RESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with the hypercoagulable state. Tissue factor (TF) is the primary cellular initiator of coagulation. Most of the TF expressed on cell surfaces remains cryptic. Sphingomyelin (SM) is responsible for maintaining TF in the encrypted state, and hydrolysis of SM by acid sphingomyelinase (ASMase) increases TF activity. ASMase was shown to play a role in virus infection biology. In the present study, we investigated the role of ASMase in SARS-CoV-2 infection-induced TF procoagulant activity. Infection of human monocyte-derived macrophages (MDMs) with SARS-CoV-2 spike protein pseudovirus (SARS-CoV-2-SP-PV) markedly increased TF procoagulant activity at the cell surface and released TF+ extracellular vesicles. The pseudovirus infection did not increase either TF protein expression or phosphatidylserine externalization. SARS-CoV-2-SP-PV infection induced the translocation of ASMase to the outer leaflet of the plasma membrane, which led to the hydrolysis of SM in the membrane. Pharmacologic inhibitors or genetic silencing of ASMase attenuated SARS-CoV-2-SP-PV-induced increased TF activity. Inhibition of the SARS-CoV-2 receptor, angiotensin-converting enzyme-2, attenuated SARS-CoV-2-SP-PV-induced increased TF activity. Overall, our data suggest that SARS-CoV-2 infection activates the coagulation by decrypting TF through activation of ASMase. Our data suggest that the US Food and Drug Administration-approved functional inhibitors of ASMase may help treat hypercoagulability in patients with COVID-19.
Asunto(s)
COVID-19/sangre , Macrófagos/virología , Proteínas de la Membrana/fisiología , SARS-CoV-2 , Esfingomielina Fosfodiesterasa/fisiología , Glicoproteína de la Espiga del Coronavirus/fisiología , Trombofilia/etiología , Tromboplastina/fisiología , Enzima Convertidora de Angiotensina 2/fisiología , COVID-19/complicaciones , Micropartículas Derivadas de Células , Activación Enzimática , Humanos , Hidrólisis , Macrófagos/enzimología , Terapia Molecular Dirigida , Plásmidos , Transporte de Proteínas , Interferencia de ARN , ARN Interferente Pequeño/genética , Receptores Virales/fisiología , Esfingomielina Fosfodiesterasa/antagonistas & inhibidores , Esfingomielinas/fisiología , Trombofilia/sangre , Trombofilia/tratamiento farmacológico , Trombofilia/enzimologíaRESUMEN
Oxidative status of maternal blood represents an important parameter of pregnancy that is involved in both, regulation of physiological processes and (if significantly altered) development of different pregnancy complications. Inherited thrombophilias represent genetic disorders that increase the risk of thromboembolism in pregnancy. Little is known about the impact of thrombophilia on the oxidative status of maternal blood. In this study, we analyzed oxidative status of blood of 56 women with pregnancies burdened by inherited thrombophilias. The status was established at three different trimesters using biochemical assays and electrochemical measurements, and it was compared to 10 age- and trimester-matching controls. Activities of superoxide dismutase, catalase, and glutathione reductase in the 1st and the 2nd trimester of thrombophilic pregnancy were lower than controls. Also, there was less oxidation in the plasma, according to higher concentration of reduced thiols and lower oxidation-reduction potential. Therefore, it appears that thrombophilic mothers do not experience oxidative stress in the circulation in the first two trimesters. However, the rise in GPx, GR and SOD activities in the 3rd trimester of thrombophilic pregnancy implies that the risk of oxidative stress is increased during the late pregnancy. These results are important for developing antioxidative treatment that could tackle thrombophilia-related pregnancy complications.
Asunto(s)
Complicaciones Hematológicas del Embarazo/sangre , Complicaciones Hematológicas del Embarazo/metabolismo , Trombofilia/sangre , Trombofilia/metabolismo , Adulto , Estudios de Cohortes , Eritrocitos/enzimología , Femenino , Glutatión Peroxidasa/sangre , Humanos , Oxidación-Reducción , Oxidorreductasas/sangre , Embarazo , Complicaciones Hematológicas del Embarazo/enzimología , Trombofilia/enzimologíaRESUMEN
PURPOSE: To investigate the levels of systemic heparanase, inflammatory markers, and coagulation factor activities in patients with retinal vein occlusion (RVO). METHODS: This prospective study included 18 patients with central RVO, 22 patients with branch RVO, and 40 patients with age-related cataract as the control group. Serum heparanase protein levels and activities were measured by ELISA and a heparan degrading enzyme assay kit, respectively. Serum levels of MMP-2, MMP-9, TLR-2, and TLR-4 were measured by ELISA kits. The activities of coagulation factors (V, VII, VIII, and IX) were determined with an autoanalyzer. The Mann-Whitney U test was used to compare the above parameters between patients with RVO and control subjects. The relationship between two of the above parameters was analyzed by Spearman's correlation. RESULTS: Patients with RVO had higher levels of systemic heparanase protein, heparanase activities, coagulation factors' (V, VIII, and IX) activities, MMP-2, MMP-9, TLR-2, and TLR-4 compared with the control group. Systemic heparanase levels were correlated with serum levels of MMP-2, MMP-9, TLR-2, TLR-4, and activities of coagulation factors VIII and IX. CONCLUSION: Increase of systemic heparanase in RVO is associated with activation of systemic inflammation and blood hypercoagulability.
Asunto(s)
Coagulación Sanguínea/fisiología , Glucuronidasa/sangre , Inflamación/sangre , Oclusión de la Vena Retiniana/enzimología , Trombofilia/complicaciones , Biomarcadores/sangre , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inflamación/complicaciones , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Oclusión de la Vena Retiniana/complicaciones , Factores de Riesgo , Trombofilia/enzimologíaRESUMEN
The aim is to study risk factors for retinal vein occlusion (RVO), such as thrombophilic and cardiovascular risk factors (CRF). A retrospective consecutive case series of 60 patients with RVO was made, tested for CRF, hyperhomocysteinemia, lupic anticoagulant, antiphospholipid antibody and 5 gene variants: factor V (FV) Leiden (G1691A), factor II (PT G20210A), 5,1-methylenetetra-hydrofolate reductase (MTHFR; 677 C > T and 1298 A > C), plasminogen activator inhibitor 1 (PAI-1; 4 G/5 G). More than 1 CRF were present in 36 patients (60%), which had a significantly higher mean age at diagnosis (66.7 ± 12.9 versus 59.5 ± 13.7 with ≤1 CRF, [t(57) = -2.05, p = 0.045, d = 0.54). Patients with thermolabile MTHFR forms with decreased enzyme activity (T677T or C677T/A1298C) had a significant lower mean age [57.6 ± 15.1; t (58) = 3.32; p = 0.002; d = 0.846] than patients with normal MTHFR enzyme activity (68.5 ± 10.2). Regarding CRF and thermolabile forms of MTHFR, the mean age at diagnosis could be significantly predicted [F(2,56) = 7.18; p = 0.002] by the equation: 64.8 - 10.3 × (thermolabile MTHFR) - 5.31 × ( ≤ 1CRF). Screening of MTHFR polymorphisms may be useful in younger RVO patients, particularly when multiple CRF are absent.
Asunto(s)
Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo Genético , Oclusión de la Vena Retiniana , Trombofilia , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Oclusión de la Vena Retiniana/enzimología , Oclusión de la Vena Retiniana/etiología , Oclusión de la Vena Retiniana/genética , Factores de Riesgo , Trombofilia/complicaciones , Trombofilia/enzimología , Trombofilia/genéticaRESUMEN
Essentials Microbe-dependent production of trimethylamine N-oxide (TMAO) contributes to thrombosis risk. The impact of host flavin monooxygenase 3 (FMO3) modulation on platelet function is unknown. Genetic manipulation of FMO3 in mice alters systemic TMAO levels and thrombosis potential. Genetic manipulation of FMO3 is associated with alteration of gut microbial community structure. SUMMARY: Background Gut microbes play a critical role in the production of trimethylamine N-oxide (TMAO), an atherogenic metabolite that impacts platelet responsiveness and thrombosis potential. Involving both microbe and host enzymatic machinery, TMAO generation utilizes a metaorganismal pathway, beginning with ingestion of trimethylamine (TMA)-containing dietary nutrients such as choline, phosphatidylcholine and carnitine, which are abundant in a Western diet. Gut microbial TMA lyases use these nutrients as substrates to produce TMA, which upon delivery to the liver via the portal circulation, is converted into TMAO by host hepatic flavin monooxygenases (FMOs). Gut microbial production of TMA is rate limiting in the metaorganismal TMAO pathway because hepatic FMO activity is typically in excess. Objectives FMO3 is the major FMO responsible for host generation of TMAO; however, a role for FMO3 in altering platelet responsiveness and thrombosis potential in vivo has not yet been explored. Methods The impact of FMO3 suppression (antisense oligonucleotide-targeting) and overexpression (as transgene) on plasma TMAO levels, platelet responsiveness and thrombosis potential was examined using a murine FeCl3 -induced carotid artery injury model. Cecal microbial composition was examined using 16S analyses. Results Modulation of FMO3 directly impacts systemic TMAO levels, platelet responsiveness and rate of thrombus formation in vivo. Microbial composition analyses reveal taxa whose proportions are associated with both plasma TMAO levels and in vivo thrombosis potential. Conclusions The present studies demonstrate that host hepatic FMO3, the terminal step in the metaorganismal TMAO pathway, participates in diet-dependent and gut microbiota-dependent changes in both platelet responsiveness and thrombosis potential in vivo.
Asunto(s)
Plaquetas/fisiología , Microbioma Gastrointestinal/fisiología , Hígado/enzimología , Metilaminas/metabolismo , Oxigenasas/fisiología , Trombofilia/enzimología , Animales , Trombosis de las Arterias Carótidas/sangre , Trombosis de las Arterias Carótidas/inducido químicamente , Arteria Carótida Común , Cloruros/toxicidad , Compuestos Férricos/toxicidad , Técnicas de Silenciamiento del Gen , Humanos , Ratones , Ratones Endogámicos C57BL , Oligonucleótidos Antisentido/farmacología , Oxigenasas/antagonistas & inhibidores , Oxigenasas/genética , Plasma Rico en Plaquetas , Ribotipificación , Riesgo , Trombofilia/microbiología , TransgenesRESUMEN
Platelet adhesion to collagen via collagen receptors is an important part of thrombosis. In this issue of Blood, Matsuura et al identify collagen receptors as previously unrecognized targets of the extracellular enzyme lysyl oxidase (LOX), the level of which is increased in myeloproliferative neoplasms (MPNs) and other conditions associated with pathological thromboses.
Asunto(s)
Plaquetas/efectos de los fármacos , Colágeno/farmacología , Activación Plaquetaria/fisiología , Proteína-Lisina 6-Oxidasa/fisiología , Trombofilia/enzimología , AnimalesRESUMEN
Lysyl oxidase (LOX) is overexpressed in various pathologies associated with thrombosis, such as arterial stenosis and myeloproliferative neoplasms (MPNs). LOX is elevated in the megakaryocytic lineage of mouse models of MPNs and in patients with MPNs. To gain insight into the role of LOX in thrombosis and platelet function without compounding the influences of other pathologies, transgenic mice expressing LOX in wild-type megakaryocytes and platelets (Pf4-Lox(tg/tg)) were generated. Pf4-Lox(tg/tg) mice had a normal number of platelets; however, time to vessel occlusion after endothelial injury was significantly shorter in Pf4-Lox(tg/tg) mice, indicating a higher propensity for thrombus formation in vivo. Exploring underlying mechanisms, we found that Pf4-Lox(tg/tg) platelets adhere better to collagen and have greater aggregation response to lower doses of collagen compared with controls. Platelet activation in response to the ligand for collagen receptor glycoprotein VI (cross-linked collagen-related peptide) was unaffected. However, the higher affinity of Pf4-Lox(tg/tg) platelets to the collagen sequence GFOGER implies that the collagen receptor integrin α2ß1 is affected by LOX. Taken together, our findings demonstrate that LOX enhances platelet activation and thrombosis.
Asunto(s)
Plaquetas/efectos de los fármacos , Colágeno/farmacología , Activación Plaquetaria/fisiología , Proteína-Lisina 6-Oxidasa/fisiología , Trombofilia/enzimología , Animales , Plaquetas/citología , Traumatismos de las Arterias Carótidas/complicaciones , Trombosis de las Arterias Carótidas/etiología , Integrina alfa2beta1/fisiología , Megacariocitos/enzimología , Ratones , Ratones Transgénicos , Fragmentos de Péptidos/farmacología , Adhesividad Plaquetaria/genética , Adhesividad Plaquetaria/fisiología , Agregación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/genética , Factor Plaquetario 4/genética , Regiones Promotoras Genéticas , Proteína-Lisina 6-Oxidasa/genética , Ratas , Trombofilia/genéticaRESUMEN
Previous studies suggest that cyclooxygenase-2 (COX-2) might influence megakaryocyte (MK) maturation and platelet production in vitro. Using a gene deletion model, we analysed the effect of COX-2 deficiency on megakaryopoiesis and platelet function. COX-2-/- mice (10-12 weeks old) have hyper-responsive platelets as suggested by their enhanced aggregation, TXA2 biosynthesis, CD62P and CD41/CD61 expression, platelet-fibrinogen binding, and increased thromboembolic death after collagen/epinephrine injection compared to wild-type (WT). Moreover, increased platelet COX-1 expression and reticulated platelet fraction were observed in COX-2-/- mice while platelet count was similar to WT. MKs were significantly reduced in COX-2-/- bone marrows (BMs), with high nuclear/cytoplasmic ratios, low ploidy and poor expression of lineage markers of maturation (CD42d, CD49b). However, MKs were significantly increased in COX-2-/- spleens, with features of MK maturation markers which were not observed in MKs of WT spleens. Interestingly, the expression of COX-1, prostacyclin and PGE2 synthases and prostanoid pattern were modified in BMs and spleens of COX-2-/- mice. Moreover, COX-2 ablation reduced the percentage of CD49b+ cells, the platelet formation and the haematopoietic stem cells in bone marrow and increased their accumulation in the spleen. Splenectomy decreased peripheral platelet number, reverted their hyper-responsive phenotype and protected COX-2-/- mice from thromboembolism. Interestingly, fibrosis was observed in spleens of old COX-2-/- mice (28 weeks old). In conclusion, COX-2 deletion delays BM megakaryopoiesis promoting a compensatory splenic MK hyperplasia, with a release of hyper-responsive platelets and increased thrombogenicity in vivo. COX-2 seems to contribute to physiological MK maturation and pro-platelet formation.
Asunto(s)
Plaquetas/fisiología , Ciclooxigenasa 2/deficiencia , Trombopoyesis/fisiología , Animales , Antígenos CD/biosíntesis , Antígenos CD/genética , Antígenos de Diferenciación/biosíntesis , Antígenos de Diferenciación/genética , Médula Ósea/metabolismo , Médula Ósea/patología , Cruzamientos Genéticos , Ciclooxigenasa 1/biosíntesis , Ciclooxigenasa 1/genética , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/fisiología , Células Madre Hematopoyéticas/metabolismo , Células Madre Hematopoyéticas/patología , Hiperplasia , Megacariocitos/metabolismo , Megacariocitos/ultraestructura , Proteínas de la Membrana/biosíntesis , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Recuento de Plaquetas , Ploidias , Púrpura Trombocitopénica Idiopática/fisiopatología , Púrpura Trombocitopénica Idiopática/cirugía , Receptores de Tromboxano A2 y Prostaglandina H2/biosíntesis , Receptores de Tromboxano A2 y Prostaglandina H2/genética , Bazo/metabolismo , Bazo/patología , Esplenectomía , Tromboembolia/inducido químicamente , Tromboembolia/etiología , Tromboembolia/prevención & control , Trombofilia/enzimología , Trombofilia/genética , Tromboxano B2/sangreRESUMEN
INTRODUCTION: Warfarin is characterized by a large inter-individual variability in dosage requirement. This study aimed to analyze the contribution of the CYP4F2 genetic polymorphism and plasma vitamin K concentration on the warfarin pharmacodynamics in patients and to clarify the plasma vitamin K concentration affecting warfarin sensitivity index in rats. MATERIALS AND METHODS: Genetic analyses of selected genes were performed and plasma concentrations of warfarin, vitamin K1 (VK1) and menaquinone-4 (MK-4) were measured in 217 Japanese patients. We also assessed the association of plasma VK1 and MK-4 concentrations with the warfarin sensitivity index (INR/Cp) in rats. RESULTS: Patients with the CYP4F2 (rs2108622) TT genotype had significantly higher plasma VK1 and MK-4 concentrations than those with CC and CT genotypes. The multiple linear regression model including VKORC1, CYP4F2, and CYP2C9 genetic variants, age, and weight could explain 42% of the variability in warfarin dosage. The contribution of CYP4F2 polymorphism was estimated to be 2.2%. In contrast, plasma VK1 and MK-4 concentrations were not significantly associated with warfarin dosage in patients. Nevertheless, we were able to demonstrate that the warfarin sensitivity index was attenuated and negatively correlated with plasma VK1 concentration by the oral administration of VK1 in rats, as it resulted in a higher VK1 concentration than that in patients. CONCLUSIONS: The plasma VK1 and MK-4 concentrations are significantly influenced by CYP4F2 genetic polymorphism but not associated with warfarin therapy at the observed concentration in Japanese patients. The CYP4F2 polymorphism is poorly associated with inter-individual variability of warfarin dosage requirement.
Asunto(s)
Anticoagulantes/farmacocinética , Sistema Enzimático del Citocromo P-450/genética , Polimorfismo de Nucleótido Simple , Vitamina K 1/sangre , Vitamina K 2/análogos & derivados , Warfarina/farmacocinética , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Animales , Anticoagulantes/administración & dosificación , Anticoagulantes/uso terapéutico , Pueblo Asiatico/genética , Biotransformación/genética , Citocromo P-450 CYP2C9/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Sistema Enzimático del Citocromo P-450/fisiología , Familia 4 del Citocromo P450 , Resistencia a Medicamentos/genética , Femenino , Variación Genética/genética , Genotipo , Humanos , Relación Normalizada Internacional , Masculino , Persona de Mediana Edad , Ratas , Ratas Sprague-Dawley , Trombofilia/tratamiento farmacológico , Trombofilia/enzimología , Vitamina K 1/antagonistas & inhibidores , Vitamina K 2/antagonistas & inhibidores , Vitamina K 2/sangre , Vitamina K Epóxido Reductasas/genética , Warfarina/administración & dosificación , Warfarina/uso terapéutico , Adulto JovenRESUMEN
Venous thromboembolism is known to be a complex interaction of genetic and acquired factors leading to thrombosis. JAK2V617F mutation is believed to contribute to a thrombophilic phenotype, possibly through enhanced leukocyte-platelet interactions in myeloproliferative neoplasms (MPNs). Several studies have focused on the importance of screening for JAK2V617F mutation in patients with splanchnic venous thrombosis (VT) for the detection of nonovert MPNs. The role of JAK2V617F mutation in VT outside the splanchnic region is still widely unsettled. The primary aim of this study was to find out the prevalence of JAK2V617F mutation in patients with deep venous thrombosis (DVT), its clinical significance as a prothrombotic risk factor, and its possible interactions with other genetic thrombophilic risk factors. A total of 148 patients with idiopathic, symptomatic DVT were evaluated. Median age of presentation was 32 years (range 15-71 years) with a sex ratio of 1.3:1. Overall, the most common genetic prothrombotic factor was factor V Leiden mutation, found in 10.8% (16 of 148) of patients who also showed strong association with increased risk of thrombosis (odds ratio 5.94, confidence interval 1.33-26.4, P = .019). Deficiencies in protein C, protein S, and antithrombin were seen in 8 (5.4%), 10 (6.7%), and 8 (5.4%) patients, respectively. It was observed that the frequency of JAK2V617F mutation was lower in Indian patients, and it also showed weaker association with risk of thrombosis, at least in cases of venous thrombosis outside the splanchnic region.
Asunto(s)
Janus Quinasa 2/genética , Mutación Missense , Trombofilia/genética , Trombosis de la Vena/genética , Adolescente , Adulto , Anciano , Sustitución de Aminoácidos , Femenino , Humanos , India/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Prospectivos , Factores de Riesgo , Trombofilia/enzimología , Trombofilia/epidemiología , Trombosis de la Vena/enzimología , Trombosis de la Vena/epidemiologíaRESUMEN
JAK 2 mutation is the molecular event responsible for 95% of polycythemia cases and 50% of thrombocythemia vera and myelofibrosis cases. It can be used as a tool for the diagnosis of myeloproliferative disorders. We report a case illustrating the fact that a negative result does not definitively eliminate the diagnosis. A 40-year old woman, with a medical history of familial deep vein thrombosis, developed thrombosis of the inferior vena cava with extension to the suprahepatic veins and pulmonary embolism. No constitutional or acquired thrombophilia was diagnosed; search for JAK 2 mutation was negative. The patient was treated with fluindione. Five years later, she relapsed with popliteo-femoral and vena cava deep vein thrombosis. The etiological work-up included a PET scan which revealed diffuse uptake in bones and suspected neoplasic bone marrow invasion. Progenitor cell cultures were positive and JAK 2 mutation was confirmed. The bone marrow aspirate had the cytologic appearance of a myeloproliferative disorder. This case illustrates the fact that JAK 2 mutation can be identified several years after onset of a latent myeloproliferative disorder. Cases with a high clinical likelihood should lead to renewed search for this mutation. Secondary discovery of this mutation can be explained by a higher proportion of mutation expressing clones.
Asunto(s)
Janus Quinasa 2/genética , Mutación Missense , Trastornos Mieloproliferativos/diagnóstico , Mutación Puntual , Trombosis de la Vena/etiología , Adulto , Anticoagulantes/uso terapéutico , Médula Ósea/patología , Eritroblastos/patología , Femenino , Humanos , Megacariocitos/patología , Trastornos Mieloproliferativos/complicaciones , Trastornos Mieloproliferativos/genética , Trastornos Mieloproliferativos/patología , Fenindiona/análogos & derivados , Fenindiona/uso terapéutico , Embolia Pulmonar/etiología , Recurrencia , Trombofilia/enzimología , Trombofilia/genética , Talasemia alfa/genéticaRESUMEN
We present the case of a patient with left atrial myxoma that presented with pulmonary embolism. The patient did not have any intracardiac communication between right and left sides of the heart. Using thrombelastography, the patient was determined to have an abnormally large velocity of plasma thrombus growth and strength with reduced vulnerability to lysis. Critically, increased carboxyhemoglobin concentrations were present, likely secondary to hemolysis from the tumor and engagement of systemic heme oxygenase-1. It was determined that the patient's plasmatic hypercoagulability was in part due to carboxyhemefibrinogen formation via a thrombelastographic method. In addition to circulating hypercoagulability, the patient also had an area of chronic venous stasis in his left ankle that had not changed for over a decade prior to this thrombophilic episode. In conclusion, we present the first case of paradoxical pulmonary embolism in the presence of a left atrial myxoma, potentially secondary to a combination of hemolysis, heme oxygenase-1 up-regulation, systemic hypercoagulability/hypofibrinolysis, and regional venous stasis.
Asunto(s)
Neoplasias Cardíacas/enzimología , Hemo-Oxigenasa 1/sangre , Mixoma/enzimología , Embolia Pulmonar/enzimología , Trombofilia/enzimología , Anciano , Carboxihemoglobina/metabolismo , Atrios Cardíacos/enzimología , Atrios Cardíacos/patología , Neoplasias Cardíacas/complicaciones , Neoplasias Cardíacas/diagnóstico , Neoplasias Cardíacas/patología , Hemo-Oxigenasa 1/genética , Humanos , Masculino , Mixoma/complicaciones , Mixoma/diagnóstico , Mixoma/patología , Embolia Pulmonar/complicaciones , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/patología , Tromboelastografía , Trombofilia/complicaciones , Trombofilia/diagnóstico , Trombofilia/patología , Regulación hacia ArribaRESUMEN
OBJECTIVES: Lung cancer is an important health threat worldwide, and is associated with a 3.8-13.9% incidence of thrombophilia. Of interest, patients with lung tumors have been noted to have an increase in endogenous carbon monoxide production via upregulation of hemeoxygenase-1 activity. Given that it has been demonstrated that carbon monoxide enhances plasmatic coagulation in vitro and in vivo via formation of carboxyhemefibrinogen, we sought to determine if patients with thoracic tumors undergoing lung resection/pneumonectomy had an increase in endogenous carbon monoxide and concurrent plasmatic hypercoagulability. MATERIALS AND METHODS: Nonsmoking patients with thoracic tumors (n=19) had preoperative carboxyhemoglobin (a measure of carbon monoxide production) determined, and a thromboelastometric method to assess citrated plasma coagulation kinetics and the formation of carboxyhemefibrinogen was utilized. Thoracic tumor patient coagulation kinetics was compared with normal subject (n=30) plasma samples. RESULTS AND CONCLUSION: Patients with thoracic tumors were determined to have an abnormally increased carboxyhemoglobin concentration of 2.1±0.6%, indicative of hemeoxygenase-1 upregulation. It was found that 84% of thoracic tumor patients had plasma clot strength that exceeded the 95% confidence interval value observed in normal subjects, and 44% of this hypercoagulable subgroup had carboxyhemefibrinogen formation. Future investigation of the role played by plasmatic hypercoagulability and hemeoxygenase-1 derived carboxyhemefibrinogen in the pathogenesis of thoracic tumor related thrombophilia is warranted.
Asunto(s)
Hemo-Oxigenasa 1/metabolismo , Neoplasias Torácicas/enzimología , Neoplasias Torácicas/epidemiología , Trombofilia/enzimología , Trombofilia/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Coagulación Sanguínea , Monóxido de Carbono/metabolismo , Carboxihemoglobina/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Torácicas/sangre , Tromboelastografía , Trombofilia/sangre , Regulación hacia Arriba , Adulto JovenRESUMEN
Thyroid cancers can cause significant regional thrombotic morbidity and mortality. Of interest, thyroid cancer cell lines can have upregulation of the carbon monoxide-producing enzyme, hemeoxygenase-1. Carbon monoxide has been demonstrated to markedly enhance plasmatic coagulation in vitro and in vivo via enhancement of fibrinogen's substrate properties by binding to a fibrinogen-associated heme group(s). We present a patient undergoing removal of a malignant thyroid tumour who was serendipitously found to have abnormally increased carboxyhaemoglobin concentration (2.4%) and plasmatic hypercoagulability with a carbon monoxide-mediated clot strength as determined by a thrombelastographic method. This initial observation serves as a rationale to further investigate the role played by hemeoxygenase-1 upregulation in the setting of cancers associated with increased endogenous carbon monoxide production.
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Hemo-Oxigenasa 1/metabolismo , Trombofilia/sangre , Trombofilia/enzimología , Neoplasias de la Tiroides/sangre , Neoplasias de la Tiroides/enzimología , Anciano , Femenino , Humanos , Tromboelastografía/métodosRESUMEN
Inherited thrombophilias are thought to play an important role in the cause of pulmonary embolism and its recurrence. Ninety of 281 patients objectively diagnosed as pulmonary embolism between 2006 and 2009 were included in the study. The screening for thrombophilia included mutations of factor V Leiden (FVL), prothrombin (PTM) G20210A, methylene tetrahydrofolate reductase C677T-A1298C, the serum levels of antithrombin III, protein C, protein S, factor VIII and activated protein C resistance. Forty-two male (46.7%) and 48 female (53.3%) patients had a mean age of 62.6â±â13.4 years. Patients with common thrombophilias comprised 30% of all cases (FVL: 19.1%, PTM G20210A: 3.4%, antithrombin III deficiency: 1.1%, protein C deficiency: 5.7%, protein S deficiency: 13.6%). A significant association between recurrence of pulmonary embolism (10 patients, 12.2%) and protein S deficiency was established (Pâ=â0.040). Serum level of protein C was also significantly lower in the subgroup of recurrent pulmonary embolism (Pâ=â0.049). FVL and PTM mutations were high in cancer patients; the presence of inherited thrombophilia was low with risk factors of surgery and immobilization. Genetic risk factors were high in patients with pulmonary embolism. Protein C and S deficiencies may play a role in pulmonary embolism recurrence. DVT or family history of pulmonary embolism was not found to be related to inherited thrombophilias. Surgery and immobilization were thought not to have priorities for detection of genetic risk factors. The high percentages of FVL and PTM mutations in cancer patients should be considered.
Asunto(s)
Embolia Pulmonar/sangre , Embolia Pulmonar/genética , Trombofilia/sangre , Trombofilia/genética , Factor V/metabolismo , Femenino , Humanos , Masculino , Metilenotetrahidrofolato Reductasa (NADPH2)/metabolismo , Persona de Mediana Edad , Protrombina/metabolismo , Embolia Pulmonar/enzimología , Factores de Riesgo , Trombofilia/enzimologíaRESUMEN
The study covered the impact of modes of preparation of plasma samples to arrange the thrombin generation test for the purpose to establish adequately the hypercoagulation status. The optimal regimen is determined to prepare the samples to be used in the study. The group of females was involved into the study to take the composite oral contraceptives to demonstrate the possibility to apply the thrombin generation test to reveal the hypercoagulation.
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Pruebas Enzimáticas Clínicas/métodos , Trombina/análisis , Trombofilia/diagnóstico , Adulto , Trastornos de la Coagulación Sanguínea/diagnóstico , Trastornos de la Coagulación Sanguínea/enzimología , Anticonceptivos Orales/efectos adversos , Femenino , Humanos , Persona de Mediana Edad , Embarazo , Trombofilia/enzimología , Trombosis/inducido químicamenteRESUMEN
The recently discovered JAK2 V617F point mutation, found in 50-60% of ET patients, has been reported to be associated with a higher risk of thrombotic events. In this study, we explored if JAK2 V617F mutation, or coexisting thrombophilic and hemostatic risk factors, contributed to these complications. We examined 32 patients with ET, and looked for pathogenetic JAK2 V617F mutation and prothrombotic genes mutations: factor V Leiden, prothrombin and MTHFR. We also evaluated plasma levels of fibrinogen, factors VIII and XII, AT, protein C, protein S and serum level of homocysteine. Urokinase concentration was assessed in patients' plasma as well as platelet lysates. There was no difference in the number of thrombotic complications between ET patients with and without JAK2 mutation. However, we found a number of thrombophilic and hemostatic risk factors that could contribute to thrombotic complications in ET patients.
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Hemostasis/genética , Janus Quinasa 2/genética , Mutación Puntual/genética , Trombocitemia Esencial/complicaciones , Trombocitemia Esencial/enzimología , Trombofilia/complicaciones , Trombofilia/enzimología , Factores de Coagulación Sanguínea , Estudios de Casos y Controles , Femenino , Predisposición Genética a la Enfermedad , Hemorragia/complicaciones , Hemorragia/enzimología , Hemorragia/genética , Humanos , Masculino , Persona de Mediana Edad , Factores de Riesgo , Trombocitemia Esencial/genética , Trombofilia/genéticaRESUMEN
BACKGROUND: A deficiency of specific glycosylphosphatidyl inositol-anchored proteins in paroxysmal nocturnal hemoglobinuria may be responsible for most of the clinical features of this disease, but some functional consequences may be indirect. For example, the absence of certain glycosylphosphatidyl inositol-anchored proteins in paroxysmal nocturnal hemoglobinuria cells may influence expression of other membrane proteins. Membrane-bound proteinase 3 co-localizes with glycosylphosphatidyl inositol-linked neutrophil antigen 2a, which is absent in patients with paroxysmal nocturnal hemoglobinuria. DESIGN AND METHODS: We compared expression of proteinase 3 and neutrophil antigen 2a by flow cytometry and western blotting in normal and paroxysmal nocturnal hemoglobinuria cells and measured cytoplasmic and soluble levels of proteinase 3 by enzyme-linked immunosorbent assays in controls and patients with paroxysmal nocturnal hemoglobinuria. Finally, we studied the effects of proteinase 3 on platelet activation using an in vitro aggregometry assay and flow cytometry. RESULTS: We showed that membrane-bound proteinase 3 is deficient in patients' cells, but invariantly present in the cytoplasm regardless of disease phenotype. When we isolated lipid rafts from patients, both molecules were detected only in the rafts from normal cells, but not diseased ones. Membrane-bound proteinase 3 was associated with a decrease in plasma proteinase 3 levels, clone size and history of thrombosis. In addition, we found that treating platelets ex vivo with proteinase 3, but not other agonists, decreased the exposure of an epitope on protease activated receptor-1 needed for thrombin activation. Conversely, treatment of whole blood with serine protease inhibitor enhanced expression of this epitope on protease activated receptor-1 located C-terminal to the thrombin cleavage site on platelets. CONCLUSIONS: We demonstrated that deficiency of glycosylphosphatidyl inositol-anchored proteins in paroxysmal nocturnal hemoglobinuria results in decreased membrane-bound and soluble proteinase 3 levels. This phenomenon may constitute another mechanism contributing to a prothrombotic propensity in patients with paroxysmal nocturnal hemoglobinuria.
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Regulación Enzimológica de la Expresión Génica , Hemoglobinuria Paroxística/complicaciones , Hemoglobinuria Paroxística/enzimología , Mieloblastina/metabolismo , Trombofilia/enzimología , Trombofilia/etiología , Plaquetas/metabolismo , Citoplasma/enzimología , Proteínas Ligadas a GPI/metabolismo , Hemoglobinuria Paroxística/sangre , Hemoglobinuria Paroxística/genética , Humanos , Isoantígenos/metabolismo , Microdominios de Membrana/metabolismo , Proteínas de la Membrana/metabolismo , Mieloblastina/sangre , Receptores de Superficie Celular/metabolismo , Trombina/metabolismoRESUMEN
BACKGROUND: Thrombelastography (TEG) allows for rapid global assessment of coagulation function. Our previous work demonstrated that a hypercoagulable state identified by TEG's G value was associated with thromboembolic events in a cohort of critically ill surgical patients despite routine chemoprophylaxis. We hypothesized that a hypercoagulable state could be differentiated into enzymatic or platelet etiology through the use of thrombus velocity curves; specifically the time to maximum rate of thrombus generation (TMRTG) and the novel TEG parameter, delta. (Delta) METHODS: We retrospectively studied 10 critically ill surgical patients receiving thromboprophylaxis for at least 72 h by TEG, using kaolin activated citrated samples. Thrombus velocity curves were plotted for each patient, and delta was calculated as the difference between the TEG parameters R and SP, corresponding to the time to maximum rate of thrombus generation (TMRTG), which reflects the enzymatic contribution to clot formation. The TEG parameter G, (G = 5000 x A/100-A) also was determined for each patient. As G is derived from amplitude (A), it reflects overall net clot strength. A hypercoagulable state was defined as delta < 0.6 min and/or G > 11 dynes/cm(2). RESULTS: A hypercoagulable state was identified via delta in 6 patients (60%); all of whom remained hypercoagulable following heparinase addition, suggesting chemoprophylaxis was ineffective. Of six patients with a hypercoagulable G value, 50% had a normal delta suggesting the presence of platelet hypercoagulability. Delta closely correlated with TMRTG (r = 0.94). However, the varying contribution of platelets to hypercoagulability, was shown by a nonlinear, weak correlation of delta and TMRTG with G (r = 0.11 and r = 0.14, respectively). CONCLUSION: Delta reflects changes in thrombin generation as measured by TMRTG, allowing for differentiation of enzymatic from platelet hypercoagulability. Future studies will be required to validate these findings.
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Tromboelastografía , Trombofilia/diagnóstico , Trombofilia/etiología , Adulto , Plaquetas/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Retrospectivos , Trombofilia/enzimologíaRESUMEN
The clinical course of the classic myeloproliferative neoplasms (MPNs) is burdened by an increased rate of cardiovascular events, which are the major cause of mortality. Age and history of thrombosis are the criteria used to stratify patients to the most appropriate therapeutic options. However, the mechanisms ultimately responsible for the increased thrombotic tendency have not yet been elucidated; abnormalities of blood cell count, neutrophil and platelet activation, and a state of hypercoagulability can all occur. Recurrent mutations in JAK2 or MPL have been described in MPNs and serve as disease markers. There is also evidence that a JAK2V617F mutant state represents an independent factor associated with thrombosis, and abnormalities of cell function attributable to JAK2V617F have been characterized. It is hoped that elucidation of the role mutant JAK2 plays in MPNs will improve our understanding of the pathophysiology of thrombosis and eventually result in improved patient treatment using molecularly targeted drugs.