Model Of Lung Inflammation Research Articles

Milonine attenuates the lipopolysaccharide-induced acute lung injury in mice by modulating the Akt/NF-κB signaling pathways.

Acute lung injury is an inflammation that triggers acute respiratory distress syndrome with perialveolar neutrophil infiltration, alveolar-capillary barrier damage, and lung edema. Activation of the toll-like receptor 4 complex (TLR4/MD2) and its downstream signaling pathways are responsible for the cytokine storm and cause alveolar damage. Due to the complexity of this pulmonary inflammation, a defined pharmacotherapy has not been established. Thus, this study evaluated the anti-inflammatory potential of milonine, an alkaloid of Cissampelos sympodialis Eichl, in an experimental model of lung inflammation. BALB/c mice were lipopolysaccharide-challenged and treated with milonine at 2.0 mg/kg. Twenty-four hours later, the bronchoalveolar fluid, peripheral blood, and lungs were collected for cellular and molecular analysis. The milonine treatment decreased the cell migration (mainly neutrophils) to the alveoli, the pulmonary edema, and the cytokine levels (IL-1β, IL-6, TNF-α). The systemic IL-6 level was also reduced. The milonine docking analysis demonstrated hydrophobic interaction at TLR4/MD2 groove with Ile124 and Phe126 amino acids. Indeed, the alkaloid downregulated the kinase-Akt and NF-κB through TLR4/MD2. Therefore, milonine is an effective inflammatory modulator being a potential molecule for the treatment of lung inflammation.

Ncf1 Governs Immune Niches in the Lung to Mediate Pulmonary Inflammation in Mice.

Neutrophil cytosolic factor 1 (Ncf1) is a major genetic factor associated with autoimmune diseases and has been identified as a key player in autoimmune mediated inflammation. We addressed the role of Ncf1 in an antigen-induced pulmonary inflammation model, and found that the Ncf1m1j mutation, causing a deficient reactive oxygen species response, alleviated disease. The Ncf1m1j mutation was associated with a reduced inflammatory cell infiltration in airways, but had limited effect on mucus secretion, antibody production and lung fibrosis. The disease remission in the Ncf1 mutated mice was reversed when functional Ncf1 was transgenically expressed in alveolar macrophages, suggesting that the cellular inflammation was depended on functional Ncf1 in alveolar macrophages. By determining cytokine and chemokine profiles in lung and serum, we found that Ncf1 deficiency allowed an increased expression of Th1 cytokines, including TNF-α, IFN-γ and IL-12. Since also epithelial cytokines were found to be regulated by Ncf1, we tested the effect of Ncf1 in IL-33 and IL-25 induced lung inflammation models. Mice with the Ncf1m1j mutation showed less sensitivity to IL-33, but not IL-25, induced lung inflammation, in a macrophage independent manner. The mice with deficient Ncf1 showed a reduced eosinophil infiltration and group 2 innate lymphoid cell (ILC2) activation. The production of IFN-γ in CD4+ T cells was increased, whereas IL-5 and IL-13 in ILC2 were decreased. Importantly, anti-IFN-γ antibody treatment of Ncf1 deficient mice increased eosinophil infiltration and rescued ILC2 activation in the lung. We conclude that Ncf1 deficiency enhances Th1 response, deactivates ILC2, and protects against pulmonitis.

Anti-inflammatory effect of Helix aspersa extracts in sephadex-induced model of lung inflammation: possible modulation of neutrophils

The focus of our study is to compare the anti-inflammatory effect of extracts prepared from Algerian mollusk called Helix ,on induced lung inflammation in rats: aqueous AE, HE and organic OE extracts. Animals were classified into six groups: control group T was instilled with NaCl (0.9%) in the trachea, negative control group was instilled with in trachea (5mg//Kg), positive control group was instilled with and treated with an anti-inflammatory drug, groups SAE, SHE and SOE were instilled with and treated with aqueous, and organic extracts respectively (4mg//Kg). 24h after instillation, we sacrificed animals, blood samples and fluid lavage (BALF) were collected. Lungs were for investigation. We measured activity (MPO) in BALF. Results showed induces a massive in lungs. HE and OE decreased leukocyte count in BALF and blood. AE increased leukocyte count in blood and decreased it in BALF. The three extracts decreased MPO activity in BALF, reduced number of inflammatory cells in the and protected lung from beads injuries. Both AE and HE reduced edema in lung. We conclude that treatment with Helix had an anti-inflammatory effect on inflammation.

A peptide derived from chaperonin 60.1, IRL201104, inhibits LPS-induced acute lung inflammation.

Chaperonin 60.1 (Cpn60.1) is a protein derived from Mycobacterium tuberculosis that has been shown, along with its peptide fragment IRL201104, to have beneficial effects in models of allergic inflammation. To further investigate the anti-inflammatory properties of Cpn60.1 and IRL201104, we have investigated these molecules in a model of nonallergic lung inflammation. Mice were treated with Cpn60.1 (0.5-5,000 ng/kg) or IRL201104 (0.00025-2.5 ng/kg), immediately before intranasal instillation of bacterial lipopolysaccharide (LPS). Cytokine levels and cell numbers in mouse bronchoalveolar lavage (BAL) fluid were measured 4 h after LPS administration. In some experiments, mice were depleted of lung-resident phagocytes. Cells from BAL fluid were analyzed for inflammasome function. Human umbilical vein endothelial cells (HUVECs) were analyzed for adhesion molecule expression. Human neutrophils were analyzed for integrin expression, chemotaxis, and cell polarization. Cpn60.1 and IRL201104 significantly inhibited neutrophil migration into the airways, independently of route of administration. This effect of the peptide was absent in TLR4 and annexin A1 knockout mice. Intravital microscopy revealed that IRL201104 reduced leukocyte adhesion and migration into inflamed tissues. However, IRL201104 did not significantly affect adhesion molecule expression in HUVECs or integrin expression, chemotaxis, or polarization of human neutrophils at the studied concentrations. In phagocyte-depleted animals, the anti-inflammatory effect of IRL201104 was not significant. IRL201104 significantly reduced IL-1β and NLRP3 expression and increased A20 expression in BAL cells. This study shows that Cpn60.1 and IRL201104 potently inhibit LPS-induced neutrophil infiltration in mouse lungs by a mechanism dependent on tissue-resident phagocytes and to a much lesser extent, the proresolving factor annexin A1.

Dietary New Zealand propolis supplementation reduced proinflammatory cytokines in an acute mouse model of air pollution exposure, without impacting on immune cell infiltration or lung function

• Propolis reduced urban dust-induced lung TNFα, IL-4, and IL-6 production in mice. • Propolis did not alter urban dust-induced immune cell infiltration into mice lungs. • Propolis did not alter urban dust-induced airways constriction in mice. • This suggests that Propolis only partially reduces inflammatory responses in an urban dust mouse model. Air pollution is estimated to cause 7 million annual deaths globally. Our aim was to determine if dietary propolis consumption could prevent the immune and functional damage in a mouse model of acute urban dust exposure. Female C57BL/6J mice were challenged three times with intranasal urban dust over seven days which significantly increased proinflammatory cytokines and immune cells in the lung 24 h post final challenge. Dietary New Zealand propolis (2%) with gamma cyclodextrin supplementation reduced urban dust-induced lung TNFα, IL-4, and IL-6 cytokine production; but did not alter immune cell infiltration into the lung, or lung function outcomes. This suggests that daily consumption of 8% propolis with gamma cyclodextrin supplemented food was sufficient to reduce urban dust pollution-induced proinflammatory cytokine production but was not sufficient to prevent immune cell recruitment into the lung or lung function decline in a murine model of lung inflammation.

Therapeutic Effects of the Bcl-2 Inhibitor on Bleomycin-induced Pulmonary Fibrosis in Mice.

Idiopathic pulmonary fibrosis (IPF) is a distressing lung disorder with poor prognosis and high mortality rates. Limited therapeutic options for IPF is a major clinical challenge. Well-known for its anti-apoptotic properties, B-cell lymphoma 2 (Bcl-2) plays a critical role in the pathology of malignancies and inflammatory diseases, including IPF. In this study, we aimed to investigate the therapeutic effect of a Bcl-2 homology domain 3 mimetic inhibitor, ABT-199, on bleomycin (BLM)-induced pulmonary fibrosis in mice, and explore possible underlying mechanism. The lung inflammation and fibrosis model was established by intratracheal instillation of a single dose of BLM. We observed elevated Bcl-2 in the alveolar macrophages and fibroblasts derived from BLM-instilled mice from day 7. Further, we obtained in vivo evidence that early therapeutic treatment with Bcl-2 inhibitor ABT-199 from day 3, and late treatment from day 10, both alleviated airway inflammation and lung fibrosis induced by BLM. Our data suggest that ABT-199 might be an effective antifibrotic agent that interferes with profibrogenic cells, which may be a promising therapy in the treatment of clinical IPF patients.

Absence of pro-survival A1 has no impact on inflammatory cell survival in vivo during acute lung inflammation and peritonitis.

Inflammation is a natural defence mechanism of the body to protect against pathogens. It is induced by immune cells, such as macrophages and neutrophils, which are rapidly recruited to the site of infection, mediating host defence. The processes for eliminating inflammatory cells after pathogen clearance are critical in preventing sustained inflammation, which can instigate diverse pathologies. During chronic inflammation, the excessive and uncontrollable activity of the immune system can cause extensive tissue damage. New therapies aimed at preventing this over-activity of the immune system could have major clinical benefits. Here, we investigated the role of the pro-survival Bcl-2 family member A1 in the survival of inflammatory cells under normal and inflammatory conditions using murine models of lung and peritoneal inflammation. Despite the robust upregulation of A1 protein levels in wild-type cells upon induction of inflammation, the survival of inflammatory cells was not impacted in A1-deficient mice compared to wild-type controls. These findings indicate that A1 does not play a major role in immune cell homoeostasis during inflammation and therefore does not constitute an attractive therapeutic target for such morbidities.

HMGB1 could restrict 1,3-β-glucan induced mice lung inflammation by affecting Beclin1 and Bcl2 interaction and promoting the autophagy of epithelial cells

Fungi were microorganisms that are ubiquitous in a variety of environments. Inhalation of fungi-contaminated organic dust led to hypersensitivity pneumonitis and might eventually cause irreversible pulmonary fibrosis. Studies showed that maintaining the homeostasis of epithelial cells was vital for defending the exogenous fungi invasion. HMGB1-dependent autophagy played a critical role in maintaining cell homeostasis in multiple inflammatory diseases. However, the actual role of HMGB1-dependent autophagy in hypersensitivity pneumonitis was unclear. In our study, mice were exposed to 0.3 mg/50 μL 1,3-β-glucan solution by intratracheal instillation to set up the lung inflammation model. To investigate the role of HMGB1-dependent autophagy in 1,3-β-glucan induced lung inflammation, AAV-sh-HMGB1 was intratracheally injected to silence HMGB1 in the lung. Our finding suggested that silencing HMGB1 could aggravate the 1,3-β-glucan induced lung inflammation by inhibiting the autophagy of epithelial cells. And ubiquitination of Beclin1 contributed to decreasing the interaction of Beclin1 and Bcl2, which might be a key regulatory mechanism of HMGB1 on 1,3-β-glucan induced autophagy.

Angiotensin-(1-7)/Mas receptor modulates anti-inflammatory effects of exercise training in a model of chronic allergic lung inflammation

AimsExercise training increases circulating and tissue levels of angiotensin-(1-7) [Ang-(1-7)], which was shown to attenuate inflammation and fibrosis in different diseases. Here, we evaluated whether Ang-(1-7)/Mas receptor is involved in the beneficial effects of aerobic training in a chronic model of asthma. Material and methodsBALB/c mice were subjected to a protocol of asthma induced by ovalbumin sensitization (OVA; 4 i.p. injections) and OVA challenge (3 times/week for 4 weeks). Simultaneously to the challenge period, part of the animals was continuously treated with Mas receptor antagonist (A779, 1 μg/h; for 28 days) and trained in a treadmill (TRE; 60% of the maximal capacity, 1 h/day, 5 days/week during 4 weeks). PGC1-α mRNA expression (qRT-PCR), plasma IgE and lung cytokines (ELISA), inflammatory cells infiltration (enzymatic activity assay) and airway remodeling (by histology) were evaluated. Key findingsBlocking the Mas receptor with A779 increased IgE and IL-13 levels and prevented the reduction in extracellular matrix deposition in airways in OVA-TRE mice. Mas receptor blockade prevented the reduction of myeloperoxidase activity, as well as, prevented exercise-induced IL-10 increase. These data show that activation of Ang-(1-7)/Mas receptor pathway is involved in the anti-inflammatory and anti-fibrotic effects of aerobic training in an experimental model of chronic asthma. SignificanceOur results support exercise training as a non-pharmacological tool to defeat lung remodeling induced by chronic pulmonary inflammation. Further, our result also supports development of new therapy based on Ang-(1-7) or Mas agonists as important tool for asthma treatment in those patients that cannot perform aerobic training.

GSK-3 Inhibition Modulates Metalloproteases in a Model of Lung Inflammation and Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is mainly characterized by aberrant extracellular matrix deposition, consequent to epithelial lung injury and myofibroblast activation, and inflammatory response. Glycogen synthase kinase 3 (GSK-3) is a serine–threonine kinase involved in several pathways, and its inhibition has been already suggested as a therapeutic strategy for IPF patients. There is evidence that GSK-3 is able to induce matrix metalloproteinase (MMP) expression and that its inhibition modulates MMP expression in the tissues. The aim of our study was to investigate the role of GSK-3 and its inhibition in the modulation of MMP-9 and -2 in an in vivo mouse model of lung fibrosis and in vitro using different cell lines exposed to pro-inflammatory or pro-fibrotic stimuli. We found that GSK-3 inhibition down-modulates gene expression and protein levels of MMP-9, MMP-2, and their inhibitors TIMP-1 and TIMP-2 in inflammatory cells harvested from bronchoalveolar lavage fluid (BALF) of mice treated with bleomycin as well as in interstitial alveolar macrophages and cuboidalized epithelial alveolar cells. To the same extent, GSK-3 inhibition blunted the increased MMP-9 and MMP-2 activity induced by pro-fibrotic stimuli in a human lung fibroblast cell line. Moreover, the αSMA protein level, a marker of fibroblast-to-myofibroblast transition involved in fibrosis, was decreased in primary fibroblasts treated with TGFβ following GSK-3 inhibition. Our results confirm the implication of GSK-3 in lung inflammation and fibrosis, suggesting that it might play its role by modulating MMP expression and activity but also pushing fibroblasts toward a myofibroblast phenotype and therefore enhancing extracellular matrix deposition. Thus, its inhibition could represent a possible therapeutic strategy.

Selective Imaging of Lung Macrophages Using [11C]PBR28-Based Positron Emission Tomography.

We tested whether the translocator protein (TSPO)-targeted positron emission tomography (PET) tracer, N-acetyl-N-(2-[11C]methoxybenzyl)-2-phenoxy-5-pyridinamine ([11C]PBR28), could distinguish macrophage dominant from neutrophilic inflammation better than 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) in mouse models of lung inflammation and assessed TSPO association with macrophages in lung tissue from the mouse models and in patients with chronic obstructive pulmonary disease (COPD). MicroPET imaging quantified [11C]PBR28 and [18F]FDG lung uptake in wild-type (Wt) C57BL/6J or heterozygous transgenic monocyte-deficient Wt/opT mice at 49 days after Sendai virus (SeV) infection, during macrophage-dominant inflammation, and in Wt mice at 3 days after SeV infection or 24 h after endotoxin instillation during neutrophilic inflammation. Immunohistochemical staining for TSPO in macrophages and neutrophils was performed using Mac3 and Ly6G for cell identification in mouse lung sections and CD68 and neutrophil elastase (NE) in human lung sections taken from explanted lungs from patients with COPD undergoing lung transplantation and donor lungs rejected for transplantation. Differences in tracer uptake among SeV-infected, endotoxin-treated, and uninfected/untreated control mice and in TSPO staining between neutrophils and macrophage populations in human lung sections were tested using analysis of variance. In Wt mice, [11C]PBR28 uptake (% injected dose/ml lung tissue) increased significantly with macrophage-dominant inflammation at 49 days (D49) after SeV infection compared to controls (p = <0.001) but not at 3 days (D49) after SeV infection (p = 0.167). [11C]PBR28 uptake was unchanged at 24 h after endotoxin instillation (p = 0.958). [18F]FDG uptake increased to a similar degree in D3 and D49 SeV-infected and endotoxin-treated Wt mice compared to controls with no significant difference in the degree of increase among the tested conditions. [11C]PBR28 but not [18F]FDG lung uptake at D49 post-SeV infection was attenuated in Wt/opT mice compared to Wt mice. TSPO localized predominantly to macrophages in mouse lung tissue by immunostaining, and TSPO staining intensity was significantly higher in CD68+ cells compared to neutrophils in the human lung sections. PET imaging with [11C]PBR28 can specifically detect macrophages versus neutrophils during lung inflammation and may be a useful biomarker of macrophage accumulation in lung disease.

Inorganic polyphosphate from the immunobiotic Lactobacillus rhamnosus CRL1505 prevents inflammatory response in the respiratory tract.

Lactobacillus (L.) rhamnosus CRL1505 accumulates inorganic polyphosphate (polyP) in its cytoplasm in response to environmental stress. The aim of this study was to evaluate the potential effects of polyP from the immunobiotic CRL1505 on an acute respiratory inflammation murine animal model induced by lipopolysaccharide (LPS).First, the presence of polyP granules in the cytoplasm of CRL1505 strain was evidenced by specific staining. Then, it was demonstrated in the intracellular extracts (ICE) of CRL1505 that polyP chain length is greater than 45 phosphate residues. In addition, the functionality of the genes involved in the polyP metabolism (ppk, ppx1 and ppx2) was corroborated by RT-PCR. Finally, the possible effect of the ICE of CRL1505 strain containing polyP and a synthetic polyP was evaluated in vivo using a murine model of acute lung inflammation. It was observed that the level of cytokines pro-inflammatory (IL-17, IL-6, IL-2, IL-4, INF-γ) in serum was normalized in mice treated with ICE, which would indicate that polyP prevents the local inflammatory response in the respiratory tract. The potential application of ICE from L. rhamnosus CRL1505 as a novel bioproduct for the treatment of respiratory diseases is one of the projections of this work.

Depletion of CD56+CD3+ invariant natural killer T cells prevents allergen-induced inflammation in humanized mice

CD56-expressing natural killer (NK) cells as well as invariant NK T (iNKT) cells have been shown to either promote or inhibit allergic immune responses. The aim of the present study was to investigate the impact of these cells in a recently developed humanized mouse model of allergen-induced IgE-dependent gut and lung inflammation. Nonobese diabetic-severe combined immunodeficiency γ-chain knockout mice were injected intraperitoneally with human PBMCs or CD56-depleted (CD56neg) PBMCs from highly sensitized donors with birch or grass pollen allergy together with the respective allergen or with NaCl as a control. Three weeks later, the mice were challenged with the allergen rectally and gut inflammation was monitored by video miniendoscopy and by histology. Furthermore, airway inflammation was measured after an additional intranasal allergen challenge. Allergen-specific human IgE in mouse sera, detectable only after coinjection of the respective allergen, was reduced in mice being injected with CD56neg PBMCs compared with in mice receiving nondepleted PBMCs. Consequently, allergen-induced IgE-dependent colitis, airway hyperreactivity, and mucus-producing goblet cells were significantly inhibited in these mice. Interestingly, reconstitution of CD56neg PBMCs with nondepleted CD56+ cells and with CD56+CD3+ iNKT cells restored gut as well as lung inflammation, whereas addition of CD3-depleted CD56+ cells did not. These results demonstrate that allergen-specific gut and lung inflammation in PBMC-engrafted humanized mice is promoted by CD56+CD3+ iNKT cells, which opens new possibilities of therapeutic intervention in allergic diseases.

Mesenchymal stromal cells reprogram macrophages with processing bodies

Background & Aim: Mesenchymal stromal cells (MSCs) are an investigational cell therapy for inflammatory diseases. Although they have robust anti-inflammatory properties, their success has been variable in clinical trials due to an unclear understanding of their mechanism. Once injected, a majority of MSCs traffic to the lung, where they are rapidly cleared, signifying an opportunity to target lung inflammatory [Figure presented] conditions such as acute respiratory distress syndrome (ARDS). ARDS is a catastrophic condition of the lungs, involving pulmonary inflammation that develops with severe SARS-CoV2 and other respiratory infections. MSCs are expected to prevent alveolar damage by suppressing the immune response and there is evidence that MSCs protect in phase I/IIa trials for ARDS associated with COVID-19. While these results are promising, understanding the mechanism is critical to determine dosing, maximize efficacy, and ultimately lead to an approved product. Methods, Results & Conclusion: We and others have demonstrated that within their short time in the lung, MSCs interact with monocytes and macrophages. Through direct cell contact, MSCs transfer cytoplasmic components, notably cytoplasmic processing-bodies (p-bodies) to monocytes and macrophages. P-bodies are membrane-less organelles that contain RNA binding proteins, microRNAs, and mRNAs enriched for genes that regulate the transcriptional landscape of cells. MSC interactions result in long-term transcriptional reprogramming of monocytes and macrophages to suppress a helper T cell response and upregulate tissue repair pathways. To investigate the mechanisms of MSCs in vivo, we utilized 2 mouse models of lung inflammation: 1. intranasal lipopolysaccharide (LPS) to study general acute inflammation and 2. an engineered vesicular stomatitis virus (VSV) with a SARS-CoV2 Spike protein. Using these models, we demonstrated that during inflammation cytoplasm of MSCs transferred to lung macrophages to decrease activation and the expression of MHC-II. Further, MSCs prevented a decrease in resident alveolar macrophages, suppressed proinflammatory macrophages, and blocked an influx in infiltrating monocytes (Fig 1). Depleting p-bodies from MSCs abolished the beneficial effects, despite transfer cytoplasmic component to macrophages at similar levels of control MSCs. Overall, our data suggest a novel form of cell communication that could explain how MSCs could lead to long-term beneficial effects on lung inflammation despite being rapidly cleared. [Figure presented]

Comparison of plasma and pulmonary availability of chlorogenic acid, forsythiaside A and baicalin after intratracheal and intravenous administration of Shuang-Huang-Lian injection

Ethnopharmacological relevanceThe off-label nebulization of Shuang-Huang-Lian (SHL) injection is often utilized to treat respiratory tract infections in China. However, the pulmonary biopharmaceutics of SHL was generally unknown, limiting the rational selection of therapeutic dose and dose frequency. Aim of the studyTo characterize the size distribution of nebulized aerosols and to compare the pharmacokinetics and the lung distribution of three chemical makers of SHL, chlorogenic acid (CHA), forsythiaside A (FTA) and baicalin (BC), after intratracheal and intravenous administration of SHL to rats. Materials and methodsThe droplet size distribution profiles over nebulization process were dynamically monitored using a laser diffraction method whereas the levels of CHA, FTA and BC in plasma, lung tissues and bronchoalveolar lavage fluids (BALF) were determined by a validated LC-MS/MS assay. The pulmonary anti-inflammatory efficacy was evaluated using a lipopolysaccharide (LPS) induced lung inflammation model as indicated by the level of tumor necrosis factor-α (TNF-α) in BALF. ResultsThe nebulization of SHL showed good inhalability and allowed the aerosols to reach the upper or lower respiratory tract dependent on the performance of selected nebulizers. Following intratracheal administration of SHL at different doses, CHA, FTA and BC were absorbed into the bloodstream with the mean absorption time being 67.5, 63.5 and 114 min, respectively, rendering mean absolute bioavailabilities between 42.4% and 61.4% roughly independent of delivered dose. Relative to the intravenous injection, the intrapulmonary delivery increased the lung-to-plasma concentration ratios of CHA, FTA and BC by more than 100 folds and markedly improved the lung availability by 563–676 folds, leading to enhanced and prolonged lung retention. The production of TNF-α in BALF was decreased by ~50% at an intratracheal dose of 125 μL/kg SHL to LPS-treated mice. ConclusionThe nebulization delivery of SHL is a promising alternative to the intravenous injection for the treatment of respiratory tract infections.

2-Methoxyestradiol Protects Against Lung Ischemia/Reperfusion Injury by Upregulating Annexin A1 Protein Expression.

Background: 2-Methoxyestradiol (2ME), a natural 17-β estradiol metabolite, is a potent anti-inflammatory agent, but its effect on ischemia/reperfusion (IR)-induced acute lung inflammation remains unknown. Annexin A1 (AnxA1), a glucocorticoid-regulated protein, is effective at inhibiting neutrophil transendothelial migration by binding the formyl peptide receptors (FPRs). We aimed to investigate whether 2ME upregulates the expression of AnxA1 and protects against IR-induced lung damage.Methods: IR-mediated acute lung inflammation was induced by ischemia for 40 min followed by reperfusion for 60 min in an isolated, perfused rat lung model. The rat lungs were randomly treated with vehicle or 2ME, and the functional relevance of AnxA1 was determined using an anti-AnxA1 antibody or BOC2 (a pan-receptor antagonist of the FPR). In vitro, human primary alveolar epithelial cells (HPAECs) and rat neutrophils were pretreated with 2ME and an AnxA1 siRNA or anti-AnxA1 antibody and subjected to hypoxia-reoxygenation (HR).Results: 2ME significantly decreased all lung edema parameters, neutrophil infiltration, oxidative stress, proinflammatory cytokine production, lung cell apoptosis, tight junction protein disruption, and lung tissue injury in the IR-induced acute lung inflammation model. 2ME also increased the expression of the AnxA1 mRNA and protein and suppressed the activation of nuclear factor-κB (NF-κB). In vitro, 2ME attenuated HR-triggered NF-κB activation and interleukin-8 production in HPAECs, decreased transendothelial migration, tumor necrosis factor-α production, and increased apoptosis in neutrophils exposed to HR. These protective effects of 2ME were significantly abrogated by BOC2, the anti-AnxA1 antibody, or AnxA1 siRNA.Conclusions: 2ME ameliorates IR-induced acute lung inflammation by increasing AnxA1 expression. Based on these results, 2ME may be a promising agent for attenuating IR-induced lung injury.

Airways glutathione S-transferase omega-1 and its A140D polymorphism are associated with severity of inflammation and respiratory dysfunction in cystic fibrosis

BackgroundGlutathione S-transferase omega-1 (GSTO1-1) is a cytosolic enzyme that modulates the S-thiolation status of intracellular factors involved in cancer cell survival or in the inflammatory response. Studies focusing on chronic obstructive pulmonary disease (COPD) have demonstrated that GSTO1-1 is detectable in alveolar macrophages, airway epithelium and in the extracellular compartment, where its functions have not been completely understood. Moreover GSTO1-1 polymorphisms have been associated with an increased risk to develop COPD. Against this background, the aim of this study was to evaluate GSTO1-1 levels and its polymorphisms in cystic fibrosis (CF) patients. MethodsClinical samples from a previous study published by our groups were analyzed for GSTO1-1 levels and polymorphisms. For comparison, a model of lung inflammation in CFTR-knock out mice was also used. ResultsOur data document that soluble GSTO1-1 can be found in the airways of CF patients and correlates with inflammatory parameters such as neutrophilic elastase and the chemokine IL-8. A negative correlation was found between GSTO1-1 levels and the spirometric parameter FEV1 and the FEV1/FVC ratio. Additionally, the A140D polymorphism of GSTO1-1 was associated with lower levels of the antiinflammatory mediators PGE2 and 15(S)-HETE, and with lower values of the FEV1/FVC ratio in CF subjects with the homozygous CFTR ΔF508 mutation. ConclusionsOur data suggest that extracellular GSTO1-1 and its polymorphysms could have a biological and clinical significance in CF. Pathophysiological functions of GSTOs are far from being completely understood, and more studies are required to understand the role(s) of extracellular GSTO1-1 in inflamed tissues.

IL36 is a critical upstream amplifier of neutrophilic lung inflammation in mice

IL-36, which belongs to the IL-1 superfamily, is increasingly linked to neutrophilic inflammation. Here, we combined in vivo and in vitro approaches using primary mouse and human cells, as well as, acute and chronic mouse models of lung inflammation to provide mechanistic insight into the intercellular signaling pathways and mechanisms through which IL-36 promotes lung inflammation. IL-36 receptor deficient mice exposed to cigarette smoke or cigarette smoke and H1N1 influenza virus had attenuated lung inflammation compared with wild-type controls. We identified neutrophils as a source of IL-36 and show that IL-36 is a key upstream amplifier of lung inflammation by promoting activation of neutrophils, macrophages and fibroblasts through cooperation with GM-CSF and the viral mimic poly(I:C). Our data implicate IL-36, independent of other IL-1 family members, as a key upstream amplifier of neutrophilic lung inflammation, providing a rationale for targeting IL-36 to improve treatment of a variety of neutrophilic lung diseases.

The mechanism and active compounds of semen armeniacae amarum treating coronavirus disease 2019 based on network pharmacology and molecular docking.

BackgroundCoronavirus disease 2019 (COVID-19) outbreak is progressing rapidly, and poses significant threats to public health. A number of clinical practice results showed that traditional Chinese medicine (TCM) plays a significant role for COVID-19 treatment.ObjectiveTo explore the active components and molecular mechanism of semen armeniacae amarum treating COVID-19 by network pharmacology and molecular docking technology.MethodsThe active components and potential targets of semen armeniacae amarum were retrieved from traditional Chinese medicine systems pharmacology (TCMSP) database. Coronavirus disease 2019-associated targets were collected in the GeneCards, TTD, OMIM and PubChem database. Compound target, compound-target pathway and medicine-ingredient-target disease networks were constructed by Cytoscape 3.8.0. Protein-protein interaction (PPI) networks were drawn using the STRING database and Cytoscape 3.8.0 software. David database was used for gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. The main active components were verified by AutoDock Vina 1.1.2 software. A lipopolysaccharide (LPS)-induced lung inflammation model in Institute of Cancer Research (ICR) mice was constructed and treated with amygdalin to confirm effects of amygdalin on lung inflammation and its underlying mechanisms by western blot analyses and immunofluorescence.ResultsThe network analysis revealed that nine key, active components regulated eight targets (Proto-oncogene tyrosine-protein kinase SRC (SRC), interleukin 6 (IL6), mitogen-activated protein kinase 1 (MAPK1), mitogen-activated protein kinase 3 (MAPK3), vascular endothelial growth factor A (VEGFA), epidermal growth factor receptor (EGFR), HRAS proto-oncogene (HRAS), caspase-3 (CASP3)). Gene ontology and KEGG enrichment analysis suggested that semen armeniacae amarum plays a role in COVID-19 by modulating 94 biological processes, 13 molecular functions, 15 cellular components and 80 potential pathways. Molecular docking indicated that amygdalin had better binding activity to key targets such as IL6, SRC, MAPK3, SARS coronavirus-2 3C-like protease (SARS-CoV-2 3CLpro) and SARS-CoV-2 angiotensin converting enzyme II (ACE2). Experimental validation revealed that the lung pathological injury and inflammatory injury were significantly increased in the model group and were improved in the amygdalin group.ConclusionAmygdalin is a candidate compound for COVID-19 treatment by regulating IL6, SRC, MAPK1 EGFR and VEGFA to involve in PI3K-Akt signalling pathway, VEGF signalling pathway and MAPK signalling pathway. Meanwhile, amygdalin has a strong affinity for SARS-CoV-2 3CLpro and SARS-CoV-2 ACE2 and therefore prevents the virus transcription and dissemination.

Group 2 Innate Lymphoid Cells: Team Players in Regulating Asthma.

Type 2 immunity helps protect the host from infection, but it also plays key roles in tissue homeostasis, metabolism, and repair. Unfortunately, inappropriate type 2 immune reactions may lead to allergy and asthma. Group 2 innate lymphoid cells (ILC2s) in the lungs respond rapidly to local environmental cues, such as the release of epithelium-derived type 2 initiator cytokines/alarmins, producing type 2 effector cytokines such as IL-4, IL-5, and IL-13 in response to tissue damage and infection. ILC2s are associated with the severity of allergic asthma, and experimental models of lung inflammation have shown how they act as playmakers, receiving signals variously from stromal and immune cells as well as the nervous system and then distributing cytokine cues to elicit type 2 immune effector functions and potentiate CD4+ T helper cell activation, both of which characterize the pathology of allergic asthma. Recent breakthroughs identifying stromal- and neuronal-derived microenvironmental cues that regulate ILC2s, along with studies recognizing the potential plasticity of ILC2s, have improved our understanding of the immunoregulation of asthma and opened new avenues for drug discovery.