OBJECTIVE: To investigate the effect of aquaporin 5 (AQP5) on Toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88)/nuclear factor κB (NF-κB) signaling pathway in Sjögren syndrome (SS) rats. METHODS: The SS gene expression data sets GSE406611 and GSE84844 were extracted from the Gene Expression Omnibus (GEO), and the AQP5 mRNA expression was analyzed by R software. The rat SS model was constructed. The successfully modeled rats were divided into SS group, SS+NC group, and SS+pc group, 10 rats in each group; and 10 rats were set as Normal group. The rats in the SS+NC group were injected with 10 μg of rno-pcDNA3.1-AQP5-NC at the submandibular gland, subcutaneously every day for 28 days. The rats in the SS+pc group were injected with 10 μg of rno-pcDNA3.1-AQP5 at the submandibular gland, subcutaneously every day for 28 days. The enzyme-linked immunosorbent assay (ELISA) kit was used to detect the content of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in the serum. High-throughput sequencing was used to identify the target genes. Quantitative real-time PCR (qPCR) and Western blot were used to detect the mRNA and protein expressions of AQP5, TLR4, MyD88, and NF-κB in the rat submandibular gland tissue. RESULTS: In the SS dataset GSE406611 and GSE84844, the mRNA expression of AQP5 in SS was significantly reduced. Compared with the Normal group, the content of TNF-α and IL-1β in the serum, the mRNA and protein expressions of TLR4, MyD88, and NF-κB in the SS group were significantly increased, the mRNA and protein expressions of AQP5 were significantly decreased. After overexpression of AQP5, the content of TNF-α and IL-1β in the serum, the mRNA and protein expressions of TLR4, MyD88, and NF-κB in the SS+pc group were significantly decreased, the mRNA and protein expressions of AQP5 were significantly increased. The differences were statistically significant (all P < 0.05). CONCLUSION The expression of AQP5 is involved in the progression of SS. Increasing the expression of AQP5 can significantly inhibit inflammatory stress and reduce the pathological damage of submandibular gland tissue. This may be related to the inhibition of TLR4/MyD88/NF-κB conduction.
Animals ; Toll-Like Receptor 4/genetics* ; Myeloid Differentiation Factor 88/genetics* ; Aquaporin 5/metabolism* ; Sjogren's Syndrome/genetics* ; Signal Transduction ; NF-kappa B/metabolism* ; Rats ; Rats, Sprague-Dawley ; Interleukin-1beta/metabolism* ; Female

OBJECTIVE: To investigate the inhibitory effect of Tanreqing Injection (TRQ) on the activation of nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 (NLRP3) inflammasome in macrophages infected with influenza A virus and the underlying mechanism based on mitophagy pathway. METHODS: The inflammatory model of murine macrophage J774A.1 induced by influenza A virus [strain A/Puerto Rico/8/1934 (H1N1), PR8] was constructed and treated by TRQ, while the mitochondria-targeted antioxidant Mito-TEMPO and autophagy specific inhibitor 3-methyladenine (3-MA) were used as controls to intensively study the anti-inflammatory mechanism of TRQ based on mitophagy-mitochondrial reactive oxygen species (mtROS)-NLRP3 inflammasome pathway. The levels of NLRP3, Caspase-1 p20, microtubule-associated protein 1 light chain 3 II (LC3II) and P62 proteins were measured by Western blot. The release of interleukin-1β (IL-1β) was tested by enzyme linked immunosorbent assay, the mtROS level was detected by flow cytometry, and the immunofluorescence and co-localization of LC3 and mitochondria were observed under confocal laser scanning microscopy. RESULTS: Similar to the effect of Mito-TEMPO and contrary to the results of 3-MA treatment, TRQ could significantly reduce the expressions of NLRP3, Caspase-1 p20, and autophagy adaptor P62, promote the expression of autophagy marker LC3II, enhance the mitochondrial fluorescence intensity, and inhibit the release of mtROS and IL-1β (all P<0.01). Moreover, LC3 was co-localized with mitochondria, confirming the type of mitophagy. CONCLUSION TRQ could reduce the level of mtROS by promoting mitophagy in macrophages infected with influenza A virus, thus inhibiting the activation of NLRP3 inflammasome and the release of IL-1β, and attenuating the inflammatory response.
Mitophagy/drug effects* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Animals ; Macrophages/virology* ; Inflammasomes/drug effects* ; Drugs, Chinese Herbal/pharmacology* ; Mice ; Mitochondria/metabolism* ; Reactive Oxygen Species/metabolism* ; Influenza A virus/physiology* ; Interleukin-1beta/metabolism* ; Cell Line ; Injections

OBJECTIVE: To evaluate the protective effects of resveratrol against acute lung injury (ALI) and investigate the potential mechanisms underlying the reactive oxygen species (ROS)-triggered thioredoxin-interacting protein (TXNIP)/NOD-, LRR- and pyrin domain-containing protein 3 (NLRP3) pathway. METHODS: C57BL/6 mice and J774A.1 cells were selected as the research subjects. Thirty Mice were randomly divided into 5 groups of 6 in each group: control with 0.9% saline, 5 mg/kg lipopolysaccharide (LPS) 24 h, 25 mg/kg resveratrol + 5 mg/kg LPS, 100 mg/kg resveratrol + 5 mg/kg LPS, and 4 mg/kg NLRP3 inhibitor CY-09 + 5 mg/kg LPS. For cell stimulation, cells were pretreated with 5 and 20 µmol/L resveratrol for 2 h, and stimulated with or without 1 µg/mL LPS and 3 mmol/L ATP for 2 h. The antioxidant N-acetyl-L-cysteine (NAC, 2 µmol/L) was used as the positive control group. Hematoxylin and eosin staining was used to evaluate the degree of lung LPS-induced tissue damage, and enzyme-linked immunosorbent assay was used to evaluate the contents of interleukin-1 β (IL-1 β) and IL-18 in the serum and cell supernatant. ROS and malondialdehyde (MDA) levels in the lung tissue were detected using the corresponding kits. Western blotting was used to detect the expressions of TXNIP, high-mobility group box 1 (HMGB1), NLRP3, as well as cysteine-aspartic acid protease 1 (caspase-1) and gasdermin D (GSDMD) along with their cleaved forms in lung tissue. Additionally, reverse transcription quantitative polymerase chain reaction was performed to analyze the expression of related inflammatory cytokines. ROS content was detected using flow cytometry and confocal laser microscopy. Mitochondrial morphological changes were observed using transmission electron microscopy, and HMGB1 expression was detected using immunofluorescence. RESULTS: Resveratrol significantly alleviated LPS-induced lung damage with reduced inflammation, interstitial edema, and leukocyte infiltration (P<0.01). It also decreased serum levels of IL-1 β and IL-18 (P<0.05), while downregulating the expressions of NLRP3, IL-6, and other inflammatory markers at both the protein and mRNA levels (P<0.05). Notably, the higher dose (100 mg/kg) demonstrated a better effect than the lower dose (25 mg/kg). In macrophages, resveratrol reduced IL-1 β and IL-18 following LPS and ATP stimulation, suppressed HMGB1 translocation, and inhibited formation and activation of the NLRP3 inflammasome (P<0.05 or P<0.01). These anti-inflammatory effects were mediated through the suppression ROS accumulation (P<0.01) and mitochondrial dysfunction. Transmission electron microscopy revealed that resveratrol preserved mitochondrial structure, preventing the mitochondrial damage seen in LPS-treated groups (P<0.01). The expressions of cleaved caspase-1, cleaved GSDMD, and cytoplasmic HMGB1 were all reduced following resveratrol treatment (P<0.01). Moreover, resveratrol inhibited dissociation of TXNIP from thioredoxin, blocking subsequent activation of NLRP3 and downstream inflammatory cytokines (P<0.01). Similarly, the higher concentration of resveratrol (20 µ mol/L) exhibited superior efficacy in vitro. CONCLUSION Resveratrol can reduce the inflammatory response following ALI and inhibit the activation of NLRP3 inflammasome and the level of HMGB1 in the cytoplasm by inhibiting ROS overproduction.
Acute Lung Injury/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Animals ; Resveratrol/pharmacology* ; Reactive Oxygen Species/metabolism* ; Inflammation/complications* ; Mice, Inbred C57BL ; Carrier Proteins/metabolism* ; Signal Transduction/drug effects* ; Lipopolysaccharides ; Thioredoxins/metabolism* ; Mice ; Lung/drug effects* ; Male ; Cell Line ; Interleukin-1beta/metabolism* ; Cell Cycle Proteins ; Stilbenes/therapeutic use*

OBJECTIVES: Osteoarthritis (OA) is one of the most common chronic degenerative diseases, with chondrocyte apoptosis and extracellular matrix (ECM) degradation as the major pathological changes. The mechanical stimulation can attenuate chondrocyte apoptosis and promote ECM synthesis, but the underlying molecular mechanisms remain unclear. This study aims to investigate the role of primary cilia (PC) in mediating the effects of mechanical stimulation on OA progression. METHODS: In vivo, conditional knockout mice lacking intraflagellar transport 88 (IFT88^flox/flox IFT88 knockout; i.e., primary cilia-deficient mice) were generated, with wild-type mice as controls. OA models were established via anterior cruciate ligament transection combined with destabilization of the medial meniscus, followed by treadmill exercise intervention. OA progression was evaluated by hematoxylin-eosin staining, safranin O-fast green staining, and immunohistochemistry; apoptosis was assessed by TUNEL staining; and limb function by rotarod testing. In vitro, primary articular chondrocytes were isolated from mice and transfected with lentiviral vectors to suppress IFT88 expression, thereby constructing a primary cilia-deficient cell model. Interleukin-1β (IL-1β) was used to induce an inflammatory environment, while cyclic tensile strain (CTS) was applied via a cell stretcher to mimic mechanical loading on chondrocytes. Immunofluorescence and Western blotting were used to detect the protein expression levels of type II collagen α1 chain (COL2A1), primary cilia, IFT88, and caspase-12; reverse transcription polymerase chain reaction was performed to assess COL2A1 mRNA levels; and flow cytometry was used to evaluate apoptosis. RESULTS: In vivo, treadmill exercise significantly reduced Osteoarthritis Research Society International (OARSI) scores and apoptotic cell rates, and improved balance ability in wild-type OA mice, whereas IFT88-deficient OA mice showed no significant improvement. In vitro, CTS inhibited IL-1β-induced ECM degradation and apoptosis in primary chondrocytes; however, this protective effect was abolished in cells with suppressed primary cilia expression. CONCLUSIONS Mechanical stimulation delays OA progression by mediating signal transduction through primary cilia, thereby inhibiting cartilage degeneration and chondrocyte apoptosis.
Animals ; Chondrocytes/cytology* ; Apoptosis/physiology* ; Mice ; Cilia/metabolism* ; Osteoarthritis/pathology* ; Extracellular Matrix/metabolism* ; Mice, Knockout ; Disease Progression ; Interleukin-1beta ; Male ; Cells, Cultured

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