The gasdermins, a protein family executing cell death and inflammation

Gasdermin E links tumor cell-intrinsic nucleic acid signaling to proinflammatory cell death for successful checkpoint inhibitor cancer immunotherapy

Durable clinical responses to immune checkpoint inhibitors (ICI) are limited to a minority of patients, and molecular pathways that modulate their efficacy remain incompletely defined. We have recently shown that activation of the innate RNA-sensing receptor RIG-I and associated apoptotic tumor cell death can facilitate tumor immunosurveillance and -therapy, but the mechanism that drives its immunogenicity remained unclear. We here show that intratumoral activity of the pore-forming protein gasdermin E (GSDME) links active RIG-I signaling and apoptotic cell death in tumor cells to inflammatory pyroptosis. Activation of tumor-intrinsic RIG‑I triggered cleavage of GSDME, pore formation, loss of cell membrane integrity and leakage of cytosolic components from dying tumor cells. Tumor antigen cross-presentation by dendritic cells and subsequent expansion of cytotoxic T cells strongly relied on tumor-intrinsic GSDME activity. In preclinical murine cancer models, defective GSDME signaling rendered tumors resistant to ICI therapy. Epigenetic reprogramming with upregulation of Gdsme enhanced the susceptibility of tumor cells to inflammatory cell death and immunotherapy. In humans, transcriptome analysis of melanoma samples showed strong correlation between genetic activity of the RIG-I and pyroptosis pathways. In melanoma patients, high transcriptional activity of a pyroptosis gene set was associated with prolonged survival and beneficial response to ICI therapy. In summary, our data show that GSDME links RIG-I and apoptotic signaling to inflammatory cell death, thereby driving its immunogenicity and responsiveness to ICI. A deeper understanding of these pathways may allow for the development of novel combined modality approaches to improve ICI treatment responses in cancer patients.

Targeting programmed cell death pathways in gastric cancer: a focus on pyroptosis, apoptosis, necroptosis and PANoptosis

Gastric cancer (GC) is recognized as one of the most prevalent and serious malignancies, distinguished by its high incidence and fatality rates. Given the considerable mortality rate associated with GC, it is imperative to clarify the related pathways of GC development and further identify feasible targets for rational targeted therapy. Accumulating evidence reveals that programmed cell death (PCD) is a crucial element in both the progression and treatment of cancer. Pyroptosis, apoptosis, and necroptosis are three well-studied types of PCD, and a link between them and GC has been established in recent studies. PANoptosis, a comparatively novel type of PCD, shares key traits with pyroptosis, apoptosis, and necroptosis, yet cannot be entirely illustrated by any single model. PANoptosis has been discovered to exert an impact on multiple diseases, including cancer, infections, and inflammatory conditions, consequently offering novel perceptions into the progression and treatment of GC. This review seeks to encapsulate the emerging roles and therapeutic potential of pyroptosis, apoptosis, necroptosis, and PANoptosis in GC, laying the groundwork for the advancement of innovative treatment methods that target important signaling pathways connected with these four forms of PCD.

Two-photon photosensitizer for specific targeting and induction of tumor pyroptosis to elicit systemic immunity-boosting anti-tumor therapy

Photodynamic therapy (PDT) has garnered increasing attention in cancer treatment due to its precise spatiotemporal selectivity and non-invasive nature. However, several challenges, including the inability of photosensitizers to discriminate between tumor and healthy tissues, as well as the limited tissue penetration depth of light sources, impede its broader application. To surmount these impediments, our research introduces a two-photon photosensitizer (TPSS) that specifically targets tumor overexpressing carbonic anhydrase IX (CA IX), thereby exhibiting exceptional specificity for tumor cells. Under two-photon laser stimulation, TPSS generates a large amount of reactive oxygen species (ROS), inducing cell pyroptosis and subsequently triggering a strong anti-tumor immune response. Additionally, proteomics analysis provides compelling evidence to elucidate the anti-tumor mechanism of TPSS in vivo. Through comprehensive immune assessments, TPSS under two-photon laser irradiation effectively activates both the innate and adaptive immune systems, efficiently suppressing the proliferation of distant metastatic tumors, underscoring its considerable therapeutic potential. Collectively, this study provides a viable strategy to overcome the limitations of PDT, highlighting the prospects of two-photon excitation photosensitizers.

Newcastle Disease Virus Induces Pyroptosis in Canine Mammary Tumour CMT-U27 Cells via the TNFα/NF-κB/NLRP3 Signalling Pathway

Mammary tumours are the most common type of neoplasm in female dogs, with nearly half being malignant. Oncolytic Newcastle disease virus (NDV) therapy has emerged as a novel cancer treatment option; however, its precise oncolytic mechanism in canine mammary tumours (CMT) remain unclear. Ultrastructural analysis of NDV-infected CMT-U27 cells with locally damaged cell membranes and swollen and ruptured mitochondria revealed the occurrence of pyroptosis. Transcriptome sequencing further identified a significant upregulation of pyroptosis-related genes, including NLRP1, NOD2, caspase-1, and GSDMD. Subsequent examination of RNA and protein expression levels of pyroptosis-related molecules in vitro indicated that NDV induces pyroptosis in CMT-U27 cells via the caspase-1/GSDMD pathway. Additionally, inhibition of the TNFα/NF-κB pathway and knockdown of NOD-like receptor pyrin domain-containing protein 3 (NLRP3) using small interfering RNA demonstrated that the TNFα/NF-κB pathway can regulate NDV-induced pyroptosis through the NLRP3 inflammasome. In a xenograft model, intravenous administration of NDV significantly inhibited tumour growth, and prolonged the survival time in nude mice bearing CMT-U27 cells. NDV treatment enhances intratumoural pyrotosis in tumour bearing mice. In conclusion, these findings suggest that NDV induces pyroptosis in CMT-U27 cells through the TNFα/NF-κB/NLRP3 pathway, providing a foundation for future research into NDV's therapeutic potential in canine mammary cancer.

Machine Learning and Experiments Revealed Key Genes Related to PANoptosis Linked to Drug Prediction and Immune Landscape in Spinal Cord Injury

Spinal cord injury (SCI) is a severe central nervous system injury without effective therapies. PANoptosis is involved in the development of many diseases, including brain and spinal cord injuries. However, the biological functions and molecular mechanisms of PANoptosis-related genes in spinal cord injury remain unclear. In the bioinformatics analysis of public data of SCI, the differentially expressed genes (DEGs) identified by GSE151371 were hybridized with PANoptosis-related genes (PRGs) to obtain differentially expressed PANoptosis-related genes (DE-PRGs). Through three machine learning algorithms, we obtained the hub genes. Then, we constructed functional analysis, drug prediction, regulatory network construction, and immune infiltrating cell analysis. Finally, the expression of the hub gene was verified in GSE93561, GSE45376, and qRT-PCR analysis. Through the above analysis, 14 DE-PRGs were obtained by intersecting 3582 DEGs with 46 PRGs. Five key hub genes, CASP4, GSDMB, NAIP, NLRC4, and NLRP3, were obtained by 3 machine learning algorithms. All five hub genes were enriched in phagocytosis mediated by FC GAMMA R. The 11 immune cells were significantly different between spinal cord injury (SCI) group and human control (HC) group, such as mast cell and gamma delta T cell. The transcription factor (TF)-hub gene network contained 10-nodes (4 hub genes and 6 TFs) and 8-edges. The miRNA-hub gene network consisting of 5-nodes (3 hub genes and 2 miRNAs) and 3-edges was constructed. Moreover, the CASP4 predicted 1 small molecule drug and NLRP3 predicted 9 small molecule drugs. Finally, the expression of 5 hub genes were significantly different in GSE45376 and GSE93561 (SCI vs. HC) and mice SCI model (Sham vs. SCI). Collectively, we identified 5 hub genes (CASP4, GSDMB, NAIP, NLRC4, and NLRP3) associated with PANoptosis, providing potential directions for treating spinal cord injury.

Role of Pyroptosis in inflammatory bowel disease

Inflammatory bowel disease (IBD) is a serious chronic condition marked by persistent and recurrent intestinal ulcers. Although the exact cause of IBD remains unclear, it is generally accepted that a complex interaction among dietary factors, gut microbiota, and immune responses in genetically predisposed individuals contributes to its development. Pyroptosis, an inflammatory form of programmed cell death activated by inflammasomes, is marked by the rupture of cell membranes and the subsequent release of inflammatory mediators. Emerging evidence indicates that pyroptosis plays a crucial role in the pathogenesis of IBD. Moderate pyroptosis activation can enhance intestinal immune defenses, while excessive inflammasome activation can trigger an inflammatory cascade, resulting in increased damage to intestinal tissues. This article reviews the molecular mechanisms underlying pyroptosis and highlights its role in the onset and progression of IBD. Furthermore, We explore recent advancements in IBD treatment, focusing on small molecule compounds that specifically target and inhibit pyroptosis.

Crosstalk between autophagy and other forms of programmed cell death

Cell death occurs continuously throughout individual development. By removing damaged or senescent cells, cell death not only facilitates morphogenesis during the developmental process, but also contributes to maintaining homeostasis after birth. In addition, cell death reduces the spread of pathogens by eliminating infected cells. Cell death is categorized into two main forms: necrosis and programmed cell death. Programmed cell death encompasses several types, including autophagy, pyroptosis, apoptosis, necroptosis, ferroptosis, and PANoptosis. Autophagy, a mechanism of cell death that maintains cellular equilibrium via the breakdown and reutilization of proteins and organelles, is implicated in regulating almost all forms of cell death in pathological contexts. Notably, necroptosis, ferroptosis, and PANoptosis are directly classified as autophagy-mediated cell death. Therefore, regulating autophagy presents a therapeutic approach for treating diseases such as inflammation and tumors that arise from abnormalities in other forms of programmed cell death. This review focuses on the crosstalk between autophagy and other programmed cell death modalities, providing new perspectives for clinical interventions in inflammatory and neoplastic diseases.

miR-126-5p protects from URSA via inhibiting Caspase-1-dependent pyroptosis of trophoblast cells

Unexplained recurrent spontaneous abortion (URSA) is a distressing pregnancy complication that seriously threat to women's reproductive health. Trophoblast pyroptosis was involved in the occurrence of URSA, but the potential mechanism remains unclear. In this work, we found CASP1 transcription and the level of pyroptosis were significantly elevated in the villous tissues of URSA patients. Suppression of cell pyroptosis by Gasdermin-D (GSDMD) or Caspase-1 inhibitors can reduce embryo resorption rate of URSA mice, while Caspase-1 over-expression in normal pregnant (NP) mice can aggravate embryo resorption. Meanwhile, a pronounced decline in the expression of microRNA-126-5p (miR-126-5p) was found in URSA patients, which was inversely related to CASP1 expression. Over-expression of miR-126-5p restrained trophoblast pyroptosis via inhibiting Caspase-1/GSDMD signaling pathway by direct binding to 3'-UTR of CASP1. Moreover, experiments in vivo substantiated that up-regulation of miR-126-5p effectively suppressed Caspase-1-mediated pyroptosis in placental tissue and significantly reduced embryo resorption rate. Collectively, these results underscored that diminished miR-126-5p expression plays a crucial role in URSA by enhancing trophoblast pyroptosis through activating Caspase-1/GSDMD signaling pathway. As a result, miR-126-5p shows significant promise as a possible biomarker for diagnosis and treatment of URSA.

Predesigned DNA Origami Nanodrills Mediate Controlled Pore Formation on a Plasma Membrane and Cell Death

We presented an engineered DNA origami nanodrill that is capable of controlled attachment and penetration of the plasma membrane, thereby inducing cell damage and lytic death. The cap-and-stem-like DNA origami nanodrills were constructed, equipping them with addressable cholesterol tags on their caps for adherence to lipid bilayers. The subsequent insertion of the origami stems was initiated, enabling the generation of distinct transmembrane channels in various artificial and biological membranes. These nanodrills with plasma-membrane-disrupting functions resulted in mechanical damage to living cell membranes, leading to increased cytosolic calcium levels, enhanced intracellular protein release, and potent cytotoxicity against tumor cells. The further stimuli-responsive design enabled acid-triggered attachment of DNA nanodrills to the plasma membrane and subsequent cell damage in a pH-controlled fashion. This programmable origami nanodrill could serve as an artificial mediator of plasma-membrane rupture and cell death, thus potentially leading to the development of new therapeutic strategies to combat cancer.

Sonodynamic Therapy Induces Pyroptosis and Recruits CAR-NK Cells to Enhance the Treatment of Oral Squamous Cell Carcinoma

Background: Immunotherapy strategies have demonstrated promising efficacy in treating various cancers. However, cancer cells often evade immune surveillance by reducing their immunogenicity, which limits immune cell infiltration into the tumor microenvironment. Pyroptosis, a proinflammatory form of programmed cell death, is characterized by the formation of plasma membrane pores that lead to the release of intracellular contents and stimulate a robust immune response. Results: To exploit this mechanism, we developed hematoporphyrin monomethyl ether (HMME)-loaded nanoliposomes capable of efficiently accumulating at the tumor site. Upon ultrasound irradiation, these nanomedicines generate reactive oxygen species (ROS) that activate Caspase-3, which cleaves Gasdermin E (GSDME) and induces tumor cell pyroptosis. Notably, this sonodynamic therapy (SDT) based on nanosonosensitizers enhanced the targeted enrichment of chimeric antigen receptor (CAR)-engineered natural killer (NK) cells at the ultrasound-irradiated tumor site, significantly improved the tumor immune response, and effectively inhibited the growth and proliferation of oral squamous cell carcinoma (OSCC) cells both in vivo and in vitro. Conclusions: Given that NK cell immunotherapy has an excellent safety profile with minimal risks of cytokine release syndrome and neurotoxicity, this approach holds promise as an adjunct to various NK cell-based immunotherapies through SDT-induced pyroptosis.

Pyrazolo[1,5-a]pyrimidine-Based Type-I Photosensitizer as an Efficient Pyroptosis Inducer for Tumor Ablation

Pyroptosis is a proinflammatory and lytic programmed cell death form, which can promote cytotoxic T lymphocyte (CTL) maturation and tumor infiltration through the release of damage-associated molecular patterns (DAMPs). Therefore, the induction of pyroptosis by small molecules is a promising strategy to activate antitumor immunity. In this work, we report the design of a new class of pyrazolo[1,5-a]pyrimidine-based type-I photosensitizers (PSs) as efficient pyroptosis inducers for cancer photodynamic therapy (PDT). Among the compounds, ZS-3 exhibited the most excellent reactive oxygen species (ROS) generation ability and phototoxicity in vitro. It was found that ZS-3 induced cell pyroptosis through the caspase-3/gasdermin E (GSDME) pathway under light irradiation, characterized by bubble formation and damage-associated molecular pattern release. Furthermore, ZS-3 lipid nanoparticles significantly inhibited tumor growth and evoked antitumor immune responses in vivo.

Targeting pyroptosis for cancer immunotherapy: mechanistic insights and clinical perspectives

Pyroptosis is a distinct form of programmed cell death characterized by the rupture of the cell membrane and robust inflammatory responses. Increasing evidence suggests that pyroptosis significantly affects the tumor microenvironment and antitumor immunity by releasing damage-associated molecular patterns (DAMPs) and pro-inflammatory mediators, thereby establishing it as a pivotal target in cancer immunotherapy. This review thoroughly explores the molecular mechanisms underlying pyroptosis, with a particular focus on inflammasome activation and the gasdermin family of proteins (GSDMs). It examines the role of pyroptotic cell death in reshaping the tumor immune microenvironment (TIME) involving both tumor and immune cells, and discusses recent advancements in targeting pyroptotic pathways through therapeutic strategies such as small molecule modulators, engineered nanocarriers, and combinatory treatments with immune checkpoint inhibitors. We also review recent advances and future directions in targeting pyroptosis to enhance tumor immunotherapy with immune checkpoint inhibitors, adoptive cell therapy, and tumor vaccines. This study suggested that targeting pyroptosis offers a promising avenue to amplify antitumor immune responses and surmount resistance to existing immunotherapies, potentially leading to more efficacious cancer treatments.

Regulation of the terminal complement cascade in adipose tissue for control of its volume, cellularity, and fibrosis

White adipose tissue (WAT) is a reservoir for various pathogens and their products, such as lipopolysaccharides. Therefore, it must be equipped with a defense mechanism connected with the activation of innate immunity. This explains the phenomenon that adipocytes express components of the classical and alternative complement pathways, which can be activated even in the absence of opportunistic pathogens. Terminal stages of the complement pathway are related to the production of membrane attack complexes and, thus, can cause lysis of pathogens, as well as autolysis of host adipocytes, contributing to the regulation of the cellularity in WAT. Complement-induced autolysis of adipocytes is counteracted by a number of cellular defense mechanisms. This versatility of activation and suppression processes enables a broad range of adaptability to physiological contexts, ranging from the development of hypertrophic WAT to lipodystrophy. Pathogen-induced activation of the complement pathway in WAT also induces a profibrotic phenotype. These processes may also be involved in the regulation of insulin resistance in adipocytes. This explains the dual immune/metabolic role of the complement pathway in WAT: the pathway is an integral part of the immune response but also potently involved in the control of volume and cellularity of WAT under both physiological and pathological conditions.

Targeting HPK1 inhibits neutrophil responses to mitigate post-stroke lung and cerebral injuries

Circulating neutrophils are responsible for poor neurological outcomes and have been implicated in respiratory morbidity after acute ischemic stroke (AIS). However, the molecular mechanisms regulating neutrophil responses and their pathological relevance in post-stroke complications remain unclear. In this study, we investigated the involvement of hematopoietic progenitor kinase 1 (HPK1) in neutrophil responses and mobilization, as well as subsequent lung and cerebral injuries following AIS. We found that lipopolysaccharide treatment triggered neutrophil activation in an HPK1-dependent manner. HPK1 enhanced intrinsic NF-κB/STAT3/p38-MAPK pathways and gasdermin D cleavage, leading to neutrophil hyperactivation. Following AIS, HPK1 promoted the mobilization of CXCR2high bone marrow neutrophils. HPK1 loss inhibited peripheral neutrophil hyperactivation, neutrophil infiltration, and aggregation of neutrophil extracellular traps, progressively alleviating systemic inflammation and impairments in mouse pulmonary and neurological functions. Furthermore, HPK1 pharmacological inhibition attenuated post-stroke pulmonary and neurological impairments in mice. Our findings revealed that HPK1 upregulates neutrophil mobilization and various responses, promoting post-stroke systemic inflammation and tissue injury. This study highlights HPK1 as a therapeutic target for improving pulmonary and neurological functions after AIS.

Non-coding RNAs modulate pyroptosis in diabetic cardiomyopathy: A comprehensive review

Diabetic cardiomyopathy (DCM) is a leading cause of heart failure (HF) among individuals with diabetes, presenting a significant medical challenge due to its complex pathophysiology and the lack of targeted therapies. Pyroptosis, a pro-inflammatory form of programmed cell death (PCD), is the predominant mode of cell death in the primary resident cells involved in DCM. It has been reported to be critical in DCM's onset, progression, and pathogenesis. Non-coding RNAs (ncRNAs), diverse transcripts lacking protein-coding potential, are essential for cellular physiology and the progression of various diseases. Increasing evidence indicates that ncRNAs are pivotal in the pathogenesis of DCM by regulating pyroptosis. This observation suggests that targeting the regulation of pyroptosis by ncRNAs may offer a novel therapeutic approach for DCM. However, a comprehensive review of this topic is currently lacking. Our objective is to elucidate the regulatory role of ncRNAs in pyroptosis associated with DCM and to elucidate the relationships among these factors. Additionally, we explored how ncRNAs influence pyroptosis and contribute to the pathophysiology of DCM. By doing so, we aim to identify new research targets for the clinical diagnosis and treatment of DCM.

AIM2 exacerbates hypoxic-ischemic brain damage in neonatal rats via promoting neuronal pyroptosis

BACKGROUND

Pyroptosis has been reported to play a pathogenic role in neonatal hypoxic-ischemic brain damage (HIBD). Absence in melanoma 2 (AIM2) is an inflammasome involved in pyroptosis.

OBJECTIVE

This study aimed to investigate the role of AIM2 in hypoxic-ischemia (HI)-induced pyroptosis and brain damage in a neonatal rat HIBD model.

METHODS

In vivo, we injected a lentivirus that overexpressed or knocked down AIM2 into the lateral ventricle of rats within 24 h after birth and prepared a 7-day Sprague Dawley (SD) rat HIBD model. In vitro, we transfected lentiviruses overexpressing or knocking down AIM2 into cultured primary neurons and established an oxygen/glucose deprivation/reoxygenation (OGD/R) model. 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to determine infarct size. Hematoxylin and eosin and Nissl staining were used to evaluate morphological changes in the damaged brain. Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays were used to determine cell viability and toxicity. Pyroptosis was observed using transmission electron microscopy.

RESULTS

AIM2 expression significantly increased in the HI-induced cortex of neonatal rats. Lentivirus-mediated overexpression of AIM2 significantly aggravates HI-induced brain injury and OGD/R-induced neuronal injury in vivo and in vitro. The lentivirus-mediated AIM2 knockdown significantly reversed these adverse effects. In addition, AIM2 overexpression increased HI-induced pyroptosis in neonatal rats in vivo and in vitro, whereas AIM2 knockdown suppressed HI-induced pyroptosis via the AIM2/Caspase-1/GSDMD pathway.

CONCLUSION

These findings show that the upregulation of AIM2 activates pyroptosis and plays a pathogenic role in neonatal HIBD.

Potential Impact of Climate Change-Induced Alterations on Pyroptotic Cell Death in Animal Cells: A Review

Climate change-induced alterations in temperature variation, ozone exposure, water salinity and acidification, and hypoxia might influence immunity and thus survival in diverse groups of animals from fish to mammals. Pyroptosis is a type of lytic pro-inflammatory programmed cell death, which participates in the innate immune response, and is involved in multiple diseases characterized by inflammation and cell death, mostly studied in human cells. Diverse extrinsic factors can induce pyroptosis, leading to the extracellular release of pro-inflammatory molecules such as IL-18. Climate change-related factors, either directly or indirectly, can also promote animal cell death via different regulated mechanisms, impacting organismal fitness. However, pyroptosis has been relatively less studied in this context compared to another cell death process, apoptosis. This review covers previous research pointing to the potential impact of climate change, through various abiotic stressors, on pyroptotic cell death in different animal cells in various contexts. It was proposed that temperature, ozone exposure, water salinity, water acidification and hypoxia have the potential to induce pyroptotic cell death in animal cells and promote inflammation, and that these pyroptotic events should be better understood to be able to mitigate the adverse effects of climate change on animal physiology and health. This is of high importance considering the increasing frequency, intensity and duration of climate-based changes in these environmental parameters, and the critical function of pyroptosis in immune responses of animals and in their predisposition to multiple diseases including cancer. Furthermore, the need for further mechanistic studies showing the more direct impact of climate change-induced environmental alterations on pyroptotic cell death in animals at the organismal level was highlighted. A complete picture of the association between climate change and pyroptosis in animals will be also highly valuable in terms of ecological and clinical applications, and it requires an interdisciplinary approach. SIGNIFICANCE: Climate change-induced alterations might influence animal physiology. Pyroptosis is a form of cell death with pro-inflammatory characteristics. Previous research suggests that temperature variation, ozone exposure, water salinity and acidification, and hypoxia might have the potential to contribute to pyroptotic cell death in certain cell types and contexts. Climate change-induced pyroptotic cell death should be better understood to be able to mitigate the adverse effects of climate change on animal health.

Amplifying Ca2+ overload by engineered biomaterials for synergistic cancer therapy

Ca2+ overload is one of the most widely causes of inducing apoptosis, pyroptosis, immunogenic cell death, autophagy, paraptosis, necroptosis, and calcification of tumor cells, and has become the most valuable therapeutic strategy in the field of cancer treatment. Nevertheless, several challenges remain in translating Ca2+ overload-mediated therapeutic strategies into clinical applications, such as the precise control of Ca2+ dynamics, specificity of Ca2+ homeostasis dysregulation, as well as comprehensive mechanisms of Ca2+ regulation. Given this, we comprehensively reviewed the Ca2+-driven intracellular signaling pathways and the application of Ca2+-based biomaterials (such as CaCO3-, CaP-, CaO2-, CaSi-, CaF2-, and CaH2-) in mediating cancer diagnosis, treatment, and immunotherapy. Meanwhile, the latest researches on Ca2+ overload-mediated therapeutic strategies, as well as those combined with multiple-model therapies in mediating cancer immunotherapy are further highlighted. More importantly, the critical challenges and the future prospects of the Ca2+ overload-mediated therapeutic strategies are also discussed. By consolidating recent findings and identifying future research directions, this review aimed to advance the field of oncology therapy and contribute to the development of more effective and targeted treatment modalities.

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.

Chemo-sensitive and chemo-resistant ovarian cancer cells show differences in cellular processes leading to pyroptotic cell death

Tumor immunology in ovarian cancer is not completely understood. Chemoresistance limits the success of available treatment options for patients with ovarian cancer. Pyroptosis, pro-inflammatory programmed cell death characterized by membrane pore formation by gasdermin proteins, is important for both immunogenicity and drug resistance. Here, we showed that estrogen increases GSDMC and GSDMD mRNA levels in chemo-sensitive ovarian cancer cells; but, not in chemo-resistant ovarian cancer cells in vitro. GSDMC or GSDMD overexpression increases cell viability in chemo-sensitive ovarian cancer cells; but, not in chemo-resistant ovarian cancer cells. Silencing of GSDMD in chemo-sensitive ovarian cancer cells and silencing of GSDMC in chemo-resistant ovarian cancer cells limit the effect of nigericin, a pyroptosis inducer, on cell viability. Inhibition of caspase-1, -4, -6 or -8 blocks nigericin-induced cell death (pyroptosis) in chemo-sensitive ovarian cancer cells; however, only the inhibition of caspase-1 blocks nigericin-induced cell death in chemo-resistant ovarian cancer cells, showing that caspases participating in pyroptosis might differ between ovarian cancer cells based on their chemo-sensitivity profiles. Treatment with disulfiram, a GSDMD pore formation inhibitor, decreases cell viability in both cell lines. Lastly, we found that in chemo-resistant ovarian cancer cell line, disulfiram and nigericin combination treatment decreases cell viability even more compared to only disulfiram or only nigericin treatment. Combined, our study points that ovarian cancer cells with different chemosensitivity profiles might have certain differences in pyroptotic cell death.

An epigenetic regulator synergizes with alphavirus-mediated gene therapy via biomimetic delivery for enhanced cancer therapy

Gene therapy is promising for treating genetic disorders, but faces challenges in treating cancer due to the intricate genetic and immunosuppressive landscape of this disease. Here, we describe a technology combining alphavirus-based gene therapy with an epigenetic regulator via pyroptosis and immune checkpoints to address these challenges. A filamentous actin-mimicking liposomal delivery system, with high fusion efficiency, was developed that encapsulates the Semliki Forest virus (pSFV) DNA vector to deliver p53 and PDL1 scFv DNA, bypassing traditional endocytic barriers to deliver genes with high efficiency via membrane fusion. To enhance this combined therapy, the DNA methyltransferase inhibitor decitabine (DAC) was used to increase Gasdermin E (GSDME) expression, converting apoptosis to pyroptosis. This approach kills apoptosis-resistant tumor cells, and also promotes T cell infiltration and activation, facilitating an anti-PDL1 therapy and the systemic antitumor immune response. This multifaceted therapeutic strategy combines gene therapy with epigenetic regulation to significantly improve immune checkpoint therapy (ICT) effectiveness, offering a robust potential as a transformative cancer treatment.

Role of ubiquitin-specific proteases in programmed cell death of breast cancer cells

Breast cancer (BC) is the most common malignant tumor and the leading cause of cancer-related deaths among women worldwide. Great progress has been recently achieved in controlling breast cancer; however, mortality from breast cancer remains a substantial challenge, and new treatment mechanisms are being actively sought. Programmed cell death (PCD) is associated with the progression and treatment of many types of human cancers. PCD can be divided into multiple pathways including autophagy, apoptosis, mitotic catastrophe, necroptosis, ferroptosis, pyroptosis, and anoikis. Ubiquitination is a post-translational modification process in which ubiquitin, a 76-amino acid protein, is coupled to the lysine residues of other proteins. Ubiquitination is involved in many physiological events and promotes cancer development and progression. This review elaborates the role of ubiquitin-specific protease (USP) in programmed cell death, which is common in breast cancer cells, and lays the foundation for tumor diagnosis and targeted therapy.

Microbial Photosynthetic Oxygenation and Radiotherapeutic Sensitization Enables Pyroptosis Induction for Combinatorial Cancer Therapy

Rectal cancer surgery is challenging due to the complex anatomy, making it difficult to achieve clear surgical margins. Radiotherapy (RT) plays a crucial role, especially in treating locally recurrent rectal cancer and preserving anal function. However, its effectiveness is often limited by tumor hypoxia, particularly prevalent in hypoxic regions near the bowel wall in colorectal cancer. Hypoxia contributes to both radiation resistance and apoptosis resistance, compromising RT outcomes. To overcome hypoxia-driven radiotherapy resistance, this work designs and engineers a radiotherapy-sensitizing bioplatform for efficient cancer RT. It combines lanthanum oxide nanoparticles (La2O3 NPs) with cyanobacteria, which produces oxygen through photosynthesis. This bioplatform uniquely reduces tumor hypoxia, enhances radiation deposition, and improves RT efficacy. La2O3 NPs further enhance reactive oxygen species (ROS) production induced by radiation, triggering pyroptosis via the ROS-NLRP3-GSDMD pathway, while RT amplifies pyroptosis through GSDME, circumventing tumor apoptosis resistance. The further integrated thermosensitive hydrogels ensure precise localization of the bioplatform, reducing systemic toxicity and improving therapeutic specificity. Compared to conventional therapies, this dual-action system addresses hypoxia, RT resistance, and apoptosis resistance more effectively. In vivo and in vitro hypoxia models validate its potent anti-tumor efficacy, offering valuable insights for refining clinical treatment paradigms.

FlexiPlasma Microcatheter-Embolic Material (FPM-EM) Platform: A Non-Inflammatory Pyroptosis Strategy for Precision Hepatocellular Carcinoma Therapy

Hepatocellular carcinoma (HCC) remains a global challenge, with conventional locoregional therapies like transarterial chemoembolization (TACE) lacking tumor specificity and promoting metastasis and inflammation. Cold atmospheric plasma (CAP) offers a tumor-selective ablation strategy but suffers from limited tissue penetration. To overcome this, the FlexiPlasma microcatheter (FPM) is developed, integrating flexible non-metallic microtubes and ring-shaped electrodes for precise CAP delivery to deep tumors. The optimized FPM-generated CAP eliminates cytotoxic UV and ozone while inducing tumor-specific pyroptosis via a ROS/Caspase-8/GSDMC pathway. Gasdermin-C (GSDMC) is highly expressed in liver tumors but absent in normal tissues, ensuring selective targeting with minimal inflammation. FPM is combined with embolic material (EM), PPP@CD hydrogel, enhancing injectability, tumor embolization, and sustained drug release. This FPM-EM strategy potentiates antitumor immunity, particularly CD4+ and CD8+ T-cell responses. These findings establish FPM-EM as a safe, effective, and minimally invasive therapy for HCC, revealing a non-inflammatory pyroptosis mechanism and broadening the potential of CAP-based cancer treatments. The FPM-EM combination offers promising new therapeutic options for HCC, addressing the limitations of TACE. Furthermore, the FPM-EM platform can be extended to the interventional therapy of other tumors and adapted to incorporate various drugs and nano-/micro-materials, highlighting the strong potential for future clinical translation.

Adiponectin alleviates inflammatory response in metabolic dysfunction-associated steatohepatitis by inhibiting NLRP3 inflammasome-mediated hepatocyte pyroptosis

BACKGROUND

Activation of NLRP3 (NOD-, LRR- and pyrin domain-containing protein 3) inflammasomes induced by pyroptosis is crucial in metabolic dysfunction-associated steatohepatitis (MASH) progression. Adiponectin possesses an anti-inflammatory role in various liver diseases. This study aimed to evaluate the effects of adiponectin on MASH.

METHODS

Adiponectin-mediated anti-inflammatory mechanisms, effects on pyroptosis-related proteins, and activation of NLRP3 inflammasomes were investigated using methionine-choline-deficient (MCD)-induced MASH murine model and in vitro models. The degree of MASH inflammation in liver tissue of C57BL/6J mice was assessed using histopathology. Enzyme-linked immunosorbent assay was performed to measure levels of inflammatory factors [interleukin-18 (IL-18), IL-1β, and tumor necrosis factor-α (TNF-α)] in mice serum and culture medium. Western blot and quantitative polymerase chain reaction were performed to analyze the expression of pyroptosis-related genes and proteins in liver tissues of mouse model and in vitro models. Macrophage recruitment in vitro was evaluated using co-culture of upper and lower chambers.

RESULTS

MASH developed in MCD diet mice [metabolic dysfunction-associated steatotic liver disease (MASLD) activity score = 6] but not in methionine-choline-sufficient (MCS) diet mice (MASLD activity score = 3). Compared to MCS-fed mice, MCD-fed mice showed increased serum levels of aspartate aminotransferase, IL-18, IL-1β, and TNF-α and higher MASLD activity score (P < 0.001). Adiponectin inhibited these increases (P < 0.05) and suppressed mRNA and protein levels of NLRP3, gasdermin-D (GSDMD), and GSDMD-N in liver tissues (P < 0.05). In vitro, lipopolysaccharide (LPS)/palmitic acid (PA) increased the levels of IL-18, IL-1β, and TNF-α, mRNA expressions of CASP1 and GSDMD, and production of CASP1, NLRP3, GSDMD, and GSDMD-N (P < 0.01). Adiponectin reduced the levels of these inflammatory factors and downregulated the mRNA expression and protein generation of pyroptosis-related markers (P < 0.05). HepG2 cells pretreated with LPS/PA recruited more J774A.1 cells (P < 0.001) and increased inflammatory factor secretion by J774A.1 cells (P < 0.001). Adiponectin inhibited this recruitment and reduced inflammatory factor secretion (P < 0.001).

CONCLUSIONS

Adiponectin inhibits hepatocyte pyroptosis by reducing the production and activation of NLRP3 inflammasomes, CASP1, and GSDMD, thus improving the inflammatory response in MASH and possibly delaying or reversing MASLD progression.

Glutathion peroxidase 4 (GPX4) and Ribosomal Protein L40 (RPL40) participate in arsenic induced progression of renal cell carcinoma by regulating the NLRP3 mediated classic pyroptosis pathway

Epidemiological studies have demonstrated that long-term exposure to high‑arsenic water increases the risk of kidney cancer. Kidney dysfunction can lead to the accumulation of metabolic waste and chronic inflammation, with the latter being a significant factor in tumor development. Therefore, it is crucial to investigate how environmental arsenic exposure affects renal function and inflammation, as well as its potential influence on the progression of renal carcinoma. Additionally, pyroptosis plays an essential role in immune responses and the maintenance of cellular homeostasis. However, the role and mechanisms of pyroptosis in arsenic-induced kidney cancer progression remain unexplored. Our findings indicated that low-dose arsenic exposure reduces pyroptosis and promotes abnormal proliferation of renal tubular epithelial cells, while high-dose exposure enhances pyroptosis and damages renal tissue structure in mouse models. Mechanistically, in vitro studies confirmed that low-dose arsenic exposure promotes the progression of renal cell carcinoma by downregulating NLRP3 and inhibiting pyroptosis, whereas high-dose exposure has the opposite effect. Proteomics analysis identified GPX4 and RPL40 as key proteins mediating pyroptosis induced by low and high doses of arsenic, respectively. Furthermore, GPX4 and RPL40 were shown to regulate the malignant progression of renal cell carcinoma through their effects on NLRP3-mediated pyroptosis. This study reveals that arsenic exposure induces pyroptosis via NLRP3, leading to renal injury and influencing the malignant progression of renal cancer. Notably, GPX4 and RPL40 regulate this progression under low and high-dose arsenic exposure, respectively.

Mitophagy in perioperative neurocognitive disorder: mechanisms and therapeutic strategies

Perioperative neurocognitive disorder (PND) is a common neurological complication after surgery/anesthesia in elderly patients that affect postoperative outcome and long-term quality of life, which increases the cost of family and social resources. The pathological mechanism of PND is complex and not fully understood, and the methods of prevention and treatment of PND are very limited, so it is particularly important to analyze the mechanism of PND. Research indicates that mitochondrial dysfunction is pivotal in the initiation and progression of PND, although the precise mechanisms remain elusive and could involve disrupted mitophagy. We reviewed recent studies on the link between mitophagy and PND, highlighting the role of key proteins in abnormal mitophagy and discussing therapeutic strategies aimed at mitophagy regulation. This provides insights into the mechanisms underlying PND and potential therapeutic targets.

Unlocking the Power of Photothermal Agents: A Universal Platform for Smart Immune NIR-Agonists for Precise Cancer Therapy

Selective ablation of tumor cells allows safe eradication, thereby minimizing off-target damage, while specifically inducing immunogenic cell death (ICD) rather than commonly non-immunogenic apoptosis of tumor cells enables activation of anti-tumor immune response against residual cancer cells, including metastatic lesions. Herein, we present a general strategy leveraging a novel photothermal agent (PTA) that concomitantly enables precise tumor killing and activation of anti-tumor immunity. The unique PTA scaffold exhibits unexpected inherent endoplasmic reticulum (ER)-targeting capability and potent near-infrared (NIR) photothermal activity, inducing NIR-controlled immunogenic pyroptosis in various tumor cell lines via targeting ER stress in an oxygen-independent manner. Moreover, both ER-targeting and NIR-activity of our scaffold can be modulated on demand by chemical caging/uncaging, allowing quick activation with diverse biological and bioorthogonal molecular triggers. The potency of this universal platform is demonstrated via its application to develop a membrane protein-activatable NIR-agonist that selectively activates ICD in tumor sites while priming anti-tumor immunity, minimizing off-target effects and enhancing efficacy against mouse breast tumors. This versatile approach could lead to customization of various personalized and effective immune NIR-agonists for specific photoimmunotherapy applicable to diverse solid tumors.

Regulation of pyroptosis by natural products in ulcerative colitis: mechanisms and therapeutic potential

Ulcerative colitis (UC), a chronic inflammatory bowel disease, is driven by dysregulated immune responses and persistent intestinal inflammation. Pyroptosis, a caspase/gasdermin-mediated inflammatory cell death that exacerbates mucosal damage through excessive cytokine release and epithelial barrier disruption. Although pyroptosis is considered to be a key mechanism in the pathogenesis of UC, the systematic assessment of the role of natural products in targeting the pyroptosis pathway remains a critical research gap. The purpose of this review is to investigate the regulatory effects of natural products on pyroptosis in UC and elucidate the mechanisms of action and potential therapeutic effects. Key findings highlight polyphenols (e.g., resveratrol), flavonoids (e.g., Quercetin), and terpenoids as promising agents that inhibit NLRP3 inflammasome activation, suppress gasdermin D cleavage, and restore barrier integrity, thereby reducing pro-inflammatory cytokine release in preclinical UC models. Current evidence shows enhanced efficacy and safety when these compounds are combined with standard therapies, but clinical translation requires overcoming three key barriers: limited human trial data, uncharacterized polypharmacology, and suboptimal pharmacokinetics needing formulation refinement. Future research should prioritize standardized animal-to-human translational models, mechanistic studies on synergistic pathways, and rigorous clinical validation to harness the full potential of natural products in pyroptosis-targeted UC therapies.

Teleost GSDMEc regulates GSDMEa-mediated pyroptosis

INTRODUCTION

Gasdermin (GSDM) is a family of proteins that execute pyroptosis after being activated by caspase (CASP) cleavage. Mammals possess five GSDM members (A - E) with pyroptotic ability. Teleosts possess only one pyroptotic GSDM, GSDME, that exists in three orthologs, GSDMEa, b, and c. GSDMEa and GSDMEb are known to induce pyroptosis, but the function of GSDMEc is unknown.

OBJECTIVES

The present study aimed to elucidate the function of teleost GSDMEc and examine the interplay among teleost GSDME orthologs by using snakehead Channa argus as a representative species.

METHODS

Pyroptosis was assessed via microscopy and biochemical assays. GSDME cleavage, oligomerization, and membrane translocation were examined via immunoblotting. The interactions of GSDME products were examined using confocal microscopy and co-immunoprecipitation. GSDME knockdown in fish and in vivo bacterial infection were performed.

RESULTS

C. argus possessed three GSDME variants (CaGSDMEa, CaGSDMEc1, and CaGSDMEc2). CaGSDMEa was cleaved by C. argus CASP (CaCASP) 1/8 to produce an N-terminal fragment (NT), NT261, that induced pyroptosis. CaGSDMEc1 and CaGSDMEc2 were also cleaved by CaCASP1/8, but the resulting NTs, NT123 and NT108, respectively, were unable to induce pyroptosis. However, both NT123 and NT108 could bind and promote the pyroptotic activity of NT261 by facilitating NT261 oligomerization and membrane translocation. The interaction between NT261 and NT123/NT108 depended on a positively charged motif that is conserved in the metazoan GSDME and is essential to the membrane localization of NT123 and the pyroptotic activity of NT261. Bacterial infection induced CaGSDMEa/CaCASP8 activation and CaGSDMEc1/c2 cleavage in snakehead cells, resulting in pyroptosis, IL-1β/18 maturation cleavage, and extracellular DNA-net formation. CaGSDMEa/c1 knockdown significantly increased bacterial dissemination in fish tissues and reduced fish survival.

CONCLUSIONS

Our results revealed the functions and interactive mechanism of teleost GSDME orthologs, and provided new insights into the regulation of pyroptosis in lower vertebrates.

Controlling pyroptosis through post-translational modifications of gasdermin D

Pyroptosis, a lytic and programmed cell death pathway, is mediated by gasdermins (GSDMs), with GSDMD playing an important role in innate immunity and pathology. Upon activation, GSDMD is cleaved to release the active N-terminal fragment that oligomerizes into membrane pores, which promote pyroptosis and cytokine secretion, leading to inflammation. Emerging evidence indicates that post-translational modification (PTM) is an important regulatory mechanism of GSDMD activity. This review explores how PTMs, aside from proteolytic cleavage, control GSDMD activity and link biological contexts to pyroptosis in innate immunity and inflammation, which could inform future studies and therapeutic solutions for treating inflammatory conditions.

Modeling Necroptotic and Pyroptotic Signaling in Saccharomyces cerevisiae

The yeast Saccharomyces cerevisiae is the paradigm of a eukaryotic model organism. In virtue of a substantial degree of functional conservation, it has been extensively exploited to understand multiple aspects of the genetic, molecular, and cellular biology of human disease. Many aspects of cell signaling in cancer, aging, or metabolic diseases have been tackled in yeast. Here, we review the strategies undertaken throughout the years for the development of humanized yeast models to study regulated cell death (RCD) pathways in general, and specifically, those related to innate immunity and inflammation, with an emphasis on pyroptosis and necroptosis. Such pathways involve the assembly of distinct modular signaling complexes such as the inflammasome and the necrosome. Like other supramolecular organizing centers (SMOCs), such intricate molecular arrangements trigger the activity of enzymes, like caspases or protein kinases, culminating in the activation of lytic pore-forming final effectors, respectively, Gasdermin D (GSDMD) in pyroptosis and MLKL in necroptosis. Even though pathways related to those governing innate immunity and inflammation in mammals are missing in fungi, the heterologous expression of their components in the S. cerevisiae model provides a "cellular test tube" to readily study their properties and interactions, thus constituting a valuable tool for finding novel therapies.

Multiwalled carbon nanotubes activate the NLRP3 inflammasome-dependent pyroptosis in macrophages

Macrophages are major innate immune cells for the clearance of inhaled nanoparticles but may undergo cell death upon phagocytosis of certain nanoparticles due to their resistance to lysosomal degradation and high toxicity to the cell. Here we investigated the pyroptotic effect of exposure to fibrogenic multiwalled carbon nanotubes (MWCNTs) on macrophages, an inflammatory form of cell death. We first evaluated MWCNT-induced cell death in M1 and M2 macrophages that mediate the temporal inflammatory response to MWCNTs in mammalian lungs. Macrophages were differentiated from human monocytic THP-1 cells, followed by polarization to M1 or M2 cells. MWCNTs caused concentration- and time-dependent cytotoxicity in M1 and, to a lesser extent, M2 cells. Carbon black, an amorphous carbonous material control for CNTs, did not cause apparent toxicity in the cells. MWCNTs increased the production and secretion of IL-1β, accompanied by activation of caspase-1, in M1, but not M2, cells. Moreover, MWCNTs induced the formation of apoptosis-associated speck-like protein containing a C-terminal caspase recruitment domain specks and the release of cathepsin B in M1 cells, revealing activation of the nucleotide-binding, oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) inflammasome via lysosomal damage. MWCNTs induced the cleavage of gasdermin D (GSDMD) to form the 31 kDa N-terminal fragment (GSDMD-N), the pore-forming peptide causing pyroptotic cell death. Increased IL-1β release was completely suppressed by AC-YVAD-CMK (a caspase-1 inhibitor), MCC-950 (an NLRP3 inflammasome inhibitor), or CA-074 Me (a cathepsin B inhibitor), alongside the blockage of MWCNT-induced cleavage of GSDMD. The study demonstrates that MWCNTs trigger pyroptosis in M1 macrophages and boost sterile inflammation by activating the NLRP3 inflammasome pathway. SIGNIFICANCE STATEMENT: The nucleotide-binding, oligomerization domain-like receptor family pyrin domain containing 3 inflammasome mediates the inflammatory response to fibrogenic nanoparticles in the lung via multiple means. The current study uncovers the induction of pyroptotic death of macrophages as a major means of nanotoxicity and sterile inflammation via the nucleotide-binding, oligomerization domain-like receptor family pyrin domain containing 3 pathway by nanoparticles.

Tandem-controlled lysosomal assembly of nanofibres induces pyroptosis for cancer immunotherapy

Pyroptosis has emerged as a promising approach for cancer immunotherapy. However, current pyroptosis inducers lack specificity for cancer cells and have a weak antitumour immune response. Here we report a tumour-specific nanoparticle (NP-NH-D5) that activates pyroptosis by disrupting lysosomes for cancer immunotherapy. NP-NH-D5 undergoes negative-to-positive charge reversal and nanoparticle-to-nanofibre transformation within tumour cell lysosomes through tandem response to extracellular matrix metallopeptidase-2 and intracellular reducing agents. The as-formed non-peptide nanofibres efficiently break the lysosomes and trigger gasdermin-D-mediated pyroptosis, leading to strong immunogenic cell death and alleviation of the immunosuppressive tumour microenvironment. In vivo, NP-NH-D5 inhibits orthotopic 4T1 breast tumours, prevents metastasis and recurrence, and prolongs survival without systemic side effects. Furthermore, it greatly enhances the effectiveness of PD-L1 antibody immunotherapy in the 4T1 late-stage lung metastasis and aggressive orthotopic Pan02 pancreatic tumour models. Our research may open pathways for developing stimuli-responsive pyroptosis inducers for precise cancer immunotherapy.

Gasdermin D mutation protects against renal ischemia reperfusion injury

Pyroptosis, the most inflammatory form of cell death, is dependent on membrane pore formation governed by the assembly of cleaved Gasdermin D (GSDMD). We hypothesized that regulated necrosis pathways are crucial in the pathophysiology of acute kidney injury (AKI). Mice with an isoleucine-to-asparagine loss-of-function mutation in the Gasdermin D gene (GSDMDI105N/I105N) generated by ethylnitrosourea-mutagenesis were subjected to bilateral renal ischemia-reperfusion injury (IRI) with bio-molecular readouts performed at 24 h. IRI was also performed in mice pretreated with disulfiram. Whole-body irradiation followed by syngeneic bone marrow transplantation generated chimeric mice prior to IRI. Mice homozygous for the GSDMD I105N mutation were protected from IRI, demonstrating lower serum creatinine and reduced histological injury, as well as decreased pro-inflammatory cytokine expression and oxidative stress. Chimeric mice showed that this protection was predominantly governed by mutations in the parenchymal tissue, with a potential contribution from the hematopoietic compartment. Pharmacological inhibition of GSDMD pore formation using disulfiram protected against IRI. Manipulation of GSDMD is an attractive target to mitigate inflammation and cellular death following AKI.

Functional Materials Targeted Regulation of Gasdermins: From Fundamentals to Functionalities and Applications

Targeted regulation of pyroptosis to modulate the immune landscape has emerged as a novel design strategy for cancer immunotherapy and anti-inflammatory therapy. However, pyroptosis acts as a double-edged sword, making it important to optimize the design strategies of functional materials to appropriately activate pyroptosis for effective disease treatment. This paper summarizes and discusses the structure, pore formation, and molecular mechanisms of "executor" Gasdermins, as well as the events preceding and following these processes. Subsequently, the focus is on reviewing functional materials that directly regulate Gasdermin pore formation to target pyroptosis and those that indirectly regulate the events before and after Gasdermin pore formation to control pyroptosis activity. Finally, the advantages, disadvantages, and future prospects of designing such functional materials are provided, aiming to facilitate the precise design, pharmacological investigation, and clinical translation of pyroptosis-related functional materials.

SNS‑032 combined with decitabine induces caspase‑3/gasdermin E‑dependent pyroptosis in breast cancer cells

SNS-032 is a synthetic compound that specifically inhibits cyclin-dependent kinases 2, 7 and 9. Its primary anticancer activity involves cell cycle arrest, which prevents tumor cell growth. However, there are limited reports on whether SNS-032 induces pyroptosis, a novel inflammation-mediated programmed cell death pathway in breast cancer (BC). The present study demonstrated that SNS-032 treatment decreased cell viability by inducing pyroptosis in BC cells. Typical morphological indications of pyroptosis were observed, including cell swelling and destruction of cell membrane integrity, leading the release of adenosine 5'-triphosphate and lactate dehydrogenase. Furthermore, the expression of caspase-3, the N terminus of gasdermin E (GSDME) and B-cell lymphoma-2 (BCL-2)-associated X protein increased, whereas expression of BCL-2 decreased. In addition, Z-DEVD-FMK, a specific caspase-3 inhibitor, markedly alleviated pyroptosis triggered by SNS-032. These findings suggested that SNS-032 induced caspase-3/GSDME-dependent pyroptosis. Furthermore, the present study demonstrated that decitabine (DAC), a DNA methyltransferase inhibitor, upregulated the expression of GSDME protein and enhanced SNS-032-induced caspase-3/GSDME-dependent pyroptosis in BC cells. In conclusion, these results suggest that caspase-3/GSDME-induced pyroptosis can be facilitated by SNS-032 treatment in BC cells, and DAC has the potential to enhance SNS-032-induced pyroptosis by increasing GSDME expression. This mechanistic insight indicates that SNS-032 is a promising therapeutic agent for BC treatment.

Electroacupuncture delays the progression of juvenile collagen-induced arthritis via regulation NLRP3/ NF-κB signaling pathway -mediated pyroptosis and its influence on autophagy

BACKGROUND

Juvenile idiopathic arthritis (JIA) can lead to synovial inflammation. JIA is a chronic autoimmune inflammatory condition that primarily affects children. It is recognized as the most prevalent form of arthritis in the pediatric population and is associated with significant impairment and disability. Electroacupuncture (EA) effectively treats various synovium-related conditions, including symptoms of synovial inflammation, in both human and animal models. However, the specific mechanism by which EA protects against JIA remains unclear. Therefore, we conducted a comprehensive study to investigate the protective mechanisms of EA in a rat model. We aimed to examine the impact of EA on pathological changes in synovial tissue of juvenile collagen-induced arthritis (CIA) rats.

METHODS

The CIA model was established using Sprague‒Dawley (SD) rats aged 2-3 weeks. In this study, we investigated the potential role of EA on JIA by regulating the NLRP3-NF-κB axis in juvenile CIA rats and its influence on autophagy. To verify the effect of EA on juvenile CIA, the expression of NLRP3 was overexpressed by an adeno-associated virus injected into the knee joint of the CIA rats.

RESULTS

In this study, we observed that NLRP3 plays an important role in developing juvenile CIA and that NLRP3 overexpression exacerbates inflammation and increases synovium inflammation. We also demonstrated that the expression of NLRP3 was increased in synovial tissue, and NLRP3 could upregulate the NF-κB signal pathway and influence inflammation. Moreover, we also found increases in the expression of NLRP3 by impairing autophagy capacity and activation of the pyroptosis pathway in the synovium of the juvenile CIA rats.

CONCLUSION

Moreover, we also discovered that EA decreased the expression of NLRP3 by restoring the impaired autophagy capacity and inhibiting the NLRP3-NF-κB axis, thereby delaying the progression of juvenile CIA. These results showed that EA is effective in inhibiting inflammation and synovial degeneration and alleviating the progression of juvenile CIA. As a result, our results provide new insight into the mechanism by which EA delays the development of juvenile CIA, offering a novel therapeutic regimen for JIA. This trial was registered with ClinicalTrials.gov, number NCT10203935. Registered October 07, 2023. Key Points • NLRP3 plays a critical role in juvenile collagen-induced arthritis (CIA), with its overexpression linked to increased inflammation in synovial tissue. • Electroacupuncture (EA) reduces NLRP3 expression and inhibits the NLRP3-NF-κB axis, mitigating inflammatory responses and delaying juvenile CIA progression. • EA restores impaired autophagy in juvenile CIA rats, promoting cellular health and inflammation management. • EA alleviates synovial degeneration, improving joint health and function in juvenile CIA models.

Unravelling the Role of PANoptosis in Liver Diseases: Mechanisms and Therapeutic Implications

PANoptosis is a multimodal form of cell death that involves inflammatory, apoptotic, and necroptotic pathways, playing a key role in the development of liver diseases. This article first outlines the definition and characteristics of PANoptosis, and then explores its mechanisms of action in different types of liver diseases, including acute liver injury, liver failure, metabolic dysfunction-associated fatty liver disease, and hepatocellular carcinoma. Furthermore, this article analyses the molecular regulatory network of PANoptosis and potential therapeutic targets. Finally, this article summarises the current research on PANoptosis in liver diseases and future research directions, and it reviews the role of the emerging cell death mechanism of PANoptosis in liver diseases.

The novel BCL-2/BCL-XL inhibitor APG-1252-mediated cleavage of GSDME enhances the antitumor efficacy of HER2-targeted therapy in HER2-positive gastric cancer

HER2-positive gastric cancer has a poor prognosis, with a high incidence of drug resistance and a lack of effective treatments for drug-resistant patients. The exploration of the mechanism of resistance to HER2-targeted therapy in HER2-positive gastric cancer and the identification of effective strategies to reverse it are urgently needed. In this study, we found that HER2-targeted agents upregulated the expression of GSDME and that the overexpression of GSDME attenuated the sensitivity of HER2-targeted agents. Furthermore, we observed that the BCL-2/BCL-XL inhibitor APG-1252 plus lapatinib promoted GSDME-mediated pyroptosis and exhibited remarkable antitumor activity both in vitro and in vivo. Mechanistically, APG-1252 combined with lapatinib synergistically induced GSDME-mediated pyroptosis in HER2-positive gastric cancer by activating caspase-dependent pathways and blocking the phospho-AKT/GSK-3β/MCL-1 signaling pathway. Our data indicated that the combination of lapatinib and APG-1252 had a synergistic antitumor effect on HER2-positive gastric cancer through the induction of caspase-3/GSDME-mediated apoptosis and pyroptosis.

Atrial cardiomyocyte-restricted cleavage of gasdermin D promotes atrial arrhythmogenesis

BACKGROUND AND AIMS

Enhanced inflammatory signalling causally contributes to atrial fibrillation (AF) development. Gasdermin D (GSDMD) is an important downstream effector of several inflammasome pathways. However, the role of GSDMD, particularly the cleaved N-terminal (NT)-GSDMD, in non-immune cells remains elusive. This study aimed to elucidate the function of NT-GSDMD in atrial cardiomyocytes (ACMs) and determine its contribution to atrial arrhythmogenesis.

METHODS

Human atrial appendages were used to assess the protein levels and localization. A modified adeno-associated virus 9 was employed to establish ACM-restricted overexpression of NT-GSDMD in mice.

RESULTS

The cleavage of GSDMD was enhanced in ACMs of AF patients. Atrial cardiomyocyte-restricted overexpression of NT-GSDMD in mice increased susceptibility to pacing-induced AF. The NT-GSDMD pore formation facilitated interleukin-1β secretion from ACMs, promoting macrophage infiltration, while up-regulating 'endosomal sorting complexes required for transport'-mediated membrane-repair mechanisms, which prevented inflammatory cell death (pyroptosis) in ACMs. Up-regulated NT-GSDMD directly targeted mitochondria, increasing mitochondrial reactive oxygen species (ROS) generation, which triggered proarrhythmic calcium-release events. The NT-GSDMD-induced arrhythmogenesis was mitigated by the mitochondrial-specific antioxidant MitoTEMPO. A mutant NT-GSDMD lacking pore-formation capability failed to cause mitochondrial dysfunction or induce atrial arrhythmia. Genetic ablation of Gsdmd prevented spontaneous AF development in a mouse model.

CONCLUSIONS

These findings establish a unique pyroptosis-independent role of NT-GSDMD in ACMs and arrhythmogenesis, which involves ROS-driven mitochondrial dysfunction. Mitochondrial-targeted therapy, either by reducing ROS production or inhibition of GSDMD, prevents AF inducibility, positioning GSDMD as a novel therapeutic target for AF prevention.

Role of gasdermins in chronic kidney disease

Gasdermins (GSDMs), functioning as membrane perforating proteins, can be activated by canonical inflammasomes, noncanonical inflammasomes, as well as non-inflammasomes, leading to cell pyroptosis and the subsequent release of inflammatory mediators. Increasing evidence has implicated that GSDMs are associated with chronic kidney disease (CKD), including diabetes nephropathy, lupus nephritis, obstructive nephropathy, and crystalline nephropathy. This review centers on the role of GSDMs-mediated pyroptosis in the pathogenesis of CKD, providing novel ideas for enhancing the prognosis and therapeutic strategies of CKD.

Pyroptosis for osteoarthritis treatment: insights into cellular and molecular interactions inflammatory

Osteoarthritis (OA) is a widely prevalent chronic degenerative disease often associated with significant pain and disability. It is characterized by the deterioration of cartilage and the extracellular matrix (ECM), synovial inflammation, and subchondral bone remodeling. Recent studies have highlighted pyroptosis-a form of programmed cell death triggered by the inflammasome-as a key factor in sustaining chronic inflammation. Central to this process are the inflammatory cytokines interleukin-1β (IL-1β) and interleukin-18 (IL-18), which play crucial roles mediating intra-articular pyroptosis through the NOD-like receptor protein 3 (NLRP3) inflammasome. This paper investigates the role of the pyroptosis pathway in perpetuating chronic inflammatory diseases and its linkage with OA. Furthermore, it explores the mechanisms of pyroptosis, mediated by nuclear factor κB (NF-κB), the purinergic receptor P2X ligand-gated ion channel 7 (P2X7R), adenosine monophosphate (AMP)-activated protein kinase (AMPK), and hypoxia-inducible factor-1α (HIF-1α). Additionally, it examines the interactions among various cellular components in the context of OA. These insights indicate that targeting the regulation of pyroptosis presents a promising therapeutic approach for the prevention and treatment of OA, offering valuable theoretical perspectives for its effective management.

Structural basis for the pore-forming activity of a complement-like toxin

Pore-forming proteins comprise a highly diverse group of proteins exemplified by the membrane attack complex/perforin (MACPF), cholesterol-dependent cytolysin (CDC), and gasdermin superfamilies, which all form gigantic pores (>150 angstroms). A recently found family of pore-forming toxins, called CDC-like proteins (CDCLs), are wide-spread in gut microbes and are a prevalent means of antibacterial antagonism. However, the structural aspects of how CDCLs assemble a pore remain a mystery. Here, we report the crystal structure of a proteolytically activated CDCL and cryo-electron microscopy structures of a prepore-like intermediate and a transmembrane pore providing detailed snapshots across the entire pore-forming pathway. These studies reveal a sophisticated array of regulatory features to ensure productive pore formation, and, thus, CDCLs straddle the MACPF, CDC, and gasdermin lineages of the giant pore superfamilies.

LXR agonists induces GSDME-mediated pyroptosis in tumors through alters the integrity of the MOM to activates Caspase-4/APAF-1 pyroptosome

Liver X receptors (LXRs) play a key role in cholesterol transport, glucose metabolism and the tumorigenesis. LXR ligands can inhibit tumor growth through several mechanisms, such as suppressing tumor cell proliferation and migration, and inducing tumor cell death. Among them, induction of tumor cell death is one of the main mechanisms by which LXR ligands inhibit tumor growth; but how exactly LXR ligands cause cell death is still unclear. In this study, we found that LXR agonists can induce nonclassical pyroptosis in various cancer cells. Further study we found that Caspase-3-mediated GSDME cleavage is involved in LXR agonist-induced pyroptosis. Mechanically, LXR agonists firstly induce ER stress in tumor cells, then the ER stress induced by LXR agonists alters the integrity of the mitochondrial outer membrane (MOM) through the NOXA and BAX/BAK. Subsequently, mitochondrial permeability transition activates Caspase-4/APAF-1 pyroptosome to activate GSDME-dependent pyroptosis. Finally, we also found that LXR agonists induced GSDME-dependent pyroptosis in mouse cells. Our results demonstrated that LXR agonists can induce nonclassical GSDME-dependent pyroptosis in cancer cells by inducing ER stress, which alters the integrity of MOM to activate Caspase-4/APAF-1 pyroptosome.

Cell death in acute lung injury: caspase-regulated apoptosis, pyroptosis, necroptosis, and PANoptosis

There has been abundant research on the variety of programmed cell death pathways. Apoptosis, pyroptosis, and necroptosis under the action of the caspase family are essential for the innate immune response. Caspases are classified into inflammatory caspase-1/4/5/11, apoptotic caspase-3/6/7, and caspase-2/8/9/10. Although necroptosis is not caspase-dependent to transmit cell death signals, it can cross-link with pyroptosis and apoptosis signals under the regulation of caspase-8. An increasing number of studies have reiterated the involvement of the caspase family in acute lung injuries caused by bacterial and viral infections, blood transfusion, and ventilation, which is influenced by noxious stimuli that activate or inhibit caspase engagement pathways, leading to subsequent lung injury. This article reviews the role of caspases implicated in diverse programmed cell death mechanisms in acute lung injury and the status of research on relevant inhibitors against essential target proteins of the described cell death mechanisms. The findings of this review may help in delineating novel therapeutic targets for acute lung injury.

Versatility of gasdermin D beyond pyroptosis

Gasdermin D (GSDMD) has garnered significant attention primarily for the pore-forming role of its p30 N-terminal fragment (NT-p30) generated during pyroptosis, a proinflammatory form of cell death. However, emerging evidence suggests that the formation of GSDMD-NT pores is reversible, and the activation of GSDMD does not necessarily lead to pyroptosis. Instead, this process may take part either in other forms of cell death, or in various state changes of living cells, including (i) inflammation regulation, (ii) endolysosomal pathway rewiring, (iii) granule exocytosis, (iv) type II immunity, (v) food tolerance maintenance, and (vi) temporary permeability alteration. This review explores the latest insights into the involvement of GSDMD in cell death and homeostasis maintenance, aiming to underscore the pleiotropic nature of GSDMD.

The Role of the Tumor Microenvironment (TME) in Advancing Cancer Therapies: Immune System Interactions, Tumor-Infiltrating Lymphocytes (TILs), and the Role of Exosomes and Inflammasomes

Understanding how different contributors within the tumor microenvironment (TME) function and communicate is essential for effective cancer detection and treatment. The TME encompasses all the surroundings of a tumor such as blood vessels, fibroblasts, immune cells, signaling molecules, exosomes, and the extracellular matrix (ECM). Subsequently, effective cancer therapy relies on addressing TME alterations, known drivers of tumor progression, immune evasion, and metastasis. Immune cells and other cell types act differently under cancerous conditions, either driving or hindering cancer progression. For instance, tumor-infiltrating lymphocytes (TILs) include lymphocytes of B and T cell types that can invade malignancies, bringing in and enhancing the ability of immune system to recognize and destroy cancer cells. Therefore, TILs display a promising approach to tackling the TME alterations and have the capability to significantly hinder cancer progression. Similarly, exosomes and inflammasomes exhibit a dual effect, resulting in either tumor progression or inhibition depending on the origin of exosomes, type of inflammasome and tumor. This review will explore how cells function in the presence of a tumor, the communication between cancer cells and immune cells, and the role of TILs, exosomes and inflammasomes within the TME. The efforts in this review are aimed at garnering interest in safer and durable therapies for cancer, in addition to providing a promising avenue for advancing cancer therapy and consequently improving survival rates.

New Insights on the Potential Role of Pyroptosis in Parkinson's Neuropathology and Therapeutic Targeting of NLRP3 Inflammasome with Recent Advances in Nanoparticle-Based miRNA Therapeutics

Parkinson's disease (PD) is a widespread neurodegenerative disorder characterized by the gradual degeneration of dopaminergic neurons in the substantia nigra pars compacta (SNc). This review aims to summarize the recent advancements in the pathophysiological mechanisms of pyroptosis, mediated by NLRP3 inflammasome, in advancing PD and the anti-pyroptotic agents that target NLRP3 inflammatory pathways and miRNA. PD pathophysiology is primarily linked to the aggregation of α-synuclein, the overproduction of reactive oxygen species (ROS), and the development of neuroinflammation due to microglial activation. Prior research indicated that a significant quantity of microglia is activated in both PD patients and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse models, triggering neuroinflammation and resulting in a cascade of cellular death. Microglia possess an inflammatory complex pathway termed the nucleotide-binding oligomerization domain-, leucine-rich repeat, and pyrin domain-containing 3 (NLRP3) inflammasome. Activation of the NLRP-3 inflammasome results in innate cytokines maturation, including IL-18 and IL-1β, which initiates the neuroinflammatory signal and induces a type of inflammatory cell death known as pyroptosis. Upon neuronal damage, intracellular levels of damage-associated molecular patterns (DAMPs), including reactive oxygen species (ROS), would build. DAMPs induce unregulated cell death and subsequent release of oxidative intermediates and pro-inflammatory cytokines, leading to the progression of PD. Thus, targeting of neuroinflammation using antipyroptotic medications can be efficiently achieved by blocking NLRP3 and obstructing IL-1β signaling and release. Furthermore, many research studies showed that miRNAs have been identified as regulators of the NLRP3 inflammasome and Nrf2 signal, which subsequently modulate the NLRP3-Nrf2 axis in PD. Nanotechnology promises potential for the advancement of miRNA-based therapies. Nanoparticles that ensure miRNA stability, traverse the blood-brain barrier (BBB) and distribute miRNA targeting regions needed to be created. In conclusion, targeting the pyroptosis pathway via NLRP3 or miRNA may serve as a prospective therapeutic strategy for PD in the future.