Gasdermin pores permeabilize mitochondria to augment caspase-3 activation during apoptosis and inflammasome activation

SUMOylation regulates GSDMD stability and pyroptosis

Various post-translational modifications (PTMs), such as palmitoylation, acetylation, and ubiquitination, have been shown to regulate pyroptosis. However, the role of small ubiquitin-like modifier (SUMO) modification, known as SUMOylation, in regulating GSDMD activity and pyroptosis remains unclear. Here, we demonstrate that inhibition of SUMOylation reduces inflammatory pyroptosis by downregulating GSDMD expression. Identification of key SUMOylation sites on GSDMD-K177, is critical for regulates pyroptosis. Furthermore, we identify SENP3 as a critical deSUMOylating enzyme that binds to GSDMD, suppressing GSDMD SUMO modification, which destabilizes GSDMD and inhibits LDH secretion. These findings highlight the role of SUMOylation in GSDMD mediated-pyroptosis, suggesting SUMO inhibitors as potential therapies for inflammatory diseases.

Anti-pyroptosis biomimetic nanoplatform loading puerarin for myocardial infarction repair: From drug discovery to drug delivery

Pyroptosis is a critical pathological mechanism implicated in myocardial damage following myocardial infarction (MI), and the crosstalk between macrophages and pyroptotic cardiomyocytes presents a formidable challenge for anti-pyroptosis therapies of MI. However, as single-target pyroptosis inhibitors frequently fail to address this crosstalk, the efficacy of anti-pyroptosis treatment post-MI remains inadequate. Therefore, the exploration of more potent anti-pyroptosis approaches is imperative for improving outcomes in MI treatment, particularly in addressing the crosstalk between macrophages and pyroptotic cardiomyocytes. Here, in response to this crosstalk, we engineered an anti-pyroptosis biomimetic nanoplatform (NM@PDA@PU), employing polydopamine (PDA) nanoparticles enveloped with neutrophil membrane (NM) for targeted delivery of puerarin (PU). Notably, network pharmacology is deployed to discern the most efficacious anti-pyroptosis drug (puerarin) among the 7 primary active monomers of TCM formulations widely applied in clinical practice and reveal the effect of puerarin on the crosstalk. Additionally, targeted delivery of puerarin could disrupt the malignant crosstalk between macrophages and pyroptotic cardiomyocytes, and enhance the effect of anti-pyroptosis by not only directly inhibiting cardiomyocytes pyroptosis through NLRP3-CASP1-IL-1β/IL-18 signal pathway, but reshaping the inflammatory microenvironment by reprogramming macrophages to anti-inflammatory M2 subtype. Overall, NM@PDA@PU could enhance anti-pyroptosis effect by disrupting the crosstalk between M1 macrophages and pyroptotic cardiomyocytes to protect cardiomyocytes, ameliorate cardiac function and improve ventricular remodeling, which providing new insights for the efficient treatment of MI.

Glutamine transporter inhibitor enhances the sensitivity of NSCLC to trametinib through GSDME-dependent pyroptosis

Trametinib, an inhibitor of mitogen-activated extracellular signal-regulated kinases 1/2 (MEK1/2), is used to treat BRAFV600E/K melanoma and non-small-cell lung cancer (NSCLC). Mutant Kirsten rat sarcoma viral oncogene homolog (KRAS) promotes glutamine utilization, therefore, in the present study we investigated the anti-cancer effects of trametinib in combination with V-9302, a glutamine transporter inhibitor, in NSCLC with KRAS mutations. Trametinib in combination with V-9302 exhibited a potent synergistic antitumor effect, inducing cell cycle arrest and pyroptosis. Mechanistically, combination treatment triggered caspase-3 activation and gasdermin E (GSDME) cleavage, as well as elevated lactate dehydrogenase (LDH) and IL-1β levels. Meanwhile, combination treatment reduced cyclin D1 and p-Rb levels and increased p27 expression. Moreover, this combination increased forkhead box class O3a (FOXO3a) levels and decreased forkhead box M1 (FOXM1) expression by regulating the phosphorylation of ERK, Akt, AMPK, and c-Jun N-terminal kinase (JNK). Trametinib in combination with V-9302 increased reactive oxygen species (ROS) generation and reduced glutathione (GSH) synthesis and ATP levels. Furthermore, V-9302 in combination with trametinib inhibited the trametinib-induced autophagy, thereby enhancing pyroptosis in cancer cells. In vivo, the co-administration of trametinib and V-9302 remarkably inhibited tumor growth in a xenograft mouse model compared to each drug alone. Taken together, the combination of trametinib and V-9302 resulted in increased pyroptosis and cell cycle arrest compared to each single agent through regulation of the FOXO3a/FOXM1 axis and autophagy and significantly enhanced antitumor efficacy in vivo. Our results suggest a potential new therapeutic strategy for KRAS-mutant NSCLC using trametinib in combination with glutamine restriction.

Mitochondrial injury and complement dysregulation are drivers of pathological inflammation in viral myocarditis

Enteroviruses cause nearly 1 billion global infections annually and are associated with a diverse array of human illnesses. Among these, myocarditis and the resulting chronic inflammation have been recognized as major contributing factors to virus-induced heart failure. Despite our growing understanding, very limited therapeutic strategies have been developed to address the pathological consequences of virus-induced chronic innate immune activation. Coxsackievirus B3 (CVB3) was used as a model cardiotropic enterovirus. We leveraged in vitro cell-based studies to investigate cardiomyocyte and macrophage interaction during CVB3 infection, as well as animal studies and unique human cardio specimens to evaluate mechanisms of viral heart injury. We present evidence that viral myocarditis is in part exacerbated by pathological activation of the complement pathway in cells, mice, and human cardiac tissues. We demonstrate unique cell type-specific responses to viral infection that are exacerbated by mitochondrial injury in cardiomyocytes and NFκB-dependent pro-inflammatory response in macrophages. Macrophages are robustly activated by damage-associated mitochondrial components, including mitochondrial proteins and lipid extracts. Mechanistically, we identify complement protective factors CD59/protectin and CD55/DAF as novel targets of viral proteinase that acts to release the brakes on complement-mediated autoinjury. Collectively, our study highlights a novel mechanism that can act as a potential contributor to CVB3 pathogenesis through mitochondrial injury-mediated autoimmunity.

IMPORTANCE

This study sheds light on how enteroviruses, specifically coxsackievirus B3, may contribute to heart failure by triggering harmful immune responses in the heart. We discovered that viral infections in heart cells cause mitochondrial damage, which in turn activates a destructive immune response involving the complement system. This immune activation is one of the significant contributors that lead to further injury of heart tissues, worsening the damage caused by the virus. Additionally, we identified key protective molecules that are targeted and disrupted by the virus, allowing the immune system to attack the heart even more aggressively. Understanding these mechanisms may provide additional insights into how viral infections can lead to chronic heart conditions and suggests potential therapeutic targets to prevent or reduce heart damage in patients affected by viral myocarditis.

Caspases in PANoptosis

Recent studies prove that the three well-established cell death pathways-pyroptosis, apoptosis, and necroptosis-are not isolated but rather engage in extensive crosstalk. PANoptosis, a newly identified pathway of inflammatory regulated cell death (RCD), integrates characteristics of apoptosis, pyroptosis, and necroptosis. Caspases are a family of conserved cysteine proteases that play critical roles in pyroptosis, apoptosis, and necroptosis. Similarly, caspases also play a role in PANoptosis. In this paper, we review the molecular mechanisms of these three RCDs and the crosstalk between them. We also delineate the discovery of PANoptosis and its association with disease. Furthermore, we discuss the caspase function in PANoptosis, mainly focusing on caspase-6 and caspase-8 molecules. This review describes the key molecules, especially caspases, in the context of PANoptosis research, aiming to provide a foundation for targeted interventions in PANoptosis-associated diseases.

Dapagliflozin attenuates skeletal muscle atrophy in diabetic nephropathy mice through suppressing Gasdermin D-mediated pyroptosis

BACKGROUND

Skeletal muscle atrophy is a clinical concern in diabetic nephropathy, and without effective therapeutic approaches. Massive evidence has demonstrated that dapagliflozin, a sodium-glucose co-transporter 2 inhibitor can relieve diabetic nephropathy by inhibiting glucose re-absorption or podocyte pyroptosis. Nevertheless, whether dapagliflozin could treat skeletal muscle atrophy or the potential protection mechanism in diabetic nephropathy mice is unclear.

METHODS

The variety of approaches were used to assess the particular histology-associated characteristics, mRNA, and protein expression. These included examing the morphology of renal and skeletal muscle tissues through H&E staining, detecting mRNA and protein expression through real-time PCR and Western blot analysis, and monitoring fasting blood glucose levels by using Blood Glucose Monitor Test Kits.

RESULTS

Dapagliflozin mitigated renal tissue injury with podocyte protein-nephrin and skeletal muscle atrophy effectively with mitochondrial-related proteins. Meanwhile, our research revealed that Casp3 was the target gene and dapagliflozin could decrease the expressions. Subsequently, we verified that dapagliflozin can effectively decrease canonical pyroptosis pathway proteins, which include Gasdermin D, NLRP3, Casp1, and ASC. Meanwhile, Palmitic acid (PA) induced Gasdermin E-N fragment (non-canonical pyroptosis protein) in C2C12 cells, and then released the inflammatory molecules such as IL-1β, IL-18, and NF-kappaB, which were suppressed by dapagliflozin treatment. Aside from that, dapagliflozin demonstrated a good binding affinity to the Casp3 and Gasdermin D protein, whereas it had a less binding affinity with NLRP3, Casp1, ASC, and Gasdermin E. At last, the Gasdermin D inhibitor can reverse the therapeutic effect of dapagliflozin.

CONCLUSION

Dapagliflozin alleviates skeletal muscle atrophy in diabetic nephropathy mice, which is through the Gasdermin D-mediated canonical pyroptosis pathway.

Ferroptosis and PANoptosis under hypoxia pivoting on the crosstalk between DHODH and GPX4 in corneal epithelium

Cell death under stress conditions like hypoxia, involves multiple interconnected pathways. In this study, a stable dihydroorotate dehydrogenase (DHODH) knockdown human corneal epithelial cell line was established to explore the regulation of hypoxic cell death, which was mitigated by various cell death inhibitors, particularly by a lipid peroxyl radical scavenger liproxstatin-1 (Lip-1), suggesting that hypoxic cell death involves crosstalk of ferroptosis and PANoptosis. We discovered that both DHODH and Glutathione peroxidase 4 (GPX4) protected cells from hypoxic death by inhibiting lipid peroxidation, mitochondrial reactive oxygen species (ROS) and maintaining mitochondrial membrane potential. However, upregulation of DHODH suppressed GPX4 upstream, exhibiting a trade-off in the expression levels between DHODH and GPX4 under hypoxia, with DHODH exerting a more decisive impact on cell survival. DHODH knockdown under hypoxia did not significantly alter lipid peroxidation levels, demonstrating the balance between DHODH and GPX4 expression finely regulated cellular ferroptosis homeostasis. This study highlights the complex interplay between ferroptosis and PANoptosis in hypoxic cell death, particularly the dual role of DHODH in regulating both pathways. DHODH is not merely maintaining the quantity of mitochondria but is promoting the selection of mitochondria favorable to cell survival. These findings not only deepen our understanding of cell death but also suggest potential therapeutic strategies for diseases involving oxidative stress and mitochondrial dysfunction.

Exploring the Role of Macrophages and Their Associated Structures in Rheumatoid Arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, invasive autoimmune disease characterized by symmetrical polyarthritis involving synovial inflammation. Epidemiological studies indicate that the incidence of RA continues to rise, yet the pathogenesis of this disease remains not fully understood. A significant infiltration of macrophages is observed in the synovium of RA patients. It can be inferred that macrophages likely play a crucial role in the onset and progression of RA.

SUMMARY

This review aims to summarize the research progress on the mechanisms by which macrophages and their associated structures contribute to RA, as well as potential therapeutic approaches, aiming to provide new insights into the study of RA pathogenesis and its clinical treatment.

KEY MESSAGES

During the course of RA, besides the inherent roles of macrophages, these cells respond to microenvironmental changes such as pathogen invasion or tissue damage by undergoing polarization, pyroptosis, or forming macrophage extracellular traps (METs), all of which influence inflammatory responses and immune homeostasis, thereby mediating the occurrence and development of RA. Additionally, macrophages secrete exosomes, which participate in intercellular communication and signal transduction processes, thus contributing to the progression of RA. Therefore, it is critical to elucidate how macrophages and their related structures function in RA.

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, invasive autoimmune disease characterized by symmetrical polyarthritis involving synovial inflammation. Epidemiological studies indicate that the incidence of RA continues to rise, yet the pathogenesis of this disease remains not fully understood. A significant infiltration of macrophages is observed in the synovium of RA patients. It can be inferred that macrophages likely play a crucial role in the onset and progression of RA.

SUMMARY

This review aims to summarize the research progress on the mechanisms by which macrophages and their associated structures contribute to RA, as well as potential therapeutic approaches, aiming to provide new insights into the study of RA pathogenesis and its clinical treatment.

KEY MESSAGES

During the course of RA, besides the inherent roles of macrophages, these cells respond to microenvironmental changes such as pathogen invasion or tissue damage by undergoing polarization, pyroptosis, or forming macrophage extracellular traps (METs), all of which influence inflammatory responses and immune homeostasis, thereby mediating the occurrence and development of RA. Additionally, macrophages secrete exosomes, which participate in intercellular communication and signal transduction processes, thus contributing to the progression of RA. Therefore, it is critical to elucidate how macrophages and their related structures function in RA.

GSDM family and glioma

Biomarkers play a central role in diagnosing, prognosis, and therapeutic management of gliomas, a diverse group of malignancies arising from glial cells in the brain and spinal cord. Among the various emerging biomarkers, the gasdermin protein family has attracted attention for its involvement in pyroptosis. Understanding the expression and function of GSDM in gliomas may provide new insights into tumor behavior and new avenues for therapeutic intervention. This review discusses the GSDM family's significance as a glioma biomarker, explores its dual role in tumor suppression, and highlights its potential utility in clinical practice as a novel target for glioma therapy.

An "Outer Piezoelectric and Inner Epigenetic" Logic-Gated PANoptosis for Osteosarcoma Sono-Immunotherapy and Bone Regeneration

The precise manipulation of PANoptosis, a newly defined cell death pathway encompassing pyroptosis, apoptosis, and necroptosis, is highly desired to achieve safer cancer immunotherapy with tumor-specific inflammatory responses and minimal side effects. Nonetheless, this objective remains a formidable challenge. Herein, an "AND" logic-gated strategy for accurately localized PANoptosis activation, utilizing composite 3D-printed bioactive glasses scaffolds integrated with epigenetic regulator-loaded porous piezoelectric SrTiO3 nanoparticles is proposed. The "logic-gated" strategy is co-programmed by an "outer" input signal of exogenous ultrasound irradiation to produce reactive oxygen species and an "inner" input signal of acid tumor microenvironment to ensure the epigenetic demethylation regulation, guaranteeing the tumor-specific PANoptosis. Specifically, immunogenic PANoptosis triggers dendritic cell maturation and cytotoxic T cell activation, amplifying antitumor immune responses and significantly suppressing osteosarcoma growth, with a suppression rate of ≈73.47 ± 5.2%. In addition, the well-known bioactivities of Sr-doped scaffolds expedite osteogenic differentiation and reinforce bone regeneration. Therefore, this work provides a paradigm of logic-gated sono-piezoelectric biomaterial platform with concurrently exogenous/endogenous activated PANoptosis for controlled sono-immunotherapy of osteosarcoma, and related bone defects repair.

Gambogic acid induces GSDME dependent pyroptotic signaling pathway via ROS/P53/Mitochondria/Caspase-3 in ovarian cancer cells

Gambogic acid (GA) is a naturally active compound extracted from the Garcinia hanburyi with various anticancer activities. However, whether GA induces pyroptosis (a newly discovered inflammation-mediated programmed cell death mechanism) in ovarian cancer (OC) has not yet been reported. This study revealed that GA treatment reduced cell viability by inducing pyroptosis in OC cell lines. Typical pyroptosis morphological manifestations such as cell swelling with large bubbles and loss of cell membrane integrity, were observed. Cleaved caspase-3 and GSDME-N levels increased after GA treatment, and knocking out GSDME or using a caspase-3 inhibitor could switch GA-induced cell death from pyroptosis to apoptosis, indicating GA induced caspase-3/GSDME-dependent pyroptosis. Furthermore, this research indicated that GA significantly increased reactive oxygen species (ROS) and p53 phosphorylation. OC cells pretreated with ROS inhibitor N-Acetylcysteine (NAC) and the specific p53 inhibitor pifithrin-μ could completely reverse the pyroptosis post-treatment. Elevated p53 and phosphorylated p53 reduced mitochondrial membrane potential (MMP) and Bcl-2, increase the expression of Bax, and damage mitochondria by releasing cytochrome c to activate the downstream pyroptosis pathway. Different doses of GA inhibited tumor growth in ID8 tumor-bearing mice, and high-dose GA increased in tumor-infiltrating lymphocytes CD3, CD4, and CD8 were detected in tumor tissues. Notably, the expressions of GSDME-N, cleaved caspase-3 and other proteins were increased in tumor tissues with high-dose GA groups. These findings demonstrate that GA-treated OC cells could induce GSDME-mediated pyroptosis through the ROS/p53/mitochondria signaling pathway and caspase-3/-9 activation. Thus, GA is a promising therapeutic agent for OC treatment.

Berberine shaping the tumor immune landscape via pyroptosis

Pyroptosis is a programmed cell death (PCD) mainly mediated by the Gasdermin family of proteins, among which Gasdermin E (GSDME) is considered a tumor suppressor gene. GSDME can recruit immune cells to the tumor microenvironment (TME) and promote their effects. Activating and enhancing adaptive immunity through GSDME is a potential solution for anti-tumor therapy. Here we reported that berberine (BBR), a small molecule from traditional Chinese medicine, as a GSDME activator, induced caspase-3 (C-3)/GSDME pathway-mediated pyroptosis through the mitochondrial pathway, improved the immunosuppressive state of the tumor microenvironment, and thus promoted anti-tumor immunity. We determined the induction of pyroptosis of 4 T1 cells by BBR through various experiments, and investigated the immune activation effect of BBR by co-culture in vitro, which induced DCs maturation and macrophage polarization. Zebrafish embryo toxicity experiments were used to evaluate the in vivo safety of berberine. Furthermore, the in vivo antitumor and immune activation effects of BBR were investigated using 4 T1 orthotopic model mice, and the results showed that BBR could eliminate orthotopic tumor cells by activating local and systemic immunity. Moreover, we observed that BBR significantly inhibited breast cancer lung metastasis. In summary, our results showd the role of BBR as a GSDME activator stimulated both local and systemic antitumor immune responses by inducing pyroptosis, effectively preventing tumor development and metastasis.

Caspase family in autoimmune diseases

Programmed cell death (PCD) plays a crucial role in maintaining tissue homeostasis, with its primary forms including apoptosis, pyroptosis, and necroptosis. The caspase family is central to these processes, and its complex functions across different cell death pathways and other non-cell death roles have been closely linked to the pathogenesis of autoimmune diseases. This article provides a comprehensive review of the role of the caspase family in autoimmune diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), type 1 diabetes (T1D), and multiple sclerosis (MS). It particularly emphasizes the intricate functions of caspases within various cell death pathways and their potential as therapeutic targets, thereby offering innovative insights and a thorough discussion in this field. In terms of therapy, strategies targeting caspases hold significant promise. We emphasize the importance of a holistic understanding of caspases in the overall concept of cell death, exploring their unique functions and interrelationships across multiple cell death pathways, including apoptosis, pyroptosis, necroptosis, and PANoptosis. This approach transcends the limitations of previous studies that focused on singular cell death pathways. Additionally, caspases play a key role in non-cell death functions, such as immune cell activation, cytokine processing, inflammation regulation, and tissue repair, thereby opening new avenues for the treatment of autoimmune diseases. Regulating caspase activity holds the potential to restore immune balance in autoimmune diseases. Potential therapeutic approaches include small molecule inhibitors (both reversible and irreversible), biological agents (such as monoclonal antibodies), and gene therapies. However, achieving specific modulation of caspases to avoid interference with normal physiological functions remains a major challenge. Future research must delve deeper into the regulatory mechanisms of caspases and their associated complexes linked to PANoptosis to facilitate precision medicine. In summary, this article offers a comprehensive and in-depth analysis, providing a novel perspective on the complex roles of caspases in autoimmune diseases, with the potential to catalyze breakthroughs in understanding disease mechanisms and developing therapeutic strategies.

Emerging role of PANoptosis in kidney diseases: molecular mechanisms and therapeutic opportunities

Kidney diseases represent a significant global public health challenge, characterized by complex pathogenesis, high incidence, low awareness, insufficient early screening, and substantial treatment disparities. Effective therapeutic options remain lacking. Programmed cell death (PCD), including apoptosis, pyroptosis, and necroptosis, play pivotal roles in the pathogenesis of various kidney diseases. In 2019, PANoptosis, a novel form of inflammatory cell death, was introduced, providing new insights into innate immunity and PCD research. Although research on PANoptosis in kidney diseases is still limited, identifying key molecules within PANoptosomes and understanding their regulatory roles is critical for disease prevention and management. This review summarizes the various forms of PCD implicated in kidney diseases, along with PANoptosomes activated by Z-DNA binding protein 1 (ZBP1), absent in melanoma 2 (AIM2), receptor-interacting protein kinase 1 (RIPK1), NOD-like receptor family CARD domain containing 12 (NLRP12), and NOD-like receptor family member C5 (NLRC5). It also reviews the advancements in PANoptosis research in the field of kidney diseases, particularly in renal tumors and acute kidney injuries (AKI). The goal is to establish a foundation for future research into the role of PANoptosis in kidney diseases.

Inflammasome Activation and Neutrophil Extracellular Traps in Atherosclerosis

The deposition of cholesterol containing cholesterol crystals and the infiltration of immune cells are features of atherosclerosis. Although the role of cholesterol crystals in the progression of atherosclerosis have long remained unclear, recent studies have clarified the involvement of cholesterol crystals in inflammatory responses. Cholesterol crystals activate the NLRP3 inflammasome, a molecular complex involved in the innate immune system. Activation of NLRP3 inflammasomes in macrophages cause pyroptosis, which is accompanied by the release of inflammatory cytokines such as IL-1β and IL-1α. Furthermore, NLRP3 inflammasome activation drives neutrophil infiltration into atherosclerotic plaques. Cholesterol crystals trigger NETosis against infiltrated neutrophils, a form of cell death characterized by the formation of neutrophil extracellular traps (NETs), which, in turn, prime macrophages to enhance inflammasome-mediated inflammatory responses. Colchicine, an anti-inflammatory drug effective in cardiovascular disease, is expected to inhibit cholesterol crystal-induced NLRP3 inflammasome activation and neutrophil infiltration. In this review, we illustrate the reinforcing cycle of inflammation that is amplified by inflammasome activation and NETosis.

Ferroptosis and pyroptosis are connected through autophagy: a new perspective of overcoming drug resistance

Drug resistance is a common challenge in clinical tumor treatment. A reduction in drug sensitivity of tumor cells is often accompanied by an increase in autophagy levels, leading to autophagy-related resistance. The effectiveness of combining chemotherapy drugs with autophagy inducers/inhibitors has been widely confirmed, but the mechanisms are still unclear. Ferroptosis and pyroptosis can be affected by various types of autophagy. Therefore, ferroptosis and pyroptosis have crosstalk via autophagy, potentially leading to a switch in cell death types under certain conditions. As two forms of inflammatory programmed cell death, ferroptosis and pyroptosis have different effects on inflammation, and the cGAS-STING signaling pathway is also involved. Therefore, it also plays an important role in the progression of some chronic inflammatory diseases. This review discusses the relationship between autophagy, ferroptosis and pyroptosis, and attempts to uncover the reasons behind the evasion of tumor cell death and the nature of drug resistance.

Osteosarcoma biomarker analysis and drug targeting prediction based on pyroptosis-related genes

Osteosarcoma is a malignant bone tumor originating from mesenchymal tissue. Recent studies have found that the tumor inflammatory microenvironment plays an important role in promoting the malignant characteristics and metastatic potential of malignant tumors. Pyroptosis, an inflammatory programmed cell death, elicits immune responses that exhibit anti-tumor effects through released factors and contents. Therefore, improving anti-tumor immunity by targeting osteosarcoma-related pyroptosis genes and pathways may be of great significance in delaying early metastasis of osteosarcoma and improving patient survival rate. The study aimed to identify pyroptosis-related genes and biomarkers in osteosarcoma, predicting therapeutic drugs targeting these genes. Gene expression profiles of osteosarcoma were retrieved from Gene Expression Omnibus and cross-referenced with GeneCards and Comparative Toxicogenomics Database to identify differentially expressed pyroptosis-related genes. We conducted enrichment analysis on intersecting genes to identify their biological processes and signaling pathways and assessed immune cell composition in the tumor microenvironment through immune infiltration analysis. In addition, we further utilized Cytoscape software to screen out the top 10 genes with Degree values among the intersected genes as hub genes and performed GSEA analysis and drug prediction based on the hub genes. A total of 22 differentially expressed pyroptosis-related genes were identified in osteosarcoma, with 10 of them (TP53, CYCS, IL-1A, IL-1B, IL-18, CASP-3, CASP-8, IL-6, TNF, CASP-1) pinpointed as hub genes. Enrichment analysis found that the 22 intersection genes are mainly associated with pyroptosis, apoptosis, immune regulation, and related biological processes. The results of data validation targeting hub genes suggest that IL-18, CASP-1, and CASP-8 may be key genes involved in the regulation of pyroptosis in osteosarcoma. Immune infiltration analysis shows statistical differences in the distribution of immune cells like naive B cells, monocytes, M2 macrophages, and dendritic/mast cells, suggesting they play a role in the osteosarcoma tumor microenvironment. Hub gene drug targets suggest Triethyl phosphate, Plinabulin, and Siltuximab as potential osteosarcoma treatments. Our findings suggest potential mechanisms of action for 22 pyroptosis-related genes in osteosarcoma and preliminarily predicted that the occurrence of osteosarcoma is closely related to pyroptosis, apoptosis, and immune regulation. Predicted Triethyl phosphate, Plinabulin, Siltuximab as potential osteosarcoma treatments.

Inflammasome activation in melanoma progression: the latest update concerning pathological role and therapeutic value

The progression of melanoma is a complex process influenced by both internal and external cues which encourage the transition of tumour cells, uncontrolled growth, migration, and metastasis. Additionally, inflammation allows tumours to evade the immune system, contributing to cancer development. The inflammasome, a complex of many proteins, is crucial in enhancing immune responses to external and internal triggers. As a critical inflammatory mechanism, it contributes to the development of melanoma. These mechanisms may be triggered via various internal and external stimuli, causing the induction of specific enzymes such as caspase-1, caspase-11, or caspase-8. This, in turn, leads to the release of interleukin (IL)-1β and IL-18 and cell death by apoptosis and pyroptosis. Proper inflammasome stimulation is crucial for the host to deal with invading pathogens or tissue injury. However, inappropriate inflammasome stimulation can result in unregulated tissue reactions, thus easing many diseases, including melanoma. Hence, keeping a delicate equilibrium between the stimulation and prohibition of inflammasomes is crucial, necessitating meticulous control of the assembly and functional aspects of inflammasomes. This review examines the latest advancements in inflammasome studies, specifically focusing on the molecular processes that control inflammasome formation, signalling, and modulation in melanoma.

PANoptosis in intestinal epithelium: its significance in inflammatory bowel disease and a potential novel therapeutic target for natural products

The intestinal epithelium, beyond its role in absorption and digestion, serves as a critical protective mechanical barrier that delineates the luminal contents and the gut microbiota from the lamina propria within resident mucosal immune cells to maintain intestinal homeostasis. The barrier is manifested as a contiguous monolayer of specialized intestinal epithelial cells (IEC), interconnected through tight junctions (TJs). The integrity of this epithelial barrier is of paramount. Consequently, excessive IEC death advances intestinal permeability and as a consequence thereof the translocation of bacteria into the lamina propria, subsequently triggering an inflammatory response, which underpins the clinical disease trajectory of inflammatory bowel disease (IBD). A burgeoning body of evidence illustrates a landscape where IEC undergoes several the model of programmed cell death (PCD) in the pathophysiology and pathogenesis of IBD. Apoptosis, necroptosis, and pyroptosis represent the principal modalities of PCD with intricate specific pathways and molecules. Ample evidence has revealed substantial mechanistic convergence and intricate crosstalk among these three aforementioned forms of cell death, expanding the conceptualization of PANoptosis orchestrated by the PNAoptosome complex. This review provides a concise overview of the molecular mechanisms of apoptosis, necroptosis, and pyroptosis. Furthermore, based on the crosstalk between three cell deaths in IEC, this review details the current knowledge regarding PANoptosis in IEC and its regulation by natural products. Our objective is to broaden the comprehension of innovative molecular mechanisms underlying the pathogenesis of IBD and to furnish a foundation for developing more natural drugs in the treatment of IBD, benefiting both clinical practitioners and research workers.

Caspase 3/GSDME-Mediated Corneal Epithelial Pyroptosis Promotes Dry Eye Disease

Purpose

Dry eye disease (DED) is a common ocular surface inflammatory disease with a complex pathogenesis. Herein, the role and effect of gasdermin E (GSDME) in DED pathogenesis were explored.

Methods

In vitro, flow cytometry, Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) release assays were used to determine the effects of hyperosmotic stress on pyroptosis, apoptosis, and cell viability in human corneal epithelial cells (HCECs). Quantitative PCR (qPCR) and Western blot assays were used to detect GSDME expression in HCECs and in those transfected with si-GSDMD. In vivo, GSDMD-knockout (KO) mice were used to study the role of GSDME in DED pathogenesis. The qPCR, Western blotting, and immunofluorescence were used to explore the effects of GSDME on HCEC apoptosis, pyroptosis, and the expression of related genes and proteins in GSDMD-KO mice with scopolamine-induced dry eye.

Results

Pyroptosis and cell membrane rupture occurred, and caspase-3 and GSDME protein expression increased after HCECs were treated with 312 to 500 mOsm sodium chloride. GSDME gene and protein expression levels were increased in HCECs from both si-GSDMD- and GSDMD-KO mice. Although caspase-3 expression was increased in the dry eye group of GSDMD-KO mice, HCEC apoptosis and the apoptosis-related factors PARP were not detected. The gene and protein expression levels of the pyroptosis-related factors ASC and IL-1β were greater than those in GSDMD-KO mice without dry eye.

Conclusions

GSDME is involved in DED pathogenesis by mediating inflammation via the pyroptosis pathway, GSDME inhibition may be a therapeutic target for DED.

Discovery of indole analogue Tc3 as a potent pyroptosis inducer and identification of its combination strategy against hepatic carcinoma

Rationale: Hepatic carcinoma, one of the most malignant cancers in the world, has limited success with immunotherapy and a poor prognosis in patients. While pyroptosis is considered as a promising immunotherapy strategy for tumors, it still suffers from a lack of effective inducers. Methods: We designed, synthesized and screened an indole analogue, Tc3, featuring a 2, 4-thiazolidinedione substituted indole scaffold. Western blotting, qPCR and immunofluorescence were employed to detect the levels of pyroptosis pathway induced by Tc3. RNA sequencing was used to identify the mechanisms of Tc3 in hepatic carcinoma. To validate anti-tumor effect of Tc3, we used CDXs and PDXs mouse models in vivo. Then, the syngeneic effects of Tc3 with cisplatin and anti-PD-1 antibody were verified via western blotting, immunofluorescence, flow cytometry and ELISA. Results: Treatment with Tc3 notably inhibited the growth of hepatic carcinoma both in vitro and in vivo. Mechanistically, Tc3 inhibited the function of PRDX1 and up-regulated excessive ROS. Then, Tc3 induced gasderminE-mediated pyroptosis by activating the endoplasmic reticulum stress. Tumor cells with high expression of GSDME achieved better responses to Tc3-therapy. Tc3 also improved the efficacy of cisplatin against hepatic carcinoma. Additionally, superior synergistic treatment was observed when Tc3 was combined with anti-PD-1 antibody. Notably, Tc3 activated the tumor immune microenvironment (TIME) and enhanced CD8+ T cell infiltration in hepatic carcinoma. Conclusions: Collectively, we identified Tc3 as a promising and effective compound for treating hepatic carcinoma and established its synergistic therapeutic strategy as a pyroptosis inducer.

Interferon gene expression declines over time post-COVID infection and in long COVID patients

BACKGROUND

Interferons (IFNs) represent a first-line defense against viruses and other pathogens. It has been shown that an impaired and uncontrolled release of these glycoproteins can result in tissue damage and explain severe progression of coronavirus disease 2019 (COVID-19). However, their potential role in Long-COVID syndrome (LC) remains debateable.

OBJECTIVES

The objective of the present study is to shed further light on the possible role of IFNs (and related genes) gene expression patterns in the progression of COVID-19 and LC patients.

METHODS

We carried out a multi-cohort study by analyzing the IFN gene expression patterns (using different IFN gene signatures) in five cohorts of acute COVID-19 (n = 541 samples) and LC patients (n = 188), and compared them to patterns observed in three autoimmune diseases (systemic lupus erythematous [n = 242], systemic sclerosis [n = 91], and Sjögren's syndrome [n = 282]).

RESULTS

The data show that, while the interferon signatures are strongly upregulated in severe COVID-19 patients and autoimmune diseases, it decays with the time from symptoms onset and in LC patients. Differential pathway analysis of IFN-related terms indicates an over activation in autoimmune diseases (IFN-I/II) and severe COVID-19 (IFN-I/II/III), while these pathways are mostly inactivated or downregulated in LC (IFN-I/III). By analyzing six proteomic LC datasets, we did not find evidence of a role of IFNs in this condition.

CONCLUSION

Our findings suggest a potential role of cytokine exhaustion mediated by IFN gene expression inactivation as a possible driver of LC.

Poration of mitochondrial membranes by amyloidogenic peptides and other biological toxins

Mitochondria are essential organelles known to serve broad functions, including in cellular metabolism, calcium buffering, signaling pathways and the regulation of apoptotic cell death. Maintaining the integrity of the outer (OMM) and inner mitochondrial membranes (IMM) is vital for mitochondrial health. Cardiolipin (CL), a unique dimeric glycerophospholipid, is the signature lipid of energy-converting membranes. It plays a significant role in maintaining mitochondrial architecture and function, stabilizing protein complexes and facilitating efficient oxidative phosphorylation (OXPHOS) whilst regulating cytochrome c release from mitochondria. CL is especially enriched in the IMM and at sites of contact between the OMM and IMM. Disorders of protein misfolding, such as Alzheimer's and Parkinson's diseases, involve amyloidogenic peptides like amyloid-β, tau and α-synuclein, which form metastable toxic oligomeric species that interact with biological membranes. Electrophysiological studies have shown that these oligomers form ion-conducting nanopores in membranes mimicking the IMM's phospholipid composition. Poration of mitochondrial membranes disrupts the ionic balance, causing osmotic swelling, loss of the voltage potential across the IMM, release of pro-apoptogenic factors, and leads to cell death. The interaction between CL and amyloid oligomers appears to favour their membrane insertion and pore formation, directly implicating CL in amyloid toxicity. Additionally, pore formation in mitochondrial membranes is not limited to amyloid proteins and peptides; other biological peptides, as diverse as the pro-apoptotic Bcl-2 family members, gasdermin proteins, cobra venom cardiotoxins and bacterial pathogenic toxins, have all been described to punch holes in mitochondria, contributing to cell death processes. Collectively, these findings underscore the vulnerability of mitochondria and the involvement of CL in various pathogenic mechanisms, emphasizing the need for further research on targeting CL-amyloid interactions to mitigate mitochondrial dysfunction.

Pyroptosis Signature Gene CHMP4B Regulates Microglia Pyroptosis by Inhibiting GSDMD in Alzheimer's Disease

In this study, we aimed to work through the key genes involved in the process of pyroptosis in Alzheimer's disease (AD) to identify potential biomarkers using bioinformatics technology and further explore the underlying molecular mechanisms. The transcriptome data of brain tissue in AD patients were screened from the GEO database, and pyroptosis-related genes were analyzed. The functions of differential genes were analyzed by enrichment analysis and protein-protein interaction. The diagnostic model was established using LASSO and logistic regression analysis, and the correlation of clinical data was analyzed. Based on single-cell analysis of brain tissues of patients with AD, immunofluorescence and western blotting were used to explore the key cells affected by the hub gene. After GSEA, qRT-PCR, western blotting, LDH, ROS, and JC-1 were used to investigate the potential mechanism of the hub gene on pyroptosis. A total of 15 pyroptosis differentially expressed genes were identified. A prediction model consisting of six genes was established by LASSO and logistic regression analysis, and the area under the curve was up to 0.81. As a hub gene, CHMP4B was negatively correlated with the severity of AD. CHMP4B expression was decreased in the hippocampal tissue of patients with AD and mice. Single-cell analysis showed that CHMP4B was downregulated in AD microglia. Overexpression of CHMP4B reduced the release of LDH and ROS and restored mitochondrial membrane potential, thereby alleviating the inflammatory response during microglial pyroptosis. In summary, CHMP4B as a hub gene provides a new strategy for the diagnosis and treatment of AD.

Analysis of the role of PANoptosis in intervertebral disk degeneration via integrated bioinformatics analysis and experimental validation

Intervertebral disc degeneration (IVDD) is an age-related orthopedic degenerative disease characterized by recurrent episodes of lower back pain, and death of nucleus pulposus cells (NPCs) has been identified as a key factor in the pathophysiological process of IVDD episodes. Recent studies have shown that " PANapoptosis ", a newly characterized form of cell death, has emerged as an important factor contributing to the development of several diseases. However, studies on the specific mechanisms of its role in the development of IVDD are lacking. The aim of this study was to explore the characterization of PANoptosis in IVDD and to identify potential biomarkers and therapeutic targets as well as therapeutic agents. We constructed a PANoptosis gene set, based on the GEO database, and used weighted gene co-expression network analysis (WGCNA) and differential expression analysis to identify PANoptosis genes associated with the pathophysiological process of IVDD episodes by Gene Set Enrichment Analysis (GSEA), immune infiltration, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) to explore the underlying biological mechanisms of PANoptosis and its role in IVDD. Comprehensive bioinformatics analysis showed that seven key genes (APAF1, MEFV, NLRP3, TNF, GSDMD, AIM2, and IRF1) of PANoptosis have good diagnostic value. In addition, we predicted potential therapeutic agents, among which Andrographolide (AG) had the highest correlation and binding affinity to the target. Finally, we performed Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) assays, molecular docking, and cell flow to validate the expression of PANoptosis-related genes and the therapeutic effect of AG. We further divided SD rats into sham-operated, IVDD model, and Andrographolide-treated groups, administered AG at 50 mg/kg via gavage for one month, and observed significant therapeutic effects through HE staining. This study identifies key PANoptosis genes and demonstrates the potential of AG as a therapeutic agent for IVDD.

NOX2 deficiency promotes GSDME-related pyroptosis by reducing AMPK activation in neutrophils

Nicotinamide adenine dinucleotide phosphate oxidase complex 2 (NOX2) is an effector molecule expressed predominantly in neutrophils. Its deficiency is present in immune disorders, including systemic lupus erythematosus, chronic granulomatous disease, and rheumatoid arthritis. Recent reports indicated that NOX2 regulates autoimmunity and programmed cell death. However, the exact mechanism is unclear. In this study, we explored the effect of NOX2 on neutrophil apoptosis. We demonstrated that NOX2 deficiency caused neutrophil pyroptosis. Mechanistically, the NOX2 inhibitor GSK2795039 application or knockdown of NOX2 components resulted in increased mitochondrial ROS, inhibition of AMP-activated protein kinase (AMPK), and activation of Gasdermin E. AMPK activators, metformin and epigallocatechin gallate, inhibited deficient NOX2-induced pyroptosis. Together, these findings illustrate the involvement of NOX2 in regulating neutrophil death and emphasize its importance in autoimmunity.

Immunologic cell deaths: involvement in the pathogenesis and intervention therapy of periodontitis

Periodontitis is one of the most common diseases and primary causes of tooth loss. The main factor that causes periodontitis is an overactive host immunological response. An in-depth investigation into the molecular pathways that cause periodontitis can aid in creating novel therapeutic approaches for periodontitis and its related systemic disorders. Several immunologic cell death (ICD) pathways have been implicated in advancing periodontitis. Nevertheless, there is still a substantial lack of understanding surrounding the precise molecular mechanisms of ICD in periodontitis. Additionally, the beneficial feature of ICD in periodontitis, which involves its ability to eliminate pathogens, needs further confirmation. According to this, a comprehensive literature search utilizing the Web of Science™, PubMed®, and Scopus® databases was conducted. Only items published in the English language up until October 2024 were taken into account, and finally, 65 relevant papers were selected to be included in this review. In this article, we present a comprehensive analysis of the processes and outcomes of ICD activation in the progression of periodontitis. Lastly, the present difficulties linked to ICDs as a viable treatment option for periodontitis are emphasized.

Aflatoxin B1 Promotes Pyroptosis in IPEC-J2 Cells by Disrupting Mitochondrial Dynamics through the AMPK/NLRP3 Pathway

Aflatoxin B1 (AFB1) is one of the most toxic mycotoxins in food and feed, seriously jeopardizing the intestinal health, while the effects of AFB1 on intestinal damage remain to be well understood. This study aims to evaluate the effect of AFB1 on intestinal injury by regulating AMP-activated protein kinase (AMPK)-mediated pyroptosis in vitro. The present study showed that AFB1 led to the formation of large number of bubble-like protrusions on the cell membrane, releasing lactate dehydrogenase (LDH) and interleukin-1β (IL-1β). Stimulation with AFB1 resulted in the activation of the NOD-like receptor protein 3 (NLRP3) pathway, as indicated by the increased expression of pyroptosis-associated factor mRNAs and proteins, which ultimately led to a significant upregulation of the pyroptosis rate. Meanwhile, AFB1 caused dysfunction of mitochondrial dynamics by activating the AMPK signaling pathway as mainly evidenced by upregulating dynamin-1-like protein 1 (Drp1) mRNA and protein expression. Moreover, inhibition of NLRP3 and AMPK pathways by MCC950 and compound C, respectively, significantly alleviated AFB1-induced damage in IPEC-J2 cells, evidenced by suppressed NLRP3-mediated pyroptosis, and ameliorated AMPK-mediated mitochondrial dynamics imbalance. In conclusion, these results demonstrated that AFB1 promoted pyroptosis of IPEC-J2 cells by interfering with mitochondrial dynamics by activating the AMPK/NRLP3 pathway.

Pyroptosis-Inducing Biomaterials Pave the Way for Transformative Antitumor Immunotherapy

Pyroptosis can effectively overcome immunosuppression and reactivate antitumor immunity. However, pyroptosis initiation is challenging. First, the underlying biological mechanisms of pyroptosis are complex, and a variety of gasdermin family proteins can be targeted to induce pyroptosis. Second, other intracellular death pathways may also interfere with pyroptosis. The rationally designed gasdermin protein-targeting biomaterials are capable of inducing pyroptosis and have the capacity to stimulate antitumor immune function in a safe and effective manner. This review provides a comprehensive overview of the design, function, and antitumor efficacy of pyroptosis-inducing materials and the associated challenges, with a particular focus on the design options for pyroptosis-inducing biomaterials based on the activation of different gasdermin proteins. This review offers a valuable foundation for the further development of pyroptosis-inducing biomaterials for clinical applications.

TLR3 Knockdown Attenuates Pressure-Induced Neuronal Damage In Vitro

The disruption of nerve parenchyma and axonal networks triggered by spinal cord injury (SCI) can initiate a cascade of events associated with secondary injury. Toll-like receptors play a critical role in initiating and regulating immune-inflammatory responses following SCI; however, the precise involvement of Toll-like receptor-3 (TLR3) in secondary neuronal injury remains incompletely understood. To investigate the potential contribution of TLR3 in mediating neuronal pressure-induced damage, we established a stress-induced neuronal damage model using rat anterior horn motor neuron line (VSC4.1), which was subjected to varying levels and durations of sustained pressure. Our findings suggest that pressure induces neuronal damage and apoptosis, and reduced proliferation rates in VSC4.1 cells. Furthermore, this pressure-induced neuronal injury is accompanied by upregulation of TLR3 expression and activation of downstream TLR3 signalling molecules. Knockdown experiments targeting TLR3 significantly alleviate pressure-induced motor neuron injury and apoptosis within the anterior horn region while promoting mitochondria-related autophagy and reducing mitochondrial dysfunction via the TLR3/IRF3 and TLR3/NF-κB pathways.

Targeting GSDME-mediated macrophage polarization for enhanced antitumor immunity in hepatocellular carcinoma

Despite the notable efficacy of anti-PD1 therapy in the management of hepatocellular carcinoma (HCC) patients, resistance in most individuals necessitates additional investigation. For this study, we collected tumor tissues from nine HCC patients receiving anti-PD1 monotherapy and conducted RNA sequencing. These findings revealed significant upregulation of GSDME, which is predominantly expressed by tumor-associated macrophages (TAMs), in anti-PD1-resistant patients. Furthermore, patients with elevated levels of GSDME+ macrophages in HCC tissues presented a poorer prognosis. The analysis of single-cell sequencing data and flow cytometry revealed that the suppression of GSDME expression in nontumor cells resulted in a decrease in the proportion of M2-like macrophages within the tumor microenvironment (TIME) of HCC while concurrently augmenting the cytotoxicity of CD8 + T cells. The non-N-terminal fragment of GSDME within macrophages combines with PDPK1, thereby activating the PI3K-AKT pathway and facilitating M2-like polarization. The small-molecule Eliprodil inhibited the increase in PDPK1 phosphorylation mediated by GSDME site 1. The combination of Eliprodil and anti-PD1 was effective in the treatment of both spontaneous HCC in c-Myc + /+;Alb-Cre + /+ mice and in a hydrodynamic tail vein injection model, which provides a promising strategy for novel combined immunotherapy.

Neuroinflammation in Age-Related Neurodegenerative Diseases: Role of Mitochondrial Oxidative Stress

A shared hallmark of age-related neurodegenerative diseases is the chronic activation of innate immune cells, which actively contributes to the neurodegenerative process. In Alzheimer's disease, this inflammatory milieu exacerbates both amyloid and tau pathology. A similar abnormal inflammatory response has been reported in Parkinson's disease, with elevated levels of cytokines and other inflammatory intermediates derived from activated glial cells, which promote the progressive loss of nigral dopaminergic neurons. Understanding the causes that support this aberrant inflammatory response has become a topic of growing interest and research in neurodegeneration, with high translational potential. It has been postulated that the phenotypic shift of immune cells towards a proinflammatory state combined with the presence of immunogenic cell death fuels a vicious cycle in which mitochondrial dysfunction plays a central role. Mitochondria and mitochondria-generated reactive oxygen species are downstream effectors of different inflammatory signaling pathways, including inflammasomes. Dysfunctional mitochondria are also recognized as important producers of damage-associated molecular patterns, which can amplify the immune response. Here, we review the major findings highlighting the role of mitochondria as a checkpoint of neuroinflammation and immunogenic cell deaths in neurodegenerative diseases. The knowledge of these processes may help to find new druggable targets to modulate the inflammatory response.

NLRP3 inflammasome-mitochondrion loop in autism spectrum disorder

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication and the presence of restricted interests and repetitive behavior. To date, no single cause has been demonstrated but both genetic and environmental factors are believed to be involved in abnormal brain development. In recent years, immunological and mitochondrial dysfunctions acquired particular interest in the study of the molecular mechanisms underlying the pathophysiology of ASD. For this reason, our study focused on evaluating the mitochondrial component and activation of the NLRP3 inflammasome, a critical player of the innate immune system. The assembly of NLRP3 with ASC mediates activation of Caspase-1, which in turn, by proteolytic cleavage, activates Gasdermin D and the proinflammatory cytokines IL-1β/IL-18 with their subsequent secretion. Using primary fibroblasts of autistic and control patients we studied basal and stimulated conditions. Specifically, LPS and ATP were used to activate the NLRP3 inflammasome and MCC950 for its inhibition. In addition, FCCP was used as a mitochondrial stressor and MitoTEMPO as a scavenger of mitochondrial ROS. Our results showed a hyperactivation of NLRP3 inflammasome in ASDs, as evidenced by the co-localization of the two main components, NLRP3 and ASC, by the higher levels of ASC specks, oligomers and dimers and by the increased amounts of active Caspase-1 and IL-1β. In addition, increased mitochondrial superoxide anion and reduced mitochondrial membrane potential were detected in ASD cells. These data are in accordance with the abnormal mitochondrial morphology evidenced by transmission electron microscopy analysis. Interestingly, NLRP3 inflammasome inhibition with MCC950 improved mitochondrial parameters, while the use of MitoTEMPO, in addition to decrease mitochondrial ROS production, was able to prevent NLRP3 inflammasome activation suggesting for the first time an abnormal bidirectional crosstalk between mitochondria and NLRP3 inflammasome in ASD.

USP14 modulates cell pyroptosis and ameliorates doxorubicin-induced cardiotoxicity by deubiquitinating and stabilizing SIRT3

This study investigates the role of the deubiquitinating enzyme USP14 in alleviating doxorubicin (DOX)-induced cardiotoxicity (DIC), particularly concerning its mechanism of regulating pyroptosis through the stabilization of the mitochondrial protein SIRT3. Using in vivo and in vitro models, the research demonstrated that USP14 overexpression protects against DOX-induced cardiac damage by modulating pyroptosis. Silencing SIRT3 via siRNA revealed that SIRT3 is a key intermediary molecule in USP14-mediated regulation of pyroptosis. Notably, DOX exposure resulted in decreased USP14 expression, while its overexpression preserved mitochondrial function and reduced oxidative stress by stabilizing SIRT3. Immunoprecipitation confirmed that USP14 stabilizes SIRT3 through deubiquitination. These findings position USP14 as a promising therapeutic target for mitigating DOX-induced cardiotoxicity by stabilizing SIRT3 and maintaining mitochondrial integrity, suggesting potential novel strategies for cardio-protection in chemotherapy.

The Potential Therapeutic Prospect of PANoptosis in Heart Failure

Heart failure (HF) represents a serious manifestation or advanced stage of various cardiac diseases. HF continues to impose a significant global disease burden, characterized by high rates of hospitalization and fatality. Furthermore, the pathogenesis and pathophysiological processes underlying HF remain incompletely understood, complicating its prevention and treatment strategies. One significant pathophysiological mechanism associated with HF is the systemic inflammatory response. PANoptosis, a novel mode of inflammatory cell death, has been extensively studied in the context of infectious diseases, neurodegenerative disorders, cancers, and other inflammatory conditions. Recent investigations have revealed that PANoptosis-related genes are markedly dysregulated in HF specimens. Consequently, the PANoptosis-mediated inflammatory response may represent a potential mechanism and therapeutic target for HF. This paper conducts a comprehensive analysis of the molecular pathways that drive PANoptosis. We discuss its role and potential therapeutic targets in HF, thereby providing valuable insights for clinical treatment and the development of novel therapies.

The role of pyroptosis in cancer: key components and therapeutic potential

Pyroptosis is a lytic and inflammatory form of gasdermin protein-mediated programmed cell death that is typically initiated by inflammasomes. The inflammasome response is an effective mechanism for eradicating germs and cancer cells in the event of cellular injury. The gasdermin family is responsible for initiating pyroptosis, a process in which holes are made in the cell membrane to allow inflammatory chemicals to escape. Mounting evidence indicates that pyroptosis is critical for controlling the development of cancer. In this review, we provide a general overview of pyroptosis, examine the relationship between the primary elements of pyroptosis and tumors, and stress the necessity of pyroptosis-targeted therapy in tumors. Furthermore, we explore its dual nature as a double-edged sword capable of both inhibiting and facilitating the growth of cancer, depending on the specific conditions. Ultimately, pyroptosis is a phenomenon that has both positive and negative effects on tumors. Using this dual impact in a reasonable manner may facilitate investigation into the initiation and progression of tumors and offer insights for the development of novel treatments centered on pyroptosis.

Ochratoxin A in Poultry Supply Chain: Overview of Feed Occurrence, Carry-Over, and Pathognomonic Lesions in Target Organs to Promote Food Safety

Ochratoxin A (OTA) is a mycotoxin produced by fungi species belonging to the genera Aspergillus spp. and Penicillium spp. The proliferation of OTA-producing fungal species may occur due to inadequate practices during both the pre-harvest and post-harvest stages of feed. Consequently, poultry species may be exposed to high concentrations of this mycotoxin that can be transferred to animal tissues due to its carry-over, reaching dangerous concentrations in meat and meat products. Therefore, this review aims to propose a comprehensive overview of the effects of OTA on human health, along with data from global studies on the prevalence and concentrations of this mycotoxin in avian feeds, as well as in poultry meat, edible offal, and eggs. Moreover, the review examines significant gross and histopathological lesions in the kidneys and livers of poultry linked to OTA exposure. Finally, the key methods for OTA prevention and decontamination of feed are described.

Interactions between tumor-associated macrophages and regulated cell death: therapeutic implications in immuno-oncology

Tumor-associated macrophages (TAMs) play a pivotal role in sculpting the tumor microenvironment and influencing cancer progression, particularly through their interactions with various forms of regulated cell death (RCD), including apoptosis, pyroptosis, ferroptosis, and necroptosis. This review examines the interplay between TAMs and these RCD pathways, exploring the mechanisms through which they interact to promote tumor growth and advancement. We examine the underlying mechanisms of these intricate interactions, emphasizing their importance in cancer progression and treatment. Moreover, we present potential therapeutic strategies for targeting TAMs and manipulating RCD to enhance anti-tumor responses. These strategies encompass reprogramming TAMs, inhibiting their recruitment, and selectively eliminating them to enhance anti-tumor functions, alongside modulating RCD pathways to amplify immune responses. These insights offer a novel perspective on tumor biology and provide a foundation for the development of more efficacious cancer therapies.

Gasdermin E mediates pyroptosis in the progression of hepatocellular carcinoma: a double-edged sword

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer worldwide. It usually develops due to viral hepatitis or liver cirrhosis. The molecular mechanisms involved in HCC pathogenesis are complex and incompletely understood. Gasdermin E (GSDME) is a tumor suppressor gene and is inhibited in most cancers. Recent studies have reported that, unlike those in most tumors, GSDME is highly expressed in liver cancer, and GSDME expression in HCC is negatively associated with prognosis, suggesting that GSDME may promote HCC. However, antitumor drugs can induce pyroptosis through GSDME, killing HCC cells. Therefore, GSDME may both inhibit and promote HCC development. Because functional studies of GSDME in HCC are limited, the precise molecular mechanisms of GSDME in liver cancer remain unclear. In this article, we have reviewed the role, related mechanisms, and clinical importance of GSDME at the onset and development of HCC to provide a theoretical foundation to improve the clinical diagnosis and treatment of liver cancer.

Gastrodenol suppresses NLRP3/GSDMD mediated pyroptosis and ameliorates inflammatory diseases

Pyroptosis, a form of inflammatory programmed cell death, plays a pivotal role in the pathogenesis of various diseases. This process is primarily mediated by the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing protein 3 (NLRP3). Gastrodenol (Bismuth tripotassium dicitrate, GAS) is a mineral compound which is used to treat duodenal and gastric ulcers associated with Helicobacter pylori. In this study, GAS was found to exhibit protective effects against classical pyroptosis in macrophages. Specifically, GAS effectively inhibits the activation of the NLRP3 inflammasome, Gasdermin D (GSDMD)-mediated pyroptosis, and the secretion of pro-inflammatory cytokines. Mechanistically, GAS inhibited NLRP3 oligomerization and reduced the oligomerization of adaptor protein apoptosis-associated speck like protein containing a caspase activation and recruitment domain (ASC) by directly binding to NLRP3. The interaction between GAS and NLRP3 is primarily mediated through hydrogen bonding and hydrophobic forces. Hydrogen bonds are formed with PHE-727, LEU-723, and ASP-700. Remarkably, GAS treatment attenuated pyroptosis-mediated inflammatory diseases, including experimental autoimmune encephalomyelitis (EAE), lipopolysaccharide (LPS)-induced septic, and monosodium urate (MSU)-induced peritonitis in mice. To conclude, this is the first report that discovered clinical old medicine GAS as a potent inhibitor of pyroptosis and propose a novel therapeutic strategy for the prevention and treatment of NLRP3-GSDMD mediated diseases.

GSDME promotes MASLD by regulating pyroptosis, Drp1 citrullination-dependent mitochondrial dynamic, and energy balance in intestine and liver

Dysregulated metabolism, cell death, and inflammation contribute to the development of metabolic dysfunction-associated steatohepatitis (MASH). Pyroptosis, a recently identified form of programmed cell death, is closely linked to inflammation. However, the precise role of pyroptosis, particularly gasdermin-E (GSDME), in MASH development remains unknown. In this study, we observed GSDME cleavage and GSDME-associated interleukin-1β (IL-1β)/IL-18 induction in liver tissues of MASH patients and MASH mouse models induced by a choline-deficient high-fat diet (CDHFD) or a high-fat/high-cholesterol diet (HFHC). Compared with wild-type mice, global GSDME knockout mice exhibited reduced liver steatosis, steatohepatitis, fibrosis, endoplasmic reticulum stress, lipotoxicity and mitochondrial dysfunction in CDHFD- or HFHC-induced MASH models. Moreover, GSDME knockout resulted in increased energy expenditure, inhibited intestinal nutrient absorption, and reduced body weight. In the mice with GSDME deficiency, reintroduction of GSDME in myeloid cells-rather than hepatocytes-mimicked the MASH pathologies and metabolic dysfunctions, as well as the changes in the formation of neutrophil extracellular traps and hepatic macrophage/monocyte subclusters. These subclusters included shifts in Tim4+ or CD163+ resident Kupffer cells, Ly6Chi pro-inflammatory monocytes, and Ly6CloCCR2loCX3CR1hi patrolling monocytes. Integrated analyses of RNA sequencing and quantitative proteomics revealed a significant GSDME-dependent reduction in citrullination at the arginine-114 (R114) site of dynamin-related protein 1 (Drp1) during MASH. Mutation of Drp1 at R114 reduced its stability, impaired its ability to redistribute to mitochondria and regulate mitophagy, and ultimately promoted its degradation under MASH stress. GSDME deficiency reversed the de-citrullination of Drp1R114, preserved Drp1 stability, and enhanced mitochondrial function. Our study highlights the role of GSDME in promoting MASH through regulating pyroptosis, Drp1 citrullination-dependent mitochondrial function, and energy balance in the intestine and liver, and suggests that GSDME may be a potential therapeutic target for managing MASH.

The regulation of pyroptosis by post-translational modifications: molecular mechanisms and therapeutic targets

Pyroptosis, a type of programmed cell death mediated by gasdermin family proteins, releases a large amount of immune stimulatory substances, which further contribute to inflammation and elicit an adaptive immune response against tumours and pathogens. And it occurs through multiple pathways that involve the activation of specific caspases and the cleavage of gasdermins. Post-translational modifications (PTMs) could influence the chemical properties of the modified residues and neighbouring regions, ultimately affecting the activity, stability, and functions of proteins to regulate pyroptosis. Many studies have been conducted to explore the influence of PTMs on the regulation of pyroptosis. In this review, we provide a comprehensive summary of different types of PTMs that influence pyroptosis, along with their corresponding modifying enzymes. Moreover, it elaborates on the specific contributions of different PTMs to pyroptosis and delves into how the regulation of these modifications can be leveraged for therapeutic interventions in cancer and inflammatory diseases.

Proteasome inhibition induces apoptosis through simultaneous inactivation of MCL-1/BCL-XL by NOXA independent of CHOP and JNK pathways

Proteasome inhibitors have been employed in the treatment of relapsed multiple myeloma and mantle cell lymphoma. The observed toxicity caused by proteasome inhibitors is a universal phenotype in numerous cancer cells with different sensitivity. In this study, we investigate the conserved mechanisms underlying the toxicity of the proteasome inhibitor bortezomib using gene editing approaches. Our findings utilizing different caspase knocking out cells reveal that bortezomib induces classic intrinsic apoptosis by activating caspase-9 and caspase-3/7, leading to pore-forming protein GSDME cleavage and subsequent lytic cell death or called secondary necrosis, a phenotype also observed in many apoptosis triggers like TNFα plus CHX, DTT and tunicamycin treatment in HeLa cells. Furthermore, through knocking out of nearly all BH3-only proteins including BIM, BAD, BID, BMF and PUMA, we demonstrate that NOXA is the sole BH3-only protein responsible for bortezomib-induced apoptosis. Of note, NOXA is well known for selectively binding to MCL-1 and A1, but our studies utilizing different BH3 mimetics as well as immunoprecipitation assays indicate that, except for the constitutive interaction of NOXA with MCL-1, the accumulation of NOXA after bortezomib treatment allows it to interact with BCL-XL, then simultaneous relieving suppression on apoptosis by both anti-apoptotic proteins BCL-XL and MCL-1. In addition, though bortezomib-induced significant ER stress and JNK activation were observed in the study, further genetic depletion experiments prove that bortezomib-induced apoptosis occurs independently of ER stress-related apoptosis factor CHOP and JNK. In summary, these results provide a solid conclusion about the critical role of NOXA in inactivation of BCL-XL except MCL-1 in bortezomib-induced apoptosis.

Triggering Pyroptosis by Doxorubicin-Loaded Multifunctional Nanoparticles in Combination with Decitabine for Breast Cancer Chemoimmunotherapy

Pyroptosis, a form of programmed cell death, holds great promise for breast cancer treatment. However, the downregulation of gasdermin E (GSDME) limits the effectiveness of pyroptosis. To address this challenge, we developed a folic acid-modified and glutathione/reactive oxygen species dual-responsive nanocarrier (FPSD NPs) for the targeted delivery of doxorubicin (DOX). Through the combination with DNA methyltransferase inhibitor decitabine (DAC), the GSDME protein expression was significantly increased in 4T1 cells, resulting in cell swelling and ballooning, which are characteristic features of pyroptosis. In vivo experiments further demonstrated the antitumor efficacy of DAC + DOX@FPSD NPs, and the 4T1-bearing mice treated with DAC + DOX@FPSD NPs exhibited reduced tumor volumes, minimized tumor weights, decreased Ki67-positive cells, increased TUNEL apoptosis ratios, and pronounced lesions in H&E staining. Furthermore, DAC + DOX@FPSD NP treatment could promote pyroptosis-associated antitumor immunity, as evidenced by the increased presence of CD3+, CD4+, and CD8+ T cells, heightened secretion of tumor necrosis factor-α and interferon-γ, elevated high-mobility group box-1 levels, and enhanced calreticulin exposure. The FPSD nanocarrier developed in this study had favorable stability, active targeting ability, biocompatibility, and controlled release properties, and the DAC + DOX@FPSD NPs represented an approach to antitumor therapy by inducing pyroptosis, which offers a promising avenue for breast cancer treatment.

Advancing Roles and Therapeutic Potentials of Pyroptosis in Host Immune Defenses against Tuberculosis

Tuberculosis (TB), an infectious disease caused by Mycobacterium tuberculosis (Mtb) infection, remains a deadly global public health burden. The use of recommended drug combinations in clinic has seen an increasing prevalence of drug-resistant TB, adding to the impediments to global control of TB. Therefore, control of TB and drug-resistant TB has become one of the most pressing issues in global public health, which urges the exploration of potential therapeutic targets in TB and drug-resistant TB. Pyroptosis, a form of programmed cell death characterized by cell swelling and rupture, release of cellular contents and inflammatory responses, has been found to promote pathogen clearance and adopt crucial roles in the control of bacterial infections. It has been demonstrated that Mtb can cause host cell pyroptosis, and these host cells, which are infected by Mtb, can kill Mtb accompanied by pyroptosis, while, at the same time, pyroptosis can also release intracellular Mtb, which may potentially worsen the infection by exacerbating the inflammation. Here, we describe the main pathways of pyroptosis during Mtb infection and summarize the identified effectors of Mtb that regulate pyroptosis to achieve immune evasion. Moreover, we also discuss the potentials of pyroptosis to serve as an anti-TB therapeutic target, with the aim of providing new ideas for the development of TB treatments.

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.

Receptor-interacting protein kinase 1 confers autophagic promotion of gasdermin E-mediated pyroptosis in aristolochic acid-induced acute kidney injury

Aristolochic acid (AA) exposure is a severe public health concern worldwide. AAs damage the kidney with an inevitable acute phase that is similar to acute kidney injury (AKI). Gasdermin E (GSDME) is abundant in the kidney; thus; it-mediated pyroptosis might be essential in connecting cell death and inflammation and promoting AAs-AKI. However, the role and exact mechanism of pyroptosis in AAs-AKI have not been investigated. In this study, aristolochic acid I (AAI) was used to establish AKI models. The expression and translocation results showed GSDME-mediated pyroptosis in AAI-AKI. Knocking down GSDME attenuated AAI-induced cell death and transcription of proinflammatory cytokines. Mechanistic research inhibiting caspase (casp) 3, casp 8, and casp 9 with specific chemical antagonists demonstrated that GSDME was activated by cleaved casp 3. Furthermore, the kinase activity of upstream receptor-interacting protein kinase 1 (RIPK1) was significantly elevated, and inhibiting RIPK1 with specific inhibitors markedly improved AAI-induced cell damage. In addition, the level of autophagy was obviously increased. Pretreatment with a specific autophagic inhibitor (3-methyladenine) or knockdown of autophagic genes (Atg5 or Atg7) evidently reduced the activity of RIPK1 and downstream apoptosis and pyroptosis, thus attenuating AA-induced cell injury, which suggested that RIPK1 was a novel link conferring autophagic promotion of pyroptosis. These findings reveal GSDME-mediated pyroptosis for the first time in AAI-induced AKI, propose its novel role in the transcription of cytokines, and demonstrate that autophagy promotes pyroptosis via the RIPK1-dependent apoptotic pathway. This study promotes the understanding of the toxic effects and exact mechanisms of AAs. This will contribute to evaluating the environmental risk of AA exposure and might provide potential therapeutic targets for AA-AKI.

Permeabilization of the outer mitochondrial membrane: Mechanisms and consequences

Permeabilization of the outer mitochondrial membrane is а physiological process that can allow certain molecules to pass through it, such as low molecular weight solutes required for cellular respiration. This process is also important for the development of various modes of cell death. Depending on the severity of this process, cells can die by autophagy, apoptosis, or necrosis/necroptosis. Distinct types of pores can be opened at the outer mitochondrial membrane depending on physiological or pathological stimuli, and different mechanisms can be activated in order to open these pores. In this comprehensive review, all these types of permeabilization, the mechanisms of their activation, and their role in various diseases are discussed.

DAMP sensing and sterile inflammation: intracellular, intercellular and inter-organ pathways

Damage-associated molecular patterns (DAMPs) are endogenous molecules that are released from host cells as a result of cell death or damage. The release of DAMPs in tissues is associated with loss of tissue homeostasis. Sensing of DAMPs by innate immune receptors triggers inflammation, which can be beneficial in initiating the processes that restore tissue homeostasis but can also drive inflammatory diseases. In recent years, the sensing of intracellular DAMPs has received extensive attention in the field of sterile inflammation. However, emerging studies have shown that DAMPs that originate from neighbouring cells, and even from distal tissues or organs, also mediate sterile inflammatory responses. This multi-level sensing of DAMPs is crucial for intercellular, trans-tissue and trans-organ communication. Here, we summarize how DAMP-sensing receptors detect DAMPs from intracellular, intercellular or distal tissue and organ sources to mediate sterile inflammation. We also discuss the possibility of targeting DAMPs or their corresponding receptors to treat inflammatory diseases.

Antagonistic nanobodies implicate mechanism of GSDMD pore formation and potential therapeutic application

Inflammasome activation results in the cleavage of gasdermin D (GSDMD) by pro-inflammatory caspases. The N-terminal domains (GSDMDNT) oligomerize and assemble pores penetrating the target membrane. As methods to study pore formation in living cells are insufficient, the order of conformational changes, oligomerization, and membrane insertion remained unclear. We have raised nanobodies (VHHs) against human GSDMD and find that cytosolic expression of VHHGSDMD-1 and VHHGSDMD-2 prevents oligomerization of GSDMDNT and pyroptosis. The nanobody-stabilized GSDMDNT monomers partition into the plasma membrane, suggesting that membrane insertion precedes oligomerization. Inhibition of GSDMD pore formation switches cell death from pyroptosis to apoptosis, likely driven by the enhanced caspase-1 activity required to activate caspase-3. Recombinant antagonistic nanobodies added to the extracellular space prevent pyroptosis and exhibit unexpected therapeutic potential. They may thus be suitable to treat the ever-growing list of diseases caused by activation of (non-) canonical inflammasomes.