Removal of endothelial surface-associated von villebrand factor suppresses accelerate datherosclerosis after myocardial infarction.

BACKGROUND: Thromboinflammation involving platelet adhesion to endothelial surface-associated von Willebrand factor (VWF) has been implicated in the accelerated progression of non-culprit plaques after MI. The aim of this study was to use arterial endothelial molecular imaging to mechanistically evaluate endothelial-associated VWF as a therapeutic target for reducing remote plaque activation after myocardial infarction (MI). METHODS: Hyperlipidemic mice deficient for the low-density lipoprotein receptor and Apobec-1 underwent closed-chest MI and were treated chronically with either: (i) recombinant ADAMTS13 which is responsible for proteolytic removal of VWF from the endothelial surface, (ii) N-acetylcysteine (NAC) which removes VWF by disulfide bond reduction, (iii) function-blocking anti-factor XI (FXI) antibody, or (iv) no therapy. Non-ischemic controls were also studied. At day 3 and 21, ultrasound molecular imaging was performed with probes targeted to endothelial-associated VWF A1-domain, platelet GPIbα, P-selectin and vascular cell adhesion molecule-1 (VCAM-1) at lesion-prone sites of the aorta. Histology was performed at day 21. RESULTS: Aortic signal for P-selectin, VCAM-1, VWF, and platelet-GPIbα were all increased several-fold (p < 0.01) in post-MI mice versus sham-treated animals at day 3 and 21. Treatment with NAC and ADAMTS13 significantly attenuated the post-MI increase for all four molecular targets by > 50% (p < 0.05 vs. non-treated at day 3 and 21). On aortic root histology, mice undergoing MI versus controls had 2-4 fold greater plaque size and macrophage content (p < 0.05), approximately 20-fold greater platelet adhesion (p < 0.05), and increased staining for markers of platelet transforming growth factor-ß1 signaling. Accelerated plaque growth and inflammatory activation was almost entirely prevented by ADAMTS13 and NAC. Inhibition of FXI had no significant effect on molecular imaging signal or plaque morphology. CONCLUSIONS: Plaque inflammatory activation in remote arteries after MI is strongly influenced by VWF-mediated platelet adhesion to the endothelium. These findings support investigation into new secondary preventive therapies for reducing non-culprit artery events after MI.

Twenty-Four week Taichi training improves pulmonary diffusion capacity and glycemic control in patients with Type 2 diabetes mellitus.

This study evaluated the effect of 24-week Taichi training and Taichi plus resistance band training on pulmonary diffusion capacity and glycemic control in patients with Type 2 diabetes mellitus (T2DM). Forty-eight patients with T2DM were randomly divided into three groups: Group A-Taichi training: practiced Taichi 60 min/day, 6 days/week for 24 weeks; Group B-Taichi plus resistance band training: practiced 60-min Taichi 4 days/week plus 60-min resistance band training 2 days/week for 24 weeks; and Group C-controls: maintaining their daily lifestyles. Stepwise multiple regression analysis was applied to predict diffusion capacity of the lungs for carbon monoxide (DLCO) by fasting blood glucose, insulin, glycosylated hemoglobin (HbA1c), tumour necrosis factor alpha (TNF-α), von Willebrand Factor (vWF), interleukin-6 (IL-6), intercellular adhesion molecule 1 (ICAM-1), endothelial nitric oxide synthase (eNOS), nitric oxide (NO), endothelin-1 (ET-1), vascular endothelial growth factor, and prostaglandin I-2. Taichi with or without resistance band training significantly improved DLCO, increased insulin sensitivity, eNOS and NO, and reduced fasting blood glucose, insulin, HbA1c, TNF-α, vWF, IL-6, ICAM-1, and ET-1. There was no change in any of these variables in the control group. DLCO was significantly predicted (R2 = 0.82) by insulin sensitivity (standard-ß = 0.415, P<0.001), eNOS (standard-ß = 0.128, P = 0.017), TNF-α (standard-ß = -0.259, P = 0.001), vWF (standard-ß = -0.201, P = 0.007), and IL-6 (standard-ß = -0.175, P = 0.032) in patients with T2DM. The impact of insulin sensitivity was the most important predictor for the variation of DLCO based on the multiple regression modeling. This study demonstrates that 24-week Taichi training and Taichi plus resistance band training effectively improve pulmonary diffusion capacity and blood glycemic control in patients with T2DM. Variation of DLCO is explained by improved insulin sensitivity and endothelial function, and reduced inflammatory markers, including TNF-α, vWF, and IL-6.

[Mechanism of astragaloside â £ combined with Panax notoginseng saponins in regulating angiogenesis to treat cerebral ischemia based on network pharmacology and experimental verification].

Network pharmacology and animal and cell experiments were employed to explore the mechanism of astragaloside Ⅳ(AST Ⅳ) combined with Panax notoginseng saponins(PNS) in regulating angiogenesis to treat cerebral ischemia. The method of network pharmacology was used to predict the possible mechanisms of AST Ⅳ and PNS in treating cerebral ischemia by mediating angiogenesis. In vivo experiment: SD rats were randomized into sham, model, and AST Ⅳ(10 mg·kg~(-1)) + PNS(25 mg·kg~(-1)) groups, and the model of cerebral ischemia was established with middle cerebral artery occlusion(MCAO) method. AST Ⅳ and PNS were administered by gavage twice a day. the Longa method was employed to measure the neurological deficits. The brain tissue was stained with hematoxylin-eosin(HE) to reveal the pathological damage. Immunohistochemical assay was employed to measure the expression of von Willebrand factor(vWF), and immunofluorescence assay to measure the expression of vascular endothelial growth factor A(VEGFA). Western blot was employed to determine the protein levels of vascular endothelial growth factor receptor 2(VEGFR2), VEGFA, phosphorylated phosphatidylinositol 3-kinase(p-PI3K), and phosphorylated protein kinase B(p-AKT) in the brain tissue. In vitro experiment: the primary generation of rat brain microvascular endothelial cells(rBEMCs) was cultured and identified. The third-generation rBMECs were assigned into control, model, AST Ⅳ(50 µmol·L~(-1)) + PNS(30 µmol·L~(-1)), LY294002(PI3K/AKT signaling pathway inhibitor), 740Y-P(PI3K/AKT signaling pathway agonist), AST Ⅳ + PNS + LY294002, and AST Ⅳ + PNS + 740Y-P groups. Oxygen glucose deprivation/re-oxygenation(OGD/R) was employed to establish the cell model of cerebral ischemia-reperfusion injury. The cell counting kit-8(CCK-8) and scratch assay were employed to examine the survival and migration of rBEMCs, respectively. Matrigel was used to evaluate the tube formation from rBEMCs. The Transwell assay was employed to examine endothelial cell permeability. Western blot was employed to determine the expression of VEGFR2, VEGFA, p-PI3K, and p-AKT in rBEMCs. The results of network pharmacology analysis showed that AST Ⅳ and PNS regulated 21 targets including VEGFA and AKT1 of angiogenesis in cerebral infarction. Most of these 21 targets were involved in the PI3K/AKT signaling pathway. The in vivo experiments showed that compared with the model group, AST Ⅳ + PNS reduced the neurological deficit score(P<0.05) and the cell damage rate in the brain tissue(P<0.05), promoted the expression of vWF and VEGFA(P<0.01) and angiogenesis, and up-regulated the expression of proteins in the PI3K/AKT pathway(P<0.05, P<0.01). The in vitro experiments showed that compared with the model group, the AST Ⅳ + PNS, 740Y-P, AST Ⅳ + PNS + LY294002, and AST Ⅳ + PNS + 740Y-P improved the survival of rBEMCs after OGD/R, enhanced the migration of rBEMCs, increased the tubes formed by rBEMCs, up-regulated the expression of proteins in the PI3K/AKT pathway, and reduced endothelial cell permeability(P<0.05, P<0.01). Compared with the LY294002 group, the AST Ⅳ + PNS + LY294002 group showed increased survival rate, migration rate, and number of tubes, up-regulated expression of proteins in the PI3K/AKT pathway, and decreased endothelial cell permeability(P<0.05,P<0.01). Compared with the AST Ⅳ + PNS and 740Y-P groups, the AST Ⅳ + PNS + 740Y-P group presented increased survival rate, migration rate, and number of tubes and up-regulated expression of proteins in the PI3K/AKT pathway, and reduced endothelial cell permeability(P<0.01). This study indicates that AST Ⅳ and PNS can promote angiogenesis after cerebral ischemia by activating the PI3K/AKT signaling pathway.

Early-onset indicators of a hypercoagulable state and clinical complications in a cohort of children with sickle cell trait.

Adults with sickle cell trait (SCT) have a procoagulant state with increased risk of thromboembolism, but limited data are available for children. We compared the coagulation profile of children with SCT, different sickle cell disease (SCD) genotypes, and healthy controls. Compared to controls and similarly to HbSC patients, 41 SCT children (mean age 6.85 years; 20 males; 88% Africans) had a characteristic procoagulant profile: higher levels of factor VIII, von Willebrand factor (VWF) Ag and CBA, D-dimer; lower levels of ADAMTS 13 activity, ADAMTS13 activity: VWFAg, plasminogen activator inhibitor, tissue plasminogen activator. Moreover, 13/41 had clinical complications of SCD, five requiring hospitalization.

Diagnosis and treatment of von Willebrand disease in 2024 and beyond.

MANUSCRIPT BACKGROUND AND AIM: The diagnosis and clinical care of patients with von Willebrand disease (VWD) has continued to evolve since the characterization of the von Willebrand factor (VWF) gene in 1985. This condition is almost certainly the most common inherited bleeding disorder, and the major symptomatic burden of the disease is experienced by females during their reproductive years. Diagnosis relies on the identification of a personal and family history of excessive mucocutaneous bleeding, and laboratory features consistent with quantitative and/or qualitative abnormalities of VWF. This review focuses on three aspects of VWD management, with current updates and a look into the future. MANUSCRIPT THEMES: First, we will address the role of genetics in the diagnosis and possible therapies for VWD. With current technologies, VWD genetic diagnosis is usually confined to the confirmation of type 2 subtypes of the disease and type 3 VWD analysis for family planning. While type 3 VWD is a potential candidate for the application of gene therapy, no treatments are currently close to entering the clinic. Second, the peri-procedural management of patients with VWD remains an important element of care. The choice of product, its dose and schedule all require careful consideration depending upon the type and disruptive nature of the planned procedure. Lastly, in addition to gene therapy, several other novel therapeutic interventions are also being developed for bleeding and prophylaxis in VWD. These include a VWF aptamer interfering with VWF clearance and bioengineered forms of VWF.

Analyzing and modeling massive transfusion strategies and the role of fibrinogen-How much is the patient actually receiving?

BACKGROUND: Hemorrhage is a leading cause of preventable death in trauma, cardiac surgery, liver transplant, and childbirth. While emphasis on protocolization and ratio of blood product transfusion improves ability to treat hemorrhage rapidly, tools to facilitate understanding of the overall content of a specific transfusion strategy are lacking. Medical modeling can provide insights into where deficits in treatment could arise and key areas for clinical study. By using a transfusion model to gain insight into the aggregate content of massive transfusion protocols (MTPs), clinicians can optimize protocols and create opportunities for future studies of precision transfusion medicine in hemorrhage treatment. METHODS: The transfusion model describes the individual round and aggregate content provided by four rounds of MTP, illustrating that the total content of blood elements and coagulation factor changes over time, independent of the patient's condition. The configurable model calculates the aggregate hematocrit, platelet concentration, percent volume plasma, total grams and concentration of citrate, percent volume anticoagulant and additive solution, and concentration of clotting factors: fibrinogen, factor XIII, factor VIII, and von Willebrand factor, provided by the MTP strategy. RESULTS: Transfusion strategies based on a 1:1:1 or whole blood foundation provide between 13.7 and 17.2 L of blood products over four rounds. Content of strategies varies widely across all measurements based on base strategy and addition of concentrated sources of fibrinogen and other key clotting factors. DISCUSSION: Differences observed between modeled transfusion strategies provide key insights into potential opportunities to provide patients with precision transfusion strategy.

Novel serum protein biomarker panel for early diagnosis of pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers. Late presentation of disease at the time of diagnosis is one of the major reasons for dismal prognostic outcomes for PDAC patients. Currently, there is a lack of clinical biomarkers, which can be used to diagnose PDAC patients at an early resectable stage. This study performed proteomic mass spectrometry to identify novel blood-based biomarkers for early diagnosis of PDAC. Serum specimens from 88 PDAC patients and 88 healthy controls (60 discovery cohort and 28 validation cohort) were analyzed using data independent acquisition high resolution mass spectrometry to identify candidate biomarker proteins. A total of 249 proteins were identified and quantified by the mass spectrometric analysis. Six proteins were markedly (>1.5 fold) and significantly (p < .05; q < 0.1) increased in PDAC patients compared to healthy controls in discovery cohort. Notably, four of these six proteins were significantly upregulated in an independent validation cohort. The top three upregulated proteins (i.e., Polymeric Immunoglobulin Receptor [PIGR], von Willebrand Factor [vWF], and Fibrinogen) were validated using enzyme linked immunosorbent assay, which led to selection of PIGR and vWF as a diagnostic biomarker panel for PDAC. The panel showed high ability to diagnose early stage (stage I and II) PDAC patients (area under the curve [AUC]: 0.8926), which was further improved after the addition of clinically used prognostic biomarker (Ca 19-9) to the panel (AUC: 0.9798). In conclusion, a novel serum protein biomarker panel for early diagnosis of PDAC was identified.

Inhibition of platelet adhesion to exposed subendothelial collagen by steric hindrance with blocking peptide nanoparticles.

The inhibition of platelet adhesion to collagen in exposed vessels represents an innovative approach to the treatment of atherosclerosis and thrombosis. This study aimed to engineer peptide-based nanoparticles that prevent platelet binding to subendothelial collagen by engaging with collagen with high affinity. We examined the interactions between integrin α2/ glycoprotein VI/ von Willebrand factor A3 domain and collagen, as well as between the synthesized peptide nanoparticles and collagen, utilizing molecular dynamics simulations and empirical assays. Our findings indicated that the bond between von Willebrand factor and collagen was more robust. Specifically, the sequences SITTIDV, VDVMQRE, and YLTSEMH in von Willebrand factor were identified as essential for its attachment to collagen. Based on these sequences, three peptide nanoparticles were synthesized (BPa: Capric-GNNQQNYK-SITTIDV, BPb: Capric-GNNQQNYK-VDVMQRE, BPc: Capric-GNNQQNYK-YLTSEMH), each displaying significant affinity towards collagen. Of these, the BPa nanoparticles exhibited the most potent interaction with collagen, leading to a 75% reduction in platelet adhesion.

Vascular study of decellularized porcine long bones: Characterization of a tissue engineering model.

INTRODUCTION: Massive bone allografts enable the reconstruction of critical bone defects in numerous conditions (e.g. tumoral, infection or trauma). Unfortunately, their biological integration remains insufficient and the reconstruction may suffer from several postoperative complications. Perfusion-decellularization emerges as a tissue engineering potential solution to enhance osseointegration. Therefore, an intrinsic vascular study of this novel tissue engineering tool becomes essential to understand its efficacy and applicability. MATERIAL AND METHODS: 32 porcine long bones (humeri and femurs) were used to assess the quality of their vascular network prior and after undergoing a perfusion-decellularization protocol. 12 paired bones were used to assess the vascular matrix prior (N = 6) and after our protocol (N = 6) by immunohistochemistry. Collagen IV, Von Willebrand factor and CD31 were targeted then quantified. The medullary macroscopic vascular network was evaluated with 12 bones: 6 were decellularized and the other 6 were, as control, not treated. All 12 underwent a contrast-agent injection through the nutrient artery prior an angio CT-scan acquisition. The images were processed and the length of medullary vessels filled with contrast agent were measured on angiographic cT images obtained in control and decellularized bones by 4 independent observers to evaluate the vascular network preservation. The microscopic cortical vascular network was evaluated on 8 bones: 4 control and 4 decellularized. After injection of gelatinous fluorochrome mixture (calcein green), non-decalcified fluoroscopic microscopy was performed in order to assess the perfusion quality of cortical vascular lacunae. RESULTS: The continuity of the microscopic vascular network was assessed with Collagen IV immunohistochemistry (p-value = 0.805) while the decellularization quality was observed through CD31 and Von Willebrand factor immunohistochemistry (p-values <0.001). The macroscopic vascular network was severely impaired after perfusion-decellularization; nutrient arteries were still patent but the amount of medullary vascular channels measured was significantly higher in the control group compared to the decellularized group (p-value <0.001). On average, the observers show good agreement on these results, except in the decellularized group where more inter-observer discrepancies were observed. The microscopic vascular network was observed with green fluoroscopic signal in almost every canals and lacunae of the bone cortices, in three different bone locations (proximal metaphysis, diaphysis and distal metaphysis). CONCLUSION: Despite the aggressiveness of the decellularization protocol on medullary vessels, total porcine long bones decellularized by perfusion retain an acellular cortical microvascular network. By injection through the intact nutrient arteries, this latter vascular network can still be used as a total bone infusion access for bone tissue engineering in order to enhance massive bone allografts prior implantation.

Perioperative Treatment with Rivaroxaban and Dabigatran on Changes of Coagulation and Platelet Activation Biomarkers following Left Atrial Appendage Closure.

Insufficient data exist regarding the investigation of the impact of novel oral anticoagulants (NOACs) on coagulation activation biomarkers in the context of left atrial appendage closure (LAAC) and device-related thrombosis (DRT). The study was designed to investigate the changes and presence of coagulation activation biomarkers between different antithrombotic strategies following LAAC. A total of 120 nonvalvular atrial fibrillation patients intolerant of long-term anticoagulants, who underwent successful WATCHMAN closure implantation, were enrolled (rivaroxaban, n = 82; dabigatran, n = 38). Blood samples were obtained from left atrium (LA) and left atrial appendage (LAA) during the operation and fasting blood samples on the same day of LAAC and 45 days after discharge. The biochemical indicators, thrombin-antithrombin complex (TAT), soluble P-selectin (sP-selectin), von Willebrand factor (vWF), and CD40 ligand (CD40L), were measured by enzyme-linked immunosorbent assay. The primary endpoints of this study were the efficacy and safety characteristics of different antithrombotic strategies, including DRT incidence, stroke or transient ischemic attack, systemic embolism, and clinical major and nonmajor bleeding complications during the follow-up of 180 days. The results revealed that TAT, vWF, sP-selectin, and CD40L levels in vein were significantly reduced by 2.4% (p = 0.043), 5.0% (p < 0.001), 8.7% (p < 0.001), and 2.5% (p = 0.043) from their baseline levels after rivaroxaban treatment. Conversely, no significant changes were detected in the dabigatran group. Furthermore, the plasma levels of platelet activation biomarkers (CD40L and sP-selectin) in both LA and LAA groups were significantly lower after anticoagulation with rivaroxaban, as compared to dabigatran treatment (CD40L: 554.62 ± 155.54 vs. 445.02 ± 130.04 for LA p = 0.0013, 578.51 ± 156.28 vs. 480.13 ± 164.37 for LAA p = 0.0052; sP-selectin: 2849.07 ± 846.69 vs. 2225.54 ± 799.96 for LA p = 0.0105, 2915.52 ± 1402.40 vs. 2203.41 ± 1061.67 for LAA p = 0.0022). Notably, the present study suggests that rivaroxaban may be more effective in the prevention of DRT for patients undergoing LAAC.

Overexpression of ETV2 in BMSCs promoted wound healing in cutaneous wound mice by triggering the differentiation of BMSCs into endothelial cells and modulating the transformation of M1 phenotype macrophages to M2 phenotype macrophages.

This study aimed to investigate the effects of E26-transformation-specific variant-2 (ETV2) overexpression on wound healing in a cutaneous wound (CW) model and clarify associated mechanisms. pLVX-ETV2 lentivirus expressing ETV2 was constructed and infected into BMSCs to generate ETV2-overexpressed BMSCs (BMSCs+pLVX+ETV2). The RT-PCR assay was applied to amplify ETV2, VE-cadherin, vWF, ARG-1, IL-6, iNOS, TGF-ß, IL-10, TNF-α. Western blot was used to determine expression of VE-cadherin and vWF. ETV2 induced differentiation of BMSCs into ECs by increasing CDH5/CD31, triggering tube-like structures, inducing Dil-Ac-LDL positive BMSCs. ETV2 overexpression increased the gene transcription and expression of VE-cadherin and vWF (P<0.01). Transcription of M1 phenotype specific iNOS gene was lower and transcription of M2 phenotype specific ARG-1 gene was higher in the RAW264.7+BMSCs+ETV2 group compared to the RAW264.7+BMSCs+pLVX group (P<0.01). ETV2 overexpression (RAW264.7+BMSCs+ETV2) downregulated IL-6 and TNF-α, and upregulated IL-10 and TGF-ß gene transcription compared to RAW264.7+BMSCs+pLVX group (P<0.01). ETV2-overexpressed BMSCs promoted wound healing in CW mice and triggered the migration of BMSCs to the wound region and macrophage activation. ETV2-overexpressed BMSCs promoted collagen fibers and blood vessel formation in the wound region of CW mice. In conclusion, this study revealed a novel biofunction of ETV2 molecule in the wound healing process. ETV2 overexpression in BMSCs promoted wound healing in CW mice by triggering BMSCs differentiation into endothelial cells and modulating the transformation of M1 pro-inflammatory and M2 anti-inflammatory macrophages in vitro and in vivo.

ADAMTS-13: A Prognostic Biomarker for Portal Vein Thrombosis in Japanese Patients with Liver Cirrhosis.

Portal vein thrombosis (PVT), one of the most prevalent hepatic vascular conditions in patients with liver cirrhosis (LC), is associated with high mortality rates. An imbalance between a disintegrin-like metalloproteinase with thrombospondin type-1 motifs 13 (ADAMTS-13) enzyme and von Willebrand factor (VWF) is responsible for hypercoagulability, including spontaneous thrombus formation in blood vessels. Herein, we aimed to identify potential prognostic and diagnostic biomarkers in Japanese patients with LC and PVT. In total, 345 patients were divided into two groups: 40 patients who developed PVT (PVT group) and 305 who did not develop PVT (NPVT group). Among the 345 patients with LC, 81% (279/345) were deemed ineligible due to the presence of preventive comorbidities, active or recent malignancies, and organ dysfunction. The remaining 66 patients were divided into two groups: the PVT group (n = 33) and the NPVT group (n = 33). Plasma ADAMTS-13 activity (ADAMTS-13:AC) and the vWF antigen (VWF:Ag) were measured using enzyme-linked immunosorbent assays. Contrast-enhanced, three-dimensional helical computed tomography (CT) was used to detect and characterize PVT. ADAMTS-13:AC was significantly lower in the PVT group than in the NPVT group. No significant differences in plasma vWF:Ag or liver stiffness were observed between the two groups. ADAMTS-13:AC of <18.8 was an independent risk factor for PVT on multivariate analyses (odds ratio: 1.67, 95% confidence interval: 1.21-3.00, p < 0.002). The receiver operating characteristic analysis of ADAMTS-13:AC revealed an area under the curve of 0.913 in PVT detection. Patients with PVT having ADAMTS-13:AC ≥18.8 (n = 17) had higher albumin levels and better prognoses than those with ADAMTS-13:AC <18.8 (n = 16). No significant correlations of ADAMTS-13:AC levels with either fibrin degradation product or D-dimer levels were observed. ADAMTS-13:AC levels could be potential diagnostic and prognostic biomarkers for PVT in Japanese patients with LC.

High thrombin-activatable fibrinolysis inhibitor expression in thrombi from stroke patients in elevated estrogen states.

BACKGROUND: The risk of acute ischemic stroke (AIS) associated with high estrogen states, including pregnant patients and those using oral contraceptives, has been well documented. We described the histological composition of thrombi collected in these cases. METHODS: From a prospective tissue registry (STRIP registry) of thrombi retrieved during mechanical thrombectomy for AIS, we identified 5 patients with high estrogen states: 1 post-partum patient, 1 undergoing hormone replacement therapy and 3 consuming oral contraceptive pills. Five male control patients were randomly chosen matched by age. Immunohistochemistry for CD42b (platelets), von Willebrand factor (vWF), thrombin-activatable fibrinolysis inhibitor (TAFI), fibrinogen and plasminogen activator inhibitor-1 (PAI-1) was performed. Expression was quantified using Orbit Image Software. Student's t-test was performed as appropriate. RESULTS: Mean TAFI content for the high estrogen state group was higher than controls (25.6 ± 11.9% versus 9.3 ± 9.0%, p = 0.043*). Mean platelet content for the high estrogen state group was lower than controls (41.7 ± 10.6% versus 61.8 ± 12.9%, p = 0.029*). No significant difference was found in vWF, fibrinogen and PAI-1 expression. Mean time to recanalize was higher in the high estrogen state group compared to the control group (57.8 ± 27.6 versus 22.6 ± 11.4 min, p = 0.0351*). The mean number of passes required was higher in the high estrogen group compared to controls 4.6 versus 1.2, p = 0.0261*). CONCLUSIONS: TAFI expression, a powerful driver of thrombosis, was significantly higher in stroke thrombi among patients with high estrogen states compared to controls.

Successful Treatment of Acquired Thrombotic Thrombocytopenic Purpura With Caplacizumab Combined With Plasma Exchanges and Immune Suppression in 3 Children.

Acquired thrombotic thrombocytopenic (aTTP) purpura is a life-threatening condition that can lead to devastating thromboembolic events. Recently, caplacizumab has been shown to rapidly restore platelet numbers and reduce the risk of severe end-organ damage when added to plasma exchanges (PEXs) and immunosuppression (IST). Here, we report the outcomes in 3 children with aTTP who were treated with caplacizumab in combination with PEXs and IST. In all 3 patients, platelet count increased to >15,000/mm 3 in 24 h and normalized on day 4, whereas normalization of ADAMTS13 activity >50% and elimination of the inhibitor was achieved after 18 to 89 days. Epistaxis was observed in 2 patients and was the only side effect related to caplacizumab. Caplacizumab is a promising agent for first-line treatment of children with aTTP.

A genetic association study of circulating coagulation factor VIII and von Willebrand factor levels.

ABSTRACT: Coagulation factor VIII (FVIII) and its carrier protein von Willebrand factor (VWF) are critical to coagulation and platelet aggregation. We leveraged whole-genome sequence data from the Trans-Omics for Precision Medicine (TOPMed) program along with TOPMed-based imputation of genotypes in additional samples to identify genetic associations with circulating FVIII and VWF levels in a single-variant meta-analysis, including up to 45 289 participants. Gene-based aggregate tests were implemented in TOPMed. We identified 3 candidate causal genes and tested their functional effect on FVIII release from human liver endothelial cells (HLECs) and VWF release from human umbilical vein endothelial cells. Mendelian randomization was also performed to provide evidence for causal associations of FVIII and VWF with thrombotic outcomes. We identified associations (P < 5 × 10-9) at 7 new loci for FVIII (ST3GAL4, CLEC4M, B3GNT2, ASGR1, F12, KNG1, and TREM1/NCR2) and 1 for VWF (B3GNT2). VWF, ABO, and STAB2 were associated with FVIII and VWF in gene-based analyses. Multiphenotype analysis of FVIII and VWF identified another 3 new loci, including PDIA3. Silencing of B3GNT2 and the previously reported CD36 gene decreased release of FVIII by HLECs, whereas silencing of B3GNT2, CD36, and PDIA3 decreased release of VWF by HVECs. Mendelian randomization supports causal association of higher FVIII and VWF with increased risk of thrombotic outcomes. Seven new loci were identified for FVIII and 1 for VWF, with evidence supporting causal associations of FVIII and VWF with thrombotic outcomes. B3GNT2, CD36, and PDIA3 modulate the release of FVIII and/or VWF in vitro.

A new look at an old body: molecular determinants of Weibel-Palade body composition and von Willebrand factor exocytosis.

Endothelial cells, forming a monolayer along blood vessels, intricately regulate vascular hemostasis, inflammatory responses, and angiogenesis. A key determinant of these functions is the controlled secretion of Weibel-Palade bodies (WPBs), which are specialized endothelial storage organelles housing a presynthesized pool of the hemostatic protein von Willebrand factor and various other hemostatic, inflammatory, angiogenic, and vasoactive mediators. This review delves into recent mechanistic insights into WPB biology, including the biogenesis that results in their unique morphology, the acquisition of intraluminal vesicles and other cargo, and the contribution of proton pumps to organelle acidification. Additionally, in light of a number of proteomic approaches to unravel the regulatory networks that control WPB formation and secretion, we provide a comprehensive overview of the WPB exocytotic machinery, including their molecular and cellular mechanisms.

Altered fibrin clot properties are associated with the progression of chronic kidney disease in atrial fibrillation.

INTRODUCTION: Formation of denser and resistant to lysis fibrin clot networks has been shown in chronic kidney disease (CKD) and atrial fibrillation (AF). We investigated whether such prothrombotic fibrin clot properties are associated with faster progression of CKD in AF patients. MATERIAL AND METHODS: We recruited 265 AF patients (men 49.1 %, median age of 64.0 years, median estimated glomerular filtration rate [eGFR] of 77.0 ml/min/1.73 m2), including 137 patients on non-vitamin K antagonist oral anticoagulants (NOACs) (51.7 %) and 109 patients (41.1 %) on vitamin K antagonists (VKAs). At baseline while off anticoagulation, we determined fibrin clot permeability (Ks), and clot lysis time (CLT), along with plasminogen activator inhibitor-1 (PAI-1), endogenous thrombin potential (ETP), and von Willebrand factor (vWF). The kidney function was assessed at baseline and after a median follow-up of 50.0 months. RESULTS: During follow-up, a median eGFR decreased by 8.0 (5.0-11.0) ml/min/1.73 m2, 1.8 ml/min/1.73 m2/year and this change correlated with age (R = 0.19, P = 0.002), Ks (R = 0.46, P < 0.0001), and CLT (R = -0.17, P = 0.005), but not ETP, fibrinogen, PAI-1 or vWF. A decrease in eGFR was lower in patients who used NOACs at baseline but not in those who started NOACs during follow-up (n = 101) as compared to the remaining patients. On multiple linear regression analysis, adjusted for age and fibrinogen, baseline Ks, eGFR, hypertension, and NOACs use independently predicted a decrease in eGFR. CONCLUSIONS: This study is the first to show that more compact fibrin clot networks may contribute to faster progression of CKD in AF, indicating novel kidney-related harmful effects of prothrombotic clot properties in humans.

VWD domain stabilization by autocatalytic Asp-Pro cleavage.

Domains known as von Willebrand factor type D (VWD) are found in extracellular and cell-surface proteins including von Willebrand factor, mucins, and various signaling molecules and receptors. Many VWD domains have a glycine-aspartate-proline-histidine (GDPH) amino-acid sequence motif, which is hydrolytically cleaved post-translationally between the aspartate (Asp) and proline (Pro). The Fc IgG binding protein (FCGBP), found in intestinal mucus secretions and other extracellular environments, contains 13 VWD domains, 11 of which have a GDPH cleavage site. In this study, we investigated the structural and biophysical consequences of Asp-Pro peptide cleavage in a representative FCGBP VWD domain. We found that endogenous Asp-Pro cleavage increases the resistance of the domain to exogenous proteolytic degradation. Tertiary structural interactions made by the newly generated chain termini, as revealed by a crystal structure of an FCGBP segment containing the VWD domain, may explain this observation. Notably, the Gly-Asp peptide bond, upstream of the cleavage site, assumed the cis configuration in the structure. In addition to these local features of the cleavage site, a global organizational difference was seen when comparing the FCGBP segment structure with the numerous other structures containing the same set of domains. Together, these data illuminate the outcome of GDPH cleavage and demonstrate the plasticity of proteins with VWD domains, which may contribute to their evolution for function in a dynamic extracellular environment.

The association between endothelial function and autoimmune thyroiditis induced by iodine excess.

BACKGROUND: Iodine excess (IE) intake leads to lymphocyte dysfunction and contributes to autoimmune thyroiditis (AIT). Abnormal thyroid function is associated with adverse cardiovascular events, endothelial dysfunction is often an early pathophysiological feature in most cardiovascular disease. However, the relationship between iodine and the cardiovascular system is currently unclear. Therefore, the aim of this study was to investigate the effects of IE on endothelial function in mouse model. METHODS: A total of 24 NOD.H-2h4 mice were randomly divided into different groups. A sodium iodide (NaI) group supplied with 0.05% NaI water for 8 weeks. Serum levels of tumor necrosis factors α (TNFα), interleukin-6 (IL-6) and C-reactive Protein (CRP), as well as endothelin-1 (ET-1), von Willebrand factor (VWF) and thrombomodulin (THBD) were detected by Elisa. In addition, the mRNA and protein expression of these genes were measured by RT-PCR and Western blotting. RESULTS: Here, we found the urinary iodine concentration (UIC) was higher in the NaI group compared to the control group. Serum levels of ET-1, VWF, and THBD were also significantly lower in the NaI group, however, CRP serum levels are significantly increased. In aorta, the mRNA and protein expression of ET-1, VWF, THBD were downregulated, however, the expression of IL-6, CRP and TNFα mRNA and protein were upregulated in the NaI group. A correlation analysis showed negative correlation between UIC with ET-1, VWF, and THBD, similarly, negative correlation between CRP with THBD was observed. In addition, positive correlations between UIC with CRP. CONCLUSION: Collectively, in the NOD.H-2h4 mice, IE supplementation had a suppressive effect on endothelial function, and this inhibition maybe due to the increase expression of inflammatory cytokines.