This study aims to explore the intervention effects of isorhamnetin(Isor) on acute lung injury(ALI) and its regulatory effects on pyroptosis mediated by the NOD-like receptor family pyrin domain containing 3(NLRP3)/apoptosis-associated speck-like protein containing a CARD(ASC)/cysteine aspartate-specific protease-1(caspase-1) axis. In the in vivo experiments, 60 BALB/c mice were divided into five groups. Except for the control group, the other groups were administered Isor by gavage 1 hour before intratracheal instillation of LPS to induce ALI, and tissues were collected after 12 hours. In the in vitro experiments, RAW264.7 cells were divided into five groups. Except for the control group, the other groups were pretreated with Isor for 2 hours before LPS stimulation and subsequent assessments. Hematoxylin-eosin(HE) staining was used to observe pathological changes in lung tissue, while lung swelling, protein levels in bronchoalveolar lavage fluid(BALF), and myeloperoxidase(MPO) levels in lung tissue were measured. Cell proliferation toxicity and viability were assessed using the cell counting kit-8(CCK-8) method. Enzyme-linked immunosorbent assay(ELISA) was used to detect the levels of interleukin-1β(IL-1β), IL-6, IL-18, and tumor necrosis factor-α(TNF-α). Protein levels of NLRP3, ASC, cleaved caspase-1, and the N-terminal fragment of gasdermin D(GSDMD-N) were evaluated using immunohistochemistry, immunofluorescence, and Western blot. The results showed that in the in vivo experiments, Isor significantly improved pathological damage in lung tissue, reduced lung swelling, protein levels in BALF, MPO levels in lung tissue, and levels of inflammatory cytokines such as IL-1β, IL-6, IL-18, and TNF-α, and inhibited the high expression of the NLRP3/ASC/caspase-1 axis and the pyroptosis core gene GSDMD-N. In the in vitro experiments, the safe dose of Isor was determined through cell proliferation toxicity assays. Isor reduced cell death and inhibited the expression levels of the NLRP3/ASC/caspase-1 axis, GSDMD-N, and inflammatory cytokines. In conclusion, Isor may alleviate ALI by modulating pyroptosis mediated by the NLRP3/ASC/caspase-1 axis.
Animals ; Pyroptosis/drug effects* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics* ; Acute Lung Injury/physiopathology* ; Mice ; Mice, Inbred BALB C ; Quercetin/pharmacology* ; Caspase 1/genetics* ; CARD Signaling Adaptor Proteins/genetics* ; Male ; RAW 264.7 Cells ; Humans ; Lung/metabolism*

Sepsis is a systemic inflammatory response caused by severe infection or trauma, and is one of the common causes of acute lung injury(ALI) and acute respiratory distress syndrome(ARDS). Sepsis-acute lung injury(SALI) is a critical clinical condition with high morbidity and mortality. Its pathogenesis is complex and not yet fully understood, and there is currently a lack of targeted and effective treatment options. Pyroptosis, a novel form of programmed cell death, plays a key role in the pathological process of SALI by activating inflammasomes and releasing inflammatory factors, making it a potential therapeutic target. In recent years, the role of traditional Chinese medicine(TCM) in regulating signaling pathways related to pyroptosis through multi-components and multi-targets has attracted increasing attention. TCM may intervene in pyroptosis by inhibiting the activation of NLRP3 inflammasomes and regulating the expression of Caspase family proteins, thus alleviating inflammatory damage in lung tissues. This paper systematically reviews the molecular regulatory network of pyroptosis in SALI and explores the potential mechanisms and research progress on TCM intervention in cellular pyroptosis. The aim is to provide new ideas and theoretical support for basic research and clinical treatment strategies of TCM in SALI.
Pyroptosis/drug effects* ; Humans ; Sepsis/genetics* ; Acute Lung Injury/physiopathology* ; Animals ; Drugs, Chinese Herbal/therapeutic use* ; Medicine, Chinese Traditional ; Inflammasomes/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/genetics*

OBJECTIVES: Acute lung injury (ALI) is an acute respiratory failure syndrome characterized by impaired gas exchange. Due to the lack of effective targeted drugs, it is associated with high mortality and poor prognosis. Tripterygium wilfordii (TW) has demonstrated anti-inflammatory activity in the treatment of various diseases. This study aims to investigate the effects and underlying mechanisms of TW on myeloid-derived suppressor cells (MDSCs) in ALI, providing experimental evidence for TW as a potential adjuvant therapy for ALI. METHODS: Eighteen specific pathogen-free (SPF) C57BL/6 mice were randomly divided into normal control (NC; intranasal saline), lipopolysaccharide (LPS; 5 mg/kg intranasally to induce ALI), and LPS+TW (50 mg/kg TW by gavage on the first day of modeling, followed by 5 mg/kg LPS intranasally to induce ALI) groups (n=6 each). Lung injury and edema were assessed by histopathological scoring and wet-to-dry weight ratio. Cytokine levels [interleukin (IL)-1β, IL-6, IL-18, tumor necrosis factor-α (TNF-α)] in lung tissue lavage fluid were measured by enzyme-linked immunosorbent assay (ELISA). Flow cytometry was used to assess the proportions of MDSCs, polymorphonuclear MDSCs (PMN-MDSCs), and monocytic MDSCs (M-MDSCs) in bone marrow, spleen, peripheral blood, and lung tissue, as well as reactive oxygen species (ROS) levels in lung tissues. Messenger RNA (mRNA) expression levels of inducible nitric oxide synthase (iNOS) and arginase-1 (ARG-1) in lung tissues were determined by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR). PMN-MDSCs sorted from the lungs of LPS-treated mice were co-cultured with splenic CD3⁺ T cells and divided into NC, triptolide (TPL)-L, and TPL-H groups, with bovine serum albumin, 25 nmol/L TPL, and 50 nmol/L TPL, respectively. Flow cytometry was used to detect the effect of PMN-MDSCs on T-cell proliferation, and RT-qPCR was used to measure iNOS and ARG-1 mRNA expression. RESULTS: Compared with the NC group, the LPS group showed marked lung pathology with significantly increased histopathological scores and wet-to-dry ratios (both P<0.001). TW treatment significantly alleviated lung injury and reduced both indices compared with the LPS group (both P<0.05). Cytokine levels were significantly decreased in the LPS+TW group compared with the LPS group (all P<0.001). The proportions of MDSCs in CD45⁺ cells from spleen, bone marrow, peripheral blood, and lung, as well as PMN-MDSCs from spleen, peripheral blood, and lung, were significantly reduced in the LPS+TW group compared with the LPS group (all P<0.05), accompanied by reduced ROS levels in lung tissues (P<0.001). iNOS and ARG-1 mRNA expression in lung tissues was significantly lower in the LPS+TW group than in the LPS group (both P<0.001). In vitro, compared with the TPL-L group, the TPL-H group showed significantly increased CD3⁺ T-cell proliferation (P<0.001), and decreased iNOS and ARG-1 mRNA expression (all P<0.05). CONCLUSIONS TW alleviates the progression of LPS-induced ALI in mice, potentially by reducing the proportion of MDSCs in lung tissues and attenuating the immunosuppressive function of PMN-MDSCs.
Animals ; Acute Lung Injury/chemically induced* ; Myeloid-Derived Suppressor Cells/cytology* ; Tripterygium/chemistry* ; Mice, Inbred C57BL ; Mice ; Cell Differentiation/drug effects* ; Male ; Lipopolysaccharides ; Nitric Oxide Synthase Type II/genetics* ; Cytokines/metabolism* ; Reactive Oxygen Species/metabolism* ; Diterpenes/pharmacology* ; Epoxy Compounds ; Phenanthrenes

Acute lung injury (ALI) is a severe disease caused by viral infection that triggers an uncontrolled inflammatory response. This study investigated the capacity of jasurolignoside (JO), a natural compound, to bind to Toll-like receptor 4 (TLR4) and treat ALI. The anti-inflammatory properties of JO were evaluated in vitro through Western blotting, enzyme-linked immunosorbent assay (ELISA), immunofluorescence staining, and co-immunoprecipitation. The investigation utilized a lipopolysaccharide (LPS)-induced ALI animal model to examine the therapeutic efficacy and mechanism of JO in vivo. JO attenuated inflammatory symptoms in infected cells and tissues by modulating the NOD-like receptor family pyrin domain containing protein 3 (NLRP3) inflammasome and the nuclear factor κB (NF-κB)/mitogen-activated protein kinase (MAPK) pathway. Molecular docking simulations revealed JO binding to TLR4 active sites, confirmed by cellular thermal shift assay. Surface plasmon resonance (SPR) demonstrated direct interaction between JO and TLR4 with a Kd value of 35.1 μmol·L^-1. Moreover, JO inhibited tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6 secretion and reduced leukocyte, neutrophil, lymphocyte, and macrophage infiltration in ALI-affected mice. JO also enhanced lung function and reduced ALI-related mortality. Immunohistochemical staining demonstrated JO's ability to suppress TLR4 expression in ALI-affected mouse lung tissue. This study establishes that JO can bind to TLR4 and effectively treat ALI, indicating its potential as a therapeutic agent for clinical applications.
Toll-Like Receptor 4/chemistry* ; Animals ; Acute Lung Injury/chemically induced* ; Mice ; Humans ; Ilex/chemistry* ; Molecular Docking Simulation ; Male ; NF-kappa B/immunology* ; Mice, Inbred C57BL ; NLR Family, Pyrin Domain-Containing 3 Protein/immunology* ; Tumor Necrosis Factor-alpha/genetics* ; Interleukin-1beta/genetics* ; RAW 264.7 Cells ; Disease Models, Animal

Acute lung injury (ALI) is a significant complication of sepsis, characterized by high morbidity, mortality, and poor prognosis. Neutrophils, as critical intrinsic immune cells in the lung, play a fundamental role in the development and progression of ALI. During ALI, neutrophils generate neutrophil extracellular traps (NETs), and excessive NETs can intensify inflammatory injury. Research indicates that Taohe Chengqi decoction (THCQD) can ameliorate sepsis-induced lung inflammation and modulate immune function. This study aimed to investigate the mechanisms by which THCQD improves ALI and its relationship with NETs in sepsis patients, seeking to provide novel perspectives and interventions for clinical treatment. The findings demonstrate that THCQD enhanced survival rates and reduced lung injury in the cecum ligation and puncture (CLP)-induced ALI mouse model. Furthermore, THCQD diminished neutrophil and macrophage infiltration, inflammatory responses, and the production of pro-inflammatory cytokines, including interleukin-1β (IL-1β), IL-6, and tumor necrosis factor α (TNF-α). Notably, subsequent experiments confirmed that THCQD inhibits NET formation both in vivo and in vitro. Moreover, THCQD significantly decreased the expression of peptidyl arginine deiminase 4 (PAD4) protein, and molecular docking predicted that certain active compounds in THCQD could bind tightly to PAD4. PAD4 overexpression partially reversed THCQD's inhibitory effects on PAD4. These findings strongly indicate that THCQD mitigates CLP-induced ALI by inhibiting PAD4-mediated NETs.
Extracellular Traps/immunology* ; Acute Lung Injury/immunology* ; Animals ; Sepsis/immunology* ; Drugs, Chinese Herbal/pharmacology* ; Mice ; Neutrophils/immunology* ; Male ; Protein-Arginine Deiminase Type 4/genetics* ; Mice, Inbred C57BL ; Humans ; Disease Models, Animal ; Cytokines/metabolism*

The study is designed to observe the mechanism of Tongfu Xiefei Guanchang Solution(TFXF) in the treatment of acute lung injury(ALI) in rats by improving intestinal barrier and intestinal flora structure via p38 mitogen-activated protein kinase(p38 MAPK)/myosin light chain kinase(MLCK) signaling pathway. Sixty SPF-grade Wistar rats were randomly divided into the control(CON) group, lipopolysaccharide(LPS) group(7.5 mg·kg~(-1)), LPS + dexamethasone(DEX) group(3.5 mg·kg~(-1)), LPS + high-dose(HD)-TFXF group(14.74 g·kg~(-1)), LPS + middle-dose(MD)-TFXF group(7.37 g·kg~(-1)), and LPS + low-dose(LD)-TFXF group(3.69 g·kg~(-1)). ALI model of the rat was established by intraperitoneal injection of LPS. The lactate dehydrogenase(LDH) activity and total protein concentration in the bronchoalveolar lavage fluid(BALF) were measured; tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) levels in lung and colon tissue of rats were detected by enzyme linked immunosorbent assay(ELISA). Hematoxylin-eosin(HE) staining was used to observe the pathological expression in the lung and colon tissue of rats. The mRNA expression of p38 MAPK, TNF-α, and IL-1β in rat lung tissue was determined by real-time fluorescence quantitative polymerase chain reaction(real-time PCR). Western blot was used to detect the protein expression related to the p38 MAPK/MLCK signaling pathway in the colon tissue of rats. 16S rRNA sequencing was used to detect changes in the composition and content of intestinal flora in rats, and correlation analyses were performed to explore the regulatory role of intestinal flora in improving ALI in rats. The results showed that compared with those in the LPS group, the histopathological scores of lung and colon tissue, LDH activity, and total protein concentration in BALF were significantly reduced in rats in all groups after drug administration. Except for the LPS + LD-TFXF group, the remaining groups significantly reduced the levels of TNF-α and IL-1β in the lung and colon tissue of rats. The protein expressions of phosphorylated p38 mitogen-activated protein kinase(p-p38 MAPK)/p38, phosphorylated myosin light chain(p-MLC)/myosin light chain 2(MLC2), and MLCK in colon tissue of rats in each drug administration group were significantly decreased. The mRNA expression levels of p38 MAPK, TNF-α, and IL-1β were significantly reduced in the LPS + HD-TFXF group. 16S rRNA sequencing results showed that the abundance of intestinal flora was significantly higher in the LPS + HD-TFXF group, and intestinal floras including Sobs, Shannon, and Npshannon were significantly higher. The β-diversity distribution of intestinal flora tends toward the CON group, and the abundance of Firmicutes was significantly higher. The abundance of Proteobacteria was significantly reduced; the abundance of Bacteroides was significantly reduced, and the abundance of Ruminococcus was significantly higher. The main species differences were Blautia, Roseburia＿sp＿499, and Butyricicoccus. TNF-α and IL-1β of lung tissue were negatively correlated with Muribaculaceae, unclassified norank＿f＿Eubacterium＿coprostanoligenes, and Ruminococcus and positively correlated with Bacteroides. Meanwhile, TNF-α and IL-1β of colon tissue were negatively correlated with unclassified norank＿f＿Eubacterium＿coprostanoligenes and Ruminococcus and positively correlated with Bacteroides. The predicted biological function of the flora was related to the biosynthesis of secondary metabolites, amino acid biosynthesis, sugar metabolism, and oxidative phosphorylation. The above studies show that TFXF can repair lung and colon tissue structure and regulate inflammatory factor levels by modulating the abundance and diversity of intestinal flora species in ALI rats. Its mechanism of action in ameliorating ALI in rats may be related to the inhibition of inflammation, improvement of intestinal mucosal permeability, and maintenance of intestinal flora homeostasis and barrier through the p38 MAPK/MLCK signaling pathway.
Animals ; Acute Lung Injury/genetics* ; Rats ; p38 Mitogen-Activated Protein Kinases/genetics* ; Drugs, Chinese Herbal/pharmacology* ; Myosin-Light-Chain Kinase/genetics* ; Male ; Gastrointestinal Microbiome/drug effects* ; Rats, Wistar ; Signal Transduction/drug effects* ; Interleukin-1beta/metabolism* ; Tumor Necrosis Factor-alpha/metabolism* ; Lung/metabolism* ; Intestinal Mucosa/metabolism* ; Humans

This study aimed to investigate the biological effects and underlying mechanisms of the total ginsenosides from Panax ginseng stems and leaves on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice. Sixty male C57BL/6J mice were randomly divided into a control group, a model group, the total ginsenosides from P. ginseng stems and leaves normal administration group(61.65 mg·kg~(-1)), and low-, medium-, and high-dose total ginsenosides from P. ginseng stems and leaves groups(15.412 5, 30.825, and 61.65 mg·kg~(-1)). Mice were administered for seven continuous days before modeling. Twenty-four hours after modeling, mice were sacrificed to obtain lung tissues and calculate lung wet/dry ratio. The number of inflammatory cells in bronchoalveolar lavage fluid(BALF) was detected. The levels of interleukin-1β(IL-1β), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in BALF were detected. The mRNA expression levels of IL-1β, IL-6, and TNF-α, and the levels of myeloperoxidase(MPO), glutathione peroxidase(GSH-Px), superoxide dismutase(SOD), and malondialdehyde(MDA) in lung tissues were determined. Hematoxylin-eosin(HE) staining was used to observe the pathological changes in lung tissues. The gut microbiota was detected by 16S rRNA sequencing, and gas chromatography-mass spectrometry(GC-MS) was applied to detect the content of short-chain fatty acids(SCFAs) in se-rum. The results showed that the total ginsenosides from P. ginseng stems and leaves could reduce lung index, lung wet/dry ratio, and lung damage in LPS-induced ALI mice, decrease the number of inflammatory cells and levels of inflammatory factors in BALF, inhibit the mRNA expression levels of inflammatory factors and levels of MPO and MDA in lung tissues, and potentiate the activity of GSH-Px and SOD in lung tissues. Furthermore, they could also reverse the gut microbiota disorder, restore the diversity of gut microbiota, increase the relative abundance of Lachnospiraceae and Muribaculaceae, decrease the relative abundance of Prevotellaceae, and enhance the content of SCFAs(acetic acid, propionic acid, and butyric acid) in serum. This study suggested that the total ginsenosides from P. ginseng stems and leaves could improve lung edema, inflammatory response, and oxidative stress in ALI mice by regulating gut microbiota and SCFAs metabolism.
Mice ; Male ; Animals ; Ginsenosides/pharmacology* ; Tumor Necrosis Factor-alpha/metabolism* ; Interleukin-6 ; Panax/genetics* ; Lipopolysaccharides/adverse effects* ; Gastrointestinal Microbiome ; RNA, Ribosomal, 16S ; Mice, Inbred C57BL ; Acute Lung Injury/genetics* ; Lung/metabolism* ; Superoxide Dismutase/metabolism* ; Plant Leaves/metabolism* ; RNA, Messenger

This study aimed to explore the mechanism of Qilongtian Capsules in treating acute lung injury(ALI) based on network pharmacology prediction and in vitro experimental validation. Firstly, UPLC-Q-TOF-MS/MS was used to analyze the main chemical components of Qilongtian Capsules, and related databases were used to obtain its action targets and ALI disease targets. STRING database was used to build a protein-protein interaction(PPI) network. Metascape database was used to conduct enrichment analysis of Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG). AutoDock software was used to perform molecular docking verification on the main active components and key targets. Then, the RAW264.7 cells were stimulated with lipopolysaccharide(LPS) for in vitro experiments. Cell viability was measured by MTT and ROS level was measured by DCFH-DA. NO content was measured by Griess assay, and IL-1β, IL-6, and TNF-α mRNA expression was detected by RT-PCR. The predicted targets were preliminarily verified by investigating the effect of Qilongtian Capsules on downstream cytokines. Eighty-four compounds were identified by UPLC-Q-TOF-MS/MS. Through database retrieval, 44 active components with 589 target genes were screened out. There were 560 ALI disease targets, and 65 intersection targets. PPI network topology analysis revealed 10 core targets related to ALI, including STAT3, JUN, VEGFA, CASP3, and MMP9. KEGG enrichment analysis showed that Qilongtian Capsules mainly exerted an anti-ALI effect by regulating cancer pathway, AGE-RAGE, MAPK, and JAK-STAT signaling pathways. The results of molecular docking showed that the main active components in Qilongtian Capsules, including crenulatin, ginsenoside F_1, ginsenoside Rb_1, ginsenoside Rd, ginsenoside Rg_1, ginsenoside Rg_3, notoginsenoside Fe, notoginsenoside G, notoginsenoside R_1, notoginsenoside R_2, and notoginsenoside R_3, had good binding affinities with the corresponding protein targets STAT3, JUN, VEGFA, CASP3, and MMP9. Cellular experiments showed that Qilongtian Capsules at 0.1, 0.25, and 0.5 mg·mL~(-1) reduced the release of NO, while Qilongtian Capsules at 0.25 and 0.5 mg·mL~(-1) reduced ROS production, down-regulated mRNA expression of IL-1β, IL-6, TNF-α, and inhibited the inflammatory cascade. In summary, Qilongtian Capsules may exert therapeutic effects on ALI through multiple components and targets.
Humans ; Tumor Necrosis Factor-alpha ; Ginsenosides ; Caspase 3 ; Matrix Metalloproteinase 9 ; Interleukin-6 ; Molecular Docking Simulation ; Network Pharmacology ; Reactive Oxygen Species ; Tandem Mass Spectrometry ; Acute Lung Injury/genetics* ; Capsules ; RNA, Messenger ; Drugs, Chinese Herbal/pharmacology*

Shenfu Injection(SFI) is praised for the high efficacy in the treatment of septic shock. However, the precise role of SFI in the treatment of sepsis-associated lung injury is not fully understood. This study investigated the protective effect of SFI on sepsis-associated lung injury by a clinical trial and an animal experiment focusing on the hypoxia-inducing factor-1α(HIF-1α)-mediated mitochondrial autophagy. For the clinical trial, 70 patients with sepsis-associated lung injury treated in the emergency intensive care unit of the First Affiliated Hospital of Zhengzhou University were included. The levels of interleukin(IL)-6 and tumor necrosis factor(TNF)-α were measured on days 1 and 5 for every patient. Real-time quantitative polymerase chain reaction(RT-qPCR) was performed to determine the mRNA level of hypoxia inducible factor-1α(HIF-1α) in the peripheral blood mononuclear cells(PBMCs). For the animal experiment, 32 SPF-grade male C57BL/6J mice(5-6 weeks old) were randomized into 4 groups: sham group(n=6), SFI+sham group(n=10), SFI+cecal ligation and puncture(CLP) group(n=10), and CLP group(n=6). The body weight, body temperature, wet/dry weight(W/D) ratio of the lung tissue, and the pathological injury score of the lung tissue were recorded for each mouse. RT-qPCR and Western blot were conducted to determine the expression of HIF-1α, mitochondrial DNA(mt-DNA), and autophagy-related proteins in the lung tissue. The results of the clinical trial revealed that the SFI group had lowered levels of inflammatory markers in the blood and alveolar lavage fluid and elevated level of HIF-1α in the PBMCs. The mice in the SFI group showed recovered body temperature and body weight. lowered TNF-α level in the serum, and decreased W/D ratio of the lung tissue. SFI reduced the inflammatory exudation and improved the alveolar integrity in the lung tissue. Moreover, SFI down-regulated the mtDNA expression and up-regulated the protein levels of mitochondrial transcription factor A(mt-TFA), cytochrome c oxidase Ⅳ(COXⅣ), HIF-1α, and autophagy-related proteins in the lung tissue of the model mice. The findings confirmed that SFI could promote mitophagy to improve mitochondrial function by regulating the expression of HIF-1α.
Humans ; Male ; Mice ; Animals ; Leukocytes, Mononuclear ; Mice, Inbred C57BL ; Lung/metabolism* ; Acute Lung Injury/drug therapy* ; Tumor Necrosis Factor-alpha/genetics* ; Sepsis/genetics* ; Hypoxia/pathology* ; Autophagy-Related Proteins ; Body Weight ; Drugs, Chinese Herbal

The purpose of this paper was to study the transcriptional regulation of nuclear respiratory factor 1 (NRF1) on nuclear factor kappa B (NF-κB), a key molecule in lipopolysaccharide (LPS)-induced lung epithelial inflammation, and to clarify the mechanism of NRF1-mediated inflammatory response in lung epithelial cells. In vivo, male BALB/c mice were treated with NRF1 siRNA, followed with LPS (4 mg/kg) or 0.9% saline through respiratory tract, and sacrificed 48 h later. Expression levels of NRF1, NF-κB p65 and its target genes were detected by Western blot and real-time PCR. Nuclear translocation of NRF1 or p65 was measured by immunofluorescent technique. In vitro, L132 cells were transfected with NRF1 siRNA or treated with BAY 11-7082 (5 μmol/L) for 24 h, followed with treatment of 1 mg/L LPS for 6 h. Cells were lysed for detections of NRF1, NF-κB p65 and its target genes as well as the binding sites of NRF1 on RELA (encoding NF-κB p65) promoter by chromatin immunoprecipitation assay (ChIP). Results showed that LPS stimulated NRF1 and NF-κB p65. Pro-inflammatory factors including interleukin-1β (IL-1β) and IL-6 were significantly increased both in vivo and in vitro. Obvious nuclear translocations of NRF1 and p65 were observed in LPS-stimulated lung tissue. Silencing NRF1 resulted in a decrease of p65 and its target genes both in vivo and in vitro. In addition, BAY 11-7082, an inhibitor of NF-κB, significantly repressed the inflammatory responses induced by LPS without affecting NRF1 expression. Furthermore, it was proved that NRF1 had three binding sites on RELA promoter region. In summary, NRF1 is involved in LPS-mediated acute lung injury through the transcriptional regulation on NF-κB p65.
Acute Lung Injury/genetics* ; Animals ; Lipopolysaccharides/pharmacology* ; Male ; Mice ; NF-kappa B/metabolism* ; Nuclear Respiratory Factor 1/genetics* ; RNA, Small Interfering ; Transcription Factor RelA/metabolism*