The c-Jun N-Terminal Kinase Mediates the Induction of Oxidative Stress and Insulin Resistance by Palmitate and Toll-like Receptor 2 and 4 Ligands in 3T3-L1 Adipocytes

Abstract

Saturated fatty acids (SFAs) are known to induce inflammation and insulin resistance in adipocytes through toll-like receptor-4 (Tlr4) signaling, but the mechanisms are not well delineated. Furthermore, the potential roles of Tlr2 and the c-Jun N-terminal kinase (JNK) in inflammation in adipocytes have not been investigated. We demonstrated that palmitate, lipopolysaccharide (LPS), and the toll-like receptor-2 (Tlr2) agonist, zymosan A (ZymA), induced insulin resistance in a time- and dose-dependent manner in 3T3-L1 adipocytes. Corresponding with the reduction of insulin sensitivity was an increased expression of IL-6, as well as activation of the proinflammatory transcription factors, nuclear factor kappa B, and activator protein-1. Reactive oxygen species (ROS) accumulation was also observed in palmitate and Tlr agonist treated adipocytes. The JNK inhibitor, SP600125, attenuated insulin resistance mediated by SFA and Tlr agonists, which corresponded with a diminished proinflammatory response and reduced ROS accumulation. Collectively, these results demonstrated Tlr2 involvement in adipocyte inflammation and therefore implicated the receptor as a potential target for SFA. Moreover, activation of JNK also appeared to be essential to Tlr2-, as well as Tlr4-induced insulin resistance and oxidative stress.

Key words

adipose tissue - obesity - cytokines - chemokines

References

• 1 Neels JG, Olefsky JM. Inflamed fat: what starts the fire?.  J Clin Invest. 2006;  116 33-35
• 2 Shoelson SE, Lee J, Goldfine AB. Inflammation and insulin resistance.  J Clin Invest. 2006;  116 1793-1801
• 3 Takahashi K, Yamaguchi S, Shimoyama T, Seki H, Miyokawa K, Katsuta H, Tanaka T, Yoshimoto K, Ohno H, Nagamatsu S, Ishida H. JNK- and I{kappa}B-dependent pathways regulate MCP-1, but not adiponectin release from artificially hypertrophied 3T3-L1 adipocytes preloaded with palmitate in vitro.  Am J Physiol Endocrinol Metab. 2008;  294 E898-E909
• 4 Andersen K, Pedersen BK. The role of inflammation in vascular insulin resistance with focus on IL-6.  Horm Metab Res. 2008;  40 635-639
• 5 Yudkin JS. Inflammation, obesity, and the metabolic syndrome.  Horm Metab Res. 2007;  39 707-709
• 6 Ohmura E, Hosaka D, Yazawa M, Tsuchida A, Tokunaga M, Ishida H, Minagawa S, Matsuda A, Imai Y, Kawazu S, Sato T. Association of free fatty acids (FFA) and tumor necrosis factor-alpha (TNF-alpha) and insulin-resistant metabolic disorder.  Horm Metab Res. 2007;  39 212-217
• 7 Jove M, Planavila A, Laguna JC, Vazquez-Carrera M. Palmitate-induced interleukin 6 production is mediated by protein kinase C and nuclear-factor kappaB activation and leads to glucose transporter 4 down-regulation in skeletal muscle cells.  Endocrinology. 2005;  146 3087-3095
• 8 Jove M, Planavila A, Sanchez RM, Merlos M, Laguna JC, Vazquez-Carrera M. Palmitate induces tumor necrosis factor-alpha expression in C2C12 skeletal muscle cells by a mechanism involving protein kinase C and nuclear factor-kappaB activation.  Endocrinology. 2006;  147 552-561
• 9 Sinha S, Perdomo G, Brown NF, O’Doherty RM. Fatty acid-induced insulin resistance in L6 myotubes is prevented by inhibition of activation and nuclear localization of nuclear factor kappa B.  J Biol Chem. 2004;  279 41294-41301
• 10 Weigert C, Brodbeck K, Staiger H, Kausch C, Machicao F, Haring HU, Schleicher ED. Palmitate, but not unsaturated fatty acids, induces the expression of interleukin-6 in human myotubes through proteasome-dependent activation of nuclear factor-kappaB.  J Biol Chem. 2004;  279 23942-23952
• 11 Suganami T, Nishida J, Ogawa Y. A paracrine loop between adipocytes and macrophages aggravates inflammatory changes: role of free fatty acids and tumor necrosis factor alpha.  Arterioscler Thromb Vasc Biol. 2005;  25 2062-2068
• 12 Ajuwon KM, Spurlock ME. Palmitate activates the NF-kappaB transcription factor and induces IL-6 and TNFalpha expression in 3T3-L1 adipocytes.  J Nutr. 2005;  135 1841-1846
• 13 Subauste AR, Burant CF. Role of FoxO1 in FFA-induced oxidative stress in adipocytes.  Am J Physiol Endocrinol Metab. 2007;  293 E159-E164
• 14 Furukawa S, Fujita T, Shimabukuro M, Iwaki M, Yamada Y, Nakajima Y, Nakayama O, Makishima M, Matsuda M, Shimomura I. Increased oxidative stress in obesity and its impact on metabolic syndrome.  J Clin Invest. 2004;  114 1752-1761
• 15 Houstis N, Rosen ED, Lander ES. Reactive oxygen species have a causal role in multiple forms of insulin resistance.  Nature. 2006;  440 944-948
• 16 Joshi-Barve S, Barve SS, Amancherla K, Gobejishvili L, Hill D, Cave M, Hote P, MacClain CJ. Palmitic acid induces production of proinflammatory cytokine interleukin-8 from hepatocytes.  Hepatology. 2007;  46 823-830
• 17 Song MJ, Kim KH, Yoon JM, Kim JB. Activation of Toll-like receptor 4 is associated with insulin resistance in adipocytes.  Biochem Biophys Res Commun. 2006;  346 739-745
• 18 Suganami T, Mieda T, Itoh M, Shimoda Y, Kamei Y, Ogaway Y. Attenuation of obesity-induced adipose tissue inflammation in C3H/HeJ mice carrying a Toll-like receptor 4 mutation.  Biochem Biophys Res Commun. 2007;  354 45-49
• 19 Shi H, Kokoeva MV, Inouyi K, Tzameli I, Yin H, Flier JS. TLR4 links innate immunity and fatty acid-induced insulin resistance.  J Clin Invest. 2006;  116 3015-3025
• 20 Suganami T, Tanimoto-Koyama K, Nishida J, Itoh M, Yuam, Mizuarai S, Kotami H, Yamaoka S, Miyake K, Aoe S, Kamei Y, Ogawa Y. Role of the toll-like receptor 4/NF-{kappa}B pathway in saturated fatty acid-induced inflammatory changes in the interaction between adipocytes and macrophages.  Arterioscler Thromb Vasc Biol. 2007;  27 84-91
• 21 Tsukumo DM, Carvalho-Filho MA, Carvalheira JB, Prada PO, Hirabara SM, Schenka AA, Aranjo EP, Vassallo J, Curi R, Velloso LA, Saad MJ. Loss-of-function mutation in TLR4 prevents diet-induced obesity and insulin resistance.  Diabetes. 2007;  56 1986-1998
• 22 Lee JY, Sohn KH, Rhee SH, Hwang D. Saturated fatty acids, but not unsaturated fatty acids, induce the expression of cyclooxygenase-2 mediated through Toll-like receptor 4.  J Biol Chem. 2001;  276 16683-16689
• 23 Ajuwon KM, Spurlock ME. Adiponectin inhibits LPS-induced NF-kappaB activation and IL-6 production and increases PPARgamma2 expression in adipocytes.  Am J Physiol Regul Integr Comp Physiol. 2005;  288 R1220-R1225
• 24 Creely SJ, MacTernan PG, Kusminski CM, Fisher M, Da Silva NF, Khanolkar M, Evans M, Harte AL, Kumar S. Lipopolysaccharide activates an innate immune system response in human adipose tissue in obesity and type 2 diabetes.  Am J Physiol Endocrinol Metab. 2007;  292 E740-E747
• 25 Frost RA, Nystrom GJ, Lang CH. Lipopolysaccharide regulates proinflammatory cytokine expression in mouse myoblasts and skeletal muscle.  Am J Physiol Regul Integr Comp Physiol. 2002;  283 R698-R709
• 26 Poggi M, Bastelica D, Gual P, Iglesias MA, Gremeaux T, Knauf C, Peirett C, Verdier M, Juhan-Vague I, Tant JF, Burcelin R, Alessi MC. C3H/HeJ mice carrying a toll-like receptor 4 mutation are protected against the development of insulin resistance in white adipose tissue in response to a high-fat diet.  Diabetologia. 2007;  50 1267-1276
• 27 Davis JE, Gabler NK, Walker-Daniels J, Spurlock ME. Tlr-4 deficiency selectively protects against obesity induced by diets high in saturated fat.  Obesity (Silver Spring). 2008;  16 1248-1255
• 28 Mohammad MK, Morran M, Slotterbeck B, Leaman DW, Sun Y, Grafenstein H, Hong SC, McInerney MF. Dysregulated Toll-like receptor expression and signaling in bone marrow-derived macrophages at the onset of diabetes in the non-obese diabetic mouse.  Int Immunol. 2006;  18 1101-1113
• 29 Murakami K, Bujo H, Unoki H, Saito Y. High fat intake induces a population of adipocytes to co-express TLR2 and TNFalpha in mice with insulin resistance.  Biochem Biophys Res Commun. 2007;  354 727-734
• 30 Senn JJ. Toll-like receptor-2 is essential for the development of palmitate-induced insulin resistance in myotubes.  J Biol Chem. 2006;  281 26865-26875
• 31 Adhikary G, Sun Y, Pearlman E. C-Jun NH₂ terminal kinase (JNK) is an essential mediator of Toll-like receptor 2-induced corneal inflammation.  J Leukoc Biol. 2008;  83 991-997
• 32 Lee JY, Zhao L, Youn HS, Weatherill AR, Tapping R, Feng L, Lee WH, Fitzgerald KA, Hwang DH. Saturated fatty acid activates but polyunsaturated fatty acid inhibits Toll-like receptor 2 dimerized with Toll-like receptor 6 or 1.  J Biol Chem. 2004;  279 16971-16979
• 33 Shishido T, Nozaki N, Takahashi H, Arimoto T, Niizeki T, Koyama Y, Abe J, Takeishi Y, Kubota I. Central role of endogenous Toll-like receptor-2 activation in regulating inflammation, reactive oxygen species production, and subsequent neointimal formation after vascular injury.  Biochem Biophys Res Commun. 2006;  345 1446-1453
• 34 Ajuwon KM, Jacobi SK, Kuske JL, Spurlock ME. Interleukin-6 and interleukin-15 are selectively regulated by lipopolysaccharide and interferon-gamma in primary pig adipocytes.  Am J Physiol Regul Integr Comp Physiol. 2004;  286 R547-R553
• 35 Nguyen MT, Satoh H, Favelyukis S, Babendure JL, Imamura T, Sbodio JI, Zalevsky J, Dahiyat BI, Chi NW, Olefsky JM. JNK and tumor necrosis factor-alpha mediate free fatty acid-induced insulin resistance in 3T3-L1 adipocytes.  J Biol Chem. 2005;  280 35361-35371
• 36 Nozaki M, Fukuhara A, Segawa K, Okuno Y, Abe M, Hosogai N, Matsuda M, Komuro R, Shimomura I. Nitric oxide dysregulates adipocytokine expression in 3T3-L1 adipocytes.  Biochem Biophys Res Commun. 2007;  364 33-39
• 37 Lang CH, Dobrescu C. Gram-negative infection increases noninsulin-mediated glucose disposal.  Endocrinology. 1991;  128 645-653
• 38 Nguyen MT, Favelyukis S, Nguyen AK, Reichart D, Scott PA, Jenn A, Liu-Bryan R, Glass CK, Neels JG, Olefsky JM. A subpopulation of macrophages infiltrates hypertrophic adipose tissue and is activated by free fatty acids via Toll-like receptors 2 and 4 and JNK-dependent pathways.  J Biol Chem. 2007;  282 35279-35292
• 39 Lin Y, Lee H, Berg AH, Lisanti MP, Shapiro L, Scherer PE. The lipopolysaccharide-activated toll-like receptor (TLR)-4 induces synthesis of the closely related receptor TLR-2 in adipocytes.  J Biol Chem. 2000;  275 24255-24263
• 40 Xu H, Barnes GT, Yang Q, Tan G, Yang D, Chou CJ, Sole J, Nichols A, Ross JS, Tartaglia LA, Chen H. Chronic inflammation in fat plays a crucial role in the development of obesity-related insulin resistance.  J Clin Invest. 2003;  112 1821-1830
• 41 Lee JG, Lee SH, Park DW, Lee SH, Yoon HS, Chin BR, Kim JH, Kim JR, Baek SH. Toll-like receptor 9-stimulated monocyte chemoattractant protein-1 is mediated via JNK-cytosolic phospholipase A2-ROS signaling.  Cell Signal. 2008;  20 105-111
• 42 Kaneto H, Matsuoka TA, Nakatani Y, Kawamori D, Matsuhisa M, Yamasaki Y. Involvement of c-Jun N-terminal kinase in oxidative stress-mediated suppression of insulin gene expression.  J Biol Chem. 2002;  277 30010-30018
• 43 Bennett BL, Sasaki DT, Murray BW, O’Leary EC, Sakata ST, Xu W, Leisten JC, Motiwala A, Pierce S, Satoh Y, Bhagwat SS, Manning AM, Anderson DW. SP600125, an anthrapyrazolone inhibitor of Jun N-terminal kinase.  Proc Natl Acad Sci USA. 2001;  98 13681-13686
• 44 Lin Y, Berg AH, Iyengar P, Lam TK, Giacca A, Combs TP, Rajala MW, Du X, Rollman B, Li W, Hawkins M, Barzilai N, Rhodes CJ, Fantus IG, Brownlee M, Scherer PE. The hyperglycemia-induced inflammatory response in adipocytes: the role of reactive oxygen species.  J Biol Chem. 2005;  280 4617-4626
• 45 Takeda K, Akira S. TLR signaling pathways.  Semin Immunol. 2004;  16 3-9
• 46 Kawai T, Akira S. TLR signaling.  Semin Immunol. 2007;  19 24-32

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