CD40L induces inflammation and adipogenesis in adipose cells – a potential link between metabolic and cardiovascular disease

Summary

CD40L figures prominently in atherogenesis. Recent data demonstrate elevated levels of sCD40L in the serum of patients with the metabolic syndrome (MS). This study investigated the role of CD40L in pro-inflammatory gene expression and cellular differentiation in adipose tissue to obtain insight into mechanisms linking the MS with atherosclerosis. Human adipocytes and preadipocytes expressed CD40 but not CD40L. Stimulation with recombinant CD40L or membranes over-expressing CD40L induced a time- and dose-dependent expression of IL-6, MCP-1, IL-8, and PAI-1. Supernatants of CD40L-stimulated adipose cells activated endothelial cells, suggesting a systemic functional relevance of our findings. Neutralising antibodies against CD40L attenuated these effects substantially. Signalling studies revealed the involvement of mitogen-activated protein kinases and NFκB. Furthermore, stimulation with CD40L resulted in enhanced activation of C/EBPα and PPARγ and promoted adipogenesis of preadipose cells in the presence and absence of standard adipogenic conditions. Finally, patients suffering from the metabolic syndrome with high levels of sCD40L also displayed high levels of IL-6, in line with the concept that CD40L may induce the expression of inflammatory cytokines in vivo in this population. Our data reveal potent metabolic functions of CD40L aside from its known pivotal pro-inflammatory role within plaques. Our data suggest that CD40L may mediate risk at the interface of metabolic and atherothrombotic disease.

Keywords

CD40L - adipocytes - preadipocytes - inflammation - metabolic syndrome

^* A.M. and D.W. contributed equally to this work. N.V. and A.Z. share senior authorship.

• References

• 1 Grewal IS, Flavell RA. CD40 and CD154 in cell-mediated immunity. Annu Rev Immunol 1998; 16: 111-135.
• 2 Libby P. Inflammation in atherosclerosis. Nature 2002; 420: 868-874.
• 3 Schonbeck U, Libby P. The CD40/CD154 receptor/ligand dyad. Cell Mol Life Sci 2001; 58: 4-43.
• 4 Mach F, Schonbeck U, Sukhova GK. et al. Functional CD40 ligand is expressed on human vascular endothelial cells, smooth muscle cells, and macrophages: implications for CD40-CD40 ligand signaling in atherosclerosis. Proc Natl Acad Sci USA 1997; 94: 1931-1936.
• 5 Heeschen C, Dimmeler S, Hamm CW. et al. Soluble CD40 ligand in acute coronary syndromes. N Engl J Med 2003; 348: 1104-1111.
• 6 Schonbeck U, Varo N, Libby P. et al. Soluble CD40L and cardiovascular risk in women. Circulation 2001; 104: 2266-2268.
• 7 Varo N, de Lemos JA, Libby P. et al. Soluble CD40L: risk prediction after acute coronary syndromes. Circulation 2003; 108: 1049-1052.
• 8 Cipollone F, Ferri C, Desideri G. et al. Preprocedural level of soluble CD40L is predictive of enhanced inflammatory response and restenosis after coronary angioplasty. Circulation 2003; 108: 2776-2782.
• 9 Cipollone F, Mezzetti A, Porreca E. et al. Association between enhanced soluble CD40L and prothrombotic state in hypercholesterolemia: effects of statin therapy. Circulation 2002; 106: 399-402.
• 10 Angelico F, Alessandri C, Ferro D. et al. Enhanced soluble CD40L in patients with the metabolic syndrome: Relationship with in vivo thrombin generation. Diabetologia 2006; 49: 1169-1174.
• 11 Lee WL, Lee WJ, Chen YT. et al. The presence of metabolic syndrome is independently associated with elevated serum CD40 ligand and disease severity in patients with symptomatic coronary artery disease. Metabolism 2006; 55: 1029-1034.
• 12 Varo N, Vicent D, Libby P. et al. Elevated plasma levels of the atherogenic mediator soluble CD40 ligand in diabetic patients: a novel target of thiazolidinediones. Circulation 2003; 107: 2664-2669.
• 13 Basili S, Pacini G, Guagnano MT. et al. Insulin resistance as a determinant of platelet activation in obese women. J Am Coll Cardiol 2006; 48: 2531-2538.
• 14 Calle EE, Kaaks R. Overweight, obesity and cancer: epidemiological evidence and proposed mechanisms. Nat Rev Cancer 2004; 04: 579-591.
• 15 Wellen KE, Hotamisligil GS. Inflammation, stress, and diabetes. J Clin Invest 2005; 115: 1111-1119.
• 16 Katagiri H, Yamada T, Oka Y. Adiposity and cardiovascular disorders: disturbance of the regulatory system consisting of humoral and neuronal signals. Circ Res 2007; 101: 27-39.
• 17 Tilg H, Moschen AR. Adipocytokines: mediators linking adipose tissue, inflammation and immunity. Nat Rev Immunol 2006; 06: 772-783.
• 18 Hotamisligil GS, Shargill NS, Spiegelman BM. Adipose expression of tumor necrosis factor-alpha: direct role in obesity-linked insulin resistance. Science 1993; 259: 87-91.
• 19 Shimomura I, Funahashi T, Takahashi M. et al. Enhanced expression of PAI-1 in visceral fat: possible contributor to vascular disease in obesity. Nat Med 1996; 02: 800-803.
• 20 Gustafson B, Hammarstedt A, Andersson CX. et al. Inflamed adipose tissue: a culprit underlying the metabolic syndrome and atherosclerosis. Arterioscler Thromb Vasc Biol 2007; 27: 2276-2283.
• 21 Sharma AM, Staels B. Review: Peroxisome proliferator-activated receptor gamma and adipose tissue--understanding obesity-related changes in regulation of lipid and glucose metabolism. J Clin Endocrinol Metab 2007; 92: 386-395.
• 22 Weisberg SP, McCann D, Desai M. et al. Obesity is associated with macrophage accumulation in adipose tissue. J Clin Invest 2003; 112: 1796-1808.
• 23 Zirlik A, Leugers A, Lohrmann J. et al. Direct attenuation of plasminogen activator inhibitor type-1 expression in human adipose tissue by thiazolidinediones. Thromb Haemost 2004; 91: 674-682.
• 24 Joost HG, Weber TM. The regulation of glucose transport in insulin-sensitive cells. Diabetologia 1989; 32: 831-838.
• 25 Zirlik A, Bavendiek U, Libby P. et al. TRAF-1, –2, –3, –5, and –6 are induced in atherosclerotic plaques and differentially mediate proinflammatory functions of CD40L in endothelial cells. Arterioscler Thromb Vasc Biol 2007; 27: 1101-1107.
• 26 Isoda K, Young JL, Zirlik A. et al. Metformin inhibits proinflammatory responses and nuclear factor-kappaB in human vascular wall cells. Arterioscler Thromb Vasc Biol 2006; 26: 611-617.
• 27 Zirlik A, Ernst S, Leugers A. et al. Inhibition by fibrates of plasminogen activator inhibitor type-1 expression in human adipocytes and preadipocytes. Thromb Haemost 2009; 101: 1060-1069.
• 28 Livak KJ, Schmittgen TD. Analysis of relative gene expression data using real-time quantitative PCR and the 2(-Delta Delta C(T)) Method. Methods 2001; 25: 402-408.
• 29 Bost F, Aouadi M, Caron L. et al. The role of MAPKs in adipocyte differentiation and obesity. Biochimie 2005; 87: 51-56.
• 30 Cai D, Yuan M, Frantz DF. et al. Local and systemic insulin resistance resulting from hepatic activation of IKK-beta and NF-kappaB. Nat Med 2005; 11: 183-190.
• 31 Yuan M, Konstantopoulos N, Lee J. et al. Reversal of obesity- and diet-induced insulin resistance with salicylates or targeted disruption of Ikkbeta. Science (New York) 2001; 29: 1673-1677.
• 32 Farmer SR. Transcriptional control of adipocyte formation. Cell Metab 2006; 04: 263-273.
• 33 Pou KM, Massaro JM, Hoffmann U. et al. Visceral and subcutaneous adipose tissue volumes are cross-sectionally related to markers of inflammation and oxidative stress: the Framingham Heart Study. Circulation 2007; 116: 1234-1241.
• 34 Bavendiek U, Zirlik A, LaClair S. et al. Atherogenesis in mice does not require CD40 ligand from bone marrow-derived cells. Arterioscler Thromb Vasc Biol 2005; 25: 1244-1249.
• 35 Lutgens E, Gorelik L, Daemen MJ. et al. Requirement for CD154 in the progression of atherosclerosis. Nat Med 1999; 05: 1313-1316.
• 36 Mach F, Schonbeck U, Sukhova GK. et al. Reduction of atherosclerosis in mice by inhibition of CD40 signalling. Nature 1998; 394: 200-203.
• 37 Gokulakrishnan K, Deepa R, Mohan V. et al. Soluble P-selectin and CD40L levels in subjects with prediabetes, diabetes mellitus, and metabolic syndrome--the Chennai Urban Rural Epidemiology Study. Metabolism 2006; 55: 237-242.
• 38 Natal C, Restituto P, Colina I. et al. The pro-inflammatory mediator CD40 ligand is increased in the metabolic syndrome and modulated by adiponectin. J Clin Endocrinol Metab 2008; 93: 2319-2327.
• 39 Schernthaner GH, Kopp HP, Krzyzanowska K. et al. Soluble CD40L in patients with morbid obesity: significant reduction after bariatric surgery. Eur J Clin Invest 2006; 36: 395-401.
• 40 Wu H, Ghosh S, Perrard XD. et al. T-cell accumulation and regulated on activation, normal T cell expressed and secreted upregulation in adipose tissue in obesity. Circulation 2007; 115: 1029-1038.
• 41 Poggi M, Jager J, Paulmyer-Lacroix O. et al. The inflammatory receptor CD40 is expressed on human adipocytes: contribution to crosstalk between lymphocytes and adipocytes. Diabetologia 2009; 52: 1152-1163.
• 42 Mason PJ, Chakrabarti S, Albers AA. et al. Plasma, serum, and platelet expression of CD40 ligand in adults with cardiovascular disease. Am J Cardiol 2005; 96: 1365-1369.
• 43 Nagasawa M, Zhu Y, Isoda T. et al. Analysis of serum soluble CD40 ligand (sCD40L) in the patients undergoing allogeneic stem cell transplantation: platelet is a major source of serum sCD40L. Eur J Haematol 2005; 74: 54-60.
• 44 Cipollone F, Chiarelli F, Davi G. et al. Enhanced soluble CD40 ligand contributes to endothelial cell dysfunction in vitro and monocyte activation in patients with diabetes mellitus: effect of improved metabolic control. Diabetologia 2005; 48: 1216-1224.
• 45 Young JL, Libby P, Schonbeck U. Cytokines in the pathogenesis of atherosclerosis. Thromb Haemost 2002; 88: 554-567.
• 46 Kanda H, Tateya S, Tamori Y. et al. MCP-1 contributes to macrophage infiltration into adipose tissue, insulin resistance, and hepatic steatosis in obesity. J Clin Invest 2006; 116: 1494-1505.
• 47 Kohler HP, Grant PJ. Plasminogen-activator inhibitor type 1 and coronary artery disease. N Engl J Med 2000; 342: 1792-1801.
• 48 Poirier P, Giles TD, Bray GA. et al. Obesity and cardiovascular disease: pathophysiology, evaluation, and effect of weight loss. Arterioscler Thromb Vasc Biol 2006; 26: 968-976.