Platelets as a novel source of Gremlin-1: Implications for thromboinflammation

Summary

Platelets mediating haemostasis-thrombosis are central players in coronary artery disease (CAD). We characterised platelets as a novel source of Gremlin-1. Platelets express Gremlin-1 like inflammatory and endothelial cells. Gremlin-1 co-localised with P-selectin containing randomly distributed α–granules under resting state, which were peripheralised following platelet activation or adhesion over fibrinogen-coated surface. Gremlin-1 release upon activation with ADP, CRP, and TRAP was detected as enhanced surface expression; also in activated platelet supernatant as detected by Western Blot following CRP activation and by ELISA upon activation with ADP, CRP, PAR-1, and PAR4 agonist. Recombinant (rh)Gremlin-1 synergistically enhanced CRP-triggered intracellular calcium mobilisation, ADP-TRAP induced platelet activation, aggregation, and thrombin-activation triggered apoptosis; also thrombus formation ex vivo. Intracellular localisation of macrophage migration inhibitory factor (MIF) and Gremlin-1 a high-affinity binding partner and functional antagonist of MIF were found in intracoronary thrombus sections from acute coronary syndrome (ACS) patients and showed moderate overlap in α-granules of platelets. Intra-platelet Gremlin-1 levels were significantly decreased in ACS patients as compared to stable CAD (n=235). rhGremlin-1 also counteracted the anti-apoptotic and anti-thrombotic effects of rhMIF on platelets. Platelet-derived-Gremlin-1 prompted monocyte migration, facilitated adhesion under static and dynamic arterial flow conditions to collagen-adherent activated platelets; supported monocyte survival against BH-3-mimetic–induced apoptosis and macrophage differentiation in monocyte-platelet co-culture system, which were counteracted upon Gremlin-1 neutralisation. Thus platelet derived Gremlin-1 might contribute to the elevated circulating levels of Gremlin-1 in ACS and serve as a thrombo-inflammatory mediator in cardiovascular pathophysiologies.

Keywords

Gremlin-1 - platelets - thrombus - monocytes - acute coronary syndrome

• References

• 1 Gawaz M. et al. Platelets in inflammation and atherogenesis. J Clin Invest 2005; 115: 3378-3384.
• 2 May AE. et al. Platelets: inflammatory firebugs of vascular walls. Arterioscler Thromb Vasc Biol 2008; 28: s5-10.
• 3 Chatterjee M. et al. Distinct platelet packaging, release, and surface expression of proangiogenic and antiangiogenic factors on different platelet stimuli. Blood 2011; 117: 3907-3911.
• 4 Chatterjee M, Gawaz M. Platelet-derived CXCL12 (SDF-1alpha): basic mechanisms and clinical implications. J Thromb Haemost 2013; 11: 1954-1967.
• 5 Muller I. et al. Gremlin-1 is an inhibitor of macrophage migration inhibitory factor and attenuates atherosclerotic plaque growth in ApoE-/- Mice. J Biol Chem 2013; 288: 31635-31645.
• 6 Muller II. et al. Gremlin-1 inhibits macrophage migration inhibitory factor-dependent monocyte function and survival. Int J Cardiol 2014; 176: 923-929.
• 7 Beck S. et al. Gremlin-1 C-Terminus Regulates Function of Macrophage Migration Inhibitory Factor (MIF). Cell Physiol Biochem 2016; 38: 801-808.
• 8 Mueller I. et al. Impact of counterbalance between macrophage migration inhibitory factor and its inhibitor Gremlin-1 in patients with coronary artery disease. Atherosclerosis 2014; 237: 426-432.
• 9 Müller KA. et al. High Plasma Levels of Gremlin-1 and Macrophage Migration Inhibitory Factor, but Not Their Ratio, Indicate an Increased Risk for Acute Coronary Syndrome in Patients With Type 2 Diabetes Mellitus. Clin Cardiol 2016; 39: 201-206.
• 10 Chatterjee M. et al. Macrophage migration inhibitory factor limits activation-induced apoptosis of platelets via CXCR7-dependent Akt signaling. Circ Res 2014; 115: 939-949.
• 11 Strüßmann T. et al. Platelets are a previously unrecognised source of MIF. Thromb Haemost 2013; 110: 1004-1113.
• 12 Chatterjee M. et al. SDF-1α induces differential trafficking of CXCR4-CXCR7 involving cyclophilin A, CXCR7 ubiquitination and promotes platelet survival. FASEB J 2014; 08: 2864-2678.
• 13 Liu G. et al. CD44 sensitivity of platelet activation, membrane scrambling and adhesion under high arterial shear rates. Thromb Haemost 2016; 115: 99-108.
• 14 Geisler T. et al. High Platelet Reactivity in Patients with Acute Coronary Syndromes Undergoing Percutaneous Coronary Intervention: Randomised Controlled Trial Comparing Prasugrel and Clopidogrel. PLoS One 2015; 10: e0135037.
• 15 Chatterjee M. et al. Platelet-derived CXCL12 regulates monocyte function, survival, differentiation into macrophages and foam cells through differential involvement of CXCR4-CXCR7. Cell Death Dis 2015; 06: e1989.
• 16 Topol LZ. et al. Biosynthesis, post-translation modification, and functional characterisation of Drm/Gremlin. J Biol Chem 2000; 275: 8785-8793.
• 17 Michos O. et al. Reduction of BMP4 activity by gremlin 1 enables ureteric bud outgrowth and GDNF/WNT11 feedback signalling during kidney branching morphogenesis. Development 2007; 134: 2397-2405.
• 18 Shi W. et al. Gremlin negatively modulates BMP-4 induction of embryonic mouse lung branching morphogenesis. Am J Physiol Lung Cell Mol Physiol 2001; 280: L1030-L1039.
• 19 Chen B. et al. Cutting edge: bone morphogenetic protein antagonists Drm/Gremlin and Dan interact with Slits and act as negative regulators of monocyte chemotaxis. J Immunol 2004; 173: 5914-5917.
• 20 Chiodelli P. et al. Heparan sulfate proteoglycans mediate the angiogenic activity of the vascular endothelial growth factor receptor-2 agonist gremlin. Arterioscler Thromb Vasc Biol 2011; 31: e116-e127.
• 21 Mitola S. et al. Gremlin is a novel agonist of the major proangiogenic receptor VEGFR2. Blood 2010; 116: 3677-3680.
• 22 Chang K. et al. Bone morphogenic protein antagonists are coexpressed with bone morphogenic protein 4 in endothelial cells exposed to unstable flow in vitro in mouse aortas and in human coronary arteries: role of bone morphogenic protein antagonists in inflammation and atherosclerosis. Circulation 2007; 116: 1258-1266.
• 23 Maciel TT. et al. Gremlin promotes vascular smooth muscle cell proliferation and migration. J Mol Cell Cardiol 2008; 44: 370-379.
• 24 Mueller KA. et al. Gremlin-1 identifies fibrosis and predicts adverse outcome in patients with heart failure undergoing endomyocardial biopsy. J Card Fail 2013; 19: 678-684.
• 25 Karagiannis GS. et al. Bone morphogenetic protein antagonist gremlin-1 regulates colon cancer progression. Biol Chem 2015; 396: 163-183.
• 26 Namkoong H. et al. The bone morphogenetic protein antagonist gremlin 1 is overexpressed in human cancers and interacts with YWHAH protein. BMC Cancer 2006; 06: 74.
• 27 Sneddon JB. et al. Bone morphogenetic protein antagonist gremlin 1 is widely expressed by cancer-associated stromal cells and can promote tumor cell proliferation. Proc Natl Acad Sci USA 2006; 103: 14842-14847.
• 28 Topol LZ. et al. Identification of drm, a novel gene whose expression is suppressed in transformed cells and which can inhibit growth of normal but not transformed cells in culture. Mol Cell Biol 1997; 17: 4801-4810.
• 29 Kim M. et al. Gremlin-1 induces BMP-independent tumor cell proliferation, migration, and invasion. PLoS One 2012; 07: e35100.
• 30 Cahill E. et al. Gremlin plays a key role in the pathogenesis of pulmonary hypertension. Circulation 2012; 125: 920-930.
• 31 Massberg S. et al. A crucial role of glycoprotein VI for platelet recruitment to the injured arterial wall in vivo. J Exp Med 2003; 197: 41-49.
• 32 Ziegler M. et al. The bispecific SDF1-GPVI fusion protein preserves myocardial function after transient ischemia in mice. Circulation 2012; 125: 685-696.