Nicotine induces macrophage pyroptosis via LINC01272/miR-515/KLF6 axis

Epigenetic regulation of diverse regulated cell death modalities in cardiovascular disease: Insights into necroptosis, pyroptosis, ferroptosis, and cuproptosis

Cell death constitutes a critical component of the pathophysiology of cardiovascular diseases. A growing array of non-apoptotic forms of regulated cell death (RCD)-such as necroptosis, ferroptosis, pyroptosis, and cuproptosis-has been identified and is intimately linked to various cardiovascular conditions. These forms of RCD are governed by genetically programmed mechanisms within the cell, with epigenetic modifications being a common and crucial regulatory method. Such modifications include DNA methylation, RNA methylation, histone methylation, histone acetylation, and non-coding RNAs. This review recaps the roles of DNA methylation, RNA methylation, histone modifications, and non-coding RNAs in cardiovascular diseases, as well as the mechanisms by which epigenetic modifications regulate key proteins involved in cell death. Furthermore, we systematically catalog the existing epigenetic pharmacological agents targeting novel forms of RCD and their mechanisms of action in cardiovascular diseases. This article aims to underscore the pivotal role of epigenetic modifications in precisely regulating specific pathways of novel RCD in cardiovascular diseases, thus offering potential new therapeutic avenues that may prove more effective and safer than traditional treatments.

Pyroptosis in health and disease: mechanisms, regulation and clinical perspective

Pyroptosis is a type of programmed cell death characterized by cell swelling and osmotic lysis, resulting in cytomembrane rupture and release of immunostimulatory components, which play a role in several pathological processes. Significant cellular responses to various stimuli involve the formation of inflammasomes, maturation of inflammatory caspases, and caspase-mediated cleavage of gasdermin. The function of pyroptosis in disease is complex but not a simple angelic or demonic role. While inflammatory diseases such as sepsis are associated with uncontrollable pyroptosis, the potent immune response induced by pyroptosis can be exploited as a therapeutic target for anti-tumor therapy. Thus, a comprehensive review of the role of pyroptosis in disease is crucial for further research and clinical translation from bench to bedside. In this review, we summarize the recent advancements in understanding the role of pyroptosis in disease, covering the related development history, molecular mechanisms including canonical, non-canonical, caspase 3/8, and granzyme-mediated pathways, and its regulatory function in health and multiple diseases. Moreover, this review also provides updates on promising therapeutic strategies by applying novel small molecule inhibitors and traditional medicines to regulate pyroptosis. The present dilemmas and future directions in the landscape of pyroptosis are also discussed from a clinical perspective, providing clues for scientists to develop novel drugs targeting pyroptosis.

Exploring the relationship between pyroptosis and inflammatory bone loss: Evidence from a cigarette smoke-induced osteoporosis mouse model

Smoking is by far one of the greatest public health threats and is recognized as an important predisposing factor for osteoporosis. Exposure to cigarette smoke (CS) has been reported to be associated with inflammation-associated diseases through the induction of pyroptosis. Nevertheless, the correlation between pyroptosis and bone loss induced by CS remains uninvestigated. Here, a mouse model of mainstream smoke exposure-induced osteoporosis was established. μCT, biomechanical testing, and immunohistochemical staining of bone tissue were used to assess the deleterious effects of CS on bone metabolism. In vitro, the effects of cigarette smoke extracts (CSE) on mouse primary bone marrow-derived mesenchymal stem cells (BMSCs) were tested by cell viability assays, gene and protein expression assays, and alizarin red staining. The utilization of the pyroptosis inhibitor MCC950 served to confirm the critical role of BMSCs pyroptosis in CS-induced osteoporosis. Our results indicated that exposure to mainstream smoke led to a notable decrease in the quantity of osteoblasts and hindered the process of osteogenic differentiation in mice. Additionally, there was a significant increase in the expression of pyroptosis-related proteins in the bone marrow. The inhibitory effects of CSE on cell viability and osteogenic differentiation of BMSCs were found to be dose-dependent in vitro. However, the presence of the pyroptosis inhibitor MCC950 significantly improved the impaired osteogenic differentiation and bone mineralization caused by CSE. These results highlight the crucial involvement of BMSCs pyroptosis in the development of bone loss induced by CS. In summary, the findings of this study provide novel evidence that CS exerts a detrimental effect on the process of osteogenesis in BMSCs through the induction of pyroptosis, ultimately leading to bone loss. Inhibition of pyroptosis effectively attenuated the toxicological effects of CS on BMSCs, providing a new target for preventing inflammatory osteoporosis.

Pathological Intraplaque Hemorrhage as the Gold Standard to Assess the Efficacy of Ultrasound in Predicting Vulnerable Carotid Plaque Rupture

OBJECTIVE

To assess the clinical utility of ultrasound in predicting the risk of carotid vulnerable plaque rupture using pathological intraplaque hemorrhage as the gold standard.

METHODS

A total of 118 patients who underwent endarterectomy due to symptomatic carotid artery stenosis were enrolled. Conventional ultrasound assessed the plaque thickness, area stenosis rate, echo, and surface morphology. Neovascularization were assessed by contrast-enhanced ultrasound (CEUS) and tracing intraplaque nonenhanced areas. According to neovascularization grade (0-4), plaques were classified as low-, intermediate-, and high risk. Fresh intraplaque hemorrhage within the pathology was adopted as the gold standard for diagnosing plaque rupture risk. Thus, we divided patients into ruptured risk and nonruptured risk groups to assess the value of crucial factors for plaque rupture risk using ultrasound.

RESULTS

Of the 118 patients, hypertension accounted for 71.2%, hyperlipidemia 68.6%, diabetes 52.5%, and statin history 64.4%. In the rupture risk group, diabetes, smoking, and stenosis rate were significantly higher than the nonrupture risk group (P < .001); plaque thickness ≥4 mm (P > .05); and mainly hypoechoic with irregular surface morphology (P < .001), nonenhanced areas in the plaques (P < .001), and neovascularization >grade 2 (P < .001). Compared with the low-risk group, plaque rupture risk was 7.219 times higher in the medium-risk group and 18.333 times higher in the high-risk group. The kappa value of the interobserver consistency of crucial ultrasound parameters was >0.75, and the intraclass correlation coefficient was 0.919 (P < .01).

CONCLUSIONS

Both conventional ultrasound and CEUS have significant clinical importance in the prediction of rupture risk in vulnerable carotid plaques, thereby enabling stroke risk stratification and the assessment of plaque rupture risk.

Pyroptosis-related non-coding RNAs emerging players in atherosclerosis pathology

Globally, atherosclerosis a persistent inflammatory condition of the artery walls continues to be the primary cause of cardiovascular illness and death. The ncRNAs are important regulators of important signalling pathways that affect pyroptosis and the inflammatory environment in atherosclerotic plaques. Comprehending the complex interaction between pyroptosis and non-coding RNAs (ncRNAs) offers fresh perspectives on putative therapeutic targets for ameliorating cardiovascular problems linked to atherosclerosis. The discovery of particular non-coding RNA signatures linked to the advancement of atherosclerosis could lead to the creation of novel biomarkers for risk assessment and customised treatment approaches. A thorough investigation of the regulatory networks regulated by these non-coding RNAs has been made possible by the combination of cutting-edge molecular methods and bioinformatics tools. Studying pyroptosis-related ncRNAs in detail appears to be a promising way to advance our understanding of disease pathophysiology and develop focused therapeutic methods as we work to unravel the complex molecular tapestry of atherosclerosis. This review explores the emerging significance of non-coding RNAs (ncRNAs) in the regulation of pyroptosis and their consequential impact on atherosclerosis pathology.

ARID5B-mediated LINC01128 epigenetically activated pyroptosis and apoptosis by promoting the formation of the BTF3/STAT3 complex in β2GPI/anti-β2GPI-treated monocytes

BACKGROUND

Alterations of the trimethylation of histone 3 lysine 4 (H3K4me3) mark in monocytes are implicated in the development of autoimmune diseases. Therefore, the purpose of our study was to elucidate the role of H3K4me3-mediated epigenetics in the pathogenesis of antiphospholipid syndrome (APS).

METHODS

H3K4me3 Cleavage Under Targets and Tagmentation and Assay for Transposase-Accessible Chromatin were performed to determine the epigenetic profiles. Luciferase reporter assay, RNA immunoprecipitation, RNA pull-down, co-immunoprecipitation and chromatin immunoprecipitation were performed for mechanistic studies. Transmission electron microscopy and propidium iodide staining confirmed cell pyroptosis. Primary monocytes from patients with primary APS (PAPS) and healthy donors were utilised to test the levels of key molecules. A mouse model mimicked APS was constructed with beta2-glycoprotein I (β2GPI) injection. Blood velocity was detected using murine Doppler ultrasound.

RESULTS

H3K4me3 signal and open chromatin at the ARID5B promoter were increased in an in vitro model of APS. The epigenetic factor ARID5B directly activated LINC01128 transcription at its promoter. LINC01128 promoted the formation of the BTF3/STAT3 complex to enhance STAT3 phosphorylation. Activated STAT3 interacted with the NLRP3 promoter and subsequently stimulated pyroptosis and apoptosis. ARID5B or BTF3 depletion compensated for LINC01128-induced pyroptosis and apoptosis by inhibiting STAT3 phosphorylation. In mice with APS, β2GPI exposure elevated the levels of key proteins of pyroptosis and apoptosis pathways in bone marrow-derived monocytes, reduced the blood velocity of the ascending aorta, increased the thrombus size of the carotid artery, and promoted the release of interleukin (IL)-18, IL-1β and tissue factor. Patients with PAPS had the high-expressed ARID5B and LINC01128, especially those with triple positivity for antiphospholipid antibodies. Moreover, there was a positive correlation between ARID5B and LINC01128 expression.

CONCLUSION

This study indicated that ARID5B/LINC01128 was synergistically upregulated in APS, and they aggravated disease pathogenesis by enhancing the formation of the BTF3/STAT3 complex and boosting p-STAT3-mediated pyroptosis and apoptosis, thereby providing candidate therapeutic targets for APS.

HIGHLIGHTS

The H3K4me3 mark and chromatin accessibility at the ARID5B promoter are increased in vitro model mimicked APS. ARID5B-mediated LINC01128 induces pyroptosis and apoptosis via p-STAT3 by binding to BTF3. ARID5B is high- expressed in patients with primary APS and positively correlated with LINC01128 expression. OICR-9429 treatment mitigates pyroptosis and related inflammation in vivo and in vitro models mimicked APS.