VX-765 attenuates atherosclerosis in ApoE deficient mice by modulating VSMCs pyroptosis

Recent Advances in Targeted Management of Inflammation In Atherosclerosis: A Narrative Review

Atherosclerotic cardiovascular disease (ASCVD) remains a leading cause of morbidity and mortality despite effective low-density lipoprotein cholesterol-targeted therapies. This review explores the crucial role of inflammation in the residual risk of ASCVD, emphasizing its impact on atherosclerosis progression and plaque stability. Evidence suggests that high-sensitivity C-reactive protein (hsCRP), and potentially other inflammatory biomarkers, can be used to identify the inflammatory residual ASCVD risk phenotype and may serve as future targets for the development of more efficacious therapeutic approaches. We review the biological basis for the association of inflammation with ASCVD, propose new therapeutic strategies for the use of inflammation-targeted treatments, and discuss current challenges in the implementation of this new treatment paradigm for ASCVD.

Inhibition of Caspase-1-dependent pyroptosis alleviates myocardial ischemia/reperfusion injury during cardiopulmonary bypass (CPB) in type 2 diabetic rats

Cardiovascular complications pose a significant burden in type 2 diabetes mellitus (T2DM), driven by the intricate interplay of chronic hyperglycemia, insulin resistance, and lipid metabolism disturbances. Myocardial ischemia/reperfusion (MI/R) injury during cardiopulmonary bypass (CPB) exacerbates cardiac vulnerability. This study aims to probe the role of Caspase-1-dependent pyroptosis in global ischemia/reperfusion injury among T2DM rats undergoing CPB, elucidating the mechanisms underlying heightened myocardial injury in T2DM. This study established a rat model of T2DM and compared Mean arterial pressure (MAP), heart rate (HR), and hematocrit (Hct) between T2DM and normal rats. Myocardial cell morphology, infarction area, mitochondrial ROS and caspase-1 levels, NLRP3, pro-caspase-1, caspase-1 p10, GSDMD expressions, plasma CK-MB, cTnI, IL-1β, and IL-18 levels were assessed after reperfusion in both T2DM and normal rats. The role of Caspase-1-dependent pyroptosis in myocardial ischemia/reperfusion injury during CPB in T2DM rats was examined using the caspase-1 inhibitor VX-765 and the ROS scavenger NAC. T2DM rats demonstrated impaired glucose tolerance but stable hemodynamics during CPB, while showing heightened vulnerability to MI/R injury. This was marked by substantial lipid deposition, disrupted myocardial fibers, and intensified cellular apoptosis. The activation of caspase-1-mediated pyroptosis and increased reactive oxygen species (ROS) production further contributed to tissue damage and the ensuing inflammatory response. Notably, myocardial injury was mitigated by inhibiting caspase-1 through VX-765, which also attenuated the inflammatory cascade. Likewise, NAC treatment reduced oxidative stress and partially suppressed ROS-mediated caspase-1 activation, resulting in diminished myocardial injury. This study proved that Caspase-1-dependent pyroptosis significantly contributes to the inflammation and injury stemming from global MI/R in T2DM rats under CPB, which correlate with the surplus ROS generated by oxidative stress during reperfusion.

Oxidative Stress-Mediated Programmed Cell Death: a Potential Therapy Target for Atherosclerosis

Nowadays, as a type of orderly and active death determined by genes, programmed cell death (PCD), including apoptosis, pyroptosis, ferroptosis, and necroptosis, has attracted much attention owing to its participation in numerous chronic cardiovascular diseases, especially atherosclerosis (AS), a canonical chronic inflammatory disease featured by lipid metabolism disturbance. Abundant researches have reported that PCD under distinct internal conditions fulfills different roles of atherosclerotic pathological processes, including lipid core expansion, leukocyte adhesion, and infiltration. Noteworthy, emerging evidence recently has also suggested that oxidative stress (OS), an imbalance of antioxidants and oxygen free radicals, has the potential to mediate PCD occurrence via multiple ways, including oxidization and deubiquitination. Interestingly, more recently, several studies have proposed that the mediating mechanisms could effect on the atherosclerotic initiation and progression significantly from variable aspects, so it is of great clinical importance to clarify how OS-mediated PCD and AS interact. Herein, with the aim of summarizing potential and sufficient atherosclerotic therapy targets, we seek to provide extensive analysis of the specific regulatory mechanisms of PCD mediated by OS and their multifaceted effects on the entire pathological atherosclerotic progression.

Challenges and advances in the management of inflammation in atherosclerosis

INTRODUCTION

Atherosclerosis, traditionally considered a lipid-related disease, is now understood as a chronic inflammatory condition with significant global health implications.

OBJECTIVES

This review aims to delve into the complex interactions among immune cells, cytokines, and the inflammatory cascade in atherosclerosis, shedding light on how these elements influence both the initiation and progression of the disease.

METHODS

This review draws on recent clinical research to elucidate the roles of key immune cells, macrophages, T cells, endothelial cells, and clonal hematopoiesis in atherosclerosis development. It focuses on how these cells and process contribute to disease initiation and progression, particularly through inflammation-driven processes that lead to plaque formation and stabilization. Macrophages ingest oxidized low-density lipoprotein (oxLDL), which partially converts to high-density lipoprotein (HDL) or accumulates as lipid droplets, forming foam cells crucial for plaque stability. Additionally, macrophages exhibit diverse phenotypes within plaques, with pro-inflammatory types predominating and others specializing in debris clearance at rupture sites. The involvement of CD4+ T and CD8+ T cells in these processes promotes inflammatory macrophage states, suppresses vascular smooth muscle cell proliferation, and enhances plaque instability.

RESULTS

The nuanced roles of macrophages, T cells, and the related immune cells within the atherosclerotic microenvironment are explored, revealing insights into the cellular and molecular pathways that fuel inflammation. This review also addresses recent advancements in imaging and biomarker technology that enhance our understanding of disease progression. Moreover, it points out the limitations of current treatment and highlights the potential of emerging anti-inflammatory strategies, including clinical trials for agents such as p38MAPK, tumor necrosis factor α (TNF-α), and IL-1β, their preliminary outcomes, and the promising effects of canakinumab, colchicine, and IL-6R antagonists.

CONCLUSION

This review explores cutting-edge anti-inflammatory interventions, their potential efficacy in preventing and alleviating atherosclerosis, and the role of nanotechnology in delivering drugs more effectively and safely.

Regulated vascular smooth muscle cell death in vascular diseases

Regulated cell death (RCD) is a complex process that involves several cell types and plays a crucial role in vascular diseases. Vascular smooth muscle cells (VSMCs) are the predominant elements of the medial layer of blood vessels, and their regulated death contributes to the pathogenesis of vascular diseases. The types of regulated VSMC death include apoptosis, necroptosis, pyroptosis, ferroptosis, parthanatos, and autophagy-dependent cell death (ADCD). In this review, we summarize the current evidence of regulated VSMC death pathways in major vascular diseases, such as atherosclerosis, vascular calcification, aortic aneurysm and dissection, hypertension, pulmonary arterial hypertension, neointimal hyperplasia, and inherited vascular diseases. All forms of RCD constitute a single, coordinated cell death system in which one pathway can compensate for another during disease progression. Pharmacologically targeting RCD pathways has potential for slowing and reversing disease progression, but challenges remain. A better understanding of the role of regulated VSMC death in vascular diseases and the underlying mechanisms may lead to novel pharmacological developments and help clinicians address the residual cardiovascular risk in patients with cardiovascular diseases.

The cytoplasmic sensor, the AIM2 inflammasome: A precise therapeutic target in vascular and metabolic diseases

Cardio-cerebrovascular diseases encompass pathological changes in the heart, brain and vascular system, which pose a great threat to health and well-being worldwide. Moreover, metabolic diseases contribute to and exacerbate the impact of vascular diseases. Inflammation is a complex process that protects against noxious stimuli but is also dysregulated in numerous so-called inflammatory diseases, one of which is atherosclerosis. Inflammation involves multiple organ systems and a complex cascade of molecular and cellular events. Numerous studies have shown that inflammation plays a vital role in cardio-cerebrovascular diseases and metabolic diseases. The absent in melanoma 2 (AIM2) inflammasome detects and is subsequently activated by double-stranded DNA in damaged cells and pathogens. With the assistance of the mature effector molecule caspase-1, the AIM2 inflammasome performs crucial biological functions that underpin its involvement in cardio-cerebrovascular diseases and related metabolic diseases: The production of interleukin-1 beta (IL-1β), interleukin-18 (IL-18) and N-terminal pore-forming Gasdermin D fragment (GSDMD-N) mediates a series of inflammatory responses and programmed cell death (pyroptosis and PANoptosis). Currently, several agents have been reported to inhibit the activity of the AIM2 inflammasome and have the potential to be evaluated for use in clinical settings. In this review, we systemically elucidate the assembly, biological functions, regulation and mechanisms of the AIM2 inflammasome in cardio-cerebrovascular diseases and related metabolic diseases and outline the inhibitory agents of the AIM2 inflammasome as potential therapeutic drugs.

Pyroptosis of Vascular Smooth Muscle Cells as a Potential New Target for Preventing Vascular Diseases

Vascular remodeling is the adaptive response of the vessel wall to physiological and pathophysiological changes, closely linked to vascular diseases. Vascular smooth muscle cells (VSMCs) play a crucial role in this process. Pyroptosis, a form of programmed cell death characterized by excessive release of inflammatory factors, can cause phenotypic transformation of VSMCs, leading to their proliferation, migration, and calcification-all of which accelerate vascular remodeling. Inhibition of VSMC pyroptosis can delay this process. This review summarizes the impact of pyroptosis on VSMCs and the pathogenic role of VSMC pyroptosis in vascular remodeling. We also discuss inhibitors of key proteins in pyroptosis pathways and their effects on VSMC pyroptosis. These findings enhance our understanding of the pathogenesis of vascular remodeling and provide a foundation for the development of novel medications that target the control of VSMC pyroptosis as a potential treatment strategy for vascular diseases.

Programmed death of macrophages in atherosclerosis: mechanisms and therapeutic targets

Atherosclerosis is a progressive inflammatory disorder of the arterial vessel wall characterized by substantial infiltration of macrophages, which exert both favourable and detrimental functions. Early in atherogenesis, macrophages can clear cytotoxic lipoproteins and dead cells, preventing cytotoxicity. Efferocytosis - the efficient clearance of dead cells by macrophages - is crucial for preventing secondary necrosis and stimulating the release of anti-inflammatory cytokines. In addition, macrophages can promote tissue repair and proliferation of vascular smooth muscle cells, thereby increasing plaque stability. However, advanced atherosclerotic plaques contain large numbers of pro-inflammatory macrophages that secrete matrix-degrading enzymes, induce death in surrounding cells and contribute to plaque destabilization and rupture. Importantly, macrophages in the plaque can undergo apoptosis and several forms of regulated necrosis, including necroptosis, pyroptosis and ferroptosis. Regulated necrosis has an important role in the formation and expansion of the necrotic core during plaque progression, and several triggers for necrosis are present within atherosclerotic plaques. This Review focuses on the various forms of programmed macrophage death in atherosclerosis and the pharmacological interventions that target them as a potential means of stabilizing vulnerable plaques and improving the efficacy of currently available anti-atherosclerotic therapies.

Screening and validation of atherosclerosis PAN-apoptotic immune-related genes based on single-cell sequencing

Background

Carotid atherosclerosis (CAS) is a complication of atherosclerosis (AS). PAN-optosome is an inflammatory programmed cell death pathway event regulated by the PAN-optosome complex. CAS's PAN-optosome-related genes (PORGs) have yet to be studied. Hence, screening the PAN-optosome-related diagnostic genes for treating CAS was vital.

Methods

We introduced transcriptome data to screen out differentially expressed genes (DEGs) in CAS. Subsequently, WGCNA analysis was utilized to mine module genes about PANoptosis score. We performed differential expression analysis (CAS samples vs. standard samples) to obtain CAS-related differentially expressed genes at the single-cell level. Venn diagram was executed to identify PAN-optosome-related differential genes (POR-DEGs) associated with CAS. Further, LASSO regression and RF algorithm were implemented to were executed to build a diagnostic model. We additionally performed immune infiltration and gene set enrichment analysis (GSEA) based on diagnostic genes. We verified the accuracy of the model genes by single-cell nuclear sequencing and RT-qPCR validation of clinical samples, as well as in vitro cellular experiments.

Results

We identified 785 DEGs associated with CAS. Then, 4296 module genes about PANoptosis score were obtained. We obtained the 7365 and 1631 CAS-related DEGs at the single-cell level, respectively. 67 POR-DEGs were retained Venn diagram. Subsequently, 4 PAN-optosome-related diagnostic genes (CNTN4, FILIP1, PHGDH, and TFPI2) were identified via machine learning. Cellular function tests on four genes showed that these genes have essential roles in maintaining arterial cell viability and resisting cellular senescence.

Conclusion

We obtained four PANoptosis-related diagnostic genes (CNTN4, FILIP1, PHGDH, and TFPI2) associated with CAS, laying a theoretical foundation for treating CAS.

Preparation of VX765 sodium alginate nanogels and evaluation of their therapeutic effect via local injection on myocardial infarction in rats

Myocardial Infarction (MI) is major cause of heart failure, highlighting the critical need for effective therapeutic strategies to improve cardiac repair. This study investigated the cardioprotective effects of VX765-coated polyethyleneimine (PEI)/sodium alginate (AG) composite nanogels (AG/PEI-VX765 NGs) in a rat model of MI. Additionally, AG-VX765 NGs and PEI-VX765 nanospheres (NPs) were synthesized and tested to compare their efficacy. MI was caused in rats by ligating the left anterior descending branch of the coronary artery, and the rats were grouped and set as Sham, MI, MI + VX765, MI + AG-VX765NGs, MI + PEI-VX765NPs, and MI + AG/PEI-VX765NGs. Results demonstrate that AG/PEI-VX765NGs were non-toxic and exhibited a sustained release of VX765. In vivo, experiments demonstrated that all treatment groups significantly enhanced cardiac function, reduced infarct size, fibrosis, and apoptosis in rats with MI, with the MI + AG/PEI-VX765NGs group exhibiting the most favorable outcomes. Our findings indicate that AG/PEI-VX765NGs represent a promising therapeutic approach for MI treatment.

Cell death in atherosclerosis

A complex and evolutionary process that involves the buildup of lipids in the arterial wall and the invasion of inflammatory cells results in atherosclerosis. Cell death is a fundamental biological process that is essential to the growth and dynamic equilibrium of all living things. Serious cell damage can cause a number of metabolic processes to stop, cell structure to be destroyed, or other irreversible changes that result in cell death. It is important to note that studies have shown that the two types of programmed cell death, apoptosis and autophagy, influence the onset and progression of atherosclerosis by controlling these cells. This could serve as a foundation for the creation of fresh atherosclerosis prevention and treatment strategies. Therefore, in this review, we summarized the molecular mechanisms of cell death, including apoptosis, pyroptosis, autophagy, necroptosis, ferroptosis and necrosis, and discussed their effects on endothelial cells, vascular smooth muscle cells and macrophages in the process of atherosclerosis, so as to provide reference for the next step to reveal the mechanism of atherosclerosis.

New Insights on NLRP3 Inflammasome: Mechanisms of Activation, Inhibition, and Epigenetic Regulation

Inflammasomes are important modulators of inflammation. Dysregulation of inflammasomes can enhance vulnerability to conditions such as neurodegenerative diseases, autoinflammatory diseases, and metabolic disorders. Among various inflammasomes, Nucleotide-binding oligomerization domain leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) is the best-characterized inflammasome related to inflammatory and neurodegenerative diseases. NLRP3 is an intracellular sensor that recognizes pathogen-associated molecular patterns and damage-associated patterns resulting in the assembly and activation of NLRP3 inflammasome. The NLRP3 inflammasome includes sensor NLRP3, adaptor apoptosis-associated speck-like protein (ASC), and effector cysteine protease procaspase-1 that plays an imperative role in caspase-1 stimulation which further initiates a secondary inflammatory response. Regulation of NLRP3 inflammasome ameliorates NLRP3-mediated diseases. Much effort has been invested in studying the activation, and exploration of specific inhibitors and epigenetic mechanisms controlling NLRP3 inflammasome. This review gives an overview of the established NLRP3 inflammasome assembly, its brief molecular mechanistic activations as well as a current update on specific and non-specific NLRP3 inhibitors that could be used in NLRP3-mediated diseases. We also focused on the recently discovered epigenetic mechanisms mediated by DNA methylation, histone alterations, and microRNAs in regulating the activation and expression of NLRP3 inflammasome, which has resulted in a novel method of gaining insight into the mechanisms that modulate NLRP3 inflammasome activity and introducing potential therapeutic strategies for CNS disorders.

Pathological and Therapeutical Implications of Pyroptosis in Psoriasis and Hidradenitis Suppurativa: A Narrative Review

This manuscript explores the role of pyroptosis, an inflammatory programmed cell death, in the pathogenesis of two chronic dermatoses, psoriasis and hidradenitis suppurativa (HS). The diseases, though clinically diverse, share common pathogenetic pathways involving the unbalanced interaction between the adaptive and innate immune systems. This review focuses on the molecular changes in psoriatic and HS skin, emphasizing the activation of dendritic cells, secretion of interleukins (IL-17, IL-22, and TNF-α), and the involvement of inflammasomes, particularly NLRP3. This manuscript discusses the role of caspases, especially caspase-1, in driving pyroptosis and highlights the family of gasdermins (GSDMs) as key players in the formation of pores leading to cell rupture and the release of proinflammatory signals. This study delves into the potential therapeutic implications of targeting pyroptosis in psoriasis and HS, examining existing medications like biologics and Janus kinase inhibitors. It also reviews the current limitations and challenges in developing therapies that selectively target pyroptosis. Additionally, the manuscript explores the role of pyroptosis in various inflammatory disorders associated with psoriasis and HS, such as inflammatory bowel disease, diabetes mellitus, and cardiovascular disorders. The review concludes by emphasizing the need for further research to fully elucidate the pathomechanisms of these dermatoses and develop effective, targeted therapies.

The NLRP3 Inflammasome as a Pathogenic Player Showing Therapeutic Potential in Rheumatoid Arthritis and Its Comorbidities: A Narrative Review

Rheumatoid arthritis (RA) is an autoimmune inflammatory disease characterized by chronic synovitis and the progressive destruction of cartilage and bone. RA is commonly accompanied by extra-articular comorbidities. The pathogenesis of RA and its comorbidities is complex and not completely elucidated. The assembly of the NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasome activates caspase-1, which induces the maturation of interleukin (IL)-1β and IL-18 and leads to the cleavage of gasdermin D with promoting pyroptosis. Accumulative evidence indicates the pathogenic role of NLRP3 inflammasome signaling in RA and its comorbidities, including atherosclerotic cardiovascular disease, osteoporosis, and interstitial lung diseases. Although the available therapeutic agents are effective for RA treatment, their high cost and increased infection rate are causes for concern. Recent evidence revealed the components of the NLRP3 inflammasome as potential therapeutic targets in RA and its comorbidities. In this review, we searched the MEDLINE database using the PubMed interface and reviewed English-language literature on the NLRP3 inflammasome in RA and its comorbidities from 2000 to 2023. The current evidence reveals that the NLRP3 inflammasome contributes to the pathogenesis of RA and its comorbidities. Consequently, the components of the NLRP3 inflammasome signaling pathway represent promising therapeutic targets, and ongoing research might lead to the development of new, effective treatments for RA and its comorbidities.

Cathepsin B aggravates atherosclerosis in ApoE-deficient mice by modulating vascular smooth muscle cell pyroptosis through NF-κB / NLRP3 signaling pathway

Atherosclerosis (AS) is a chronic inflammatory disease involving cell death and inflammatory responses. Pyroptosis, a newly discovered pro-inflammatory programmed cell death process, exacerbates inflammatory responses. However, the roles of cathepsin B (CTSB) in pyroptosis and AS remain unclear. To gain further insight, we fed ApoE-/- mice a high-fat diet to investigate the effects and mechanisms of CTSB overexpression and silencing on AS. We also explored the specific role of CTSB in vascular smooth muscle cells (VSMCs) in vitro. The study revealed that high-fat diet led to the formation of AS plaques, and CTSB was found to increase the AS plaque lesion area. Immunohistochemical and TUNEL/caspase-1 staining revealed the existence of pyroptosis in atherosclerotic plaques, particularly in VSMCs. In vitro studies, including Hoechst 33342/propidium iodide staining, a lactate dehydrogenase (LDH) release assay, detection of protein indicators of pyroptosis, and detection of interleukin-1β (IL-1β) in cell culture medium, demonstrated that oxidized low-density lipoprotein (ox-LDL) induced VSMC pyroptosis. Additionally, CTSB promoted VSMC pyroptosis. Ox-LDL increased the expression of CTSB, which in turn activated the NOD-like receptor protein 3 (NLRP3) inflammasome and promoted NLRP3 expression by facilitating nuclear factor kappa B (NF-κB) p65 nuclear translocation. This effect could be attenuated by the NF-κB inhibitor SN50. Our research found that CTSB not only promotes VSMC pyroptosis by activating the NLRP3 inflammasome, but also increases the expression of NLRP3.

Vasculitis and the NLRP3 inflammasome

PURPOSE OF REVIEW

Vasculitis are a group of heterogeneous conditions characterized by chronic inflammation of blood vessels, leading to tissue destruction and organ failure. Vasculitis is an inflammatory process in which immune effector cells infiltrate blood vessels and surrounding tissues. The involvement of inflammasomes seems to occur during inflammatory processes.

RECENT FINDINGS

Studies have emphasized that genetic susceptibility is an important aspect of the pathogenesis of vasculitis. The innate immune system is a major contributor to these inflammatory diseases, suggesting that the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome plays a key role. NLRP3 activation causes the assembly of a large multiprotein and leads to the secretion of bioactive interleukin (IL)-1β and IL-18 as well as the induction of inflammatory cell death, termed pyroptosis. Accumulating evidence confirms the involvement of this cascade in sterile inflammatory diseases and other vascular diseases.

SUMMARY

In this review, we will summarize the current state of knowledge regarding the role of NLRP3 inflammasome in vascular diseases, and discuss the potential of the NLRP3 inflammasome as a therapeutic target.

Phlorizin ameliorates myocardial fibrosis by inhibiting pyroptosis through restraining HK1-mediated NLRP3 inflammasome activation

The specific role of phlorizin (PHL), which has antioxidant, anti-inflammatory, hypoglycemic, antiarrhythmic and antiaging effects, on myocardial fibrosis (MF) and the related pharmacological mechanisms remain unknown. The objective of this study was to determine the protective actions of PHL on isoprenaline (ISO)-induced MF and its molecular mechanisms in mice. PHL was administered at 100 and 200 mg/kg for 15 consecutive days with a subcutaneous injection of ISO (10 mg/kg). MF was induced by ISO and alleviated by treatment with PHL, as shown by reduced fibrin accumulation in the myocardial interstitium and decreased levels of myocardial enzymes, such as creatinine kinase-MB, lactate dehydrogenase, and aspartate transaminase. In addition, PHL significantly decreased the expression of the fibrosis-related factors alpha smooth muscle actin, collagen I, and collagen III induced by ISO. The generation of intracellular reactive oxygen species induced by ISO was attenuated after PHL treatment. The malondialdehyde level was reduced, whereas the levels of superoxide dismutase, catalase, and glutathione were elevated with PHL administration. Moreover, compared to ISO, the level of Bcl-2 was increased and the level of Bax protein was decreased in the PHL groups. PHL relieved elevated TNF-α, IL-1β, and IL-18 levels as well as cardiac mitochondrial damage resulting from ISO. Further studies showed that PHL downregulated the high expression of hexokinase 1 (HK1), NLRP3, ASC, Caspase-1, and GSDMD-N caused by ISO. In conclusion, our findings suggest that PHL protects against ISO-induced MF due to its antioxidant, anti-apoptotic, and anti-inflammatory activities and via inhibition of pyroptosis mediated by the HK1/NLRP3 signaling pathway in vivo.

MgCl2 Attenuates ox-LDL-Induced Vascular Smooth Muscle-Derived Foam Cells Pyroptosis by Downregulating the TLR4/NF-κB Signaling Pathway

Pyroptosis is a type of programmed cell death that is generally upregulated during atherosclerosis (AS). Magnesium, an important cation in the body, has exhibited an antiatherosclerotic effect. We collected AS model datasets from the Gene Expression Omnibus (GEO) and explored the correlation between pyroptosis and AS through a series of bioinformatics methods. We next investigated the impact of oxidized low-density lipoprotein (ox-LDL) on primary cultured vascular smooth muscle cells (VSMCs) foaminess and pyroptosis. Finally, foam cells were preconditioned with different concentrations of MgCl2 to explore its influence on ox-LDL-induced VSMCs pyroptosis. NLRP3-mediated pyroptosis plays a core role in regulating AS progression as shown by bioinformatic analysis. Ox-LDL (50/75/100 mg/L) increased CE/TE ratio (> 50%) in VSMCs and prompted VSMC-derived foam cell formation, and (75/100 mg/L) ox-LDL-induced pyroptosis. Compared to 1 mmol/L MgCl2, 10 mmol/L MgCl2 significantly downregulated the expression of pyroptosis related molecules in VSMCs induced by 75 mg/L ox-LDL, including NLRP3, ASC, caspase-1, and GSDMD. The secretion of IL-1β, IL-18, and LDH was also inhibited by MgCl2. According to CCK-8 and Hoechst 33,342/PI staining, the damage to VSMCs viability induced by ox-LDL was ameliorated by MgCl2. In addition, MgCl2 attenuated the upregulation of TLR4, IKKβ, and p65 and the downregulation of IκBα in VSMCs induced by ox-LDL. The present study demonstrated that pyroptosis-related genes were the core genes in AS. We also revealed the effect and underlying mechanism of MgCl2 on ox-LDL-induced VSMCs pyroptosis, suggesting that MgCl2 has promising clinical applications for AS pyroptosis prevention and treatment.

Roles of pyroptosis in atherosclerosis pathogenesis

Pyroptosis is a pro-inflammatory type of regulated cell death (RCD) characterized by gasdermin protein-mediated membrane pore formation, cell swelling, and rapid lysis. Recent studies have suggested that pyroptosis is closely related to atherosclerosis (AS). Previous studies reported that pyroptosis involving endothelial cells (ECs), macrophages, and smooth muscle cells (SMCs) plays an important role in the formation and development of AS. Pyroptosis not only causes local inflammation but also amplifies the inflammatory response and it aggravates plaque instability, leading to plaque rupture and thrombosis, eventually resulting in acute cardiovascular events. In this review, we clarified some novel pathways and mechanics and presented some potential drugs.

Pyroptosis in cardiovascular diseases: Pumping gasdermin on the fire

Pyroptosis is a form of programmed cell death associated with activation of inflammasomes and inflammatory caspases, proteolytic cleavage of gasdermin proteins (forming pores in the plasma membrane), and selective release of proinflammatory mediators. Induction of pyroptosis results in amplification of inflammation, contributing to the pathogenesis of chronic cardiovascular diseases such as atherosclerosis and diabetic cardiomyopathy, and acute cardiovascular events, such as thrombosis and myocardial infarction. While engagement of pyroptosis during sepsis-induced cardiomyopathy and septic shock is expected and well documented, we are just beginning to understand pyroptosis involvement in the pathogenesis of cardiovascular diseases with less defined inflammatory components, such as atrial fibrillation. Due to the danger that pyroptosis represents to cells within the cardiovascular system and the whole organism, multiple levels of pyroptosis regulation have evolved. Those include regulation of inflammasome priming, post-translational modifications of gasdermins, and cellular mechanisms for pore removal. While pyroptosis in macrophages is well characterized as a dramatic pro-inflammatory process, pyroptosis in other cell types within the cardiovascular system displays variable pathways and consequences. Furthermore, different cells and organs engage in local and distant crosstalk and exchange of pyroptosis triggers (oxidized mitochondrial DNA), mediators (IL-1β, S100A8/A9) and antagonists (IL-9). Development of genetic tools, such as Gasdermin D knockout animals, and small molecule inhibitors of pyroptosis will not only help us fully understand the role of pyroptosis in cardiovascular diseases but may result in novel therapeutic approaches inhibiting inflammation and progression of chronic cardiovascular diseases to reduce morbidity and mortality from acute cardiovascular events.

Inflammasomes in Atherosclerosis-From Pathophysiology to Treatment

Atherosclerosis, a chronic inflammatory disease characterized by arterial plaque accumulation, remains a significant global health challenge. In recent years, inflammasomes, the intracellular multiprotein complexes crucial for initiating innate immune responses, have emerged as key players in atherosclerosis pathophysiology. This review article aims to provide a comprehensive overview of the current understanding of inflammasome activation and its impact on atherosclerosis development and progression. We explore the intricate interplay between traditional cardiovascular risk factors and inflammasome activation, leading to the perpetuation of inflammatory cascades that drive plaque formation and instability. The review focuses on the molecular mechanisms underlying inflammasome activation, including the role of pattern recognition receptors and cytokines in this process. Moreover, we discuss the contribution of inflammasomes to endothelial dysfunction, foam cell formation, and vascular inflammation. Additionally, recent advances in therapeutic strategies targeting inflammasomes are examined, including pharmacological agents and potential immunomodulatory approaches. By collating and analyzing the current evidence, this review provides valuable insights into the potential of inflammasome-targeted therapies for atherosclerosis management and treatment. Understanding the pivotal role of inflammasomes in atherosclerosis pathophysiology offers promising prospects for developing effective and personalized therapeutic interventions that can mitigate the burden of this prevalent cardiovascular disorder and improve patient outcomes.

An Epstein-Barr virus protein interaction map reveals NLRP3 inflammasome evasion via MAVS UFMylation

Epstein-Barr virus (EBV) causes infectious mononucleosis, triggers multiple sclerosis, and is associated with 200,000 cancers/year. EBV colonizes the human B cell compartment and periodically reactivates, inducing expression of 80 viral proteins. However, much remains unknown about how EBV remodels host cells and dismantles key antiviral responses. We therefore created a map of EBV-host and EBV-EBV interactions in B cells undergoing EBV replication, uncovering conserved herpesvirus versus EBV-specific host cell targets. The EBV-encoded G-protein-coupled receptor BILF1 associated with MAVS and the UFM1 E3 ligase UFL1. Although UFMylation of 14-3-3 proteins drives RIG-I/MAVS signaling, BILF1-directed MAVS UFMylation instead triggered MAVS packaging into mitochondrial-derived vesicles and lysosomal proteolysis. In the absence of BILF1, EBV replication activated the NLRP3 inflammasome, which impaired viral replication and triggered pyroptosis. Our results provide a viral protein interaction network resource, reveal a UFM1-dependent pathway for selective degradation of mitochondrial cargo, and highlight BILF1 as a novel therapeutic target.

Role of pyroptosis in the pathogenesis and treatment of diseases

Programmed cell death (PCD) is regarded as a pathological form of cell death with an intracellular program mediated, which plays a pivotal role in maintaining homeostasis and embryonic development. Pyroptosis is a new paradigm of PCD, which has received increasing attention due to its close association with immunity and disease. Pyroptosis is a form of inflammatory cell death mediated by gasdermin that promotes the release of proinflammatory cytokines and contents induced by inflammasome activation. Recently, increasing evidence in studies shows that pyroptosis has a crucial role in inflammatory conditions like cardiovascular diseases (CVDs), cancer, neurological diseases (NDs), and metabolic diseases (MDs), suggesting that targeting cell death is a potential intervention for the treatment of these inflammatory diseases. Based on this, the review aims to identify the molecular mechanisms and signaling pathways related to pyroptosis activation and summarizes the current insights into the complicated relationship between pyroptosis and multiple human inflammatory diseases (CVDs, cancer, NDs, and MDs). We also discuss a promising novel strategy and method for treating these inflammatory diseases by targeting pyroptosis and focus on the pyroptosis pathway application in clinics.

Portrayal of NLRP3 Inflammasome in Atherosclerosis: Current Knowledge and Therapeutic Targets

We are witnessing the globalization of a specific type of arteriosclerosis with rising prevalence, incidence and an overall cardiovascular disease burden. Currently, atherosclerosis increasingly affects the younger generation as compared to previous decades. While early preventive medicine has seen improvements, research advances in laboratory and clinical investigation promise to provide us with novel diagnosis tools. Given the physio-pathological complexity and epigenetic patterns of atherosclerosis and the discovery of new molecules involved, the therapeutic field of atherosclerosis has room for substantial growth. Thus, the scientific community is currently investigating the role of nucleotide-binding and oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome, a crucial component of the innate immune system in different inflammatory disorders. NLRP3 is activated by distinct factors and numerous cellular and molecular events which trigger NLRP3 inflammasome assembly with subsequent cleavage of pro-interleukin (IL)-1β and pro-IL-18 pathways via caspase-1 activation, eliciting endothelial dysfunction, promotion of oxidative stress and the inflammation process of atherosclerosis. In this review, we introduce the basic cellular and molecular mechanisms of NLRP3 inflammasome activation and its role in atherosclerosis. We also emphasize its promising therapeutic pharmaceutical potential.

NLRP3 inflammasome pathway in atherosclerosis: Focusing on the therapeutic potential of non-coding RNAs

NLRP3 (NOD-, LRR-, and pyrin domain-containing protein 3) inflammasome pathway has a critical role in the pathogenesis of atherosclerosis. Activation of this pathway is implicated in the subendothelial inflammation and atherosclerosis progression. The NLRP3 inflammasome are cytoplasmic sensors with the distinct capacity to identify a wide range of inflammation-related signals, which enhance NLRP3 inflammasome assembly and allow it to trigger inflammation. This pathway is triggered by a variety of intrinsic signals which exist in atherosclerotic plaques, like cholesterol crystals and oxidized LDL. Further pharmacological findings indicated that NLRP3 inflammasome enhanced caspase-1-mediated secretion of pro-inflammatory mediators like interleukin (IL)- 1β/18. Newly published cutting-edge studies suggested that non-coding RNAs (ncRNAs) including microRNAs (miRNAs, miRs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) are major modulators of NLRP3 inflammasome in atherosclerosis. Therefore, in this review, we aimed to discuss the NLRP3 inflammasome pathway, biogenesis of ncRNAs as well as the modulatory role of ncRNAs in regulating the various mediators of NLRP3 inflammasome pathway including TLR4, NF-kB, NLRP3, and caspase 1. We also discussed the importance of NLRP3 inflammasome pathway-related ncRNAs as a diagnostic biomarker in atherosclerosis and current therapeutics in the modulation of NLRP3 inflammasome in atherosclerosis. Finally, we speak about the limitations and future prospects of ncRNAs in regulating inflammatory atherosclerosis via the NLRP3 inflammasome pathway.

VX-765 ameliorates CKD VSMC calcification by regulating STAT3 activation

BACKGROUND

Recent clinical evidences show that caspase-1 inhibitor-VX-765 attenuates atherosclerosis in ApoE deficient mice. However, there is rarely information about the effect of VX-765 on hyperphosphatemia-induced vascular smooth muscle cells (VSMCs) calcification or vascular calcification in chronic kidney disease (CKD) rats. Here we investigate the effect of VX-765 on vascular calcification in uremia circumstances.

METHODS

Hyperphosphatemia-induced VSMC calcification were evaluated by Alizarin Red S. Aortas from CKD rats which were gavaged with VX-765 were examined for calcification signal using micro-CT. Levels of NLRP3, caspase-1, and GSDMD were measured by quantitative real-time PCR, western blotting, immunofluorescence assay, and immunohistochemistry.

RESULTS

We demonstrated for the first time that the levels of NLRP3, caspase-1, GSDMD, IL-1β, and IL-18 were up-regulated in hyperphosphatemia-induced calcifying VSMCs. Blockade of caspase-1 activation by VX-765 inhibited pyroptosis-related molecules and VSMC calcification in a concentration-dependent manner in vitro. Further analysis of aortas from calcified CKD rats showed an up-regulation of caspase-1 and GSDMD expression compared with those non-calcified vascular tissue from control rats or with those decreased-calcified vascular tissue from CKD rats treated with 50 mg/kg/d, which indicated that pyroptotic indicators were tightly correlated with CKD arterial calcification. In vitro studies further demonstrated that VX-765 ameliorated hyperphosphatemia-induced VSMCs calcification through inhibiting the STAT3 activation.

CONCLUSIONS

Our findings indicated that VX-765 could inhibit hyperphosphatemia-induced calcifying VSMCs and ameliorate vascular calcification in CKD rats. VX-765 might be a potential treatment strategy for CKD vascular calcification.

Tongxinluo attenuates atherosclerosis by inhibiting ROS/NLRP3/caspase-1-mediated endothelial cell pyroptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Tongxinluo (TXL) is one of the most common traditional Chinese medicines and plays a vital role in treating atherosclerosis (AS). Endothelial cell (EC) pyroptosis plays a crucial role in the development of AS. Previous research revealed the inhibitory function of TXL in EC apoptosis and autophagy. However, whether TXL can inhibit the pyroptosis of ECs has not been determined.

AIM OF THE STUDY

To explore the influence of TXL on EC pyroptosis and determine its underlying mechanism of action in AS.

MATERIALS AND METHODS

The TXL components were determined by ultra-performance liquid chromatography coupled with a photodiode array detector. We used ApoE^-/- mice to establish a disease model of AS. After treatment with TXL, we recorded pathological changes in the mice and performed immunofluorescence staining of mice aortas. We also measured protein and gene levels to explore the influence of TXL on pyroptosis in vivo. The model was established by stimulating mouse aortic endothelial cells (MAECs) with oxidized low-density lipoprotein (ox-LDL) and analyzing the effect of TXL on pyroptosis by Western blotting (WB), real-time PCR (RT-PCR), and flow cytometry (FCM). We also investigated the impact of TXL on reactive oxygen species (ROS) by FCM and WB.

RESULTS

Ten major components of TXL were detected. The vivo results showed that TXL inhibited the development of AS and decreased EC pyroptosis, the activation of caspase-1, and the release of inflammatory cytokines. The vitro experiments showed that TXL significantly reduced the extent of injury to MAECs by oxidized LDL (ox-LDL). TXL reversed the high expression of gasdermin D and other proteins induced by ox-LDL and had a significant synergistic effect with the caspase-1 inhibitor VX-765. We also confirmed that TXL decreased the accumulation of ROS and the expression levels of its essential regulatory proteins Cox2 and iNOS. When ROS accumulation was reduced, EC pyroptotic damage was reduced accordingly.

CONCLUSION

Our results indicated that TXL inhibited EC pyroptosis in AS. Reducing the accumulation of ROS may be the essential mechanism of AS inhibition by TXL.

The emerging crosstalk between atherosclerosis-related microRNAs and Bermuda triangle of foam cells: Cholesterol influx, trafficking, and efflux

In atherosclerosis, the gradual buildup of lipid particles into the sub-endothelium of damaged arteries leads to numerous lipid alterations. The absorption of these modified lipids by monocyte-derived macrophages in the arterial wall leads to cholesterol accumulation and increases the likelihood of foam cell formation and fatty streak, which is an early characteristic of atherosclerosis. Foam cell formation is related to an imbalance in cholesterol influx, trafficking, and efflux. The formation of foam cells is heavily regulated by various mechanisms, among them, the role of epigenetic factors like microRNA alteration in the formation of foam cells has been well studied. Recent studies have focused on the potential interplay between microRNAs and foam cell formation in the pathogenesis of atherosclerosis; nevertheless, there is significant space to progress in this attractive field. This review has focused to examine the underlying processes of foam cell formation and microRNA crosstalk to provide a deep insight into therapeutic implications in atherosclerosis.

Inflammation and Heart Failure: Searching for the Enemy-Reaching the Entelechy

The pivotal role of inflammation in the pathophysiology of heart-failure (HF) development and progression has long been recognized. High blood levels of pro-inflammatory and inflammatory markers are present and associated with adverse outcomes in patients with HF. In addition, there seems to be an interrelation between inflammation and neurohormonal activation, the cornerstone of HF pathophysiology and management. However, clinical trials involving anti-inflammatory agents have shown inconclusive or even contradictory results in improving HF outcomes. In the present review, we try to shed some light on the reciprocal relationship between inflammation and HF in an attempt to identify the central regulating factors, such as inflammatory cells and soluble mediators and the related inflammatory pathways as potential therapeutic targets.

Interactions between PCSK9 and NLRP3 inflammasome signaling in atherosclerosis

Atherosclerosis is an early pathological basis of numerous cardiovascular events that result in death or disability. Recent studies have described PCSK9 as a novel target for the treatment of atherosclerosis; PCSK9 is capable of degrading LDLR on the surface of hepatocytes through the regulation of lipid metabolism, and it can function as a novel inflammatory modulator in atherosclerosis. Inflammasomes are important intracellular multiprotein complexes that promote the inflammatory response in atherosclerosis. Among inflammasomes, the NLRP3 inflammasome is particularly notable because of its important role in the development of atherosclerotic disease. After activation, NLRP3 forms a complex with ASC and pro-caspase-1, converting pro-caspase-1 into activated caspase-1, which may trigger the release of IL-1β and IL-18 and contribute to the inflammatory response. Several recent studies have indicated that there may be interactions between PCSK9 and the NLRP3 inflammasome, which may contribute to the inflammatory response that drives atherosclerosis development and progression. On the one hand, the NLRP3 inflammasome plays an important role via IL-1β in regulating PCSK9 secretion. On the other hand, PCSK9 regulates caspase-1-dependent pyroptosis by initiating mtDNA damage and activating NLRP3 inflammasome signaling. This paper reviews the mechanisms underlying PCSK9 and NLRP3 inflammasome activation in the context of atherosclerosis. Furthermore, we describe the current understanding of the specific molecular mechanism underlying the interactions between PCSK9 and NLRP3 inflammasome signaling as well as the drug repositioning events that influence vascular cells and exert beneficial antiatherosclerotic effects. This review may provide a new therapeutic direction for the effective prevention and treatment of atherosclerosis in the clinic.

The emerging role of pyroptosis-related inflammasome pathway in atherosclerosis

Atherosclerosis (AS), a chronic sterile inflammatory disorder, is one of the leading causes of mortality worldwide. The dysfunction and unnatural death of plaque cells, including vascular endothelial cells (VEC), macrophages, and vascular smooth muscle cells (VSMC), are crucial factors in the progression of AS. Pyroptosis was described as a form of cell death at least two decades ago. It is featured by plasma membrane swelling and rupture, cell lysis, and consequent robust release of cytosolic contents and pro-inflammatory mediators, including interleukin-1β (IL-1β), IL-18, and high mobility group box 1 (HMGB1). Pyroptosis of plaque cells is commonly observed in the initiation and development of AS, and the levels of pyroptosis-related proteins are positively correlated with plaque instability, indicating the crucial contribution of pyroptosis to atherogenesis. Furthermore, studies have also identified some candidate anti-atherogenic agents targeting plaque cell pyroptosis. Herein, we summarize the research progress in understating (1) the discovery and definition of pyroptosis; (2) the characterization and molecular mechanisms of pyroptosis; (3) the regulatory mechanisms of pyroptosis in VEC, macrophage, and VSMC, as well as their potential role in AS progression, aimed at providing therapeutic targets for the prevention and treatment of AS.

Molecular Characteristics of Cell Pyroptosis and Its Inhibitors: A Review of Activation, Regulation, and Inhibitors

Pyroptosis is an active and ordered form of programmed cell death. The signaling pathways of pyroptosis are mainly divided into canonical pathways mediated by caspase-1 and noncanonical pathways mediated by caspase-11. Cell pyroptosis is characterized by the activation of inflammatory caspases (mainly caspase-1, 4, 5, 11) and cleavage of various members of the Gasdermin family to form membrane perforation components, leading to cell membrane rupture, inflammatory mediators release, and cell death. Moderate pyroptosis is an innate immune response that fights against infection and plays an important role in the occurrence and development of the normal function of the immune system. However, excessive pyroptosis occurs and leads to immune disorders in many pathological conditions. Based on canonical pathways, research on pyroptosis regulation has demonstrated several pyroptotic inhibitors, including small-molecule drugs, natural products, and formulations of traditional Chinese medicines. In this paper, we review the characteristics and molecular mechanisms of pyroptosis, summarize inhibitors of pyroptosis, and propound that herbal medicines should be a focus on the research and development for pyroptosis blockers.

The Impact of Cytokines in Coronary Atherosclerotic Plaque: Current Therapeutic Approaches

Coronary atherosclerosis is a chronic pathological process that involves inflammation together with endothelial dysfunction and lipoprotein dysregulation. Experimental studies during the past decades have established the role of inflammatory cytokines in coronary artery disease, namely interleukins (ILs), tumor necrosis factor (TNF)-α, interferon-γ, and chemokines. Moreover, their value as biomarkers in disease development and progression further enhance the validity of this interaction. Recently, cytokine-targeted treatment approaches have emerged as potential tools in the management of atherosclerotic disease. IL-1β, based on the results of the CANTOS trial, remains the most validated option in reducing the residual cardiovascular risk. Along the same line, colchicine was also proven efficacious in preventing major adverse cardiovascular events in large clinical trials of patients with acute and chronic coronary syndrome. Other commercially available agents targeting IL-6 (tocilizumab), TNF-α (etanercept, adalimumab, infliximab), or IL-1 receptor antagonist (anakinra) have mostly been assessed in the setting of other inflammatory diseases and further testing in atherosclerosis is required. In the future, potential targeting of the NLRP3 inflammasome, anti-inflammatory IL-10, or atherogenic chemokines could represent appealing options, provided that patient safety is proven to be of no concern.

LncRNA MDRL Mitigates Atherosclerosis through miR-361/SQSTM1/NLRP3 Signaling

Objective

Long non-coding RNAs (lncRNAs) play many important roles in gene regulation and disease pathogenesis. Here, we sought to determine that mitochondrial dynamic related lncRNA (MDRL) modulates NLRP3 inflammasome activation and apoptosis of vascular smooth muscle cells (VSMCs) and protects arteries against atherosclerosis.

Methods

In vivo experiments, we applied LDLR knockout (LDLR^−/−) mice fed the high-fat diet to investigate the effects of MDRL on atherosclerosis. In vitro experiments, we applied mouse aortic smooth muscle cells to determine the mechanism of MDRL in abrogating NLRP3 inflammasome and inhibiting cell apoptosis through miR-361/sequentosome 1 (SQSTM1) by TUNEL staining, quantitative RT-PCR, western blot, microribonucleoprotein immunoprecipitation, and luciferase reporter assay.

Results

Downregulated MDRL and increased NLRP3 were observed in mouse atherosclerotic plaques, accompanied with the increase of miR-361. The results showed that MDRL overexpression significantly attenuated the burden of atherosclerotic plaque and facilitated plaque stability through inhibiting NLRP3 inflammasome activation and cell apoptosis, and vice versa. Mechanically, MDRL suppressed NLRP3 inflammasome activation and VSMC apoptosis via suppressing miR-361. Furthermore, miR-361 directly bound to the 3'UTR of SQSTM1 and inhibited its translation, subsequently activating NLRP3 inflammasome. Systematic delivery of miR-361 partly counteracted the beneficial effects of MDRL overexpression on atherosclerotic development in LDLR^−/− mice.

Conclusions

In summary, MDRL alleviates NLRP3 inflammasome activation and apoptosis in VSMCs through miR-361/SQSTM1/NLRP3 pathway during atherogenesis. These data indicate that MDRL and inhibition of miR-361 represent potential therapeutic targets in atherosclerosis-related diseases.

Novel role for caspase 1 inhibitor VX765 in suppressing NLRP3 inflammasome assembly and atherosclerosis via promoting mitophagy and efferocytosis

Atherosclerosis is a maladaptive chronic inflammatory disease, which remains the leading cause of death worldwide. The NLRP3 inflammasome constitutes a major driver of atherosclerosis, yet the mechanism of action is poorly understood. Mitochondrial dysfunction is essential for NLRP3 inflammasome activation. However, whether activated NLRP3 inflammasome exacerbates mitochondrial dysfunction remains to be further elucidated. Herein, we sought to address these issues applying VX765, a well-established inhibitor of caspase 1. VX765 robustly restrains caspase 1-mediated interleukin-1β production and gasdermin D processing. Our study assigned VX765 a novel role in antagonizing NLRP3 inflammasome assembly and activation. VX765 mitigates mitochondrial damage induced by activated NLRP3 inflammasome, as evidenced by decreased mitochondrial ROS production and cytosolic release of mitochondrial DNA. VX765 blunts caspase 1-dependent cleavage and promotes mitochondrial recruitment and phosphorylation of Parkin, a key mitophagy regulator. Functionally, VX765 facilitates mitophagy, efferocytosis and M2 polarization of macrophages. It also impedes foam cell formation, migration and pyroptosis of macrophages. VX765 boosts autophagy, promotes efferocytosis, and alleviates vascular inflammation and atherosclerosis in both ApoE^-/- and Ldlr^-/- mice. However, these effects of VX765 were abrogated upon ablation of Nlrp3 in ApoE^-/- mice. This work provides mechanistic insights into NLRP3 inflammasome assembly and this inflammasome in dictating atherosclerosis. This study highlights that manipulation of caspase 1 paves a new avenue to treatment of atherosclerotic cardiovascular disease.

Gasdermin D Deficiency Limits the Transition of Atherosclerotic Plaques to an Inflammatory Phenotype in ApoE Knock-Out Mice

Gasdermin D (GSDMD) is the key executor of pyroptotic cell death. Recent studies suggest that GSDMD-mediated pyroptosis is involved in atherosclerotic plaque destabilization. We report that cleaved GSDMD is expressed in macrophage- and smooth muscle cell-rich areas of human plaques. To determine the effects of GSDMD deficiency on atherogenesis, ApoE^−/− Gsdmd^−/− (n = 16) and ApoE^−/−Gsdmd^+/+ (n = 18) mice were fed a western-type diet for 16 weeks. Plaque initiation and formation of stable proximal aortic plaques were not altered. However, plaques in the brachiocephalic artery (representing more advanced lesions compared to aortic plaques) of ApoE^−/− Gsdmd^−/− mice were significantly smaller (115 ± 18 vs. 186 ± 16 × 10³ µm², p = 0.006) and showed features of increased stability, such as decreased necrotic core area (19 ± 4 vs. 37 ± 7 × 10³ µm², p = 0.03) and increased αSMA/MAC3 ratio (1.6 ± 0.3 vs. 0.7 ± 0.1, p = 0.01), which was also observed in proximal aortic plaques. Interestingly, a significant increase in TUNEL positive cells was observed in brachiocephalic artery plaques from ApoE^−/− Gsdmd^−/− mice (141 ± 25 vs. 62 ± 8 cells/mm², p = 0.005), indicating a switch to apoptosis. This switch from pyroptosis to apoptosis was also observed in vitro in Gsdmd^−/− macrophages. In conclusion, targeting GSDMD appears to be a promising approach for limiting the transition to an inflammatory, vulnerable plaque phenotype.

NF-κB/ABCA1 pathway aggravates ox-LDL-induced cell pyroptosis by activation of NLRP3 inflammasomes in THP-1-derived macrophages

OBJECTIVE

NF-κB (nuclear transcription factor-kappa B) plays a well-known function in the regulation of immune responses and inflammation, but growing evidences support a major role of it in atherosclerosis. Currently, the regulatory mechanism of NF-κB pathway involved in atherosclerosis remains unclear.

METHODS

To investigate the role of ox-LDL (oxidized low-density lipoprotein) in NF-κB regulation, the protein expression of phosphorylated NF-κB, a marker of NF-κB pathway activation was measured. The pyroptosis of macrophage was evaluated by western blot and fluorescence microscope. Cholesterol efflux capacity was determined by fluorescence assay and oil red O staining. The inhibitor of activation of NF-κB signal was used to assess the effect of NF-κB signal on macrophage pyroptosis and cholesterol efflux in macrophage. Small interfering RNA of ABCA1 (cholesterol transporters ATP binding boxes A1) was used to assess the effect of ABCA1 on macrophage pyroptosis.

RESULTS

In this study, we reported THP-1 derived macrophage can be stimulated to increase pyroptosis by ox-LDL in a concentration-dependent manner. Macrophage pyroptosis was correlated with enhanced activation of NF-κB signal. After using inhibitor of NF-κB phosphorylation to attenuate activation of NF-κB signal, we identified and confirmed the decrease of macrophage pyroptosis and the occurrence of ox-LDL-induced cholesterol efflux disorder. Furthermore, we found that the downregulation of ABCA1 led to increased cell inflammation death. But pyroptosis was blocked, may led to cholesterol efflux dysfunction.

CONCLUSION

Taken together, the present results indicate that the mechanism of NF-κB involved in the development of atherosclerosis depends on mediating cell pyroptosis and cholesterol efflux and provide significant light on macrophage NF-κB signal in atherosclerosis.

Pyroptosis: Role and Mechanisms in Cardiovascular Disease

Cardiovascular disease (CVD) is a common disease that poses a huge threat to human health. Irreversible cardiac damage due to cardiomyocyte death and lack of regenerative capacity under stressful conditions, ultimately leading to impaired cardiac function, is the leading cause of death worldwide. The regulation of cardiomyocyte death plays a crucial role in CVD. Previous studies have shown that the modes of cardiomyocyte death include apoptosis and necrosis. However, another new form of death, pyroptosis, plays an important role in CVD pathogenesis. Pyroptosis induces the amplification of inflammatory response, increases myocardial infarct size, and accelerates the occurrence of cardiovascular disease, and the control of cardiomyocyte pyroptosis holds great promise for the treatment of cardiovascular disease. In this paper, we summarized the characteristics, occurrence and regulation mechanism of pyroptosis are reviewed, and also discussed its role and mechanisms in CVD, such as atherosclerosis (AS), myocardial infarction (MI), arrhythmia and cardiac hypertrophy.

Inflammation and atherosclerosis: signaling pathways and therapeutic intervention

Atherosclerosis is a chronic inflammatory vascular disease driven by traditional and nontraditional risk factors. Genome-wide association combined with clonal lineage tracing and clinical trials have demonstrated that innate and adaptive immune responses can promote or quell atherosclerosis. Several signaling pathways, that are associated with the inflammatory response, have been implicated within atherosclerosis such as NLRP3 inflammasome, toll-like receptors, proprotein convertase subtilisin/kexin type 9, Notch and Wnt signaling pathways, which are of importance for atherosclerosis development and regression. Targeting inflammatory pathways, especially the NLRP3 inflammasome pathway and its regulated inflammatory cytokine interleukin-1β, could represent an attractive new route for the treatment of atherosclerotic diseases. Herein, we summarize the knowledge on cellular participants and key inflammatory signaling pathways in atherosclerosis, and discuss the preclinical studies targeting these key pathways for atherosclerosis, the clinical trials that are going to target some of these processes, and the effects of quelling inflammation and atherosclerosis in the clinic.

Recent advance in treatment of atherosclerosis: Key targets and plaque-positioned delivery strategies

Atherosclerosis, a chronic inflammatory disease of vascular wall, is a progressive pathophysiological process with lipids oxidation/depositing initiation and innate/adaptive immune responses. The coordination of multi systems covering oxidative stress, dysfunctional endothelium, diseased lipid uptake, cell apoptosis, thrombotic and pro-inflammatory responding as well as switched SMCs contributes to plaque growth. In this circumstance, inevitably, targeting these processes is considered to be effective for treating atherosclerosis. Arriving, retention and working of payload candidates mediated by targets in lesion direct ultimate therapeutic outcomes. Accumulating a series of scientific studies and clinical practice in the past decades, lesion homing delivery strategies including stent/balloon/nanoparticle-based transportation worked as the potent promotor to ensure a therapeutic effect. The objective of this review is to achieve a very brief summary about the effective therapeutic methods cooperating specifical targets and positioning-delivery strategies in atherosclerosis for better outcomes.

Pyroptosis-Induced Inflammation and Tissue Damage

Programmed cell deaths are pathways involving cells playing an active role in their own destruction. Depending on the signaling system of the process, programmed cell death can be divided into two categories, pro-inflammatory and non-inflammatory. Pyroptosis is a pro-inflammatory form of programmed cell death. Upon cell death, a plethora of cytokines are released and trigger a cascade of responses from the neighboring cells. The pyroptosis process is a double-edged sword, could be both beneficial and detrimental in various inflammatory disorders and disease conditions. A physiological outcome of these responses is tissue damage, and sometimes death of the host. In this review, we focus on the inflammatory response triggered by pyroptosis, and resulting tissue damage in selected organs.

Zhilong Huoxue Tongyu Capsule Alleviated the Pyroptosis of Vascular Endothelial Cells Induced by ox-LDL through miR-30b-5p/NLRP3

Background

Our previous studies have demonstrated a protective role of Zhilong Huoxue Tongyu capsule in atherosclerosis (AS); however, the molecular mechanisms are unclear.

Methods

Human coronary artery endothelial cells (HCAECs) were induced with oxidized low-density lipoprotein (ox-LDL) to obtain cellular AS models. Then, the medicated serum of Zhilong Huoxue Tongyu capsule was obtained and used for treatment with ox-LDL-induced HCAECs. The cell viability was detected by CCK-8 assay. Besides, the binding between miR-30b-5p and NLRP3 was determined by the dual-luciferase reporter gene system assay. Furthermore, ox-LDL-induced HCAECs were transfected with miR-30b-5p mimic or miR-30b-5p inhibitor. The pyroptosis of HCAECs was assessed by flow cytometry, LDH content detection, and qRT-PCR assays.

Results

10% medicated serum of Zhilong Huoxue Tongyu capsule was the maximum nontoxic concentration and it was used in subsequent assays. The rate of pyroptosis, LDH content, and the mRNA expression level of pyroptosis-related genes including NLRP3, ASC, Caspase 1, IL-1β, and IL-18 were prominently enhanced after HCAECs were induced by ox-LDL, which were markedly rescued with medicated serum of Zhilong Huoxue Tongyu capsule. In addition, the medicated serum of Zhilong Huoxue Tongyu capsule significantly enhanced the ox-LDL-induced reduction of miR-30b-5p level. NLRP3 could bind to miR-30b-5p and was negatively corrected with miR-30b-5p. Moreover, all the rates of pyroptosis, LDH content, and the mRNA expression levels of pyroptosis-related genes including NLRP3, ASC, Caspase 1, IL-1β, and IL-18 were further observably decreased after ox-LDL-induced HCAECs treated with medicated serum were transfected with miR-30b-5p mimic, while these were significantly rescued with transfection of miR-30b-5p inhibitor.

Conclusion

Zhilong Huoxue Tongyu capsule alleviated the pyroptosis of vascular endothelial cells induced by ox-LDL through miR-30b-5p/NLRP3.

Autophagy, Pyroptosis, and Ferroptosis: New Regulatory Mechanisms for Atherosclerosis

Atherosclerosis is a chronic inflammatory disorder characterized by the gradual buildup of plaques within the vessel wall of middle-sized and large arteries. The occurrence and development of atherosclerosis and the rupture of plaques are related to the injury of vascular cells, including endothelial cells, smooth muscle cells, and macrophages. Autophagy is a subcellular process that plays an important role in the degradation of proteins and damaged organelles, and the autophagy disorder of vascular cells is closely related to atherosclerosis. Pyroptosis is a proinflammatory form of regulated cell death, while ferroptosis is a form of regulated nonapoptotic cell death involving overwhelming iron-dependent lipid peroxidation. Both of them exhibit distinct features from apoptosis, necrosis, and autophagy in morphology, biochemistry, and genetics. However, a growing body of evidence suggests that pyroptosis and ferroptosis interact with autophagy and participate in the development of cancers, degenerative brain diseases and cardiovascular diseases. This review updated the current understanding of autophagy, pyroptosis, and ferroptosis, finding potential links and their effects on atherogenesis and plaque stability, thus providing ways to develop new pharmacological strategies to address atherosclerosis and stabilize vulnerable, ruptured plaques.

Therapeutic strategies targeting inflammation and immunity in atherosclerosis: how to proceed?

Atherosclerosis is a chronic inflammatory disease of the arterial wall, characterized by the formation of plaques containing lipid, connective tissue and immune cells in the intima of large and medium-sized arteries. Over the past three decades, a substantial reduction in cardiovascular mortality has been achieved largely through LDL-cholesterol-lowering regimes and therapies targeting other traditional risk factors for cardiovascular disease, such as hypertension, smoking, diabetes mellitus and obesity. However, the overall benefits of targeting these risk factors have stagnated, and a huge global burden of cardiovascular disease remains. The indispensable role of immunological components in the establishment and chronicity of atherosclerosis has come to the forefront as a clinical target, with proof-of-principle studies demonstrating the benefit and challenges of targeting inflammation and the immune system in cardiovascular disease. In this Review, we provide an overview of the role of the immune system in atherosclerosis by discussing findings from preclinical research and clinical trials. We also identify important challenges that need to be addressed to advance the field and for successful clinical translation, including patient selection, identification of responders and non-responders to immunotherapies, implementation of patient immunophenotyping and potential surrogate end points for vascular inflammation. Finally, we provide strategic guidance for the translation of novel targets of immunotherapy into improvements in patient outcomes.

In this Review, the authors provide an overview of the immune cells involved in atherosclerosis, discuss preclinical research and published and ongoing clinical trials assessing the therapeutic potential of targeting the immune system in atherosclerosis, highlight emerging therapeutic targets from preclinical studies and identify challenges for successful clinical translation.

Inflammation is an important component of the pathophysiology of cardiovascular disease; an imbalance between pro-inflammatory and anti-inflammatory processes drives chronic inflammation and the formation of atherosclerotic plaques in the vessel wall.

Clinical trials assessing canakinumab and colchicine therapies in atherosclerotic cardiovascular disease have provided proof-of-principle of the benefits associated with therapeutic targeting of the immune system in atherosclerosis.

The immunosuppressive adverse effects associated with the systemic use of anti-inflammatory drugs can be minimized through targeted delivery of anti-inflammatory drugs to the atherosclerotic plaque, defining the window of opportunity for treatment and identifying more specific targets for cardiovascular inflammation.

Implementing immunophenotyping in clinical trials in patients with atherosclerotic cardiovascular disease will allow the identification of immune signatures and the selection of patients with the highest probability of deriving benefit from a specific therapy.

Clinical stratification via novel risk factors and discovery of new surrogate markers of vascular inflammation are crucial for identifying new immunotherapeutic targets and their successful translation into the clinic.

Spotlight on NLRP3 Inflammasome: Role in Pathogenesis and Therapies of Atherosclerosis

Inflammation is an intricate biological response of body tissues to detrimental stimuli. Cardiovascular disease (CVD) is the leading cause of death worldwide, and inflammation is well documented to play a role in the development of CVD, especially atherosclerosis (AS). Emerging evidence suggests that activation of the NOD-like receptor (NLR) family and the pyridine-containing domain 3 (NLRP3) inflammasome is instrumental in inflammation and may result in AS. The NLRP3 inflammasome acts as a molecular platform that triggers the activation of caspase-1 and the cleavage of pro-interleukin (IL)-1β, pro-IL-18, and gasdermin D (GSDMD). The cleaved GSDMD forms pores in the cell membrane and initiates pyroptosis, inducing cell death and the discharge of intracellular pro-inflammatory factors. Hence, the NLRP3 inflammasome is a promising target for anti-inflammatory therapy against AS. In this review, we systematically summarized the current understanding of the activation mechanism of NLRP3 inflammasome, and the pathological changes in AS involving NLRP3. We also discussed potential therapeutic strategies targeting NLRP3 inflammasome to combat AS.

Targeting the Inflammasome in Cardiovascular Disease

The pathogenesis of cardiovascular disease (CVD) is complex and multifactorial, and inflammation plays a central role. Inflammasomes are multimeric protein complexes that are activated in a 2-step manner in response to infection or tissue damage. Upon activation the proinflammatory cytokines, interleukins-1β and -18 are released. In the last decade, the evidence that inflammasome activation plays an important role in CVD development became stronger. We discuss the role of different inflammasomes in the pathogenesis of CVD, focusing on atherosclerosis and heart failure. This review also provides an overview of existing experimental studies and clinical trials on inflammasome inhibition as a therapeutic target in these disorders.

Programmed Cell Death: Complex Regulatory Networks in Cardiovascular Disease

Abnormalities in programmed cell death (PCD) signaling cascades can be observed in the development and progression of various cardiovascular diseases, such as apoptosis, necrosis, pyroptosis, ferroptosis, and cell death associated with autophagy. Aberrant activation of PCD pathways is a common feature leading to excessive cardiac remodeling and heart failure, involved in the pathogenesis of various cardiovascular diseases. Conversely, timely activation of PCD remodels cardiac structure and function after injury in a spatially or temporally restricted manner and corrects cardiac development similarly. As many cardiovascular diseases exhibit abnormalities in PCD pathways, drugs that can inhibit or modulate PCD may be critical in future therapeutic strategies. In this review, we briefly describe the process of various types of PCD and their roles in the occurrence and development of cardiovascular diseases. We also discuss the interplay between different cell death signaling cascades and summarize pharmaceutical agents targeting key players in cell death signaling pathways that have progressed to clinical trials. Ultimately a better understanding of PCD involved in cardiovascular diseases may lead to new avenues for therapy.

C1q tumor necrosis factor-related protein 1: a promising therapeutic target for atherosclerosis

ABSTRACT

Atherosclerosis serves as the pathological basis of most cardiovascular and cerebrovascular diseases. C1q tumor necrosis factor-related protein (CTRP1) is a 35-kDa glycoprotein synthesized by various tissues and cells, such as adipose tissue and macrophages. As an adiponectin paralog, CTRP1 signals through adiponectin receptor 1 (AdipoR1) and participates in a variety of pathophysiological processes. Circulating CTRP1 levels are significantly increased in patients with coronary artery disease. Importantly, CTRP1 was shown to accelerate the development of atherosclerosis by promoting vascular inflammation, macrophage foam cell formation and endothelial barrier dysfunction. This review focused on recent advances regarding the role of CTRP1 in atherogenesis with an emphasis on its potential as a novel biomarker and a promising therapeutic target for atherosclerosis-related diseases.

The protective effect of quercetin on macrophage pyroptosis via TLR2/Myd88/NF-κB and ROS/AMPK pathway

AIMS

Pyroptosis is a pro-inflammatory form of programmed cell death, which plays a vital role in the development of inflammatory diseases. As a natural flavonoid, quercetin has been shown to possess anti-inflammatory activity, but its effects on macrophage pyroptosis is still unclear. Therefore, this study aims to investigate the effects of quercetin on macrophage pyroptosis and the underlying mechanism.

MATERIAL AND METHODS

LPS/ATP treatment was used to induce THP-1 macrophage pyroptosis. Cell counting kit-8 (CCK-8) assay was used to evaluate cell viability. Scanning electron microscope (SEM) was used to detect cell morphology. Hoechst/propidium iodide (PI) staining and lactate dehydrogenase (LDH) assay were performed to evaluate the cell membrane integrity. The expression of key components and effectors of nod-like receptors3 (NLRP3) inflammasome were examined by real-time PCR and western blot. Immunofluorescence staining was used to detect reactive oxygen species (ROS) level and P65 nuclear translocation.

KEY FINDINGS

Our results showed that quercetin prevented THP-1 macrophage pyroptosis by reducing the expression of NLRP3 and cleaved-caspase1, as well as IL-1β and N-GSDMD in a concentration dependent manner. Quercetin suppressed NLRP3 inflammasome activation by inhibiting ROS overproduction. Moreover, quercetin inhibited the phosphorylation of P65 and its translocation from cytoplasm into nuclear. In addition, we found that quercetin suppressed the increase of TLR2/Myd88 and p-AMPK induced by LPS/ATP, while both TLR2 and AMPK agonist weakened the inhibitory effect of quercetin on the activity of NLRP3 inflammasome and alleviated the protective effect on macrophages pyroptosis.

SIGNIFICANCE

Quercetin possesses a protective effect on macrophages pyroptosis via TLR2/Myd88/NF-κB and ROS/AMPK pathway.

Pyroptosis: A promising therapeutic target for noninfectious diseases

Pyroptosis, which is characterized by gasdermin family protein-mediated pore formation, cellular lysis and the release of pro-inflammatory cytokines, is a form of programmed cell death associated with intracellular pathogens-induced infection. However, emerging evidence indicates that pyroptosis also contributes to sterile inflammation. In this review, we will first illustrate the biological process of pyroptosis. Then, we will focus on the pathogenic effects of pyroptosis on multiple noninfectious disorders. At last, we will characterize several specific pyroptotic inhibitors targeting the pyroptotic signalling pathway. These data demonstrate that pyroptosis plays a prominent role in sterile diseases, thereby providing a promising approach to the treatment of noninfective inflammatory disorders.