OBJECTIVES: Sepsis-associated acute lung injury (S-ALI) is one of the major causes of death in intensive care unit (ICU) patients, yet its mechanisms remain incompletely understood and effective therapies are lacking. Lytic cell death of macrophages is a key driver of the inflammatory cascade in S-ALI. PANoptosis, a newly recognized form of lytic cell death characterized by PANoptosome assembly and activation, involves plasma membrane rupture (PMR) mediated by ninjurin-1 (NINJ1), a recently identified pore-forming protein. Itaconic acid is known for its anti-inflammatory effects, but its role in macrophage PANoptosis during S-ALI is unclear. This study aims to investigate the protective effect of itaconic acid on macrophage PANoptosis in S-ALI to provide new therapeutic insights. METHODS: Male specific-pathogen-free C57BL/6J mice (6-8 weeks, 18-20 g) received intraperitoneal lipopolysaccharide (LPS) to establish a classical S-ALI model. Western blotting was used to assess PANoptosome-related proteins and enzymes involved in the itaconic acid metabolic pathway, while real-time reverse transcription polymerase chain reaction and metabolomics quantified itaconic acid levels. Primary peritoneal macrophages (PMs) were pretreated with the itaconate derivative 4-octyl itaconate (4-OI) and then exposed to tumor necrosis factor alpha (TNF-α) plus interferon gamma (IFN-γ) to induce PANoptosis. Cell viability was evaluated by cell counting kit-8 (CCK-8) assay. Western blotting was employed to quantify enzymes of the itaconate-metabolic pathway in PANoptotic macrophages, to evaluate the impact of 4-OI on PANoptosome-associated proteins, and to determine NINJ1 abundance in lung tissues from S-ALI mice and in PANoptotic macrophages. Fluorescent dye FM_4-64 was used to visualize 4-OI-mediated changes in PMR, whereas immunofluorescence staining mapped the effect of 4-OI on both the expression level and membrane localization of NINJ1 in PANoptotic macrophages. The effect of 4-OI on lactate dehydrogenase (LDH) release in culture supernatants and peripheal blood serum was assessed using a LDH assay kit, and non-denataring polyacylamide gel electrophoresis was used to assess the expression of NINJ1 in S-ALI mouse lung tissues and the impact of 4-OI on the expression of PANoptosis-associated NINJ1 multimeric reflected protein in macropahges. RESULTS: In S-ALI mouse lungs, PANoptosome components [NOD-like receptor thermal protein domain associated protein 3 (NLRP3), Gasdermin D (GSDMD), Caspase-1, Z-DNA binding protein (ZBP1), and Caspase-3] and phosphorylated mixed lineage kinase domain-like protein (MLKL) S345 were significantly upregulated (all P<0.05), while metabolomics showed compensatory increases in itaconic acid and its key enzymes [aconitate decarboxylase 1 (ACOD1)/immunoresponsive gene 1 (IRG1)]. In macrophages, 4-OI obviously suppressed PANoptosome protein expression, reduced LDH release, restored plasma membrane integrity, and inhibited NINJ1 expression and oligomerization at the membrane (P<0.05). CONCLUSIONS Itaconic acid may alleviate macrophage PANoptosis in S-ALI by inhibiting NINJ1-mediated plasma membrane rupture. Targeting NINJ1 or enhancing itaconate pathways may offer a novel therapeutic strategy for S-ALI.
Animals ; Acute Lung Injury/pathology* ; Succinates/pharmacology* ; Sepsis/complications* ; Mice, Inbred C57BL ; Male ; Mice ; Macrophages/pathology* ; Cell Membrane/metabolism* ; Lipopolysaccharides ; Hydro-Lyases

OBJECTIVES: The integrated endoplasmic reticulum stress inhibitor (ISRIB) is a selective inhibitor of the protein kinase R-like endoplasmic reticulum kinase (PERK) signaling pathway within endoplasmic reticulum stress (ERS) and can improve spatial and working memory in aged mice. Although ERS and oxidative stress are tightly interconnected, it remains unclear whether ISRIB alleviates cognitive impairment by restoring the balance between ERS and oxidative stress. This study aims to investigate the effects and mechanisms of ISRIB on lipopolysaccharide (LPS)-induced cognitive impairment in mice. METHODS: Eight-week-old male ICR mice were randomly divided into 3 groups: Normal saline (NS) group, LPS group, and ISRIB+LPS group. NS and LPS groups received daily intraperitoneal injections of normal saline for 7 days; on day 7, LPS group mice received intraperitoneal LPS (0.83 mg/kg) to establish a cognitive impairment model. ISRIB+LPS group received ISRIB (0.25 mg/kg) intraperitoneally for 7 days, with LPS injected 30 minutes after ISRIB on day 7. Cognitive ability was evaluated by the novel place recognition test (NPRT). Real-time fluorogenic quantitative PCR (RT-qPCR) was used to detect changes in nitric oxide synthase (NOS), superoxide dismutase-1 (SOD-1), and catalase (CAT) gene expression in the hippocampus and prefrontal cortex. Oxidative stress markers malondialdehyde (MDA), glutathione (GSH), and oxidized glutathione (GSSG), were measured in hippocampal and prefrontal cortex tissues. RESULTS: Compared with the NS group, mice in LPS group showed a significant reduction in novel place recognition ratio, upregulation of hippocampal NOS-1 and NOS-2 mRNA, downregulation of SOD-1 and CAT mRNA, increased MDA and GSSG, decreased GSH, and reduced GSH/GSSG ratio (all P<0.05). Compared with the LPS group, mice in ISRIB+LPS group exhibited significantly improved novel place recognition, downregulated NOS-1 and NOS-2 mRNA, upregulated SOD-1 and CAT mRNA, decreased MDA and GSSG, increased GSH, and an elevated GSH/GSSG ratio in the hippocampus (all P<0.05). No significant changes were observed in the prefrontal cortex. CONCLUSIONS ISRIB improves LPS-induced cognitive impairment in mice by restoring the oxidative/antioxidant balance in the hippocampus.
Animals ; Lipopolysaccharides ; Male ; Mice, Inbred ICR ; Cognitive Dysfunction/drug therapy* ; Mice ; Oxidative Stress/drug effects* ; Endoplasmic Reticulum Stress/drug effects* ; Hippocampus/drug effects* ; Nitric Oxide Synthase Type II/genetics* ; Guanidines/pharmacology* ; eIF-2 Kinase/antagonists & inhibitors* ; Signal Transduction/drug effects* ; Superoxide Dismutase/metabolism*

Periodontitis is a common oral disease caused by bacteria coupled with an excessive host immune response. Stem cell therapy can be a promising treatment strategy for periodontitis, but the relevant mechanism is complicated. This study aimed to explore the therapeutic potential of mitochondria from human embryonic stem cell-derived mesenchymal stem cells (hESC-MSCs) for the treatment of periodontitis. The gingival tissues of periodontitis patients are characterized by abnormal mitochondrial structure. Human gingival fibroblasts (HGFs) were exposed to 5 μg/mL lipopolysaccharide (LPS) for 24 h to establish a cell injury model. When treated with hESC-MSCs or mitochondria derived from hESC-MSCs, HGFs showed reduced expression of inflammatory genes, increased adenosine triphosphate (ATP) level, decreased reactive oxygen species (ROS) production, and enhanced mitochondrial function compared to the control. The average efficiency of isolated mitochondrial transfer by hESC-MSCs was determined to be 8.93%. Besides, a therapy of local mitochondrial injection in mice with LPS-induced periodontitis showed a reduction in inflammatory gene expression, as well as an increase in both the mitochondrial number and the aspect ratio in gingival tissues. In conclusion, our results indicate that mitochondria derived from hESC-MSCs can reduce the inflammatory response and improve mitochondrial function in HGFs, suggesting that the transfer of mitochondria between hESC-MSCs and HGFs serves as a potential mechanism underlying the therapeutic effect of stem cells.
Humans ; Gingiva/cytology* ; Fibroblasts/metabolism* ; Mitochondria/physiology* ; Mesenchymal Stem Cells/cytology* ; Animals ; Periodontitis/therapy* ; Mice ; Reactive Oxygen Species/metabolism* ; Inflammation ; Lipopolysaccharides ; Human Embryonic Stem Cells/cytology* ; Cells, Cultured ; Adenosine Triphosphate/metabolism* ; Male

BACKGROUND: Periodontitis is characterized by alveolar bone resorption, aggravated by osteoblast dysfunction, and associated with intracellular oxidative stress linked to the nuclear factor erythroid 2-related factor 2 (NRF2) level. We evaluated the molecular mechanism of periodontitis onset and development and the role of NRF2 in osteogenic differentiation. METHODS: Primary murine mandibular osteoblasts were extracted and exposed to Porphyromonas gingivalis lipopolysaccharide (Pg-LPS) or other stimuli. Reactive oxygen species (ROS) and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1) staining were used to detect intracellular oxidative stress. Alkaline phosphatase staining and alizarin red S staining were used to detect the osteogenic differentiation of osteoblasts. Immunofluorescence and western blotting were used to determine the changes in the mitogen-activated protein kinase (MAPK) pathway and related molecule activities. Immunofluorescence colocalization and co-immunoprecipitation were performed to examine the nuclear translocation of NRF2 and its interaction with dual-specific phosphatase 1 (DUSP1) in cells. RESULTS: Ligated tissue samples showed higher alveolar bone resorption rate and lower NRF2 level than healthy periodontal tissue samples. Pg-LPS increased intracellular oxidative stress levels and inhibited osteogenic differentiation, whereas changes in NRF2 expression were correlated with changes in the oxidative stress and osteogenesis rate. NRF2 promoted the dephosphorylation of the MAPK pathway by nuclear translocation and the upregulation of DUSP1 expression, thus enhancing the osteogenic differentiation capacity of mandibular osteoblasts. The interaction between NRF2 and DUSP1 was observed. CONCLUSIONS: NRF2 and its nuclear translocation can regulate the osteogenic differentiation of mandibular osteoblasts under Pg-LPS conditions by interacting with DUSP1 in a process linked to the MAPK pathway. These findings form the basis of periodontitis treatment.
Animals ; NF-E2-Related Factor 2/physiology* ; Lipopolysaccharides/pharmacology* ; Osteoblasts/drug effects* ; Mice ; Porphyromonas gingivalis/chemistry* ; Cell Differentiation ; Osteogenesis ; Dual Specificity Phosphatase 1/metabolism* ; Mandible/cytology* ; Reactive Oxygen Species/metabolism* ; Oxidative Stress ; Periodontitis/metabolism* ; Cells, Cultured ; Male ; Cell Nucleus/metabolism*

Preeclampsia (PE) is a severe gestational disorder characterized by hypertension and proteinuria, with a subset of cases exhibiting an immune-driven phenotype marked by placental overexpression of proinflammatory cytokines and chronic inflammatory damage, profoundly impacting fetal development. To elucidate the pathophysiology of this PE subtype, we established an inflammation-driven PE mouse model via lipopolysaccharide (LPS) intraperitoneal injection, systematically evaluating histopathological changes in maternal heart, liver, lung, kidney, and placenta, and integrating transcriptomic profiling to uncover molecular mechanisms. LPS administration robustly induced maternal hypertension and proteinuria, hallmarks of PE, without significantly altering organ or fetal weights. Histological analyses revealed pronounced inflammatory damage in the maternal lung, kidney, and placenta, with the lung exhibiting the most severe pathology, characterized by inflammatory cell infiltration, alveolar wall thickening, and interstitial edema-challenging the conventional focus on placental and renal primacy in PE. Placental labyrinth and junctional zones displayed extensive structural disruption and necrosis, indicating functional impairment. Transcriptomic analysis identified 27 inflammation-related genes consistently upregulated across tissues, with protein-protein interaction networks pinpointing Il1β, Il6, Ccl5, Ccl2, Cxcl10, Tlr2, and Icam1 as hub genes. Quantitative PCR validation confirmed Tlr2 as a central regulator, evidenced by significant upregulation of Tlr2 in lung, kidney, and placenta of LPS-induced PE mice, while Cxcl10 exhibited placenta-specific upregulation, suggesting a synergistic inflammatory axis in placental pathology. These findings highlight the lung as a critical, yet underappreciated, target in inflammation-driven PE, reframe the multi-organ inflammatory landscape of the disease, and nominate Tlr2 and Cxcl10 as potential diagnostic biomarkers and therapeutic targets, offering new avenues for precision intervention in PE.
Animals ; Female ; Pregnancy ; Mice ; Pre-Eclampsia/genetics* ; Inflammation ; Lipopolysaccharides/adverse effects* ; Disease Models, Animal ; Transcriptome ; Placenta/pathology* ; Phenotype

This paper investigated the inhibitory effect of carbonized Scutellariae Radix(Cb-SR) on pyroptosis in endometrial epithelial cells of mice with endometritis and its correlation with the IKBKE/NLRP3 signaling axis. Mice model of endometritis was established by using an intrauterine injection of 10 μL polysaccharides(LPS, 5 mg·mL~(-1)), and the mice were randomly divided into model group(LPS), low-dose group of Cb-SR(L-Cb-SR, 0.55 g·kg~(-1)), medium-dose group of Cb-SR(M-Cb-SR, 1.10 g·kg~(-1)), high-dose group of Cb-SR(H-Cb-SR, 2.20 g·kg~(-1)), crude Scutellariae Radix group(Cr-SR, 1.63 g·kg~(-1)), and Fuke Qianjin Capsule group(FQC, 0.30 g·kg~(-1)), with 10 mice in each group. Ten healthy female mice were selected and injected with PBS of equal volume into the bilateral uterus, and they were set as the sham group. The mice in the drug treatment groups were given the corresponding doses of Cb-SR, Cr-SR, FQC, or physiological saline of equal volume by gavage twice a day for seven days. Thirty minutes after the last administration, each mouse was euthanized by cervical dislocation. Hematoxylin-eosin(HE) staining and transmission electron microscopy were applied to observe the histopathological morphology of the uterine tissue. Immunohistochemistry was used to detect the expression of CD38 and CD138. Myeloperoxidase(MPO) values in neutrophils were measured by the kit; Enzyme-linked immunosorbent assay(ELISA) was used to measure the secretion of interleukin-18(IL-18), interleukin-1β(IL-1β), and tumor necrosis factor-α(TNF-α). Immunofluorescence and Western blot were used to analyze the expression of the proteins related to the IKBKE/NLRP3 signaling axis. Mouse endometrial epithelial cells(MEECs) were separated and purified from the uterine tissue of pregnant female mice through in vitro experiments and injured by LPS for 24 h, and then they were cultured with Cb-SR-containing serum. The anti-endometritis effect of Cb-SR was investigated by CCK-8 assay, scanning electron microscopy, and Western blot. The results showed that Cb-SR significantly reduced MPO values, attenuated uterine tissue damage, inhibited the expression of CD38 and CD138, decreased the levels of IL-1β, IL-18, and TNF-α, and inhibited the expression of proteins associated with IKBKE/NLRP3 signaling axis in mice with endometritis. In addition, Cb-SR-containing serum reduced swelling of MEECs organelles induced by LPS, decreased the expression of inflammatory factors, and suppressed the expression of IKBKE/NLRP3 signaling axis-related proteins. These results suggest that Cb-SR can inhibit endometrial epithelial cell pyroptosis in endometritis by suppressing the IKBKE/NLRP3 signaling axis.
Animals ; Female ; Mice ; Pyroptosis/drug effects* ; Signal Transduction/drug effects* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Drugs, Chinese Herbal/chemistry* ; Endometritis/chemically induced* ; Lipopolysaccharides/adverse effects* ; Scutellaria baicalensis/chemistry* ; Humans ; Epithelial Cells/drug effects*

In this study, lipopolysaccharide(LPS), ovalbumin(OVA), and compound 48/80(C48/80) were administered to establish non-infectious pneumonia models under simulated clinical conditions, and the correlation between their pathological characteristics and traditional Chinese medicine(TCM) syndromes was compared, providing the basis for the selection of appropriate animal models for TCM efficacy evaluation. An acute pneumonia model was established by nasal instillation of LPS combined with intraperitoneal injection for intensive stimulation. Three doses of OVA mixed with aluminum hydroxide adjuvant were injected intraperitoneally on days one, three, and five and OVA was administered via endotracheal drip for excitation on days 14-18 to establish an OVA-induced allergic pneumonia model. A single intravenous injection of three doses of C48/80 was adopted to establish a C48/80-induced pneumonia model. By detecting the changes in peripheral blood leukocyte classification, lung tissue and plasma cytokines, immunoglobulins(Ig), histamine levels, and arachidonic acid metabolites, the multi-dimensional analysis was carried out based on pathological evaluation. The results showed that the three models could cause pulmonary edema, increased wet weight in the lung, and obvious exudative inflammation in lung tissue pathology, especially for LPS. A number of pyrogenic cytokines, inclading interleukin(IL)-6, interferon(IFN)-γ, IL-1β, and IL-4 were significantly elevated in the LPS pneumonia model. Significantly increased levels of prostacyclin analogs such as prostaglandin E2(PGE2) and PGD2, which cause increased vascular permeability, and neutrophils in peripheral blood were significantly elevated. The model could partly reflect the clinical characteristics of phlegm heat accumulating in the lung or dampness toxin obstructing the lung. The OVA model showed that the sensitization mediators IgE and leukotriene E4(LTE4) were increased, and the anti-inflammatory prostacyclin 6-keto-PGF2α was decreased. Immune cells(lymphocytes and monocytes) were decreased, and inflammatory cells(neutrophils and basophils) were increased, reflecting the characteristics of "deficiency", "phlegm", or "dampness". Lymphocytes, monocytes, and basophils were significantly increased in the C48/80 model. The phenotype of the model was that the content of histamine, a large number of prostacyclins(6-keto-PGE1, PGF2α, 15-keto-PGF2α, 6-keto-PGF1α, 13,14-D-15-keto-PGE2, PGD2, PGE2, and PGH2), LTE4, and 5-hydroxyeicosatetraenoic acid(5S-HETE) was significantly increased, and these indicators were associated with vascular expansion and increased vascular permeability. The pyrogenic inflammatory cytokines were not increased. The C48/80 model reflected the characteristics of cold and damp accumulation. In the study, three non-infectious pneumonia models were constructed. The LPS model exhibited neutrophil infiltration and elevated inflammatory factors, which was suitable for the efficacy study of TCM for clearing heat, detoxifying, removing dampness, and eliminating phlegm. The OVA model, which took allergic inflammation as an index, was suitable for the efficacy study of Yiqi Gubiao formulas. The C48/80 model exhibited increased vasoactive substances(histamine, PGs, and LTE4), which was suitable for the efficacy study and evaluation of TCM for warming the lung, dispersing cold, drying dampness, and resolving phlegm. The study provides a theoretical basis for model selection for the efficacy evaluation of TCM in the treatment of pneumonia.
Animals ; Disease Models, Animal ; Mice ; Pneumonia/genetics* ; Medicine, Chinese Traditional ; Male ; Humans ; Cytokines/immunology* ; Female ; Lipopolysaccharides/adverse effects* ; Lung/drug effects* ; Drugs, Chinese Herbal ; Ovalbumin ; Mice, Inbred BALB C

Objective To investigate the gene expression and regulatory mechanisms of mouse embryonic fibroblasts (MEFs) under inflammatory conditions, aiming to elucidate the role of MEFs in inflammatory responses and provide a foundation for discovering anti-inflammatory drugs that act by modulating MEF function. Methods MEFs cultured in vitro were divided into the following groups: lipopolysaccharides (LPS)-treated group, inflammatory conditioned medium (CM)-treated group, and control group, which were treated with LPS, CM, and equal volume solvent, respectively. Transcriptome sequencing was used to analyze the effects of two stimuli on gene expression profile of MEFs. Real time fluorescence quantitative PCR (RT-qPCR) was employed to verify the transcription levels of highly expressed genes of MEFs induced by CM. ELISA was performed to determine the concentrations of cytokines in cell supernatants. Finally, the regulatory effects of CM on the activation of signaling pathways in MEFs were analyzed by immunoblotting. Results Transcriptome analysis showed that both LPS and CM induced the transcription of a large number of genes in MEFs. Compared with LPS, CM potentiated the mRNA transcription of some acute phase proteins, inflammatory cytokines, chemokines, matrix metalloproteinases (MMP), prostaglandin synthetases, and colony-stimulating factors. The transcriptome analysis was verified by RT-qPCR. The results of ELISA showed that CM treatment significantly increased the secretion of interleukin 6 (IL-6), C-C motif chemokine ligand (CCL2), and C-X-C motif chemokine ligand (CXCL1) by MEFs compared with LPS. Mechanism study showed that both LPS and CM induced the phosphorylation of nuclear factor-κB p65 (NF-κB p65), p38 mitogen-activated protein kinase (p38 MAPK), extracellular regulated protein kinases 1/2 (ERK1/2), and TANK-binding kinase (TBK) in MEFs, and CM strongly stimulated the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in MEFs. Conclusion Both LPS and CM can induce transcription and protein secretion of various inflammation-related genes in MEFs. CM can partly enhance LPS-induced activation of MEFs, and the mechanism may be related to the enhancement effect of CM on the activation STAT3 signaling pathway.
Animals ; Fibroblasts/immunology* ; Mice ; Lipopolysaccharides/pharmacology* ; Inflammation/metabolism* ; Signal Transduction/drug effects* ; Gene Expression Regulation/drug effects* ; Cytokines/genetics* ; Culture Media, Conditioned/pharmacology* ; Cells, Cultured

OBJECTIVE: To explore the effect of bear bile powder (BBP) on acute lung injury (ALI) and the underlying mechanism. METHODS: The chemical constituents of BBP were analyzed by ultra-high-pressure liquid chromatography-mass spectrometry (UPLC-MS). After 7 days of adaptive feeding, 50 mice were randomly divided into 5 groups by a random number table (n=10): normal control (NC), lipopolysaccharide (LPS), dexamethasone (Dex), low-, and high-dose BBP groups. The dosing cycle was 9 days. On the 12th and 14th days, 20 µL of Staphylococcus aureus solution (bacterial concentration of 1 × 10^-7 CFU/mL) was given by nasal drip after 1 h of intragastric administration, and the mice in the NC group was given the same dose of phosphated buffered saline (PBS) solution. On the 16th day, after 1 h intragastric administration, 100 µL of LPS solution (1 mg/mL) was given by tracheal intubation, and the same dose of PBS solution was given to the NC group. Lung tissue was obtained to measure the myeloperoxidase (MPO) activity, the lung wet/dry weight ratio and expressions of CD14 and other related proteins. The lower lobe of the right lung was obtained for pathological examination. The concentrations of inflammatory cytokines including interleukin (IL)-6, tumour necrosis factor α (TNF-α ) and IL-1β in the bronchoalveolar lavage fluid (BALF) were detected by enzyme linked immunosorbent assay, and the number of neutrophils was counted. The colonic contents of the mice were analyzed by 16 sRNA technique and the contents of short-chain fatty acids (SCFAs) were measured by gas chromatograph-mass spectrometer (GC-MS). RESULTS: UPLC-MS revealed that the chemical components of BBP samples were mainly tauroursodeoxycholic acid and taurochenodeoxycholic acid sodium salt. BBP reduced the activity of MPO, concentrations of inflammatory cytokines, and inhibited the expression of CD14 protein, thus suppressing the activation of NF-κB pathway (P<0.05). The lung histopathological results indicated that BBP significantly reduced the degree of neutrophil infiltration, cell shedding, necrosis, and alveolar cavity depression. Moreover, BBP effectively regulated the composition of the intestinal microflora and increased the production of SCFAs, which contributed to its treatment effect (P<0.05). CONCLUSIONS BBP alleviates lung injury in ALI mouse through inhibiting activation of NF-κB pathway and decreasing expression of CD14 protein. BBP may promote recovery of ALI by improving the structure of intestinal flora and enhancing metabolic function of intestinal flora.
Animals ; Acute Lung Injury/pathology* ; Lipopolysaccharides ; Ursidae ; Gastrointestinal Microbiome/drug effects* ; Bile/chemistry* ; Lipopolysaccharide Receptors/metabolism* ; Powders ; Male ; Lung/drug effects* ; Mice ; Peroxidase/metabolism* ; Signal Transduction/drug effects* ; Cytokines/metabolism*

OBJECTIVE: To investigate the anti-inflammatory effect of rutaecarpine (RUT) on monosodium urate crystal (MSU)-induced murine peritonitis in mice and further explored the underlying mechanism of RUT in lipopolysaccharide (LPS)/MSU-induced gout model in vitro. METHODS: In MSU-induced mice, 36 male C57BL/6 mice were randomly divided into 6 groups of 8 mice each group, including the control group, model group, RUT low-, medium-, and high-doses groups, and prednisone acetate group. The mice in each group were orally administered the corresponding drugs or vehicle once a day for 7 consecutive days. The gout inflammation model was established by intraperitoneal injection of MSU to evaluate the anti-gout inflammatory effects of RUT. Then the proinflammatory cytokines were measured by enzyme-linked immunosorbent assay (ELISA) and the proportions of infiltrating neutrophils cytokines were detected by flow cytometry. In LPS/MSU-treated or untreated THP-1 macrophages, cell viability was observed by cell counting kit 8 and proinflammatory cytokines were measured by ELISA. The percentage of pyroptotic cells were detected by flow cytometry. Respectively, the mRNA and protein levels were measured by real-time quantitative polymerase chain reaction (qRT-PCR) and Western blot, the nuclear translocation of nuclear factor κB (NF-κB) p65 was observed by laser confocal imaging. Additionally, surface plasmon resonance (SPR) and molecular docking were applied to validate the binding ability of RUT components to tumor necrosis factor α (TNF-α) targets. RESULTS: RUT reduced the levels of infiltrating neutrophils and monocytes and decreased the levels of the proinflammatory cytokines interleukin 1β (IL-1β) and interleukin 6 (IL-6, all P<0.01). In vitro, RUT reduced the production of IL-1β, IL-6 and TNF-α. In addition, RT-PCR revealed the inhibitory effects of RUT on the mRNA levels of IL-1β, IL-6, cyclooxygenase-2 and TNF-α (P<0.05 or P<0.01). Mechanistically, RUT markedly reduced protein expressions of tumor necrosis factor receptor (TNFR), phospho-mitogen-activated protein kinase (p-MAPK), phospho-extracellular signal-regulated kinase, phospho-c-Jun N-terminal kinase, phospho-NF-κB, phospho-kinase α/β, NOD-like receptor thermal protein domain associated protein 3 (NLRPS), cleaved-cysteinyl aspartate specific proteinase-1 and cleaved-gasdermin D in macrophages (P<0.05 or P<0.01). Molecularly, SPR revealed that RUT bound to TNF-α with a calculated equilibrium dissociation constant of 31.7 µmol/L. Molecular docking further confirmed that RUT could interact directly with the TNF-α protein via hydrogen bonding, van der Waals interactions, and carbon-hydrogen bonding. CONCLUSION RUT alleviated MSU-induced peritonitis and inhibited the TNFR1-MAPK/NF-κB and NLRP3 inflammasome signaling pathway to attenuate gouty inflammation induced by LPS/MSU in THP-1 macrophages, suggesting that RUT could be a potential therapeutic candidate for gout.
Animals ; NF-kappa B/metabolism* ; Male ; Indole Alkaloids/therapeutic use* ; Signal Transduction/drug effects* ; Mice, Inbred C57BL ; Inflammation/complications* ; Uric Acid ; Quinazolines/therapeutic use* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Humans ; Gout/chemically induced* ; Inflammasomes/metabolism* ; Cytokines/metabolism* ; THP-1 Cells ; Mitogen-Activated Protein Kinases/metabolism* ; Mice ; Molecular Docking Simulation ; Lipopolysaccharides ; Quinazolinones