scholarly journals Aesculetin Attenuates Pulmonary Fibrosis Induced by Close Contact of Macrophages with Alveolar Epithelial Cells

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1531-1531
Author(s):  
Suyeon Oh ◽  
Young-Hee Kang
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
A549 Cells ◽  
Conditioned Media ◽  
Alveolar Epithelial Cells ◽  
Alveolar Cells ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial ◽  
Funding Sources ◽  
E Cadherin

Abstract Objectives Pulmonary fibrosis is a disease in which lung tissues become fibrous and causes severe respiratory disturbances. Various stimuli induce infiltration of macrophages to the respiratory tract. These macrophages secrete various inflammatory cytokines leading to development of pulmonary fibrosis via epithelial–mesenchymal transition (EMT) process. Aesculetin, a major component of Sancho tree and Chicory, is known to have antioxidant and anti-inflammatory effects in the vascular and immune system. Methods Human alveolar basal epithelial A549 cells were cultured in conditioned media of THP-1 monocyte-derived macrophages for 24 h. Aesculetin at the concentrations of 1–20 μM did not show cytotoxicity of A549 cells. Alveolar epithelial cells were incubated with interleukin (IL)-8. Western blotting examined EMT-associated fibrotic proteins from A549 cell lysates. Matrix metalloproteinase (MMP) activity was measured with gelatin zymography. In addition, inflammation- and fibrosis-related cytokines were measured by using ELISA kits. Results The epithelial markers of E-cadherin and ZO-1 were reduced in cells exposed to macrophage-conditioned media containing IL-8 and TNF-α. Macrophage-conditioned media enhanced expression of the mesenchymal fibrotic markers of α-smooth muscle actin (α-SMA), vimentin and fibronectin, and the fibrotic proteins of collagen I and collagen IV were enhanced. However, ≥10 μM aesculetin reciprocally manipulated the expression levels of these proteins of A549 cells. In addition, macrophage-conditioned media enhanced the expression and activity of MT1-MMP, MMP-2 and MMP-9. In contrast, the expression of tissue inhibitor of metalloproteinases (TIMP)-1 and TIMP-2 were reduced by exposure of alveolar cells to conditioned media. Proinflammatory and chemotactic IL-8 reduced E-cadherin and conversely enhanced N-cadherin and α-SMA in A549 cells, which was reciprocally modulated by ≥ 10 μM aesculetin. These results demonstrate that aesculetin may ameliorate EMT-associated pulmonary fibrosis caused by contact of blood-derived macrophages and alveolar cells. Conclusions Aesculetin maybe a promising agent treating progressive pulmonary disorders owing to macrophage-mediated inflammation. Funding Sources No funding sources to report.

scholarly journals Atractylodin Suppresses TGF-β-Mediated Epithelial-Mesenchymal Transition in Alveolar Epithelial Cells and Attenuates Bleomycin-Induced Pulmonary Fibrosis in Mice

2021 ◽  
Vol 22 (20) ◽  
pp. 11152
Author(s):  
Kai-Wei Chang ◽  
Xiang Zhang ◽  
Shih-Chao Lin ◽  
Yu-Chao Lin ◽  
Chia-Hsiang Li ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Lung Injury ◽  
Epithelial Mesenchymal Transition ◽  
A549 Cells ◽  
Alveolar Epithelial Cells ◽  
Collagen Deposition ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial ◽  
Tgf Β1

Idiopathic pulmonary fibrosis (IPF) is characterized by fibrotic change in alveolar epithelial cells and leads to the irreversible deterioration of pulmonary function. Transforming growth factor-beta 1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) in type 2 lung epithelial cells contributes to excessive collagen deposition and plays an important role in IPF. Atractylodin (ATL) is a kind of herbal medicine that has been proven to protect intestinal inflammation and attenuate acute lung injury. Our study aimed to determine whether EMT played a crucial role in the pathogenesis of pulmonary fibrosis and whether EMT can be utilized as a therapeutic target by ATL treatment to mitigate IPF. To address this topic, we took two steps to investigate: 1. Utilization of anin vitro EMT model by treating alveolar epithelial cells (A549 cells) with TGF-β1 followed by ATL treatment for elucidating the underlying pathways, including Smad2/3 hyperphosphorylation, mitogen-activated protein kinase (MAPK) pathway overexpression, Snail and Slug upregulation, and loss of E-cadherin. Utilization of an in vivo lung injury model by treating bleomycin on mice followed by ATL treatment to demonstrate the therapeutic effectiveness, such as, less collagen deposition and lower E-cadherin expression. In conclusion, ATL attenuates TGF-β1-induced EMT in A549 cells and bleomycin-induced pulmonary fibrosis in mice.

scholarly journals YY1 mediates TGF-β1-induced EMT and pro-fibrogenesis in alveolar epithelial cells

2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Chuyi Zhang ◽  
Xiaoping Zhu ◽  
Yifei Hua ◽  
Qian Zhao ◽  
Kaijing Wang ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Epithelial Mesenchymal Transition ◽  
A549 Cells ◽  
Alveolar Epithelial Cells ◽  
Lung Epithelial Cells ◽  
Lung Damage ◽  
Type Ii ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial

Abstract Pulmonary fibrosis is a chronic, progressive lung disease associated with lung damage and scarring. The pathological mechanism causing pulmonary fibrosis remains unknown. Emerging evidence suggests prominent roles of epithelial–mesenchymal transition (EMT) of alveolar epithelial cells (AECs) in myofibroblast formation and progressive pulmonary fibrosis. Our previous work has demonstrated the regulation of YY1 in idiopathic pulmonary fibrosis and pathogenesis of fibroid lung. However, the specific function of YY1 in AECs during the pathogenesis of pulmonary fibrosis is yet to be determined. Herein, we found the higher level of YY1 in primary fibroblasts than that in primary epithelial cells from the lung of mouse. A549 and BEAS-2B cells, serving as models for type II alveolar pulmonary epithelium in vitro, were used to determine the function of YY1 during EMT of AECs. TGF-β-induced activation of the pro-fibrotic program was applied to determine the role YY1 may play in pro-fibrogenesis of type II alveolar epithelial cells. Upregulation of YY1 was associated with EMT and pro-fibrotic phenotype induced by TGF-β treatment. Targeted knockdown of YY1 abrogated the EMT induction by TGF-β treatment. Enforced expression of YY1 can partly mimic the TGF-β-induced pro-fibrotic change in either A549 cell line or primary alveolar epithelial cells, indicating the induction of YY1 expression may mediate the TGF-β-induced EMT and pro-fibrosis. In addition, the translocation of NF-κB p65 from the cytoplasm to the nucleus was demonstrated in A549 cells after TGF-β treatment and/or YY1 overexpression, suggesting that NF-κB-YY1 signaling pathway regulates pulmonary fibrotic progression in lung epithelial cells. These findings will shed light on the better understanding of mechanisms regulating pro-fibrogenesis in AECs and pathogenesis of lung fibrosis.

scholarly journals Role of CXCL16 in BLM-induced epithelial–mesenchymal transition in human A549 cells

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhenzhen Ma ◽  
Chunyan Ma ◽  
Qingfeng Zhang ◽  
Yang Bai ◽  
Kun Mu ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Epithelial Mesenchymal Transition ◽  
A549 Cells ◽  
Alveolar Epithelial Cells ◽  
Alveolar Type ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial ◽  
Tgf Β1

AbstractAlveolar epithelial cells play an essential role in the initiation and progression of pulmonary fibrosis, and the occurrence of epithelial–mesenchymal transition (EMT) may be the early events of pulmonary fibrosis. Recent studies have shown chemokines are involved in the complex process of EMT, and CXC chemokine ligand 16 (CXCL16) is also associated with many fibrosis-related diseases. However, whether CXCL16 is dysregulated in alveolar epithelial cells and the role of CXCL16 in modulating EMT in pulmonary fibrosis has not been reported. In this study, we found that CXCL16 and its receptor C-X-C motif chemokine receptor 6 (CXCR6) were upregulated in bleomycin induced EMT in human alveolar type II-like epithelial A549 cells. Synergistic effect of CXCL16 and bleomycin in promoting EMT occurrence, extracellular matrix (ECM) excretion, as well as the pro-inflammatory and pro-fibrotic cytokines productions in A549 cells were observed, and those biological functions were impaired by CXCL16 siRNA. We further confirmed that CXCL16 regulated EMT in A549 cells via the TGF-β1/Smad3 pathways. These results indicated that CXCL16 could promote pulmonary fibrosis by promoting the process of EMT via the TGF-β1/Smad3 signaling pathway.

scholarly journals Interleukin-22 Inhibits Bleomycin-Induced Pulmonary Fibrosis

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Minrui Liang ◽  
Jiucun Wang ◽  
Haiyan Chu ◽  
Xiaoxia Zhu ◽  
Hang He ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Epithelial To Mesenchymal Transition ◽  
Alveolar Epithelial Cell ◽  
Smooth Muscle Actin ◽  
A549 Cells ◽  
Alveolar Epithelial Cells ◽  
Epithelial Cell Line ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial

Pulmonary fibrosis is a progressive and fatal fibrotic disease of the lungs with unclear etiology. Recent insight has suggested that early injury/inflammation of alveolar epithelial cells could lead to dysregulation of tissue repair driven by multiple cytokines. Although dysregulation of interleukin- (IL-) 22 is involved in various pulmonary pathophysiological processes, the role of IL-22 in fibrotic lung diseases is still unclear and needs to be further addressed. Here we investigated the effect of IL-22 on alveolar epithelial cells in the bleomycin- (BLM-) induced pulmonary fibrosis. BLM-treated mice showed significantly decreased level of IL-22 in the lung. IL-22 producedγδT cells were also decreased significantly both in the tissues of lungs and spleens. Administration of recombinant human IL-22 to alveolar epithelial cell line A549 cells ameliorated epithelial to mesenchymal transition (EMT) and partially reversed the impaired cell viability induced by BLM. Furthermore, blockage of IL-22 deteriorated pulmonary fibrosis, with elevated EMT marker (α-smooth muscle actin (α-SMA)) and overactivated Smad2. Our results indicate that IL-22 may play a protective role in the development of BLM-induced pulmonary fibrosis and may suggest IL-22 as a novel immunotherapy tool in treating pulmonary fibrosis.

scholarly journals Serum containing drugs of Gua Lou Xie Bai decoction (GLXB-D) can inhibit TGF-β1-Induced Epithelial to Mesenchymal Transition (EMT) in A549 Cells

2018 ◽  
Vol 16 (1) ◽  
pp. 407-414
Author(s):  
Rui-qin Li ◽  
Bai-yan Wang ◽  
Yu-wen Ding ◽  
Rui Zhang ◽  
Jun-xia Zhang ◽  
...  
Keyword(s):  
Pulmonary Fibrosis ◽  
Transforming Growth Factor ◽  
A549 Cells ◽  
Alveolar Epithelial Cells ◽  
Collagen I ◽  
Potential Candidate ◽  
Mesenchymal Transition ◽  
Thiazolyl Blue Tetrazolium Bromide ◽  
Tgf Β1 ◽  
E Cadherin

AbstractThe present study explores the mechanism of resistance to pulmonary fibrosis by observing the possible effects of serum containing drugs prepared from Gua Lou Xie Bai decoction (GLXB-D) on transforming growth factor beta 1 (TGF-β1) induced Epithelial-mesenchymal transition (EMT) of A549 human alveolar epithelial cells. The inhibition rate was observed with the help of thiazolyl blue tetrazolium bromide (MTT) in 24 h and 48 h treated cells. Inverted microscope and transmission electron microscope (TEM) were used to study the changes in the morphology and ultrastructure of the cells. The expressions of E-cadherin and Vimentin were comparatively analyzed by Western blotting, while the expressions of Collagen I and III were analyzed by ELISA. The data obtained indicated that the expression of epithelial marker E-cadherin was decreased, while the expressions of EMT markers such as Vimentin and Collagen I and III were increased in 24 h after TGF-β1 induction. However, the serum containing drugs of GLXB-D were found to inhibit the TGF-β1 induced proliferation of cells, increase the expression of E-cadherin and decrease the expression of Vimentin, collagen I and III. In conclusion, the serum containing drugs of GLXB-D effectively reduced pulmonary fibrosis, mainly via the reversal of EMT induction by TGF-β1. Thus, it can be considered as a potential candidate for the development of better treatment methods for pulmonary fibrosis.

scholarly journals Epithelial–Mesenchymal Transition in the Pathogenesis of Idiopathic Pulmonary Fibrosis

Medicina ◽  
2019 ◽  
Vol 55 (4) ◽  
pp. 83 ◽  
Author(s):  
Francesco Salton ◽  
Maria Volpe ◽  
Marco Confalonieri
Keyword(s):  
Epithelial Cells ◽  
Idiopathic Pulmonary Fibrosis ◽  
Pulmonary Fibrosis ◽  
Epithelial Mesenchymal Transition ◽  
Treatment Options ◽  
Alveolar Epithelium ◽  
Alveolar Epithelial Cells ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial ◽  
Serious Disease

Idiopathic pulmonary fibrosis (IPF) is a serious disease of the lung, which leads to extensive parenchymal scarring and death from respiratory failure. The most accepted hypothesis for IPF pathogenesis relies on the inability of the alveolar epithelium to regenerate after injury. Alveolar epithelial cells become apoptotic and rare, fibroblasts/myofibroblasts accumulate and extracellular matrix (ECM) is deposited in response to the aberrant activation of several pathways that are physiologically implicated in alveologenesis and repair but also favor the creation of excessive fibrosis via different mechanisms, including epithelial–mesenchymal transition (EMT). EMT is a pathophysiological process in which epithelial cells lose part of their characteristics and markers, while gaining mesenchymal ones. A role for EMT in the pathogenesis of IPF has been widely hypothesized and indirectly demonstrated; however, precise definition of its mechanisms and relevance has been hindered by the lack of a reliable animal model and needs further studies. The overall available evidence conceptualizes EMT as an alternative cell and tissue normal regeneration, which could open the way to novel diagnostic and prognostic biomarkers, as well as to more effective treatment options.

scholarly journals Aesculetin Inhibits Pulmonary Fibrosis by Epithelial-to-mesenchymal Transition(EMT) in a Alveolar Epithelial Cell (P06-068-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Su Yeon Oh ◽  
Young-Hee Kang
Keyword(s):  
Pulmonary Fibrosis ◽  
Epithelial To Mesenchymal Transition ◽  
Epithelial Mesenchymal Transition ◽  
Alveolar Epithelial Cell ◽  
Smooth Muscle Actin ◽  
Pulmonary Inflammation ◽  
A549 Cells ◽  
Conditioned Media ◽  
Alveolar Cells ◽  
Mesenchymal Transition

Abstract Objectives Pulmonary fibrosis is a disease in which lung tissues become fibrous and causes severe respiratory disturbances. Various stimuli induce infiltration of macrophages to the respiratory tract. These macrophages secrete various cytokines leading to development of pulmonary fibrosis. Aesculetin, a major component of Sancho tree and Chicory, is known to have antioxidant and anti-inflammatory effects in the vascular and immune system. However, its effect on pulmonary fibrosis has been poorly understood. The current study investigated that aesculetin inhibited pulmonary fibrosis caused by infiltration of monocyte-derived macrophages. Methods To differentiate to monocyte-derived macrophages, THP-1 human mononuclear cell line was treated with 50 ng/ml phorbol myristate acetate (PMA) for 24 h. Culture conditioned media were harvested from macrophages cultured in the absence of PMA for 24 h. A549 human alveolar basal epithelial cells were cultured in the conditioned media for 24 h to induce alveolar fibrosis. Epithelial–mesenchymal transition (EMT)-associated fibrotic proteins were measured with Western blotting from A549 cell lysates. Results Aesculetin at the concentrations of 1–20 μM did not show any toxicity of A549 cells, evidence by MTT assay. When A549 cells were treated with conditioned media from monocyte-derived macrophages, the expression of mesenchymal fibrotic proteins of α-smooth muscle actin and fibronectin was highly enhanced. In contrast, ≥10 μM aesculetin inhibited the induction of these proteins of A549 cells. The expression of E-cadherin and Zonula occludens-1 was reduced in cells supplemented with conditioned media, while aesculetin promoted these epithelial phenotypic proteins in conditioned media-exposed alveolar cells. Conclusions These results demonstrate that aesculetin may ameliorate EMT-associated alveolar fibrosis caused by monocyte-derived macrophages infiltrated into the alveoli. Therefore, Aesculetin maybe a promising agent treating progressive pulmonary disorders owing to pulmonary inflammation. Funding Sources This work (Grants No. C0501612) was supported by project for Cooperative R&D between Industry, Academy, and Research Institute funded Korea Ministry of SMEs and Startups in 20.

scholarly journals Radiation Induces Pulmonary Fibrosis by Promoting the Fibrogenic Differentiation of Alveolar Stem Cells

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Lu-Kai Wang ◽  
Tsai-Jung Wu ◽  
Ji-Hong Hong ◽  
Fang-Hsin Chen ◽  
John Yu ◽  
...  
Keyword(s):  
Stem Cells ◽  
Epithelial Cells ◽  
Epithelial Mesenchymal Transition ◽  
Tissue Growth ◽  
Alveolar Epithelial Cells ◽  
Type I ◽  
Alveolar Cells ◽  
Mesenchymal Transition ◽  
Alveolar Epithelial ◽  
Radiation Induced

The lung is a radiosensitive organ, which imposes limits on the therapeutic dose in thoracic radiotherapy. Irradiated alveolar epithelial cells promote radiation-related pneumonitis and fibrosis. However, the role of lung stem cells (LSCs) in the development of radiation-induced lung injury is still unclear. In this study, we found that both LSCs and LSC-derived type II alveolar epithelial cells (AECII) can repair radiation-induced DNA double-strand breaks, but the irradiated LSCs underwent growth arrest and cell differentiation faster than the irradiated AECII cells. Moreover, radiation drove LSCs to fibrosis as shown with the elevated levels of markers for epithelial-mesenchymal transition and myofibroblast (α-smooth muscle actin (α-SMA)) differentiation in in vitro and ex vivo studies. Increased gene expressions of connective tissue growth factor and α-SMA were found in both irradiated LSCs and alveolar cells, suggesting that radiation could induce the fibrogenic differentiation of LSCs. Irradiated LSCs showed an increase in the expression of surfactant protein C (SP-C), the AECII cell marker, and α-SMA, and irradiated AECII cells expressed SP-C and α-SMA. These results indicated that radiation induced LSCs to differentiate into myofibroblasts and AECII cells; then, AECII cells differentiated further into either myofibroblasts or type I alveolar epithelial cells (AECI). In conclusion, our results revealed that LSCs are sensitive to radiation-induced cell damage and may be involved in radiation-induced lung fibrosis.

scholarly journals The NLRP3-Inflammasome-Caspase-1 Pathway Is Upregulated in Idiopathic Pulmonary Fibrosis and Acute Exacerbations and Is Inducible by Apoptotic A549 Cells

2021 ◽  
Vol 12 ◽  
Author(s):  
Benedikt Jäger ◽  
Benjamin Seeliger ◽  
Oliver Terwolbeck ◽  
Gregor Warnecke ◽  
Tobias Welte ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Idiopathic Pulmonary Fibrosis ◽  
Pulmonary Fibrosis ◽  
Nlrp3 Inflammasome ◽  
Cathepsin B ◽  
A549 Cells ◽  
Alveolar Epithelial Cells ◽  
Alveolar Epithelial ◽  
Caspase 1 ◽  
Acute Exacerbations

Idiopathic pulmonary fibrosis (IPF) is a relentlessly progressive disease harboring significant morbidity and mortality despite recent advances in therapy. Regardless of disease severity acute exacerbations (IPF-AEs) may occur leading to considerable loss of function and are the leading cause of death in IPF. Histologic features of IPF-AE are very similar to acute respiratory distress syndrome (ARDS), but the underlying mechanisms are incompletely understood. We investigated the role of the NLRP3 inflammasome in IPF and IPF-AE. Bronchoalveolar lavage (BAL) cells were sampled from patients with IPF (n = 32), IPF-AE (n = 10), ARDS (n = 7) and healthy volunteers (HV, n = 37) and the NLRP3-inflammasome was stimulated in-vitro. We found the NLRP3 inflammasome to be hyper-inducible in IPF compared to HV with increased IL-1ß and pro-IL-1ß levels on ELISA upon stimulation as well as increased caspase-1 activity measured by caspase-1p20 immunoblotting. In IPF-AE, IL-1ß was massively elevated to an extent similar to ARDS. To evaluate potential mechanisms, we co-cultured BAL cells with radiated A549 cells (a model to simulate apoptotic alveolar epithelial cells), which led to increased NLRP3 mRNA expression and increased caspase-1 dependent IL-1ß production. In the presence of a reactive oxygen species (ROS) inhibitor (diphenyleneiodonium) and a cathepsin B inhibitor (E64D), NLRP3 expression was suppressed indicating that induction of NLRP3 activation following efferocytosis of apoptotic A549 cells is mediated via ROS and cathepsin-B. In summary, we present evidence of involvement of the NLRP3 inflammasome-caspase pathway in the pathogenesis of IPF-AE, similarly to ARDS, which may be mediated by efferocytosis of apoptotic alveolar epithelial cells in IPF.

scholarly journals The Efficiency of the Translocation of Mycobacterium tuberculosis across a Bilayer of Epithelial and Endothelial Cells as a Model of the Alveolar Wall Is a Consequence of Transport within Mononuclear Phagocytes and Invasion of Alveolar Epithelial Cells

2002 ◽  
Vol 70 (1) ◽  
pp. 140-146 ◽  
Author(s):  
Luiz E. Bermudez ◽  
Felix J. Sangari ◽  
Peter Kolonoski ◽  
Mary Petrofsky ◽  
Joseph Goodman
Keyword(s):  
Endothelial Cells ◽  
Mycobacterium Tuberculosis ◽  
Epithelial Cells ◽  
A549 Cells ◽  
Mononuclear Phagocytes ◽  
Alveolar Epithelial Cells ◽  
Alveolar Wall ◽  
Alveolar Cells ◽  
Initial Inoculum ◽  
Alveolar Epithelial

ABSTRACT The mechanism(s) by which Mycobacterium tuberculosis crosses the alveolar wall to establish infection in the lung is not well known. In an attempt to better understand the mechanism of translocation and create a model to study the different stages of bacterial crossing through the alveolar wall, we established a two-layer transwell system. M. tuberculosis H37Rv was evaluated regarding the ability to cross and disrupt the membrane. M. tuberculosis invaded A549 type II alveolar cells with an efficiency of 2 to 3% of the initial inoculum, although it was not efficient in invading endothelial cells. However, bacteria that invaded A549 cells were subsequently able to be taken up by endothelial cells with an efficiency of 5 to 6% of the inoculum. When incubated with a bicellular transwell monolayer (epithelial and endothelial cells), M. tuberculosis translocated into the lower chamber with efficiency (3 to 4%). M. tuberculosis was also able to efficiently translocate across the bicellular layer when inside monocytes. Infected monocytes crossed the barrier with greater efficiency when A549 alveolar cells were infected with M. tuberculosis than when A549 cells were not infected. We identified two potential mechanisms by which M. tuberculosis gains access to deeper tissues, by translocating across epithelial cells and by traveling into the blood vessels within monocytes.

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