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1.
Blood Adv ; 6(17): 5198-5209, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36069828

RESUMO

Von Willebrand factor (VWF) is a multimeric plasma glycoprotein that is critically involved in hemostasis. Biosynthesis of long VWF concatemers in the endoplasmic reticulum and the trans-Golgi is still not fully understood. We use the single-molecule force spectroscopy technique magnetic tweezers to analyze a previously hypothesized conformational change in the D'D3 domain crucial for VWF multimerization. We find that the interface formed by submodules C8-3, TIL3, and E3 wrapping around VWD3 can open and expose 2 buried cysteines, Cys1099 and Cys1142, that are vital for multimerization. By characterizing the conformational change at varying levels of force, we can quantify the kinetics of the transition and stability of the interface. We find a pronounced destabilization of the interface on lowering the pH from 7.4 to 6.2 and 5.5. This is consistent with initiation of the conformational change that enables VWF multimerization at the D'D3 domain by a decrease in pH in the trans-Golgi network and Weibel-Palade bodies. Furthermore, we find a stabilization of the interface in the presence of coagulation factor VIII, providing evidence for a previously hypothesized binding site in submodule C8-3. Our findings highlight the critical role of the D'D3 domain in VWF biosynthesis and function, and we anticipate our methodology to be applicable to study other, similar conformational changes in VWF and beyond.


Assuntos
Complexo de Golgi , Fator de von Willebrand , Sítios de Ligação , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Domínios Proteicos , Fator de von Willebrand/metabolismo
2.
Cells ; 11(17)2022 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-36078114

RESUMO

The aim of this study was to evaluate the effect of acute aldosterone (ALDO) administration on the vascular permeability of skin. ALDO was injected intradermally into rats, and vascular permeability was measured. Eplerenone (EPL), a selective mineralocorticoid receptor (MR) antagonist, was used. Skin biopsies were carried out for immunohistochemical (IHC) staining, and polymerase chain reactions were performed to analyze the expression of MR, 11ß-hydroxysteroid dehydrogenase type 2, von Willebrand factor (vWF), vascular endothelial growth factor (VEGF), and zonula occludens 1. Our study showed the presence of MR in the rat skin vasculature for the first time. It was found that ALDO injection resulted in a more than 30% increase in vascular permeability and enhanced the endothelial exocytosis of vWF. The effect of ALDO diminished after EPL administration. An accumulation of vWF and a reduction in VEGF IHC staining were observed following chronic EPL administration. No effect of ALDO or EPL on the mRNA expression of the studied genes or skin structure was observed. The results suggest that ALDO increases vascular permeability in the skin via an MR-dependent mechanism. This effect of ALDO on skin microcirculation may have important therapeutic implications for diseases characterized by increased levels of ALDO and coexisting skin microangiopathy.


Assuntos
Aldosterona , Fator A de Crescimento do Endotélio Vascular , Aldosterona/metabolismo , Aldosterona/farmacologia , Animais , Permeabilidade Capilar , Eplerenona , Antagonistas de Receptores de Mineralocorticoides , Ratos , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/metabolismo
3.
Proc Natl Acad Sci U S A ; 119(34): e2207592119, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35969769

RESUMO

Vaso-occlusive episode (VOE) is a common and critical complication of sickle cell disease (SCD). Its pathogenesis is incompletely understood. von Willebrand factor (VWF), a multimeric plasma hemostatic protein synthesized and secreted by endothelial cells and platelets, is increased during a VOE. However, whether and how VWF contributes to the pathogenesis of VOE is not fully understood. In this study, we found increased VWF levels during tumor necrosis factor (TNF)-induced VOE in a humanized mouse model of SCD. Deletion of endothelial VWF decreased hemolysis, vascular occlusion, and organ damage caused by TNF-induced VOE in SCD mice. Moreover, administering ADAMTS13, the VWF-cleaving plasma protease, reduced plasma VWF levels, decreased inflammation and vaso-occlusion, and alleviated organ damage during VOE. These data suggest that promoting VWF cleavage via ADAMTS13 may be an effective treatment for reducing hemolysis, inflammation, and vaso-occlusion during VOE.


Assuntos
Anemia Falciforme , Doenças Vasculares , Fator de von Willebrand , Proteína ADAMTS13/metabolismo , Proteína ADAMTS13/farmacologia , Proteína ADAMTS13/uso terapêutico , Animais , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Deleção de Genes , Hemólise/efeitos dos fármacos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Camundongos , Doenças Vasculares/tratamento farmacológico , Doenças Vasculares/etiologia , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
4.
J Med Case Rep ; 16(1): 326, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35999558

RESUMO

BACKGROUND: We speculated that subclinical thrombosis may occur frequently through crosstalk between immune/inflammatory reactions and hemostasis after corona virus disease-2019 (COVID-19) vaccination. To test this hypothesis, we measured thrombosis-related parameters after COVID-19 vaccination in a volunteer for 21 days. CASE PRESENTATION: The following parameters were measured in a 72-year-old Korean man at 1 day before vaccination and on days 1, 3, 7, 14, and 21 post vaccination (AstraZeneca COVID-19 vaccine: ChAdOx1-S/nCoV-19, CTMAV563): complete blood count, platelet indices, thrombin receptor-activating peptide-induced platelet aggregation, prothrombin time, activated partial thromboplastin time, D-dimer, thrombin-antithrombin III complex (TAT), plasmin-α2 antiplasmin complex (PAP), von Willebrand factor (vWF) antigen and activity, plasminogen activator inhibitor-1 (PAI-1), protein C and protein S antigen and activity, lupus anticoagulant, fibrinogen degradation product, and plasminogen. We found that the TAT had significantly increased from 0.7 ng/mL (baseline) to 21.7 ng/mL (day 1). There was a transient increase in the PAI-1 level from 7.2 ng/mL (baseline) to 10.9 ng/mL (day 3), followed by a decrease in PAP level from 0.9 ng/mL (baseline) to 0.3 µg/mL (day 7), suggesting that plasmin generation is suppressed by PAI-1. CONCLUSIONS: Increased thrombotic factors (such as decreased protein S) and decreased fibrinolytic activity due to increased PAI-1 were potential factors causing thrombogenesis after COVID-19 vaccination. Sequential measurement of platelet indices, TAT, PAP, protein C, protein S, vWF, D-dimer, and PAI-1 following COVID-19 vaccination was informative.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Trombose , Vacina de mRNA-1273 contra 2019-nCoV , Idoso , Vacinas contra COVID-19/efeitos adversos , ChAdOx1 nCoV-19 , Fibrinolisina/metabolismo , Humanos , Masculino , Inibidor 1 de Ativador de Plasminogênio , Proteína C/metabolismo , Proteína S , Trombose/etiologia , Vacinação , Voluntários , Fator de von Willebrand/metabolismo
5.
PLoS One ; 17(8): e0273312, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36037218

RESUMO

The stress distribution along the trajectories of passive particles released in turbulent flow were computed with the use of Lagrangian methods and direct numerical simulations. The flow fields selected were transitional Poiseuille-Couette flow situations found in ventricular assist devices and turbulent flows at conditions found in blood pumps. The passive particle properties were selected to represent molecules of the von Willebrand factor (vWF) protein. Damage to the vWF molecule can cause disease, most often related to hemostasis. The hydrodynamic shear stresses along the trajectories of the particles were calculated and the changes in the distribution of stresses were determined for proteins released in different locations in the flow field and as a function of exposure time. The stress distributions indicated that even when the average applied stress was within a safe operating regime, the proteins spent part of their trajectories in flow areas of damaging stress. Further examination showed that the history of the distribution of stresses applied on the vWF molecules, rather than the average, should be used to evaluate hydrodynamically-induced damage.


Assuntos
Coração Auxiliar , Fator de von Willebrand , Hemostasia , Hidrodinâmica , Estresse Mecânico , Fator de von Willebrand/metabolismo
6.
Medicine (Baltimore) ; 101(31): e29854, 2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-35945712

RESUMO

Heart failure with preserved ejection fraction (HFpEF) is associated with endothelial damage and inflammation. In addition, von Willebrand factor (vWF) has been discovered as a biomarker of endothelial dysfunction. Therefore, the study aims to investigate the association between vWF level and HFpEF. Moreover, we analyzed a potential correlation between vWF and inflammatory factors, such as C-reactive protein (CRP), tumor necrosis factor-alpha (TNF-α), and interleukin (IL)-6. We recruited altogether 272 hospitalized patients from The Fifth Affiliated Hospital of Xinjiang Medical University, 88 of whom were HFpEF patients, 88 were non-heart failure patients, and 96 were healthy controls from the medical examination center of the hospital. Enzyme-linked immunosorbent assay and double antibody sandwich immunochromatography were used for testing vWF, tissue plasminogen activator, galectin-3, nitric oxide, TNF-α, IL-6, and CRP. The HFpEF group's levels of vWF, IL-6, TNF-α, CRP, tissue plasminogen activator, galectin-3, and nitric oxide were statistically higher than those of non-heart failure and healthy control ones (F = 403.563, 21.825, 20.678, 39.609, 35.411, 86.407, 74.605; all P = .000). the highest level of vWF was observed in class IV (New York Heart Association) of HFpEF patients and the significant difference is <.05 (P < .001). An increasing level of vWF were shown in groups (CRP: CRP >3 mg/L group and CRP ≤3 mg/L group; IL-6: IL-6 <7.0 pg/mL group and IL-6 ≥7.0 pg/mL group; TNF-α: TNF-α <5.5 pg/mL group and TNF-α ≥5.5 pg/mL group) with higher level of IL-6, TNF-α, CRP. A multiple regression analysis regarding the relationship of vWF and inflammation markers was performed among the HFpEF patients. Further, statistical significance of the analysis remained after adjusting variables such as body mass index, low-density lipoprotein cholesterol, total cholesterol, coronary artery disease, and type 2 diabetes mellitus (ß = 0.406, t = 4.579, P < .001; ß = 0.323, t = 3.218, P < .001; ß = 0.581, t = 6.922, P < .001). Our study shows that elevated vWF levels are associated with HFpEF, and it may serve as a potential biomarker for HFpEF severity. We also found that increased vWF levels are positively correlated to IL-6, TNF-α, and CRP, which may provide a clue for further researching the pathogenesis of HFpEF.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Biomarcadores , Proteína C-Reativa/análise , Colesterol , Galectina 3 , Humanos , Inflamação , Interleucina-6 , Óxido Nítrico , Volume Sistólico , Ativador de Plasminogênio Tecidual , Fator de Necrose Tumoral alfa , Fator de von Willebrand/metabolismo
7.
Int J Mol Sci ; 23(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35955419

RESUMO

The vascular endothelium has several important functions, including hemostasis. The homeostasis of hemostasis is based on a fine balance between procoagulant and anticoagulant proteins and between fibrinolytic and antifibrinolytic ones. Coagulopathies are characterized by a mutation-induced alteration of the function of certain coagulation factors or by a disturbed balance between the mechanisms responsible for regulating coagulation. Homeostatic therapies consist in replacement and nonreplacement treatments or in the administration of antifibrinolytic agents. Rebalancing products reestablish hemostasis by inhibiting natural anticoagulant pathways. These agents include monoclonal antibodies, such as concizumab and marstacimab, which target the tissue factor pathway inhibitor; interfering RNA therapies, such as fitusiran, which targets antithrombin III; and protease inhibitors, such as serpinPC, which targets active protein C. In cases of thrombophilia (deficiency of protein C, protein S, or factor V Leiden), treatment may consist in direct oral anticoagulants, replacement therapy (plasma or recombinant ADAMTS13) in cases of a congenital deficiency of ADAMTS13, or immunomodulators (prednisone) if the thrombophilia is autoimmune. Monoclonal-antibody-based anti-vWF immunotherapy (caplacizumab) is used in the context of severe thrombophilia, regardless of the cause of the disorder. In cases of disseminated intravascular coagulation, the treatment of choice consists in administration of antifibrinolytics, all-trans-retinoic acid, and recombinant soluble human thrombomodulin.


Assuntos
Fator V/metabolismo , Trombofilia , Fator de von Willebrand , Anticoagulantes , Endotélio Vascular/metabolismo , Fator VIII/genética , Fator VIII/uso terapêutico , Homeostase , Humanos , Proteína C/uso terapêutico , Trombofilia/genética , Fator de von Willebrand/metabolismo
8.
Medicina (Kaunas) ; 58(8)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36013544

RESUMO

The aim of this review is to highlight all the factors that associate venous thromboembolism (VTE) with aging. Elderly people are characterized by a higher incidence of thrombosis taking into account the co-existing comorbidities, complications and fatality that arise. Based on the Virchow triad, pathophysiological aspects of venous stasis, endothelium injury and hypercoagulability in elderly people (≥65 years) are described in detail. More precisely, venous wall structure, nitric oxide (NO) and endothelin-1 expression are impaired in this age group. Furthermore, an increase in high-molecular-weight kininogen (HMWK), prekallikrein, factors V, VII, VIII, IX and XI, clot lysis time (CLT) and von Willebrand factor (vWF) is observed. Age-dependent platelet dysfunction and changes in anticoagulant factors are also illustrated. A "low-grade inflammation stage" is delineated as a possible risk factor for thrombosis in the elderly. Consequently, clinical implications for frail elderly people related to diagnosis, treatment, bleeding danger and VTE recurrence emerge. We conclude that aging is an acquired thrombotic factor closely related to pathophysiological changes.


Assuntos
Tromboembolia Venosa , Idoso , Envelhecimento , Fator V , Humanos , Fatores de Risco , Tromboembolia Venosa/epidemiologia , Fator de von Willebrand/metabolismo
9.
Br J Biomed Sci ; 79: 10313, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35996503

RESUMO

Introduction: Diabetes is a leading risk factor for cardiovascular disease (CVD), the pathophysiology of both being linked to metabolic, endothelial, renal, angiogenic and platelet abnormalities. We hypothesised that abnormalities in these systems are more adverse in those whose CVD is compounded by diabetes, compared to those with diabetes or CVD alone. Materials and methods: Serum or plasma from 66 patients with diabetes alone, 76 with CVD alone, and 70 with both diabetes and CVD i.e. diabetic cardiovascular disease, was probed for markers of angiogenesis [angiopoietin 1 and 2, vascular endothelial growth factor (VEGF) and endoglin], metabolic [soluble receptor for advanced glycation products (sRAGE), leptin, lipocalin-2, interleukin-8, and cystatin-C], the endothelium (von Willebrand factor, endothelial microparticles and soluble E selectin)], and the platelet (platelet microparticles and soluble P selectin) by ELISA, Luminex or flow cytometry. Results: VEGF (p = 0.04), von Willebrand factor (p = 0.001) and endothelial microparticles (p = 0.042) were all higher in diabetic cardiovascular disease than in diabetes alone and cardiovascular disease alone. Soluble E selectin was higher in diabetic cardiovascular disease than in diabetes alone (p = 0.045), whilst cystatin-C (p = 0.004) and soluble P selectin (p < 0.001) were higher in diabetes and diabetic cardiovascular disease than in cardiovascular disease alone. There were no differences in angiopoietin 1 or 2, endoglin, sRAGE, leptin, lipocalin-2, or interleukin-8. Conclusion: Angiopoietin 1 or 2, endoglin, sRAGE, leptin, lipocalin-2, interleukin-8, and cystatin-c cannot differentiate diabetes from cardiovascular disease, or both conditions combined. Our data point to a more adverse endothelial (von Willebrand factor, endothelial microparticles), and angiogenic profile (VEGF) in those with diabetic cardiovascular disease, supporting the view that this group should be targeted more aggressively.


Assuntos
Doenças Cardiovasculares , Cistatinas , Diabetes Mellitus , Angiopoietina-1/metabolismo , Biomarcadores , Cistatinas/metabolismo , Selectina E/metabolismo , Endoglina/metabolismo , Endotélio/química , Endotélio/metabolismo , Humanos , Interleucina-8 , Leptina , Lipocalina-2 , Selectina-P/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fator de von Willebrand/análise , Fator de von Willebrand/metabolismo
10.
Pharmacol Res ; 183: 106413, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36007773

RESUMO

Platelets play a key role in normal hemostasis, whereas pathological platelet adhesion is involved in various cardiovascular events. The underlying cause in cardiovascular events involves plaque rupture leading to subsequent platelet adhesion, activation, release, and eventual thrombosis. Traditional antithrombotic drugs often target the signal transduction process of platelet adhesion receptors by influencing the synthesis of some key molecules, and their effects are limited. Posttranslational modifications (PTMs) of platelet adhesion receptors increase the functional diversity of the receptors and affect platelet physiological and pathological processes. Antithrombotic drugs targeting PTMs of platelet adhesion receptors may represent a new therapeutic idea. In this review, various PTMs, including phosphorylation, glycosylation, ubiquitination, nitrosylation, methylation, lipidation, and proteolysis, of three platelet adhesion receptors, glycoprotein Ib-IX-V (GPIb-IX-V), glycoprotein VI (GPVI), and integrin αIIbß3, are reviewed. It is important to comprehensively understand the PTMs process of platelet adhesion receptors.


Assuntos
Complexo Glicoproteico GPIb-IX de Plaquetas , Trombose , Plaquetas , Fibrinolíticos/farmacologia , Humanos , Ativação Plaquetária , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Complexo Glicoproteico GPIb-IX de Plaquetas/farmacologia , Processamento de Proteína Pós-Traducional , Fator de von Willebrand/metabolismo , Fator de von Willebrand/farmacologia
11.
J Am Heart Assoc ; 11(16): e024581, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35929448

RESUMO

Background Arteriovenous fistula (AVF) maturation failure is a main limitation of vascular access. Maturation is determined by the intricate balance between outward remodeling and intimal hyperplasia, whereby endothelial cell dysfunction, platelet aggregation, and vascular smooth muscle cell (VSMC) proliferation play a crucial role. von Willebrand Factor (vWF) is an endothelial cell-derived protein involved in platelet aggregation and VSMC proliferation. We investigated AVF vascular remodeling in vWF-deficient mice and vWF expression in failed and matured human AVFs. Methods and Results Jugular-carotid AVFs were created in wild-type and vWF-/- mice. AVF flow was determined longitudinally using ultrasonography, whereupon AVFs were harvested 14 days after surgery. VSMCs were isolated from vena cavae to study the effect of vWF on VSMC proliferation. Patient-matched samples of the basilic vein were obtained before brachio-basilic AVF construction and during superficialization or salvage procedure 6 weeks after AVF creation. vWF deficiency reduced VSMC proliferation and macrophage infiltration in the intimal hyperplasia. vWF-/- mice showed reduced outward remodeling (1.5-fold, P=0.002) and intimal hyperplasia (10.2-fold, P<0.0001). AVF flow in wild-type mice was incremental over 2 weeks, whereas flow in vWF-/- mice did not increase, resulting in a two-fold lower flow at 14 days compared with wild-type mice (P=0.016). Outward remodeling in matured patient AVFs coincided with increased local vWF expression in the media of the venous outflow tract. Absence of vWF in the intimal layer correlated with an increase in the intima-media ratio. Conclusions vWF enhances AVF maturation because its positive effect on outward remodeling outweighs its stimulating effect on intimal hyperplasia.


Assuntos
Fístula Arteriovenosa , Derivação Arteriovenosa Cirúrgica , Miócitos de Músculo Liso , Fator de von Willebrand , Animais , Derivação Arteriovenosa Cirúrgica/métodos , Proliferação de Células , Humanos , Hiperplasia , Camundongos , Camundongos Knockout , Miócitos de Músculo Liso/citologia , Fator de von Willebrand/metabolismo
12.
J Thromb Thrombolysis ; 54(2): 211-216, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35881214

RESUMO

The COVID-19 pandemic is often accompanied by severe respiratory illness and thrombotic complications. Von Willebrand Factor (VWF) levels are highly elevated in this condition. However, limited data are available on the qualitative activity of VWF in COVID-19. We measured plasma VWF levels quantitatively (VWF antigen) and qualitatively (ristocetin-induced platelet agglutination, glycoprotein IbM (GPIbM) binding, and collagen binding). Consistent with prior reports, VWF antigen levels were significantly elevated in hospitalized patients with or without COVID-19. The GPIbM and collagen binding activity-to-antigen ratios were significantly reduced, consistent with qualitative changes in VWF in COVID-19. Of note, critically ill hospitalized patients without COVID-19 had similar reductions in VWF activity-to-antigen ratios as patients with COVID-19. Our data suggest that qualitative changes in VWF in COVID-19 may not be specific to COVID-19. Future studies are warranted to determine the mechanisms responsible for qualitative changes in VWF in COVID-19 and other critical illnesses.• VWF levels were increased in COVID-19 compared to healthy controls.• VWF activity-to-antigen ratios were decreased in COVID-19 compared to healthy controls.• There were no differences in VWF activity-to-antigen ratios between hospitalized patients with or without COVID-19.• These findings are consistent with qualitative changes in VWF in systemic inflammation which are not specific to COVID-19.• Future studies are needed to define possible roles of changes in conformation or multimer length in the qualitative changes in VWF in systemic inflammation.


Assuntos
COVID-19 , Doenças de von Willebrand , Colágeno , Humanos , Inflamação , Pandemias , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Fator de von Willebrand/metabolismo
13.
PLoS One ; 17(7): e0271527, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35839244

RESUMO

Decreased platelet count is an early phenomenon in asexual Plasmodium falciparum parasitemia, but its association with acute or long-term functional changes in platelets and coagulation is unknown. Moreover, the impact of gametocytemia on platelets and coagulation remains unclear. We investigated the changes in platelet number and function during early asexual parasitemia, gametocytemia and convalescence in 16 individuals participating in a controlled human malaria infection study, and studied its relationship with changes in total and active von Willebrand factor levels (VWF) and the coagulation system. Platelet activation and reactivity were determined by flow cytometry, and the coagulation system was assessed using different representative assays including antigen assays, activity assays and global functional assays. Platelet count was decreased during asexual blood stage infection but normalized during gametocytemia. Platelet P-selectin expression was slightly increased during asexual parasitemia, gametocytemia and at day 64. In contrast, platelet reactivity to different agonists remained unchanged, except a marked decrease in reactivity to low dose collagen-related peptide-XL. Thrombin generation and antigen assays did not show a clear activation of the coagulation during asexual parasitemia, whereas total and active VWF levels were markedly increased. During gametocytemia and on day 64, the endogenous thrombin potential, thrombin peak and velocity index were increased and prothrombin conversion and plasma prothrombin levels were decreased. We conclude that the decreased platelet count during asexual parasitemia is associated with increased active VWF levels (i.e. endothelial activation), but not platelet hyperreactivity or hypercoagulability, and that the increased platelet clearance in asexual parasitemia could cause spontaneous VWF-platelet complexes formation.


Assuntos
Malária , Parasitemia , Plaquetas/metabolismo , Hemostasia , Humanos , Malária/metabolismo , Parasitemia/metabolismo , Protrombina/metabolismo , Trombina/metabolismo , Fator de von Willebrand/metabolismo
14.
Blood Adv ; 6(13): 3979-3990, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35816358

RESUMO

The presence of blood flow influences the interaction between von Willebrand factor (VWF) and blood cells, affecting characteristics of forming blood clots. The interactions between coagulation and inflammation have mainly been studied in thrombosis models, but it remains unclear whether these interactions might also play a role in reduced bleeding in patients with bleeding disorders. In this systematic review, we provide an overview of the literature investigating the interactions between VWF and blood cells in flow models. For article selection, a systematic search was performed in Embase, Medline-Ovid, Cochrane Library, Web of Science databases, and Google Scholar. After selection, 24 articles were included. These articles describe direct or platelet-dependent interactions between VWF and neutrophils, monocytes, erythrocytes, or lymphocytes under different flow conditions. Almost all the described interactions required the presence of activated platelets. Only erythrocytes, monocytes, and natural killer cells were capable of directly binding the VWF multimers. Overall, interactions between VWF and blood cells mainly occurred in the presence of platelets. Because of the large variation in study design and used flow rates, further research is necessary to compare the results between studies and draw firm conclusions on when and under what conditions these interactions can occur. After our findings, many questions remained unanswered. This review might provide a starting point for future research. Extended knowledge on the influence of blood flow on VWF and blood cell interactions can contribute to improved understanding of the variation in bleeding in patients with bleeding disorders.


Assuntos
Trombose , Fator de von Willebrand , Testes de Coagulação Sanguínea , Plaquetas/metabolismo , Hemorragia/etiologia , Humanos , Trombose/etiologia , Fator de von Willebrand/metabolismo
15.
Arterioscler Thromb Vasc Biol ; 42(9): 1103-1112, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35861953

RESUMO

The activating interplay of thrombosis and inflammation (thromboinflammation) has been established as a major underlying pathway, driving not only cardiovascular disease but also autoimmune disease and most recently, COVID-19. Throughout the years, innate immune cells have emerged as important modulators of this process. As the most abundant white blood cell in humans, neutrophils are well-positioned to propel thromboinflammation. This includes their ability to trigger an organized cell death pathway with the release of decondensed chromatin structures called neutrophil extracellular traps. Decorated with histones and cytoplasmic and granular proteins, neutrophil extracellular traps exert cytotoxic, immunogenic, and prothrombotic effects accelerating disease progression. Distinct steps leading to extracellular DNA release (NETosis) require the activities of PAD4 (protein arginine deiminase 4) catalyzing citrullination of histones and are supported by neutrophil inflammasome. By linking the immunologic function of neutrophils with the procoagulant and proinflammatory activities of monocytes and platelets, PAD4 activity holds important implications for understanding the processes that fuel thromboinflammation. We will also discuss mechanisms whereby vascular occlusion in thromboinflammation depends on the interaction of neutrophil extracellular traps with ultra-large VWF (von Willebrand Factor) and speculate on the importance of PAD4 in neutrophil inflammasome assembly and neutrophil extracellular traps in thromboinflammatory diseases including atherosclerosis and COVID-19.


Assuntos
Aterosclerose , COVID-19 , Armadilhas Extracelulares , Trombose , Aterosclerose/metabolismo , Armadilhas Extracelulares/metabolismo , Histonas/metabolismo , Humanos , Inflamassomos/metabolismo , Inflamação/metabolismo , Neutrófilos/metabolismo , Tromboinflamação , Trombose/etiologia , Trombose/metabolismo , Fator de von Willebrand/metabolismo
16.
Blood Adv ; 6(17): 5100-5112, 2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-35839075

RESUMO

Transcription factor RUNX1 is a master regulator of hematopoiesis and megakaryopoiesis. RUNX1 haplodeficiency (RHD) is associated with thrombocytopenia and platelet granule deficiencies and dysfunction. Platelet profiling of our study patient with RHD showed decreased expression of RAB31, a small GTPase whose cell biology in megakaryocytes (MKs)/platelets is unknown. Platelet RAB31 messenger RNA was decreased in the index patient and in 2 additional patients with RHD. Promoter-reporter studies using phorbol 12-myristate 13-acetate-treated megakaryocytic human erythroleukemia cells revealed that RUNX1 regulates RAB31 via binding to its promoter. We investigated RUNX1 and RAB31 roles in endosomal dynamics using immunofluorescence staining for markers of early endosomes (EEs; early endosomal autoantigen 1) and late endosomes (CD63)/multivesicular bodies. Downregulation of RUNX1 or RAB31 (by small interfering RNA or CRISPR/Cas9) showed a striking enlargement of EEs, partially reversed by RAB31 reconstitution. This EE defect was observed in MKs differentiated from a patient-derived induced pluripotent stem cell line (RHD-iMKs). Studies using immunofluorescence staining showed that trafficking of 3 proteins with distinct roles (von Willebrand factor [VWF], a protein trafficked to α-granules; epidermal growth factor receptor; and mannose-6-phosphate) was impaired at the level of EE on downregulation of RAB31 or RUNX1. There was loss of plasma membrane VWF in RUNX1- and RAB31-deficient megakaryocytic human erythroleukemia cells and RHD-iMKs. These studies provide evidence that RAB31 is downregulated in RHD and regulates megakaryocytic vesicle trafficking of 3 major proteins with diverse biological roles. EE defect and impaired vesicle trafficking is a potential mechanism for the α-granule defects observed in RUNX1 deficiency.


Assuntos
Leucemia Eritroblástica Aguda , Megacariócitos , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Receptores ErbB/metabolismo , Humanos , Megacariócitos/metabolismo , Proteínas rab de Ligação ao GTP/genética , Proteínas rab de Ligação ao GTP/metabolismo , Fator de von Willebrand/metabolismo
17.
Tissue Eng Regen Med ; 19(5): 1051-1061, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35852724

RESUMO

BACKGROUND: Angiogenesis plays an important role in determining the fat graft survival. However, clinical preconditioning techniques that target angiogenesis during fat grafting have not been established so far. Adenosine has emerged as a regulator of angiogenesis under hypoxic conditions; therefore, the aim of this study was to investigate the effects and underlying mechanisms of adenosine prefabrication on fat graft survival. METHODS: In the first animal study, a total of 32 mice were transplanted with fat prefabricated with vehicle (Control, N = 16) or adenosine (Adenosine, N = 16). In the second animal study, 24 mice were divided into three groups based on the type of fat graft: Control (N = 8), Adenosine (N = 8), and Axitinib (cotreatment of adenosine with axitinib, N = 8). At 1- and 4-weeks post-transplantation, grafts were evaluated by histopathological and biochemical assessment. Adenosine-induced vascular endothelial growth factor (VEGF) production and angiogenesis were determined using cell cultures. RESULTS: The retention volumes of fat grafts in the adenosine group were significantly increased until 4 weeks. Fat grafts from the adenosine group exhibited greater structural integrity, reduced fibrosis, and increased blood vessels. The expression levels of angiogenesis-related genes, Vegfa, Vegfr1, Vegfr2, and Vwf, were elevated in the adenosine group. Furthermore, adenosine upregulated VEGF production in preadipocytes, thereby enhancing the migration of endothelial cells. Treatment with the axitinib, VEGF receptor inhibitor, abrogated the adenosine-induced angiogenesis in the fat grafts. CONCLUSION: Adenosine prefabrication in fat improved the graft survival by enhancing angiogenesis through the VEGF/VEGFR axis in the preadipocytes and endothelial cells. Therefore, this method may be used as a novel strategy to increase the retention rate in fat grafts.


Assuntos
Sobrevivência de Enxerto , Fator A de Crescimento do Endotélio Vascular , Adenosina/metabolismo , Adenosina/farmacologia , Tecido Adiposo/metabolismo , Animais , Axitinibe/farmacologia , Células Endoteliais/metabolismo , Camundongos , Receptores de Fatores de Crescimento do Endotélio Vascular/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/metabolismo , Fatores de Crescimento do Endotélio Vascular/farmacologia , Fator de von Willebrand/metabolismo , Fator de von Willebrand/farmacologia
18.
Phys Chem Chem Phys ; 24(24): 14857-14865, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35698887

RESUMO

von Willebrand factor (VWF) senses and responds to the hemodynamic forces to interact with the circulatory system and platelets in hemostasis and thrombosis. The dark side of this mechanobiology is implicated in atherothrombosis, stroke, and, more recently, the COVID-19 thrombotic symptoms. The force-responsive element controlling VWF activation predominantly resides in the N terminal auto-inhibitory module (N-AIM) flanking its A1 domain. Nevertheless, the detailed mechano-chemistry of soluble VWF N-AIM is poorly understood at the sub-molecular level as it is assumed to be unstructured loops. Using the free molecular dynamics (MD) simulations, we first predicted a hairpin-like structure of the soluble A1 N-AIM derived polypeptide (Lp; sequences Q1238-E1260). Then we combined molecular docking and steered molecular dynamics (SMD) simulations to examine how Lp regulates the A1-GPIbα interaction under tensile forces. Our simulation results indicate that Lp suppresses the catch bond in a sandwich complex of A1-Lp-GPIbα yet contributes an additional catch-bond residue D1249. To experimentally benchmark the binding kinetics for A1-GPIbα in the absence or presence of Lp, we conducted the force spectroscopy-biomembrane force probe (BFP) assays. We found similar suppression on the A1-GPIbα catch bond with soluble Lp in presence. Clinically, as more and more therapeutic candidates targeting the A1-GPIbα axis have entered clinical trials to treat patients with TTP and acute coronary syndrome, our work represents an endeavor further towards an effective anti-thrombotic approach without severe bleeding side effects as most existing drugs suffer.


Assuntos
COVID-19 , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Fator de von Willebrand , Plaquetas , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Fator de von Willebrand/química , Fator de von Willebrand/metabolismo
19.
Cell Mol Life Sci ; 79(6): 344, 2022 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-35660980

RESUMO

Weibel-Palade bodies (WPB) are elongated, rod-like secretory organelles unique to endothelial cells that store the pro-coagulant von-Willebrand factor (VWF) and undergo regulated exocytosis upon stimulation with Ca2+- or cAMP-raising agonists. We show here that WPB preferentially initiate fusion with the plasma membrane at their tips and identify synaptotagmin-like protein 2-a (Slp2-a) as a positive regulator of VWF secretion most likely mediating this topological selectivity. Following secretagogue stimulation, Slp2-a accumulates at one WPB tip before fusion occurs at this site. Depletion of Slp2-a reduces Ca2+-dependent secretion of highly multimeric VWF and interferes with the formation of actin rings at WPB-plasma membrane fusion sites that support the expulsion of the VWF multimers and most likely require a tip-end fusion topology. Phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] binding via the C2A domain of Slp2-a is required for accumulation of Slp2-a at the tip ends of fusing WPB, suggesting that Slp2-a mediates polar exocytosis by initiating contacts between WPB tips and plasma membrane PI(4,5)P2.


Assuntos
Corpos de Weibel-Palade , Fator de von Willebrand , Células Cultivadas , Exocitose/fisiologia , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Corpos de Weibel-Palade/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
20.
Mol Biol Evol ; 39(7)2022 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-35723968

RESUMO

Opossums in the tribe Didelphini are resistant to pit viper venoms and are hypothesized to be coevolving with venomous snakes. Specifically, a protein involved in blood clotting (von Willebrand factor [vWF] which is targeted by snake venom C-type lectins [CTLs]) has been found to undergo rapid adaptive evolution in Didelphini. Several unique amino acid changes in vWF could explain their resistance; however, experimental evidence that these changes disrupt binding to venom CTLs was lacking. Furthermore, without explicit testing of ancestral phenotypes to reveal the mode of evolution, the assertion that this system represents an example of coevolution rather than noncoevolutionary adaptation remains unsupported. Using expressed vWF proteins and purified venom CTLs, we quantified binding affinity for vWF proteins from all resistant taxa, their venom-sensitive relatives, and their ancestors. We show that CTL-resistant vWF is present in opossums outside clade Didelphini and likely across a wider swath of opossums (family Didelphidae) than previously thought. Ancestral reconstruction and in vitro testing of vWF phenotypes in a clade of rapidly evolving opossums reveal a pattern consistent with trench warfare coevolution between opossums and their venomous snake prey.


Assuntos
Venenos de Crotalídeos , Crotalinae , Animais , Venenos de Crotalídeos/genética , Gambás/metabolismo , Venenos de Serpentes/metabolismo , Serpentes/metabolismo , Fator de von Willebrand/genética , Fator de von Willebrand/metabolismo
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