenic cells could suggest the involvement of both of these cytokines in protein loss in skeletal muscle.
Grzelkowska-Kowalczyk
Katarzyna
K
Department of Physiological Sciences, Faculty of Veterinary Medicine, Warsaw University of Life Sciences (SGGW), Nowoursynowska 159, 02-776, Warsaw, Poland. k_grzel_kow@poczta.fm
Wieteska-Skrzeczyńska
Wioletta
W
D000818:Animals; D002460:Cell Line; D005947:Glucose / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D007371:Interferon-gamma / Q000494:pharmacology*; D053583:Interleukin-1beta / Q000494:pharmacology; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D018485:Muscle Fibers, Skeletal / Q000201:enzymology* / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D038762:Ribosomal Protein S6 Kinases, 70-kDa / Q000378:metabolism; D038744:Ribosomal Protein S6 Kinases, 90-kDa / Q000378:metabolism; D015398:Signal Transduction; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D007334:Insulin-Like Growth Factor I; D007371:Interferon-gamma; D017346:Protein Serine-Threonine Kinases; D051057:Proto-Oncogene Proteins c-akt; D038762:Ribosomal Protein S6 Kinases, 70-kDa; D038744:Ribosomal Protein S6 Kinases, 90-kDa; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D005947:Glucose
Pol J Vet Sci. 2005;8(3):241-50
16180586
Am J Physiol. 1999 May;276(5):R1327-33
10233023
Cell Signal. 2005 Nov;17(11):1333-42
16125053
Nutr Rev. 2002 Feb;60(2):39-51
11852969
Am J Physiol Endocrinol Metab. 2000 Jul;279(1):E196-205
10893340
Endocrinology. 2003 Jul;144(7):2988-96
12810554
Mech Ageing Dev. 2003 Apr;124(4):495-502
12714258
J Clin Endocrinol Metab. 2009 Jan;94(1):294-9
18854397
J Clin Invest. 2004 Aug;114(3):370-8
15286803
Am J Physiol Endocrinol Metab. 2007 Feb;292(2):E501-12
17003238
J Cell Biochem. 2005 Feb 1;94(2):419-31
15534870
Am J Physiol Endocrinol Metab. 2005 Jul;289(1):E95-104
15701678
Muscle Nerve. 2005 Mar;31(3):339-48
15751123
J Biol Chem. 2001 Jul 13;276(28):25990-6
11352919
Endocrinology. 2005 Jun;146(6):2726-35
15746249
Cytokine. 2006 Aug;35(3-4):154-8
17005412
Am J Physiol Endocrinol Metab. 2002 Dec;283(6):E1279-90
12388149
Exp Cell Res. 2004 Mar 10;294(1):223-35
14980516
Nat Cell Biol. 2001 Nov;3(11):1009-13
11715022
Br J Cancer. 2001 Apr 6;84(7):946-50
11286475
QJM. 2005 Jan;98(1):1-6
15625348
Metabolism. 2002 Sep;51(9):1171-9
12200763
Clin Exp Immunol. 2003 Oct;134(1):107-10
12974762
Nat Genet. 2001 Feb;27(2):195-200
11175789
BMC Immunol. 2008 Jul 31;9:43
18671865
Am J Physiol Cell Physiol. 2007 Dec;293(6):C1947-52
17928538
Biochimie. 2005 Jan;87(1):99-109
15733744
Pol J Vet Sci. 2006;9(1):1-10
16573269
Am J Physiol Endocrinol Metab. 2008 Feb;294(2):E241-50
17971516
Muscle Nerve. 2003 Dec;28(6):659-82
14639580
J Anim Sci. 2008 Apr;86(14 Suppl):E84-93
18192560
Trends Immunol. 2005 Oct;26(10):535-42
16109502
Biochim Biophys Acta. 2002 Jan 30;1542(1-3):66-72
11853880
Hypertens Res. 2003 May;26(5):389-96
12887130
Intensive Care Med. 2005 Oct;31(10):1415-9
16132884
J Appl Physiol (1985). 2001 Jun;90(6):2166-71
11356779
Nutrition. 2000 Oct;16(10):1015-8
11054610
Nature. 2002 Nov 21;420(6913):333-6
12447443
J Biol Chem. 2004 Apr 23;279(17):17070-8
14764603
Growth Horm IGF Res. 2002 Apr;12(2):84-90
12175645
Endocrinology. 2003 May;144(5):1770-9
12697682
Cancer. 2003 Mar 1;97(5):1211-6
12599227
Int Immunol. 2000 Sep;12(9):1329-35
10967028