Emerging Factors Implicated in Fibrotic Organ–Associated Thrombosis: The Case of Two Organs

Abstract

Thrombosis is at the heart of cardiovascular complications observed in specific diseases. A heightened thrombosis risk above that in general population in diseases such as myelofibrosis and chronic kidney disease implicates disease-specific mediators of thrombosis. This relative lack of information regarding the mechanisms of thrombosis in specific organ pathologies hitherto has remained limited. Evolving literature implicates some soluble factors in the blood of patients with discrete disorders, inflicting fundamental changes in the components of thrombosis. In this era of precision medicine, integrating these disease-specific factors in a comprehensive thrombotic risk assessment of patients is imperative in guiding therapeutic decisions. A complex network of mechanisms regulates each organ pathology and resultant thrombotic phenotypes. This review surveys different effectors of thrombogenicity associated with two pathologically fibrotic organs used as model systems, the bone marrow and kidney, as well as focuses attention to a common inducer of fibrosis and thrombosis, lysyl oxidase.

Keywords

thrombosis - myelofibrosis - chronic kidney disease - lysyl oxidase - fibrosis

Overview

Cardiovascular disease has protean manifestation including stroke and acute coronary syndromes (ACSs), heart failure, and venous thrombosis with pulmonary embolism (combined as venous thromboembolism [VTE]). Arterial or venous or microvascular thrombosis underlies most of these events either as a direct causal factor (stroke or ACS or VTE) or as an important contributor. While cardiovascular disease remains a number 1 cause of death in general population, its risk is increased in certain unrelated diseases such as primary myelofibrosis (PMF), chronic kidney disease (CKD), or cancer, to name a few.

PMF, which is characterized by augmented proliferation of cells of the myeloid lineage, the megakaryocytes, and a fibrotic marrow,[1] is associated with increased propensity for cardiovascular disease.[2] [3] A study of 707 patients with PMF followed up in four European institutions showed that fatal and nonfatal thromboses were documented in 51 (7.2%) patients, with a rate of 1.75% patient-years. Of patients with nonfatal cardiovascular events (47), 1% had acute myocardial infarction (MI) and 3.1% had VTE.[4] The risk of developing a fatal or nonfatal thrombotic event in PMF was found to be 2.2% patient-years. PMF has been associated with increased risk of both venous and arterial thrombosis.[5] [6] A very recent meta-analysis estimated that the overall prevalence of thrombosis in patients with myeloproliferative neoplasms (MPNs) is 20% with the prevalence of arterial thrombosis (cerebrovascular disease, transient ischemic attack, coronary artery disease, and peripheral artery disease) being 16.2% and VTE being 6.2%.[7] Another meta-analysis led to the conclusion that JAK2V617F mutation in PMF patients is associated with an increased risk of thrombosis (odds ratio: 1.76, 95% confidence interval [CI]: 0.91–3.41).[4]

As for CKD, currently approximately 10% of the adult population in the United States and worldwide suffer from this pathology. These rates are rising at an alarming proportion, and CKD patients will be 28 million in 2020 and nearly 38 million in 2030 in the United States.[8] [9] Similar to PMF, end-stage renal disease is associated with a 2.3-fold increase risk of VTE as compared with the general population,[10] and patients on dialysis have 11.9-fold and 8.4-fold increased chance of developing ACS and stroke, respectively.[11]

This substantial increase in the risk of cardiovascular events suggests a possibility of underlying disease-specific mediators. While the general mechanisms of thrombosis have been well defined and have driven the development of current antiplatelet and antithrombotic agents, the disease-specific factors that augment thrombotic risk in each pathology remain less characterized. It is important to investigate the disease-specific mediators to develop biomarkers or therapeutic targets to augment the efficiency of current antithrombotic that largely perturb normal hemostatic defense in the blood. Accordingly, the aim of this review is to focus on two organ systems as means of illustrating specific organ pathology-evoked mediators of thrombosis. More specifically, the goal is to shed light on various PMF- or CKD-associated factors that are involved in the pathophysiology of their respective diseases but also contribute to increased thrombotic risk.

From Pathological Fibrosis in Primary Myelofibrosis to Thrombosis

PMF is the least frequent among the MPNs. It can range from pre-PMF, exhibiting JAK2, CALR, MPL mutations, megakaryocyte proliferation, and atypia with grade 1 fibrosis, to overt PMF, which displays grades 2 to 3 fibrosis.[1] [12] As noted earlier, human studies suggest that JAK2V617F mutations in PMF are associated with higher rates of thrombosis, and increased platelet activation, with a greater allele burden portending the highest risk.[13] [14] Mimicking human phenotypes in mice has uncovered an interesting interplay of different components driving thrombosis in various types of MPN. For example, models using mainly polycythemia vera/PMF phenotype showed highly unstable thrombi in a ferric chloride-induced injury model of thrombosis and prolonged bleeding times, compared with matching controls.[15] In other systems, where the phenotype was more essential thrombocytosis (ET)-like, increased platelet reactivity to some agonists was found with decreased thrombosis after injury driven by an acquired von Willebrand factor (vWF) deficiency.[16]

Platelets in Primary Myelofibrosis

Platelets constitute a critical component of thrombus formation and propagation.[17] [18] Upon exposure to specific ligands, platelets undergo rapid activation that leads to platelet adhesion, aggregation, and secretion of granule content. Platelets can be activated by circulating factors, such as thrombin, adenosine diphosphate (ADP), and epinephrine, which target specific receptors.[19] [20] Platelets are also activated upon interaction with subendothelial collagen and fibronectin exposed in an injured vasculature.[21] [22] Platelet binding to the vessel wall is mediated through the collagen receptors, integrins α2β1 or glycoprotein (GP)VI,[23] or the fibronectin receptors αvβ3 or αvβ1, or indirectly through vWF via platelet GPIb/IX/V complex.[24] [25] Type IV collagen is the only matrix protein that supports both platelet adhesion and complete activation.[23] Epidemiologic data revealed a potentially important role for α₂β₁ in thrombotic events,[26] [27] [28] [29] [30] [31] and higher expression of GPVI is associated with poorer outcome in ACS.[32] Although some of these receptors might play a role in heightened platelet activation documented in PMF patients,[33] antiplatelet therapy is currently not part of a routine regimen of treatment. While a study showed that the effectiveness of aspirin therapy in PMF patients depends on platelet count,[34] randomized data with regard to antiplatelet therapy remains undocumented.

Contribution of Vascular and Immune Cells to Thrombogenicity in PMF

PMF is also associated with changes in cells that are known to contribute to a thrombotic phenotype, such as vascular or immune cells. The contribution of endothelial cell dysfunction in MPN was established using mice carrying specific JAK2V617F knock-in mutations. These mice have defective platelet responses to ristocetin, with unaltered platelet counts, suggesting a role for JAK2V617F-mediated vWF processing.[16] This implicates that endothelial dysfunction, with decreased vWF secretion and processing, is a contributing factor to the JAK2V617F phenotype. Furthermore, endothelial cells carrying the JAK2V617F mutation display prothrombotic features,[35] and vascular endothelial cell expression of JAK2V617F promotes thrombosis owed by upregulated P-selectin.[36] Patients with JAK2V617F-mutated MPN were shown to have increased megakaryocyte heparanase expression, possibly through an upregulated erythropoietin receptor.[37] Heparanase is an upregulator of tissue factor (TF) in endothelial cells through a p38-mediated phosphorylation and subsequent increase in procoagulant activity. This may contribute to hypercoagulability in PMF.[37] [38] Recently, granulocytes in JAK2V617F PMF mice have also been shown to contribute to the increased thrombogenic phenotype in mice that underwent inferior vena cava partial ligation.[39] Anti-α4-integrin (anti-VLA-4) and anti–β2 integrin antibodies targeting granulocytes interfered with thrombosis through inhibition of leukocyte–endothelial interactions. Additionally, abnormal trafficking of JAK2V617F-positive granulocytes to the white pulp and marginal zone of the spleen could be prevented by the use of anti–β2 antibodies.[39] Alterations in other soluble factors in blood and in the vessel wall matrix in PMF could augment their thrombogenicity. PMF is associated with elevation of interleukin (IL)-6 and C-reactive protein (CRP) which are known to contribute to increased risk for thrombotic events. Disease progression correlates with higher CRP levels and higher JAK2V617F levels.[40] Finally, hypermethylation of MAC1, a receptor on leukocytes primarily involved in phagocytosis, was found to be an independent risk factor for thrombotic complications in patients with MPN.[41] Increased expression of MAC-1 on neutrophils allows interactions with platelets to assist in the assembly of coagulation proteins. Thus, several factors in PMF contribute to platelet or vascular activation, the level and significance of which would require personalized assessment.

The Role of a Fibrosis Regulator, Lysyl Oxidase

Though the earlier-described cell types have been implicated in promoting a thrombotic phenotype in PMF, lysyl oxidase (LOX) is an enzyme secreted from megakaryocytes in PMF, with ability to control both fibrosis and thrombosis. LOX catalyzes the final reaction required for biosynthetic collagen and elastin cross-linking and maturation to result in functional connective tissues. LOX is elevated in megakaryocytes of JAK2V617F PMF mice and human samples, and may contribute to the thrombophilia in these patients.[42] [43] LOX is selectively expressed in 2N and 4N megakaryocytes. LOX expression was approximately 1.5-fold higher in PMF megakaryocytes. Interestingly, LOX expression was approximately 20-fold higher in platelets when compared with healthy subjects.[44] In addition to the increased blood levels, celltype specific increase in LOX also contributes to the thrombosis. Human PMF platelets were also found to have elevated LOX and increased α2β1-mediated platelet adhesion to collagen.[42] Increased LOX in platelets led to augmented platelet aggregation in response to collagen and quicker time to thrombosis in a carotid artery injury model of thrombosis.[45] Using LOX pharmacological inhibitor, this study concluded that the collagen receptor α2β1 is regulated by LOX. Transgenic upregulation of LOX in WT mice resulted in increased interaction between monomeric collagen and the α2β1 integrin.[45] On the other hand, fibrillar collagen did not enhance adhesion in both transgenic-upregulated LOX-containing platelets and PMF platelets.

From Chronic Kidney Disease and Fibrosis to Thrombosis

As noted earlier, CKD is a strong and independent risk factor for cardiovascular disease.[46] CKD is marked by loss of function of glomeruli, and by gradual development of fibrotic tissue.[47] Fibrosis is a common final mechanism of CKD irrespective of inciting pathology initiating CKD. Decreased renal function is a risk factor for death after MI and percutaneous coronary intervention (PCI).[48]

The Role of Endothelial Cells and Platelets

Several components of thrombosis are affected in CKD. Patients with CKD have increased platelet aggregation with ADP at baseline than non-CKD patients.[49] [50] The endothelium has also been recognized as a significant contributor to the prothrombotic state in CKD. Endothelial vWF and plasminogen activator inhibitor-1 secretion in patients with CKD is increased. Next to this, several prothrombotic coagulation factors (VII, VIII, IX–XII) show increased activity in CKD, while protein C level is reduced. Further, platelets become increasingly responsive to agonists. Second, the endothelium loses its ability to maintain vascular quiescence by decreased nitric oxide bioavailability through increase in oxidative stress, and upregulation of procoagulant prostaglandins through endothelial COX-2. Third, uremic toxins lead to overexpression of TF in monocytes and endothelial cells, further propagating a prothrombotic phenotype.[51] [52] Despite a hyperthrombotic phenotype, not all CKD patients respond effectively to clopidogrel, an inhibitor of platelet ADP receptor, and a commonly used antiplatelet medication.[49] [50] [53] [54] This is important since poor response to clopidogrel has been associated with increased risk of death, MI, and stent thrombosis in patients undergoing PCI.[55] The antiplatelet effects of aspirin have also been reported to be reduced in patients with CKD,[56] although some studies reported no difference in platelet aggregation in CKD patients compared with non-CKD.[49] While it is currently unknown why some CKD patients do not experience reduced thrombotic risk upon clopidogrel administration, studies suggest that CKD resultant uremia can alter platelet function.[57]

Tryptophan Metabolites and Lysyl Oxidase

CKD is characterized by the accumulation of toxic metabolites due to inability of the kidneys to excrete them properly. Tryptophan is metabolized by bacteria in the intestine to indoles and is further metabolized in the liver to derivatives, such as indoxyl sulfate (IS), that accumulate in patients with CKD, unless dialyzed.[58] Several studies have shown IS to be damaging to endothelial cells, and to induce platelet hyperactivity which may play a role in the risk of thrombosis in CKD.[57] [59] [60] [61] In a CKD mouse model, IS was found to induce platelet hyperactivity largely due to reactive oxygen species (ROS) production.[59] Another mechanism by which IS may facilitate thrombosis in CKD is by upregulating the expression of TF in vascular tissue via the aryl hydrocarbon receptor (ARH).[57] [62] On the other hand, augmented TF is a known risk factor for cardiovascular disease.[63] [64] IS also contributes to cardiovascular disease by promoting the development of atherosclerosis.[65] IS induces phosphorylation of platelet-derived growth factor (PDGF)-β receptors on vascular smooth muscle cells (VSMCs), which leads to the activation of the receptor and subsequent migration and proliferation.[65] Furthermore, IS upregulates the expression of the PDGF-β receptor and sensitizes it to PDGF by generation of ROS through NADPH oxidase-dependent mechanisms.

Another tryptophan metabolite that accumulates in CKD patients is kynurenine (KYN).[66] The rate-limiting enzyme responsible for the degradation of tryptophan to KYN is indoleamine 2,3-dioxygenase 1 (IDO1).[67] Activity of IDO1, as measured by the ratio of KYN:tryptophan, has been associated with progression of CVD and coronary heart disease.[68] [69] Patients with CKD have increased activity of IDO1.[70] [71] [72] One study found a correlation between IDO1 activity and increased carotid artery atherosclerotic plaque size and decreased ankle–brachial index (a marker of peripheral vascular disease) in patients with CKD.[70] A study of 473 patients with advanced CKD demonstrated that patients with subsequent arteriovenous fistula thrombosis had higher levels of KYN compared with those without thrombosis. KYN elevates TF levels in cultured smooth muscle cells.[61] Also of note, KYN plasma levels were reported to predict acute coronary events.[73] Finally, as mentioned earlier, fibrosis is part of CKD progression. In a model of diabetic nephropathy, there is increased LOX expression in the glomerular and tubular areas of the nephron.[74] [75] It is then conceivable that in CKD too, LOX contributes to altered platelet properties, in addition to its effect of tissue fibrosis.

Conclusions and Implication for New Therapeutics

Although we focused on two fibrotic organs as model systems of pathology-induced thrombosis, there are several other examples that follow a similar paradigm. For instance, systemic sclerosis (SSc) is an autoimmune disorder characterized by immune activation, leading to skin and visceral organ fibrosis,[76] with cardiovascular disease and stroke being the most common cause of death.[77] [78] [79] Platelets in SSc patients have increased platelet responsiveness to ADP, serotonin, and collagen,[80] [81] [82] and just as in PMF, tissue and serum LOX is elevated in SSc patients.[83] [84] [85] Therefore, understanding mechanisms of newly identified factors that impact platelet and vascular function in different pathological conditions, and exploring consequences of their pharmacological modulation will offer a window to specific prognostic biomarkers that will (1) advance future development of therapies that target disease-induced atherothrombotic disorders and (2) encourage the general concept of integrating myelofibrosis and other fibrotic organ–specific factors in the global thrombotic and cardiovascular risk assessment. The contribution of nutrition through a low-tryptophan–based diet has the theoretical potential to alter the indole solute-associated risk of thrombotic complications in patients with CKD. Upregulation of LOX in fibrotic organs serves as a potential target for antithrombotic therapy. For instance, it would be interesting to examine the role of LOX in the thrombogenic tendency in a mouse experimental model of CKD. Further, more extensive mechanistic studies are needed in each case to advance disease-specific therapeutic development and personalized care to patients suffering from a variety of thrombogenic pathologies.

Conflict of Interest

None declared.

Acknowledgment

We apologize to authors whose work was not cited due to space limit.

^* These authors contributed equally.

• References

• 1 Leiva O, Ng SK, Chitalia S, Balduini A, Matsuura S, Ravid K. The role of the extracellular matrix in primary myelofibrosis. Blood Cancer J 2017; 7 (02) e525
• 2 Tefferi A, Pardanani A. Myeloproliferative neoplasms: a contemporary review. JAMA Oncol 2015; 1 (01) 97-105
• 3 Falanga A, Marchetti M. Thrombosis in myeloproliferative neoplasms. Semin Thromb Hemost 2014; 40 (03) 348-358
• 4 Barbui T, Carobbio A, Cervantes F. , et al. Thrombosis in primary myelofibrosis: incidence and risk factors. Blood 2010; 115 (04) 778-782
• 5 Kc D, Falchi L, Verstovsek S. The underappreciated risk of thrombosis and bleeding in patients with myelofibrosis: a review. Ann Hematol 2017; 96 (10) 1595-1604
• 6 Rupoli S, Goteri G, Picardi P. , et al. Thrombosis in essential thrombocytemia and early/prefibrotic primary myelofibrosis: the role of the WHO histological diagnosis. Diagn Pathol 2015; 10: 29-36
• 7 Rungjirajittranon T, Owattanapanich W, Ungprasert P, Siritanaratkul N, Ruchutrakool T. A systematic review and meta-analysis of the prevalence of thrombosis and bleeding at diagnosis of Philadelphia-negative myeloproliferative neoplasms. BMC Cancer 2019; 19 (01) 184-192
• 8 Woo KT, Choong HL, Wong KS, Tan HB, Chan CM. The contribution of chronic kidney disease to the global burden of major noncommunicable diseases. Kidney Int 2012; 81 (10) 1044-1045
• 9 Hill NR, Fatoba ST, Oke JL. , et al. Global prevalence of chronic kidney disease - a systematic review and meta-analysis. PLoS One 2016; 11 (07) e0158765
• 10 Wattanakit K, Cushman M. Chronic kidney disease and venous thromboembolism: epidemiology and mechanisms. Curr Opin Pulm Med 2009; 15 (05) 408-412
• 11 Ocak G, Vossen CY, Rotmans JI. , et al. Venous and arterial thrombosis in dialysis patients. Thromb Haemost 2011; 106 (06) 1046-1052
• 12 Arber DA, Orazi A, Hasserjian R. , et al. The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia. Blood 2016; 127 (20) 2391-2405
• 13 Bertozzi I, Bogoni G, Biagetti G. , et al. Thromboses and hemorrhages are common in MPN patients with high JAK2V617F allele burden. Ann Hematol 2017; 96 (08) 1297-1302
• 14 Pei YQ, Wu Y, Wang F, Cui W. Prognostic value of CALR vs. JAK2V617F mutations on splenomegaly, leukemic transformation, thrombosis, and overall survival in patients with primary fibrosis: a meta-analysis. Ann Hematol 2016; 95 (09) 1391-1398
• 15 Lamrani L, Lacout C, Ollivier V. , et al. Hemostatic disorders in a JAK2V617F-driven mouse model of myeloproliferative neoplasm. Blood 2014; 124 (07) 1136-1145
• 16 Etheridge SL, Roh ME, Cosgrove ME. , et al. JAK2V617F-positive endothelial cells contribute to clotting abnormalities in myeloproliferative neoplasms. Proc Natl Acad Sci U S A 2014; 111 (06) 2295-2300
• 17 Versteeg HH, Heemskerk JW, Levi M, Reitsma PH. New fundamentals in hemostasis. Physiol Rev 2013; 93 (01) 327-358
• 18 Furie B, Furie BC. Mechanisms of thrombus formation. N Engl J Med 2008; 359 (09) 938-949
• 19 Watson SP. Collagen receptor signaling in platelets and megakaryocytes. Thromb Haemost 1999; 82 (02) 365-376
• 20 Hollopeter G, Jantzen HM, Vincent D. , et al. Identification of the platelet ADP receptor targeted by antithrombotic drugs. Nature 2001; 409 (6817): 202-207
• 21 Wang Y, Gallant RC, Ni H. Extracellular matrix proteins in the regulation of thrombus formation. Curr Opin Hematol 2016; 23 (03) 280-287
• 22 Xu XR, Carrim N, Neves MA. , et al. Platelets and platelet adhesion molecules: novel mechanisms of thrombosis and anti-thrombotic therapies. Thromb J 2016; 14 (Suppl. 01) 29-38
• 23 Farndale RW, Sixma JJ, Barnes MJ, de Groot PG. The role of collagen in thrombosis and hemostasis. J Thromb Haemost 2004; 2 (04) 561-573
• 24 Angiolillo DJ, Ueno M, Goto S. Basic principles of platelet biology and clinical implications. Circ J 2010; 74 (04) 597-607
• 25 Moroi M, Jung SM, Okuma M, Shinmyozu K. A patient with platelets deficient in glycoprotein VI that lack both collagen-induced aggregation and adhesion. J Clin Invest 1989; 84 (05) 1440-1445
• 26 Kunicki TJ, Ruggeri ZM. Platelet collagen receptors and risk prediction in stroke and coronary artery disease. Circulation 2001; 104 (13) 1451-1453
• 27 Santoso S, Kunicki TJ, Kroll H, Haberbosch W, Gardemann A. Association of the platelet glycoprotein Ia C807T gene polymorphism with nonfatal myocardial infarction in younger patients. Blood 1999; 93 (08) 2449-2453
• 28 Moshfegh K, Wuillemin WA, Redondo M. , et al. Association of two silent polymorphisms of platelet glycoprotein Ia/IIa receptor with risk of myocardial infarction: a case-control study. Lancet 1999; 353 (9150): 351-354
• 29 Carlsson LE, Santoso S, Spitzer C, Kessler C, Greinacher A. The alpha2 gene coding sequence T807/A873 of the platelet collagen receptor integrin alpha2beta1 might be a genetic risk factor for the development of stroke in younger patients. Blood 1999; 93 (11) 3583-3586
• 30 Dodson PM, Haynes J, Starczynski J. , et al. The platelet glycoprotein Ia/IIa gene polymorphism C807T/G873A: a novel risk factor for retinal vein occlusion. Eye (Lond) 2003; 17 (06) 772-777
• 31 Roest M, Banga JD, Grobbee DE. , et al. Homozygosity for 807 T polymorphism in alpha(2) subunit of platelet alpha(2)beta(1) is associated with increased risk of cardiovascular mortality in high-risk women. Circulation 2000; 102 (14) 1645-1650
• 32 Bigalke B, Stellos K, Geisler T, Lindemann S, May AE, Gawaz M. Glycoprotein VI as a prognostic biomarker for cardiovascular death in patients with symptomatic coronary artery disease. Clin Res Cardiol 2010; 99 (04) 227-233
• 33 Alvarez-Larrán A, Arellano-Rodrigo E, Reverter JC. , et al. Increased platelet, leukocyte, and coagulation activation in primary myelofibrosis. Ann Hematol 2008; 87 (04) 269-276
• 34 Gremmel T, Gisslinger B, Gisslinger H, Panzer S. Response to aspirin therapy in patients with myeloproliferative neoplasms depends on the platelet count. Transl Res 2018; 200: 35-42
• 35 Guadall A, Lesteven E, Letort G. , et al. Endothelial cells harbouring the JAK2V617F mutation display pro-adherent and pro-thrombotic features. Thromb Haemost 2018; 118 (09) 1586-1599
• 36 Guy A, Gourdou-Latyszenok V, Le Lay N. , et al. Vascular endothelial cell expression of JAK2^V617F is sufficient to promote a pro-thrombotic state due to increased P-selectin expression. Haematologica 2019; 104 (01) 70-81
• 37 Kogan I, Chap D, Hoffman R, Axelman E, Brenner B, Nadir Y. JAK-2 V617F mutation increases heparanase procoagulant activity. Thromb Haemost 2016; 115 (01) 73-80
• 38 Nadir Y, Brenner B, Zetser A. , et al. Heparanase induces tissue factor expression in vascular endothelial and cancer cells. J Thromb Haemost 2006; 4 (11) 2443-2451
• 39 Edelmann B, Gupta N, Schnoeder TM. , et al. JAK2-V617F promotes venous thrombosis through β1/β2 integrin activation. J Clin Invest 2018; 128 (10) 4359-4371
• 40 Barosi G, Massa M, Campanelli R. , et al. Primary myelofibrosis: older age and high JAK2V617F allele burden are associated with elevated plasma high-sensitivity C-reactive protein levels and a phenotype of progressive disease. Leuk Res 2017; 60: 18-23
• 41 Augello C, Cattaneo D, Bucelli C. , et al. CD18 promoter methylation is associated with a higher risk of thrombotic complications in primary myelofibrosis. Ann Hematol 2016; 95 (12) 1965-1969
• 42 Abbonante V, Chitalia V, Rosti V. , et al. Upregulation of lysyl oxidase and adhesion to collagen of human megakaryocytes and platelets in primary myelofibrosis. Blood 2017; 130 (06) 829-831
• 43 Papadantonakis N, Matsuura S, Ravid K. Megakaryocyte pathology and bone marrow fibrosis: the lysyl oxidase connection. Blood 2012; 120 (09) 1774-1781
• 44 Eliades A, Papadantonakis N, Bhupatiraju A. , et al. Control of megakaryocyte expansion and bone marrow fibrosis by lysyl oxidase. J Biol Chem 2011; 286 (31) 27630-27638
• 45 Matsuura S, Mi R, Koupenova M. , et al. Lysyl oxidase is associated with increased thrombosis and platelet reactivity. Blood 2016; 127 (11) 1493-1501
• 46 Anavekar NS, Pfeffer MA. Cardiovascular risk in chronic kidney disease. Kidney Int Suppl 2004; (92) S11-S15
• 47 Abboud H, Henrich WL. Clinical practice. Stage IV chronic kidney disease. N Engl J Med 2010; 362 (01) 56-65
• 48 Best PJ, Lennon R, Ting HH. , et al. The impact of renal insufficiency on clinical outcomes in patients undergoing percutaneous coronary interventions. J Am Coll Cardiol 2002; 39 (07) 1113-1119
• 49 Jain N, Li X, Adams-Huet B. , et al. Differences in whole blood platelet aggregation at baseline and in response to aspirin and aspirin plus clopidogrel in patients with versus without chronic kidney disease. Am J Cardiol 2016; 117 (04) 656-663
• 50 Gremmel T, Müller M, Steiner S. , et al. Chronic kidney disease is associated with increased platelet activation and poor response to antiplatelet therapy. Nephrol Dial Transplant 2013; 28 (08) 2116-2122
• 51 Addi T, Dou L, Burtey S. Tryptophan-derived uremic toxins and thrombosis in chronic kidney disease. Toxins (Basel) 2018; 10 (10) E412
• 52 Casserly LF, Dember LM. Thrombosis in end-stage renal disease. Semin Dial 2003; 16 (03) 245-256
• 53 Jain N, Hedayati SS, Sarode R, Banerjee S, Reilly RF. Antiplatelet therapy in the management of cardiovascular disease in patients with CKD: what is the evidence?. Clin J Am Soc Nephrol 2013; 8 (04) 665-674
• 54 Tanios BY, Itani HS, Zimmerman DL. Clopidogrel use in end-stage kidney disease. Semin Dial 2015; 28 (03) 276-281
• 55 Aradi D, Komócsi A, Vorobcsuk A. , et al. Prognostic significance of high on-clopidogrel platelet reactivity after percutaneous coronary intervention: systematic review and meta-analysis. Am Heart J 2010; 160 (03) 543-551
• 56 Polzin A, Dannenberg L, Sansone R. , et al. Antiplatelet effects of aspirin in chronic kidney disease patients. J Thromb Haemost 2016; 14 (02) 375-380
• 57 Shashar M, Belghasem ME, Matsuura S. , et al. Targeting STUB1-tissue factor axis normalizes hyperthrombotic uremic phenotype without increasing bleeding risk. Sci Transl Med 2017; 9 (417) eaam8475
• 58 Meijers BK, Evenepoel P. The gut-kidney axis: indoxyl sulfate, p-cresyl sulfate and CKD progression. Nephrol Dial Transplant 2011; 26 (03) 759-761
• 59 Yang K, Du C, Wang X. , et al. Indoxyl sulfate induces platelet hyperactivity and contributes to chronic kidney disease-associated thrombosis in mice. Blood 2017; 129 (19) 2667-2679
• 60 Yang K, Nie L, Huang Y. , et al. Amelioration of uremic toxin indoxyl sulfate-induced endothelial cell dysfunction by Klotho protein. Toxicol Lett 2012; 215 (02) 77-83
• 61 Kolachalama VB, Shashar M, Alousi F. , et al. Uremic solute-aryl hydrocarbon receptor-tissue factor axis associates with thrombosis after vascular injury in humans. J Am Soc Nephrol 2018; 29 (03) 1063-1072
• 62 Gondouin B, Cerini C, Dou L. , et al. Indolic uremic solutes increase tissue factor production in endothelial cells by the aryl hydrocarbon receptor pathway. Kidney Int 2013; 84 (04) 733-744
• 63 Holy EW, Tanner FC. Tissue factor in cardiovascular disease pathophysiology and pharmacological intervention. Adv Pharmacol 2010; 59: 259-292
• 64 Steffel J, Lüscher TF, Tanner FC. Tissue factor in cardiovascular diseases: molecular mechanisms and clinical implications. Circulation 2006; 113 (05) 722-731
• 65 Shimizu H, Hirose Y, Nishijima F, Tsubakihara Y, Miyazaki H. ROS and PDGF-beta [corrected] receptors are critically involved in indoxyl sulfate actions that promote vascular smooth muscle cell proliferation and migration. Am J Physiol Cell Physiol 2009; 297 (02) C389-C396
• 66 Pawlak K, Kowalewska A, Mysliwiec M, Pawlak D. Kynurenine and its metabolites--kynurenic acid and anthranilic acid are associated with soluble endothelial adhesion molecules and oxidative status in patients with chronic kidney disease. Am J Med Sci 2009; 338 (04) 293-300
• 67 Moffett JR, Namboodiri MA. Tryptophan and the immune response. Immunol Cell Biol 2003; 81 (04) 247-265
• 68 Niinisalo P, Raitala A, Pertovaara M. , et al. Indoleamine 2,3-dioxygenase activity associates with cardiovascular risk factors: the Health 2000 study. Scand J Clin Lab Invest 2008; 68 (08) 767-770
• 69 Ozkan Y, Sukuroglu MK, Tulmac M, Kisa U, Simsek B. Relation of kynurenine/tryptophan with immune and inflammatory markers in coronary artery disease. Clin Lab 2014; 60 (03) 391-396
• 70 Kato A, Suzuki Y, Suda T. , et al. Relationship between an increased serum kynurenine/tryptophan ratio and atherosclerotic parameters in hemodialysis patients. Hemodial Int 2010; 14 (04) 418-424
• 71 Schefold JC, Zeden JP, Fotopoulou C. , et al. Increased indoleamine 2,3-dioxygenase (IDO) activity and elevated serum levels of tryptophan catabolites in patients with chronic kidney disease: a possible link between chronic inflammation and uraemic symptoms. Nephrol Dial Transplant 2009; 24 (06) 1901-1908
• 72 Pawlak K, Domaniewski T, Mysliwiec M, Pawlak D. The kynurenines are associated with oxidative stress, inflammation and the prevalence of cardiovascular disease in patients with end-stage renal disease. Atherosclerosis 2009; 204 (01) 309-314
• 73 Eussen SJ, Ueland PM, Vollset SE. , et al. Kynurenines as predictors of acute coronary events in the Hordaland Health Study. Int J Cardiol 2015; 189: 18-24
• 74 Chen J, Ren J, Loo WTY, Hao L, Wang M. Lysyl oxidases expression and histopathological changes of the diabetic rat nephron. Mol Med Rep 2018; 17 (02) 2431-2441
• 75 Stangenberg S, Saad S, Schilter HC. , et al. Lysyl oxidase-like 2 inhibition ameliorates glomerulosclerosis and albuminuria in diabetic nephropathy. Sci Rep 2018; 8 (01) 9423-9432
• 76 Bhattacharyya S, Wei J, Varga J. Understanding fibrosis in systemic sclerosis: shifting paradigms, emerging opportunities. Nat Rev Rheumatol 2011; 8 (01) 42-54
• 77 Elhai M, Meune C, Boubaya M. , et al; EUSTAR group. Mapping and predicting mortality from systemic sclerosis. Ann Rheum Dis 2017; 76 (11) 1897-1905
• 78 Tyndall AJ, Bannert B, Vonk M. , et al. Causes and risk factors for death in systemic sclerosis: a study from the EULAR Scleroderma Trials and Research (EUSTAR) database. Ann Rheum Dis 2010; 69 (10) 1809-1815
• 79 Hesselvig JH, Kofoed K, Wu JJ, Dreyer L, Gislason G, Ahlehoff O. Localized scleroderma, systemic sclerosis and cardiovascular risk: A Danish Nationwide Cohort Study. Acta Derm Venereol 2018; 98 (03) 361-365
• 80 Łukasik ZM, Makowski M, Makowska JS. From blood coagulation to innate and adaptive immunity: the role of platelets in the physiology and pathology of autoimmune disorders. Rheumatol Int 2018; 38 (06) 959-974
• 81 Ramirez GA, Franchini S, Rovere-Querini P, Sabbadini MG, Manfredi AA, Maugeri N. The role of platelets in the pathogenesis of systemic sclerosis. Front Immunol 2012; 3: 160
• 82 Chiang TM, Takayama H, Postlethwaite AE. Increase in platelet non-integrin type I collagen receptor in patients with systemic sclerosis. Thromb Res 2006; 117 (03) 299-306
• 83 Chanoki M, Ishii M, Kobayashi H. , et al. Increased expression of lysyl oxidase in skin with scleroderma. Br J Dermatol 1995; 133 (05) 710-715
• 84 Rimar D, Rosner I, Nov Y. , et al. Brief report: lysyl oxidase is a potential biomarker of fibrosis in systemic sclerosis. Arthritis Rheumatol 2014; 66 (03) 726-730
• 85 Rimar D, Rosner I, Slobodin G. , et al. Lysyl oxidase in systemic sclerosis: getting under the skin. Isr Med Assoc J 2016; 18 (09) 534-536