An exploratory look at NETosis in atherosclerosis

The immunologic phenotype of thrombi is associated with future vascular events after cerebral infarction

BACKGROUND

Thrombi retrieved from patients with acute ischemic stroke may contain prognostic information.

OBJECTIVE

To investigate the relationship between the immunologic phenotype of thrombi and future vascular events in patients with a stroke.

METHODS

This study included patients with acute ischemic stroke who underwent endovascular thrombectomy at Chung-Ang University Hospital in Seoul, Korea, between February 2017 and January 2020. Laboratory and histological variables were compared between patients with and without recurrent vascular events (RVEs). Kaplan-Meier analysis followed by the Cox proportional hazards model was used to identify factors related to RVE. Receiver operating characteristic (ROC) analysis was conducted to evaluate the performance of the immunologic score by combining immunohistochemical phenotypes to predict RVE.

RESULTS

A total of 46 patients were included in the study with 13 RVEs (mean±SD age, 72.8±11.3 years; 26 (56.5%) men). Thrombi with a lower percentage of programmed death ligand-1 expression (HR=11.64; 95% CI 1.60 to 84.82) and a higher number of citrullinated histone H3 positive cells (HR=4.19; 95% CI 0.81 to 21.75) were associated with RVE. The presence of high-mobility group box 1 positive cell was associated with reduced risk of RVE, but the association was lost after adjustment for stroke severity. The immunologic score, which consists of the three immunohistochemical phenotypes, showed good performance in predicting RVE (area under the ROC curve, 0.858; 95% CI 0.758 to 0.958).

CONCLUSIONS

The immunological phenotype of thrombi could provide prognostic information after stroke.

The role of platelet P2Y12 receptors in inflammation

Inflammation is a complex pathophysiological process underlying many clinical conditions. Platelets contribute to the thrombo-inflammatory response. Platelet P2Y12 receptors amplify platelet activation, potentiating platelet aggregation, degranulation and shape change. The contents of platelet alpha granules, in particular, act directly on leucocytes, including mediating platelet-leucocyte aggregation and activation via platelet P-selectin. Much evidence for the role of platelet P2Y12 receptors in inflammation comes from studies using antagonists of these receptors, such as the thienopyridines clopidogrel and prasugrel, and the cyclopentyltriazolopyrimidine ticagrelor, in animal and human experimental models. These suggest that antagonism of P2Y12 receptors decreases markers of inflammation with some evidence that this reduces incidence of adverse clinical sequelae during inflammatory conditions. Interpretation is complicated by pleiotropic effects such as those of the thienopyridines on circulating leucocyte numbers and of ticagrelor on adenosine reuptake. The available evidence suggests that P2Y12 receptors are prominent mediators of inflammation and P2Y12 receptor antagonism as a potentially powerful strategy in a broad range of inflammatory conditions. LINKED ARTICLES: This article is part of a themed issue on Platelet purinergic receptor and non-thrombotic disease. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v181.4/issuetoc.

Top Five Stories of the Cellular Landscape and Therapies of Atherosclerosis: Current Knowledge and Future Perspectives

Atherosclerosis (AS) is characterized by impairment and apoptosis of endothelial cells, continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells, which is documented as the traditional cellular paradigm. However, the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis, transdifferentiation and novel cell death forms such as ferroptosis, pyroptosis, and extracellular trap were reported. Discovery of novel pathological cellular landscapes provides a large number of therapeutic targets. On the other side, the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS burden. Stem cell- or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse effects. Given the complexity of pathological changes of AS, attempts to develop an almighty medicine based on single mechanisms could be theoretically challenging. In this review, the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical translation. The future challenges and improvements were also discussed.

Exploring the potential mechanism and molecular targets of Taohong Siwu Decoction against deep vein thrombosis based on network pharmacology and analysis docking

This study aims to investigate the mechanism of Taohong Siwu Decoction (THSWD) against deep vein thrombosis (DVT) using network pharmacology and molecular docking technology. We used the Traditional Chinese Medicine Systems Pharmacology database and reviewed literature to identify the main chemical components of THSWD. To find targets for DVT, we consulted GeneCards, Therapeutic Target Database, and PharmGKB databases. We used Cytoscape 3.8.2 software to construct herb-disease-gene-target networks. Additionally, we integrated drug targets and disease targets on the STRING platform to create a protein-protein interaction network. Then, we conducted Kyoto Encyclopedia of Genes and Genomes and gene ontology analysis. Finally, We employed the molecular docking method to validate our findings. We identified 56 potential targets associated with DVT and found 61 effective components. beta-sitosterol, quercetin, and kaempferol were the most prominent among these components. Our analysis of the protein-protein interaction network revealed that IL6, L1B, and AKT1 had the highest degree of association. Gene ontology analysis showed that THSWD treatment for DVT may involve response to inorganic substances, negative regulation of cell differentiation, plasma membrane protein complex, positive regulation of phosphorylation, and signaling receptor regulator activity. Kyoto Encyclopedia of Genes and Genomes analysis indicated that lipid and atherosclerosis, pathways in cancer, as well as the PI3K-Akt pathway are the main signal pathways involved. Molecular docking results demonstrated strong binding affinity between beta-sitosterol, quercetin, kaempferol, and AKT1 proteins as well as IL1B and IL6 proteins. The main targets for THSWD treatment of DVT may include AKT1, IL1B, and IL6. Beta-sitosterol, quercetin, and kaempferol may be the active ingredients responsible for producing this effect. These compounds may slow down the progression of DVT by regulating the inflammatory response through the PI3K/Akt pathway.

Update of Potential Biomarkers in Risk Prediction and Monitoring of Atherosclerosis in Systemic Lupus Erythematosus to Prevent Cardiovascular Disease

Systemic lupus erythematosus is a chronic connective tissue disease associated with an increased risk of premature atherosclerosis. It is estimated that approximately 10% of SLE patients develop significant atherosclerosis each year, which is responsible for premature cardiovascular disease that is largely asymptomatic. This review summarizes the most recent reports from the past few years on biomarkers of atherosclerosis in SLE, mainly focusing on immune markers. Persistent chronic inflammation of the vascular wall is an important cause of cardiovascular disease (CVD) events related to endothelial dysfunction, cell proliferation, impaired production and function of nitric oxide and microangiopathic changes. Studies on pathogenic immune mediators involved in atherosclerosis will be crucial research avenues for preventing CVD.

NETosis: an emerging therapeutic target in renal diseases

Introduction

Neutrophil extracellular traps (NETs) are web-like structures composed of nuclear and granular components. The primary role of NETS is to prevent the dissemination of microbes and facilitate their elimination. However, this process is accompanied by collateral proinflammatory adverse effects when the NET release becomes uncontrollable, or clearance is impaired. Although NET-induced organ damage is conducted primarily and indirectly via immune complexes and the subsequent release of cytokines, their direct effects on cells are also remarkable. NETosis plays a critical pathogenic role in several renal disorders, such as the early phase of acute tubular necrosis, anti-neutrophil cytoplasmic antibody-mediated renal vasculitis, lupus nephritis, thrombotic microangiopathies, anti-glomerular basement membrane disease, and diabetic nephropathy. Their substantial contribution in the course of these disorders makes them a desirable target in the therapeutic armamentarium. This article gives an in-depth review of the heterogeneous pathogenesis and physiological regulations of NETosis and its pivotal role in renal diseases. Based on the pathogenesis, the article also outlines the current therapeutic options and possible molecular targets in the treatment of NET-related renal disorders.

Methods

We carried out thorough literature research published in PubMed and Google Scholar, including a comprehensive review and analysis of the classification, pathomechanisms, and a broad spectrum of NET-related kidney disorders.

Conclusions

NETosis plays a pivotal role in certain renal diseases. It initiates and maintains inflammatory and autoimmune disorders, thus making it a desirable target for improving patient and renal outcomes. Better understanding and clinical translation of the pathogenesis are crucial aspects to treatment, for improving patient, and renal outcomes.

Screening of Potential Circulating Diagnostic Biomarkers and Molecular Mechanisms of Systemic Lupus Erythematosus-Related Myocardial Infarction by Integrative Analysis

Background

The risk of acute myocardial infarction (AMI) is elevated in patients with systemic lupus erythematosus (SLE), and it is of great clinical value to identify potential molecular mechanisms and diagnostic markers of AMI associated with SLE by analyzing public database data and transcriptome sequencing data.

Methods

AMI and SLE-related sequencing datasets GSE62646, GSE60993, GSE50772 and GSE81622 were downloaded from the Gene Expression Omnibus (GEO) database and divided into prediction and validation cohorts. To identify the key genes associated with AMI related to SLE, WGCNA and DEGs analysis were performed for the prediction and validation cohorts, respectively. The related signaling pathways were identified by GO/KEGG enrichment analysis. Peripheral blood mononuclear cells (PBMCs) from patients with AMI were collected for transcriptome sequencing to validate the expression of key genes in patients with AMI. Least absolute shrinkage and selection operator (LASSO) regression analysis was applied to screen diagnostic biomarkers. The diagnostic efficacy of biomarkers was validated by ROC analysis, and the CIBERSORTx platform was used to analyze the composition of immune cells in AMI and SLE.

Results

A total of 108 genes closely related to AMI and SLE were identified in the prediction cohort, and GO/KEGG analysis showed significantly enriched signaling pathways. The results of differential analysis in validation cohort were consistent with them. By transcriptional sequencing of PBMCs from peripheral blood of AMI patients, combined with the results of prediction and validation cohort analysis, seven genes were finally screened out. LASSO analysis finally identifies DYSF, LRG1 and CSF3R as diagnostic biomarkers of SLE-related-AMI. CIBERSORTx analysis revealed that the biomarkers were highly correlated with neutrophils.

Conclusion

Neutrophil degranulation and NETs formation play important roles in SLE-related AMI, and DYSF, LRG1 and CSF3R were identified as important diagnostic markers for the development and progression of SLE-related AMI.

Network pharmacology prediction and molecular docking-based strategy to discover the potential pharmacological mechanism of Huang-Qi-Gui-Zhi-Wu-Wu decoction against deep vein thrombosis

BACKGROUND

Huangqi Guizhi Wuwu decoction (HQGZWWD) has been used to treat and prevent deep vein thrombosis (DVT) in China. However, its potential mechanisms of action remain unclear. This study aimed to utilize network pharmacology and molecular docking technology to elucidate the molecular mechanisms of action of HQGZWWD in DVT.

METHODS

We identified the main chemical components of HQGZWWD by reviewing the literature and using a Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. We used GeneCards and Online Mendelian Inheritance in Man databases to identify the targets of DVT. Herb-disease-gene-target networks using Cytascape 3.8.2 software; a protein-protein interaction (PPI) network was constructed by combining drug and disease targets on the STRING platform. Additionally, we conducted Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. Finally, molecular docking verification of active components and core protein targets was conducted.

RESULTS

A total of 64 potential targets related to DVT were identified in HQGZWWD, with 41 active components; quercetin, kaempferol, and beta-sitosterol were the most effective compounds. The PPI network analysis revealed that AKT1, IL1B, and IL6 were the most abundant proteins with the highest degree. GO analysis indicated that DVT treatment with HQGZWWD could involve the response to inorganic substances, positive regulation of phosphorylation, plasma membrane protein complexes, and signaling receptor regulator activity. KEGG analysis revealed that the signaling pathways included pathways in cancer, lipid and atherosclerosis, fluid shear stress and atherosclerosis, and the phosphatidylinositol 3-kinases/protein kinase B(PI3K-Akt) and mitogen-activated protein kinase (MAPK) signaling pathways. The molecular docking results indicated that quercetin, kaempferol, and beta-sitosterol exhibited strong binding affinities for AKT1, IL1B, and IL6.

CONCLUSION

Our study suggests that AKT1, IL1B, and IL6 are promising targets for treating DVT with HQGZWWD. The active components of HQGZWWD likely responsible for its effectiveness against DVT are quercetin, kaempferol, and beta-sitosterol, they may inhibit platelet activation and endothelial cell apoptosis by regulating the PI3K/Akt and MAPK signaling pathways, slowing the progression of DVT.

Exosomal non-coding RNAs: Emerging therapeutic targets in atherosclerosis

Atherosclerosis is an LDL-driven and inflammatory disorder of the sub-endothelial space. Available data have proposed that various factors could affect atherosclerosis pathogenesis, including inflammation, oxidation of LDL particles, endothelial dysfunction, foam cell formation, proliferation, and migration of vascular smooth muscle cells (VSMCs). In addition, other research indicated that the crosstalk among atherosclerosis-induced cells is a crucial factor in modulating atherosclerosis. Extracellular vesicles arenanoparticleswith sizes ranging from 30-150 nm, playing an important role in various pathophysiological situations. Exosomes, asa form of extracellular vesicles, could affect the crosstalk between sub-endothelial cells. They can transport bioactive components like proteins, lipids, RNA, and DNA. As an important cargo in exosomes, noncoding RNAs (ncRNAs) including microRNAs, long noncoding RNAs, and circular RNAs could modulate cellular functions by regulating the transcription, epigenetic alteration, and translation. The current work aimed to investigate the underlying molecular mechanisms of exosomal ncRNA as well as their potential as a diagnostic biomarker and therapeutic target in atherosclerosis.

Discovery of a novel, highly potent and orally bioavailable pyrrolidinone indole series of irreversible Myeloperoxidase (MPO) inhibitors

Myeloperoxidase (MPO) is a heme-containing peroxidase from phagocytic cells, which plays an important role in the innate immune response. The primary anti-microbial function of MPO is achieved by catalyzing the oxidation of halides by hydrogen peroxide (H₂O₂). Upon activation of phagocytes, MPO activity is detectable in both phagosomes and extracellularly, where it can remain or transcytose into interstitial compartments. Activated MPO leads to oxidative stress and tissue damage in many inflammatory states, including cardiovascular disease. Starting from a low molecular weight (LMW) high throughput screening (HTS) hit, here we report the discovery of a novel pyrrolidinone indole (IN-4) as a highly potent MPO inhibitor. This compound displays similar in vitro potency across peroxidation, plasma and NETosis assays. In a dilution/dialysis study, <5% of the original MPO activity was detected post-incubation of MPO with IN-4, suggesting irreversible enzyme inhibition. A fast MPO inactivation rate (k_inact/K_i) and low partition ratio (k₃/k₄) make IN-4 kinetic properties attractive for an MPO inhibitor. This compound also displays significant selectivity over the closely related thyroid peroxidase (TPO), and is selective for extracellular MPO over intracellular (neutrophil) MPO. Moreover, IN-4 shows good exposure, low clearance and high oral bioavailability in mice, rats and dogs. The high in vitro MPO activity and high oral exposure observed with IN-4 result in a dose-dependent inhibition of MPO activity in three mouse models of inflammation. In conclusion, IN-4 is a novel, potent, mechanism-based and selective MPO inhibitor, which may be used as superior therapeutic agent to treat multiple inflammatory conditions, including cardiovascular disease.

Cardiovascular outcomes in patients with cancer during a 5-year follow-up: Results from a French administrative database

BACKGROUND

Limited data are available regarding the optimal management and prognosis of patients with cancer who develop an acute myocardial infarction.

AIM

The objective of this study was to analyse the characteristics and outcomes of patients according to cancer and myocardial infarction occurrence.

METHODS

Based on the French administrative hospital discharge database, the study collected information for all consecutive patients seen in French hospitals in 2013, excluding those with a history of myocardial infarction. The population was divided into two groups according to their history of cancer. We studied the following outcomes: all-cause and cardiovascular mortality; acute myocardial infarction; and ischaemic stroke. Data were collected after a 5-year follow-up.

RESULTS

Between 2013 and 2019, 3,381,472 patients were seen in French hospitals; among them, 3,323,757 had no history of myocardial infarction. Patients with a history of cancer (n=497,593) had higher incidences of all-cause mortality (17.82%/year vs 3.79%/year), cardiovascular mortality (1.61%/year vs 1.17%/year), myocardial infarction (0.82%/year vs 0.61%/year) and ischaemic stroke (0.91%/year vs 0.62%/year) compared with patients without cancer (n=2,826,164). After performing an adjusted competing-risk analysis, the cumulative incidence of acute myocardial infarction, cardiovascular death and ischaemic stroke incidence was found to be lower in patients with a history of cancer, whereas death of non-cardiac origin was more prevalent in patients with a history of cancer.

CONCLUSIONS

In this observational study, we have shown that patients with cancer have a higher incidence of all-cause mortality, cardiovascular mortality and myocardial infarction. However, multivariable analysis showed a lower cumulative incidence of these events.

Non-Traditional Pro-Inflammatory and Pro-Atherosclerotic Risk Factors Related to Systemic Lupus Erythematosus

Cardiovascular diseases (CVD) are one of the leading causes of high mortality in patients with systemic lupus erythematosus (SLE). The Framingham risk score and other traditional risk factors do not fully reflect the CVD risk in SLE patients. Therefore, in order to stratify these high-risk patients, additional biomarkers for subclinical CVD are needed. The mechanisms of atherogenesis in SLE are still being investigated. During the past decades, many reports recognized that inflammation plays a crucial role in the development of atherosclerosis. The aim of this report is to present novel proinflammatory and pro-atherosclerotic risk factors that are closely related to SLE inflammation and which determine an increased risk for the occurrence of early cardiovascular events.

Thromboembolic Disease and Cardiac Thrombotic Complication in COVID-19: A Systematic Review

The coronavirus 2019 pandemic has affected many healthcare systems worldwide. While acute respiratory distress syndrome (ARDS) has been well-documented in COVID-19, there are several cardiovascular complications, such as myocardial infarction, ischaemic stroke, and pulmonary embolism, leading to disability and death. The link between COVID-19 and increasing thrombogenicity potentially occurs due to numerous different metabolic mechanisms, ranging from endothelial damage for direct virus infection, associated excessive formation of neutrophil extracellular traps (NETs), pathogenic activation of the renin-angiotensin-aldosterone system (RAAS), direct myocardial injury, and ischemia induced by respiratory failure, all of which have measurable biomarkers. A search was performed by interrogating three databases (MEDLINE; MEDLINE In-Process and Other Non-Indexed Citations, and EMBASE). Evidence from randomized controlled trials (RCT), prospective series, meta-analyses, and unmatched observational studies were evaluated for the processing of the algorithm and treatment of thromboembolic disease and cardiac thrombotic complications related to COVID-19 during SARS-CoV-2 infection. Studies out with the SARS-Cov-2 infection period and case reports were excluded. A total of 58 studies were included in this analysis. The role of the acute inflammatory response in the propagation of the systemic inflammatory sequelae of the disease plays a major part in determining thromboembolic disease and cardiac thrombotic complication in COVID-19. Some of the mechanisms of activation of these pathways, alongside the involved biomarkers noted in previous studies, are highlighted. Inflammatory response led to thromboembolic disease and cardiac thrombotic complications in COVID-19. NETs play a pivotal role in the pathogenesis of the inflammatory response. Despite moving into the endemic phase of the disease in most countries, thromboembolic complications in COVID-19 remain an entity that substantially impacts the health care system, with long-term effects that remain uncertain. Continuous monitoring and research are required.

Association of S100A8/A9 with lipid-rich necrotic core and treatment with biologic therapy in patients with psoriasis: results from an observational cohort study

Psoriasis is a systemic inflammatory disease with increased risk of atherosclerotic events and premature cardiovascular disease. S100A7, A8/A9, and A12 are protein complexes that are produced by activated neutrophils, monocytes, and keratinocytes in psoriasis. Lipid-rich necrotic core (LRNC) is a high-risk coronary plaque feature previously found to be associated with cardiovascular risk factors and psoriasis severity. LRNC can decrease with biologic therapy, but how this occurs remains unknown. We investigated the relationship between S100 proteins, LRNC, and biologic therapy in psoriasis. S100A8/A9 associated with LRNC in fully adjusted models (β = 0.27, P = 0.009, n=125 psoriasis patients with available coronary CT angiography scans, LRNC analyses, and serum S100A7, S100A8, S100A9, S100A12, and S100A8/A9 levels). At one year, in patients receiving biologic therapy (36 of 73 patients had 1-year CCTA scans available), a 79% reduction in S100A8/A9 levels (-172 (-291.7-26.4) vs -29.9 (-137.9- 50.5) P = 0.04) and a 0.6 mm² reduction in average LRNC area (0.04 (-0.48-0.77) vs -0.56 (-1.8- 0.13); P = 0.02) were noted. These results highlight the potential role of S100A8/A9 in the development of high-risk coronary plaque in psoriasis.

Insights into the Role of Neutrophils and Neutrophil Extracellular Traps in Causing Cardiovascular Complications in Patients with COVID-19: A Systematic Review

Background: The coronavirus disease 2019 (COVID-19) pandemic caused by the SARS-CoV-2 virus has resulted in significant mortality and burdening of healthcare resources. While initially noted as a pulmonary pathology, subsequent studies later identified cardiovascular involvement with high mortalities reported in specific cohorts of patients. While cardiovascular comorbidities were identified early on, the exact manifestation and etiopathology of the infection remained elusive. This systematic review aims to investigate the role of inflammatory pathways, highlighting several culprits including neutrophil extracellular traps (NETs) which have since been extensively investigated. Method: A search was conducted using three databases (MEDLINE; MEDLINE In-Process & Other Non-Indexed Citations and EMBASE). Data from randomized controlled trials (RCT), prospective series, meta-analyses, and unmatched observational studies were considered for the processing of the algorithm and treatment of inflammatory response during SARS-CoV-2 infection. Studies without the SARS-CoV-2 Infection period and case reports were excluded. Results: A total of 47 studies were included in this study. The role of the acute inflammatory response in the propagation of the systemic inflammatory sequelae of the disease plays a major part in determining outcomes. Some of the mechanisms of activation of these pathways have been highlighted in previous studies and are highlighted. Conclusion: NETs play a pivotal role in the pathogenesis of the inflammatory response. Despite moving into the endemic phase of the disease in most countries, COVID-19 remains an entity that has not been fully understood with long-term effects remaining uncertain and requiring ongoing monitoring and research.

Inhibition of NETosis for treatment purposes: friend or foe?

Active neutrophils participate in innate and adaptive immune responses through various mechanisms, one of the most important of which is the formation and release of neutrophil extracellular traps (NETs). The NETs are composed of network-like structures made of histone proteins, DNA and other released antibacterial proteins by activated neutrophils, and evidence suggests that in addition to the innate defense against infections, NETosis plays an important role in the pathogenesis of several other non-infectious pathological states, such as autoimmune diseases and even cancer. Therefore, targeting NET has become one of the important therapeutic approaches and has been considered by researchers. NET inhibitors or other molecules involved in the NET formation, such as the protein arginine deiminase 4 (PAD4) enzyme, an arginine-to-citrulline converter, participate in chromatin condensation and NET formation, is the basis of this therapeutic approach. The important point is whether complete inhibition of NETosis can be helpful because by inhibiting this mechanism, the activity of neutrophils is suppressed. In this review, the biology of NETosis and its role in the pathogenesis of some important diseases have been summarized, and the consequences of treatment based on inhibition of NET formation have been discussed.

NETosis in ischemic/reperfusion injuries: An organ-based review

Neutrophil extracellular trap (NETosis), the web-like structures induced by neutrophil death, is an important inflammatory mechanism of the immune system leading to reactive oxygen species production/coagulopathy, endothelial dysfunction, atherosclerosis, and ischemia. NETosis exerts its role through different mechanisms such as triggering Toll-like receptors, inflammatory cytokines, platelet aggregation, neutrophil activation/infiltration, and vascular impairment. NETosis plays a key role in the prognosis of coronary artery disease, ischemic injury of kidney, lung, gastrointestinal tract and skeletal muscles. In this review, we explored the molecular mechanisms involved in NETosis, and ischemic/reperfusion injuries in body organs.

Angiopoietin 1 release from human neutrophils is independent from neutrophil extracellular traps (NETs)

Background

Neutrophils induce the synthesis and release of angiopoietin 1 (Ang1), a cytosolic growth factor involved in angiogenesis and capable of inducing several pro-inflammatory activities in neutrophils. Neutrophils also synthesize and release neutrophil extracellular traps (NETs), comprised from decondensed nuclear DNA filaments carrying proteins such as neutrophil elastase (NE), myeloperoxidase (MPO), proteinase 3 (PR3) and calprotectin (S100A8/S100A9), which together, contribute to the innate immune response against pathogens (e.g., bacteria). NETs are involved in various pathological conditions through pro-inflammatory, pro-thrombotic and endothelial dysfunction effects and have recently been found in heart failure (HF) and type 2 diabetes (T2DM) patients. The aim of the present study was to investigate the role of NETs on the synthesis and release of Ang1 by the neutrophils in patients with T2DM and HF with preserved ejection fraction (HFpEF) (stable or acute decompensated; ADHFpEF) with or without T2DM.

Results

Our data show that at basal level (PBS) and upon treatment with LPS, levels of NETs are slightly increased in patients suffering from T2DM, HFpEF ± T2DM and ADHF without (w/o) T2DM, whereas this increase was significant in ADHFpEF + T2DM patients compared to healthy control (HC) volunteers and ADHFpEF w/o T2DM. We also observed that treatments with PMA or A23187 increase the synthesis of Ang1 (from 150 to 250%) in HC and this effect is amplified in T2DM and in all cohorts of HF patients. Ang1 is completely released (100%) by neutrophils of all groups and does not bind to NETs as opposed to calprotectin.

Conclusions

Our study suggests that severely ill patients with HFpEF and diabetes synthesize and release a greater abundance of NETs while Ang1 exocytosis is independent of NETs synthesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12865-021-00442-8.

Basophil Blood Cell Count Is Associated With Enhanced Factor II Plasma Coagulant Activity and Increased Risk of Mortality in Patients With Stable Coronary Artery Disease: Not Only Neutrophils as Prognostic Marker in Ischemic Heart Disease

Background White blood cell count, which is inexpensive and widely available in clinical practice, has been proposed to provide prognostic information in coronary artery disease (CAD). Elevated levels of white blood cell subtypes may play different roles in atherothrombosis and predict cardiovascular outcomes. Methods and Results The association between white blood cell counts and mortality was evaluated in 823 subjects with angiographically demonstrated and clinically stable CAD in an observational-longitudinal study. The correlation among white blood cell counts and factor II plasma coagulant activity was analyzed in 750 subjects (554 CAD and 196 CAD-free) not taking anticoagulant drugs. Subjects with overt leukocytosis or leukopenia were excluded. In the longitudinal study after a median follow-up of 61 months, 160 (19.4%) subjects died, 107 (13.0%) of whom from cardiovascular causes. High levels of neutrophils, monocytes, eosinophils, and basophils were associated with an increased mortality rate. In multiadjusted Cox regression models, only neutrophils and basophils remained predictors of total and cardiovascular mortality. The associations remained significant after adjustment for traditional cardiovascular risk factors and by including D-dimer and the chemokine CXCL12 in the regression models. Neutrophils and basophils were also significant predictors of factor II plasma coagulant activity variability after adjustment for blood cell counts, age, sex, inflammatory markers, CAD diagnosis, and prothrombin G20210A polymorphism. Factor II plasma coagulant activity was similarly increased in subjects with high neutrophil and basophil counts and in carriers of the prothrombin 20210A allele. Conclusions Both high neutrophil and basophil blood counts may predict mortality in patients with clinically stable CAD and are associated with enhanced factor II plasma coagulant activity, thereby suggesting underlying prothrombotic mechanisms.

Synergistic Effects of Cryptotanshinone and Senkyunolide I in Guanxinning Tablet Against Endogenous Thrombus Formation in Zebrafish

Thrombosis is a key pathological event in cardiovascular diseases, and is also the most important targeting process for their clinical management. New drug development in thrombosis treatment is still in great demand. According to the traditional Chinese medicine (TCM) theory, thrombosis belongs to the syndrome of blood stasis. Salvia miltiorrhiza Bunge and Ligusticum striatum DC. are two common TCM herbs with long-term documented function in promoting blood circulation and inhibiting thrombosis, especially when used together. Guanxinning Tablet, a modern Chinese drug which contains extracts of the two herbs, also showed strong therapeutic effects in coronary heart disease. However, the pharmacological mechanism is still lacking for the compatibility of the two herbs. Here, through zebrafish-based in vivo fluorescence screening, we demonstrated the synergistic effects between S. miltiorrhiza Bunge and L. striatum DC. in regulating endogenous thrombosis. Moreover, combined with high-resolution mass spectrometry, the main compounds of the botanical drugs were analyzed and screened in our model system. Interestingly, cryptotanshinone and senkyunolide I, two representative compounds, respectively derived from the two herbs, also showed synergistic antithrombotic effects. Further analysis suggested that they may regulate thrombi formation at different levels via multiple signaling pathways, including oxidative stress, platelet activation and coagulation cascade. Taken together, our findings provided solid biological supports toward the drug compatibility theory of TCM, and suggested cryptotanshinone and senkyunolide I as promising drug candidates in thrombosis management.

Cardiovascular Consequences of Autoimmune Rheumatic Diseases

The increased risk of cardiovascular disease (CVD) among patients with autoimmune rheumatic diseases such as rheumatoid arthritis, spondyloarthritis and systemic lupus erythematosus has been extensively documented. Sub-clinical atherosclerosis can be assessed using various non-invasive imaging techniques. However, the mechanisms underlying the higher risk of atherosclerotic CVD in patients with autoimmune rheumatic diseases are not fully known, although they seem to include chronic low-grade systemic inflammation leading to prolonged endothelial activation, accompanied by a pro-thrombotic/pro-coagulant and autoantibody state. Furthermore, sub-clinical atherosclerosis is also influenced by other traditional risk factors for CVD. Including the individual components of the metabolic syndrome (MetS: obesity, impaired glucose metabolism, dyslipidemia and high blood pressure), the degree of which is higher in these patients than in controls. The aim of this narrative review is to discuss the CV manifestations and risk factors involved in the increased risk of CVD among patients with autoimmune rheumatic diseases.

Stem cell-derived exosomes: Role in the pathogenesis and treatment of atherosclerosis

Atherosclerosis (AS) is a chronic inflammatory vascular disease characterized by the accumulation of lipids and inflammatory debris in large arteries, high morbidity, and AS-related disease mortality. AS is a complex process, involving endothelial cell dysfunction and inflammation, smooth muscle cell proliferation, and macrophage activation. However, the currently available therapies for AS are not ideal, thus requiring development of novel treatment strategies. Exosomes are bi-lipid membranous extracellular containing multifarious cargo, such as proteins, lipids, micro ribonucleic acid (miRNAs), messenger RNAs, and long non-coding RNAs. Moreover, exosomes reportedly participate in various AS processes. Specifically, stem cell-derived exosomes can regulate the occurrence and development of AS, exhibiting the ability to overcome the limitations associated with AS treatment and stem cell therapy. In this paper, we review the pathological mechanism of AS and discuss the role of exosomes and stem cell-derived exosomes in AS progression. We conclude by suggesting new therapeutic strategies for treating AS with stem cell-derived exosomes in the hope of improving the clinical treatment of AS.

CXCL-8-dependent and -independent neutrophil activation in COPD: experiences from a pilot study of the CXCR2 antagonist danirixin

The implications of these findings are significant for development of CXCR2 antagonists and other mechanisms targeting neutrophil activation or NETosis, suggesting that IL-8-dependent mechanisms will only work in a subset of COPD patients https://bit.ly/32SeisO.

Natural nodular worm infection in goats induces eosinophil extracellular DNA trap (EET) formation

Extracellular DNA Trap (ET) formation by granulocyte is a strong innate immune machinery that plays crucial roles in trapping and killing of pathogens. Here, we show Eosinophil Extracellular DNA Trap (EET) formation in goats naturally infected with nodular worms (Oesophagostomum columbianum, Strongyloidae: Nematoda). By a slaughterhouse based survey, we found that 60% goats were infected with nodular worms. We detected numerous, hard and pale yellow to dark black nodules of variable sizes (0.25-2 cm) in the large intestine and the number of nodules were significantly (p < .05) higher in the cecum (21.7 ± 17.9) than in the colon (10.1 ± 9.9). Histologically, pink colored circumscribed caseous mass was surrounded by a dense zone of infiltration and fibrous proliferation along with massive infiltration of eosinophils in and around the necrotic mass. DAPI staining revealed huge accumulation of extracellular DNA, which formed wide ridge like structure surrounding the necrotic zone. Massive release of eosinophils cationic proteins (ECP), a helmintho-toxic substance, was found into the lesions. Collectively, our results suggest that nodular worm infection induces EETosis and ECP release, and is one of the major parasitic problem affecting Black Bengal goats that causes distortion of normal architecture of the gut wall.

Neutrophil Extracellular Traps Generation Relates with Early Stage and Vascular Complications in Systemic Sclerosis

Systemic sclerosis (SSc) is a systemic disease characterized by a great clinical and immunological heterogeneity whose pathophysiology is still being unraveled. Recently, innate immunity has been proposed to participate to the pathogenesis of SSc. In this study, we investigated the release of neutrophil extracellular traps (NETs) according to patient phenotype. Polymorphonuclear neutrophils (PMN) from 34 SSc patients and 26 healthy controls were stimulated by serum from SSc or healthy subject. NETs were visualized using epifluorescence microscope after DNA, myeloperoxidase, and Histone H3 tagging. Area of NETs were quantified using an original macro running in ImageJ^® software. PMN from SSc patients were significantly more prone to releasing NETs than control PMN after autologous stimulation. PMN from patients with severe vascular complications (pulmonary arterial hypertension, digital ulcers) produced more NETs than PMN from other SSc patients and their aberrant NET production appeared to be sustained over time. In patients with pulmonary interstitial disease or extensive cutaneous fibrosis, NET production was high at an early stage of the disease before progressively decreasing. Both serum factors and PMN activation status were involved in the enhanced production of NETs in SSc. Consequently, neutrophils and especially NETosis represent new physiopathological and therapeutic fields in SSc.

Helicobacter pylori as an Initiating Factor of Complications in Patients With Cirrhosis: A Single-Center Observational Study

Background and Aim: The relationship between liver cirrhosis and Helicobacter pylori (H. pylori) is a debatable matter. The aim of this study is to evaluate the possible association between H. pylori infection and liver cirrhosis. Methods: A single-center prospective cohort pilot study of 558 patients with cirrhosis was followed up for 1 year. Serum C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide (NO), vascular endothelial growth factor (VEGF) levels and Fecal H. pylori antigen were evaluated by enzyme-linked immunosorbent assay (ELISA). All patients with positive H. pylori were treated and then followed up for 3 months. Participants with eradicated H. pylori were followed up for one further year. Results: H. pylori-positive patients (48.4%) were associated with increased levels of serum CRP, TNF-α, IL-6, NO, and VEGF, as well as increased incidence of varices, portal hypertensive gastropathy, gastric antral vascular ectasia, hepatocellular carcinoma (HCC), spontaneous bacterial peritonitis, hepatic encephalopathy, portal vein thrombosis (PVT), and hepatorenal syndrome (all P < 0.05). Multivariate analysis models revealed that the presence of H. pylori was an independent risk variable for the development of portal vein thrombosis and hepatocellular carcinoma (P = 0.043, P = 0.037) respectively. After treatment of H. pylori infection, there was a significant reduction in all measured biochemical parameters and reported cirrhotic complications (all P < 0.05). Conclusion: Incidence of PVT and HCC development increased with H. pylori infection through increased inflammatory markers and vascular mediators. Moreover, its eradication may reduce the incidence of these complications.

Neutrophil extracellular traps: The core player in vascular complications of diabetes mellitus

Diabetes mellitus (DM) is the most important metabolic disease with major threat for public health and increased risk of premature death. The prevalence of DM steadily rises in developing and developed countries achieving the epidemic level. Manifestation and progression of DM corresponds to developing vasculopathies, such as retinopathy, micro- and macro angiopathies, which negatively influence on clinical outcomes and quality-of-life. Although there are remarkable differences in the prevalence of vasculopathy in various types of DM, hyperglycemia and lipotoxicity are discussed as a major factors contributing to vascular complications partly through inducing neutrophil extracellular trap (NET). The NET or NETosis is unique form of cell death, which is an important core component of innate immune system. The review is dedicated the role of NET as a link between endothelium, inflammation and thrombosis that is crucial for development of DM-induced vasculopathy. It has suggested that NET formation could be not just a target for the DM care, but also a biomarker for stratification of DM patients at higher risk of vascular complications.

Neutrophil-to-lymphocyte ratio and its relation with pro-inflammatory mediators, visceral adiposity and carotid intima-media thickness in population with obesity

BACKGROUND

Atherosclerosis represents a cardiovascular risk. Chronic inflammation is a key factor for atherogenic progression. Neutrophil-to-lymphocyte ratio (NLR) has been proposed as a novel biomarker for cardiovascular risks. We aimed to explore whether NLR was related to surrogate pro-atherogenic promoters driving atherogenic progression, as measured by carotid intima-media thickness (CIMT).

STUDY DESIGN

Thirty-one patients with obesity candidates for bariatric surgery were recruited from Centro Médico Nacional "20 de Noviembre", ISSSTE, Mexico City. The results are part of the "CROP" study (NCT03561987). NLR was calculated from routine complete blood count, and its relation with plasma pro-inflammatory mediators (hsCRP, TNF-α and IL-1β), adipokines (adiponectin and leptin), adiposity markers (visceral adipose tissue [VAT] determined from CT scan image and VAT individual adipocyte area at histological sample) and CIMT were determined.

RESULTS

Neutrophil-to-lymphocyte ratio correlated with hsCRP (Spearman's r = 0.70 [95% CI 0.46 to 0.85], P < 0.01), TNF-α (r = 0.69 [0.44 to 0.84], P < 0.0001) and adiponectin (r = -0.69 [-0.84 to -0.45], P < 0.03), as well as with VAT individual adipocyte area (r = 0.64 [0.37 to 0.81], P < 0.0001) and with VAT area (r = 0.43; [0.07 to 0.68], P < 0.01). Leptin and adiponectin showed further independent association with higher NLR (multivariate regression analysis OR 7.9 [95% CI 1.1 to 56.2] P = 0.03 and 0.1 [0.01 to 1.0] P = 0.05, respectively). Moreover, NLR distribution significantly varied between subgroups divided according to progressive CIMT (P = 0.05); whereas adiponectin and VAT adipocyte area associated with CIMT > 0.9 mm (univariate analysis OR 0.1 [0.01 to 1.0] P = 0.05 and 13.1 [1.4 to 126.3] P = 0.03, respectively).

CONCLUSION

Neutrophil-to-lymphocyte ratio was related to pro-inflammatory, adiposity biomarkers and progressive subclinical atherogenesis.

L-sepiapterin restores SLE serum-induced markers of endothelial function in endothelial cells

OBJECTIVE

SLE serves as an independent risk factor` for endothelial dysfunction (ED) not explained by Framingham risk factors. We sought to understand the development of SLE-induced ED on a cellular level in order to develop strategies aimed at reversing cellular abnormalities. This study assessed the impact of SLE patient serum on endothelial nitric oxide synthase (eNOS), nitric oxide (NO) production and functional changes in the cell.

METHODS

Human umbilical vein endothelial cells (HUVECs) cultured in serum of either SLE (n=25) or healthy patients (n=14) or endothelial basal medium 2 (EBM-2) culture media supplemented with fetal bovine serum with or without L-sepiapterin were used for our studies. We applied the fluorescent probe DAF-FM diacetate for intracellular NO detection using flow cytometry. Total RNA isolates were analysed using reverse transcription PCR for eNOS mRNA expression. Oxygen consumption rate was determined using seahorse analysis. Neutrophil adhesion and migration were determined using a calcein AM microscopy assay.

RESULTS

The mRNA expression of eNOS was increased in SLE cultured HUVECs compared with healthy control (p<0.05). The SLE eNOS mRNA level correlated with SLE patient age (p=0.008); however, this trend was not observed with healthy patients. SLE serum reduced NO production in HUVECs compared with EBM-2 cultured cells (p<0.05). Co-treatment of endothelial cells with L-sepiapterin preserved HUVEC capacity to produce NO in SLE conditions (p<0.01). SLE serum enhanced neutrophil migration (p<0.01) but not neutrophil adhesion compared with healthy controls. The bioenergetic health index was not different.

CONCLUSIONS

SLE likely causes disruption of endothelial cell eNOS function and NO modulated pathways.

The role of neutrophils in thrombosis

Despite significant evidence implicating an important role for neutrophils in thrombosis, their impact on the thrombotic process has remained a matter of controversy. Until 2010, platelets, coagulation factors, fibrinogen and monocytes were implicated in the thrombotic process. Several studies conducted over the last decade now support the growing notion that neutrophils indeed do contribute significantly to this process. Neutrophils can contribute to pathologic venous and arterial thrombosis or 'immunothrombosis' by the release of neutrophil extracellular traps (NETs) and NET release is emerging as a major contributor to thrombogenesis in pathologic situations such as sepsis and malignancy. Further, blood-cell derived microparticles, including those from neutrophils, have been implicated in thrombus formation. Finally, inflammasome activation in the neutrophil identifies another important mechanism that may be operative in neutrophil-driven risk for thrombosis. The knowledge of these roles of neutrophils in thrombosis may pave the road for novel anti-thrombotic agents in the future that do not affect hemostasis.

Nuclear factor kappa B in patients with a history of unstable angina: case re-opened

This study aims at assessing NF-kB activity in unstable angina (UA) patients free of symptoms after a 1 year follow-up (1YFU). Plasma oxidized low-density lipoproteins (oxLDL), circulating NF-kB, Interleukin 6 (IL-6) and Interleukin 1β (IL-1β), high-sensitivity C-reactive protein (hs-CRP), as markers of oxidative stress and inflammation and plasma double-stranded DNA (ds-DNA), as marker of Neutrophil Extracellular Traps (NETs), were measured in 23 of the previously enrolled 27 UA patients. These measurements were compared to the UA data at baseline, and then compared to the data derived from the stable angina (SA) and controls (C) enrolled in our previous study (we demonstrated that UA had higher levels of NF-kB compared to SA and C). After a 1YFU, UA patients show a significant decrease in NF-kB, IL-6, hs-CRP, oxLDL, and ds-DNA plasma levels (p < 0.001) and in IL-1β and White Blood Cells (WBC) (p < 0.005), without differences in lipid and glucose assessment. If compared to SA and C, UA after a 1YFU have higher levels of NF-kB, IL-6, ds-DNA, WBC, and oxLDL compared to C (p < 0.001), but only IL-6 is higher than SA (p < 0.001). No differences are found in lipid and glucose assessment. After a 1YFU, patients with a history of UA improve their oxidative and inflammatory status, such as the levels of circulating ds-DNA, without achieving the status of C. They become comparable to SA subjects. This study provides new insight on the multiple and apparently contradictory facets of NF-kB in UA and on its possible role as mediator in NETs' formation.

Cardiovascular disease in systemic lupus erythematosus: A comprehensive update

Heightened rates of both cardiovascular (CV) events and subclinical atherosclerosis, documented by imaging and vascular function techniques are well established in systemic lupus erythematosus (SLE). While traditional CV factors such as smoking, dyslipidemia, diabetes mellitus (DM), hypertension, central obesity and hyperhomocysteinemia have been reported to be prevalent in lupus patients, they do not fully explain the high rates of ischemic events so far reported, implying that other factors inherent to disease itself could account for the enhanced risk, including disease duration, activity and chronicity, psychosocial factors, medications, genetic variants and altered immunological mechanisms. Though the exact pathogenesis of atherosclerosis in the setting of lupus remains ill defined, an imbalance between endothelial damage and atheroprotection seems to be a central event. Insults leading to endothelial damage in the setting of lupus include oxidized low density lipoprotein (oxLDL), autoantibodies against endothelial cells and phospholipids, type I interferons (IFN) and neutrophil extracellular traps (NETs) directly or through activation of type I IFN pathway. Increased oxidative stress, reduced levels of the normally antioxidant high density lipoprotein (HDL), increased levels of proinflammatory HDL (piHDL) and reduced paraoxonase activity have been related to increased oxLDL levels. On the other hand, impaired atheroprotective mechanisms in lupus include decreased capacity of endothelial repair-partly mediated by type I IFN- and dampened production of atheroprotective autoantibodies. In the present review, traditional and disease related risk factors for CV disease (CVD) in the setting of chronic autoimmune disorders with special focus on SLE will be discussed.