NLRP3-Induced NETosis: A Potential Therapeutic Target for Ischemic Thrombotic Diseases?

Pathological roles of NETs-platelet synergy in thrombotic diseases: From molecular mechanisms to therapeutic targeting

The formation of neutrophil extracellular traps (NETs) is a novel way for neutrophils to perform organismal protective functions essential for protecting the host against infections. Nevertheless, an increasing amount of data shows that uncontrolled or excessive formation of NETs in the body leads to inflammation and thrombosis. Many serious human diseases, such as sepsis, stroke, cancer, and autoimmune diseases, are associated with thrombosis, and inhibiting its formation is essential to prevent the development of many inflammatory and thrombotic diseases. With deeper research, it has been found that there is a complex interaction between NETs and platelets: platelets activate neutrophils to form NETs, while NET components enhance platelet aggregation and activation. This self-perpetuating vicious cycle between them mediates pathological processes such as inflammation, coagulation, and thrombosis. A deeper comprehension of the underlying molecular mechanisms between them promises to be a new target for thrombotic diseases. In this review, we concentrate on a summary of NET formation and its mechanisms of action. Providing a thorough summary of how neutrophils are activated by platelets to form NETs, how NETs cause platelet activation, and how this close interaction during inflammatory events affects the course of the disease, with the aim of providing fresh targets and ideas for thrombotic disease clinical prevention and therapy.

Non-T2 asthma

PURPOSE OF REVIEW

This review provides a comprehensive overview of the non-T asthma phenotypes. Asthma is an umbrella term that defines a complex group of heterogenous airway disorders, which are broadly categorized into predominantly T2 or non-T2 phenotypes depending on the presence and levels of airway and systemic biomarkers associated with a T2 inflammatory response. Individuals with predominant T2 asthma have greater numbers of peripheral blood eosinophils, exhaled nitric oxide and IgE. These patients have more atopy and earlier onset asthma. In contrast, the absence or low levels of these biomarkers define non-T2 asthma. This is a heterogenous group with a later onset of asthma that is also more commonly associated with obesity and with females.

RECENT FINDINGS

This article summarizes new information regarding the plasticity that exists between T2 and non-T2 mechanisms, including their role in exacerbation-prone and nonexacerbating asthma, and many of the risk factors associated with the non-T2 phenotype, such as viral infections, ambient air pollution exposure, smoking, genetic and metabolic factors. It also provides new information on the immunological and metabolic mechanisms associated with non-T2 asthma. We also discuss how to manage this asthma phenotype and how treatment responses differ for these patients.

SUMMARY

Non-T2 asthma defines a heterogenous group of asthma phenotypes. However, acknowledging that the absence of T2 biomarkers is influenced by several factors is important and can longitudinally change in relation to exacerbations, particularly in children.

Research trends on neutrophil extracellular traps in ischemic stroke: a scientific metrology study

Background

Ischemic stroke (IS) remains a leading global cause of mortality and chronic disability. Neutrophil extracellular traps (NETs), recently identified as neutrophil-derived structures that trap and neutralize pathogens, have increasingly drawn attention for their involvement in IS pathogenesis. Despite a surge in related research, no bibliometric analyses have yet examined the knowledge framework and trends within this emerging field. Here, we conducted a systematic bibliometric analysis to map the research landscape and identify current and potential hotspots regarding NETs in IS.

Methods

Relevant literature published between 2014 and 2024 was systematically retrieved from the Web of Science Core Collection (WoSCC) database. Multiple analytical tools, including CiteSpace, VOSviewer, R package "bibliometrix," and Python scripts, were employed to explore publication trends, academic collaborations, prominent research themes, and emerging topics.

Results

Ninety-two publications were eligible for bibliometric assessment, supplemented by an additional latent Dirichlet allocation (LDA)-based topic analysis of 4,504 documents. China (30 publications) and the United States (23 publications) emerged as leading countries in terms of research output, with global collaboration networks predominantly centering around the United States. Noteworthy contributions also arose from European institutions, particularly Katholieke Universiteit Leuven and Karolinska Institutet. The leading authors identified were Desilles, Jean-Philippe, Ho-Tin-Noé, Benoit, and Mazighi, Mikael. Journals such as Stroke, Annals of Neurology, and Nature Communications significantly influenced this domain. Three main research hotspots emerged: (1) "promoting effect of protein arginine deiminase 4 (PAD4) in NET formation," (2) "cell-free DNA as a biomarker for disease diagnosis," and (3) "influence of platelets and thrombosis on NETs-related diseases."

Conclusion

Our study offers an extensive overview of existing literature and evolving research trajectories concerning NETs in IS, providing researchers with clear insights into current trends and future investigative directions. Nevertheless, our study has limitations-including dependence on a single database (WoSCC), restriction to English-language publications, and inherent constraints of the LDA methodology-that merit consideration in interpreting these findings.

Inflammasomes and idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIM) are a group of systemic autoimmune diseases characterized by muscle weakness and elevated serum creatine kinase levels. Recent research has highlighted the role of the innate immune system, particularly inflammasomes, in the pathogenesis of IIM. This review focuses on the role of inflammasomes, specifically NLRP3 and AIM2, and their associated proteins in the development of IIM. We discuss the molecular mechanisms of pyroptosis, a programmed cell death pathway that triggers inflammation, and its association with IIM. The NLRP3 inflammasome, in particular, has been implicated in muscle fiber necrosis and the subsequent release of damage-associated molecular patterns (DAMPs), leading to inflammation. We also explore the potential therapeutic implications of targeting the NLRP3 inflammasome with inhibitors such as glyburide and MCC950, which have shown promise in reducing inflammation and improving muscle function in preclinical models. Additionally, we discuss the role of caspases, particularly caspase-1, in the canonical pyroptotic pathway associated with IIM. The understanding of these mechanisms offers new avenues for therapeutic intervention and a better comprehension of IIM pathophysiology.

Deep-Learning-Driven Discovery of SN3-1, a Potent NLRP3 Inhibitor with Therapeutic Potential for Inflammatory Diseases

The NLRP3 inflammasome plays a central role in the pathogenesis of various intractable human diseases, making it an urgent target for therapeutic intervention. Here, we report the development of SN3-1, a novel orally potent NLRP3 inhibitor, designed through a lead compound strategy centered on deep-learning-based molecular generative models. Our strategy enables rapid fragment enumeration and takes into account the synthetic accessibility of the compounds, thereby significantly enhancing the optimization of lead compounds and facilitating the discovery of potent inhibitors. X-ray crystallography provided insights into the SN3-1 inhibitory mechanism. SN3-1 has shown a favorable safety profile in both acute and chronic toxicity assessments and exhibits robust pharmacokinetic properties. Furthermore, SN3-1 demonstrated significant therapeutic efficacy in various disease models characterized by NLRP3 activation. This study introduces a potent candidate for developing NLRP3 inhibitors and significantly expands the repertoire of tools available for the discovery of novel inhibitors.

Nets in fibrosis: Bridging innate immunity and tissue remodeling

Fibrosis, a complex pathological process characterized by excessive deposition of extracellular matrix components, leads to tissue scarring and dysfunction. Emerging evidence suggests that neutrophil extracellular traps (NETs), composed of DNA, histones, and antimicrobial proteins, significantly contribute to fibrotic diseases pathogenesis. This review summarizes the process of NETs production, molecular mechanisms, and related diseases, and outlines the cellular and molecular mechanisms associated with fibrosis. Subsequently, this review comprehensively summarizes the current understanding of the intricate interplay between NETs and fibrosis across various organs, including the lung, liver, kidney, skin, and heart. The mechanisms by which NETs contribute to fibrogenesis, including their ability to promote inflammation, induce epithelial-mesenchymal transition (EMT), activate fibroblasts, deposit extracellular matrix (ECM) components, and trigger TLR4 signaling were explored. This review aimed to provide insights into the complex relationship between NETs and fibrosis via a comprehensive analysis of existing reports, offering novel perspectives for future research and therapeutic interventions.

Implication of the LRR Domain in the Regulation and Activation of the NLRP3 Inflammasome

The NLRP3 inflammasome is a critical component of the innate immune response. NLRP3 activation is a tightly controlled process involving an initial priming to express NLRP3, pro-IL-1 β, and pro-IL-18, followed by an activation signal. The precise mechanism of activation is not fully understood due to the diverse range of activators, yet it effectively orchestrates the activation of caspase-1, which subsequently triggers the release of proinflammatory cytokines IL-1β and IL-18. NLRP3 dysregulation can lead to a variety of inflammatory diseases, highlighting its significant role in immune response and disease pathogenesis. NLRP3 is divided into three domains: the PYD, the NACHT, and the LRR domains. This review focuses on the LRR domain of NLRP3, detailing its structural characteristics, its function in pathogen sensing, its role in the degradation process, and its involvement in inflammasome auto-inhibition and activation. Additionally, we discuss the impact of mutations within the LRR domain found in atypical Cryopyrin-Associated Periodic Syndromes (CAPS), highlighting the clinical relevance of this domain.

Role of deubiquitinase USP47 in cardiac function alleviation and anti-inflammatory immunity after myocardial infarction by regulating NLRP3 inflammasome-mediated pyroptotic signal pathways

Myocardial infarction (MI) is an event of heart attack due to the formation of plaques in the interior walls of the arteries. This study is conducted to explore the role of ubiquitin-specific peptidase 47 (USP47) in cardiac function and inflammatory immunity. MI mouse models were established, followed by an appraisal of cardiac functions, infarct size, pathological changes, and USP47 and NLRP3 levels. MI cell models were established in HL-1 cells using anoxia. Levels of cardiac function-associated proteins, USP7, interferon regulatory factor 1 (IRF1), platelet factor-4 (CXCL4), pyroptotic factors, and neutrophil extracellular traps (NETs) were determined. The bindings of IRF1 to USP47 and the CXCL4 promoter and the ubiquitination of IRF1 were analyzed. USP47 was upregulated in myocardial tissues of MI mice. USP47 inhibition alleviated cardiac functions, and decreased infarct size, pro-inflammatory cytokines, NETs, NLRP3, and pyroptosis. The ubiquitination and expression levels of IRF1 were increased by silencing USP47, and IRF1 bound to the CXCL4 promoter to promote CXCL4. Overexpression of IRF1 or CXCL4 in vitro and injection of Nigericin in vivo reversed the effect of silencing USP47 on alleviating pyroptosis and cardiac functions. Collectively, USP47 stabilized IRF1 and promoted CXCL4, further promoting pyroptosis, impairing cardiac functions, and aggravating immune inflammation through NLRP3 pathways.

A promising frontier: targeting NETs for stroke treatment breakthroughs

Stroke is a prevalent global acute cerebrovascular condition, with ischaemic stroke being the most frequently occurring type. After a stroke, neutrophils accumulate in the brain and subsequently generate and release neutrophil extracellular traps (NETs). The accumulation of NETs exacerbates the impairment of the blood‒brain barrier (BBB), hampers neovascularization, induces notable neurological deficits, worsens the prognosis of stroke patients, and can facilitate the occurrence of t-PA-induced cerebral haemorrhage subsequent to ischaemic stroke. Alternative approaches to pharmacological thrombolysis or endovascular thrombectomy are being explored, and targeting NETs is a promising treatment that warrants further investigation.