Abstract
Purpose
Dabigatran etexilate (DE) constitutes a novel, direct thrombin inhibitor. Regarding the association of thrombin with atherogenesis, we assessed the effects of DE on the development and stability of atherosclerotic lesions in apolipoprotein-E deficient (ApoE−/−) mice.
Materials-methods
Fifty male ApoE−/− mice were randomized to receive western-type diet either supplemented with DE 7.5 mg DE/g chow) (DE-group, n = 25) or matching placebo as control (CO-group, n = 25) for 12 weeks. After this period, all mice underwent carotid artery injury with ferric chloride and the time to thrombotic total occlusion (TTO) was measured. Then, mice were euthanatized and each aortic arch was analyzed for the mean plaque area, the content of macrophages, elastin, collagen, nuclear factor kappaB (NFκB), vascular cell adhesion molecule-1 (VCAM-1), matrix metalloproteinase-9 (MMP-9) and its inhibitor (TIMP-1).
Results
DE-group showed significantly longer TTO compared to CO-group (8.9 ± 2.3 min vs 3.5 ± 1.1 min, p < 0.001) and the mean plaque area was smaller in DE-group than CO-group (441.00 ± 160.01 × 103 μm2 vs 132.12 ± 32.17 × 103 μm2, p < 0.001). Atherosclerotic lesions derived from DE-treated mice showed increased collagen (p = 0.043) and elastin (p = 0.031) content, thicker fibrous caps (p < 0.001) and reduced number of internal elastic lamina ruptures per mm of arterial girth (p < 0.001) when compared to CO-group. Notably, DE treatment seemed to promote plaque stability possibly by reducing concentrations of NFκB, VCAM-1, macrophages and MMP-9 and increasing TIMP-1 within atherosclerotic lesions (p < 0.05).
Conclusions
DE attenuates arterial thrombosis, reduces lesion size and may promote plaque stability in ApoE−/− mice. The plaque-stabilizing effects of chronic thrombin inhibition might be the result of the favorable modification of inflammatory mechanisms.
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References
Ambrose JA, Srikanth S. Vulnerable plaques and patients: improving prediction of future coronary events. Am J Med. 2010;123:10–6.
Kadoglou NP, Kostomitsopoulos N, Kapelouzou A, Moustardas P, Katsimpoulas M, Giagini A, et al. Effects of exercise training on the severity and composition of atherosclerotic plaque in apoE-deficient mice. J Vasc Res. 2011;48:347–56.
Jennings LK. Mechanisms of platelet activation: need for new strategies to protect against platelet-mediated atherothrombosis. Thromb Haemost. 2009;102:248–57.
Hamilton JR, Cocks TM. Heterogeneous mechanisms of endothelium-dependent relaxation for thrombin and peptide activators of protease-activated receptor-1 in porcine isolated coronary artery. Br J Pharmacol. 2000;130:181–8.
Hirano K. The roles of proteinase-activated receptors in the vascular physiology and pathophysiology. Arterioscler Thromb Vasc Biol. 2007;27:27–36.
Smyth SS, McEver RP, Weyrich AS, Morrell CN, Hoffman MR, Arepally GM, et al. Platelet colloquium participants. Platelet functions beyond hemostasis. J Thromb Haemost. 2009;7:1759–66.
Levi M, van der Poll T. Two-way interactions between inflammation and coagulation. Trends Cardiovasc Med. 2005;15:254–9.
Tracy R. Thrombin, inflammation, and cardiovascular disease. Chest. 2003;124:49S–57.
Wienen W, Stassen JM, Priepke H, Ries UJ, Hauel N. In-vitro profile and ex-vivo anticoagulant activity of the direct thrombin inhibitor dabigatran and its orally active prodrug, dabigatran etexilate. Thromb Haemost. 2007;98:155–62.
Harenberg J, Marx S, Wehling M, Krejczy M. New anticoagulants - promising and failed developments. Br J Pharmacol. 2012;165:363–72.
Hankey GJ, Eikelboom JW. Dabigatran etexilate: a new oral thrombin inhibitor. Circulation. 2011;123:1436–50.
Fuster JJ, Castillo AI, Zaragoza C, Ibáñez B, Andrés V. Animal models of atherosclerosis. Prog Mol Biol Transl Sci. 2012;105:1–23.
Vicente CP, He L, Tollefsen DM. Accelerated atherogenesis and neointima formation in heparin cofactor II deficient mice. Blood. 2007;110:4261–7.
Rotzius P, Thams S, Soehnlein O, Kenne E, Tseng CN, Bjorkstrom NK, et al. Distinct infiltration of neutrophils in lesion shoulders in apoe−/−mice. Am J Pathol. 2010;177:493–500.
Kadoglou NP, Liapis CD. Matrix metalloproteinases: contribution to pathogenesis, diagnosis, surveillance and treatment of abdominal aortic aneurysms. Curr Med Res Opin. 2004;20:419–32.
Pynn M, Schäfer K, Konstantinides S, Halle M. Exercise training reduces neointimal growth and stabilizes vascular lesions developing after injury in apolipoprotein e-deficient mice. Circulation. 2004;109:386–92.
Tracqui P, Broisat A, Toczek J, Mesnier N, Ohayon J, Riou L. Mapping elasticity moduli of atherosclerotic plaque in situ via atomic force microscopy. J Struct Biol. 2011;174:115–23.
Bea F, Kreuzer J, Preusch M, Schaab S, Isermann B, Rosenfeld ME, et al. Melagatran reduces advanced atherosclerotic lesion size and may promote plaque stability in apolipoprotein E-deficient mice. Arterioscler Thromb Vasc Biol. 2006;26:2787–92.
Testa L, Bhindi R, Agostoni P, Abbate A, Zoccai GG, van Gaal WJ. The direct thrombin inhibitor ximelagatran/melagatran: a systematic review on clinical applications and an evidence based assessment of risk benefit profile. Expert Opin Drug Saf. 2007;6:397–406.
Ylä-Herttuala S, Bentzon JF, Daemen M, Falk E, Garcia-Garcia HM, Herrmann J, et al. Stabilisation of atherosclerotic plaques. Position paper of the European Society of Cardiology Working Group on atherosclerosis and vascular biology. Thromb Haemost. 2011;106:1–19.
Clarke M, Bennett M. The emerging role of vascular smooth muscle cell apoptosis in atherosclerosis and plaque stability. Am J Nephrol. 2006;26:531–5.
Olson ES, Whitney MA, Friedman B, Aguilera TA, Crisp JL, Baik FM, et al. In vivo fluorescence imaging of atherosclerotic plaques with activatable cell-penetrating peptides targeting thrombin activity. Integr Biol (Camb). 2012;4:595–605.
Pou J, Rebollo A, Piera L, Merlos M, Roglans N, Laguna JC, et al. Tissue factor pathway inhibitor 2 is induced by thrombin in human macrophages. Biochim Biophys Acta. 2011;1813:1254–60.
DeGraba TJ. Immunogenetic susceptibility of atherosclerotic stroke: implications on current and future treatment of vascular inflammation. Stroke. 2004;35:2712–9.
Newby AC. Metalloproteinases and vulnerable atherosclerotic plaques. Trends Cardiovasc Med. 2007;17:253–8.
Feistritzer C, Wiedermann CJ. Effects of anticoagulant strategies on activation of inflammation and coagulation. Expert Opin Biol Ther. 2007;7:855–70.
Kaur J, Woodman RC, Kubes P. P38 MAPK: critical molecule in thrombin-induced NF-kappa B-dependent leukocyte recruitment. Am J Physiol Heart Circ Physiol. 2003;284:H1095–103.
Jennewein C, Paulus P, Zacharowski K. Linking inflammation and coagulation: novel drug targets to treat organ ischemia. Curr Opin Anaesthesiol. 2011;24:375–80.
Graebe M, Pedersen SF, Borgwardt L, Højgaard L, Sillesen H, Kjaer A. Molecular pathology in vulnerable carotid plaques: correlation with [18]-fluorodeoxyglucosepositron emission tomography (FDG-PET). Eur J Vasc Endovasc Surg. 2009;37:714–21.
de Nooijer R, Verkleij CJ, von der Thüsen JH, Jukema JW, van der Wall EE, van Berkel TJ, et al. Lesional overexpression of matrix metalloproteinase-9 promotes intraplaque hemorrhage in advanced lesions but not at earlier stages of atherogenesis. Arterioscler Thromb Vasc Biol. 2006;26:340–6.
Kadoglou NP, Daskalopoulou SS, Perrea D, Liapis CD. Matrix metalloproteinases and diabetic vascular complications. Angiology. 2005;56:173–89.
Holven KB, Halvorsen B, Bjerkeli V, Damås JK, Retterstøl K, Mørkrid L, et al. Impaired inhibitory effect of interleukin-10 on the balance between matrix metalloproteinase-9 and its inhibitor in mononuclear cells from hyperhomocysteinemic subjects. Stroke. 2006;37:1731–6.
Skjøt-Arkil H, Barascuk N, Register T, Karsdal MA. Macrophagemediatedproteolytic remodeling of the extracellular matrix in atherosclerosis results inneoepitopes: a potential new class of biochemical markers. Assay Drug Dev Technol. 2010;8:542–52.
Acknowledgments
This study was financed in part by Boehringer Ingelheim. Nikolaos P.E. Kadoglou was awarded a grant by the Greek State Scholarship’s Foundation.
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Kadoglou, N.P.E., Moustardas, P., Katsimpoulas, M. et al. The Beneficial Effects of a Direct Thrombin Inhibitor, Dabigatran Etexilate, on the Development and Stability of Atherosclerotic Lesions in Apolipoprotein E-deficient Mice. Cardiovasc Drugs Ther 26, 367–374 (2012). https://doi.org/10.1007/s10557-012-6411-3
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DOI: https://doi.org/10.1007/s10557-012-6411-3