Lung Tissues Of Mice Research Articles

Treatment of silicosis with quercetin depolarizing macrophages via inhibition of mitochondrial damage-associated pyroptosis

Macrophage polarization facilitates the inflammatory response and intensified fibrosis in the silicosis microenvironment by a mechanism related to macrophage pyroptosis, although the upstream target remains poorly defined. Currently, there are few reports on the development of drugs that alleviate macrophage polarization by dampening pyroptosis. The present study aims to explore the mechanics of silica mediating macrophage polarization and to investigate whether quercetin (Que) can depolarize macrophages with this mechanism. Silica processing led to prominent M1 polarization of macrophages. Additionally, significant macrophage polarization could be detected in the lung tissue of mice with airway-perfused silica. Further investigation turned out that pronounced mitochondria damage, mtDNA cytoplasmic ectomy, and pyroptosis occurred in response to silica. Nevertheless, Que treatment could effectively attenuate silica-induced mitochondria damage and pyroptosis as demonstrated in vitro and in vivo. Further exploration presented Que could bind to TOM70 and restore silica-induced mitochondrial damage. More importantly, the M1 polarization of macrophage was depressed with the co-treatment of Que and silica, wherein the inflammatory response and pulmonary fibrosis were also mitigated without obvious damage to vital organs. In conclusion, these findings proved that silica leads to mitochondrial damage, thereby evoking pyroptosis and promoting macrophage M1 polarization. Que could bind to TOM70 and restore its function, suppressing mitochondrial damage and pyroptosis, and depolarizing macrophages to reduce fibrosis, which provides a promising strategy for silicosis treatment in the future.

Preliminary proteomic analysis of mouse lung tissue treated with cyclophosphamide and Venetin-1

Cyclophosphamide (CPAm) is a widely used chemotherapeutic agent that exhibits potent anti-cancer properties but is often associated with debilitating side effects. Despite its efficacy, the management of CPAm-induced toxicities remains a significant clinical challenge. There has been growing interest in exploring complementary and alternative therapies to mitigate these adverse effects in recent years, and this may be a chance for the earthworm-derived preparation, Venetin-1. Its rich composition of bioactive compounds has demonstrated promising pharmacological properties, including anti-inflammatory, antioxidant, and immunomodulatory effects. These properties suggest its potential to counteract various systemic toxicities induced by CPAm. We conducted a comprehensive study to investigate the effect of Venetin-1 on cyclophosphamide-induced toxicity. Mice were administered CPAm for four days, followed by application of the earthworm preparation in two doses (50 mg/kg and 100 mg/kg b.w). Importantly, the preparation did not cause any side effects in all mice, ensuring the safety of the intervention. We then determined global changes in the proteome using proteomics and quantitative SWATH-MS analysis, which is a robust and reliable method. This allowed us to identify up- and downregulated proteins in each studied group, providing valuable insights into the mechanism of action of Venetin-1. As shown by the results, Venetin-1 had a significant effect on the proteome of mouse lung tissue. It was possible to determine quantitative changes in 400 proteins, and the analysis after administration of Venetin-1 showed a change in the global proteomic profile from upregulated to down-regulated. The stimulating properties of the preparation concerning the complement system were also confirmed in a separate validation experiment. Venetin-1 shows promise in reducing the harmful effects of cyclophosphamide on lung tissue. It encourages tissue regeneration, reduces inflammation, supports autophagy, and boosts the immune system. However, more research is needed to thoroughly elucidate and describe the benefits of Venetin-1.

Effect of leucine on mitochondria and oxidative stress to reduce virulence and pathogenicity of Acinetobacter baumannii

Elucidating the virulence mechanisms of A. baumannii is essential for developing strategies to mitigate pathogenicity. Although high-virulent strains are associated with increased mortality rate in severely infected patients, the underlying mechanisms remains not well understood. Our analysis revealed leucine as a pivotal biomarker, with the 11dP and paaK being significant contributors to virulence. The ATP-dependent activity and antioxidant activity were identified as the most important pathways in distinguishing the virulence of A. baumannii. Exogenous leucine was found to modulate mitochondria dysfunction and oxidative stress, thereby diminishing the pathogenicity of A. baumannii towards Beas 2B cells. Moreover, leucine reduced the virulence of A. baumannii to Galleria mellonella (G. mellonella) and alleviated pathological damage to lung tissues in mice. Our study offers a novel treatment strategy based on metabolomics, which may assist in the exploration and management of infections caused by highly virulent pathogens. It sets a new course for reducing the impact of highly virulent A. baumannii infections and has significant implications for the development of future therapeutic interventions.

MiR-125b-5p alleviates pulmonary fibrosis by inhibiting TGFβ1-mediated epithelial-mesenchymal transition via targeting BAK1

This study explores the role and potential mechanisms of microRNA-125b-5p (miR-125b-5p) in pulmonary fibrosis (PF). PF is a typical outcome of many chronic lung diseases, with poor prognosis and the lack of appropriate medical treatment because PF’s molecular mechanisms remain poorly understood. In this study, using in vitro and in vivo analyses, we find that miR-125b-5p is likely a potent regulator of lung fibrosis. The findings reveal that, on the one hand, miR-125b-5p not only specifically decreases in the epithelial-mesenchymal transition (EMT) of lung epithelial cells, but also shows a downregulation trend in the lung tissues of mice with PF. On the other hand, overexpression of miR-125b-5p on the cellular and animal levels downregulates EMT and fibrotic phenotypes, respectively. To clarify the molecular mechanism of the “therapeutic” effect of miR-125b-5p, we use the target prediction tool combined with a dual luciferase assay and complete a rescue experiment by constructing the overexpression vector of the target gene Bcl-2 homologous antagonist/ killer (BAK1), thus confirming that miR-125b-5p can effectively inhibit EMT and fibrosis process by targeting BAK1 gene. MiR-125b-5p inhibits the EMT in lung epithelial cells by negatively regulating BAK1, while overexpression of miR-125b-5p can alleviate lung fibrosis. The findings suggest that MiR-125b-5p/BAK1 can serve as a potential treatment target for PF.Graphical abstract

Novel TSPO Ligand 2-Cl-MGV-1 Can Counteract Lipopolysaccharide Induced Inflammatory Response in Murine RAW264.7 Macrophage Cell Line and Lung Models.

We assessed the anti-inflammatory activity of the TSPO ligand 2-Cl-MGV-1. Lipopolysaccharide (LPS) was used to induce inflammatory response in a murine RAW264.7 macrophage model (LPS: 100 ng/mL) and a mouse model (C57BL/6) of lung inflammation (LPS: 5 mg/kg). In the macrophage model, the presence of 2-Cl-MGV-1 (25 µM) caused the LPS-induced elevation in nitrite levels to decrease by 70% (p < 0.0001) and interleukin (IL)-6 by 50% (p < 0.05). In the mouse model, 2-Cl-MGV-1, administered 30 min before, or co-administered with, an LPS injection, significantly inhibited the elevation in serum IL-5 levels (both by 65%; p < 0.001 and p < 0.01, respectively). 2-Cl-MGV-1 administration to mice 30 min before LPS injection and 1 h thereafter significantly inhibited the elevation in IL-1β serum levels (both by 63%, p < 0.005). IL-6 elevation was inhibited by 73% (p < 0.005) when 2-Cl-MGV-1 was administered 30 min before LPS, by 60% (p < 0.05) when co-administered with LPS, and by 64% (p < 0.05) when administered 1 h after LPS. All cytokine assessments were conducted 6 h post LPS injection. Histological analyses showed decreased leukocyte adherence in the lung tissue of the ligand-treated mice. 2-Cl-MGV-1 administration 30 min prior to exposure to LPS inhibited inflammation-induced open field immobility. The beneficial effect of 2-Cl-MGV-1 suggests its potential as a therapeutic option for inflammatory diseases.

Upregulated DNMT3a coupling with inhibiting p62-dependent autophagy contributes to NNK tumorigenicity in human bronchial epithelial cells

NNK, formally known as 4-(methyl nitrosamine)-1-(3-pyridyl)-1-butanoe, is a potent chemical carcinogen prevalent in cigarette smoke and is a key contributor to the development of human lung adenocarcinomas. On the other hand, autophagy plays a complex role in cancer development, acting as a "double-edged sword" whose impact varies depending on the cancer type and stage. Despite this, the relationship between autophagy and NNK-induced lung carcinogenesis remains largely unexplored. Our current study uncovers a marked reduction in p62 protein expression in both lung adenocarcinomas and lung tissues of mice exposed to cigarette smoke. Interestingly, this reduction appears to be contingent upon the activity of extrahepatic cytochrome P450 (CYP450), revealing that NNK metabolic activation by CYP450 enzyme escalates its potential to induce p62 downregulation. Further mechanistic investigations reveal that NNK suppresses autophagy by accelerating the degradation of p62 mRNA, thereby promoting the malignant transformation of human bronchial epithelial cells. This degradation process is facilitated by the hypermethylation of the Human antigen R (HuR) promoter, resulting in the transcriptional repression of HuR - a key regulator responsible for stabilizing p62 mRNA through direct binding. This hypermethylation is triggered by the activation of ribosomal protein S6, which is influenced by NNK exposure and subsequently amplifies the translation of DNA methyltransferase 3 alpha (DNMT3a). These findings provide crucial insights into the nature of p62 in both the development and potential treatment of tobacco-related lung cancer.

Ruhao Dashi granules exert therapeutic effects on H1N1 influenza virus infection by altering intestinal microflora composition.

Antiviral medications for influenza could be ineffective due to the emergence of resistant influenza virus strains. Ruhao Dashi (RHDS) granules possess anti-inflammatory and antibacterial effects. The present study aimed to determine the efficacy of RHDS granules in treating influenza-infected mice and the mechanism underlying this treatment as well as its effect on the intestinal flora composition of the infected mice. The HPLC-UV method was used to identify the active components of RHDS granules. ICR mice were infected with influenza A virus (IAV) H1N1 subtype through a nasal drip. After the influenza mice model was successfully established, the pathological changes in the lungs were observed for 5 days after gavage treatment with 0.9% sterile saline and low, medium, and high doses (0.07, 0.14, and 0.28 g/mL, respectively) of RHDS granules. The serum levels of the cytokines IL-6 and TNF-α and sIgA were detected by ELISA. Real-time fluorescence quantitative PCR and western blotting assay were performed to determine the expression levels of the tight junction (TJ) proteins claudin-1, occludin, and zonula occludens-1 (ZO-1) in colon tissues. Furthermore, 16S rRNA gene sequencing of feces samples was conducted to assess the effect of RHDS granules on the gut microbiota. RHDS granules exerted a protective effect on the lung tissues of IAV-infected mice; moreover, the granules reduced the synthesis of proinflammatory cytokines and increased the relative expression levels of claudin-1, occludin, and ZO-1 in colon tissues. Furthermore, RHDS granule treatment increased the relative abundance of Lactobacillus, Akkermansia, and Faecalibaculum and decreased the relative abundance of Muribaculaceae; thus, RHDS granules could stabilize the intestinal microbiota to some extent. RHDS granules exert a therapeutic effect on IAV-infected mice probably by modifying the structural composition of their intestinal microbiota.

Ozone-Induced Lung Injury are Mediated Via PPAR-Mediated Ferroptosis in Mice.

In recent years, the concentration of PM2.5 in China has decreased, while the concentration of ozone remains rising. Exposure to ozone contributes to respiratory illnesses; however, little is known about the underlying molecular mechanisms. The present study established an ozone-induced lung injury mice model to investigate potential molecular biomarkers and toxic mechanisms. Collected and analyzed the ozone pollution data in Xinxiang city from 2015 to 2022. At the same time, 24 male C57BL/6 mice were randomly assigned to control group and ozone exposure group. The ozone exposure concentration is 1ppm, with 4h of daily exposure for 33 consecutive days. HE staining was used to assess lung histological alterations and lung injury. High-throughput sequencing performed on the lung tissues of mice was used to analyze the differential expressed genes and signal transduction pathways. Xinxiang city is suffering from ozone pollution, especially in summer. HE staining showed that the ozone exposure could induce obvious inflammatory cell infiltration, alveolar wall thickening, or fracture. Transcriptome data revealed that there is a 145 differentially expressed genes between two groups and the genes enriched in PPAR signaling pathway, ferroptosis. The pivotal genes in the PPAR pathway including Adipoq, Lpl, Pck1, and Plin1 expression were significantly reduced. Additionally, the expression of Acsl6 and Scl7a11, which are close to PPAR pathway and ferroptosis has decreased. Ozone exposure could disrupt the lipid metabolism balance via downregulating lipid peroxidation-related genes through the PPAR signaling pathway, which further induced lung cell ferroptosis and aggravated lung injury in mice.

Protective effect and mechanism of rapamycin on pulmonary fibrosis induced by Chlormethine in mice

To evaluate the therapeutic effect and mechanism of rapamycin (RAPA) on pulmonary fibrosis induced by chlormethine in C57BL/6N mice. Based on body weight, the 18-20 g C57BL/6N mice were randomly divided into five groups: control group, chlormethine group, chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, with ten mice in each group. Mice were put to death on the 21st day after the first administration of chlormethine. HE staining and Masson staining were used to observe the pathological changes and degree of fibrosis in the lung tissue of mice, and RT-PCR was used to detect collagen Ⅰ, E-cadherin, vimentin, and α-SMA mRNA expression. After 21 days of administration of chlormethine to mice, significant pulmonary fibrosis characteristics were observed in the lung tissue of the mice. Compared with the chlormethine group, the weight of mice in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, significantly increased (P<0.05). Compared with the chlormethine group, the expression of pulmonary fibrosis-related indicators (collagen Ⅰ, E-cadherin, vimentin, and α-SMA) significantly improved (P<0.05) in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group. Compared with the chlormethine group, the pathological changes and collagen deposition in the lung tissue of mice in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, were significantly improved. Transcriptome analysis of the lung tissue of mice revealed that RAPA treatment of chlormethine-induced pulmonary fibrosis might be related to NF-kappa B signaling pathway. Compared with the chlormethine group, the mRNA expression of p65 in the lung tissue of mice in the chlormethine+dexamethasone (1 mg/kg) group, chlormethine+RAPA (1 mg/kg) group and chlormethine+RAPA (2 mg/kg) group, significantly decreased (P<0.01). RAPA has a protective effect on pulmonary fibrosis induced by chlormethine in mice. Its efficacy is comparable to that of dexamethasone, which is currently being used in clinical practice. It is a new alternative therapy, and its mechanism may be related to inhibiting the activation of the NF-kappa B signaling pathway.

Cordyceps militaris Grown on Germinated Rhynchosia nulubilis (GRC) Encapsulated in Chitosan Nanoparticle (GCN) Suppresses Particulate Matter (PM)-Induced Lung Inflammation in Mice.

Cordyceps militaris grown on germinated Rhynchosia nulubilis (GRC) exerts various biological effects, including anti-allergic, anti-inflammatory, and immune-regulatory effects. In this study, we investigated the anti-inflammatory effects of GRC encapsulated in chitosan nanoparticles (CN) against particulate matter (PM)-induced lung inflammation. Optimal CN (CN6) (CHI: TPP w/w ratio of 4:1; TPP pH 2) exhibited a zeta potential of +22.77 mV, suitable for GRC encapsulation. At different GRC concentrations, higher levels (60 and 120 mg/mL) led to increased negative zeta potential, enhancing stability. The optimal GRC concentration for maximum entrapment (31.4 ± 1.35%) and loading efficiency (7.6 ± 0.33%) of GRC encapsulated in CN (GCN) was 8 mg/mL with a diameter of 146.1 ± 54 nm and zeta potential of +30.68. In vivo studies revealed that administering 300 mg/kg of GCN significantly decreased the infiltration of macrophages and T cells in the lung tissues of PM-treated mice, as shown by immunohistochemical analysis of CD4 and F4/80 markers. Additionally, GCN ameliorated PM-induced lung tissue damage, inflammatory cell infiltration, and alveolar septal hypertrophy. GCN also decreased total cells and neutrophils, showing notable anti-inflammatory effects in the bronchoalveolar lavage fluid (BALF) from PM-exposed mice, compared to GRC. Next the anti-inflammatory properties of GCN were further explored in PM- and LPS-exposed RAW264.7 cells; it significantly reduced PM- and LPS-induced cell death, NO production, and levels of inflammatory cytokine mRNAs (IL-1β, IL-6, and COX-2). GCN also suppressed NF-κB/MAPK signaling pathways by reducing levels of p-NF-κB, p-ERK, and p-c-Jun proteins, indicating its potential in managing PM-related inflammatory lung disease. Furthermore, GCN significantly reduced PM- and LPS-induced ROS production. The enhanced bioavailability of GRC components was demonstrated by an increase in fluorescence intensity in the intestinal absorption study using FITC-GCN. Our data indicated that GCN exhibited enhanced bioavailability and potent anti-inflammatory and antioxidant effects in cells and in vivo, making it a promising candidate for mitigating PM-induced lung inflammation and oxidative stress.

Sappanone A ameliorates acute lung injury through inhibiting the activation of the NF-κB signaling pathway

Acute lung injury (ALI) is a serious respiratory disease characterized by diffuse alveolar injury, and it has emerged as a major concern in clinical practice due to limited treatments. This study aimed to explore the pharmacological effects and regulatory mechanism of sappanone A (SA) on ALI. In vivo, mice were administered with SA followed by intratracheal injection of lipopolysaccharide (LPS) to establish an animal model of ALI. We observed that SA exerted comparable anti-inflammatory effects to dexamethasone, as evidenced by effectively mitigating histopathological abnormalities and suppressing the inflammatory response in the lung tissues of mice with ALI. RNA sequencing analysis revealed that SA significantly inhibited the activation of the nuclear factor kappa B (NF-κB) signaling pathway. In vitro, we found that SA protected BEAS-2B cells against LPS-induced cellular injury and reduced inflammatory cytokine generation. Furthermore, both in vivo and in vitro experiments demonstrated that SA effectively prevented LPS-induced oxidative stress and apoptosis. Consistent with the results of the RNA sequencing analysis, SA significantly inhibited the increased protein expressions of p105, p50, c-REL, as well as the ratios of p-p65/p65 and p-IκBα/IκBα in the lung tissues of mice with ALI and LPS-stimulated BEAS-2B cells. Additionally, SA inhibited the nuclear translocation of p65 in BEAS-2B cells stimulated with LPS. Importantly, specific blockade of the NF-κB signaling pathway using BAY11–7082 was identified to alleviate LPS-induced cellular injury in BEAS-2B cells. Collectively, these findings suggest that SA can ameliorate ALI, at least in part, through the inhibition of NF-κB signaling pathway activation.

Heparin-binding protein and sepsis-induced coagulopathy: Modulation of coagulation and fibrinolysis via the TGF-β signalling pathway

BackgroundHeparin-binding protein (HBP) levels have been linked to organ failure and may represent an inflammatory biomarker of sepsis. We found disseminated intravascular coagulation (DIC) is associated with higher HBP levels in patients and in in vivo and in vitro models. This prospective, single-center observational study investigated the effects and underlying mechanisms of HBP on the coagulation cascade in sepsis. Methods538 patients with sepsis from June 2016 to December 2019 were enrolled. Mechanisms underlying HBP and the coagulation system were investigated in human umbilical vein endothelial cells (HUVEC) and C57 mice. ResultsIncreased HBP was associated with sepsis-induced DIC. The optimal cutoff value was 37.5 ng/mL (sensitivity: 56 %, specificity: 65 %). Antithrombin-III (AT-III) activity, plasmin-a2 plasmin inhibitor complex (PIC), procalcitonin (PCT), hemoglobin, and HBP ≥37.5 ng/mL were associated with of DIC occurrence. In HUVECs &C57 mice models, Western blotting, qPCR, and immunohistochemistry analysis showed that the binding between HBP and TGF-β receptor 2 (TGFBR2) caused elevation of plasminogen activator inhibitor-1 (PAI-1) levels. Furthermore, we found that mice stimulated with HBP had higher levels of fibrinogen and D-dimer in the blood. HBP treatment caused the accumulation of fibrinogen in mice lung tissue. Treatment with TGFBR2-small interfering RNAs inhibited the effects. ConclusionPatients with sepsis having HBP ≥37.5 ng/mL at admission were more likely to develop DIC. HBP upregulates the expression of fibrinogen and PAI-1 via TGFBR2 and the TGF-β signalling pathway.

Human Umbilical Cord Mesenchymal Stem Cell Exosome-derived miR-335-5p Alleviated Lipopolysaccharide-induced Acute Lung Injury by Regulating the m6A Level of ITGβ4 Gene.

Acute lung injury (ALI) is a serious complication that may accompany severe pneumonia in children. Derived from human umbilical cord mesenchymal stem cell exosome (HucMSC-Exo) can contribute to the regeneration of damaged lung tissue. This study aims to investigate the impact of HucMSC-Exo on ALI and its potential mechanisms. Firstly, RT-qPCR was performed to assess the expression of miR-335-5p. Subsequently, Pearson correlation analysis was performed to examine the correlation between METTL14 and miR-335-5p, as well as the correlation between METTL14 and ITGβ4, while RNA immunoprecipitation (RIP) was used to determine the m6A modification level of ITGβ4. Additionally, molecular biology techniques were employed to evaluate the expression of glycolysis-related factors. Definitively, an LPS-induced ALI model was established to investigate the effect of miR-335-5p on mice lung tissue. miR-335-5p was found to be highly expressed in HucMSC-Exo. Transfection with miR-335-5p mimics resulted in increased glucose uptake. Pearson correlation analysis revealed a negative correlation between METTL14 and miR-335-5p, as well as between METTL14 and ITGβ4. The m6A level of ITGβ4 was elevated in ALI. Overexpression of METTL14 was found to reduce the expression of ITGβ4 and glucose levels, while overexpression of ITGβ4 reversed the effects of METTL14 overexpression. In vivo, results demonstrated that miR-335-5p could improve the extent of lung tissue lesions and reduce glycolytic levels. This study revealed the mechanism by which miR-335-5p derived from HucMSC-Exo could alleviate LPS-induced ALI by regulating the m6A modification of ITGβ4, providing a new direction for the treatment of ALI.

Targeting TLR4 and regulating the Keap1/Nrf2 pathway with andrographolide to suppress inflammation and ferroptosis in LPS-induced acute lung injury

Acute lung injury (ALI) is a severe inflammatory condition with a high mortality rate, often precipitated by sepsis. The pathophysiology of ALI involves complex mechanisms, including inflammation, oxidative stress, and ferroptosis, a novel form of regulated cell death. This study explores the therapeutic potential of andrographolide (AG), a bioactive compound derived from Andrographis, in mitigating Lipopolysaccharide (LPS)-induced inflammation and ferroptosis. Our research employed in vitro experiments with RAW264.7 macrophage cells and in vivo studies using a murine model of LPS-induced ALI. The results indicate that AG significantly suppresses the production of pro-inflammatory cytokines and inhibits ferroptosis in LPS-stimulated RAW264.7 cells. In vivo, AG treatment markedly reduces lung edema, decreases inflammatory cell infiltration, and mitigates ferroptosis in lung tissues of LPS-induced ALI mice. These protective effects are mediated via the modulation of the Toll-like receptor 4 (TLR4)/Kelch-like ECH-associated protein 1(Keap1)/Nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. Molecular docking simulations identified the binding sites of AG on the TLR4 protein (Kd value: -33.5 kcal·mol-1), and these interactions were further corroborated by Cellular Thermal Shift Assay (CETSA) and SPR assays. Collectively, our findings demonstrate that AG exerts potent anti-inflammatory and anti-ferroptosis effects in LPS-induced ALI by targeting TLR4 and modulating the Keap1/Nrf2 pathway. This study underscores AG's potential as a therapeutic agent for ALI and provides new insights into its underlying mechanisms of action.

Qingfei Huoxue Decoction and Its Active Component Narirutin Alleviate LPS-Induced Acute Lung Injury by Regulating TLR4/NF-κB Pathway Mediated Inflammation.

Acute lung injury (ALI) is a life-threatening clinical syndrome with high mortality. Currently, the safe and effective therapies for ALI patients are still limited. Qingfei Huoxue decoction (QFHXD) is a hospital agreement prescription for treating pulmonary diseases and displays a remarkable efficacy. However, the pharmacological effect of QFHXD on preventing lipopolysaccharide (LPS)-induced ALI has yet to be reported, let alone questions of potential molecular mechanisms and anti-ALI active substances. To answer the above-mentioned questions, histopathological observation and kit detection were performed to estimate the protective effect of QFHXD pretreatment against LPS-induced ALI. Based on comprehensive chemical profiling of QFHXD, a network pharmacology strategy and experimental validation were integrated to elucidate the underlying functional mechanisms. The potential anti-ALI active components were identified by molecular docking. The anti-ALI activity of narirutin and its anti-inflammatory mechanism were further validated using animal and molecular experiments. Pretreatment with different doses of QFHXD effectively mitigated histopathological lesions and systemic inflammation caused by LPS stimulation. A detailed analysis of established compound-target-disease network revealed the strong correlation between anti-ALI action of QFHXD and inflammatory mechanisms. Compared with the model group, QFHXD intervention markedly restrained the abnormally increased transcription and protein levels of pro-inflammatory factors (TLR4, NF-κB, IL-6, IL-1β, and TNF-α) in lung tissues of ALI mice. The results of molecular docking highlighted the anti-ALI potential of narirutin targeting to TLR4 and NF-κB p65. In addition to the protective effect of narirutin on suppressing LPS-induced pathological changes, we found that narirutin pretreatment effectively normalized the disordered protein levels of above pro-inflammatory factors of ALI mice. These interesting findings indicate the beneficial effects of QFHXD and its active component narirutin against ALI partly via regulating TLR4/NF-κB mediated inflammation. This work contributes to the development of novel medications for ALI patients.

COPD-Like Phenotypes in TBC-Treated Mice Can be Effectively Alleviated via Estrogen Supplement.

Tris(2,3-dibromopropyl) isocyanurate (TBC), recognized as an endocrine disruptor, can cause inflammatory injury to the lung tissue of mice. To investigate the specific respiratory effects of TBC, male C57BL/6J mice were administered a daily dose of 20 mg/kg of TBC over 14 days. Postexposure, these mice developed chronic obstructive pulmonary disease (COPD)-like symptoms characterized by inflammatory lung damage and functional impairment. In light of the antiestrogenic properties of TBC, we administrated estradiol (E2) to investigate its potential protective role against TBC-induced damage and found that the coexposure of E2 notably mitigated the COPD-like phenotypes. Immunohistochemical analysis revealed that TBC exposure reduced estrogen receptor alpha (ERα) expression and increased nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) expression, while E2 treatment rebalanced the expression levels of ERα and NF-κB to their normative states. Our findings indicate that TBC, as an antiestrogenic agent, may contribute to the pathogenesis of COPD through an ERα-mediated inflammatory pathway, but that E2 treatment could reverse the impairment, providing a potentially promising remedial treatment. Given the lung status as a primary target of air pollution, the presence of antiestrogenic compounds like TBC in atmospheric particulates presents a significant concern, with the potential to exacerbate respiratory conditions such as COPD and pneumonia.

Low dose methotrexate impaired T cell transmigration through down-regulating CXCR4 expression in rheumatoid arthritis (RA)

BackgroundCXC chemokine CXCL12 is involved in the pathological development of rheumatoid arthritis (RA) through abnormal migration of peripheral immune cells in the joint. Although low dose methotrexate (MTX) is clinically used to treat RA patients, CXCL12 signaling responses to MTX-mediated treatments is still not well understood.MethodsIn this study, we examined the expression of CXCR4 (cognatic receptor for CXCL12) in peripheral T cells from RA patients and arthritis mice models received from low dose MTX therapies. The effects of low dose MTX on CXCR4 were further determined via both in vitro CD3+ T cells and Cxcr4 conditional knockout (CKO) arthritis mice models.ResultsOur clinical data shows that low dose MTX treatment was clinically associated with down-regulated expression of chemokine receptor CXCR4 on patient peripheral T cells. In vitro, low dose MTX significantly decreased cell transmigration through down-regulated CXCR4’s expression in CD3+ T cells. Consistently, CD3+ T cells treated with low dose MTX demonstrated an increased genomic hypermethylation across the promoter region of Cxcr4 gene. Furthermore, our preclinical studies showed that low dose MTX-mediated downregulation of CXCR4 significantly improved the pathological development in mouse arthritis models. Conditional disruption of the Cxcr4 gene in peripheral immune cells potentially alleviated inflammation of joints and lung tissue in the arthritis mice, though genetic modification itself overall did not change their clinical scores of arthritis, except for a significant improvement on day 45 in CXCR4 CKO arthritis mice models during the recovery phase.ConclusionOur findings suggest that the effect of low dose MTX treatment could serve to eliminate inflammation in RA patients through impairment of immune cell transmigration mediated by CXCR4.

Epigenetic mechanism of EZH2-mediated histone methylation modification in regulating ferroptosis of alveolar epithelial cells in sepsis-induced acute lung injury.

Sepsis-induced acute lung injury (SI-ALI) leads to significant deaths in critically ill patients worldwide. This study explores the mechanism of EZH2 regulating ferroptosis of alveolar epithelial cells (AECs) in SI-ALI. In vitro cell model and in vivo mouse lung injury model of sepsis were established. EZH2 expression in lung tissues was intervened by sh-EZH2, followed by H&E staining observation of lung tissue pathological changes. EZH2, H3K27me3, USP10, GPX4, and ACSL4 expressions were determined by qRT-PCR or Western blot. ROS, GSH, and iron ion levels were detected using fluorescent labeling and reagent kits, respectively. ChIP analyzed the enrichment of EZH2 and H3K27me3 on USP10 promoter. The binding between USP10 and GPX4, and the ubiquitination level of GPX4 were detected using Co-IP. EZH2 was highly expressed in lung tissues of SI-ALI mice. EZH2 silencing alleviated ALI and ferroptosis of AECs; EZH2 increased the H3K27me3 level on USP10 promoter through histone methylation. USP10 stabilized GPX4 protein expression through ubiquitination; inhibition of USP10 partially reversed the inhibitory effect of EZH2 silencing on ferroptosis of AECs. In conclusion, EZH2 depresses USP10 expression by promoting histone H3K27me3 modification on USP10 promoter, thereby enhancing ubiquitination degradation of GPX4 and ultimately facilitating ferroptosis of AECs in sepsis.

Nobiletin, as a Novel PDE4B Inhibitor, Alleviates Asthma Symptoms by Activating the cAMP-PKA-CREB Signaling Pathway.

Asthma is a chronic airway inflammation that is considered a serious public health concern worldwide. Nobiletin (5,6,7,8,3',4'-hexamethyl flavonoid), an important compound isolated from several traditional Chinese medicines, especially Citri Reticulatae Pericarpium, is widely used for a number of indications, including cancer, allergic diseases, and chronic inflammation. However, the mechanism by which nobiletin exerts its anti-asthmatic effect remains unclear. In this research, we comprehensively demonstrated the anti-asthmatic effects of nobiletin in an animal model of asthma. It was found that nobiletin significantly reduced the levels of inflammatory cells and cytokines in mice and alleviated airway hyperresponsiveness. To explore the target of nobiletin, we identified PDE4B as the target of nobiletin through pharmacophore modeling, molecular docking, molecular dynamics simulation, SPR, and enzyme activity assays. Subsequently, it was found that nobiletin could activate the cAMP-PKA-CREB signaling pathway downstream of PDE4B in mouse lung tissues. Additionally, we studied the anti-inflammatory and anti-airway remodeling effects of nobiletin in LPS-induced RAW264.7 cells and TGF-β1-induced ASM cells, confirming the activation of the cAMP-PKA-CREB signaling pathway by nobiletin. Further validation in PDE4B-deficient RAW264.7 cells confirmed that the increase in cAMP levels induced by nobiletin depended on the inhibition of PDE4B. In conclusion, nobiletin exerts anti-asthmatic activity by targeting PDE4B and activating the cAMP-PKA-CREB signaling pathway.

Anti-Inflammatory Effects of Lupeol as a Candidate for New Drug Development.

This study explores the anti-inflammatory properties of lupeol, a notable phytosterol found in various medicinal plants, highlighting its potential as a candidate for new drug development. We examined the effects of lupeol on heme oxygenase (HO)-1, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS) in lipopolysaccharide (LPS)-stimulated human umbilical vein endothelial cells (HUVECs), as well as its impact on inflammatory markers in the lung tissues of LPS-challenged mice. Lupeol treatment enhanced HO-1 production, inhibited nuclear factor (NF)-κB activity, and reduced levels of COX-2/prostaglandin E2 (PGE2) and iNOS/nitric oxide (NO). In addition, lupeol decreased the phosphorylation of signal transducer and activator of transcription 1 (STAT-1) and promoted the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2), enhancing its binding to the anti-oxidant response element (ARE) and subsequently reducing interleukin (IL)-1β expression. Invivo, lupeol significantly lowered iNOS expression and tumor necrosis factor (TNF)-α levels in bronchoalveolar lavage fluid from LPS-treated mice. These findings suggest that lupeol exerts its anti-inflammatory effects by modulating key signaling pathways, positioning it as a promising candidate for the development of novel therapeutics targeting pathological inflammation.