Elevated Selenoprotein P Levels in Thalassemia Major Patients.

INTRODUCTION: Previous studies have measured selenium levels and glutathione peroxidase 3 (GPX3) activity in patients with thalassemia major (TM). However, Selenoprotein P (SEPP), which is responsible for the storage and transport of selenium, has not been studied in thalassemia patients. This study aims to correlate thyroid functions of TM patients with their SEPP and GPX3 levels. MATERIALS AND METHODS: Eighty subjects (40 controls, 40 TM patients) were included in this study. GPX3 and SEPP concentrations were measured in all subjects using sandwich ELISA. Iron, ferritin, urinary iodine, thyroxine (T4), triiodothyronine (T3), thyrotropin (TSH), anti-thyroid peroxidase (anti-TPO), and anti-human thyroglobulin (anti-hTG) concentrations were also measured. RESULTS: Mean SEPP concentration was higher in the TM group compared to the control group. A slight elevation in GPX3 levels was also observed in thalassemia patients, yet it was not statistically significant. In both TM patients and controls, ferritin was inversely correlated with free T4 concentration and GPX3 was inversely correlated with free T4 and T3 concentrations. There was also a negative correlation between SEPP and TSH concentrations in healthy subjects. CONCLUSION: This is the first study, which has measured SEPP concentrations in thalassemia patients. SEPP levels were higher in TM patients compared to controls. Correlations between thyroid hormones and selenoproteins may indicate that selenium is necessary for thyroid function. Detailed studies are required to elaborate the role of SEPP in thyroid metabolism in thalassemia patients.

Comparative Study on the Chronic Vascular Responses Induced by Regular Versus Occasional Waterpipe Smoke Inhalation in Mice.

BACKGROUND/AIMS: Waterpipe smoke (WPS) is the second most prevalent form of smoking in the world. There are ample evidences about the vascular alterations caused by regular WPS (Reg-WPS). Nonetheless, comparison of the chronic vascular response induced by regular versus occasional WPS (Occ-WPS) exposure is very scarce. METHODS: We investigated, in BALB/c mice, the effects of Occ-WPS (30 minutes/day, 1 day/week) versus Reg-WPS (30 minutes/day, 5 days/week) for 6 months on thrombogenicity and platelet aggregation in vivo and in vitro. Moreover, various markers of endothelial integrity, inflammation and oxidative stress were assessed by enzyme-linked immunosorbent assay and colorimetric assay. Control mice were exposed to air. RESULTS: Our results showed that either Occ-WPS or Reg-WPS exposure shortened the thrombotic time in pial microvessels in vivo. Moreover, in pial venules, this effect was more marked in Reg-WPS group (-47%) compared with Occ-WPS (-34%). Similarly, exposure to either Occ-WPS or Reg-WPS reduced the prothrombin time and activated partial thromboplastin time. Platelet count was increased only in Reg-WPS exposure. Exposure to either Occ-WPS or Reg-WPS induced platelet aggregation in vitro. In addition, there was a statistically significant difference between Occ-WPS and Reg-WPS groups in platelet count and aggregation. Plasma concentration of tissue factor (+98%), P-selectin (+14%) and E-selectin (+16%) were significantly increased in Occ-WPS group compared with air exposed group. Likewise, compared with air group Reg-WPS caused an increase in concentration of tissue factor (+193%), P-selectin (+21%) and E-selectin (+42%). Nevertheless, only Reg-WPS induced a decrease (-38%) in the plasma concentration of tissue plasminogen activator. Notably, our results showed a statistically significant difference between Occ-WPS and Reg-WPS groups in the concentration of tissue factor. Erythrocyte numbers, hemoglobin concentration, hematocrit and lactate dehydrogenase activity were augmented only in Reg-WPS group compared with either control or Occ-WPS groups. Likewise, only Reg-WPS induced an increase in proinflammatory cytokines, tumor necrosis factor-α and interleukin-1ß compared with either control or Occ-WPS groups. However, markers of oxidative stress including 8-isoprostane and total antioxidants were enhanced in both Occ-WPS and Reg-WPS compared with control group. CONCLUSION: Our data confirm the vascular toxicity of the chronic Reg-WPS exposure and shows that even occasional chronic exposure to WPS caused thrombosis, platelet aggregation, endothelial alterations and oxidative stress. The latter findings are an additional cause of concern about the long-term toxicity of occasional waterpipe smoking.

Platelets mediate inflammatory monocyte activation by SARS-CoV-2 spike protein.

Infection with SARS-CoV-2, the causative agent of COVID-19, causes mild to moderate disease in most patients but carries a risk of morbidity and mortality. Seriously affected individuals manifest disorders of hemostasis and a cytokine storm, but it is not understood how these manifestations of severe COVID-19 are linked. Here, we showed that the SARS-CoV-2 spike protein engaged the CD42b receptor to activate platelets via 2 distinct signaling pathways and promoted platelet-monocyte communication through the engagement of P selectin/PGSL-1 and CD40L/CD40, which led to proinflammatory cytokine production by monocytes. These results explain why hypercoagulation, monocyte activation, and a cytokine storm are correlated in patients severely affected by COVID-19 and suggest a potential target for therapeutic intervention.

Serum thromboxane B2 but not soluble P-selectin levels identify ischemic stroke patients with persistent platelet reactivity while on aspirin therapy.

BACKGROUND: Aspirin non-response due to persistent platelet reactivity has been associated with adverse vascular events. Light transmission aggregometry (LTA), the 'gold standard' for measuring the platelet response to aspirin therapy, is a cumbersome procedure and a simple and reliable alternative is required. Our aim was to explore whether serum thromboxane B2 (sTXB2) and soluble P-selectin can be used to identify patients who are at risk of increased platelet reactivity while on aspirin. METHODS AND RESULTS: We recruited 293 ischemic stroke patients, taking aspirin for more than seven days, and performed LTA to classify them. Based on therapeutic serum salicylate levels, 63 patients were excluded due to suspected non-compliance, followed by ELISA measurement of TXB2 and P-selectin in serum. Accordingly, patients were classified into 'Responders' (n = 122, 53%), 'Semi-responders' (n = 76, 33%) and 'Non-responders' (n=32, 14%) by LTA. Patients who had platelet aggregation of ≥70% with 10µM ADP and ≥20% with 0.5mM AA were defined as 'Non-responders'. In comparison with 'Responders', 'Non-responders' had 8.63-fold increased risk of secondary vascular events (p = 0.008). ROC curve analysis revealed that sTXB2, at a cut-off level of >4.15 ng/mL, could distinguish the patient group with elevated platelet reactivity with a sensitivity of 84.3% (AUC = 0.84), and was in fair agreement with the LTA-based classification of patients. Soluble P-selectin levels, on the other hand, had no discriminatory ability. CONCLUSION: We suggest sTXB2 measurement as an alternative to the LTA approach for identifying aspirin-treated ischemic stroke patients who are at risk of enhanced platelet reactivity and subsequent vascular events.

Hemostatic Biomarkers and Venous Thromboembolism Are Associated With Mortality and Response to Chemotherapy in Patients With Pancreatic Cancer.

Objective: Pancreatic cancer activates coagulation and increases risk of venous thromboembolism (VTE). We aimed at characterizing the association of hemostatic biomarkers and VTE with mortality and chemotherapy response. Approach and Results: Pancreatic cancer patients (N=145) were included in a prospective, observational cohort study (CATS [Vienna Cancer and Thrombosis Study]). Hemostatic biomarkers (D-dimer, extracellular vesicle-tissue factor activity, prothrombin fragment 1+2, fibrinogen, factor VIII, PAI-1 [plasminogen activator inhibitor 1], sP-selectin [soluble P-selectin], thrombin generation assay) were measured at inclusion. The impact of VTE on overall survival/progression-free survival (OS/PFS) was evaluated by multistate modeling. The association of biomarkers with OS was analyzed by Cox-regression and with PFS and disease control rate in patients initiating palliative chemotherapy (n=95) by Cox-regression and logistic regression. Multivariable analysis included stage, grade, sex, age, performance status, VTE (time-dependent), vascular infiltration/compression, and tumor marker levels (carbohydrate-antigen 19-9, carcinoembryonic antigen). VTE occurrence was associated with shorter OS (transition hazard ratio, 3.40 [95% CI, 2.05-5.64]) and shorter PFS (transition hazard ratio, 2.10 [1.16-3.79]). Median post-VTE OS/PFS in months was 5.5 [2.2-6.5] and 3.0 [1.5-3.9], compared with 13.4 [9.7-16.6] and 7.5 [5.9-9.8] in patients without VTE (both P<0.001). D-dimer, extracellular vesicle-tissue factor activity, PAI-1, and sP-selectin were associated with increased mortality (hazard ratio per doubling, 1.27 [1.00-1.61]; 1.63 [1.14-2.36]; 1.25 [1.06-1.47]; 1.52 [1.05-2.20]). In patients initiating palliative chemotherapy, higher D-dimer predicted shorter PFS (hazard ratio per doubling, 1.27 [1.01-1.60]) and lower disease control rate (odds ratio per doubling, 0.59 [0.36-0.98]). Conclusions: VTE diagnosis is associated with shorter OS and PFS. Higher baseline levels of D-dimer, extracellular vesicle-tissue factor activity, PAI-1, and sP-selectin were independently prognostic for increased mortality, and D-dimer predicted response to palliative chemotherapy.

Further Findings Concerning Endothelial Damage in COVID-19 Patients.

Systemic vascular damage with micro/macro-thrombosis is a typical feature of severe COVID-19. However, the pathogenesis of this damage and its predictive biomarkers remain poorly defined. For this reason, in this study, serum monocyte chemotactic protein (MCP)-2 and P- and E-selectin levels were analyzed in 204 patients with COVID-19. Serum MCP-2 and P-selectin were significantly higher in hospitalized patients compared with asymptomatic patients. Furthermore, MCP-2 increased with the WHO stage in hospitalized patients. After 1 week of hospitalization, MCP-2 levels were significantly reduced, while P-selectin increased in patients in WHO stage 3 and decreased in patients in WHO stages 5-7. Serum E-selectin was not significantly different between asymptomatic and hospitalized patients. The lower MCP-2 levels after 1 week suggest that endothelial damage triggered by monocytes occurs early in COVID-19 disease progression. MCP-2 may also predict COVID-19 severity. The increase in P-selectin levels, which further increased in mild patients and reduced in severe patients after 1 week of hospitalization, suggests that the inactive form of the protein produced by the cleavage of the active protein from the platelet membrane is present. This may be used to identify a subset of patients that would benefit from targeted therapies. The unchanged levels of E-selectin in these patients suggest that endothelial damage is less relevant.

Platelet features allow to differentiate immune thrombocytopenia from inherited thrombocytopenia.

Immune thrombocytopenia (ITP) is an acquired bleeding disorder, for which no specific diagnostic test exists. Inherited thrombocytopenia (IT) can mimic ITP and lead to unappropriated management with significant morbidity. Here, in small cohorts of these two disorders, we explored whether platelet sialylation and platelet activation could allow to discriminate the two conditions. We also aimed to confirm the value of immature platelet counts in this discrimination. Platelet sialylation and the expression level of P-selectin were assessed by multiparameter flow cytometry. Immature platelets were estimated on a Sysmex XN 9000 analyzer. No significant difference in platelet sialylation was observed between ITP and IT. Contrarily, platelet activation was significantly higher in ITP patients (p = 0.008). The immature platelet fraction, as previously demonstrated, was significantly lower in the ITP group compared to the IT group (p = 0.014). That statistical significance was achieved in this small pilot study suggests that the two easily available assays of immature platelet count and P-selectin expression could help physicians to reach the proper diagnosis in complex cases of thrombocytopenia.

The Role of P-Selectin in COVID-19 Coagulopathy: An Updated Review.

In severe COVID-19, which is characterized by blood clots and neutrophil-platelet aggregates in the circulating blood and different tissues, an increased incidence of cardiovascular complications and venous thrombotic events has been reported. The inflammatory storm that characterizes severe infections may act as a driver capable of profoundly disrupting the complex interplay between platelets, endothelium, and leukocytes, thus contributing to the definition of COVID-19-associated coagulopathy. In this frame, P-selectin represents a key molecule expressed on endothelial cells and on activated platelets, and contributes to endothelial activation, leucocyte recruitment, rolling, and tissue migration. Briefly, we describe the current state of knowledge about P-selectin involvement in COVID-19 pathogenesis, its possible use as a severity marker and as a target for host-directed therapeutic intervention.

Dose-dependent effects of anthocyanin supplementation on platelet function in subjects with dyslipidemia: A randomized clinical trial.

BACKGROUND: Dyslipidemia induces platelet hyperactivation and hyper-aggregation, which are linked to thrombosis. Anthocyanins could inhibit platelet function in vitro and in mice fed high-fat diets with their effects on platelet function in subjects with dyslipidemia remained unknown. This study aimed to investigate the effects of different doses of anthocyanins on platelet function in individuals with dyslipidemia. METHODS: A double-blind, randomized, controlled trial was conducted. Ninety-three individuals who were initially diagnosed with dyslipidemia were randomly assigned to placebo or 40, 80, 160 or 320 mg/day anthocyanin groups. The supplementations were anthocyanin capsules (Medox, Norway). Platelet aggregation by light aggregometry of platelet-rich plasma, P-selectin, activated GPⅡbⅢa, reactive oxygen species (ROS), and mitochondrial membrane potential were tested at baseline, 6 weeks and 12 weeks. FINDINGS: Compared to placebo group, anthocyanins at 80 mg/day for 12 weeks reduced collagen-induced platelet aggregation (-3.39±2.36%) and activated GPⅡbⅢa (-8.25±2.45%) (P < 0.05). Moreover, compared to placebo group, anthocyanins at 320 mg/day inhibited collagen-induced platelet aggregation (-7.05±2.38%), ADP-induced platelet aggregation (-7.14±2.00%), platelet ROS levels (-14.55±1.86%), and mitochondrial membrane potential (7.40±1.56%) (P < 0.05). There were dose-response relationships between anthocyanins and the attenuation of platelet aggregation, mitochondrial membrane potential and ROS levels (P for trend <0.05). Furthermore, significantly positive correlations were observed between changes in collagen-induced (r = 0.473) or ADP-induced (r = 0.551) platelet aggregation and ROS levels in subjects with dyslipidemia after the 12-week intervention (P < 0.05). INTERPRETATION: Anthocyanin supplementation dose-dependently attenuates platelet function, and 12-week supplementation with 80 mg/day or more of anthocyanins can reduce platelet function in individuals with dyslipidemia. FUNDING: None.

Thrombopoietin Contributes to Enhanced Platelet Activation in Patients with Type 1 Diabetes Mellitus.

Atherosclerotic cardiovascular disease is the major cause of morbidity and mortality in patients with type 1 diabetes mellitus (T1DM). Enhanced platelet reactivity is considered a main determinant of the increased atherothrombotic risk of diabetic patients. Thrombopoietin (THPO), a humoral growth factor able to stimulate megakaryocyte proliferation and differentiation, also modulates the response of mature platelets by enhancing both activation and binding to leukocytes in response to different agonists. Increased THPO levels have been reported in different clinical conditions characterized by a generalized pro-thrombotic state, from acute coronary syndromes to sepsis/septic shock, and associated with elevated indices of platelet activation. To investigate the potential contribution of elevated THPO levels in platelet activation in T1DM patients, we studied 28 T1DM patients and 28 healthy subjects. We measured plasma levels of THPO, as well as platelet-leukocyte binding, P-selectin, and THPO receptor (THPOR) platelet expression. The priming activity of plasma from diabetic patients or healthy subjects on platelet-leukocyte binding and the role of THPO on this effect was also studied in vitro. T1DM patients had higher circulating THPO levels and increased platelet-monocyte and platelet-granulocyte binding, as well as platelet P-selectin expression, compared to healthy subjects, whereas platelet expression of THPOR did not differ between the two groups. THPO concentrations correlated with platelet-leukocyte binding, as well as with fasting glucose and Hb1Ac. In vitro, plasma from diabetic patients, but not from healthy subjects, primed platelet-leukocyte binding and platelet P-selectin expression. Blocking THPO biological activity using a specific inhibitor prevented the priming effect induced by plasma from diabetic patients. In conclusion, augmented THPO may enhance platelet activation in patients with T1DM, potentially participating in increasing atherosclerotic risk.

A Single-Center Clinical Study to Evaluate Shenxiong Glucose Injection Combined with Edaravone in the Treatment of Acute Large-Area Cerebral Infarction.

OBJECTIVES: To investigate the clinical efficacy and safety of Shenxiong glucose injection combined with edaravone in the treatment of acute large-area cerebral infarction. METHODS: 156 patients with acute large-area cerebral infarction admitted to our hospital from July 2015 to January 2017 were included in the analysis. The patients were randomly divided into experimental (78 cases) and control (78 cases) groups. Patients in the experimental group were given a 30 mg injection of edaravone in 100 ml of 0.9% sodium chloride solution by intravenous drip, twice a day within 30 minutes and a daily 200 ml injection of Shenxiong glucose by intravenous drip. Patients in the control group were given a 30 mg edaravone injection in 100 ml of 0.9% sodium chloride solution by intravenous drip, twice a day, and the drip was completed within 30 minutes. Patients in both groups were treated for 2 weeks. The levels of fibrinogen (FIB), D-dimer, interleukin 6 (IL-6), P-selectin (CD62P), and hypersensitive C-reactive protein (hs-CRP) were evaluated in the two groups of patients. Neurological disability was evaluated using the modified Rankin scale (mRS) and the neurological deficit score (National Institute of Health Stroke Scale, NIHSS). Adverse reactions to the treatments were also recorded. RESULTS: No significant differences in age, gender, medical histories, and blood biochemical indices were observed between the two groups before treatment (P > 0.05). After treatment, the levels of FIB, D-dimer, IL-6, CD62P, and hs-CRP were significantly lower following treatment and compared to the control group (P < 0.05). Also, the mRS and NIHSS scores were significantly lower after treatment and compared with the control group (P < 0.05). The total effective rate of the treatment in the experimental group was significantly higher compared to the control group (P < 0.05). During the treatment period, no obvious adverse reactions were observed in the two groups of patients. CONCLUSIONS: In addition to the routine basic treatment of acute large-area cerebral infarction, the addition of Shenxiong glucose injection combined with edaravone injection can improve platelet aggregation and reduce inflammation by affecting P-selectin, D-dimer, and FIB. This treatment approach promotes the recovery of nerve defect function without obvious adverse reactions in patients with acute large-area cerebral infarction.

Endothelial microparticle-associated protein disulfide isomerase increases platelet activation in diabetic coronary heart disease.

BACKGROUND: Endothelial microparticles (EMPs) carrying the protein disulfide isomerase (PDI) might play a key role in promoting platelet activation in diabetes. This study aimed to examine the activation of platelets, the amounts of MPs, PMPs, and EMPs, and the concentration and activity of PDI in patients with diabetic coronary heart disease (CHD) and non-diabetic CHD. METHODS: Patients with CHD (n=223) were divided as non-diabetic CHD (n=121) and diabetic CHD (n=102). Platelet activation biomarkers, circulating microparticles (MPs), the concentration of protein disulfide isomerase (PDI), and MP-PDI activity were determined. The effect of EMPs on platelet activation was investigated in vitro. Allosteric GIIb/IIIa receptors that bind to PDI were detected by a proximity ligation assay (PLA). RESULTS: Platelet activation, platelet-leukocyte aggregates, circulating MPs, EMPs, PDI, and MP-PDI activity in the diabetic CHD group were significantly higher than in the non-diabetic CHD group (P<0.05). Diabetes (P=0.006) and heart rate <60 bpm (P=0.047) were associated with elevated EMPs. EMPs from diabetes increased CD62p on the surface of the platelets compared with the controls (P<0.01), which could be inhibited by the PDI inhibitor RL90 (P<0.05). PLA detected the allosteric GIIb/IIIa receptors caused by EMP-PDI, which was also inhibited by RL90. CONCLUSIONS: In diabetic patients with CHD, platelet activation was significantly high. Diabetes and heart rate <60 bpm were associated with elevated EMPs and simultaneously increased PDI activity on EMP, activating platelets through the allosteric GPIIb/IIIa receptors.

Left Atrial Appendage Morphology and Local Thrombogenesis-Related Blood Parameters in Patients With Atrial Fibrillation.

Background Left atrial appendage (LAA) morphology predicts stroke risk in patients with atrial fibrillation. However, it is not precisely understood how LAA morphology influences stroke risk. The present study aimed to investigate the relationship between LAA morphology and local thrombogenesis-related blood parameters in LAA. Methods and Results We enrolled 205 patients undergoing catheter ablation of atrial fibrillation. The prevalence of chicken wing-, cactus-, windsock-, and cauliflower-type LAAs were 23.9%, 32.7%, 29.3%, and 14.1%, respectively. Blood samples were collected from the femoral vein, left atrium, and LAA in each patient. The levels of blood parameters were tested for each blood sample. The cauliflower-type LAA was associated with elevated platelet P-selectin expression, and interleukin-6 levels and with lower NO levels in LAA blood samples (P<0.05) independent of LAA flow velocity and LAA volume. LAA flow velocity, which was lowest in the cauliflower-type LAA, was the only independent predictor of von Willebrand factor antigen and plasminogen activator inhibitor-1 levels in LAA blood samples. In femoral vein blood samples, no significant difference was detected in the above blood parameters among the four LAA morphological types. In all blood samples, the levels of thrombin-antithrombin complex, D-dimer, fibrinogen, and tissue plasminogen activator were comparable among the four LAA morphological types. Conclusions In patients with atrial fibrillation, LAA morphological types might be associated with local platelet activity, fibrinolysis function, endothelial dysfunction, and inflammation.

Platelet-enhanced plasma: Characterization of a novel candidate resuscitation fluid's extracellular vesicle content, clotting parameters, and thrombin generation capacity.

BACKGROUND: Platelet transfusion is challenging in emergency medicine because of short platelet shelf life and stringent storage conditions. Platelet-derived extracellular vesicles (PEV) exhibit platelet-like properties. A plasma generated from expired platelet units rich in procoagulant PEV may be able to combine the benefits of plasma and platelets for resuscitation while increasing shelf life and utilizing an otherwise wasted resource. STUDY DESIGN AND METHODS: Freeze-thaw cycling of platelet-rich plasma (PRP) followed by centrifugation to remove platelet remnants was utilized to generate platelet-enhanced plasma (PEP). An in vitro model of dilutional coagulopathy was also designed and used to test PEP. Rotational thromboelastometry and calibrated automated thrombography were used to assess clotting and extracellular vesicles (EV) procoagulant activity. Capture arrays were used to specifically measure EV subpopulations of interest (ExoView™, NanoView Biosciences). Captured vesicles were quantified and labeled with Annexin-V-FITC, CD41-PE, and CD63-AF647. Platelet alpha granule content (platelet-derived growth factor AB, soluble P-selectin, vascular endothelial growth factor A, and neutrophil activating peptide 2-chemokine (C-X-C motif) ligand 7) was measured. Commercially available platelet lysates were also characterized. RESULTS: PEP is highly procoagulant, rich in growth factors, exhibits enhanced thrombin generation, and restores hemostasis within an in vitro model of dilutional coagulopathy. The predominant vesicle population were PEV with 7.0 × 109 CD41+PS+ EV/ml compared to 4.7 × 107 CD41+PS+ EV/ml in platelet-free plasma (p = .0079). Commercial lysates show impaired but rescuable clotting. DISCUSSION: PEP is a unique candidate resuscitation fluid containing high PEV concentration with preliminary evidence, indicating a potential for upscaling the approach using platelet concentrates. Commercial lysate manufacturer workflows may be suitable for this, but further optimization and characterization of PEP is required.

Linking Neutrophil Extracellular Traps and Platelet Activation: A Composite Biomarker Score for Predicting Outcomes after Acute Myocardial Infarction.

BACKGROUND: Activation of both platelets and neutrophils can contribute to the risk of major adverse cardiovascular events (MACE) following acute myocardial infarction (AMI). Neutrophil extracellular traps (NETs) are an important product of the platelet-neutrophil axis and exaggerate vascular damage in cardiovascular disease. Additionally, activated platelets can drive NETosis and are directly linked to thromboembolic risk. Investigating the combined effect of biomarkers for NETosis and platelet activation represents a novel approach to risk prediction post-AMI. Here, we examined the utility of a composite biomarker score, inclusive of both pathways, for predicting MACE post-AMI. METHODS AND RESULTS: In a case-control design, 100 case patients who experienced MACE within 1 year of index admission were matched in a 1:2 ratio with control patients. Serum levels of myeloperoxidase-DNA, neutrophil elastase-DNA, and citrullinated histone H3 were assayed by enzyme-linked immunosorbent assay (ELISA) as markers of NET burden. To measure platelet activation, soluble P-selectin was assayed by ELISA in parallel. Platelet and neutrophil counts were also recorded. Composite biomarker scores, inclusive of biomarkers for NETosis and platelet activation, were assessed using multivariate regression modeling. These composite biomarker scores were independent predictors of 1-year MACE. The strongest association with MACE was observed using a composite of platelet count, soluble P-selectin, and all NET markers (odds ratio: 1.94; 1.16-3.25). CONCLUSION: Here, we demonstrate the importance of combining biomarkers of NETosis and platelet activation for risk prediction in patients with AMI. Combining biomarkers from closely linked, but distinct, biological pathways was more effective than utilizing either type of biomarker alone.

Soluble P-selectin as a potential diagnostic and prognostic biomarker for COVID-19 disease: A case-control study.

INTRODUCTION: To our knowledge, the diagnostic value of the sP-Selectin level in the diagnosis of COVID-19 disease has not yet been investigated. In this study, we aimed to assess this by evaluating the relationship between sP-Selectin level and the clinical severity of COVID-19 infections. METHODS: A total of 80 patients (50 with mild to moderate and 30 with severe COVID-19 pneumonia), and 60 non-symptomatic healthy volunteers participated in the study. Following serum isolation, sP-Selectin levels were assessed by Enzyme-Linked Immunosorbent Assay (ELISA) method. RESULTS: The serum sP-Selectin level was 1.7 ng/ml in the control group (1-3.78); 6.24 ng/ml (5.14-7.23) in mild-to-moderate pneumonia group; and 6.72 ng/ml (5.36-8.03) in the severe pneumonia group. Serum sP-Selectin levels in both mild-to-moderate pneumonia and severe pneumonia groups were found to be higher than the control group, with statistical significance (p = 0.0001 and p = 0.0001, respectively). Receiver operating characteristic analysis (ROC) showed greater area under the curve (AUC) for the serum sP-Selectin levels of the COVID-19 patients (AUC = 0.913, 95% CI = 0.857-0.969; p = 0.0001). The serum sP-Selectin level was found to be 97.5% sensitive and 80% specific at 4.125 ng/ml level for diagnosis (p = 0.0001). The serum sP-Selectin level was found to be 76.9% sensitive and 51.9% specific at the level of 6.12 ng/ml (p = 0.005) to predict the need for intensive care treatment. CONCLUSION: This study showed that sP-Selectin can be used as a valuable biomarker in both diagnosing and predicting the need for intensive care treatment of COVID-19 infection.

Inflammatory and Prothrombotic Biomarkers Associated With the Severity of COVID-19 Infection.

Among COVID-19 hospitalized patients, high incidence of alterations in inflammatory and coagulation biomarkers correlates with a poor prognosis. Comorbidities such as chronic degenerative diseases are frequently associated with complications in COVID-19 patients. The aim of this study was to evaluate inflammatory and procoagulant biomarkers in COVID-19 patients from a public hospital in Mexico. Blood was sampled within the first 48 h after admission in 119 confirmed COVID-19 patients that were classified in 3 groups according to oxygen demand, evolution and the severity of the disease as follows: 1) Non severe: nasal cannula or oxygen mask; 2) Severe: high flow nasal cannula and 3) Death: mechanical ventilation eventually leading to fatal outcome. Blood samples from 20 healthy donors were included as a Control Group. Analysis of inflammatory and coagulation biomarkers including D-dimer, interleukin 6, interleukin 8, PAI-1, P-selectin and VWF was performed in plasma. Routine laboratory and clinical biomarkers were also included and compared among groups. Concentrations of D-dimer (14.5 ± 13.8 µg/ml) and PAI-1 (1223 ± 889.6 ng/ml) were significantly elevated in severe COVID-19 patients (P < 0.0001). A significant difference was found in interleukin-6, PAI-1 and P-selectin in non-severe and healthy donors when compared to Severe COVID-19 and deceased patients (P < 0.001). VWF levels were also significantly different between severe patients (153.5 ± 24.3 UI/dl) and non-severe ones (133.9 ± 20.2 UI/dl) (P < 0.0001). WBC and glucose levels were also significantly elevated in patients with Severe COVID-19. Plasma concentrations of all prothrombotic biomarkers were significantly higher in patients with a fatal outcome.

Inflammatory Biomarkers in the Short-Term Prognosis of Venous Thromboembolism: A Narrative Review.

The relationship between inflammation and venous thrombosis is not well understood. An inflammatory response may be both the cause and consequence of venous thromboembolism (VTE). In fact, several risk factors of VTE modulate thrombosis through inflammatory markers. Acute pulmonary embolism (PE) is burdened by a remarkable mortality rate, up to 34% in severely ill patients presenting with hemodynamic instability. Initial mortality risk stratification is based on hemodynamic instability. Patients with a situation of hemodynamic stability require immediate further risk assessment based on clinical, imaging, and circulating biomarkers, as well as the presence of comorbidities. Some inflammatory biomarkers have shown potential usefulness in the risk stratification of patients with VTE, especially acute PE. C-reactive protein on admission is associated with 30-day mortality and bleeding in VTE patients. P-selectin is associated with right ventricle dysfunction in PE patients and might be associated with VTE recurrences and the extension of thrombosis. Tissue factor microparticles are associated with VTE recurrence in cancer-associated thrombosis. Other inflammatory biomarkers present scarce evidence (inflammatory cytokines, erythrocyte sedimentation rate, fibrinogen, leukocyte count). In this manuscript, we will review the prognostic role of different inflammatory biomarkers available both for clinical practice and research in VTE patients.

Influence of Lipid Excipients on Platelet Function and the Pharmacodynamic Effects of Aspirin.

ABSTRACT: The combination of pharmaceutical lipid excipients with aspirin in a novel liquid oral formulation (Vazalore) limits gastrointestinal toxicity of aspirin. This study was performed to determine whether the lipid excipients influence the pharmacodynamic effects of aspirin and whether the excipients directly affect platelet function. The pharmacodynamic effects of aspirin were assessed over a range of concentrations designed to exert limited to maximal inhibition of cyclooxygenase-1 (COX1) necessary for thromboxane A2 production. Platelet aggregation induced by arachidonic acid and assessed with the use of light transmission aggregometry was used as a direct measure of the inhibition of COX1 by aspirin. Flow cytometry was used to assess the direct effect of excipients on platelet function. Twice the ratio of lipid excipient to aspirin used in the formulation of the novel oral agent was used. Blood was taken from 20 healthy subjects and anticoagulated with trisodium citrate (3.2%, 1:10 vol/vol). Aspirin and excipients were added in vitro and incubated for 10 minutes before performance of light transmission aggregometry and flow cytometry. The excipients did not limit the pharmacodynamic effects of aspirin. When the extent of inhibition of platelet aggregation was limited, the excipients tended to enhance pharmacodynamic effects. The excipients did not activate platelets in the absence of agonist and did not alter activation of platelets in response to adenosine diphosphate, arachidonic acid, thrombin, or convulxin (a collagen mimetic). Lipid excipients used in an oral formulation of aspirin do not impair the pharmacodynamic effects of aspirin and do not alter platelet function.