OBJECTIVE: To observe the effects of electroacupuncture at the pterygopalatine region on nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)-mediated pyroptosis and inflammatory factors in rats with allergic rhinitis (AR). METHODS: Twenty-four SD rats were randomly divided into a blank group, a model group, an acupuncture group and an electroacupuncture group, 6 rats in each group. Except for the blank group, OVA-induced AR model was established in the remaining groups. In the electroacupuncture group, the rats were treated with electroacupuncture at the bilateral pterygopalatine region, with disperse-dense wave, in frequency of 2 Hz/100 Hz and current of 0.5-1 mA, 15 min each time, once every other day, for 3 times. In the acupuncture group, the rats were treated with acupuncture at bilateral pterygopalatine region simply, without electrical stimulation. The rhinitis symptom score was observed, the pathomorphology of the nasal mucosa was observed by HE staining; the serum levels of OVA-specific immunoglobulin E (OVA-sIgE), interleukin (IL)-4, IL-6 and IL-1β were detected by ELISA; the mRNA expression of NLRP3, apoptosis-associated speck-like protein containing CARD (ASC), cysteinyl aspartate specific proteinase-1 (caspase-1) and IL-18 in the nasal mucosa was detected by real-time PCR; the protein expression of NLRP3, ASC, caspase-1 and IL-18 in the nasal mucosa was detected by Western blot. RESULTS: Compared with the blank group, in the model group, the rhinitis symptom score was increased (P<0.01), the serum levels of OVA-sIgE, IL-4, IL-6 and IL-1β were increased (P<0.05), the nasal mucosa showed pathomorphology of inflammatory infiltration; the mRNA and protein expression of NLRP3, ASC, caspase-1 and IL-18 in the nasal mucosa was increased (P<0.05). Compared with the model group, in the electroacupuncture group, the rhinitis symptom score was reduced (P<0.01), the pathology of the nasal mucosa was improved; the serum levels of OVA-sIgE, IL-4, IL-6 and IL-1β were decreased (P<0.05); the mRNA and protein expression of NLRP3, ASC, caspase-1 and IL-18 in the nasal mucosa was decreased (P<0.05). CONCLUSION Electroacupuncture at the pterygopalatine region can exerting the anti-inflammatory effect by inhibiting NLRP3-mediated pyroptosis and inflammatory factor imbalance, thus alleviate rhinitis symptoms in AR rats.
Animals ; Electroacupuncture ; NLR Family, Pyrin Domain-Containing 3 Protein/immunology* ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic/physiopathology* ; Pyroptosis ; Male ; Acupuncture Points ; Humans ; Female ; Interleukin-1beta/genetics* ; Interleukin-18/immunology* ; Interleukin-6/genetics* ; Caspase 1/immunology*

BACKGROUND: T-cell lymphoblastic lymphoma/acute lymphoblastic leukemia (T-LBL/ALL) is an aggressive form of hematological malignancy associated with poor prognosis in adult patients. Histone deacetylases (HDACs) are aberrantly expressed in T-LBL/ALL and are considered potential therapeutic targets. Here, we investigated the antitumor effect of a novel HDAC inhibitor, chidamide, on T-LBL/ALL. METHODS: HDAC1, HDAC2 and HDAC3 levels in T-LBL/ALL cell lines and patient samples were compared with those in normal controls. Flow cytometry, transmission electron microscopy, and lactate dehydrogenase release assays were conducted in Jurkat and MOLT-4 cells to assess apoptosis and pyroptosis. A specific forkhead box O1 (FOXO1) inhibitor was used to rescue pyroptosis and upregulated gasdermin E (GSDME) expression caused by chidamide treatment. The role of the FOXO1 transcription factor was evaluated by dual-luciferase reporter and chromatin immunoprecipitation assays. The efficacy of chidamide in vivo was evaluated in a xenograft mouse. RESULTS: The expression of HDAC1, HDAC2 and HDAC3 was significantly upregulated in T-LBL/ALL. Cell viability was obviously inhibited after chidamide treatment. Pyroptosis, characterized by cell swelling, pore formation on the plasma membrane and lactate dehydrogenase leakage, was identified as a new mechanism of chidamide treatment. Chidamide triggered pyroptosis through caspase 3 activation and GSDME transcriptional upregulation. Chromatin immunoprecipitation assays confirmed that chidamide led to the increased transcription of GSDME through a more relaxed chromatin structure at the promoter and the upregulation of FOXO1 expression. Moreover, we identified the therapeutic effect of chidamide in vivo . CONCLUSIONS This study suggested that chidamide exerts an antitumor effect on T-LBL/ALL and promotes a more inflammatory form of cell death via the FOXO1/GSDME axis, which provides a novel choice of targeted therapy for patients with T-LBL/ALL.
Humans ; Pyroptosis/drug effects* ; Forkhead Box Protein O1/genetics* ; Aminopyridines/pharmacology* ; Animals ; Mice ; Benzamides/pharmacology* ; Cell Line, Tumor ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/drug therapy* ; Phosphate-Binding Proteins/metabolism* ; Histone Deacetylase Inhibitors/pharmacology* ; Jurkat Cells ; Histone Deacetylases/metabolism* ; Apoptosis/drug effects* ; Gasdermins

BACKGROUND: Knee osteoarthritis (OA) is still challenging to prevent or treat. Enhanced endoplasmic reticulum (ER) stress and increased pyroptosis in chondrocytes may be responsible for cartilage degeneration. This study aims to investigate the effect of ER stress on chondrocyte pyroptosis and the upstream regulatory mechanisms, which have rarely been reported. METHODS: The expression of the histone methyltransferase enhancer of zeste homolog 2 (EZH2), microRNA-142-3p (miR-142-3p), and high mobility group box 1 (HMGB1) and the levels of ER stress, pyroptosis, and metabolic markers in normal and OA chondrocytes were investigated by western blotting, quantitative polymerase chain reaction, immunohistochemistry, fluorescence in situ hybridization, fluorescein amidite-tyrosine-valine-alanine-aspartic acid-fluoromethyl ketone (FAM-YVAD-FMK)/Hoechst 33342/propidium iodide (PI) staining, lactate dehydrogenase (LDH) release assays, and cell viability assessments. The effects of EZH2, miR-142-3p, and HMGB1 on ER stress and pyroptosis and the hierarchical regulatory relationship between them were analyzed by chromatin immunoprecipitation, luciferase reporters, gain/loss-of-function assays, and rescue assays in interleukin (IL)-1β-induced OA chondrocytes. The mechanistic contribution of EZH2, miR-142-3p, and HMGB1 to chondrocyte ER stress and pyroptosis and therapeutic prospects were validated radiologically, histologically, and immunohistochemically in surgically induced OA rats. RESULTS: Increased EZH2 and HMGB1, decreased miR-142-3p, enhanced ER stress, and activated pyroptosis in chondrocytes were associated with OA occurrence and progression. EZH2 and HMGB1 exacerbated and miR-142-3p alleviated ER stress and pyroptosis in OA chondrocytes. EZH2 transcriptionally silenced miR-142-3p via H3K27 trimethylation, and miR-142-3p posttranscriptionally silenced HMGB1 by targeting the 3'-UTR of the HMGB1 gene. Moreover, ER stress mediated the effects of EZH2, miR-142-3p, and HMGB1 on chondrocyte pyroptosis. In vivo experiments mechanistically validated the hierarchical regulatory relationship between EZH2, miR-142-3p, and HMGB1 and their effects on chondrocyte ER stress and pyroptosis. CONCLUSIONS A novel EZH2/miR-142-3p/HMGB1 axis mediates chondrocyte pyroptosis and cartilage degeneration by regulating ER stress in OA, contributing novel mechanistic insights into OA pathogenesis and providing potential targets for future therapeutic research.
Enhancer of Zeste Homolog 2 Protein/genetics* ; Osteoarthritis, Knee/pathology* ; Chondrocytes/metabolism* ; Pyroptosis/physiology* ; HMGB1 Protein/genetics* ; MicroRNAs/metabolism* ; Endoplasmic Reticulum Stress/genetics* ; Humans ; Animals ; Rats ; Male ; Rats, Sprague-Dawley ; Middle Aged

BACKGROUND: The protective effect of mesenchymal stem cells (MSCs) on cardiac ischemia-reperfusion (I/R) injury has been widely reported. Dental pulp-derived mesenchymal stem cells (DP-MSCs) have therapeutic effects on various diseases, including diabetes and cirrhosis. This study aimed to determine the therapeutic effects of DP-MSCs on I/R injury and elucidate the underlying mechanism. METHODS: Myocardial I/R injury model mice were treated with DP-MSCs or a miR-19a-3p mimic. The infarct volume, fibrotic area, pyroptosis, inflammation level, and cardiac function were measured. Cardiomyocytes exposed to hypoxia-reoxygenation were transfected with the miR-19a-3p mimic, miR-19a-3p inhibitor, or negative control. Pyroptosis and protein expression in the interferon regulatory factor 8/mitogen-activated protein kinase (IRF-8/MAPK) pathway were measured. RESULTS: DP-MSCs protected cardiac function in cardiac I/R-injured mice and inhibited cardiomyocyte pyroptosis. The upregulation of miR-19a-3p protected cardiac function, inhibited cardiomyocyte pyroptosis, and inhibited IRF-8/MAPK signaling in cardiac I/R-injured mice. DP-MSCs inhibited cardiomyocyte pyroptosis and the IRF-8/MAPK signaling by upregulating the miR-19a-3p levels in cardiomyocytes injured by I/R. CONCLUSION DP-MSCs protected cardiac function by inhibiting cardiomyocyte pyroptosis through miR-19a-3p under I/R conditions.
Animals ; MicroRNAs/metabolism* ; Pyroptosis/genetics* ; Mesenchymal Stem Cells/metabolism* ; Myocytes, Cardiac/cytology* ; Mice ; Male ; Mice, Inbred C57BL ; Dental Pulp/cytology* ; Myocardial Reperfusion Injury/therapy* ; MAP Kinase Signaling System/physiology*

BACKGROUND: Asthma is a common chronic inflammatory airway disease and intermittent hypoxia is increasingly recognized as a factor that may impact disease progression. The present study investigated whether intermittent hypoxia (IH) could aggravate asthma by promoting hypoxia-inducible factor-1α (HIF-1α)/nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain-containing protein 3 (NLRP3)/interleukin (IL)-1β-dependent pyroptosis and the inflammatory response and further elucidated the underlying molecular mechanisms involved. METHODS: A total of 49 patients diagnosed with severe bronchial asthma and diagnosed by polysomnography were enrolled at Tongji Hospital, Tongji Medical College of Huazhong University of Science and Technology, between January 2022 and December 2022, and their general data and induced sputum were collected. BEAS-2B cells were treated with IL-13 and subjected to IH. An ovalbumin (OVA)-treated mouse model was also used to assess the effects of chronic intermittent hypoxia (CIH) on asthma. Pyroptosis, the inflammatory response, and related signalling pathways were assessed in vivo and in vitro . RESULTS: In this study, as the apnoea and hypopnea index (AHI) increased, the proportion of patients with uncontrolled asthma increased. The proportions of neutrophils and the levels of IL-6, IL-8, HIF-1α and NLRP3 in induced sputum were related to the AHI. NLRP3-mediated pyroptosis, which could be mediated by the HIF-1α signalling pathway, was activated in IL-13 plus IH-treated BEAS-2B cells and in the lungs of OVA/CIH mice. HIF-1α downregulation significantly reduced lung pyroptosis and ameliorated neutrophil inflammation by modulating the NLRP3/IL-1β pathway both in vitro and in vivo . Similarly, pretreatment with LW6, an inhibitor of HIF-1α, effectively blocked the generation of inflammatory cytokines in neutrophils. In addition, administration of the NLRP3 activator nigericin obviously increased lung neutrophil inflammation. CONCLUSIONS Obstructive sleep apnoea-hypopnea syndrome (OSAHS) is a risk factor for asthma exacerbation. IH aggravates neutrophil inflammation in asthma via NLRP3/IL-1β-dependent pyroptosis mediated by the HIF-1α signalling pathway, which should be considered a potential therapeutic target for the treatment of asthma with OSAHS.
NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Humans ; Asthma/metabolism* ; Animals ; Pyroptosis/physiology* ; Hypoxia-Inducible Factor 1, alpha Subunit/metabolism* ; Mice ; Signal Transduction/physiology* ; Male ; Hypoxia/metabolism* ; Female ; Interleukin-1beta/metabolism* ; Adult ; Inflammation/metabolism* ; Middle Aged ; Mice, Inbred C57BL

PANoptosis is a type of programmed cell death regulated by the PANoptosome with key features of pyroptosis, apoptosis and/or necroptosis. As the most complex programmed cell death, PANoptosis emphasizes the compensatory role among multiple programmed cell deaths, and can regulate malignant phenotypes such as proliferation, migration, and invasion of tumor cells through multiple signaling pathways, thus affecting malignant tumor progression. It has been found that PANoptosis plays a dual role in tumor progression and treatment. Therefore, it is clinically important to understand the molecular mechanisms by which PANoptosis affects tumorigenesis, development and progression. This paper reviews the molecular mechanisms of apoptosis, pyroptosis and necroptosis, and discusses the activation and regulation mechanisms of PANoptosis and PANoptosome as well as the research progress on the role of PANoptosis in tumors, aiming to provide new ideas for cancer treatment and prognostic assessment.
Humans ; Neoplasms/physiopathology* ; Pyroptosis/physiology* ; Apoptosis/physiology* ; Necroptosis/physiology* ; Signal Transduction ; Animals

The present study aimed to explore whether hydrogen sulfide (H₂S) improved hypoxic pulmonary hypertension (HPH) in rats by inhibiting aerobic glycolysis-pyroptosis. Male Sprague-Dawley (SD) rats were randomly divided into normal group, normal+NaHS group, hypoxia group, and hypoxia+NaHS group, with 6 rats in each group. The control group rats were placed in a normoxic (21% O₂) environment and received daily intraperitoneal injections of an equal volume of normal saline. The normal+NaHS group rats were placed in a normoxic environment and intraperitoneally injected with 14 μmol/kg NaHS daily. The hypoxia group rats were placed in a hypoxia chamber, and the oxygen controller inside the chamber maintained the oxygen concentration at 9% to 10% by controlling the N₂ flow rate. An equal volume of normal saline was injected intraperitoneally every day. The hypoxia+NaHS group rats were also placed in an hypoxia chamber and intraperitoneally injected with 14 μmol/kg NaHS daily. After the completion of the four-week modeling, the mean pulmonary artery pressure (mPAP) of each group was measured using right heart catheterization technique, and the right ventricular hypertrophy index (RVHI) was weighed and calculated. HE staining was used to observe pathological changes in lung tissue, Masson staining was used to observe fibrosis of lung tissue, and Western blot was used to detect protein expression levels of hexokinase 2 (HK2), pyruvate dehydrogenase (PDH), pyruvate kinase isozyme type M2 (PKM2), nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), GSDMD-N-terminal domain (GSDMD-N), Caspase-1, interleukin-1β (IL-1β) and IL-18 in lung tissue. ELISA was used to detect contents of IL-1β and IL-18 in lung tissue. The results showed that, compared with the normal control group, there were no significant changes in all indexes in the normal+NaHS group, while the hypoxia group exhibited significantly increased mPAP and RVHI, thickened pulmonary vascular wall, narrowed lumen, increased collagen fibers, up-regulated expression levels of aerobic glycolysis-related proteins (HK2 and PKM2), up-regulated expression levels of pyroptosis-related proteins (NLRP3, GSDMD-N, Caspase-1, IL-1β, and IL-18), and increased contents of IL-1β and IL-18. These changes of the above indexes in the hypoxia group were significantly reversed by NaHS. These results suggest that H₂S can improve rat HPH by inhibiting aerobic glycolysis-pyroptosis.
Animals ; Rats, Sprague-Dawley ; Male ; Hypertension, Pulmonary/metabolism* ; Glycolysis/drug effects* ; Hydrogen Sulfide/therapeutic use* ; Hypoxia/complications* ; Rats ; Pyroptosis/drug effects*

OBJECTIVES: To investigate the therapeutic mechanism of nodakenin for Crohn's disease (CD)-like colitis in mice. METHODS: Using a colonic organoid model with lipopolysaccharide (LPS)- and ATP-induced pyroptosis, we investigated the effects of nodakenin on pyroptosis, intestinal barrier function and inflammatory response by detecting key pyroptosis-regulating factors and assessing changes in permeability and pro-inflammatory factors. In a mouse model of 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced CD-like colitis, the therapeutic effect of nodakenin was evaluated by measuring changes in body weight, DAI score, colonic histopathologies, inflammation score, intestinal barrier function and intestinal epithelial cell pyroptosis. The mechanism of nodakenin protection against pyroptosis of intestinal epithelial cells was explored using network pharmacology analysis and in vivo and in vitro experiments. RESULTS: In LPS- and ATP-induced colonic organoids, treatment with nodakenin significantly inhibited the expressions of NLRP3, GSDMD-N, cleaved caspase-1 and caspase-11, improved intestinal FITC-dextran (FD4, 4000) permeability, and decreased the levels of IL-1β and IL-18. In the mouse model of TNBS-induced colitis, nodakenin treatment significantly alleviated weight loss, reduced DAI score, inflammatory cell infiltration and inflammation score, and decreased serum FD4 and I-FABP levels and bacteria translocation to the mesenteric lymph nodes, spleen and liver. The mice with nodakenin treatment had also lowered expressions of NLRP3, GSDMD-N, cleaved caspase-1 and caspase-11 in the intestinal mucosa. Network pharmacology analysis suggested that the inhibitory effect of nodakenin on colitis was associated with the PI3K/Akt pathway. In both the colonic organoid model and mouse models of colitis, nodakenin effectively inhibited the activation of the PI3K/Akt pathway, and the application of IGF-1, a PI3K/Akt pathway activator, strongly attenuated the protective effect of nodakenin against intestinal epithelial cell pyroptosis and intestinal barrier dysfunction. CONCLUSIONS Nodakenin protects intestinal barrier function and alleviates CD-like colitis in mice at least partly by inhibiting PI3K/Akt signaling to reduce intestinal epithelial cell pyroptosis.
Animals ; Pyroptosis/drug effects* ; Mice ; Trinitrobenzenesulfonic Acid ; Colitis/drug therapy* ; Epithelial Cells/drug effects* ; Intestinal Mucosa/cytology* ; Disease Models, Animal ; Coumarins/pharmacology* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Crohn Disease/drug therapy*

OBJECTIVES: To investigate the effect of amentoflavone (AF) for alleviating lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and inhibiting NLRP3/ASC/Caspase-1 axis-mediated pyroptosis. METHODS: Female BALB/c mice were randomly divided into control group, LPS group, and AF treatment groups at low, moderate and high doses (n=12). ALI models were established by tracheal LPS instillation, and in AF treatment groups, AF was administered by gavage 30 min before LPS instillation. Six hours after LPS instillation, the mice were euthanized for examining lung tissue histopathological changes, protein levels in BALF, and MPO levels in the lung tissue. In the in vitro experiment, RAW264.7 cells were pretreated with AF, AC (a pyroptosis inhibitor), or their combination for 2 h before stimulation with LPS and ATP. The changes in cell proliferation and viability were detected using CCK-8 assay, and IL-1β, IL-6, IL-18, and TNF-α levels were determined with ELISA. Immunohistochemistry, immunofluorescence assay, and immunoblotting were used to detect the protein levels of NLRP3, ASC, cleaved caspase-1, and GSDMD N in rat lung tissues and the treated cells. RESULTS: In mice with LPS exposure, AF treatment significantly improved lung pathologies and edema, reduced protein levels in BALF and pulmonary MPO level, inhibited the high expression of NLRP3/ASC/Aspase-1 axis, reduced the expression of GSDMD N, and lowered the release of IL-1β, IL-6, IL-18, and TNF‑α. In RAW264.7 cells with LPS and ATP stimulation, AF pretreatment effectively reduced cell death, inhibited activation of the NLRP3/ASC/Aspase-1 axis, and reduced GSDMD N expression and the inflammatory factors. The pyroptosis inhibitor showed a similar effect to AF, and their combination produced more pronounced effects in RAW264.7 cells. CONCLUSIONS Amentoflavone can alleviate ALI in mice possibly by inhibiting NLRP3/ASC/Caspase-1 axis-mediated cell pyroptosis.
Animals ; Pyroptosis/drug effects* ; Acute Lung Injury/pathology* ; Mice ; Mice, Inbred BALB C ; Female ; Lipopolysaccharides ; Biflavonoids/pharmacology* ; RAW 264.7 Cells ; NLR Family, Pyrin Domain-Containing 3 Protein ; Caspase 1/metabolism* ; Lung

OBJECTIVES: To study the mechanism mediating the protective effect of asiaticoside (AS) against myocardial ischemia-reperfusion injury (MIRI) in rats. METHODS: Fifty SD rats were randomized into sham-operated group, MIRI model group and AS treatment group. AS treatment was administered at low, moderate and high doses by daily gavage for 2 weeks before MIRI modeling (n=10). Serum levels of lactate dehydrogenase (LDH), creatine kinase isoenzyme (CK-MB), interleukin-18 (IL-18) and IL-1β, the volume of myocardial infarction and ischemia, and myocardial pathologies of the rats were determined or observed. The protein expression levels of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18 in the myocardial tissues were detected using Western blotting. The changes in the expression levels of these proteins were also detected in H9C2 cells with AS pretreatment prior to hypoxia-reoxygenation (H/R) injury. RESULTS: The rats models of MIRI exhibited significant myocardial infarction and ischemia with increased serum levels of LDH and CK-MB and myocardial expressions of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18. AS pretreatment effectively reduced myocardial infarction volume in the rat models and significantly reduced serum LDH and CK-MB levels and the protein levels in the myocardial tissue in a dose-dependent manner. In the H9C2 cell model of H/R injury, AS pretreatment significantly suppressed the elevation of the protein expressions of NLRP3, ASC, caspase-1, GSDMD, GSDMD-N, IL-1β and IL-18. Molecular docking studies showed that AS had a strong binding affinity with NLRP3. CONCLUSIONS Asiaticoside can alleviate MIRI in rats possibly by inhibiting NLRP3 inflammasome-mediated pyroptosis.
Animals ; Myocardial Reperfusion Injury/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Pyroptosis/drug effects* ; Rats, Sprague-Dawley ; Rats ; Inflammasomes/metabolism* ; Triterpenes/pharmacology* ; Interleukin-18/metabolism* ; Male ; Interleukin-1beta/metabolism* ; Caspase 1/metabolism*