Caspase-1 Abrogates the Salutary Effects of Hypertrophic Preconditioning in Pressure Overload Hearts via IL-1β and IL-18

Overview of pyroptosis mechanism and in-depth analysis of cardiomyocyte pyroptosis mediated by NF-κB pathway in heart failure

The pyroptosis of cardiomyocytes has become an essential topic in heart failure research. The abnormal accumulation of these biological factors, including angiotensin II, advanced glycation end products, and various growth factors (such as connective tissue growth factor, vascular endothelial growth factor, transforming growth factor beta, among others), activates the nuclear factor-κB (NF-κB) signaling pathway in cardiovascular diseases, ultimately leading to pyroptosis of cardiomyocytes. Therefore, exploring the underlying molecular biological mechanisms is essential for developing novel drugs and therapeutic strategies. However, our current understanding of the precise regulatory mechanism of this complex signaling pathway in cardiomyocyte pyroptosis is still limited. Given this, this study reviews the milestone discoveries in the field of pyroptosis research since 1986, analyzes in detail the similarities, differences, and interactions between pyroptosis and other cell death modes (such as apoptosis, necroptosis, autophagy, and ferroptosis), and explores the deep connection between pyroptosis and heart failure. At the same time, it depicts in detail the complete pathway of the activation, transmission, and eventual cardiomyocyte pyroptosis of the NF-κB signaling pathway in the process of heart failure. In addition, the study also systematically summarizes various therapeutic approaches that can inhibit NF-κB to reduce cardiomyocyte pyroptosis, including drugs, natural compounds, small molecule inhibitors, gene editing, and other cutting-edge technologies, aiming to provide solid scientific support and new research perspectives for the prevention and treatment of heart failure.

Regulated Cell Death Pathways in Pathological Cardiac Hypertrophy

Cardiac hypertrophy is characterized by an increased volume of individual cardiomyocytes rather than an increase in their number. Myocardial hypertrophy due to pathological stimuli encountered by the heart, which reduces pressure on the ventricular walls to maintain cardiac function, is known as pathological hypertrophy. This eventually progresses to heart failure. Certain varieties of regulated cell death (RCD) pathways, including apoptosis, pyroptosis, ferroptosis, necroptosis, and autophagy, are crucial in the development of pathological cardiac hypertrophy. This review summarizes the molecular mechanisms and signaling pathways underlying these RCD pathways, focusing on their mechanism of action findings for pathological cardiac hypertrophy. It intends to provide new ideas for developing therapeutic approaches targeted at the cellular level to prevent or reverse pathological cardiac hypertrophy.

Deletion of Interleukin-1β Converting Enzyme Alters Mouse Cardiac Structure and Function

Interleukin-1β converting enzyme (ICE, caspase-1) is a thiol protease that cleaves the pro-inflammatory cytokine precursors of IL-1β and IL-18 into active forms. Given the association between caspase-1 and cardiovascular pathology, we analyzed the hearts of ICE knockout (ICE KO) mice to test the hypothesis that caspase-1 plays a significant role in cardiac morphology and function. We characterized the histological and functional changes in the hearts of ICE KO mice compared to the Wild type. The cardiomyocytes from the neonatal ICE KO mice showed an impaired response to oxidative stress. Subsequently, the hearts from the ICE KO mice were hypertrophied, with a significant increase in the left ventricular and septal wall thickness and a greater LV mass/body weight ratio. The ICE KO mice hearts exhibited irregular myofibril arrangements and disruption of the cristae in the mitochondrial structure. Proapoptotic proteins that were significantly increased in the hearts of ICE KO versus the Wild type included pErk, pJNK, p53, Fas, Bax, and caspase 3. Further, the antiapoptotic proteins Bag-1 and Bcl-2 are activated in ICE KO hearts. Functionally, there was an increase in the left ventricular epicardial diameter and volume in ICE KO. In conclusion, our findings support the important role of caspase-1 in maintaining cardiac health; specifically, a significant decrease in caspase-1 is detrimental to the cardiovascular system.

Identification and validation of pyroptosis-related genes as potential biomarkers for hypertrophic cardiomyopathy: A comprehensive bioinformatics analysis

Pyroptosis plays a key role in the death of cells including cardiomyocytes, and it is associated with a variety of cardiovascular diseases. However, the role of pyroptosis-related genes (PRGs) in hypertrophic cardiomyopathy (HCM) is not well characterized. This study aimed to identify key biomarkers and explore the molecular mechanisms underlying the functions of the PRGs in HCM. The differentially expressed genes were identified by GEO2R, and the differentially expressed pyroptosis-related genes (DEPRGs) of HCM were identified by combining with PRGs. Enrichment analysis was performed using the "clusterProfiler" package of the R software. Protein-protein interactions (PPI) network analysis was performed using the STRING database, and hub genes were screened using cytoHubba. TF-miRNA coregulatory networks and protein-chemical interactions were analyzed using NetworkAnalyst. RT-PCR/WB was used for expression validation of HCM diagnostic markers. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and Western Blot (WB) were used to measure and compare the expression of the identified genes in the cardiac hypertrophy model and the control group. A total of 20 DEPRGs were identified, which primarily showed enrichment for the positive regulation of cytokine production, regulation of response to biotic stimulus, tumor necrosis factor production, and other biological processes. These processes primarily involved pathways related to Renin-angiotensin system, Adipocytokine signaling pathway and NF-kappa B signaling pathway. Then, a PPI network was constructed, and 8 hub genes were identified. After verification analysis, the finally identified HCM-related diagnostic markers were upregulated gene protein tyrosine phosphatase non-receptor type 11 (PTPN11), downregulated genes interleukin-1 receptor-associated kinase 3 (IRAK3), and annexin A2 (ANXA2). Further GSEA analysis revealed these 3 biomarkers primarily related to cardiac muscle contraction, hypertrophic cardiomyopathy, fatty acid degradation and ECM - receptor interaction. Moreover, we also elucidated the interaction network of these biomarkers with the miRNA network and known compounds, respectively. RT-PCR/WB results indicated that PTPN11 expression was significantly increased, and IRAK3 and ANXA2 expressions were significantly decreased in HCM. This study identified PTPN11, IRAK3, and ANXA2 as pyroptosis-associated biomarkers of HCM, with the potential to reveal the development and pathogenesis of HCM and could be potential therapeutic targets.

TAK1 Activation by NLRP3 Deficiency Confers Cardioprotection Against Pressure Overload-Induced Cardiomyocyte Pyroptosis and Hypertrophy

A comprehensive view of the role of NLRP3/caspase-1/GSDMD-mediated pyroptosis in pressure overload cardiac hypertrophy is presented in this study. Furthermore, mitigation of NLRP3 deficiency-induced pyroptosis confers cardioprotection against pressure overload through activation of TAK1, whereas this salutary effect is abolished by inhibition of TAK1 activity, highlighting a previously unrecognized reciprocally regulatory role of NLRP3-TAK1 governing inflammation-induced cell death and hypertrophic growth. Translationally, this study advocates strategies based on inflammation-induced cell death might be exploited therapeutically in other inflammatory and mechanical overload disorders, such as myocardial infarction and mitral regurgitation.

GSDMD (Gasdermin D) Mediates Pathological Cardiac Hypertrophy and Generates a Feed-Forward Amplification Cascade via Mitochondria-STING (Stimulator of Interferon Genes) Axis

Background:

Cardiac hypertrophy is initially an adaptive response of cardiomyocytes to neurohumoral or hemodynamic stimuli. Evidence indicates that Ang II (angiotensin II) or pressure overload causes GSDMD (gasdermin D) activation in cardiomyocytes and myocardial tissues. However, the direct impact of GSDMD on cardiac hypertrophy and its underlying mechanisms are not fully understood.

Methods and Results:

In this study, we examined the aberrant activation of GSDMD in mouse and human hypertrophic myocardia, and the results showed that GSDMD deficiency reduced Ang II or pressure overload–induced cardiac hypertrophy, dysfunction, and associated cardiomyocyte pyroptosis in mice. Mechanistically, Ang II–mediated GSDMD cleavage caused mitochondrial dysfunction upstream of STING (stimulator of interferon genes) activation in vivo and in vitro. Activation of STING, in turn, potentiated GSDMD-mediated cardiac hypertrophy. Moreover, deficiency of both GSDMD and STING suppressed cardiac hypertrophy in cardiac-specific GSDMD-overexpressing mice.

Conclusions:

Based on these findings, we propose a mechanism by which GSDMD generates a self-amplifying, positive feed-forward loop with the mitochondria-STING axis. This finding points to the prospects of GSDMD as a key therapeutic target for hypertrophy-associated heart diseases.