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Alzheimer's disease (AD) is a neurodegenerative disease with a long preclinical and prodromal stage near 20 years. The neuropathological hallmarks of AD include amyloid plaques, neurofibrillary tangles, and neuroinflammation, those lead to neuronal and synaptic loss. Important fact, oxidative stress participates in the AD development by promoting amyloid-β deposition, tau hyperphosphorylation. However, the inflammatory response and pyroptotic death are mediated by the aberrant expression of NLRP inflammasome activated caspase-1, which leads to cleavage pro-inflammatory cytokines such as pro-interleukin-1β and pro-IL-18. IL-1β, TNF-α, and IL-6 which amplify the neuroinflammation loop, are produce by activated microglia and astrocytes, that can serve as early diagnostic markers or therapeutic targets in AD. In this review, we summarize our current understanding of the role of inflammasome in the pathogenesis of AD, highlighting key issues that need to be addressed to improve the development of new therapies. [ABSTRACT FROM AUTHOR]

BACKGROUND: Neuroinflammation is an important factor leading to secondary spinal cord injury, and microglia/macrophage pyroptosis is a significant part of post-spinal cord injury neuroinflammation. Studies have shown that microglia/macrophage undergoes pyroptosis after spinal cord injury, but the regulatory mechanism of circular RNA (circRNA) in microglia/macrophage pyroptosis after spinal cord injury remains unclear. OBJECTIVE: To investigate the role and mechanism of circRNA0005512 in regulating microglia/macrophage pyroptosis after spinal cord injury. METHODS: Female Wistar rats were divided into sham group and spinal cord injury group. Motor function was evaluated using the Basso, Beattie, and Bresnahan (BBB) scale. Cavity volume was assessed by hematoxylin-eosin staining. Differential expression of circRNA in spinal cord tissue was screened using RNA-sequencing and circ0005512 was validated by real-time PCR. Immunofluorescence, western blot assay, ELISA, and real-time PCR were performed to detect cell pyroptosis in the rats and lipopolysaccharide-induced microglial cell line HAPI cell models. Gene knockdown was used to confirm the regulatory role of circRNA0005512 in microglia/macrophage pyroptosis. RESULTS AND CONCLUSION: (1) Seven days after spinal cord injury, evident cavities were observed at the injury site. Immediately after spinal cord injury, the motor function of rats was completely lost. Over time, the motor function of rats in the spinal cord injury group gradually partially recovered, and there was a significant difference in BBB scores compared to the sham group. (2) Circ0005512 was significantly upregulated according to the results of the RNAsequencing and confirmed in both the animal and cell models. (3) Immunofluorescence, western blot assay, real-time PCR, and ELISA confirmed the significant upregulation of cell pyroptosis markers (NLRP3, GSDMD, and caspase-1) in spinal cord injury tissue and lipopolysaccharide-induced HAPI cells. (4) In the cell model, knockdown of circ0005512 resulted in significantly decreased levels of cell pyroptosis marker-NLRP3. (5) The results above indicate that circ0005512 promotes pyroptosis in microglia/macrophages after spinal cord injury. [ABSTRACT FROM AUTHOR]

The processes of apoptosis and inflammatory responses, which are defensive strategies used by cells to confront external substances, can give rise to diverse diseases when prolonged or disrupted, such as cancer, Alzheimer's disease, and Parkinson's disease. Here we engineered a live-cell imaging fluorescent probe for nitric oxide (NO) based on naphthalimide and o-phenylenediamine, enabling the sensitive detection of NO in cancer cells and thereby live-monitoring of the doxorubicin-induced apoptosis and lipopolysaccharide-triggered inflammation reactions. Importantly, we found that the level of released NO can sensitively indicate the early stages of both cellular inflammatory responses and apoptotic processes. This suggested that cellular NO in fact behaves as a new class of signaling molecule for inflammatory responses and apoptosis processes, providing a potent tool for live-monitoring cellular physiological reactions. [ABSTRACT FROM AUTHOR]

Objective(s): Myocardial arrhythmia is a major complication of ischemia-reperfusion (I/R) injury in patients with diabetes. Irisin has significant cardioprotective effects, while its role in the pathophysiology of I/R injury-induced myocardial arrhythmia in the presence of diabetes is not well identified. Here, we aimed to investigate the potential antiarrhythmic impacts and mechanisms (mitochondrial biogenesis, endoplasmic reticulum (ER) stress, and pyroptosis) by which irisin reduces I/R injury-induced myocardial arrhythmia in diabetic rats. Materials and Methods: Thirty high-fat diet-induced diabetic rats were subjected to I/R injury and myocardial arrhythmia. Irisin (0.5 µg/kg/day) was injected intraperitoneally before induction of I/R injury. Electrocardiography was used to measure the incidence and severity of ventricular arrhythmias. ELISA and western blotting analyses were employed to quantify the expression of mitochondrial biogenesis, ER stress, and pyroptosis-related proteins in ischemic myocardium. Results: Irisin treatment in diabetic rats significantly decreased the lactate dehydrogenase level and the number and severity of arrhythmia induced by I/R injury. Irisin up-regulated the expression of mitochondrial biogenesis-related proteins while down-regulating the expression of ER stress and pyroptosis-related proteins. Furthermore, the inhibition of mitochondrial quality control by mdivi-1 significantly abolished the cardioprotective effect of irisin. Conclusion: Our findings suggest that irisin reduced myocardial arrhythmia induced by I/R injury in diabetic rats by modulating the interaction of mitochondrial biogenesis and ER stress proteins and inhibiting the pyroptosis pathway. These findings provide a promising strategy for managing myocardial arrhythmia in diabetic patients, but supplementary studies are needed to confirm the clinical efficacy of irisin in these patients. [ABSTRACT FROM AUTHOR]

Hyperoxia-induced acute lung injury (HALI) is a complication of oxygen therapy. Ferroptosis is a vital factor in HALI. This paper was anticipated to investigate the underlying mechanism of wedelolactone (WED) on ferroptosis in HALI. The current study used hyperoxia to injure two models, one HALI mouse model and one MLE-12 cell injury model. We found that WED treatment attenuated HALI by decreasing the lung injury score and lung wet/dry (W/D) weight ratio and alleviating pathomorphological changes. Then, the inflammatory reaction and apoptosis in HALI mice and hyperoxia-mediated MLE-12 cells were inhibited by WED treatment. Moreover, WED alleviated ferroptosis with less iron accumulation and reversed expression alterations of ferroptosis markers, including MDA, GSH, GPX4, SLC7A11, FTH1, and TFR1 in hyperoxia-induced MLE-12 cells in vitro and in vivo. Nrf2-KO mice and Nrf2 inhibitor (ML385) decreased WED's ability to protect against apoptosis, inflammatory response, and ferroptosis in hyperoxia-induced MLE-12 cells. Collectively, our data highlighted the alleviatory role of WED in HALI by activating the Nrf2/HO-1 pathway. [ABSTRACT FROM AUTHOR]

Arsenic, a well-known hazardous toxicant, has been found in recent years to act as an environmental endocrine disruptor that accumulates in various endocrine organs, impeding the normal physiological functions of these organs and altering hormone secretion levels. Moreover, some research has demonstrated a correlation between arsenic exposure and thyroid functions, suggesting that arsenic has a toxicological effect on the thyroid gland. However, the specific type of thyroid gland damage caused by arsenic exposure and its potential molecular mechanism remain poorly understood. In this study, the toxic effects of sodium arsenite (NaAsO2) exposure at different doses (0, 2.5, 5.0 and 10.0 mg/kg bw) and over different durations (12, 24 and 36 weeks) on thyroid tissue and thyroid hormone levels in Sprague‒Dawley (SD) rats were investigated, and the specific mechanisms underlying the effects were also explored. Our results showed that NaAsO2 exposure can cause accumulation of this element in the thyroid tissue of rats. More importantly, chronic exposure to NaAsO2 significantly upregulated the expression of NLRP3 inflammasome-related proteins in thyroid tissue, leading to pyroptosis of thyroid cells and subsequent development of thyroid dysfunction, inflammatory injury, epithelial–mesenchymal transition (EMT), and even fibrotic changes in the thyroid glands of SD rats. These findings increase our understanding of the toxic effects of arsenic exposure on the thyroid gland and its functions. [ABSTRACT FROM AUTHOR]

In the realm of combined cancer immunotherapy, the strategic combination of therapeutics targeting both cancer cells and macrophages holds immense potential. However, the major challenges remain on how to achieve facile spatiotemporal delivery of these therapies, allowing ease of manipulation and ensuring differential drug release for enhanced synergistic therapeutic effects. In the present study, we introduced a tumor microenvironment (TME)-adapted hydrogel with the phenylboronic acid-modified dipyridamole prodrug (DIPP) as a crosslinker. This prodrug hydrogel scaffold, 3BP@DIPPGel, could be formed in situ by a simple mixture of DIPP and poly(vinyl alcohol) (PVA), and loaded with a high ratio of 3-bromopyruvic acid (3BP). The 3BP@DIPPGel enables spatiotemporal localized delivery of dipyridamole (DIP) and 3BP with distinct release kinetics that effectively reshape the immunosuppressive TME. Upon reactive oxygen species (ROS) stimulation, 3BP@DIPPGel preferentially released 3BP, inducing tumor-specific pyroptosis via the ROS/BAX/caspase-3/GSDME signaling pathway and decreasing the secretion of chemokines such as CCL8 to counteract macrophage recruitment. Subsequently, the crosslinked DIP is released, triggering the tumor-associated macrophages (TAMs) polarization towards the immunostimulatory M1 phenotype via the CCR2/JAK2/STAT3 cascade signaling pathway. This dual action from 3BP@DIPPGel leads to the restoration of tumor cell immunogenicity with high efficacy and activation of immune cells. Furthermore, the 3BP@DIPPGel-based chemoimmunotherapy upregulates the expression of sialic-acid-binding Ig-like lectin 10 and hence sensitizing tumors to anti-CD24 therapy in the tumor-bearing mice. Therefore, this strategy can have significant potential in the prevention of tumor metastases and recurrence. To the best of our understanding, this study represents a pioneering showcase of tumor pyroptosis, induced by glycolytic inhibitors, which can be effectively coordinated with DIP-mediated TAM polarization for immune activation, offering a new paradigm for differentially sustained drug delivery to foster cancer immunotherapy. A facile translatable scaffold 3BP@DIPPGel comprising a ROS-responsive dipyridamole prodrug (DIPP) hydrogel DIPPGel and an encapsulated glycolytic inhibitor 3-bromopyruvic acid (3BP) was developed. The 3BP@DIPPGel enables delivery of dipyridamole and 3BP with distinct release kinetics. Upon ROS stimulation, 3BP@DIPPGel preferentially released 3BP, inducing tumor-specific pyroptosis and counteracting macrophage recruitment. Subsequently, the crosslinked DIP is released, triggering macrophage polarization towards the immunostimulatory M1 phenotype. This dual action from 3BP@DIPPGel leads to the restoration of tumor cell immunogenicity and activation of immune cells. [Display omitted] • ROS-responsive prodrug hydrogel scaffold 3BP@DIPPGel was formed by phenylboronic acid-modified dipyridamole prodrug and 3BP-loaded PVA. • In the scaffold 3BP@DIPPGel, DIPP allowed the scaffold to exploit the ROS within tumors for the spatiotemporally sustained delivery of dipyridamole and 3BP with different release kinetics. • This 3BP@DIPPGel approach can effectively reverse tumor immunosuppression and promote antitumor immune responses by inducing tumor-specific pyroptosis and triggering macrophage polarization. • 3BP@DIPPGel plus anti-CD24 therapy provided long-term immune memory against tumor metastases and recurrence in mice. [ABSTRACT FROM AUTHOR]

Cerebral ischemia reperfusion injury is a severe neurological impairment that occurs after blood flow reconstruction in stroke, and microglia cell pyroptosis is one of its important mechanisms. Electroacupuncture has been shown to be effective in mitigating and alleviating cerebral ischemia reperfusion injury by inhibiting neuroinflammation, reducing cellular pyroptosis, and improving neurological function. In this experiment, we divided the rats into three groups, including the sham operation (Sham) group, the middle cerebral artery occlusion/reperfusion (MCAO/R) group, and the pre-electroacupuncture (EAC) group. Pre-electroacupuncture group was stimulated with electroacupuncture of a certain intensity on the Baihui (GV 20) and Dazhui (GV 14) of the rat once a day from the 7th day to the 1st day before the MCAO/R operation. The extent of cerebral infarction was detected by TTC staining. A modified Zea-Longa five-point scale scoring system was used to determine neurologic function in MCAO rats. The number of neurons and morphological changes were accessed by Nissl staining and HE staining. The cellular damage was detected by TUNEL staining. In addition, the expression levels of RhoA, pyrin, GSDMD, Caspase1, cleaved-Caspase1, Iba-1, CD206, and ROCK2 were examined by western blotting and immunofluorescence. The results found that pre-electroacupuncture significantly attenuated neurological impairment and cerebral infarction compared to the post-MCAO/R rats. In addition, pre-electroacupuncture therapy promoted polarization of microglia to the neuroprotective (M2) phenotype. In addition, pre-electroacupuncture inhibited microglia pyroptosis by inhibiting RhoA/pyrin/GSDMD signaling pathway, thereby reducing neuronal injury and increasing neuronal survival in the MCAO/R rats. Taken together, these results demonstrated that pre-acupuncture could attenuate cerebral ischemia-reperfusion injury by inhibiting microglial pyroptosis. Therefore, pre-electroacupuncture might be a potential preventive strategy for ischemic stroke patients. Hightlights: 1. Pre-electroacupuncture can decrease cerebral infarct volume after stroke. 2. Pre-electroacupuncture can effectively reduce neuroinflammation and inhibit microglia pyroptosis. 3. Pre-electroacupuncture can inhibit pyroptosis by RhoA/pyrin/GSDMD pathway. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a debilitating and the second most common neurodegenerative disorder with a high prevalence. PD has a multifaceted etiology characterized by an altered redox state and an excessive inflammatory response. Extensive research has consistently demonstrated the role of the nuclear factor E2-related factor (Nrf2) and inflammasomes, notably NLRP3 in neurodegenerative diseases. In this study, our focus was on exploring the potential neuroprotective properties of carveol in Parkinson's disease. Our findings suggest that carveol may exhibit these effects through Nrf2 and by suppressing pyroptosis. Male albino mice were treated with carveol, and the animal PD model was induced through a single intranigral dose of 2 µg/2µl lipopolysaccharide (LPS). To further demonstrate the essential role of the Nrf2 pathway, we utilized all-trans retinoic acid (ATRA) to inhibit the Nrf2. Our finding showed the induction of pyroptosis as evidenced by increased levels of NLRP3 and other inflammatory mediators, including IL-1β, iNOS, p-NFKB, and apoptotic cell death indicated by positive fluoro Jade B (FJB) staining. Moreover, increased levels of lipid peroxides and reactive oxygen species indicated a significant rise in oxidative stress due to LPS. The administration of carveol mitigates oxidative stress and suppresses inflammatory pathways through the augmentation of intrinsic antioxidant defenses, primarily via the activation of the Nrf2. Conversely, ATRA reversed carveol protective effects by increasing FJB-positive cells, inflammatory and oxidative biomarkers. Taken together, our findings suggest that carveol mitigated LPS-induced Parkinson-like symptoms, partially through the activation of the Nrf2 and downregulation of pyroptosis notably NLRP3. [ABSTRACT FROM AUTHOR]

The inflammasome is a multiprotein complex involved in innate immunity that mediates the inflammatory response leading to pyroptosis, which is a lytic, inflammatory form of cell death. There is accumulating evidence that nucleotide-binding domain and leucine-rich repeat pyrin domain containing 3 (NLRP3) inflammasome-mediated microglial pyroptosis and NLRP1 inflammasome-mediated neuronal pyroptosis in the brain are closely associated with the pathogenesis of Alzheimer's disease. In this review, we summarize the possible pathogenic mechanisms of Alzheimer's disease, focusing on neuroinflammation. We also describe the structures of NLRP3 and NLRP1 and the role their activation plays in Alzheimer's disease. Finally, we examine the neuroprotective activity of small-molecule inhibitors, endogenous inhibitor proteins, microRNAs, and natural bioactive molecules that target NLRP3 and NLRP1, based on the rationale that inhibiting NLRP3 and NLRP1 inflammasome-mediated pyroptosis can be an effective therapeutic strategy for Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common neurodegenerative disease all over the world. In the last decade, accumulating proofs have evidenced that neuroinflammation is intimately implicated in the pathogenesis of AD and activation of NOD-like receptor family pyrin domain–containing 1 (NLRP1) inflammasome can induce neuronal pyroptosis and in turn lead to neuronal loss in AD. Thioredoxin-1 (Trx-1), a multifunctional molecule with anti-inflammation in human tissues, displays crucial neuroprotective roles in AD. Our previous research preliminarily found that Trx-1 inhibition enhanced the expression of NLRP1, caspase-1, and gasdermin D (GSDMD) in Aβ25–35-treated PC12 cells. However, it is largely unknown if Trx-1 can inhibit NLRP1-mediated neuronal pyroptosis in AD neurons. In this study, it was verified that the protein levels of NLRP1, caspase-1, and GSDMD were significantly increased in Aβ25–35-treated mouse HT22 and primary hippocampal neurons. Suppression of Trx-1 with PX-12, a selective inhibitor of Trx-1, or Trx-1 knockdown further activated NLRP1-mediated neuronal pyroptosis. On the contrary, lentivirus infection–mediated Trx-1 overexpression in differentiated PC12 cells dramatically reversed expression of NLRP1, caspase-1, and GSDMD. Furthermore, Trx-1 overexpression mediated by adeno-associated virus in the hippocampal tissues of APP/PS1 mice likewise attenuated the activation of NLRP1-mediated neuronal pyroptosis, as well as reduced the hippocampal deposition of Aβ and ameliorated the cognitive function of APP/PS1 mice. In conclusion, this article predicates a novel molecular mechanism by which Trx-1 exploits neuroprotection through attenuating NLRP1-mediated neuronal pyroptosis in AD models, suggesting that Trx-1 may be a promising therapeutic target for AD. [ABSTRACT FROM AUTHOR]

Neuroinflammation is a common pathological feature in a number of neurodegenerative diseases, which is mediated primarily by the activated glial cells. Nucleotide-binding oligomerization domain-like receptor pyrin domain-containing-3 (NLRP3) inflammasome-associated neuroinflammatory response is mostly considered. To investigate the situation of the NLRP3-related inflammation in prion disease, we assessed the levels of the main components of NLRP3 inflammasome and its downstream biomarkers in the scrapie-infected rodent brain tissues. The results showed that the transcriptional and expressional levels of NLRP3, caspase-1, and apoptosis-associated speck-like protein (ASC) in the brains of scrapie-infected rodents were significantly increased at terminal stage. The increased NLPR3 overlapped morphologically well with the proliferated GFAP-positive astrocytes, but little with microglia and neurons. Using the brain samples collected at the different time-points after infection, we found the NLRP3 signals increased in a time-dependent manner, which were coincidental with the increase of GFAP. Two main downstream cytokines, IL-1β and IL-18, were also upregulated in the brains of prion-infected mice. Moreover, the gasdermin D (GSDMD) levels, particularly the levels of GSDMD-NT, in the prion-infected brain tissues were remarkably increased, indicating activation of cell pyroptosis. The GSDMD not only co-localized well with the astrocytes but also with neurons at terminal stage, also showing a time-dependent increase after infection. Those data indicate that NLRP3 inflammasomes were remarkably activated in the infected brains, which is largely mediated by the proliferated astrocytes. Both astrocytes and neurons probably undergo a pyroptosis process, which may help the astrocytes to release inflammatory factors and contribute to neuron death during prion infection. [ABSTRACT FROM AUTHOR]

The health risks associated with microplastics have attracted widespread attention. Polystyrene microplastics (PS‐MPs) can induce damage to cardiac tissue, while pyroptosis‐mediated injury to the vascular endothelial plays a vital role in the pathogenesis of cardiovascular diseases. The study intended to explore the role and mechanism of NLR family pyrin domain containing 3 (NLRP3) mediated pyroptosis in PS‐MPs causing the injury of vascular endothelial cells. In vivo, Wistar rats were exposed to 0.5, 5, and 50 mg/kg/d 0.5 μm PS‐MPs. In vitro, the human vascular endothelial cells (HUVECs) were used for mechanistic studies. siRNA was used for silencing the NILRP3 gene. H&E staining and flow cytometry were performed to examine the vascular injury and cell membrane damage. The oxidative stress was detected by flow cytometry, immunofluorescence, and corresponding kits. ELISA were used to measure the levels of inflammatory factors. Real‐time PCR and western blot were used to measure the expression of pyroptosis signaling pathway. In rats, PS‐MPs could cause vascular damage, oxidative stress, and inflammatory response, and activated the pyroptosis signaling pathway. HUVECs exposure to PS‐MPs, the vitality decreased in a dose‐dependent manner, ROS and MDA were significantly increased while SOD was decreased. PS‐MPs induced the onset of pyroptosis signaling pathway in HUVECs. Cell membrane damage and the levels of IL‐Iβ and IL‐18 in HUVECs significantly increased, those are symbols for the development of pyroptosis. Inhibition of NLRP3‐mediated pyroptosis effectively protected HUVECs from PS‐MPs‐induced damage. Pyroptosis played a vital role in controlling the vascular endothelial injury caused by PS‐MPs. [ABSTRACT FROM AUTHOR]

Trimethyltin chloride (TMT) is a highly toxic organotin pollutant frequently found in aquatic environments, posing a significant threat to the ecological system. The kidney plays a vital role in the body's detoxification processes, and TMT present in the environment tends to accumulate in the kidneys. However, it remained unclear whether exposure to different doses of TMT could induce pyroptosis and immune dysfunction in grass carp kidney cells (CIK cells). For this purpose, after assessing the half‐maximal inhibitory concentration (IC50) of TMT on CIK cells, we established a model for exposure of CIK cells at varying concentrations of TMT. CIK cells were treated with various doses of TMT (2.5, 5, 10 μM) for 24 h. Oxidative stress levels were measured using kits and fluorescence methods, whereas the expression of related genes was verified through western blot and quantitative real‐time PCR (qRT‐PCR). The results indicated that TMT exposure led to oxidative stress, with increased levels of ROS, H2O2, MDA, and GSH, and inhibited activities of T‐AOC, SOD, and CAT. It activated the NF‐κB pathway, leading to the upregulation of NF‐κB p65, NF‐κB p50, GSDMD, NLRP3, ASC, and Caspase‐1. Furthermore, TMT exposure also resulted in increased expression of cytokines (IL‐18, IL‐6, IL‐2, IL‐1β, and TNF‐α) and decreased expression of antimicrobial peptides (LEAP2, HEPC, and β‐defensin). In summary, exposure to TMT induces dose‐dependent oxidative stress that activates the NF‐κB pathway, leading to pyroptosis and immune dysfunction in grass carp CIK cells. [ABSTRACT FROM AUTHOR]

Gasdermin-mediated inflammatory cell death (pyroptosis) can activate protective immunity in immunologically cold tumors. Here, we performed a high-throughput screen for compounds that could activate gasdermin D (GSDMD), which is expressed widely in tumors. We identified 6,7-dichloro-2-methylsulfonyl-3-N-tert-butylaminoquinoxaline (DMB) as a direct and selective GSDMD agonist that activates GSDMD pore formation and pyroptosis without cleaving GSDMD. In mouse tumor models, pulsed and low-level pyroptosis induced by DMB suppresses tumor growth without harming GSDMD-expressing immune cells. Protection is immune-mediated and abrogated in mice lacking lymphocytes. Vaccination with DMB-treated cancer cells protects mice from secondary tumor challenge, indicating that immunogenic cell death is induced. DMB treatment synergizes with anti-PD-1. DMB treatment does not alter circulating proinflammatory cytokine or leukocyte numbers or cause weight loss. Thus, our studies reveal a strategy that relies on a low level of tumor cell pyroptosis to induce antitumor immunity and raise the possibility of exploiting pyroptosis without causing overt toxicity. [Display omitted] • A GSDMD agonist (DMB) modifies Cys191 and causes cleavage-independent pyroptosis • DMB induces antitumor immunity, dependent on GSDMD expression in tumor, not host • Vaccination with DMB-treated tumor protects mice from tumor rechallenge • DMB synergies with checkpoint blockade therapy, reducing cold tumor growth Pyroptosis is an immunogenic cell death that can promote antitumor immunity. This study identified a small molecule agonist of GSDMD that induced GSDMD pore formation and pyroptosis without cleavage and showed that pulsed and low-level pyroptosis induction in cancer cells is a strategy for cancer immunotherapy with little toxicity. [ABSTRACT FROM AUTHOR]

Introduction: Pyroptosis is an inflammatory form of programmed cell death that plays a significant role in tumorigenesis. Cinobufotalin (CB), a bufadienolide extracted from toad venom, is associated with antitumor effects in various cancers, including liver cancer. However, the role of CB in pyroptosis and its underlying mechanisms have not been well characterized. Methods: MTT, Colony formation, EdU, Wound healing and Transwell migration and invasion assays were applied to determine the effects of CB on the proliferation, migration, and invasion ability of hepatocellular carcinoma (HCC) cells in vitro. The subcutaneous xenograft mouse model and pulmonary metastasis model were used to evaluate the effect of CB on HCC cells in vivo. PCR, western blot, immunohistochemistry, immunofluorescence, and ELISA were used to verify the expression of proliferation, migration, pyroptosis, and inflammation related molecules after CB treatment. Using si-RNA and inhibitors to interfere with NOX4 and HLRP3 expression to validate the key signaling pathways of pyroptosis induced by CB treatment. Results: In vivo experiments using nude mice with xenografted HCC cells and in vitro experiments with HCC cell lines demonstrated that CB treatment significantly inhibited the proliferation, migration, and invasiveness of HCC cells. CB treatment also showed dose-dependent activation of the NLRP3 inflammasome complex in HCC cells, leading to gasdermin D-induced pyroptosis. However, these effects were abrogated via the pretreatment of HCC cells with VX-765, a caspase-1 inhibitor. Additionally, CB increased the production of reactive oxygen species (ROS) and H2O2, along with upregulating NOX4 protein expression in HCC cells. Conversely, NOX4 silencing or pretreatment with VAS2870 (an NOX4 inhibitor) or NAC (an ROS scavenger) suppressed the activation of the NLRP3 inflammasome complex and pyroptosis in CB-treated HCC cells. Discussion: Our study demonstrated that CB suppressed the proliferation, migration, and invasiveness of HCC cells by inducing pyroptosis through the activation of the NOX4/NLRP3/GSDMD signaling pathway. Therefore, our results suggest that CB is a promising therapeutic agent for HCC. [ABSTRACT FROM AUTHOR]

Background: Abdominal aortic aneurysm (AAA) represents a permanent and localized widening of the abdominal aorta, posing a potentially lethal risk of aortic rupture. Several recent studies have highlighted the role of pyroptosis, a pro‐inflammatory programed cell death, as critical molecular regulators in AAA occurrence, progression, and rupture. However, the potential effects of pyroptosis in AAA and its upstream microRNA (miRNA) have not been comprehensively clarified. Methods: Through a search of the gene expression omnibus (GEO) database, the expression profiles of mRNAs (GSE7084, GSE57691, and GSE98278) and miRNAs (GSE62179) and corresponding clinical features were downloaded, respectively. Expression profiles of 15 AAA and 10 normal vascular samples were consecutively collected for in vitro experimentation and subsequent analysis. Various machine learning techniques were employed to identify hub pyroptosis‐related genes (PRGs), leading to the development of a predictive model termed the PRG classifier. Quantitative real‐time‐polymerase chain reaction (qRT‐PCR), western blot (WB), and enzyme‐linked immunosorbent assay (ELISA) were used to confirm the expression of the hub PRGs. The diagnostic and predictive capabilities of the model were comprehensively evaluated in GEO and hospital cohorts. Then, the crucial immune cell infiltration and molecular pathways implicated in the initiation and rupture of AAA and their association with pyroptosis were explored. Lastly, a miRNA/hub pyroptosis‐related molecular regulatory axis was constructed using the TargetScan dataset, which was further explored through loss‐of‐function assays. Results: Differential analysis, enrichment score analysis, and principal component analysis (PCA) revealed that pyroptosis‐related molecules were significantly involved in the occurrence of AAA. Utilizing multiple machine learning algorithms, eight key PRGs (cysteinyl aspartate specific proteinase [CASP]1, infiltrating lymphocyte [IL]1B, IL18, IL6, NOD‐, LRR‐ and pyrin domain‐containing protein [NLRP]1, NLRP2, NLRP3, and tumor necrosis factor [TNF]) were integrated to establish a PRG classifier. Demonstrating robust diagnostic capabilities (area under curve [AUC] > 0.90), the PRG classifier provided clinical insights across two GEO datasets and effectively differentiated small AAA from large AAA, elective stable AAA (eAAA), and ruptured AAA (rAAA), respectively. qRT‐PCR, WB, and ELISA verified the mRNA and protein expression of the hub PRGs. Notably, in hospital cohorts, a substantial positive link was unveiled between the PRG classifier and AAA risk factors (hypertension history, diastolic pressure, triglyceride levels, and aneurysm diameter). Furthermore, immune cell infiltration and functional enrichment analysis revealed significant associations of the PRG classifier/PRGs with M2 macrophage infiltration, activated dendritic cells, and enrichment scores of the cytosolic deoxyribonucleic acid (DNA) sensing pathway and tryptophan metabolism, potentially mediating AAA onset and rupture. Finally, based on 90 differentially expressed miRNAs (DEmiRNAs) and eight hub PRGs through TargetScan dataset, a hsa‐miR‐331‐3p/TNF regulatory axis was constructed, wherein upregulation of hsa‐miR‐331‐3p expression significantly reduced TNF and CASP1 protein levels. Conclusion: A predictive model (PRG classifier) incorporating eight PRGs through multiple machine learning algorithms was developed and validated. This model may stand as a potent tool for diagnosing AAA and assessing disease severity. The identification of the cytosolic DNA sensing pathway and the hsa‐miR‐331‐3p/TNF interaction axis may represent crucial targets for AAA treatment, offering deeper insights into its potential pathogenesis. [ABSTRACT FROM AUTHOR]

Pyroptosis is a gasdermin-mediated pro-inflammatory form of programmed cell death (PCD). Tumor necrosis factor-ɑ (TNF-ɑ) is an inflammatory cytokine, and some studies have shown that TNF-ɑ can cause pyroptosis of cells and exert anti-tumor effects. However, whether TNF-ɑ exerts anti-tumor effects on breast cancer cells by inducing pyroptosis has not been reported. In this study, to explore the impact of TNF-ɑ on pyroptosis in breast cancer cells, we treated MCF-7 cells with TNF-ɑ and found that TNF-ɑ induced cell death. Moreover, we observed that the dead cells were swollen with obvious balloon-like bubbles, which was a typical sign of pyroptosis. Further studies have found that the anti-tumor effect of TNF-ɑ on breast cancer cells in vitro was achieved through the canonical pyroptosis pathway. In addition, TNF-ɑ-induced pyroptosis in MCF-7 cells was associated with mitochondrial dysfunction, in which mitochondrial membrane potential was decreased and mitochondrial ROS production was increased. After inhibiting ROS production, the activation effect of TNF-ɑ on NLRP3/Caspase-1/GSDMD pathway was weakened, and the inhibitory effect of TNF-ɑ on the growth of MCF-7 cells in vitro was also decreased, further confirming the involvement of ROS in TNF-ɑ-induced pyroptosis. Overall, our study revealed a new mechanism by which TNF-ɑ exerts an anti-tumor effect by inducing pyroptosis in MCF-7 cells through the ROS/NLRP3/Caspase-1/GSDMD pathway, which may provide new therapeutic ideas for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

A short peptide termed NEMO‐binding domain (NBD) peptide has an inhibitory effect on nuclear factor kappa‐B (NF‐κB). Despite its efficacy in inhibiting inflammatory responses, the precise neuroprotective mechanisms of NBD peptide in spinal cord injury (SCI) remain unclear. This study aims to determine whether the pyroptosis‐related aspects involved in the neuroprotective effects of NBD peptide post‐SCI.Using RNA sequencing, the molecular mechanisms of NBD peptide in SCI are explored. The evaluation of functional recovery is performed using the Basso mouse scale, Nissl staining, footprint analysis, Masson's trichrome staining, and HE staining. Western blotting, enzyme‐linked immunosorbent assays, and immunofluorescence assays are used to examine pyroptosis, autophagy, lysosomal membrane permeabilization (LMP), acid sphingomyelinase (ASMase), and the NF‐κB/p38‐MAPK related signaling pathway.NBD peptide mitigated glial scar formation, reduced motor neuron death, and enhanced functional recovery in SCI mice. Additionally, NBD peptide inhibits pyroptosis, ameliorate LMP‐induced autophagy flux disorder in neuron post‐SCI. Mechanistically, NBD peptide alleviates LMP and subsequently enhances autophagy by inhibiting ASMase through the NF‐κB/p38‐MAPK/Elk‐1/Egr‐1 signaling cascade, thereby mitigating neuronal death. NBD peptide contributes to functional restoration by suppressing ASMase‐mediated LMP and autophagy depression, and inhibiting pyroptosis in neuron following SCI, which may have potential clinical application value. [ABSTRACT FROM AUTHOR]

The vigorous development of cancer nanomedicine has revolutionized traditional oncology medicine, but it is also limited by the continuous mutation of cunning cancer cells, leading to apoptosis insensitivity and therapeutic disappointment. Inflammatory‐regulated cell death (RCD), especially pyroptosis‐related cell death, demonstrates huge potential for apoptosis sensitization due to its unique biochemical characteristics. The aim of this research is to present a thorough synopsis of the current knowledge on pyroptosis‐associated inflammatory cell death, including pyroptosis, cuproptosis, and PANoptosis, and the synergistic function in cancer nano therapy. Paradigm studies of pyroptosis‐related cell death‐mediated apoptosis‐sensitizing tumor nanotherapeutics are introduced in detail, and the coordination mechanisms based on nanomaterials are also discussed. In addition, multi‐angle analysis of the future prospects of pyroptosis‐sensitized tumor nanomedicine based on various nanomaterials is also emphasized to further expand the application scope of inflammatory RCD. It is believed that emerging auxiliary apoptosis‐sensitizing treatments based on inflammatory RCD will greatly promote the progress of cancer nanomedicine. [ABSTRACT FROM AUTHOR]

In sepsis, inflammation, and nutrient deficiencies endanger cellular homeostasis and survival. Autophagy is primarily a mechanism of cellular survival under fasting conditions. However, autophagy-dependent cell death, known as autophagic cell death, is proinflammatory and can exacerbate sepsis. Autophagy also regulates various types of non-inflammatory and inflammatory cell deaths. Non-inflammatory apoptosis tends to suppress inflammation, however, inflammatory necroptosis, pyroptosis, ferroptosis, and autophagic cell death lead to the release of inflammatory cytokines and damage-associated molecular patterns (DAMPs) and amplify inflammation. The selection of cell death mechanisms is complex and often involves a mixture of various styles. Similarly, protective autophagy and lethal autophagy may be triggered simultaneously in cells. How cells balance the regulatory mechanisms of these processes is an area of interest that is still under investigation. Therapies aimed at modulating autophagy are considered promising. Enhancing autophagy helps clear and recycle damaged organelles and reduce the burden of inflammatory processes while inhibiting excessive autophagy, which could prevent autophagic cell death. In this review, we introduce recent advances in research and the complex regulatory system of autophagy in sepsis. [ABSTRACT FROM AUTHOR]

Pyroptosis possesses potent antitumor immune activity, making pyroptosis inducer development a promising direction for tumor immunotherapy. Persistent luminescence nanoparticles (PLNPs) are highly sensitive optical probes extensively employed in tumor diagnosis and therapy. However, a pyroptosis inducer based on PLNPs has not been reported yet. Herein, polyethylene glycol–poly lactic acid‐co‐glycolic acid (PEG–PLGA: PP) modified biodegradable CaS:Eu2+ (CSE@PP) PLNPs are synthesized as a pyroptosis inducer for tumor immunotherapy for the first time. The synthesized CSE@PP possesses biowindow persistent luminescence (PersL) and pH‐responsive degradation properties, allowing it to remain stable under neutral pH but degrade when exposed to weak acid (pH < 6.5). During degradation within the tumor, CSE@PP constantly releases H2S and Ca2+ while its PersL gradually fades away. Thus, the PersL signal can self‐monitor H2S and Ca2+ release. Furthermore, the released H2S and Ca2+ result in mitochondrial dysfunction and the inactivation of reactive oxygen species scavenging enzymes, synergistic facilitating intracellular oxidative stress, which induces caspase‐1/GSDM‐D dependent pyroptosis and subsequent antitumor immune responses. In a word, it is confirmed that CSE@PP can self‐monitor H2S and Ca2+ release and pyroptosis‐mediated tumor Immunotherapy. This work will facilitate biomedical applications of PLNPs and inspire pyroptosis‐induced tumor immunotherapy. [ABSTRACT FROM AUTHOR]

Objective: This research is aimed at unravelling the intricate relationship between transient receptor potential vanilloid 6 (TRPV6), protein kinase A (PKA), uncoupling protein 2 (UCP2), and atherosclerosis. By shedding light on the role of the TRPV6/PKA/UCP2 pathway in inhibiting inflammatory response and cell apoptosis in coronary atherosclerotic plaques, this study provides valuable insights into potential therapeutic targets for treating coronary artery disease (CAD). Methods: We established animal and cell models of atherosclerosis. The expression of TRPV6 was measured using immunohistochemistry and immunofluorescence. Cytokine levels were detected by enzyme‐linked immunosorbent assay (ELISA). Cell viability and apoptosis ratio were measured using cell counting kit‐8 (CCK‐8) and flow cytometry. The binding relationship between TRPV6 and PKA was validated using chromatin immunoprecipitation (CHIP) and coimmunoprecipitation (CoIP). Finally, the expression of the TRPV6/PKA/UCP2 signaling pathway and apoptosis‐related factors was detected using western blot (WB) and quantitative real‐time polymerase chain reaction (qRT‐PCR). Results: TRPV6 was significantly decreased in atherosclerosis mouse and cell model. CHIP and CoIP assays indicated that TRPV6 binds to PKA and positively regulated its expression in oxidized low‐density lipoprotein (ox‐LDL)–treated human umbilical vein endothelial cells (HUVECs). Overexpression of TRPV6 significantly increased cell viability and inhibited apoptosis, whereas silencing TRPV6 had the opposite effect. Additionally, the overexpression of TRPV6 remarkably declined the expression of tumor necrosis factor‐alpha (TNF‐α), interleukin‐6 (IL‐6), and interleukin‐1 beta (IL‐1β). However, after silencing PKA, this effect was partially reversed, the cell viability and inflammatory response remarkably enhanced, and apoptosis significantly declined in oe‐TRPV6 + si‐PKA group. Conclusions: In summary, our study demonstrated that TRPV6 inhibited apoptosis and inflammatory response in the atherosclerosis cell model through the regulation of the PKA/UCP2 pathway. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis is a chronic autoimmune disease of undetermined etiology characterized by symmetric synovitis with predominantly destructive and multiple joint inflammation. Cytoplasmic DNA sensors that recognize protein molecules that are not themselves or abnormal dsDNA fragments play an integral role in the generation and perpetuation of autoimmune diseases by activating different signaling pathways and triggering innate immune signaling pathways and host defenses. Among them, melanoma deficiency factor 2 (AIM2) recognizes damaged DNA and double-stranded DNA and binds to them to further assemble inflammasome, initiating the innate immune response and participating in the pathophysiological process of rheumatoid arthritis. In this article, we review the research progress on the source of cytoplasmic DNA, the mechanism of assembly and activation of AIM2 inflammasome, and the related roles of other cytoplasmic DNA sensors in rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration (IVDD) is a primary contributor to low back pain and poses a considerable burden to society. However, the molecular mechanisms underlying IVDD remain to be elucidated. PR/SET domain 1 (PRDM1) regulates cell proliferation, apoptosis, and inflammatory responses in various diseases. Despite these regulatory functions, the mechanism of action of PRDM1 in IVDD remains unexplored. In this study, we investigated the role and underlying mechanisms of action of PRDM1 in IVDD progression. The expression of PRDM1 in nucleus pulposus (NP) tissues and NP cells (NPCs) was assessed using western blotting, immunohistochemistry, and immunofluorescence. The effects of PRDM1 on IVDD progression were investigated in vitro and in vivo. Mechanistically, mRNA sequencing, chromatin immunoprecipitation, and dual-luciferase reporter assays were performed to confirm that PRDM1 triggered CASP1 transcription. Our study demonstrated for the first time that PRDM1 expression was substantially upregulated in degenerated NP tissues and NPCs. PRDM1 overexpression promoted NPCs pyroptosis by inhibiting mitophagy and exacerbating IVDD progression, whereas PRDM1 silencing exerted the opposite effect. Furthermore, PRDM1 activated CASP1 transcription, thereby promoting NPCs pyroptosis in vitro. Notably, CASP1 silencing reversed the effects of PRDM1 on the NPCs. To the best of our knowledge, this study is the first to demonstrate that PRDM1 silencing inhibits NPCs pyroptosis by repressing CASP1 transcription, which may be a promising new therapeutic target for IVDD. [ABSTRACT FROM AUTHOR]

Radiotherapy is used in the treatment of ≈50% of patients with cancer. However, tumor repopulation is a major cause of treatment failure after radiotherapy. It is observed that apoptotic tumor following ionizing radiation (IR) accelerated the growth of surviving tumor cells. Here a Gasdermin E and Tannic acid‐based nanoassembly (GT) loaded with manganese tetroxide (Mn3O4) (termed as Mn3O4@GT) is developed to suppress tumor repopulation and improve the treatment outcome of radiotherapy. Mn3O4@GT enables an increase in the reactive oxygen species accumulation in tumor cells, enhancing radiotherapy‐mediated tumor killing. What's more, it can hijack activated caspase 3 to induce tumor pyroptosis, reversing apoptosis‐mediated tumor repopulation. In vivo results shows that Mn3O4@GT significantly reduced the IR induced tumor repopulation by 2.7 fold, resulting in 92% complete regression of tumors. In addition, Mn3O4@GT can sensitize tumors to anti‐PD‐L1 therapy by inducing immunogenic pyroptosis with 85% regression of distant tumors. The caspase 3‐hijacking nanosystem holds a great potential for improving the clinical benefits of radiotherapy. [ABSTRACT FROM AUTHOR]

Mastitis is a common disease worldwide that affects the development of the dairy industry due to its high incidence and complex etiology. Precise regulation of cell death and survival plays a critical role in maintaining internal homeostasis, organ development, and immune function in organisms, and regulatory abnormalities are a common mechanism of various pathological changes. Recent research has shown that regulated cell death (RCD) plays a crucial role in mastitis. The development of drugs to treat cell death and survival abnormalities that can be widely used in mastitis treatment has important clinical significance. This paper will review the molecular mechanisms of apoptosis, autophagy, pyroptosis, ferroptosis, and necroptosis and their regulatory roles in mastitis to provide a new perspective for the targeted treatment of mastitis. [ABSTRACT FROM AUTHOR]

Nucleotide-binding oligomerization domain (NOD)-like receptor (NLR) inflammasomes are multiprotein signaling platforms that control the inflammatory response and coordinate antimicrobial defense. In the present study, the distribution of NLR, Caspase-1, and gasdermin (GSDM) homologues and their structural characteristics and evolutionary relationships were systematically analyzed in metazoa according to the genomes of species. In invertebrates, there were only NLRC and/or NLRD presented from sponge to amphioxus, and according to the evolutionary tree, NLR from sponge located in the most primitive position. Caspase-1 existed in some metazoan phyla (Brachiopoda, Ectoprocta, Arthropoda, Mollusca, Annelia, Nematoda, Platyelminthes, Coelenterate, and Porifera) and its activation sites were relatively conserved. The amino acid sequences and three-dimensional structures of N-terminal CARD/Death domain of NLR and Caspase-1 were similar in species from sponge to human. NLR and Caspase-1 co-existed in species of Brachiopoda, Mollusca, Annelia, Coelenterate, and Porifera. There was only GSDME or PJVK found in some phyla of invertebrates and their cleavage sites were conserved (DxxD). And it was predicted that the NLR inflammasome in inducing pyroptosis could occur in species of Brachiopoda, Mollusca, Annelia, and Coelenterate. These studies indicated that NLR inflammasome emerged early in sponges of metazoa, and NLR inflammasome in inducing pyroptosis first appeared in Coelenterate, suggesting that inflammasome and its mediated pyroptosis had existed in the early stage of metazoa, but they had been lost in many species during evolution. [ABSTRACT FROM AUTHOR]

AbstractIsoquercitrin possesses anti-tumor activity in several types of cancers, however, its effects and underlying mechanisms on lung cancer have not been reported. Human lung cancer cell lines as well as normal lung epithelial BEAS-2B cells were treated with isoquercitrin. The influences of isoquercitrin in vitro were evaluated by determining cell viability, apoptosis, pyroptosis, and ferroptosis. Additionally, A549 tumor-bearing mice were generated to explore the anti-cancer effect of isoquercitrin in vivo. We found that isoquercitrin dose-dependently reduced lung cancer cells’ viability, with no toxicity against BEAS-2B cells. Isoquercitrin at 40 μM and 80 μM was used in vitro. Isoquercitrin increased apoptosis, elevated NLRP3 inflammasome activation-mediated pyroptosis, and promoted ferroptosis in lung cancer cells. NLRP3 knockdown and caspase-1 selective inhibitor VX-765 attenuated isoquercitrin-induced pyroptosis and ferroptosis, but not apoptosis. Furthermore, isoquercitrin accelerated ROS generation, while ROS inhibitor N-acetylcysteine abrogated isoquercitrin-induced apoptosis, NLRP3 related-pyroptosis and ferroptosis. In vivo, isoquercitrin (1 mg/kg and 5 mg/kg) inhibited tumor growth, increased apoptosis, NLRP3-related pyroptosis, ferroptosis and ROS generation in tumors. Taken together, isoquercitrin inhibits lung cancer growth by triggering ROS/NLRP3-mediated pyroptosis and ferroptosis, with ROS also directly inducing apoptosis. This suggests that isoquercitrin might be a potential therapeutic agent for lung cancer. [ABSTRACT FROM AUTHOR]

The mTOR inhibitor everolimus has been approved as a sequential or second‐line therapy for renal cell carcinoma (RCC). However, the development of drug resistance limits its clinical applications. This study aims to address the challenge of everolimus resistance and provide new insights into the treatment of advanced RCC. Here, the cytotoxicity of the DNA methyltransferase 1 (DNMT1) inhibitor SGI‐1027 in inducing cell vacuolation and methuosis is discovered and demonstrated for the first time. Additionally, SGI‐1027 exerts synergistic effects with everolimus, as their combination suppresses the growth, migration, and invasion of renal cancer cells. Mechanistically, apoptosis and GSDME‐dependent pyroptosis triggered by lysosomal membrane permeability (LMP) are observed. The upregulation of GSDME expression and increased lysosomal activity in renal cancer cells provide a therapeutic window for the combination of these two drugs to treat renal cancer. The combination treatment exhibits effective anti‐tumor activity and is well tolerated in a subcutaneous tumor model. Overall, this study validates and reveals the specific cytotoxicity property of SGI‐1027 and its potent synergistic effect with everolimus, offering new insights into advanced RCC therapy and everolimus‐resistance overcoming. [ABSTRACT FROM AUTHOR]

Summary Macrophages, neutrophils, and epithelial cells are pivotal components of the host's immune response against bacterial infections. These cells employ inflammasomes to detect various microbial stimuli during infection, triggering an inflammatory response aimed at eradicating the pathogens. Among these inflammatory responses, pyroptosis, a lytic form of cell death, plays a crucial role in eliminating replicating bacteria and recruiting immune cells to combat the invading pathogen. The immunological function of pyroptosis varies across macrophages, neutrophils, and epithelial cells, aligning with their specific roles within the innate immune system. This review centers on elucidating the role of pyroptosis in resisting gram‐negative bacterial infections, with a particular focus on the mechanisms at play in macrophages, neutrophils, and intestinal epithelial cells. Additionally, we underscore the cell type‐specific roles of pyroptosis in vivo in these contexts during defense. [ABSTRACT FROM AUTHOR]

Inflammation has a pivotal role in the initiation and progression of various cancers, contributing to crucial processes such as metastasis, angiogenesis, cell proliferation and invasion. Moreover, the release of cytokines mediated by inflammation within the tumour microenvironment (TME) has a crucial role in orchestrating these events. The activation of inflammatory caspases, facilitated by the recruitment of caspase‐1, is initiated by the activation of pattern recognition receptors on the immune cell membrane. This activation results in the production of proinflammatory cytokines, including IL‐1β and IL‐18, and participates in diverse biological processes with significant implications. The NOD‐Like Receptor Protein 3 (NLRP3) inflammasome holds a central role in innate immunity and regulates inflammation through releasing IL‐1β and IL‐18. Moreover, it interacts with various cellular compartments. Recently, the mechanisms underlying NLRP3 inflammasome activation have garnered considerable attention. Disruption in NLRP3 inflammasome activation has been associated with a spectrum of inflammatory diseases, encompassing diabetes, enteritis, neurodegenerative diseases, obesity and tumours. The NLRP3 impact on tumorigenesis varies across different cancer types, with contrasting roles observed. For example, colorectal cancer associated with colitis can be suppressed by NLRP3, whereas gastric and skin cancers may be promoted by its activity. This review provides comprehensive insights into the structure, biological characteristics and mechanisms of the NLRP3 inflammasome, with a specific focus on the relationship between NLRP3 and tumour‐related immune responses, and TME. Furthermore, the review explores potential strategies for targeting cancers via NLRP3 inflammasome modulation. This encompasses innovative approaches, including NLRP3‐based nanoparticles, gene‐targeted therapy and immune checkpoint inhibitors. [ABSTRACT FROM AUTHOR]

The regulation of intracellular ionic homeostasis to trigger antigen-specific immune responses has attracted extensive interest in tumor therapy. In this study, we developed a dual-pathway nanoreactor, Au-Cu 2-x Se@ZIF-8@P18 NPs (ACS-Z-P NPs), which targets danger-associated molecular patterns (DAMPs) and releases Zn2+ and reactive oxygen species (ROS) within the tumor microenvironment (TME). Zn2+ released from the metal–organic frameworks (MOFs) was deposited in the cytoplasm, leading to aberrant transcription levels of intracellular zinc-regulated proteins and DNA damage, thereby inducing pyroptosis and immunogenic cell death (ICD) dependent on caspase1/gasdermin D (GSDMD) pathway. Furthermore, upon laser irradiation, ACS-Z-P NPs could break through the limitations of inherent defects of immunosuppression in TME, enhance ROS generation through a Fenton-like reaction cascade, which subsequently triggered the activation of inflammatory vesicles and the release of damage-associated molecular patterns (DAMPs). This cascade effect led to the amplification of pyroptosis and immunogenic cell death (ICD), thereby remodeling the immunosuppressed TME. Consequently, this process improved dendritic cell (DC) antigen presentation and augmented anti-tumor T-cell responses, effectively initiating antigen-specific immune responses and further enhancing pyroptosis and ICD. This study explores the therapeutic properties of these mechanisms in detail. The synthesized Au-Cu 2-x Se@ZIF-8@P18 nanoparticles (ACS-Z-Ps) can effectively enhance the bodyʼs immune response by regulating zinc ion levels within cells. This regulation leads to abnormal levels of zinc-regulated protein transcription and DNA damage, which induces cellular pyroptosis. As a result, antigen presentation to dendritic cells (DCs) is improved, and anti-tumor T-cell responses are enhanced. The ACS-Z-P NPs overcome the limitations of ROS deficiency and immunosuppression in the tumor microenvironment by using H 2 O 2 in the tumor microenvironment through a Fenton-like reaction. This leads to an increased production of ROS and O 2 , remodeling of the immunosuppressed tumor microenvironment, and enhanced induction of cell pyroptosis and immunogenic cell death. ACS-Z-P NPs targeted B16 cells using the photosensitizer P18 in combination with PDT treatment. This approach significantly inhibited the proliferation of B16 cells and effectively inhibited tumor growth. [Display omitted] [ABSTRACT FROM AUTHOR]

Introduction: Osteoarthritis (OA) is a prevalent chronic degenerative disease, marked by a complex interplay of mechanical stress, inflammation, and metabolic imbalances. Recent studies have highlighted the potential of spermidine (SPD), a naturally occurring polyamine known for its antiinflammatory and antioxidant properties, as a promising therapeutic agent for OA. This study delves into the therapeutic efficacy and mechanistic pathways of SPD in mitigating OA symptoms. Methods: Forty Sprague-Dawley rats were randomly assigned to four groups, including the CG (sham operation), model (anterior cruciate ligament transection [ACLT], and treatment (ACLT + two different doses of SPD) groups. In vivo, correlations between OA severity and different interventions were assessed by ELISA, X-rays, CT imaging, histological staining, and immunohistochemistry. In vitro, IL-1β was used to trigger chondrocyte inflammation, and SPD's cytotoxicity was assessed in primary rat chondrocytes. Next, inflammatory markers, extracellular matrix (ECM) proteins, and pathway marker proteins were detected in chondrocytes administered IL-1β alone, SPD, or aryl hydrocarbon receptor (AhR) silencing, by qRT-PCR, Griess reaction, ELISA, Western blot, and immunofluorescence. Morphological alterations and pyroptosis in chondrocytes were examined by transmission electron microscopy (TEM) and flow cytometry. Results: Our research reveals that SPD exerts significant anti-inflammatory and antipyroptotic effects on IL-1β-treated chondrocytes and in anterior cruciate ligament transection (ACLT) rat models of OA, primarily through interaction with the Aryl hydrocarbon receptor (AhR). Specifically, SPD's binding to AhR plays a crucial role in modulating the inflammatory response and cellular pyroptosis by inhibiting both the AhR/NF-κB and NLRP3/caspase-1/GSDMD signaling pathways. Furthermore, the knockdown of AhR was found to negate the beneficial effects of SPD, underscoring the centrality of the AhR pathway in SPD's action mechanism. Additionally, SPD was observed to promote the preservation of cartilage integrity and suppress ECM degradation, further supporting its potential as an effective intervention for OA. Discussion: Collectively, our findings propose SPD as a novel therapeutic approach for OA treatment, targeting the AhR pathway to counteract the disease's progression and highlighting the need for further clinical evaluation to fully establish its therapeutic utility. [ABSTRACT FROM AUTHOR]

Mitochondria are crucial organelles that play a central role in cellular metabolism and programmed cell death in eukaryotic cells. Mitochondrial autophagy (mitophagy) is a selective process where damaged mitochondria are encapsulated and degraded through autophagic mechanisms, ensuring the maintenance of both mitochondrial and cellular homeostasis. Excessive programmed cell death in neurons can result in functional impairments following cerebral ischemia and trauma, as well as in chronic neurodegenerative diseases, leading to irreversible declines in motor and cognitive functions. Neuroinflammation, an inflammatory response of the central nervous system to factors disrupting homeostasis, is a common feature across various neurological events, including ischemic, infectious, traumatic, and neurodegenerative conditions. Emerging research suggests that regulating autophagy may offer a promising therapeutic avenue for treating certain neurological diseases. Furthermore, existing literature indicates that various small molecule autophagy regulators have been tested in animal models and are linked to neurological disease outcomes. This review explores the role of mitophagy in programmed neuronal death and its connection to neuroinflammation. [ABSTRACT FROM AUTHOR]

New and emerging pathogens, such as SARS-CoV2 have highlighted the requirement for threat agnostic therapies. Some antibiotics or antivirals can demonstrate broad-spectrum activity against pathogens in the same family or genus but efficacy can quickly reduce due to their specific mechanism of action and for the ability of the disease causing agent to evolve. This has led to the generation of antimicrobial resistant strains, making infectious diseases more difficult to treat. Alternative approaches therefore need to be considered, which include exploring the utility of Host-Directed Therapies (HDTs). This is a growing area with huge potential but difficulties arise due to the complexity of disease profiles. For example, a HDT given early during infection may not be appropriate or as effective when the disease has become chronic or when a patient is in intensive care. With the growing understanding of immune function, a new generation of HDT for the treatment of disease could allow targeting specific pathways to augment or diminish the host response, dependent upon disease profile, and allow for bespoke therapeutic management plans. This review highlights promising and approved HDTs that can manipulate the immune system throughout the spectrum of disease, in particular to viral and bacterial pathogens, and demonstrates how the advantages of HDT will soon outweigh the potential side effects. [ABSTRACT FROM AUTHOR]

Cisplatin is widely used to treat various solid tumors. However, its toxicity to normal tissues limits its clinical application, particularly due to its ototoxic effects, which can result in hearing loss in patients undergoing chemotherapy. While significant progress has been made in preclinical studies to elucidate the cellular and molecular mechanisms underlying cisplatin-induced ototoxicity (CIO), the precise mechanisms remain unclear. Moreover, the optimal protective agent for preventing or mitigating cisplatin-induced ototoxicity has yet to be identified. This review summarizes the current understanding of the roles of apoptosis, autophagy, ferroptosis, pyroptosis, and protective agents in cisplatin-induced ototoxicity. A deeper understanding of these cell death mechanisms in the inner ear, along with the protective agents, could facilitate the translation of these agents into clinical therapeutics, help identify new therapeutic targets, and provide novel strategies for cisplatin-based cancer treatment. [ABSTRACT FROM AUTHOR]

Introduction: To investigate the protective effects of anisodamine (654-1/654-2) against acute kidney injury (AKI) in LPS-induced septic shock rats and explore its molecular mechanisms. Methods: 56 rats were randomly divided into 8 groups: control, LPS, LPS + 654-1, and LPS + 654-2 (1.25, 2.5 and 5 mg/kg). The model was evaluated by monitoring MAP, HR, and plasma LD levels. ELISA and biochemical assay kits were used to measure the levels of inflammatory cytokines (IL-1ß, IL-6, and TNF-a) and kidney injury markers (BUN and CRE). Additionally, RNA-seq and bioinformatic analysis were performed to explore the mechanism of action of 654-1/654-2, and verification was conducted by western blotting and RT-PCR. Results: 654-1/654-2 significantly restored the levels of MAP, HR, and plasma LD in septic shock rats. Furthermore, 654-1/654-2 (5 mg/kg) effectively ameliorated LPS-induced kidney structural damage and exhibited a dose-dependent reduction in levels of inflammatory cytokines and kidney injury markers. In addition, RNA-seq, WB, and RT-PCR analyses revealed that 654-1/654-2 exerted its effects by inhibiting the expressions of the NF-κB and MAPK pathways and activating the Pi3K/Akt/Bcl-2 signaling pathway, thereby mitigating AKI. Discussion: This study suggested that 654-1/654-2 could alleviate AKI in septic shock rats by improving inflammation invasion and cell apoptosis. Notably, 654-1/654-2 collectively suppressed inflammation response through the p38/JNK/AP-1/NF-κB pathway. Additionally, 654-1 promotes survival signaling via the Pi3K/Akt/Bcl-2 pathway, whereas 654-2 reduces apoptosis through the P53/Bax pathway. These findings provided a theoretical basis for the clinical application of 654-1/654-2 in treating organ damage caused by septic shock. [ABSTRACT FROM AUTHOR]

Introduction: Ischemic stroke (IS) is a serious threat to human life and health, and cerebral ischemia/reperfusion injury (CIRI) exacerbates IS by enhancing neuroinflammation and oxidative stress. Sweet tea (ST) comprises several bioactive components, such as phlorizin, trilobatin, and phloretin, with diverse pharmacological activities. However, it remains uncertain whether ST can confer protection against CIRI. In this study, we aimed to investigate the impact and potential underlying mechanism of ST in the context of CIRI. Methods: CIRI model were established in male sprague dawley (SD) rats. The neurobehavioral assessment, the volume of cerebral infarction and the morphology of neurons were measured to complete the preliminary pharmacodynamic study. The therapeutic targets and pathways of ST on IS were obtained by protein-protein interaction, molecular docking and Metascape database. The predicted results were further verified in vivo. Results: Our results revealed that ST treatment significantly ameliorated brain damage in rats subjected to CIRI by mitigating mitochondrial oxidative stress and neuroinflammation. Additionally, we identified the PI3K/AKT/NF-κB pathway and the NLRP3-mediated pyroptosis axis as crucial processes, with molecular docking suggested direct interactions between the main compounds of ST and NLRP3. Conclusion: ST safeguards against CIRI-induced neuronal loss, neuroinflammation and oxidative stress through the inhibition of the PI3K/AKT/NF-κB pathway and the regulation of NLRP3-mediated pyroptosis. [ABSTRACT FROM AUTHOR]

Postoperative cognitive dysfunction (POCD) poses a significant threat to patients undergoing anesthesia and surgery, particularly elderly patients. It is characterized by diminished cognitive functions post surgery, such as impaired memory and decreased concentration. The potential risk factors for POCD include age, surgical trauma, anesthetic type, and overall health condition; however, the precise mechanisms underlying POCD remain elusive. Recent studies suggest that neuroinflammation might be a primary pathogenic factor. NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) inflammasomes are implicated in exacerbating POCD by promoting the release of inflammatory factors and proteins that initiate pyroptosis, further influencing the disease process. The regulation of NLRP3 inflammasome activity, including its activation and degradation, is tightly controlled through multiple pathways and mechanisms. In addition, autophagy, a protective mechanism, regulates the NLRP3 inflammasome to control the progression of POCD. This review reviews recent findings on the role of the NLRP3 inflammasome in POCD pathogenesis and discusses therapeutic strategies aimed at reducing NLRP3 sources, inhibiting cellular pyroptosis, and enhancing autophagy. [ABSTRACT FROM AUTHOR]

Abstract\nPLAIN LANGUAGE SUMMARYBecause of numerous stress signals, intracellular protein complexes are called inflammasomes. They function as catalysts for the proteolytic transformation of pro-interleukin into the active form of interleukin. Inflammasomes can promote a type of cell death process known as pyroptosis. The NLRP3 inflammasome, comprised of the NLRP3 protein, procaspase-1, and ASC, tightly regulates inflammation. The NLRP3 inflammasome is activated by a variety of stimuli, and several molecular and cellular events, such as ion influx, mitochondrial dysfunction, reactive oxygen species production, and lysosomal damage have been shown to trigger its activation. Inflammation plays a major role in almost all types of human diseases. The NLRP3 inflammasome has been the most widely studied and plays an important pathogenic role in various inflammatory pathologies. This review briefly presents the basic features of NLRP3 inflammasome and their mechanisms of activation and regulation. In addition, recent studies report the role of NLRP3 inflammasome in several diseases have been summarized.Because of numerous stress signals, intracellular protein complexes are called inflammasomes. They function as catalysts for the proteolytic transformation of pro-interleukin into the active form of interleukin. Inflammasomes can promote a type of cell death process known as pyroptosis. The NLRP3 inflammasome, comprised of the NLRP3 protein, procaspase-1, and ASC, tightly regulates inflammation. The NLRP3 inflammasome is activated by a variety of stimuli, and several molecular and cellular events, such as ion influx, mitochondrial dysfunction, reactive oxygen species production, and lysosomal damage, have been shown to trigger its activation. Also, NLRP3 inflammasome plays a role in several different diseases. [ABSTRACT FROM AUTHOR]

Background: The objective of our research was to investigate the specific mechanism of FTO in diabetic kidney disease (DKD) progression. Methods: The DKD model was established with renal tubular epithelial HK-2 cells and mice in vitro and in vivo. The N6-methyladenosine (m6A) content in cells was detected using dot plot assay and the m6A levels of NLRP3 was detected with the MeRIP assay. The mRNA and protein levels were tested with real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) and western blot. The IL-1β and IL-18 levels were assessed with enzyme-linked immunosorbent assay (ELISA). The cell viability was measured by cell counting kit (CCK)-8 assay and cell pyroptosis was determined with Annexin V and propidium iodide (PI) double staining followed by flow cytometry analysis. RNA-binding protein immunoprecipitation (RIP) and dual luciferase reporter assays were conducted to detect the interaction between FTO and NLRP3. m6A levels were detected by Me-RIP assay. The renal injury was measured by observing the renal morphology and urine and blood levels of relevant indicators. Results: The results indicated that high glucose treatment induced HK-2 cell pyroptosis. m6A levels were prominently elevated in high glucose treated HK-2 cells while FTO expression were significantly down-regulated. FTO over-expression promoted cell viability but inhibited pyroptosis of HK-2 cells under high glucose (HG) treatment. Moreover, FTO could inhibit NLRP3 expression. RIP and Me-RIP assays indicated that FTO could bind with NLRP3 and regulate its m6A modification level. Further luciferase assay confirmed that FTO binds with the 233–237 bp region of NLRP3. NLRP3 neutralized the function of FTO in the HG stimulated HK-2 cells. In vivo, the H&E staining showed that FTO over-expression alleviated the kidney injury and suppressed the pyroptosis induced by DKD. Conclusion: We found that FTO could inhibit the DKD progression in vivo and in vitro by regulated the m6A modification of NLRP3. [ABSTRACT FROM AUTHOR]

Introduction: Ischemic stroke (IS) is a serious threat to human life and health, and cerebral ischemia/reperfusion injury (CIRI) exacerbates IS by enhancing neuroinflammation and oxidative stress. Sweet tea (ST) comprises several bioactive components, such as phlorizin, trilobatin, and phloretin, with diverse pharmacological activities. However, it remains uncertain whether ST can confer protection against CIRI. In this study, we aimed to investigate the impact and potential underlying mechanism of ST in the context of CIRI. Methods: CIRI model were established in male sprague dawley (SD) rats. The neurobehavioral assessment, the volume of cerebral infarction and the morphology of neurons were measured to complete the preliminary pharmacodynamic study. The therapeutic targets and pathways of ST on IS were obtained by protein-protein interaction, molecular docking and Metascape database. The predicted results were further verified in vivo. Results: Our results revealed that ST treatment significantly ameliorated brain damage in rats subjected to CIRI by mitigating mitochondrial oxidative stress and neuroinflammation. Additionally, we identified the PI3K/AKT/NF-κB pathway and the NLRP3-mediated pyroptosis axis as crucial processes, with molecular docking suggested direct interactions between the main compounds of ST and NLRP3. Conclusion: ST safeguards against CIRI-induced neuronal loss, neuroinflammation and oxidative stress through the inhibition of the PI3K/AKT/NF-κB pathway and the regulation of NLRP3-mediated pyroptosis. [ABSTRACT FROM AUTHOR]

A paradigm shift in the study of cell death is currently occurring: whereas previously we had always considered that there were "points of no return" in any cell death pathway, we now realize that in many types of active, regulated cell death, this is not the case. We are also learning that cells that "almost die," but nevertheless survive, can transiently take on an altered state, with potential implications for understanding cancer therapies and relapse. In this perspective, we parse the many forms of cell death by analogy to suicide, sabotage, and murder, and consider how cells that might be "instructed" to engage a cell death pathway might nevertheless survive. In this perspective, Douglas Green discusses the many forms of cell death by analogy to suicide, sabotage, and murder and how cells that engage a cell death pathway might still survive. [ABSTRACT FROM AUTHOR]

Caspase-8, a renowned cysteine-aspartic protease within its enzyme family, initially garnered attention for its regulatory role in extrinsic apoptosis. With advancing research, a growing body of evidence has substantiated its involvement in other cell death processes, such as pyroptosis and necroptosis, as well as its modulatory effects on inflammasomes and proinflammatory cytokines. PANoptosis, an emerging concept of cell death, encompasses pyroptosis, apoptosis, and necroptosis, providing insight into the often overlapping cellular mortality observed during disease progression. The activation or deficiency of caspase-8 enzymatic activity is closely linked to PANoptosis, positioning caspase-8 as a key regulator of cell survival or death across various physiological and pathological processes. Aberrant expression of caspase-8 is closely associated with the development and progression of a range of inflammatory diseases, including immune system disorders, neurodegenerative diseases (NDDs), sepsis, and cancer. This paper delves into the regulatory role and impact of caspase-8 in these conditions, aiming to elucidate potential therapeutic strategies for the future intervention. [ABSTRACT FROM AUTHOR]

There is evidence that in infected cells in vitro the meningococcal HrpA/HrpB twopartner secretion system (TPS) mediates the exit of bacteria from the internalization vacuole and the docking of bacteria to the dynein motor resulting in the induction of pyroptosis. In this study we set out to study the role of the HrpA/HrpB TPS in establishing meningitis and activating pyroptotic pathways in an animal model of meningitis using a reference serogroup C meningococcal strain, 93/4286, and an isogenic hrpB knockout mutant, 93/4286WhrpB. Survival experiments confirmed the role of HrpA/HrpB TPS in the invasivemeningococcal disease. In fact, the ability of the hrpB mutant to replicate in brain and spread systemically was impaired in mice infected with hrpBmutant. Furthermore, western blot analysis of brain samples during the infection demonstrated that: i. N. meningitidis activated canonical and noncanonical inflammasome pyroptosis pathways in themouse brain; ii. the activation of caspase-11, caspase-1, and gasdermin-D was markedly reduced in the hrpB mutant; iii. the increase in the amount of IL-1b and IL-18, which are an important end point of pyroptosis, occurs in the brains of mice infected with the wild-type strain 93/4286 and is strongly reduced in those infected with 93/4286WhrpB. In particular, the activation of caspase 11, which is triggered by cytosolic lipopolysaccharide, indicates that during meningococcal infection pyroptosis is induced by intracellular infection after the exit of the bacteria from the internalizing vacuole, a process that is hindered in the hrpBmutant. Overall, these results confirm, in an animal model, that theHrpA/HrpB TPS plays a role in the induction of pyroptosis and suggest a pivotal involvement of pyroptosis in invasive meningococcal disease, paving the way for the use of pyroptosis inhibitors in the adjuvant therapy of the disease. [ABSTRACT FROM AUTHOR]

Objective To investigate the mechanism of astragaloside I, the active constituent of milkvetch root, in inhibiting podocyte injury and improving diabetic kidney disease. Methods According to the body weight, 60 male db/db mice were randomly divided into the model group, astragaloside I low-dose group (10 mg/kg), astragaloside I medium-dose group (20 mg/kg), astragaloside I high-dose group (40 mg/kg), and valsartan group (10 mg/kg), with 12 mice per group. Twelve db/db littermate control dl)/m mice were used as the control group. The drug was administered by gavage for 8 weeks. Transmission electron microscope was used to observe the ultrastructure of the kidney ； immunohistochemistry and Western blotting were used to detect the expression of nephrotic protein (nephrin), a marker of renal podocytes; enzyme-linked immunosorbent assay was used to detect the contents of interleukin-1 β (IL-Ιβ) and interleukin-18 ( IL-18) in the serum of mice; Western blotting was used to detect the protein expressions of NOD-like receptor thermoprotein domain-related protein 3 (NLRP3), cysteinyl aspartate specific proteinase 1 ( Caspase-1), and Gasdermin D ( GSDMD) in kidney tissue. Results Compared with the control group, the glomeruli of the model group showed obvious podocyte loss and foot process fusion ； the protein expression of nephrin was decreased ( P <0.05) ； the contents of υβ and IL-18 in serum were increased ( P <0.05); the protein expressions of NLRP3, Cleaved-Caspase-1, and GSDMD-N were increased ( P<0. 05). Compared with the model group, the renal pathological damage in the astragaloside I administration groups were alleviated; the protein expression of nephrin was increased (P<0. 05) ； the contents of υβ and IL-18 in serum were decreased (P<0. 05)； the protein expressions of NLRP3, Cleaved-Caspase-1, and GSDMD-N were decreased (P <0.05). Conclusion Astragaloside I may play a role in intervening diabetic kidney disease by inhibiting pyroptosis and improving podocyte injury. [ABSTRACT FROM AUTHOR]

As a key molecule for improving cardiovascular diseases, Apelin‐13 was surveyed in this work to explain its actions in controlling inflammation, pyroptosis, and myocardial hypertrophy. First, mouse models with myocardial hypertrophy were established. Then, assessments were made on the pathological variation in the heart of mouse, on the cardiac functions, as well as on the expressions of cardiac hypertrophy markers (β‐MHC, ANP, and BNP), inflammatory factors (TNF‐α, COX2, IL‐6, ICAM‐1, and VCAM‐1), myocardial cell pyroptosis markers (NLRP3, ASC, c‐caspase‐1, and GSDMD‐N), and Hippo pathway proteins (p‐YAP, YAP, LATS1, and p‐LATS1) by HE staining, echocardiography scanning, and western blot tests separately. The expressions of such inflammatory factors as in myocardial tissue were acquired by ELISA. After inducing the phenotype of H9c2 cell hypertrophy by noradrenaline, we used CCK‐8 kits to know about the activity of H9c2 cells treated with Apelin‐13, and performed ɑ‐actinin staining to measure the changes in volumes of such cells. As unraveled through this work, Apelin‐13 refrained the activation of the Hippo pathway, which in turn attenuated the hypertrophy, inflammation, and pyroptosis of myocardial tissue and H9c2 cells. Hence, Apelin‐13 can be considered as a target for hypertension treatment. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Introduction: The presence of hypoxic‐ischemic brain damage (HIBD) in neonates triggers a strong neuroinflammatory reaction. Pyroptosis, a programmed cell death mechanism associated with inflammation, plays a crucial role in HIBD. Pyruvate kinase M2 (PKM2) plays a significant role in connecting metabolic processes and inflammatory responses, but whether it affects hippocampus pyroptosis in HIBD is unclear. The aim of this study is to elucidate the role of PKM2 in HIBD and to propose a novel therapeutic approach for neonatal ischemic‐hypoxic encephalopathy. Methods: In this study, we employed neonatal 7‐day‐old Sprague Dawley rats to establish a model of HIBD using the Rice–Vannucci surgical technique and a hypoxia device. To inhibit the elevation of PKM2, we utilized the PKM2 inhibitor shikonin. The rats were categorized into four groups: Sham, Shikonin, HIBD, and Shikonin + HIBD. Behavioral tests, hematoxylin eosin staining, immunofluorescence staining, ELISA (IL‐1β, IL‐18), and LDH were conducted in each group to evaluate neurological function, hippocampal damage, the occurrence of neuronal pyroptosis, and the neuroinflammation. Western blot was used to assess the expression levels of PKM2, NLRP3, Caspase‐1, Cleaved Caspase‐1, GSDMD, GSDMDN, and IL‐1β. Results: The expression of PKM2 elevated in hippocampal tissues of the HIBD model and the localization of PKM2 in the hippocampus was activated in neurons instead of microglia during the HIBD. Meanwhile, the inhibition of PKM2 improved the behavioral test scores and the body weight of rats, the neuronal damage in the CA1 region of hippocampal tissue was also attenuated. In addition, inhibiting PKM2 alleviated neuronal pyroptosis by decreasing the expression of PKM2, NLRP3, Caspase‐1, Cleaved Caspase‐1, GSDMD, GSDMDN. Furthermore, serum levels of LDH and inflammatory factors IL‐1β and IL‐18 decrease with PKM2 inhibition. Conclusions: Based on these findings, we can conclude that PKM2 plays a crucial role in regulating hippocampal neuronal pyroptosis of HIBD rats via NLRP3/Caspase‐1/GSDMD pathway. Therefore, inhibiting PKM2 could be a promising therapeutic strategy for the treatment of neonatal ischemic‐hypoxic encephalopathy. [ABSTRACT FROM AUTHOR]