OBJECTIVES: To investigate the effect of high glucose on macrophage polarization and the role of immune-responsive gene 1 (IRG1) in mediating its effect. METHODS: RAW264.7 cells were transfected with IRG1-overexpressing plasmid or IRG1 siRNA via electroporation and cultured in either normal or high glucose for 72 h to observe the changes in cell viability and morphology using CCK-8 assay and phase contrast microscopy. The protein levels of IRG1, iNOS, Arg-1, IL-1β and IL-10 in the treated cells were detected with Western blotting, and the fluorescence intensities of iNOS and Arg-1 were detected using immunofluorescence assay. The protein levels of IL-1β and IL-10 in the culture medium were determined with ELISA. RESULTS: High glucose exposure significantly reduced IRG1 and Arg-1 expressions, increased iNOS and IL-1β expressions and IL-1β secretion, and decreased IL-10 level in RAW264.7 cells. Transfection with the IRG1-overexpressing plasmid provided the cells with obvious resistance to high glucose-induced changes in iNOS, Arg-1, IL-1β and IL-10, whereas IRG1 knockdown further enhanced the effects of high glucose exposure on Arg-1 expression and the expression and secretion of IL-10. CONCLUSIONS High glucose promotes M1 polarization of the macrophages possibly through a mechanism to inhibit the expression of IRG1 protein, thus leading to chronic inflammatory response.
Animals ; Mice ; Macrophages/drug effects* ; Glucose/pharmacology* ; Interleukin-10/metabolism* ; Nitric Oxide Synthase Type II/metabolism* ; RAW 264.7 Cells ; Interleukin-1beta/metabolism* ; Arginase/metabolism* ; RNA, Small Interfering/genetics* ; Transfection ; Inflammation

OBJECTIVES: To study the therapeutic mechanism of Tuihuang Mixture against cholestasis. METHODS: Forty-eight Wistar rats were randomized equally into blank group, model group, ursodeoxycholic acid group and Tuihuang Mixture group. Except for those in the blank group, all the rats were given α‑naphthylisothiocyanate (ANIT) to establish rat models of cholestasis, followed by treatments with indicated drugs or distilled water. Serum levels of ALT, AST, ALP, γ-GT, TBA and TBIL of the rats were determined, and hepatic expressions IL-1β, IL-18, FXR, NLRP3, ASC, Caspase-1 and GSDMD were detected using q-PCR, ELISA or Western blotting. Histopathological changes of the liver tissues were observed using HE staining. RESULTS: The rat models of cholestasis had significantly increased serum levels of ALT, AST, ALP, γ-GT, TBA and TBIL with increased mRNA and protein expressions of IL-1β and IL-18, decreased protein and mRNA expressions of FXR, and increased protein expressions of NLRP3 and Caspase-1 and mRNA expressions of NLRP3, ASC, Caspase-1 and GSDMD in the liver tissue, showing also irregular arrangement of liver cells, proliferation of bile duct epithelial cells and inflammatory cells infiltration. Treatment of the rat models with Tuihuang Mixture significantly decreased serum levels of ALT, AST, ALP, γ-GT, TBA and TBIL, lowered IL-1β and IL-18 and increased FXR protein and mRNA expressions, and reduced NLRP3, ASC, Caspase-1 and GSDMD proteins and NLRP3, ASC and Caspase-1 mRNA expressions in the liver tissue. Tuihuang Mixture also significantly alleviated hepatocyte injury, bile duct epithelial cell proliferation and inflammatory cell infiltration in the liver of the rat models. CONCLUSIONS Tuihuang Mixture can effectively improve cholestasis in rats possibly by inhibiting NLRP3 inflammatosome-mediated pyroptosis via regulating FXR.
Animals ; NLR Family, Pyrin Domain-Containing 3 Protein ; Rats ; Receptors, Cytoplasmic and Nuclear/metabolism* ; Cholestasis/drug therapy* ; Rats, Wistar ; Inflammasomes/metabolism* ; 1-Naphthylisothiocyanate ; Drugs, Chinese Herbal/therapeutic use* ; Male ; Interleukin-18/metabolism* ; Caspase 1/metabolism* ; Interleukin-1beta/metabolism* ; Liver/metabolism*

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*

OBJECTIVES: To explore the mechanism through which moxibustion promotes endometrial repair in rats with in thin endometrium (TE). METHODS: Female SD rats were randomized into control group, 95% anhydrous ethanol-induced TE model group and moxibustion (at "Guan Yuan") group. High-throughput sequencing was used to identify the target genes of TE, and the targeting relationship between miR-223-3p and NLRP3 was verified using a dual luciferase assay. Histopathological of rat uterus was observed with HE staining, and expressions of miR-223-3p and NLRP3 were detected using RT-qPCR; serum levels of IL-1β and IL-18 of the rats were detected using ELISA, and protein expressions of NLRP3, ASC, caspase-1 and GSDMD in the uterus were detected with Western blotting. The pregnancies of the rats after treatment were counted. RESULTS: Enrichment analysis of the differential genes suggested up-regulated inflammatory response in TE, and dual luciferase assay verified targeted inhibition of NLRP3 expression by miR-223-3p. The rat models of TE had significantly decreased endometrial thickness and reduced endometrial glands and blood vessels with enhanced mRNA expression of NLRP3, increased serum levels of IL-1β and IL-18, up-regulated protein expressions of NLRP3, ASC, caspase-1 and GSDMD, lowered pregnancy rates on both the affected and unaffected sides and the overall number of pregnancies. Treatment of the rat models with mo-xibustion obviously increased the endometrial thickness and the density of glands and blood vessels, up-regulated miR-223-3p expression, lowered serum IL-1β and IL-18 levels and the protein expressions of NLRP3, ASC, caspase-1 and GSDMD, and significantly increased the number of pregnancies. CONCLUSIONS Moxibustion at "Guan Yuan" acupoint up-regulates the expression of miR-223-3p, which results in targeted inhibition of NLRP3 to suppress pyroptosis and promote endometrial repair in rat models of TE.
Animals ; Female ; MicroRNAs/genetics* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Endometrium/pathology* ; Rats, Sprague-Dawley ; Rats ; Moxibustion ; Pyroptosis ; Up-Regulation ; Interleukin-1beta/metabolism* ; Interleukin-18 ; Caspase 1/metabolism*

OBJECTIVES: To investigate the therapeutic effect of electroacupuncture (EA) at Zusanli (ST36) acupoint on hyperlipidemia in mice and explore the underlying mechanisms. METHODS: Thirty C57BL/6J mice were equally randomized into normal diet group, high-fat diet (HFD) group, and EA group. The changes in blood lipids and serum malondialdehyde (MDA) content of the mice were evaluated, and histopathological changes and lipid accumulation in the liver were observed using Oil red O staining (ORO). The expressions of NLRP3, TLR4, and IL-1β proteins in the colon tissues were detected with Western blotting, and gut microbiota changes were analyzed using 16S rDNA sequencing. RESULTS: In mice with HFD feeding, 16 weeks of EA treatment significantly lowered body weight and serum TC, TG, LDL-C and MDA levels, obviously reduced lipid accumulation in the liver, and ameliorated HFD-induced elevations of protein expressions of NLRP3, TLR4, and IL-1β. 16S rRNA sequencing revealed that EA significantly altered gut microbiota composition, and increased the diversity and relative abundance of beneficial bacterial groups such as Muribaculaceae and Lachnospiraceae NK4A136_group. CONCLUSIONS Electroacupuncture at ST36 alleviates blood lipid disorders in hyperlipidemic mice possibly by improving intestinal microbiota structure, promoting degradation of high-caloric carbohydrates, cholesterol lipid metabolism and intestinal mucosa repair, and reducing toxin leakage, lipid peroxides, and liver fat deposition.
Animals ; Electroacupuncture ; Gastrointestinal Microbiome ; Hyperlipidemias/blood* ; Mice, Inbred C57BL ; Mice ; Diet, High-Fat ; Toll-Like Receptor 4/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein ; Acupuncture Points ; Male ; Lipids/blood* ; Interleukin-1beta/metabolism* ; Liver/metabolism*

OBJECTIVES: To investigate the effect of avitinib for suppressing NLRP3 inflammasome activation and alleviating septic shock and explore the underlying mechanism. METHODS: Mouse bone marrow-derived macrophages (BMDM), human monocytic leukemia cell line THP-1, and peripheral blood mononuclear cells (PBMC) isolated from healthy volunteers were pre-treated with avitinib, followed by activation of the canonical NLRP3 inflammasome using agonists including nigericin, monosodium urate (MSU) crystals, or adenosine triphosphate (ATP). Non-canonical NLRP3 inflammasome activation was induced via intracellular transfection of lipopolysaccharide (LPS). Western blotting was used to detect the secretory protein markers of NLRP3 inflammasome activation and assess pyroptosis, and the levels of inflammatory cytokines in cell culture supernatant were determined with ELISA. In a mouse model of LPS-induced septic shock, the effect of avitinib treatment on the levels of inflammatory cytokines in serum and peritoneal lavage fluid were examined with ELISA, and survival curves of the mice were plotted using the Kaplan-Meier method. RESULTS: Avitinib significantly inhibited NLRP3 inflammasome activation in multiple cell types, and dose-dependently reduced IL-1β secretion and caspase-1 cleavage while suppressing GSDMD-mediated pyroptosis without obviously affecting IL-6 or TNF-α levels. In the mouse models of LPS-induced septic shock, avitinib significantly lowered IL-1β levels in serum and peritoneal fluid and extended survival time of the mice. CONCLUSIONS Avitinib suppresses NLRP3 inflammasome activation and alleviates septic shock in mice.
Animals ; Shock, Septic/metabolism* ; Mice ; NLR Family, Pyrin Domain-Containing 3 Protein ; Inflammasomes/drug effects* ; Humans ; Macrophages/metabolism* ; Interleukin-1beta/metabolism* ; Lipopolysaccharides

OBJECTIVES: To investigate the regulatory role of the NLRP3 signaling pathway in hepatocyte pyroptosis in nonalcoholic steatohepatitis (NASH) under hypoxia. METHODS: Twenty-four male C57BL/6 mice were randomized equally into hypoxic control (A), hypoxic NASH model (B), hypoxic NASH+NLRP3 inhibitor (C), and hypoxic NASH+caspase-1 inhibitor (D) groups. In groups B-D, the mice were fed a methionine choline-deficient (MCD) diet under hypoxic conditions (to simulate a 5000 m altitude) for 6 weeks; the mice in groups C and D received intraperitoneal injections of the respective inhibitors every other day. RESULTS: Compared with those in group A, the mice in group B showed significantly elevated serum levels of FBG, TC, TG, ALT and AST, increased liver lipid content, inflammatory cell infiltration and collagen fiber deposition, and enhanced hepatic expressions of NLRP3, caspase-1, IL-1β and GSDMD proteins, with obvious swelling, cristae breakage, vacuolization, and outer membrane disruption of the mitochondria, ribosome loss in the cytoplasm, destruction of the nuclear membrane, and pathological changes of the rough endoplasmic reticulum. Treatment with NLRP3 inhibitor and caspase-1 inhibitor both significantly lowered serum levels of TC, TG, ALT and AST (but without significantly affecting FBG) in the mouse models, and reduced liver lipid content, inflammatory cell infiltration, collagen deposition, and expression levels of NLRP3, caspase-1, GSDMD and IL-1β. The treatments also significantly improved pathological changes in the mitochondria, ribosomes and endoplasmic reticulum in liver tissues of the mice. CONCLUSIONS NLRP3 signaling pathway plays a key role in promoting hepatocyte pyroptosis in NASH mice under hypoxic condition, and inhibiting this pathway can effectively reduce liver inflammation, suggesting its potential as a therapeutic target for NASH treatment.
Animals ; Non-alcoholic Fatty Liver Disease/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Pyroptosis ; Mice, Inbred C57BL ; Male ; Hepatocytes/pathology* ; Signal Transduction ; Mice ; Hypoxia/metabolism* ; Caspase 1/metabolism* ; Interleukin-1beta/metabolism* ; Liver/metabolism*

OBJECTIVES: To assess the therapeutic effect of aucubin in mice with knee osteoarthritis (KOA) and investigate the underlying mechanism. METHODS: Sixty C57BL/6J mice were randomized equally into sham operation group, KOA model group, glucosamine (positive control) treatment group, and low-, medium-, and high-dose aucubin treatment groups (2, 4, and 8 mg/kg, respectively). KOA mouse models were established by transection of the anterior cruciate ligament (ACL), and the treatment was initiated on day 1 postoperatively and administered weekly for 8 weeks. Safranin O-fast green staining, immunohistochemistry, and microCT were used to evaluate the changes in cartilage pathology, inflammatory protein expression, and subchondral bone volume fraction (BV/TV). The expression levesl of COL2, SOX9, p-P65, IL-1β and MMP13 proteins in the cartilage tissues were detected using Western blotting. In a chondrocyte model with IL-1β treatment for mimicking KOA, the effect of aucubin on chondrogenic differentiation was observed with Alcian blue and Safranin O staining, and cellular COL2, SOX9 and TNF‑α mRNA expressions were detected with RT-qPCR. RESULTS: Compared with those in the model group, the mouse models receiving aucubin treatment showed significantly upregulated COL2 and SOX9 protein levels and downregulated p-P65, IL-1β and MMP13 expressions in the cartilage tissues. In the IL-1β-induced chondrocyte model, aucubin treatment significantly upregulated the mRNA expressions of SOX9 and COL2 but lowered the mRNA expression of TNF-α. Alcian blue and Safranin O staining confirmed that aucubin promoted the synthesis of cartilage extracellular matrix and enhanced chondrogenic differentiation of the cells. CONCLUSIONS Aucubin can effectively alleviate KOA in mice by inhibiting NF‑κB-mediated cartilage inflammation, promoting cartilage matrix synthesis, and improving subchondral bone microstructure.
Animals ; Mice, Inbred C57BL ; Mice ; Osteoarthritis, Knee/drug therapy* ; Signal Transduction/drug effects* ; NF-kappa B/metabolism* ; Iridoid Glucosides/therapeutic use* ; SOX9 Transcription Factor/metabolism* ; Chondrocytes/drug effects* ; Male ; Interleukin-1beta/metabolism* ; Matrix Metalloproteinase 13/metabolism* ; Collagen Type II/metabolism* ; Disease Models, Animal

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

BACKGROUND: Osteoarthritis (OA) is a prevalent joint disorder that significantly impairs quality of life among elderly individuals because of chronic pain and physical disability. As the global burden of OA continues to rise, novel therapeutic strategies are urgently needed. Kaempferide (KA), a flavonoid derived from traditional Chinese herbal medicine, is known for its anti-inflammatory properties. However, the effect of KA on the progression of OA has not been well investigated. This study aimed to explore the therapeutic potential of KA in an OA model and investigate the underlying mechanisms via transcriptomic sequencing. METHODS: An in vitro OA model was established using SW1353 cells treated with interleukin-1 beta (IL-1β) and different concentrations of KA (30, 60, or 90 μmol/L) for 24 h. The anti-inflammatory effects of KA were assessed using quantitative real-time polymerase chain reaction (qRT-PCR), enzyme-linked immunosorbent assay (ELISA), and Western blotting. In vivo , a papain-induced OA rat model was used to evaluate the therapeutic effects of KA through histological and behavioral analyses. Transcriptomic sequencing was performed to explore the differentially expressed genes (DEGs) and related signaling pathways. Statistical analysis was conducted using one-way analysis of variance. RESULTS: KA significantly increased cell viability in the OA chondrocyte model and downregulated the expression of inflammatory cytokines and cartilage degradation markers, with the greatest reduction observed at 90 μmol/L. In vivo , KA treatment mitigated cartilage degradation and improved gait behavior in OA rats. Transcriptomic analysis revealed substantial modulation of DEGs, implicating the hypoxia-inducible factor-1 (HIF-1) signaling pathway as a key mechanism. Further blocking and rescue experiments revealed that KA regulated key molecules within the HIF-1 pathway, specifically interferon-gamma (IFN-γ) and hypoxia-inducible factor 1-alpha (HIF-1α), confirming their critical roles in mediating the therapeutic effects of KA. CONCLUSION KA inhibited the progression of OA by targeting the HIF-1 signaling pathway, reducing inflammation, and cartilage degradation.
Animals ; Osteoarthritis/metabolism* ; Signal Transduction/drug effects* ; Rats ; Rats, Sprague-Dawley ; Humans ; Male ; Hypoxia-Inducible Factor 1/metabolism* ; Interleukin-1beta