The hemostatic system as a modulator of atherosclerosis

Protease-activated receptors in vascular smooth muscle cells: a bridge between thrombo-inflammation and vascular remodelling

Coagulation factors are responsible for blood clot formation yet have also non-canonical functions as signalling molecules. In this context, they can activate protease-activated receptors (PARs) ubiquitously expressed in the vasculature. During vascular repair, vascular smooth muscle cells (VSMCs) will switch from a contractile to a synthetic reparative phenotype. During prolonged vascular stress, VSMCs acquire a pathological phenotype leading to cardiovascular disease. Activated coagulation factors impact on vessel wall permeability and integrity after vascular injury with a key role for PAR activation on endothelial cells. The activation of PARs on VSMCs supports vessel wall repair following injury. Prolonged PAR activation, however, results in pathological vascular remodelling. Therefore, understanding the mechanisms of PAR activation on VSMCs is key to propel our understanding of the molecular and cellular mechanisms to develop novel therapeutic strategies to resolve vascular remodelling.In this review, we discuss recent advances on the role of PAR signalling on VSMCs and specifically their role in vascular remodelling contributing to cardiovascular disease. Additionally, we discuss current therapeutic strategies targeting PAR signalling - indirectly or directly - in relation to cardiovascular disease.

White Depressed Areas and Tumor Infiltrating Lymphocytes: The Cancer Cure That Lies Within?

This brief overview is inspired by seminal contributions by the late Dr. Martin C. Mihm, Jr. who provided a basis for recognition and better understanding of interactions between lymphocytes (tumor-infiltrating lymphocytes [TILs]) that home to and permeate cancers. In primary melanomas, this phenomenon may produce what Dr. Mihm called white depressed areas, prescient clues to what would fuel future attempts at harnessing anticancer immunity. The critical and sequential TIL attributes of antigenic stimulation, homing, and effector-target cell apoptotic injury herein are briefly reviewed in light of more recent advances in the field of immuno-oncology. The intent is to emphasize how fundamental clinical and histopathological observations, as forged by Dr. Mihm and his associates, have led to critically important prognostic paradigms as well as to translational insights that now have become transformative in the field of cancer immunotherapy.

Randomized Comparison of Progression of Atherosclerotic Plaques and Calcification of Coronary Artery in Atrial Fibrillation Patients Treated With Edoxaban Versus Warfarin (The REPRESENT-AF trial)

Although the adverse effects of long-term use of vitamin K oral anticoagulant (OAC), warfarin, on the coronary vasculature are well-established, it remains unknown whether nonvitamin K oral anticoagulants play a role in the attenuation of plaque progression and coronary calcification. This study aimed to compare the changes in atherosclerotic plaques and calcification of the coronary arteries in patients with atrial fibrillation (AF) treated with edoxaban and warfarin. A total of 150 OAC-naïve patients with AF and atherosclerotic lesions on coronary computed tomography angiography (CCTA) were enrolled and randomly assigned to the edoxaban or warfarin treatment groups. All enrolled patients received rosuvastatin 10 mg and 119 patients completed the entire study protocol. A total of 12 months after the assigned OAC treatment, follow-up CCTA was performed and changes in plaque and calcium volumes of the coronary arteries were analyzed. The baseline characteristics of the 2 groups were well-balanced. The percentage of time in therapeutic range in the warfarin group was 61.1%. Compared with the baseline CCTA, there was a significant reduction in plaque volume after 12 months of OAC and rosuvastatin administration in both groups, and the extent of regression did not differ significantly between the groups. The increase in calcium volume was greater in the warfarin group than in the edoxaban group; however, the difference was not significant. In OAC-naïve patients with AF and atherosclerotic coronary lesions who were treated with moderate-intensity statin, edoxaban use did not have a positive effect on atherosclerotic plaques and coronary calcification compared with warfarin use over a 12-month follow-up period.

One immune cell to bind them all: platelet contribution to neurodegenerative disease

Alzheimer's disease (AD) and related dementias (ADRD) collectively affect a significant portion of the aging population worldwide. The pathological progression of AD involves not only the classical hallmarks of amyloid beta (Aβ) plaque buildup and neurofibrillary tangle development but also the effects of vasculature and chronic inflammatory processes. Recently, platelets have emerged as central players in systemic and neuroinflammation. Studies have shown that patients with altered platelet receptor expression exhibit accelerated cognitive decline independent of traditional risk factors. Additionally, platelets from AD patients exhibit heightened unstimulated activation compared to control groups. Platelet granules contain crucial AD-related proteins like tau and amyloid precursor protein (APP). Dysregulation of platelet exocytosis contributes to disease phenotypes characterized by increased bleeding, stroke, and cognitive decline risk. Recent studies have indicated that these effects are not associated with the quantity of platelets present in circulation. This underscores the hypothesis that disruptions in platelet-mediated inflammation and healing processes may play a crucial role in the development of ADRD. A thorough look at platelets, encompassing their receptors, secreted molecules, and diverse roles in inflammatory interactions with other cells in the circulatory system in AD and ADRD, holds promising prospects for disease management and intervention. This review discusses the pivotal roles of platelets in ADRD.

Mitigating Vascular Inflammation by Mimicking AIBP Mechanisms: A New Therapeutic End for Atherosclerotic Cardiovascular Disease

Atherosclerosis, characterized by the accumulation of lipoproteins and lipids within the vascular wall, underlies a heart attack, stroke, and peripheral artery disease. Endothelial inflammation is the primary component driving atherosclerosis, promoting leukocyte adhesion molecule expression (e.g., E-selectin), inducing chemokine secretion, reducing the production of nitric oxide (NO), and enhancing the thrombogenic potential. While current therapies, such as statins, colchicine, anti-IL1β, and sodium-glucose cotransporter 2 (SGLT2) inhibitors, target systemic inflammation, none of them addresses endothelial cell (EC) inflammation, a critical contributor to disease progression. Targeting endothelial inflammation is clinically significant because it can mitigate the root cause of atherosclerosis, potentially preventing disease progression, while reducing the side effects associated with broader anti-inflammatory treatments. Recent studies highlight the potential of the APOA1 binding protein (AIBP) to reduce systemic inflammation in mice. Furthermore, its mechanism of action also guides the design of a potential targeted therapy against a particular inflammatory signaling pathway. This review discusses the unique advantages of repressing vascular inflammation or enhancing vascular quiescence and the associated benefits of reducing thrombosis. This approach offers a promising avenue for more effective and targeted interventions to improve patient outcomes.

Predictive role of hematological indices in patients with acute coronary syndrome in Ethiopia: Intrahospital outcomes

Background

Apart from troponins, various additional biomarkers that indicate myocardial injury, inflammation, thrombosis, and other routes are being studied to improve the treatment of acute coronary syndrome (ACS). Myeloid activity has been found to be elevated in ACS, and this has sparked a great deal of interest in hematological parameters since they might offer independent insights into pathophysiology and risk assessment.

Objective

The purpose of this study was to evaluate the hematological markers' prognostic ability for all intrahospital causes of mortality in individuals with an ACS diagnosis.

Methods

A long-term cohort study based at an institution was done. At Jimma Medical Center, patients with an ACS diagnosis were progressively brought in between May 1, 2022, and October 31, 2023. Complete blood counts (CBC) and biochemical analysis were carried out. Multilevel mixed effect logistic regression was computed to evaluate the predictive competence of hematological indices on intrahospital mortality. Prognostic performance of hematological parameters was done using the ROC curve analysis.

Result

A total of 110 patients were included, of which 99 (90 %) were diagnosed ST-elevation myocardial infarction, and 74 (67.3 %) were men. The mean age was 56 (±11) years. RDW, platelet count, and MCV were independently associated with intrahospital mortality (AOR = 1.20 with P < 0.001, AOR = 0.995 with P < 0.03, and AOR = 0.897 with P < 0.025, respectively). The predictive power of RDW-SD for intrahospital mortality was evaluated by ROC analysis, the AUC value were 0.737 (95 % CI 0.669-0.805).

Conclusion

This study found that red cell distribution width, mean corpuscular volume, and platelets were predictive factors for intrahospital death in patients with ACS. Thus, it is possible to predict the prognosis of an ACS patient using hematological data.

Plasma levels of complement components C5 and C9 are associated with thrombin generation

BACKGROUND

The thrombin generation assay (TGA) evaluates the potential of plasma to generate thrombin over time, providing a global picture of an individual's hemostatic balance.

OBJECTIVES

This study aimed to identify novel biological determinants of thrombin generation using a multiomics approach.

METHODS

Associations between TGA parameters and plasma levels of 377 antibodies targeting 236 candidate proteins for cardiovascular risk were tested using multiple linear regression analysis in 770 individuals with venous thrombosis from the Marseille Thrombosis Association (MARTHA) study. Proteins associated with at least 3 TGA parameters were selected for validation in an independent population of 536 healthy individuals (Etablissement Français du Sang Alpes-Méditerranée [EFS-AM]). Proteins with strongest associations in both groups underwent additional genetic analyses and in vitro experiments.

RESULTS

Eighteen proteins were associated (P < 1.33 × 10⁻4) with at least 3 TGA parameters in MARTHA, among which 13 demonstrated a similar pattern of associations in EFS-AM. Complement proteins C5 and C9 had the strongest associations in both groups. Ex vivo supplementation of platelet-poor plasma with purified C9 protein had a significant dose-dependent effect on TGA parameters. No effect was observed with purified C5. Several single nucleotide polymorphisms associated with C5 and C9 plasma levels were identified, with the strongest association for the C5 missense variant rs17611, which was associated with a decrease in C5 levels, endogenous thrombin potential, and peak in MARTHA. No association of this variant with TGA parameters was observed in EFS-AM.

CONCLUSION

This study identified complement proteins C5 and C9 as potential determinants of thrombin generation. Further studies are warranted to establish causality and elucidate the underlying mechanisms.

The endocrine disruptor vinclozolin causes endothelial injury via eNOS/Nox4/IRE1α signaling

Vinclozolin (VCZ) is a common dicarboximide fungicide used to protect crops from diseases. It is also an endocrine disruptor, and its effects on various organs have been described but its influence on vasculature has not yet been addressed. This study focuses on the potential mechanism of VCZ-induced vascular injury. The effect of VCZ on vascular function in terms of relaxing and contracting response was evaluated in mice aorta. A short exposure to VCZ affected the endothelial but not the smooth muscle component. Specifically, it caused a disruption of the eNOS/NO signaling. In line, a short exposure to VCZ in bovine aortic endothelial cells promoted eNOS uncoupling resulting in a reduction of NO bioavailability and eNOS dimer/monomer ratio, and in turn an increase of nitro-tyrosine levels and ROS formation. Prolonging the exposure to VCZ (3 and 6h) an up-regulation of Nox4, enzyme-generating ROS constitutively expressed in endothelial cells, and an increase in ROS and malondialdehyde content coupled with a reduction in NO levels were found. These events were strictly linked to endoplasmic reticulum stress as demonstrated by the phosphorylation of inositol-requiring transmembrane kinase endoribonuclease 1α (IRE1α), a stress sensor and its reversion by using a selective inhibitor. Collectively, these results demonstrated that VCZ provokes endothelial dysfunction by oxidative stress involving eNOS/Nox4/IRE1α axis. The rapid exposure affected the endothelial function promoting eNOS uncoupling while a post-transcriptional modification, involving Nox4/IRE1α signaling, occurred following prolonged exposure. Thus, exposure to VCZ could contribute to the onset and/or progression of cardiovascular diseases associated with endothelial dysfunction.

Emerging Trends and Innovations in the Treatment and Diagnosis of Atherosclerosis and Cardiovascular Disease: A Comprehensive Review towards Healthier Aging

Cardiovascular diseases (CVDs) are classed as diseases of aging, which are associated with an increased prevalence of atherosclerotic lesion formation caused by such diseases and is considered as one of the leading causes of death globally, representing a severe health crisis affecting the heart and blood vessels. Atherosclerosis is described as a chronic condition that can lead to myocardial infarction, ischemic cardiomyopathy, stroke, and peripheral arterial disease and to date, most pharmacological therapies mainly aim to control risk factors in patients with cardiovascular disease. Advances in transformative therapies and imaging diagnostics agents could shape the clinical applications of such approaches, including nanomedicine, biomaterials, immunotherapy, cell therapy, and gene therapy, which are emerging and likely to significantly impact CVD management in the coming decade. This review summarizes the current anti-atherosclerotic therapies' major milestones, strengths, and limitations. It provides an overview of the recent discoveries and emerging technologies in nanomedicine, cell therapy, and gene and immune therapeutics that can revolutionize CVD clinical practice by steering it toward precision medicine. CVD-related clinical trials and promising pre-clinical strategies that would significantly impact patients with CVD are discussed. Here, we review these recent advances, highlighting key clinical opportunities in the rapidly emerging field of CVD medicine.

Clinical Performance and Persistence on Dual Pathway Inhibition with Rivaroxaban and Aspirin in Real-World Setting

ABSTRACT

The dual pathway inhibition (DPI) with low-dose rivaroxaban and aspirin in patients with stable atherosclerotic vascular disease reduces the occurrence of cardiovascular events, with no significant increase of intracranial or other critical organ bleedings. Our observational study aimed to describe the clinical performance, adherence, and persistence of DPI therapy among a real-world setting of patients with an established diagnosis of coronary artery (CAD) and/or peripheral artery disease (PAD). We prospectively included all consecutive patients with an established diagnosis of CAD and/or PAD treated with aspirin (ASA) 100 mg once daily and rivaroxaban 2.5 mg twice daily. Clinical evaluation was performed at baseline, before starting treatment, at 1 month, and every 6 months after the study drug administration. A total of 202 consecutive patients (mean age 66 ± 10 years; male 80%) eligible to DPI therapy were included. During a mean follow-up of 664 ± 177 days, the incidence rate of major bleedings and of major adverse cardiovascular events was 0.8 and 1.1 per 100 patients/year, respectively. The adherence to pharmacological treatment was 99%. Additionally, 13.4% of patients suspended the DPI therapy during the follow-up. Minor bleedings resulted the most common cause of both temporary and permanent DPI therapy discontinuation. This observational study supports the safety of DPI with low-dose rivaroxaban and aspirin among patients with CAD and PAD in a real-world setting, showing high persistence and maximum adherence to medical treatment.

Unlocking the link between haptoglobin polymorphism and noninfectious human diseases: insights and implications

Haptoglobin (Hp) is a polymorphic protein that was initially described as a hemoglobin (Hb)-binding protein. The major functions of Hp are to scavenge Hb, prevent iron loss, and prevent heme-based oxidation. Hp regulates angiogenesis, nitric oxide homeostasis, immune responses, and prostaglandin synthesis. Genetic polymorphisms in the Hp gene give rise to different phenotypes, including Hp 1-1, Hp 2-1, and Hp 2-2. Extensive research has been conducted to investigate the association between Hp polymorphisms and several medical conditions including cardiovascular disease, inflammatory bowel disease, cancer, transplantation, and hemoglobinopathies. Generally, the Hp 2-2 phenotype is associated with increased disease risk and poor outcomes. Over the years, the Hp 2 allele has spread under genetic pressures. Individuals with the Hp 2-2 phenotype generally exhibit lower levels of CD163 expression in macrophages. The decreased expression of CD163 may be associated with the poor antioxidant capacity in the serum of subjects carrying the Hp 2-2 phenotype. However, the Hp 1-1 phenotype may confer protection in some cases. The Hp1 allele has strong antioxidant, anti-inflammatory, and immunomodulatory properties. It is important to note that the benefits of the Hp1 allele may vary depending on genetic and environmental factors as well as the specific disease or condition under consideration. Therefore, the Hp1 allele may not necessarily confer advantages in all situations, and its effects may be context-dependent. This review highlights the current understanding of the role of Hp polymorphisms in cardiovascular disease, inflammatory bowel disease, cancer, transplantation, hemoglobinopathies, and polyuria.

Head-to-head ex vivo comparison of clinically used direct anticoagulant drugs

An imbalance in coagulation is associated with cardiovascular events. For prevention and treatment, anticoagulants, currently mainly xabans and gatrans, are used. The purpose of the present study was to provide a head-to-head comparison since there are no studies directly evaluating these novel anticoagulants. An additional aim was to find whether selected anthropological and biochemical factors can affect their anticoagulant properties as they are used in fixed doses. In this cross-sectional study, blood from 50 generally healthy donors was collected, and coagulation responses to dabigatran, argatroban, rivaroxaban, and apixaban, at a concentration of 1 μM, were analyzed. Heparin was used as a positive control. Prothrombin time (PT) expressed as international normalized ratio (INR) and activated partial thromboplastin time (aPTT) were measured and compared. Rivaroxaban was the most active according to PT/INR while argatroban according to aPTT. The ex vivo anticoagulant effect measured by INR correlated inversely with body mass index (BMI) in all four anticoagulants tested. Shortening of aPTT was associated with higher cholesterol and triglyceride levels. No sex-related differences were observed in response to the anticoagulant treatments. As this was an ex vivo study and pharmacokinetic factors were not included, the influence of BMI is of high therapeutic importance.

Daytime plasma cortisol and cortisol response to dexamethasone suppression are associated with a prothrombotic state in hypertension

Background and aims

A prothrombotic state was demonstrated in patients with Cushing's syndrome and is involved in the development and progression of cardiovascular and renal damage in hypertensive patients. This study was designed to examine the relationships between cortisol secretion and the hemostatic and fibrinolytic systems in hypertension.

Methods

In 149 middle-aged, nondiabetic, essential hypertensive patients free of cardiovascular and renal complications, we measured hemostatic markers that express the spontaneous activation of the coagulation and fibrinolytic systems and assessed daily cortisol levels (8 AM, 3 PM, 12 AM; area under the curve, AUC-cortisol) together with the cortisol response to dexamethasone overnight suppression (DST-cortisol).

Results

Plasma levels of D-dimer (D-dim), prothrombin fragment 1 + 2 (F1 + 2), and von Willebrand factor (vWF) were progressively and significantly higher across tertiles of AUC-cortisol and DST-cortisol, whereas no differences were observed in fibrinogen, tissue plasminogen activator, plasminogen activator inhibitor-1, antithrombin III, protein C, and protein S. D-dim, F1 + 2, and vWF were significantly and directly correlated with age and both AUC-cortisol and DST-cortisol. Multivariate regression analysis showed that both AUC-cortisol and DST-cortisol were related to plasma D-dim, F1 + 2, and vWF independently of age, body mass index, blood pressure, and renal function.

Conclusion

Greater daily cortisol profile and cortisol response to overnight suppression are independently associated with a prothrombotic state in hypertensive patients and might contribute to the development of organ damage and higher risk of cardiovascular complications.

Salvianolic acid B inhibits thrombosis and directly blocks the thrombin catalytic site

Background

Salvianolic acid B (SAB) is a major component of Salvia miltiorrhiza root (Danshen), widely used in East/Southeast Asia for centuries to treat cardiovascular diseases. Danshen depside salt, 85% of which is made up of SAB, is approved in China to treat chronic angina. Although clinical observations suggest that Danshen extracts inhibited arterial and venous thrombosis, the exact mechanism has not been adequately elucidated.

Objective

To delineate the antithrombotic mechanisms of SAB.

Methods

We applied platelet aggregation and coagulation assays, perfusion chambers, and intravital microscopy models. The inhibition kinetics and binding affinity of SAB to thrombin are measured by thrombin enzymatic assays, intrinsic fluorescence spectrophotometry, and isothermal titration calorimetry. We used molecular in silico docking models to predict the interactions of SAB with thrombin.

Results

SAB dose-dependently inhibited platelet activation and aggregation induced by thrombin. SAB also reduced platelet aggregation induced by adenosine diphosphate and collagen. SAB attenuated blood coagulation by modifying fibrin network structures and significantly decreased thrombus formation in mouse cremaster arterioles and perfusion chambers. The direct SAB-thrombin interaction was confirmed by enzymatic assays, intrinsic fluorescence spectrophotometry, and isothermal titration calorimetry. Interestingly, SAB shares key structural similarities with the trisubstituted benzimidazole class of thrombin inhibitors, such as dabigatran. Molecular docking models predicted the binding of SAB to the thrombin active site.

Conclusion

Our data established SAB as the first herb-derived direct thrombin catalytic site inhibitor, suppressing thrombosis through both thrombin-dependent and thrombin-independent pathways. Purified SAB may be a cost-effective agent for treating arterial and deep vein thrombosis.

Antiplatelet De-Escalation Strategies in Patients Undergoing Percutaneous Coronary Intervention

Dual antiplatelet therapy-the combination of aspirin and a P2Y12 inhibitor-remains the standard antiplatelet regimen recommended to prevent ischemic complications immediately after percutaneous coronary intervention. Nonetheless, recent advances in stent technologies, percutaneous coronary intervention techniques, adjunctive pharmacotherapy for secondary prevention, and the rising awareness of the prognostic impact of bleeding, which are inevitably associated with dual antiplatelet therapy, led to the investigation of alternative antiplatelet regimens related to fewer bleeding and a preserved ischemic protection. Thrombotic complications occur mostly in the first months after percutaneous coronary intervention, while the risk of bleeding remains stable over time; this observation laid the foundation of the concept of antiplatelet de-escalation, consisting of a more intense antiplatelet regimen early after percutaneous coronary intervention, followed by a less potent antiplatelet therapy thereafter. According to new definitions proposed by the Academic Research Consortium, de-escalation can be achieved by discontinuation of 1 antiplatelet agent, switching from a potent P2Y12 inhibitor to clopidogrel, or by reducing the dose of antiplatelet agents. This review discusses the rationale and the evidence supporting antiplatelet de-escalation, provides practical guidance to use these new regimens, and gives insights into future developments in the field.

Chemokine Fractalkine and Non-Obstructive Coronary Artery Disease-Is There a Link?

Non-obstructive coronary artery disease (NO-CAD) constitutes a heterogeneous group of conditions collectively characterized by less than 50% narrowing in at least one major coronary artery with a fractional flow reserve (FFR) of ≤0.80 observed in coronary angiography. The pathogenesis and progression of NO-CAD are still not fully understood, however, inflammatory processes, particularly atherosclerosis and microvascular dysfunction are known to play a major role in it. Chemokine fractalkine (FKN/CX3CL1) is inherently linked to these processes. FKN/CX3CL1 functions predominantly as a chemoattractant for immune cells, facilitating their transmigration through the vessel wall and inhibiting their apoptosis. Its concentrations correlate positively with major cardiovascular risk factors. Moreover, promising preliminary results have shown that FKN/CX3CL1 receptor inhibitor (KAND567) administered in the population of patients with ST-elevation myocardial infarction (STEMI) undergoing percutaneous coronary intervention (PCI), inhibits the adverse reaction of the immune system that causes hyperinflammation. Whereas the link between FKN/CX3CL1 and NO-CAD appears evident, further studies are necessary to unveil this complex relationship. In this review, we critically overview the current data on FKN/CX3CL1 in the context of NO-CAD and present the novel clinical implications of the unique structure and function of FKN/CX3CL1 as a compound which distinctively contributes to the pathomechanism of this condition.

Development and application of novel ELISA-based analytical tools for assessing nitroxidative distress biomarkers in ischemic stroke: implications for improved diagnosis and clinical management

Ischemic cerebrovascular accident (iCVA) is a public health issue, whose subjacent events involve the development of nitroxidative distress. Identifying biomarkers that assist in the diagnosis of this disease has clinically relevant implications. The aim of this study was to develop an analytic tool for measuring nitroxidative distress biomarkers, intended for application in clinical practice to enhance patient healthcare. Three enzyme linked immunosorbent assays (ELISA) were developed, with different detection objectives. One of them, in a sandwich format, quantifies the amount of fibrinogen in human plasma, an important glycoprotein involved in the blood coagulation process, contributing to thrombus formation and thereby participating in the mechanism of ischemic stroke. Another ELISA, also in a sandwich format, detects the presence of nitrotyrosine residues in fibrinogen from human plasma, a nitroxidative posttranslational modification resulting from the attack of peroxynitrite by-products on tyrosine residues present in proteins. The third one, in inhibition format, determines human plasma nitrotyrosine total content and was used to analyze human plasma samples from control and iCVA patients. Those two groups of plasma samples were analyzed using inhibition ELISA, revealing statistically significant differences in their nitrotyrosine content and molar ratios of nitrotyrosine to fibrinogen, which were higher in the iCVA group. This study provides evidence that nitroxidative distress occurs in ischemic stroke, as indicated by the detection of the biomarker nitrotyrosine. This finding supports other studies that also identified nitrotyrosine in ischemic stroke, through several different methods. This specific ELISA method is applicable for the rapid analysis of clinical samples, making it a potential clinical tool for assessing iCVA patients.

Mechanisms of endothelial activation, hypercoagulation and thrombosis in COVID-19: a link with diabetes mellitus

Early since the onset of the COVID-19 pandemic, the medical and scientific community were aware of extra respiratory actions of SARS-CoV-2 infection. Endothelitis, hypercoagulation, and hypofibrinolysis were identified in COVID-19 patients as subsequent responses of endothelial dysfunction. Activation of the endothelial barrier may increase the severity of the disease and contribute to long-COVID syndrome and post-COVID sequelae. Besides, it may cause alterations in primary, secondary, and tertiary hemostasis. Importantly, these responses have been highly decisive in the evolution of infected patients also diagnosed with diabetes mellitus (DM), who showed previous endothelial dysfunction. In this review, we provide an overview of the potential triggers of endothelial activation related to COVID-19 and COVID-19 under diabetic milieu. Several mechanisms are induced by both the viral particle itself and by the subsequent immune-defensive response (i.e., NF-κB/NLRP3 inflammasome pathway, vasoactive peptides, cytokine storm, NETosis, activation of the complement system). Alterations in coagulation mediators such as factor VIII, fibrin, tissue factor, the von Willebrand factor: ADAMST-13 ratio, and the kallikrein-kinin or plasminogen-plasmin systems have been reported. Moreover, an imbalance of thrombotic and thrombolytic (tPA, PAI-I, fibrinogen) factors favors hypercoagulation and hypofibrinolysis. In the context of DM, these mechanisms can be exacerbated leading to higher loss of hemostasis. However, a series of therapeutic strategies targeting the activated endothelium such as specific antibodies or inhibitors against thrombin, key cytokines, factor X, complement system, the kallikrein-kinin system or NETosis, might represent new opportunities to address this hypercoagulable state present in COVID-19 and DM. Antidiabetics may also ameliorate endothelial dysfunction, inflammation, and platelet aggregation. By improving the microvascular pathology in COVID-19 and post-COVID subjects, the associated comorbidities and the risk of mortality could be reduced.

Lymphocyte-related ratios in methamphetamine-induced psychotic disorder in Taiwan, comparing with patients with schizophrenia

The lymphocyte-related ratios, neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR) and platelet-to-lymphocyte ratio (PLR) are new measures of inflammation within the body. Few studies have investigated the inflammatory response of patients with methamphetamine-induced psychotic disorder. Clinically, the psychotic symptoms and behavioural manifestation of methamphetamine-induced psychotic disorder are often indistinguishable from paranoid schizophrenia. We aimed to determine the differences in these inflammatory markers between patients with methamphetamine-induced psychotic disorder, patients with schizophrenia and healthy individuals. A total of 905 individuals were recruited. The NLR and MLR were found to be higher in both patients with methamphetamine-induced psychotic disorders and patients with schizophrenia compared with healthy controls. There was no significant difference between the three groups in PLR. When compared with the control group, the methamphetamine-induced psychotic disorder group was significantly higher in NLR 27% (95%CI = 11 to 46%, p = 0.001), MLR 16% (95%CI = 3% to 31%, p = 0.013) and PLR 16% (95%CI = 5% to 28%, p = 0.005). NLR of the group with methamphetamine-induced psychotic disorder was 17% (95%CI = 73% to 94%, p = 0.004) less than the group with schizophrenia, while MLR and PLR did not differ significantly between the two groups. This is the first study that investigated the lymphocyte-related ratios in methamphetamine-induced psychotic disorder when compared with patients with schizophrenia and healthy individuals. The results showed that both patients with methamphetamine-induced psychotic disorder and patients with schizophrenia had stronger inflammatory responses than the healthy control. Our finding also indicated that the inflammatory response of methamphetamine-induced psychotic disorder was between those of patients with schizophrenia and healthy individuals.

The Role of Tissue Factor In Signaling Pathways of Pathological Conditions and Angiogenesis

Tissue factor (TF) is an integral transmembrane protein associated with the extrinsic coagulation pathway. TF gene expression is regulated in response to inflammatory cytokines, bacterial lipopolysaccharides, and mechanical injuries. TF activity may be affected by phosphorylation of its cytoplasmic domain and alternative splicing. TF acts as the primary initiator of physiological hemostasis, which prevents local bleeding at the injury site. However, aberrant expression of TF, accompanied by the severity of diseases and infections under various pathological conditions, triggers multiple signaling pathways that support thrombosis, angiogenesis, inflammation, and metastasis. Protease-activated receptors (PARs) are central in the downstream signaling pathways of TF. In this study, we have reviewed the TF signaling pathways in different pathological conditions, such as wound injury, asthma, cardiovascular diseases (CVDs), viral infections, cancer and pathological angiogenesis. Angiogenic activities of TF are critical in the repair of wound injuries and aggressive behavior of tumors, which are mainly performed by the actions of vascular endothelial growth factor (VEGF) and hypoxia-inducible factor-1 (HIF1-α). Pro-inflammatory effects of TF have been reported in asthma, CVDs and viral infections, including COVID-19, which result in tissue hypertrophy, inflammation, and thrombosis. TF-FVII induces angiogenesis via clotting-dependent and -independent mechanisms. Clottingdependent angiogenesis is induced via the generation of thrombin and cross-linked fibrin network, which facilitate vessel infiltration and also act as a reservoir for endothelial cells (ECs) growth factors. Expression of TF in tumor cells and ECs triggers clotting-independent angiogenesis through induction of VEGF, urokinase-type plasminogen activator (uPAR), early growth response 1 (EGR1), IL8, and cysteine-rich angiogenic inducer 61 (Cyr61).

The protective effects of empagliflozin on DNA oxidative changes in a model of vascular endothelial and smooth muscle cells damaged by oxidized cholesterol

BACKGROUND

Diabetes patients often suffer chronic vascular complications resulting from endothelial dysfunction, smooth muscle cell (SMC) proliferation, inflammation and disturbed oxidative balance. Empagliflozin is one of three approved sodium-glucose cotransporter 2 (SGLT2) inhibitors for type 2 diabetes mellitus.

THE AIM OF THIS STUDY

was to determine the protective and repairing effect of EMPA in a model of vascular endothelial and SMC damage with 25-hydroxycholesterol (25-OHC).

METHODS

Human umbilical vascular endothelial cells (HUVECs) and SMCs were treated with compounds which induce DNA single-strand breaks (SSBs) and subjected to comet assay. Oxidative DNA damage was detected using endonuclease III (Nth) or human 8 oxoguanine DNA glycosylase (hOOG1). Reactive oxygen species (ROS) formation was determined by the fluorescence of a 6-carboxy-2',7'-dichlorodihydrofluoresce probe in diacetate (H2DCFDA).

RESULTS

25-OHC-stimulated SMCs showed greater resistance to ROS generation and DNA damage compared to HUVECs. In both experimental models, EMPA treatment was associated with lower ROS production and DNA damage, including oxidative damage to purines and pyrimidines. This effect was not dose-dependent. EMPA was found to counteract this DNA damage by inhibiting ROS production.

CONCLUSIONS

It appears that the EMPA induced indirect repair of DNA by inhibiting ROS production.

Clinically Driven Revascularization in High-Risk Patients Treated With Ticagrelor Monotherapy After PCI: Insights from the Randomized TWILIGHT Trial

Repeat coronary revascularization is a common adverse event after successful percutaneous coronary intervention. This analysis aimed to assess the effects of ticagrelor monotherapy on repeat clinically driven revascularization (CDR). In the TWILIGHT (Ticagrelor With Aspirin or Alone in High-Risk Patients after Coronary Intervention) trial, after 3 months of ticagrelor plus aspirin, high-risk patients were maintained on ticagrelor and randomly allocated to aspirin or placebo for 1 year. The primary end point of this analysis was CDR within 12 months after randomization. The key secondary end points were major adverse cardiovascular and cerebrovascular events (MACCEs), a composite of all-cause death, myocardial infarction, stroke, or CDR, and net adverse clinical events (NACEs), including the individual components of MACCEs and clinically relevant bleeding. The analysis was performed in the per-protocol population. CDR occurred in 473 of 7,039 patients and was associated with a significantly higher risk of subsequent all-cause death, myocardial infarction, or stroke (adjusted hazard ratios [HRs] 2.92, 95% confidence interval [CI] 1.82 to 4.67). Ticagrelor monotherapy was associated with a similar 12-month risk of CDR (7.1% vs 6.6%; HR 1.09, 95% CI 0.90 to 1.30, p = 0.363) and MACCEs (8.9% vs 8.6%; HR 1.04, 95% CI 0.89 to 1.22, p = 0.619), and a lower risk of NACEs (12.2% vs 14.6%; HR 0.83 95% CI 0.73 to 0.94, p = 0.004) than ticagrelor plus aspirin. In conclusion, among high-risk patients who underwent percutaneous coronary intervention, ticagrelor monotherapy after 3 months of ticagrelor-based dual antiplatelet therapy was associated with a similar risk of CDR and MACCEs and a decrease of NACEs (TWILIGHT: NCT02270242).

Crucial roles of red blood cells and platelets in whole blood thrombin generation

Red blood cells (RBCs) and platelets contribute to the coagulation capacity in bleeding and thrombotic disorders. The thrombin generation (TG) process is considered to reflect the interactions between plasma coagulation and the various blood cells. Using a new high-throughput method capturing the complete TG curve, we were able to compare TG in whole blood and autologous platelet-rich and platelet-poor plasma to redefine the blood cell contributions to the clotting process. We report a faster and initially higher generation of thrombin and shorter coagulation time in whole blood than in platelet-rich plasma upon low concentrations of coagulant triggers, including tissue factor, Russell viper venom factor X, factor Xa, factor XIa, and thrombin. The TG was accelerated with increased hematocrit and delayed after prior treatment of RBC with phosphatidylserine-blocking annexin A5. RBC treatment with ionomycin increased phosphatidylserine exposure, confirmed by flow cytometry, and increased the TG process. In reconstituted blood samples, the prior selective blockage of phosphatidylserine on RBC with annexin A5 enhanced glycoprotein VI-induced platelet procoagulant activity. For patients with anemia or erythrocytosis, cluster analysis revealed high or low whole-blood TG profiles in specific cases of anemia. The TG profiles lowered upon annexin A5 addition in the presence of RBCs and thus were determined by the extent of phosphatidylserine exposure of blood cells. Profiles for patients with polycythemia vera undergoing treatment were similar to that of control subjects. We concluded that RBC and platelets, in a phosphatidylserine-dependent way, contribute to the TG process. Determination of the whole-blood hypo- or hyper-coagulant activity may help to characterize a bleeding or thrombosis risk.

Rivaroxaban plus aspirin vs. dual antiplatelet therapy in endovascular treatment in peripheral artery disease and analysis of medication utilization of different lesioned vascular regions

Background

In the management of Peripheral Arterial Disease (PAD), the administration of anticoagulant or antiplatelet agents is imperative. The use of Dual Antiplatelet Therapy (DAPT) in conjunction with rivaroxaban has shown potential in mitigating adverse outcomes. Given the heterogeneity in the pathology of lower limb arteries, there is a compelling case for individualized treatment strategies.

Methods

In a single-center retrospective study on pharmacotherapy for peripheral artery disease, patients were treated with either aspirin combined with rivaroxaban or aspirin coupled with clopidogrel. The primary efficacy outcome encompassed a composite of increases in the Rutherford classification, acute limb ischemia, amputations due to vascular causes, target lesion revascularization, myocardial infarction, ischemic stroke, and cardiovascular death. The primary safety outcome was major bleeding, as defined by the Thrombolysis in Myocardial Infarction (TIMI) criteria; meanwhile, major bleeding as categorized by the International Society on Thrombosis and Haemostasis (ISTH) served as a secondary safety outcome. The study differentiated between two subgroups: patients with only above-the-knee and below-the-knee arterial lesions.

Results

From January 2016 to December 2021, 455 patients received either clopidogrel plus aspirin or rivaroxaban plus aspirin following endovascular treatment (EVT). The rivaroxaban group (n = 220) exhibited a lower incidence of primary efficacy outcomes [49.1% vs. 60.4%, hazard ratio (HR) 0.77, P = 0.006] but had more TIMI major bleeding events (5.9% vs. 2.1%, HR 2.6, P = 0.04). ISTH major bleeding events did not show a significant difference, though a higher percentage of rivaroxaban patients discontinued medication due to bleeding (10% vs. 4.7%, HR 2.2, P = 0.03). In the above-the-knee arterial disease subgroup, the rivaroxaban group demonstrated a lower incidence of primary efficacy outcomes (28.2% vs. 45.2%, HR 0.55, P = 0.02). In the below-the-knee arterial disease subgroup, no significant difference was observed in the occurrence of primary efficacy events between the two groups (58.7% vs. 64.8%, HR 0.76, P = 0.14).

Conclusion

Rivaroxaban plus aspirin improved outcomes compared to DAPT in patients with lower extremity artery disease. Similar findings were observed in the above-the-knee artery lesion-only group. However, in the below-the-knee artery lesion-only group, rivaroxaban plus aspirin did not surpass DAPT in efficacy. Regarding safety, rivaroxaban plus aspirin exhibited higher bleeding risks and more frequent treatment discontinuation than aspirin combined with clopidogrel.

Endothelial cell dysfunction in cardiac disease: driver or consequence?

The vascular endothelium is a multifunctional cellular system which directly influences blood components and cells within the vessel wall in a given tissue. Importantly, this cellular interface undergoes critical phenotypic changes in response to various biochemical and hemodynamic stimuli, driving several developmental and pathophysiological processes. Multiple studies have indicated a central role of the endothelium in the initiation, progression, and clinical outcomes of cardiac disease. In this review we synthesize the current understanding of endothelial function and dysfunction as mediators of the cardiomyocyte phenotype in the setting of distinct cardiac pathologies; outline existing in vivo and in vitro models where key features of endothelial cell dysfunction can be recapitulated; and discuss future directions for development of endothelium-targeted therapeutics for cardiac diseases with limited existing treatment options.

The accumulation of erythrocytes quantified and visualized by Glycophorin C in carotid atherosclerotic plaque reflects intraplaque hemorrhage and pre-procedural neurological symptoms

The accumulation of erythrocyte membranes within an atherosclerotic plaque may contribute to the deposition of free cholesterol and thereby the enlargement of the necrotic core. Erythrocyte membranes can be visualized and quantified in the plaque by immunostaining for the erythrocyte marker glycophorin C. Hence, we theorized that the accumulation of erythrocytes quantified by glycophorin C could function as a marker for plaque vulnerability, possibly reflecting intraplaque hemorrhage (IPH), and offering predictive value for pre-procedural neurological symptoms. We employed the CellProfiler-integrated slideToolKit workflow to visualize and quantify glycophorin C, defined as the total plaque area that is positive for glycophorin C, in single slides of culprit lesions obtained from the Athero-Express Biobank of 1819 consecutive asymptomatic and symptomatic patients who underwent carotid endarterectomy. Our assessment included the evaluation of various parameters such as lipid core, calcifications, collagen content, SMC content, and macrophage burden. These parameters were evaluated using a semi-quantitative scoring method, and the resulting data was dichotomized as predefined criteria into categories of no/minor or moderate/heavy staining. In addition, the presence or absence of IPH was also scored. The prevalence of IPH and pre-procedural neurological symptoms were 62.4% and 87.1%, respectively. The amount of glycophorin staining was significantly higher in samples from men compared to samples of women (median 7.15 (IQR:3.37, 13.41) versus median 4.06 (IQR:1.98, 8.32), p < 0.001). Glycophorin C was associated with IPH adjusted for clinical confounders (OR 1.90; 95% CI 1.63, 2.21; p =  < 0.001). Glycophorin C was significantly associated with ipsilateral pre-procedural neurological symptoms (OR:1.27, 95%CI:1.06-1.41, p = 0.005). Sex-stratified analysis, showed that this was also the case for men (OR 1.37; 95%CI 1.12, 1.69; p = 0.003), but not for women (OR 1.15; 95%CI 0.77, 1.73; p = 0.27). Glycophorin C was associated with classical features of a vulnerable plaque, such as a larger lipid core, a higher macrophage burden, less calcifications, a lower collagen and SMC content. There were marked sex differences, in men, glycophorin C was associated with calcifications and collagen while these associations were not found in women. To conclude, the accumulation of erythrocytes in atherosclerotic plaque quantified and visualized by glycophorin C was independently associated with the presence of IPH, preprocedural symptoms in men, and with a more vulnerable plaque composition in both men and women. These results strengthen the notion that the accumulation of erythrocytes quantified by glycophorin C can be used as a marker for plaque vulnerability.

Diabetes- versus smoking-related thrombo-inflammation in peripheral artery disease

Peripheral artery disease (PAD) is a major health problem with increased cardiovascular mortality, morbidity and disabling critical limb threatening ischemia (CLTI) and amputation. Diabetes mellitus (DM) and cigarette smoke are the main risk factors for the development of PAD. Although diabetes related PAD shows an accelerated course with worse outcome regarding complications, mortality and amputations compared with non-diabetic patients, current medical treatment does not make this distinction and includes standard antiplatelet and lipid lowering drugs for all patients with PAD. In this review we discuss the pathophysiologic mechanisms of PAD, with focus on differences in thrombo-inflammatory processes between diabetes-related and smoking-related PAD, and hypothesize on possible mechanisms for the progressive course of PAD in DM. Furthermore, we comment on current medical treatment and speculate on alternative medical drug options for patients with PAD and DM.

Elevated factor XIa as a modulator of plasma fibrin clot properties in coronary artery disease

INTRODUCTION

Patients with coronary artery disease (CAD) display a prothrombotic fibrin clot phenotype, involving low permeability and resistance to lysis. The determinants of this phenotype remain elusive. Circulating tissue factor (TF) and activated factor XI (FXIa) are linked to arterial thromboembolism. We investigated whether detectable active TF and FXIa influence fibrin clot properties in CAD.

METHODS

In 118 CAD patients (median age 65 years, 78% men), we assessed Ks, an indicator of clot permeability, and clot lysis time (CLT) in plasma-based assays, along with the presence of active TF and FXIa. We also analysed proteins involved in clotting and thrombolysis, including fibrinogen, plasminogen activator inhibitor-1 (PAI-1) and thrombin activatable thrombolysis inhibitor (TAFI). During a median 106 month (interquartile range 95-119) follow-up, myocardial infarction (MI), stroke, systemic thromboembolism (SE) and cardiovascular (CV) death were recorded.

RESULTS

Circulating TF and FXIa, detected in 20.3% and 39.8% of patients, respectively, were associated with low Ks and prolonged CLT. Solely FXIa remained an independent predictor of low Ks and high CLT on multivariable analysis. Additionally, fibrinogen and PAI-1 were associated with low Ks, while PAI-1 and TAFI-with prolonged CLT. During follow-up low Ks and prolonged CLT increased the risk of MI and the latter also a composite endpoint of MI, stroke/SE or CV death.

CONCLUSIONS

To our knowledge, this study is the first to show that circulating FXIa is associated with prothrombotic fibrin clot properties in CAD, suggesting additional mechanisms through which FXIa inhibitors could act as novel antithrombotic agents in CAD.

The Effects of Cardiac Rehabilitation including Nordic Walking in Patients with Chronic Coronary Syndromes after Percutaneous Coronary Interventions in Elective Mode

Background: Percutaneous coronary intervention (PCI) in patients with chronic coronary syndrome (CCS) is a worldwide method of coronary revascularisation. The aim of this study was to assess the immediate and long-term effects of Nordic Walking (NW) training added to a standard cardiac rehabilitation programme on physical activity (PA) and capacity and life quality, as well as selected proatherogenic risk factors. Methods: The studied group comprised 50 patients (considering exclusion criteria, 40 patients), aged 56-70, with CCS after elective PCI qualified them for a 6-weeks-long cardiac rehabilitation. The follow-up period lasted 4 months, and control visits occurred at 2 and 4 months. The studied patients were randomly divided into two groups: control group-standard cardiac rehabilitation programme and experimental group-standard cardiac rehabilitation programme additionally combined with NW training. Results: The cardiac rehabilitation programme in the experimental, compared to the control group, increased intense PA (from 731.43 ± 909.9 to 2740 ± 2875.96 vs. from 211.43 ± 259.43 to 582.86 ± 1289.74 MET min/week) and aerobic efficiency-VO2peak (from 8.67 ± 0.88 to 9.96 ± 1.35 vs. from 7.39 ± 2 to 7.41 ± 2.46 METs), as well as quality of life according to the WHOQOL-BREF questionnaire (from 3.57 ± 0.51 to 4.14 ± 0.36 vs. from 3.29 ± 0.47 to 3.57 ± 0.51 points). The walking distance assessed with the 6-min walk test did not differ between the groups before the beginning of the rehabilitation programme. Both at the I follow-up and II follow-up time points, a significant increase in the walking distance was noted in the control and experimental groups compared to baseline, and the difference between both groups was significant at the end of follow-up (378.57 ± 71.35 vs. 469.29 ± 58.07, p = 0.003). Moreover, NW had a positive effect on the modulation within selected biochemical risk factors of atherosclerosis, as well as subjective quality of life and well-being. Conclusions: Introducing NW training into the cardiac rehabilitation process proved to be a more effective form of therapy in patients with CCS treated via PCI, as compared to the standard cardiac rehabilitation programme alone.

Elevated plasma factor XI predicts cardiovascular events in patients with type 2 diabetes: a long-term observational study

BACKGROUND

Type 2 diabetes mellitus (T2DM) patients are at high risk of cardiovascular (CV) events. Factor XI (FXI) is associated with arterial thromboembolism, including myocardial infarction (MI), stroke, and CV mortality. The role of FXI in T2DM is unknown. We investigated whether plasma FXI is associated with CV events in T2DM patients in long-term observation.

METHODS

In 133 T2DM patients (aged 66 ± 8 years, 40.6% women, median T2DM duration 5 [2-10] years) we assessed plasma FXI levels, along with fibrin clot properties, thrombin generation, and fibrinolysis proteins. A composite endpoint of MI, stroke, or CV death, as well as CV mortality alone were assessed during a median follow-up of 72 months.

RESULTS

Plasma FXI above the 120% upper normal limit was detected in 25 (18.8%) patients and showed positive association with LDL cholesterol and thrombin activatable fibrinolysis inhibitor, but not glycated hemoglobin, inflammatory markers or thrombin generation. The composite endpoint (n = 21, 15.8%) and CV death alone (n = 16, 12%) were more common in patients with elevated FXI (hazard ratio [HR] 10.94, 95% confidence interval [CI] 4.46-26.87, p < 0.001 and HR 7.11, 95% CI 2.61-19.31, p < 0.001, respectively). On multivariable analysis, FXI remained an independent predictor of the composite endpoint and CV death, regardless of concomitant coronary artery disease.

CONCLUSIONS

To our knowledge, this study is the first to show that in T2DM patients, elevated FXI could predict major CV events, including mortality, which suggest that anti-FXI agents might be a potential novel antithrombotic option in this disease.

Post-transcriptional control of haemostatic genes: mechanisms and emerging therapeutic concepts in thrombo-inflammatory disorders

The haemostatic system is pivotal to maintaining vascular integrity. Multiple components involved in blood coagulation have central functions in inflammation and immunity. A derailed haemostasis is common in prevalent pathologies such as sepsis, cardiovascular disorders, and lately, COVID-19. Physiological mechanisms limit the deleterious consequences of a hyperactivated haemostatic system through adaptive changes in gene expression. While this is mainly regulated at the level of transcription, co- and posttranscriptional mechanisms are increasingly perceived as central hubs governing multiple facets of the haemostatic system. This layer of regulation modulates the biogenesis of haemostatic components, for example in situations of increased turnover and demand. However, they can also be 'hijacked' in disease processes, thereby perpetuating and even causally entertaining associated pathologies. This review summarizes examples and emerging concepts that illustrate the importance of posttranscriptional mechanisms in haemostatic control and crosstalk with the immune system. It also discusses how such regulatory principles can be used to usher in new therapeutic concepts to combat global medical threats such as sepsis or cardiovascular disorders.

Bleeding Control in Advanced Gastric Cancer; Role of Radiotherapy

Objectives

The aim of our study is to see the efficacy of palliative radiotherapy (RT) for bleeding control in patients with advanced gastric cancer (AGC).

Materials and Methods

It is a retrospective review based on observations of 74 AGC patients with a median age of 60 years (range 50-82 years) who had active tumour bleeding and were treated with palliative RT. Treatment response was assessed by both subjective symptom relief and objective change in parameters. Objective response to RT was defined by an increase in the median haemoglobin (Hb) level of patients and a decrease in number of packed red blood cell (RBC) units needed by patients after RT.

Results

Response to haemostatic RT was observed in 52 patients out of 74 patients (70.27%). We observed a significant increase in mean Hb level after palliative RT. Pre-RT mean Hb was 6.14 ± 1.01 and post-RT mean Hb was 7.19 ± 1.75 (P < 0.05). Response to RT was also evident in a significant decrease in the number of packed RBC units post-haemostatic RT. The mean number of pre-RT transfused packed RBC units was 8.28 ± 3.76 and post-RT, it was 4.34 ± 2.91 (P < 0.05). The median overall survival was 90 days and the median transfusion-free survival was 40 days.

Conclusion

RT may be an effective treatment option for bleeding control in AGC. In our study, we observed fair and reasonably durable haemostasis. A success rate of 70.24% was documented with clinical palliation, a higher Hb level and fewer transfusions after RT. This modality for bleeding control is more important and reliable in situations where alternative modalities are not feasible.

Association of sex and cardiovascular risk factors with atherosclerosis distribution pattern in lower extremity peripheral artery disease

Objective

Atherosclerosis expression varies across not only coronary, cerebrovascular, and peripheral arteries but also within the peripheral vascular tree. The underlying pathomechanisms of distinct atherosclerosis phenotypes in lower extremity peripheral artery disease (PAD) is poorly understood. We investigated the association of cardiovascular risk factors (CVRFs) and atherosclerosis distribution in a targeted approach analyzing symptomatic patients with isolated anatomic phenotypes of PAD.

Methods

In a cross-sectional analysis of consecutive patients undergoing first-time endovascular recanalization for symptomatic PAD, data of patients with isolated anatomic phenotypes of either proximal (iliac) or distal (infrageniculate) atherosclerosis segregation were extracted. We performed a multivariable logistic regression model with backward elimination to investigate the association of proximal and distal PAD with CVRFs.

Results

Of the 637 patients (29% females) with endovascular recanalization, 351 (55%) had proximal and 286 (45%) had distal atherosclerosis. Female sex [odds ratio (OR) 0.33, 95% confidence interval (CI) 0.20-0.54, p = 0.01], active smoking (OR 0.16, 95% CI 0.09-0.28, p < 0.001), and former smoking (OR 0.33, 95% CI 0.20-0.57, p < 0.001) were associated with proximal disease. Diabetes mellitus (DM) (OR 3.25, 95% CI 1.93-5.46, p < 0.001), chronic kidney disease (CKD) (OR 1.18, 95% CI 1.08-1.28, p < 0.001), and older age (OR 1.31, 95% CI 1.06-1.61, p = 0.01) were associated with distal disease.

Conclusion

Female sex, particularly in the context of smoking, is associated with clinically relevant, proximal atherosclerosis expression. Our additional findings that distal atherosclerosis expression is associated with DM, CKD, and older age suggest that PAD has at least two distinct atherosclerotic phenotypes with sex-specific and individual susceptibility to atherogenic risk factors.

Thrombin, a Key Driver of Pathological Inflammation in the Brain

Neurodegenerative diseases, including Alzheimer's disease (AD), are major contributors to death and disability worldwide. A multitude of evidence suggests that neuroinflammation is critical in neurodegenerative disease processes. Exploring the key mediators of neuroinflammation in AD, a prototypical neurodegenerative disease, could help identify pathologic inflammatory mediators and mechanisms in other neurodegenerative diseases. Elevated levels of the multifunctional inflammatory protein thrombin are commonly found in conditions that increase AD risk, including diabetes, atherosclerosis, and traumatic brain injury. Thrombin, a main driver of the coagulation cascade, has been identified as important to pathological events in AD and other neurodegenerative diseases. Furthermore, recent evidence suggests that coagulation cascade-associated proteins act as drivers of inflammation in the AD brain, and studies in both human populations and animal models support the view that abnormalities in thrombin generation promote AD pathology. Thrombin drives neuroinflammation through its pro-inflammatory activation of microglia, astrocytes, and endothelial cells. Due to the wide-ranging pro-inflammatory effects of thrombin in the brain, inhibiting thrombin could be an effective strategy for interrupting the inflammatory cascade which contributes to neurodegenerative disease progression and, as such, may be a potential therapeutic target for AD and other neurodegenerative diseases.

Emerging roles of protease-activated receptors in cardiometabolic disorders

Cardiometabolic disorders, including obesity-related insulin resistance and atherosclerosis, share sterile chronic inflammation as a major cause; however, the precise underlying mechanisms of chronic inflammation in cardiometabolic disorders are not fully understood. Accumulating evidence suggests that several coagulation proteases, including thrombin and activated factor X (FXa), play an important role not only in the coagulation cascade but also in the proinflammatory responses through protease-activated receptors (PARs) in many cell types. Four members of the PAR family have been cloned (PAR 1-4). For instance, thrombin activates PAR-1, PAR-3, and PAR-4. FXa activates both PAR-1 and PAR-2, while it has no effect on PAR-3 or PAR-4. Previous studies demonstrated that PAR-1 and PAR-2 activated by thrombin or FXa promote gene expression of inflammatory molecules mainly via the NF-κB and ERK1/2 pathways. In obese adipose tissue and atherosclerotic vascular tissue, various stresses increase the expression of tissue factor and procoagulant activity. Recent studies indicated that the activation of PARs in adipocytes and vascular cells by coagulation proteases promotes inflammation in these tissues, which leads to the development of cardiometabolic diseases. This review briefly summarizes the role of PARs and coagulation proteases in the pathogenesis of inflammatory diseases and describes recent findings (including ours) on the potential participation of this system in the development of cardiometabolic disorders. New insights into PARs may ensure a better understanding of cardiometabolic disorders and suggest new therapeutic options for these major health threats.

Fibrin clot properties in cardiovascular disease: from basic mechanisms to clinical practice

Fibrinogen conversion into insoluble fibrin and the formation of a stable clot is the final step of the coagulation cascade. Fibrin clot porosity and its susceptibility to plasmin-mediated lysis are the key fibrin measures, describing the properties of clots prepared ex vivo from citrated plasma. Cardiovascular disease (CVD), referring to coronary heart disease, heart failure, stroke, and hypertension, has been shown to be associated with the formation of dense fibrin networks that are relatively resistant to lysis. Denser fibrin mesh characterized acute patients at the onset of myocardial infarction or ischaemic stroke, while hypofibrinolysis has been identified as a persistent fibrin feature in patients following thrombotic events or in those with stable coronary artery disease. Traditional cardiovascular risk factors, such as smoking, diabetes mellitus, hyperlipidaemia, obesity, and hypertension, have also been linked with unfavourably altered fibrin clot properties, while some lifestyle modifications and pharmacological treatment, in particular statins and anticoagulants, may improve fibrin structure and function. Prospective studies have suggested that prothrombotic fibrin clot phenotype can predict cardiovascular events in short- and long-term follow-ups. Mutations and splice variants of the fibrinogen molecule that have been proved to be associated with thrombophilia or increased cardiovascular risk, along with fibrinogen post-translational modifications, prothrombotic state, inflammation, platelet activation, and neutrophil extracellular traps formation, contribute also to prothrombotic fibrin clot phenotype. Moreover, about 500 clot-bound proteins have been identified within plasma fibrin clots, including fibronectin, α2-antiplasmin, factor XIII, complement component C3, and histidine-rich glycoprotein. This review summarizes the current knowledge on the mechanisms underlying unfavourable fibrin clot properties and their implications in CVD and its thrombo-embolic manifestations.

Procoagulant factors and future risk of arterial cardiovascular disease in patients with prior venous thrombosis: A cohort study

Patients with venous thrombosis (VT) are at increased risk of future arterial cardiovascular disease (CVD) (i.e., myocardial infarction, ischemic stroke or peripheral artery disease). We investigated whether shared risk factors for VT and CVD are associated with the levels of procoagulant factors (fibrinogen, factor VIII, and von Willebrand factor), and whether the relationship between these risk factors and subsequent CVD was mediated through these procoagulant factors in patients with VT. In a follow-up study consisting of 4956 patients with VT, 2176 patients (44%) provided blood samples and were linked to the Dutch Hospital registry of Statistics Netherlands to identify hospital admissions or procedures for subsequent CVD. In total, 52 CVD events occurred over a follow-up of 11,124 years, with an incidence rate of 4.7 per 1000 patient years (95% confidence intervals 3.5-6.1). Increasing age, male sex, smoking history, major illnesses, dyslipidemia, and impaired fasting glucose levels were associated with increased CVD risk. Procoagulant factor levels were also associated with CVD risk. When adjusted for these procoagulant factors, the association between the risk factors and CVD attenuated partially. This study provides evidence that procoagulant factors can partially explain the association between increased risks of subsequent CVD in patients with previous VT.

The complement alternative pathway and hemostasis

The complement and hemostatic systems are complex systems, and both involve enzymatic cascades, regulators, and cell components-platelets, endothelial cells, and immune cells. The two systems are ancestrally related and are defense mechanisms that limit infection by pathogens and halt bleeding at the site of vascular injury. Recent research has uncovered multiple functional interactions between complement and hemostasis. On one side, there are proteins considered as complement factors that activate hemostasis, and on the other side, there are coagulation proteins that modulate complement. In addition, complement and coagulation and their regulatory proteins strongly interact each other to modulate endothelial, platelet and leukocyte function and phenotype, creating a potentially devastating amplifying system that must be closely regulated to avoid unwanted damage and\or disseminated thrombosis. In view of its ability to amplify all complement activity through the C3b-dependent amplification loop, the alternative pathway of complement may play a crucial role in this context. In this review, we will focus on available and emerging evidence on the role of the alternative pathway of complement in regulating hemostasis and vice-versa, and on how dysregulation of either system can lead to severe thromboinflammatory events.

Activated factor XI is associated with increased factor VIIa - Antithrombin complexes in stable coronary artery disease: Impact on cardiovascular outcomes

BACKGROUND

Coronary artery disease (CAD) is associated with a prothrombotic tendency including increased factor (F) VIIa-antithrombin (FVIIa-AT) complexes, a measure of tissue factor (TF) exposure, and activated FXI (FXIa). We investigated whether increased FVIIa-AT complexes are associated with FXIa and active TF and if major adverse clinical outcomes are predicted by the complexes in CAD.

METHODS

In 120 CAD patients, we assessed FVIIa-AT complex concentrations and the presence of circulating FXIa and active TF. Levels of 8-iso-prostaglandin F2α (8-iso-PGF2α), interleukin-6, high-sensitivity C reactive protein, prothrombin fragment 1 + 2, and free Tissue Factor Pathway Inhibitor were determined. Myocardial infarction (MI), ischemic stroke, systemic thromboembolism (SE), and cardiovascular (CV) death were recorded separately and as a composite endpoint, during follow-up.

RESULTS

FVIIa-AT complexes were positively associated with current smoking and multivessel CAD. Elevated FVIIa-AT complexes characterized patients with circulating FXIa and/or active TF in association with increased plasma isoprostanes but not with thrombin generation or inflammatory markers. During a median follow-up of 106 months (interquartile range 95-119), high baseline levels of FVIIa-AT complexes predicted ischemic stroke/SE (HR 4.61 [95% CI 1.48-18.42]) and a composite endpoint of MI, stroke/SE, and CV death (HR 7.47 [95% CI 2.81-19.87]).

CONCLUSIONS

This study is the first to show that high FVIIa-AT complexes characterize advanced CAD patients with detectable FXIa and active TF, which is, in part, driven by oxidative stress. High FVIIa-AT complexes were associated with the risk of ischemic stroke/SE during long-term follow-up, highlighting the need for effective antithrombotic agents in CAD.

Integrating Mechanisms in Thrombotic Peripheral Arterial Disease

Peripheral arterial disease (PAD), a manifestation of systemic atherosclerosis, is underdiagnosed in the general population. Despite the extensive research performed to unravel its pathophysiology, inadequate knowledge exists, thus preventing the development of new treatments. This review aims to highlight the essential elements of atherosclerosis contributing to the pathophysiology of PAD. Furthermore, emphasis will be placed on the role of thrombo-inflammation, with particular focus on platelet and coagulation activation as well as cell-cell interactions. Additional insight will be then discussed to reveal the contribution of hypercoagulability to the development of vascular diseases such as PAD. Lastly, the current antithrombotic treatments will be discussed, and light will be shed on promising new targets aiming to aid the development of new treatments.

Inflammatory cytokines induce neutrophil extracellular traps interaction with activated platelets and endothelial cells exacerbate coagulation in moderate and severe essential hypertension

BACKGROUND

Essential hypertension (EH) patients suffer from paradoxically thrombotic rather than haemorrhagic, although the exact mechanism remains elusive. Our aim is to explore whether and how neutrophil extracellular traps (NETs) play the procoagulant role in EH patients, as well as evaluated whether the NET releasing were triggered by inflammatory cytokines.

METHODS

The concentration of plasma NETs components were detected by ELISA. The morphology of cells and NETs formation were analysed using immunofluorescence. Procoagulant activity was analysed by clotting time, purified coagulation complex and fibrin generation assays. Phosphatidylserine (PS) exposure on endothelial cells (ECs) was analysed with flow cytometry.

RESULTS

Moderate to severe EH patients plasma NETs levels were significantly higher compared to mild EH patients or controls. Furthermore, inflammatory cytokines can induce NETs generation, depleting these patients plasma inflammatory cytokines led to a reduction in NET releasing. NETs from moderate to severe EH patients neutrophils led to significantly decreased clotting time (CT), increased potency to generate thrombin and fibrin (all P  < 0.05). These procoagulant effects were markedly attenuated by approximately 70% using DNase I. Additionally, high concentrations NETs exerted a strong cytotoxic effect on ECs, conferring them a procoagulant phenotype.

CONCLUSION

Our study reveals that EH drives a systemic inflammatory environment, which, in turn, drives neutrophils to prime and NET releasing, and found a link between hypercoagulability and NETs levels in moderate to severe EH patients. Therefore, anti-inflammatory combined with block the generation of NETs may represent a new therapeutic target for preventing thrombosis in EH patients.

Regulation of VWF (Von Willebrand Factor) in Inflammatory Thrombosis

Increasing evidence indicates that inflammation promotes thrombosis via a VWF (von Willebrand factor)-mediated mechanism. VWF plays an essential role in maintaining the balance between blood coagulation and bleeding, and inflammation can lead to aberrant regulation. VWF is regulated on a transcriptional and (post-)translational level, and its secretion into the circulation captures platelets upon endothelial activation. The significant progress that has been made in understanding transcriptional and translational regulation of VWF is described in this review. First, we describe how VWF is regulated at the transcriptional and post-translational level with a specific focus on the influence of inflammatory and immune responses. Next, we describe how changes in regulation are linked with various cardiovascular diseases. Recent insights from clinical diseases provide evidence for direct molecular links between inflammation and thrombosis, including atherosclerosis, chronic thromboembolic pulmonary hypertension, and COVID-19. Finally, we will briefly describe clinical implications for antithrombotic treatment.

Dual pathway inhibition as compared to acetylsalicylic acid monotherapy in relation to endothelial function in peripheral artery disease, a phase IV clinical trial

Objective

Dual pathway inhibition (DPI) by combining acetylsalicylic acid (ASA) with low-dose rivaroxaban has been shown to reduce cardiovascular events in patients with peripheral arterial disease (PAD) when compared to ASA monotherapy. A potential explanation is that inhibition of factor Xa improves endothelial function through crosstalk between coagulation and inflammatory pathways, subsequently attenuating the occurrence of cardiovascular events. We hypothesize that the addition of rivaroxaban to ASA in PAD patients leads to improved endothelial function.

Design

An investigator-initiated, multicentre trial investigating the effect of DPI on endothelial function.

Methods

Patients, diagnosed with PAD, were enrolled in two cohorts: cohort A (Rutherford I-III) and cohort B (Rutherford IV-VI). Participants received ASA monotherapy for a 4-weeks run-in period, followed by 12 weeks of DPI. Macro- and microvascular endothelial dysfunction were studied by measuring carotid artery reactivity upon sympathetic stimulus and by measuring plasma endothelin-1 concentrations, respectively. All measurements were performed during the use of ASA (baseline) and after 12 weeks of DPI.

Results

159 PAD patients (111 cohort A, 48 cohort B) were enrolled. Twenty patients discontinued study drugs early. Carotid artery constriction upon sympathetic stimulation at baseline (ASA) and after 12 weeks of DPI was similar in the total group, 22.0 vs. 22.7% (p = 1.000), and in the subgroups (Cohort A 22.6 vs. 23.7%, p = 1.000; cohort B 20.5 vs. 20.5%, p = 1.000), respectively. The mean concentration of plasma endothelin-1 at baseline and after 12 weeks of DPI did not differ, 1.70 ± 0.5 vs. 1.66 ± 0.64 pmol/L (p = 0.440) in the total group, 1.69 ± 0.59 vs. 1.62 ± 0.55 pmol/L in cohort A (p = 0.202), and 1.73 ± 0.53 vs. 1.77 ± 0.82 pmol/L in cohort B (p = 0.682), respectively.

Conclusion

Macro- and microvascular endothelial dysfunction, as reflected by carotid artery reactivity and plasma endothelin-1 concentrations, are not influenced in PAD patients by addition of low-dose rivaroxaban to ASA monotherapy for 12 weeks.

Trial registration

https://clinicaltrials.gov/ct2/show/NCT04218656.

The Evolution of Antiplatelet Therapy After Percutaneous Coronary Interventions: A 40-Year Journey

Antiplatelet therapy has a critical role to play in the successful management of patients undergoing percutaneous coronary intervention (PCI). Over the past 40 years, a multitude of participants worldwide have been enrolled in trials evaluating the impact of antiplatelet agents on clinical outcomes. The use of aspirin in unstable angina in the Canadian Aspirin trial was key to establishing the benefit of aspirin in acute coronary syndrome. The Clopidogrel in Unstable Angina to Prevent Recurrent Events (CURE) trial demonstrated that the P2Y12 inhibitor clopidogrel, when added to aspirin, reduced major cardiovascular events. While the use of antiplatelet agents in coronary artery disease antedates the introduction of PCI and remains the cornerstone of secondary prevention of atherosclerotic cardiovascular disease, strategies aiming to optimise their best use are still constantly evolving. In this review, the major randomised trials shaping current clinical practice for the use of aspirin and P2Y12 inhibitors in patients undergoing PCI are summarised, with a focus on aspirin-free strategies and on the role of P2Y12 inhibitor treatment before PCI, two major topics of ongoing investigation that are critical to patient care but that are not addressed in current practice guidelines. Multiple questions remain regarding the use of antiplatelet agents after PCI, including the personalisation of dosing, intensity, pharmacologic formulation, and duration of antiplatelet therapy based on individual patient characteristics and the optimal treatment of patients at high bleeding risk.

Thrombo-Inflammation and Immunological Response in Ischemic Stroke: Focusing on Platelet-Tregs Interaction

Strokes are mainly caused by thromboembolic obstruction of a major cerebral artery. Major clinical manifestations include paralysis hemiplegia, aphasia, memory, and learning disorders. In the case of ischemic stroke (IS), hyperactive platelets contribute to advancing an acute thrombotic event progression. Therefore, the principal goal of treatment is to recanalize the occluded vessel and restore cerebral blood flow by thrombolysis or mechanical thrombectomy. However, antiplatelets or thrombolytic therapy may increase the risk of bleeding. Beyond the involvement in thrombosis, platelets also contribute to the inflammatory process induced by cerebral ischemia. Platelet-mediated thrombosis and inflammation in IS lie primarily in the interaction of platelet receptors with endothelial cells and immune cells, including T-cells, monocytes/macrophages, and neutrophils. Following revascularization, intervention with conventional antiplatelet medicines such as aspirin or clopidogrel does not substantially diminish infarct development, most likely due to the limited effects on the thrombo-inflammation process. Emerging evidence has shown that T cells, especially regulatory T cells (Tregs), maintain immune homeostasis and suppress immune responses, playing a critical immunomodulatory role in ischemia-reperfusion injury. Hence, considering the deleterious effects of inflammatory and immune responses, there is an urgent need for more targeted agents to limit the thrombotic-inflammatory activity of platelets and minimize the risk of a cerebral hemorrhage. This review highlights the involvement of platelets in neuroinflammation and the evolving role of Tregs and platelets in IS. In response to all issues, preclinical and clinical strategies should generate more viable therapeutics for preventing and managing IS with immunotherapy targeting platelets and Tregs.

Prevention of arterial and venous thrombotic events in symptomatic peripheral arterial disease patients after lower extremity revascularization in the VOYAGER PAD trial: Dual anticoagulant/antiplatelet regimen vs antiplatelet therapy alone

BACKGROUND

Vascular disease burden after lower extremity revascularization (LER) comprises more than the first event, more vascular beds than the local arteries, and more than one clinical event type.

OBJECTIVES

Assess total arterial and venous thrombotic burden after LER for symptomatic peripheral artery disease (PAD) and effect of low-dose anticoagulation added to low-dose antiplatelet therapy.

PATIENTS/METHODS

VOYAGER PAD randomized 6564 symptomatic PAD patients undergoing LER to rivaroxaban 2.5 mg twice-daily or placebo on aspirin background. Marginal proportional-hazards models used to generate treatment hazard ratios and associated 95% CIs for first and total events; non-thrombotic deaths treated as competing terminal events. Incidence rates calculated as number of events per 100 patient-years follow-up.

RESULTS

Over 2.5 years (median), first and total thrombotic event rates: 7.1 and 10.3 events/100 patient-years, respectively, in placebo group. Two-thirds (925/1372) of total thrombotic events (arterial 95%, venous 5%) were nonfatal first events. Nearly one-third of patients with first event had a second arterial or venous thrombotic event. Rivaroxaban plus aspirin reduced first and total arterial and venous thrombotic events to 5.4 and 7.9 events/100 patient-years, respectively, a reduction in total thrombotic events over aspirin of 23% (HR: 0.77, 95%CI: 0.67-0.89, p = .0005), preventing 6.1 total arterial and venous thrombotic events at 3 years.

CONCLUSIONS

Assessing total arterial and venous thrombotic events, not just first events, provides more complete information about disease burden and absolute on-treatment impact. Following LER, judicious modulation of more than one coagulation pathway can provide broader benefit than intensifying inhibition of one hemostatic system component.

Sedentary behaviour and physical activity are associated with biomarkers of endothelial dysfunction and low-grade inflammation-relevance for (pre)diabetes: The Maastricht Study

AIMS/HYPOTHESIS

Biomarkers of endothelial dysfunction and low-grade inflammation are important in the pathogenesis of CVD and can potentially be modified by physical activity and sedentary behaviour. Effects of physical activity on biomarkers of endothelial dysfunction may be especially prominent in type 2 diabetes.

METHODS

In the population-based Maastricht Study (n = 2363, 51.5% male, 28.3% type 2 diabetes, 15.1% prediabetes [defined as impaired glucose tolerance and impaired fasting glucose]), we determined biomarkers of endothelial dysfunction and low-grade inflammation, and combined z scores were calculated. Physical activity and sedentary behaviour were measured by activPAL. Linear regression analyses were used with adjustment for demographic, lifestyle and cardiovascular risk factors.

RESULTS

The association between total, light, moderate-to-vigorous and vigorous intensity physical activity and sedentary time on the one hand and biomarkers of endothelial dysfunction on the other were generally significant and were consistently stronger in prediabetes and type 2 diabetes as compared with normal glucose metabolism status (p for interaction <0.05). Associations between physical activity and sedentary behaviour on the one hand and low-grade inflammation on the other were also significant and were similar in individuals with and without (pre)diabetes (p for interaction >0.05).

CONCLUSIONS/INTERPRETATION

Physical activity and sedentary behaviour are associated with biomarkers of endothelial dysfunction and low-grade inflammation. For biomarkers of endothelial dysfunction, associations between physical activity and sedentary behaviour were consistently stronger in (pre)diabetes than in normal glucose metabolism. Whether increasing physical activity or decreasing sedentary time can positively influence biomarkers of endothelial dysfunction in individuals with prediabetes and type 2 diabetes requires further study.