scholarly journals Effects of Aspergillus fumigatus Conidia on Apoptosis and Proliferation in an In Vitro Model of the Lung Microenvironment

2021 ◽  
Vol 9 (7) ◽  
pp. 1435
Author(s):  
Hisako Kushima ◽  
Toshiyuki Tsunoda ◽  
Taichi Matsumoto ◽  
Yoshiaki Kinoshita ◽  
Koichi Izumikawa ◽  
...  

Background/Aim: Aspergillus is often detected in respiratory samples from patients with chronic respiratory diseases, including pulmonary fibrosis, suggesting that it can easily colonize the airways. To determine the role of Aspergillus colonization in pulmonary fibrosis, we cultured human lung epithelial A549 cells or murine embryo fibroblast NIH/3T3 cells with Aspergillus conidia in 3D floating culture representing the microenvironment. Materials and Methods: Cells were cultured in two-dimensional (2D) and three-dimensional floating (3DF) culture with heat-inactivated Aspergillus fumigatus (AF) 293 conidia at an effector-to-target cell ratio of 1:10 (early-phase model) and 1:100 (colonization model), and RNA-sequencing and Western blots (WB) were performed. Results: AF293 conidia reduced A549 cell growth in 2D and 3DF cultures and induced apoptosis in A549 spheroids in 3DF culture. RNA-sequencing revealed the increased expression of genes associated with interferon-mediated antiviral responses including MX dymamin-like GTPase 1 (MX1). Interestingly, the decreased expression of genes associated with the cell cycle was observed with a high concentration of AF293 conidia. WB revealed that epithelial-mesenchymal transition was not involved. Notably, AF293 conidia increased NIH/3T3 growth only in 3DF culture without inducing an apoptotic reaction. RNA-sequencing revealed the increased expression of genes associated with interferon signalling, including MX2; however, the decreased expression of genes associated with the cell cycle was not observed. Conclusions: AF affects both apoptosis of epithelial cells and the growth of fibroblasts. A deeper understanding of the detailed mechanisms underlying Aspergillus-mediated signaling pathway in epithelial cells and fibroblasts will help us to understand the lung microenvironment.

2020 ◽  
Vol 4 (Supplement_2) ◽  
pp. 1531-1531
Author(s):  
Suyeon Oh ◽  
Young-Hee Kang

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.


2021 ◽  
Vol 22 (20) ◽  
pp. 11152
Author(s):  
Kai-Wei Chang ◽  
Xiang Zhang ◽  
Shih-Chao Lin ◽  
Yu-Chao Lin ◽  
Chia-Hsiang Li ◽  
...  

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.


2019 ◽  
Vol 20 (1) ◽  
Author(s):  
Chuyi Zhang ◽  
Xiaoping Zhu ◽  
Yifei Hua ◽  
Qian Zhao ◽  
Kaijing Wang ◽  
...  

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.


2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Zhenzhen Ma ◽  
Chunyan Ma ◽  
Qingfeng Zhang ◽  
Yang Bai ◽  
Kun Mu ◽  
...  

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.


2018 ◽  
Vol 46 (5) ◽  
pp. 1821-1834 ◽  
Author(s):  
Daishun Liu ◽  
Honglan Zhu ◽  
Ling Gong ◽  
Shenglan Pu ◽  
Yang Wu ◽  
...  

Background/Aims: Epithelial to mesenchymal transition (EMT) is a crucial process involved in pulmonary fibrosis. This study aimed to explore the role of histone deacetylases (HDACs) and endoplasmic reticulum (ER) stress in EMT in human lung epithelial cells. Methods: Human lung adenocarcinoma A549 cells were treated with bleomycin and tunicamycin to induce EMT. The proliferation of A549 cells was detected by MTT assay. The expression of HDACs and EMT markers was detected by PCR and Western blot analysis. The secretion of TGF-β1 and collagen I was examined by ELISA. Results: A549 cells switched from a cobblestone-like appearance to an elongated fibroblast like appearance after exposure to tunicamycin or bleomycin, accompanied by increased expression of N-cadherin, α-SMA and Collagen I. Meanwhile, GRP78 was upregulated in A549 cells exposed to tunicamycin or bleomycin. These changes induced by tunicamycin or bleomycin could be abrogated by 4-PBA. Moreover, tunicamycin and bleomycin promoted the expression of HDAC2 and HDAC6, and HDACs inhibitor SAHA abrogated the morphological and biochemical changes in A549 cells. 4-PBA and SAHA inhibited the upregulation of pulmonary fibrosis factors TGF-β1 and IL-32 and the activation of Smad pathway induced by tunicamycin or bleomycin. Conclusions: We provide the first evidence that tunicamycin and bleomycin induce ER stress and EMT in lung epithelial cells via the upregulation of HDACs. HDACs inhibitor could inhibit ER stress induced upregulation of pulmonary fibrosis factors and the activation of Smad pathway. HDACs inhibitors are promising agents for the therapy of pulmonary fibrosis.


2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Minrui Liang ◽  
Jiucun Wang ◽  
Haiyan Chu ◽  
Xiaoxia Zhu ◽  
Hang He ◽  
...  

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.


Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2639
Author(s):  
Frauke Stanke ◽  
Sabina Janciauskiene ◽  
Stephanie Tamm ◽  
Sabine Wrenger ◽  
Ellen Luise Raddatz ◽  
...  

The cystic fibrosis transmembrane conductance regulator (CFTR) gene is influenced by the fundamental cellular processes like epithelial differentiation/polarization, regeneration and epithelial–mesenchymal transition. Defects in CFTR protein levels and/or function lead to decreased airway surface liquid layer facilitating microbial colonization and inflammation. The SERPINA1 gene, encoding alpha1-antitrypsin (AAT) protein, is one of the genes implicated in CF, however it remains unknown whether AAT has any influence on CFTR levels. In this study we assessed CFTR protein levels in primary human lung epithelial cells grown at the air-liquid-interface (ALI) alone or pre-incubated with AAT by Western blots and immunohistochemistry. Histological analysis of ALI inserts revealed CFTR- and AAT-positive cells but no AAT-CFTR co-localization. When 0.5 mg/mL of AAT was added to apical or basolateral compartments of pro-inflammatory activated ALI cultures, CFTR levels increased relative to activated ALIs. This finding suggests that AAT is CFTR-modulating protein, albeit its effects may depend on the concentration and the route of administration. Human lung epithelial ALI cultures provide a useful tool for studies in detail how AAT or other pharmaceuticals affect the levels and activity of CFTR.


2018 ◽  
Vol 16 (1) ◽  
pp. 407-414
Author(s):  
Rui-qin Li ◽  
Bai-yan Wang ◽  
Yu-wen Ding ◽  
Rui Zhang ◽  
Jun-xia Zhang ◽  
...  

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.


2019 ◽  
Vol 6 (3) ◽  
pp. 70 ◽  
Author(s):  
Mao Komai ◽  
Karin Mihira ◽  
Akinori Shimada ◽  
Ikumi Miyamoto ◽  
Kikumi Ogihara ◽  
...  

Silicosis, caused by the inhalation of crystalline silicon dioxide or silica, is one of the most severe occupational diseases. Persistent inflammation and progressive massive pulmonary fibrosis are the most common histological changes caused by silicosis. Association of epithelial-mesenchymal transition (EMT) of hyperplastic type II epithelial cells with the fibrotic events of pulmonary fibrosis has been suggested in in vitro silica-exposed cultured cell models, patients with idiopathic pulmonary fibrosis, and bleomycin-induced experimental models. Histological features of EMT, however, are not fully described in silicotic lungs in in vivo. The purpose of this study was to demonstrate EMT of hyperplastic type II epithelial cells in the developmental process of progressive massive pulmonary fibrosis in the lungs of rats exposed to silica. F344 female rats were intratracheally instilled with 20 mg of crystalline silica (Min-U-Sil-5), followed by sacrifice at 1, 3, 6, and 12 months after instillation. Fibrosis, characterized by the formation of silicotic nodules, progressive massive fibrosis, and diffuse interstitial fibrosis, was observed in the lungs of the treated rats; the effects of fibrosis intensified in a time-dependent manner. Hyperplasia of the type II epithelial cells, observed in the massive fibrotic lesions, dominated in the lungs of rats at 6 and 12 months after the treatment. Immunohistochemistry of the serial sections of the lung tissues demonstrated positive labeling for cytokeratin, vimentin, and α-smooth muscle actin in spindle cells close to the foci of hyperplasia of type II epithelial cells. Spindle cells, which exhibited features of both epithelial cells and fibroblasts, were also demonstrated with bundles of collagen fibers in the fibrotic lesions, using electron microscopy. Increased expression of TGF-β was shown by Western blotting and immunohistochemistry in the lungs of the treated rats. These findings suggested that enhanced TGF-β expression and EMT of hyperplastic type II epithelial cells are involved in the development process of progressive massive pulmonary fibrosis during silicosis.


2021 ◽  
Vol 12 ◽  
Author(s):  
Yingying Yang ◽  
Lu Ding ◽  
Tingting Bao ◽  
Yaxin Li ◽  
Jing Ma ◽  
...  

Pulmonary fibrosis (PF) is one of the pathologic changes in COVID-19 patients in convalescence, and it is also a potential long-term sequela in severe COVID-19 patients. Qimai Feiluoping decoction (QM) is a traditional Chinese medicine formula recommended in the Chinese national medical program for COVID-19 convalescent patients, and PF is one of its indications. Through clinical observation, QM was found to improve the clinical symptoms and pulmonary function and reduce the degree of PF of COVID-19 convalescent patients. To further explore the pharmacological mechanisms and possible active components of QM in anti-PF effect, UHPLC/Q-TOF-MS was used to analyze the composition of the QM extract and the active components that can be absorbed into the blood, leading to the identification of 56 chemical compounds and 10 active components. Then, network pharmacology was used to predict the potential mechanisms and targets of QM; it predicted that QM exerts its anti-PF effects via the regulation of the epithelial–mesenchymal transition (EMT), extracellular matrix (ECM) degradation, and TGF-β signaling pathway. Finally, TGF-β1–induced A549 cells were used to verify and explore the pharmacological effects of QM and found that QM could inhibit the proliferation of TGF-β1–induced A549 cells, attenuate EMT, and promote ECM degradation by inhibiting the TGF-β/Smad3 pathway.


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