scholarly journals Ginsenoside Rg1 Regulates SIRT1 to Ameliorate Sepsis-Induced Lung Inflammation and Injury via Inhibiting Endoplasmic Reticulum Stress and Inflammation

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
Qian-Lu Wang ◽  
Lei Yang ◽  
Yue Peng ◽  
Min Gao ◽  
Ming-Shi Yang ◽  
...  
Keyword(s):  
Lung Injury ◽  
Er Stress ◽  
Inflammatory Cytokines ◽  
Lung Inflammation ◽  
A549 Cells ◽  
Mouse Lung ◽  
Ginsenoside Rg1 ◽  
Marker Proteins

Objectives. To investigate the protective effect of ginsenoside Rg1 on relieving sepsis-induced lung inflammation and injury in vivo and in vitro. Methods. Cultured human pulmonary epithelial cell line A549 was challenged with LPS to induce cell injury, and CLP mouse model was generated to mimic clinical condition of systemic sepsis. Rg1 was applied to cells or animals at indicated dosage. Apoptosis of cultured cells was quantified by flow cytometry, along with ELISA for inflammatory cytokines in supernatant. For septic mice, lung tissue pathology was examined, plus ELISA assay for serum cytokines. Western blotting was used to examine the activation of inflammatory pathways and ER stress marker proteins in both cells and mouse lung tissues. Reactive oxygen species (ROS) level was quantified by DCFDA kit. Results. Ginsenoside Rg1 treatment remarkably suppressed apoptosis rate of LPS-induced A549 cells, relieved mouse lung tissue damage, and elevated survival rate. Rg1 treatment also rescued cells from LPS-induced intracellular ROS. In both A549 cells and mouse lung tissues, further study showed that Rg1 perfusion significantly suppressed the secretion of inflammatory cytokines including tumor necrosis factor- (TNF-) alpha and interleukin- (IL-) 6 and relieved cells from ER stress as supported by decreased expression of marker proteins via upregulating sirtuin 1 (SIRT1). Conclusion. Our results showed that ginsenoside Rg1 treatment effectively relieved sepsis-induced lung injury in vitro and in vivo, mainly via upregulating SIRT1 to relieve ER stress and inflammation. These findings provide new insights for unrevealing potential candidate for severe sepsis accompanied with lung injury.

scholarly journals The Crucial Role of PPARγ-Egr-1-Pro-Inflammatory Mediators Axis in IgG Immune Complex-Induced Acute Lung Injury

2021 ◽  
Vol 12 ◽  
Author(s):  
Chunguang Yan ◽  
Jing Chen ◽  
Yue Ding ◽  
Zetian Zhou ◽  
Bingyu Li ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Immune Complex ◽  
Inflammatory Mediators ◽  
Lung Inflammation ◽  
Acute Lung Inflammation ◽  
Pparγ Agonist

BackgroundThe ligand-activated transcription factor peroxisome proliferator-activated receptor (PPAR) γ plays crucial roles in diverse biological processes including cellular metabolism, differentiation, development, and immune response. However, during IgG immune complex (IgG-IC)-induced acute lung inflammation, its expression and function in the pulmonary tissue remains unknown.ObjectivesThe study is designed to determine the effect of PPARγ on IgG-IC-triggered acute lung inflammation, and the underlying mechanisms, which might provide theoretical basis for therapy of acute lung inflammation.SettingDepartment of Pathogenic Biology and Immunology, Medical School of Southeast UniversitySubjectsMice with down-regulated/up-regulated PPARγ activity or down-regulation of Early growth response protein 1 (Egr-1) expression, and the corresponding controls.InterventionsAcute lung inflammation is induced in the mice by airway deposition of IgG-IC. Activation of PPARγ is achieved by using its agonist Rosiglitazone or adenoviral vectors that could mediate overexpression of PPARγ. PPARγ activity is suppressed by application of its antagonist GW9662 or shRNA. Egr-1 expression is down-regulated by using the gene specific shRNA.Measures and Main ResultsWe find that during IgG-IC-induced acute lung inflammation, PPARγ expression at both RNA and protein levels is repressed, which is consistent with the results obtained from macrophages treated with IgG-IC. Furthermore, both in vivo and in vitro data show that PPARγ activation reduces IgG-IC-mediated pro-inflammatory mediators’ production, thereby alleviating lung injury. In terms of mechanism, we observe that the generation of Egr-1 elicited by IgG-IC is inhibited by PPARγ. As an important transcription factor, Egr-1 transcription is substantially increased by IgG-IC in both in vivo and in vitro studies, leading to augmented protein expression, thus amplifying IgG-IC-triggered expressions of inflammatory factors via association with their promoters.ConclusionDuring IgG-IC-stimulated acute lung inflammation, PPARγ activation can relieve the inflammatory response by suppressing the expression of its downstream target Egr-1 that directly binds to the promoter regions of several inflammation-associated genes. Therefore, regulation of PPARγ-Egr-1-pro-inflammatory mediators axis by PPARγ agonist Rosiglitazone may represent a novel strategy for blockade of acute lung injury.

Ulinastatin Activated The ERK5/Mer Signaling Pathway To Promote Macrophage Efferocytosis And Ameliorate Lung Inflammation

2021 ◽  
Author(s):  
Jinju Li ◽  
Rongge Shao ◽  
Qiuwen Xie ◽  
XueKe Du
Keyword(s):  
Lung Injury ◽  
Signaling Pathway ◽  
Lung Inflammation ◽  
Raw264.7 Cells ◽  
Inflammatory Factors ◽  
Inflammatory Factor ◽  
Dependent Manner ◽  
Anti Inflammatory

Abstract Purpose:Ulinastatin (UTI) is an endogenous protease inhibitor with potent anti-inflammatory, antioxidant and organ protective effects. The inhibitor has been reported to ameliorate inflammatory lung injury but precise mechanisms remain unclear. Methods: An in vivo model of lung injury has been constructed by intratracheal infusion of lipopolysaccharide (LPS). The number of neutrophils and the phagocytosis of apoptotic neutrophils were observed by Diff- Quick method. Lung injury was observed by HE staining .BALF cells were counted by hemocytometer and concentrations of protein plus inflammatory factors were measured with a BCA test kit. During in vitro experiments, RAW264.7 cells were pretreated with UTI (1000 and 5000U/ mL), stained with CellTrackerTM Green B0DIPYTM and HL60 cells added with UV-induced apoptosis and PKH26 Red staining. The expression of ERK5\Mer related proteins was detected by western blot and immunofluorescence.Results: An in vivo model of lung injury has been constructed by intratracheal infusion of lipopolysaccharide (LPS). UTI treatment enhanced the phagocytotic effect of mouse alveolar macrophages on neutrophils, alleviated lung lesions, decreased the pro-inflammatory factor and total protein content of BALF and increased levels of anti-inflammatory factors. in vitro experiments ，UTI enhanced the phagocytosis of apoptotic bodies by RAW264.7 cells in a dose-dependent manner. Increased expression levels of ERK5 and Mer by UTI were shown by Western blotting and immunofluorescence.Conclusions: UTI mediated the activation of the ERK5/Mer signaling pathway, enhanced phagocytosis of neutrophils by macrophages and improved lung inflammation. The current study indicates potential new clinical approaches for accelerating the recovery from lung inflammation.

scholarly journals Role of LecA and LecB Lectins in Pseudomonas aeruginosa-Induced Lung Injury and Effect of Carbohydrate Ligands

2009 ◽  
Vol 77 (5) ◽  
pp. 2065-2075 ◽  
Author(s):  
Chanez Chemani ◽  
Anne Imberty ◽  
Sophie de Bentzmann ◽  
Maud Pierre ◽  
Michaela Wimmerová ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Parental Strain ◽  
A549 Cells ◽  
Carbohydrate Ligands ◽  
Vitro Model

ABSTRACT Pseudomonas aeruginosa is a frequently encountered pathogen that is involved in acute and chronic lung infections. Lectin-mediated bacterium-cell recognition and adhesion are critical steps in initiating P. aeruginosa pathogenesis. This study was designed to evaluate the contributions of LecA and LecB to the pathogenesis of P. aeruginosa-mediated acute lung injury. Using an in vitro model with A549 cells and an experimental in vivo murine model of acute lung injury, we compared the parental strain to lecA and lecB mutants. The effects of both LecA- and Lec B-specific lectin-inhibiting carbohydrates (α-methyl-galactoside and α-methyl-fucoside, respectively) were evaluated. In vitro, the parental strain was associated with increased cytotoxicity and adhesion on A549 cells compared to the lecA and lecB mutants. In vivo, the P. aeruginosa-induced increase in alveolar barrier permeability was reduced with both mutants. The bacterial burden and dissemination were decreased for both mutants compared with the parental strain. Coadministration of specific lectin inhibitors markedly reduced lung injury and mortality. Our results demonstrate that there is a relationship between lectins and the pathogenicity of P. aeruginosa. Inhibition of the lectins by specific carbohydrates may provide new therapeutic perspectives.

scholarly journals PKR-dependent CHOP induction limits hyperoxia-induced lung injury

2011 ◽  
Vol 300 (3) ◽  
pp. L422-L429 ◽  
Author(s):  
Tricia I. Lozon ◽  
Alison J. Eastman ◽  
Gustavo Matute-Bello ◽  
Peter Chen ◽  
Teal S. Hallstrand ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lung Injury ◽  
Er Stress ◽  
Initiation Factor ◽  
Mouse Lung ◽  
Epithelial Cell Line ◽  
Lung Edema ◽  
Α Subunit ◽  
Chop Expression

Supplemental O2is commonly employed in patients with respiratory failure; however, hyperoxia is also a potential contributor to lung injury. In animal models, hyperoxia causes oxidative stress in the lungs, resulting in increased inflammation, edema, and permeability. We hypothesized that oxidative stress from prolonged hyperoxia leads to endoplasmic reticulum (ER) stress, resulting in activation of the unfolded protein response (UPR) and induction of CCAAT enhancer-binding protein homologous protein (CHOP), a transcription factor associated with cell death in the setting of persistent ER stress. To test this hypothesis, we exposed the mouse lung epithelial cell line MLE-12 to 95% O2for 8–24 h and evaluated for evidence of UPR induction and CHOP induction. Hyperoxia caused increased CHOP expression without other evidence of UPR activation. Because CHOP expression is preceded by phosphorylation of the α-subunit of the eukaryotic initiation factor-2 (eIF2α), we evaluated the role of double-stranded RNA-activated protein kinase (PKR), a non-UPR-associated eIF2α kinase. Hyperoxia caused PKR phosphorylation, and RNA interference knockdown of PKR attenuated hyperoxia-induced CHOP expression. In vivo, hyperoxia induced PKR phosphorylation and CHOP expression in the lungs without other biochemical evidence for ER stress. Additionally, Ddit3−/−(CHOP-null) mice had increased lung edema and permeability, indicating a previously unknown protective role for CHOP after prolonged hyperoxia. We conclude that hyperoxia increases CHOP expression via an ER stress-independent, PKR-dependent pathway and that increased CHOP expression protects against hyperoxia-induced lung injury.

Supernatant of stored platelets causes lung inflammation and coagulopathy in a novel in vivo transfusion model

Blood ◽  
2010 ◽  
Vol 116 (8) ◽  
pp. 1360-1368 ◽  
Author(s):  
Alexander P. J. Vlaar ◽  
Jorrit J. Hofstra ◽  
Wim Kulik ◽  
Henk van Lenthe ◽  
Rienk Nieuwland ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Lung Inflammation ◽  
Pulmonary Injury ◽  
Blood Products ◽  
Platelet Concentrates ◽  
Priming Activity ◽  
Neutrophil Priming

Abstract Transfusion-related acute lung injury is suggested to be a “2-hit” event resulting from priming and activation of pulmonary neutrophils. Activation may result from infusion of lysophosphatidylcholines (LysoPCs), which accumulate during storage of blood products. In the present study, we developed a syngeneic in vivo transfusion model to test whether storage of platelet concentrates (PLTs) results in lung injury in healthy rats as well as in a “2-hit” model using lipopolysaccharide-pretreated rats. In addition, the effect of washing of platelets was studied. In healthy rats, transfusion of aged PLTs caused mild lung inflammation. In LPS-pretreated rats, transfusion of aged PLTs, but not fresh PLTs, augmented pulmonary systemic coagulopathy. When PLTs components were transfused separately, supernatant of aged PLTs, but not washed aged platelets, induced pulmonary injury in the “2-hit” model. Supernatants of aged PLTs contained increased concentrations of LysoPCs compared with fresh PLTs, which enhanced neutrophil priming activity in vitro. We conclude that transfusion of aged PLTs induces lung inflammation in healthy rats. In a “2-hit” model, aged PLTs contribute to pulmonary and systemic coagulopathy, which may be mediated by LysoPCs, which accumulate in the supernatant of PLTs during storage.

scholarly journals A Subanesthetic Dose of Isoflurane during Postconditioning Ameliorates Zymosan-Induced Neutrophil Inflammation Lung Injury and Mortality in Mice

2013 ◽  
Vol 2013 ◽  
pp. 1-14 ◽  
Author(s):  
Hui Wang ◽  
Jing Fan ◽  
Nan-lin Li ◽  
Jun-tang Li ◽  
Shi-fang Yuan ◽  
...  
Keyword(s):  
Lung Injury ◽  
Nuclear Translocation ◽  
Inflammatory Responses ◽  
Weight Ratio ◽  
Polymorphonuclear Neutrophils ◽  
Mouse Lung ◽  
Endothelial Adhesion Molecule ◽  
Primary Mouse

Anesthetic isoflurane (ISO) has immunomodulatory effects. In the present study, we investigated whether a subanesthetic dose of ISO (0.7%) protected against zymosan (ZY) induced inflammatory responses in the murine lung and isolated neutrophils. At 1 and 6 hrs after ZY administration intraperitoneally, ISO was inhaled for 1 hr, and 24 hrs later, lung inflammation and injury were assessed. We found that ISO improved the survival rate of mice and mitigated lung injury as characterized by the histopathology, wet-to-dry weight ratio, protein leakage, and lung function index. ISO significantly attenuated ZY-induced lung neutrophil recruitment and inflammation. This was suggested by the downregulation of (a) endothelial adhesion molecule expression and myeloperoxidase (MPO) activity in lung tissue and polymorphonuclear neutrophils (b) chemokines, and (c) proinflammatory cytokines in BALF. Furthermore, ZY-induced nuclear translocation and DNA-binding activity of NF-κB p65 were also reduced by ISO. ISO treatment inhibited iNOS expression and activity, as well as subsequent nitric oxide generation. Consistent with thesein vivoobservations,in vitrostudies confirmed that ISO blocked NF-κB and iNOS activation in primary mouse neutrophils challenged by ZY. These results provide evidence that 0.7% ISO ameliorates inflammatory responses in ZY-treated mouse lung and primary neutrophils.

scholarly journals Nur77 attenuates endothelin-1 expression via downregulation of NF-κB and p38 MAPK in A549 cells and in an ARDS rat model

2016 ◽  
Vol 311 (6) ◽  
pp. L1023-L1035 ◽  
Author(s):  
Yujie Jiang ◽  
Yi Zeng ◽  
Xia Huang ◽  
Yueqiu Qin ◽  
Weigui Luo ◽  
...  
Keyword(s):  
Lung Injury ◽  
P38 Mapk ◽  
Rat Model ◽  
Nuclear Export ◽  
Nuclear Translocation ◽  
A549 Cells ◽  
Orphan Receptor ◽  
Endothelin 1

Acute respiratory distress syndrome (ARDS) is characterized by inflammatory injury to the alveolar and capillary barriers that results in impaired gas exchange and severe acute respiratory failure. Nuclear orphan receptor Nur77 has emerged as a regulator of gene expression in inflammation, and its role in the pathogenesis of ARDS is not clear. The objective of this study is to investigate the potential role of Nur77 and its underlying mechanism in the regulation of endothelin-1 (ET-1) expression in lipopolysaccharide (LPS)-induced A549 cells and an ARDS rat model. We demonstrate that LPS induced Nur77 expression and nuclear export in A549 cells. Overexpression of Nur77 markedly decreased basal and LPS-induced ET-1 expression in A549 cells, whereas knockdown of Nur77 increased the ET-1 expression. LPS-induced phosphorylation and nuclear translocation of NF-κB and p38 MAPK were blocked by Nur77 overexpression and augmented by Nur77 knockdown in A549 cells. In vivo, LPS induced Nur77 expression in lung in ARDS rats. Pharmacological activation of Nur77 by cytosporone B (CsnB) inhibited ET-1 expression in ARDS rats, decreased LPS-induced phosphorylation of NF-κB and p38 MAPK, and relieved lung, liver, and kidney injury. Pharmacological deactivation of Nur77 by 1,1-bis-(3′-indolyl)-1-(p-hydroxyphenyl)methane (DIM-C-pPhOH, C-DIM8) had no effect on ET-1 expression and lung injury. These results indicated that Nur77 decreases ET-1 expression by suppressing NF-κB and p38 MAPK in LPS-stimulated A549 cells in vitro, and, in an LPS-induced ARDS rat model, CsnB reduced ET-1 expression and lung injury in ARDS rats.

scholarly journals Diesel Exhaust Particulates Induce Neutrophilic Lung Inflammation by Modulating Endoplasmic Reticulum Stress-Mediated CXCL1/KC Expression in Alveolar Macrophages

Molecules ◽  
2020 ◽  
Vol 25 (24) ◽  
pp. 6046 ◽  
Author(s):  
Dong Im Kim ◽  
Mi-Kyung Song ◽  
Hye-In Kim ◽  
Kang Min Han ◽  
Kyuhong Lee
Keyword(s):  
Endoplasmic Reticulum ◽  
Er Stress ◽  
Alveolar Macrophages ◽  
Diesel Exhaust ◽  
Lung Inflammation ◽  
Binding Protein ◽  
In Vitro Study ◽  
Vitro Study

Diesel exhaust particulates (DEP) have adverse effects on the respiratory system. Endoplasmic reticulum (ER) abnormalities contribute to lung inflammation. However, the relationship between DEP exposure and ER stress in the respiratory immune system and especially the alveolar macrophages (AM) is poorly understood. Here, we examined ER stress and inflammatory responses using both in vivo and in vitro study. For in vivo study, mice were intratracheally instilled with 25, 50, and 100 μg DEP and in vitro AM were stimulated with DEP at 1, 2, and 3 mg/mL. DEP increased lung weight and the number of inflammatory cells, especially neutrophils, and inflammatory cytokines in bronchoalveolar lavage fluid of mice. DEP also increased the number of DEP-pigmented AM and ER stress markers including bound immunoglobulin protein (BiP) and CCAAT/enhancer binding protein-homologous protein (CHOP) were upregulated in the lungs of DEP-treated mice. In an in vitro study, DEP caused cell damage, increased intracellular reactive oxygen species, and upregulated inflammatory genes and ER stress-related BiP, CHOP, splicing X-box binding protein 1, and activating transcription factor 4 expressions in AM. Furthermore, DEP released the C-X-C Motif Chemokine Ligand 1 (CXCL1/KC) in AM. In conclusion, DEP may contribute to neutrophilic lung inflammation pathogenesis by modulating ER stress-mediated CXCL1/KC expression in AM.

Effects of autophagy on LPS-induced lung inflammation and acute lung injury (ALI) in vitro and in vivo

2018 ◽  
Author(s):  
Lian Liu ◽  
Dan Xu ◽  
Tao Wang ◽  
Zhicheng Yuan ◽  
Luqi Dai ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Lung Inflammation
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