scholarly journals BMSC-Derived Exosomes Ameliorate LPS-Induced Acute Lung Injury by miR-384-5p-Controlled Alveolar Macrophage Autophagy

2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Xuan Liu ◽  
Chengjin Gao ◽  
Yang Wang ◽  
Lei Niu ◽  
Shaowei Jiang ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Alveolar Macrophage ◽  
Vascular Permeability ◽  
Alveolar Macrophages ◽  
Weight Ratio ◽  
Beclin 1 ◽  
Cell Counting ◽  
Pulmonary Vascular Permeability ◽  
Therapeutic Mechanism

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are common critical diseases. Bone marrow mesenchymal stem cell (BMSC) transplantation is previously shown to effectively rescue injured lung tissues. The therapeutic mechanism of BMSC-derived exosomes is not fully understood. Here, we investigated the BMSC-derived exosomal microRNAs (miRNAs) on effecting lipopolysaccharide- (LPS-) induced ALI and its mechanism. In vitro, rat alveolar macrophages were treated with or without exosomes in the presence of 10 μg/ml LPS for 24 h. Cell viability was determined with Cell Counting Kit-8 assay. Apoptotic ratio was determined with TUNEL and Annexin V-FITC/PI double staining. The levels of miR-384-5p and autophagy-associated genes were measured by RT-qPCR and western blot. Autophagy was observed by TEM and assessed by means of the mRFP-GFP-LC3 adenovirus transfection assay. In vivo, we constructed LPS-induced ALI rat models. Exosomes were injected into rats via the caudal vein or trachea 4 h later after LPS treatment. The lung histological pathology was determined by H&E staining. Pulmonary vascular permeability was assessed by wet-to-dry weight ratio and Evans blue dye leakage assay, and inflammatory cytokines in serum and BALF were measured by ELISA. Furthermore, the therapeutic mechanism involved in miR-384-5p and Beclin-1 was determined. The results showed that BMSC-derived exosomes were taken up by the alveolar macrophages and attenuated LPS-induced alveolar macrophage viability loss and apoptosis. Exosomes effectively improved the survival rate of ALI rats within 7 days, which was associated with alleviating lung pathological changes and pulmonary vascular permeability and attenuating inflammatory response. Furthermore, this study for the first time found that miR-384-5p was enriched in BMSC-derived exosomes, and exosomal miR-384-5p resulted in relieving LPS-injured autophagy disorder in alveolar macrophages by targeting Beclin-1. Therefore, exosomal miR-384-5p could be demonstrated as a promising therapeutic strategy for ALI/ARDS.

scholarly journals Anti-Inflammatory Effects of Monoammonium Glycyrrhizinate on Lipopolysaccharide-Induced Acute Lung Injury in Mice through Regulating Nuclear Factor-Kappa B Signaling Pathway

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaoying Huang ◽  
Jiangfeng Tang ◽  
Hui Cai ◽  
Yi Pan ◽  
Yicheng He ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Signaling Pathway ◽  
Interleukin 1 ◽  
Intratracheal Instillation ◽  
Weight Ratio ◽  
Dry Weight ◽  
Inflammatory Cells ◽  
Lavage Fluid ◽  
Therapeutic Mechanism

The present study aimed to investigate the therapeutic effect of monoammonium glycyrrhizinate (MAG) on lipopolysaccharide- (LPS-) induced acute lung injury (ALI) in mice and possible mechanism. Acute lung injury was induced in BALB/c mice by intratracheal instillation of LPS, and MAG was injected intraperitoneally 1 h prior to LPS administration. After ALI, the histopathology of lungs, lung wet/dry weight ratio, protein concentration, and inflammatory cells in the bronchoalveolar lavage fluid (BALF) were determined. The levels of tumor necrosis factor-α(TNF-α) and interleukin-1β(IL-1β) in the BALF were measured by ELISA. The activation of NF-κB p65 and IκB-αof lung homogenate was detected by Western blot. Pretreatment with MAG attenuated lung histopathological damage induced by LPS and decreased lung wet/dry weight ratio and the concentrations of protein in BALF. At the same time, MAG reduced the number of inflammatory cells in lung and inhibited the production of TNF-αand IL-1βin BALF. Furthermore, we demonstrated that MAG suppressed activation of NF-κB signaling pathway induced by LPS in lung. The results suggested that the therapeutic mechanism of MAG on ALI may be attributed to the inhibition of NF-κB signaling pathway. Monoammonium glycyrrhizinate may be a potential therapeutic reagent for ALI.

scholarly journals Mesenchymal Stem Cells Attenuate Acute Lung Injury in Mice Partly by Suppressing Alveolar Macrophage Activation in a PGE2-dependent Manner

2021 ◽  
Author(s):  
Gaojian Wang ◽  
Yaping Zhang ◽  
Nianqiang Hu ◽  
Qinxue Liu ◽  
Fengjie Ma ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Alveolar Macrophage ◽  
Alveolar Macrophages ◽  
Macrophage Activation ◽  
Rna Seq ◽  
Ep4 Receptor ◽  
Pge2 Receptor ◽  
Cox2 Inhibitor

Abstract Background: Mesenchymal stem cell have shown therapeutic effect on acute lung injury, MSC could be activated when added to inflammatory environment and in turn suppress inflammation, yet the mechanism is complex and not understood. Methods: To determine the effect of MSC on ALI and alveolar macrophage activation, MSCs were administered to ALI mice and co-cultured with activated MH-S cells (alveolar macrophage cell line). To find the genes critical for MSC’s immunosuppressive effects, rest and activated MSCs induced by inflammatory MH-S cells were harvested for RNA-seq. To prove that PGE2 participates in the immunosuppressive effects of MSC, COX2 inhibitor and PGE2 receptor antagonist were added to the co-culture system and administrated to ALI mice. Results: The intratracheal administration of MSCs attenuated ALI and suppressed alveolar macrophages activation in vivo, the activation of MH-S cells was also significantly reduced after co-culturing with MSCs in vitro. The RNA-seq data of rest and activated MSCs suggested that the Ptgs2 gene may play an important role in MSC exerting immunosuppressive effects. Correspondingly, we found that the COX2 protein and PGE2 released by activated MSCs were increased dramatically after co-culturing with MH-S. The use of COX2 inhibitor NS-398 restrained the secretion of PGE2 and reversed the suppressive effect on macrophages activation of MSCs in vitro. Furthermore, GW627368X, a selective antagonist of PGE2 receptor (EP4 receptor), also reversed the inhibitory effects of MSCs on alveolar macrophages and their protective effects on ALI mice.Conclusions: MSC attenuate ALI partly through suppressing alveolar macrophage activation via PGE2 binding to EP4 receptor.

Sodium houttuyfonate relieves acute lung injury by nano micellar carrier and inhibits mitogen-activated protein kinase and nuclear factor kappa-B activation in mice

2021 ◽  
Vol 11 (5) ◽  
pp. 781-788
Author(s):  
Kai Yang ◽  
Shushu Yan ◽  
Jian Xie ◽  
Fang Xie ◽  
Zhenzhen Zhao ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Vascular Permeability ◽  
Delivery System ◽  
Lung Tissue ◽  
Good Effect ◽  
Pulmonary Vascular Permeability ◽  
Cytokine Levels ◽  
And Oxidative Stress

Acute lung injury (ALI) is characterized by increased pulmonary vascular permeability in response to the accumulation of inflammatory cells, release of inflammatory cytokines, and activated oxidative stress. The present study was performed to investigate the effect of sodium houttuyfonate (SH), an extract of Houttuynia cordata, on inflammatory response and oxidative stress in ALI induced by lipopolysaccharides (LPS). Male C57BL/6 mice were randomly allocated to control, LPS, dimethyl sulfoxide (DMSO), and SH groups. The ALI model was established by intratracheal LPS injection. Lung tissue was collected 6 h after LPS injection for histopathological analysis, measurement of wet-to-dry ratio, myeloperoxidase (MPO) and oxidative stress levels, and the p38, jun N-terminal kinase (JNK), extracellular regulated kinase (ERK), and p65 phosphorylation levels. Bronchoalveolar fluid (BALF) was collected for the detection of protein concentration, MPO and cytokine levels. The histopathological test showed that SH significantly alleviates damage to pulmonary tissue. Improved vascular permeability was indicated by reduced BALF protein level and lung wet-to-dry ratio in the SH group. MPO levels were decreased in lung tissue and BALF. Oxidative stress and inflammatory responses were inhibited by SH, as indicated by MDA, SOD and cytokine levels. The MAPK and NF-KB pathways were inhibited as shown by the attenuated phosphorylation of p38, JNK, ERK and p65. Sodium houttuyfonate exhibited a protective role against LPS-induced lung injury through anti-oxidative and anti-inflammatory effects. The MAPK and NF-K B pathways may be inhibited by sodium houttuyfonate. Sodium Houttuynin has a good effect on a variety of acute infectious diseases, but its solubility and stability are insufficient, which limits its efficacy. Nano delivery system can enhance the effective ingredients of traditional Chinese medicine, reduce the toxic and side effects of drugs, and improve their medicinal properties. Therefore, this paper adopts nano delivery system to assist drug use and improve research efficiency.

scholarly journals Role of Alveolar Macrophages in Candida-Induced Acute Lung Injury

2001 ◽  
Vol 8 (6) ◽  
pp. 1258-1262 ◽  
Author(s):  
Yutaka Kubota ◽  
Yoshinobu Iwasaki ◽  
Hidehiko Harada ◽  
Ichiro Yokomura ◽  
Mikio Ueda ◽  
...  
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Alveolar Macrophages ◽  
Weight Ratio ◽  
Dry Weight ◽  
Lavage Fluid ◽  
Secretory Cells ◽  
Disseminated Candidiasis ◽  
Cellular Source ◽  
Immunohistochemical Studies

ABSTRACT Recent studies have shown that alveolar macrophages (AMs) not only act as phagocytes but also play a central role as potent secretory cells in various lung diseases, including pneumonia and acute respiratory distress syndrome. The behavior of AMs during disseminated candidiasis, however, is insufficiently elucidated. This study is the first to report disseminated candidiasis in AM-depleted mice and to analyze the effect of AMs on Candida-induced acute lung injury. While all AM-sufficient mice died by day 2 after infection withCandida albicans, no mortality was observed among AM-depleted mice. Unexpectedly, the CFU numbers of C. albicans isolated from the lungs of AM-depleted mice were significantly higher than those for C. albicans isolated from AM-sufficient mice. The lung wet-to-dry weight ratio was lower for AM-depleted mice than for AM-sufficient mice, although this difference was not significant. We found that bronchoalveolar lavage fluid (BALF) from AM-depleted mice in candidemia contained fewer neutrophils than BALF from AM-sufficient mice. In addition, myeloperoxidase activities in lung homogenates of AM-depleted mice were significantly lower than those in homogenates of AM-sufficient mice. A significant decrease in levels of murine macrophage inflammatory protein 2 (MIP-2), a potent chemoattractant for neutrophils, was noted in lung homogenates from AM-depleted mice compared with levels in homogenates from AM-sufficient mice. Immunohistochemical studies using anti-MIP-2 antibodies revealed that AMs were the cellular source of MIP-2 within the lung during candidemia. We observed that AM depletion decreased levels of AM-derived neutrophil chemoattractant, alleviated acute lung injury during candidemia, and prolonged the survival of mice in candidemia, even though clearance of C. albicans from the lungs was reduced.

scholarly journals Gap Junction Channel Modulates Pulmonary Vascular Permeability through Calcium in Acute Lung Injury: An Experimental Study

Respiration ◽  
2010 ◽  
Vol 80 (3) ◽  
pp. 236-245 ◽  
Author(s):  
Jinzhou Zhang ◽  
Wen Wang ◽  
Jing Sun ◽  
Qiang Li ◽  
Jincheng Liu ◽  
...  
Keyword(s):  
Experimental Study ◽  
Acute Lung Injury ◽  
Lung Injury ◽  
Gap Junction ◽  
Vascular Permeability ◽  
Pulmonary Vascular Permeability ◽  
Gap Junction Channel

Cytoskeletal regulation of pulmonary vascular permeability

2001 ◽  
Vol 91 (4) ◽  
pp. 1487-1500 ◽  
Author(s):  
Steven M. Dudek ◽  
Joe G. N. Garcia
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Actin Cytoskeleton ◽  
Vascular Permeability ◽  
Barrier Function ◽  
Focal Adhesions ◽  
Pulmonary Vasculature ◽  
High Morbidity ◽  
Pulmonary Vascular Permeability ◽  
Cell Matrix

The endothelial cell (EC) lining of the pulmonary vasculature forms a semipermeable barrier between the blood and the interstitium of the lung. Disruption of this barrier occurs during inflammatory disease states such as acute lung injury and acute respiratory distress syndrome and results in the movement of fluid and macromolecules into the interstitium and pulmonary air spaces. These processes significantly contribute to the high morbidity and mortality of patients afflicted with acute lung injury. The critical importance of pulmonary vascular barrier function is shown by the balance between competing EC contractile forces, which generate centripetal tension, and adhesive cell-cell and cell-matrix tethering forces, which regulate cell shape. Both competing forces in this model are intimately linked through the endothelial cytoskeleton, a complex network of actin microfilaments, microtubules, and intermediate filaments, which combine to regulate shape change and transduce signals within and between EC. A key EC contractile event in several models of agonist-induced barrier dysfunction is the phosphorylation of regulatory myosin light chains catalyzed by Ca2+/calmodulin-dependent myosin light chain kinase and/or through the activity of the Rho/Rho kinase pathway. Intercellular contacts along the endothelial monolayer consist primarily of two types of complexes (adherens junctions and tight junctions), which link to the actin cytoskeleton to provide both mechanical stability and transduction of extracellular signals into the cell. Focal adhesions provide additional adhesive forces in barrier regulation by forming a critical bridge for bidirectional signal transduction between the actin cytoskeleton and the cell-matrix interface. Increasingly, the effects of mechanical forces such as shear stress and ventilator-induced stretch on EC barrier function are being recognized. The critical role of the endothelial cytoskeleton in integrating these multiple aspects of pulmonary vascular permeability provides a fertile area for the development of clinically important barrier-modulating therapies.

Vascular endothelial growth factor and related molecules in acute lung injury

2004 ◽  
Vol 97 (5) ◽  
pp. 1605-1617 ◽  
Author(s):  
Marco Mura ◽  
Claudia C. dos Santos ◽  
Duncan Stewart ◽  
Mingyao Liu
Keyword(s):  
Acute Lung Injury ◽  
Lung Injury ◽  
Vascular Permeability ◽  
Animal Experiments ◽  
Disease Process ◽  
Pulmonary Vascular Permeability ◽  
Capillary Membrane ◽  
Organ Systems ◽  
And Function

VEGFs and their receptors have been implicated in the regulation of vascular permeability in many organ systems, including the lung. Increased permeability and interstitial and pulmonary edema are prominent features of acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). Extrapolating data from other organ systems and animal experiments have suggested that overexpression of VEGF functions primarily as proinjurious molecules in the lung. Recent data, from animal models as well as from patients with ARDS, have shown decreased levels of VEGF in the lung. The role of VEGF and related molecules in ALI/ARDS is, therefore, controversial: what has become clear is that there are many unique features in the regulation of pulmonary vascular permeability and in VEGF expression in the lung. In this review, we explore a growing body of literature looking at the expression and function of VEGF and related molecules in different models of ALI and in patients with ALI/ARDS. Novel evidence points to a potential role of VEGF in promoting repair of the alveolar-capillary membrane during recovery from ALI/ARDS. Understanding the role of VEGF in this disease process is crucial for developing new therapeutic strategies for ALI/ARDS.

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