Increased Cell Surface Fas Expression Is Necessary and Sufficient To Sensitize Lung Fibroblasts to Fas Ligation-Induced Apoptosis: Implications for Fibroblast Accumulation in Idiopathic Pulmonary Fibrosis

AbstractThe family of RNA-binding proteins (RBP) functions as a crucial regulator of multiple biological processes and diseases. However, RBP function in the clinical setting of idiopathic pulmonary fibrosis (IPF) is still unknown. We developed a practical in silico screening approach for the characterization of RBPs using multi-sources data information and comparative molecular network bioinformatics followed by wet-lab validation studies. Data mining of bulk RNA-Sequencing data of tissues of patients with IPF identified Quaking (QKI) as a significant downregulated RBP. Cell-type specific expression was confirmed by single-cell RNA-Sequencing analysis of IPF patient data. We systematically analyzed the molecular interaction network around QKI and its functional interplay with microRNAs (miRs) in human lung fibroblasts and discovered a novel regulatory miR-506-QKI axis contributing to the pathogenesis of IPF. The in silico results were validated by in-house experiments applying model systems of miR and lung biology. This study supports an understanding of the intrinsic molecular mechanisms of IPF regulated by the miR-506-QKI axis. Initially applied to human lung disease, the herein presented integrative in silico data mining approach can be adapted to other disease entities, underlining its practical relevance in RBP research.

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LTBP2 is secreted from lung myofibroblasts and is a potential biomarker for idiopathic pulmonary fibrosis

Clinical Science ◽

10.1042/cs20180435 ◽

2018 ◽

Vol 132 (14) ◽

pp. 1565-1580 ◽

Cited By ~ 6

Author(s):

Yasunori Enomoto ◽

Sayomi Matsushima ◽

Kiyoshi Shibata ◽

Yoichiro Aoshima ◽

Haruna Yagi ◽

...

Keyword(s):

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Transforming Growth Factor ◽

Smooth Muscle Actin ◽

Bootstrap Method ◽

Transforming Growth Factor Β ◽

Lung Fibroblasts ◽

Potential Biomarker ◽

Fibrotic Process ◽

Mouse Lungs

Although differentiation of lung fibroblasts into α-smooth muscle actin (αSMA)-positive myofibroblasts is important in the progression of idiopathic pulmonary fibrosis (IPF), few biomarkers reflecting the fibrotic process have been discovered. We performed microarray analyses between FACS-sorted steady-state fibroblasts (lineage (CD45, TER-119, CD324, CD31, LYVE-1, and CD146)-negative and PDGFRα-positive cells) from untreated mouse lungs and myofibroblasts (lineage-negative, Sca-1-negative, and CD49e-positive cells) from bleomycin-treated mouse lungs. Amongst several genes up-regulated in the FACS-sorted myofibroblasts, we focussed on Ltbp2, the gene encoding latent transforming growth factor-β (TGF-β) binding protein-2 (LTBP2), because of the signal similarity to Acta2, which encodes αSMA, in the clustering analysis. The up-regulation was reproduced at the mRNA and protein levels in human lung myofibroblasts induced by TGF-β1. LTBP2 staining in IPF lungs was broadly positive in the fibrotic interstitium, mainly as an extracellular matrix (ECM) protein; however, some of the αSMA-positive myofibroblasts were also stained. Serum LTBP2 concentrations, evaluated using ELISA, in IPF patients were significantly higher than those in healthy volunteers (mean: 21.4 compared with 12.4 ng/ml) and showed a negative correlation with % predicted forced vital capacity (r = −0.369). The Cox hazard model demonstrated that serum LTBP2 could predict the prognosis of IPF patients (hazard ratio for death by respiratory events: 1.040, 95% confidence interval: 1.026–1.054), which was validated using the bootstrap method with 1000-fold replication. LTBP2 is a potential prognostic blood biomarker that may reflect the level of differentiation of lung fibroblasts into myofibroblasts in IPF.

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Mode of action of nintedanib in the treatment of idiopathic pulmonary fibrosis

European Respiratory Journal ◽

10.1183/09031936.00174914 ◽

2015 ◽

Vol 45 (5) ◽

pp. 1434-1445 ◽

Cited By ~ 284

Author(s):

Lutz Wollin ◽

Eva Wex ◽

Alexander Pautsch ◽

Gisela Schnapp ◽

Katrin E. Hostettler ◽

...

Keyword(s):

Growth Factor ◽

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Tyrosine Kinases ◽

Cell Injury ◽

Transforming Growth Factor ◽

Alveolar Epithelial Cell ◽

Phase Iii ◽

Lung Fibroblasts

Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal disease characterised by fibrosis of the lung parenchyma and loss of lung function. Although the pathogenic pathways involved in IPF have not been fully elucidated, IPF is believed to be caused by repetitive alveolar epithelial cell injury and dysregulated repair, in which there is uncontrolled proliferation of lung fibroblasts and differentiation of fibroblasts into myofibroblasts, which excessively deposit extracellular matrix (ECM) proteins in the interstitial space. A number of profibrotic mediators including platelet-derived growth factor (PDGF), fibroblast growth factor (FGF) and transforming growth factor-β are believed to play important roles in the pathogenesis of IPF. Nintedanib is a potent small molecule inhibitor of the receptor tyrosine kinases PDGF receptor, FGF receptor and vascular endothelial growth factor receptor. Data from in vitro studies have shown that nintedanib interferes with processes active in fibrosis such as fibroblast proliferation, migration and differentiation, and the secretion of ECM. In addition, nintedanib has shown consistent anti-fibrotic and anti-inflammatory activity in animal models of lung fibrosis. These data provide a strong rationale for the clinical efficacy of nintedanib in patients with IPF, which has recently been demonstrated in phase III clinical trials.

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Effect of nintedanib on hyaluronic acid metabolism in lung fibroblasts derived from patients with idiopathic pulmonary fibrosis

10.1183/13993003.congress-2015.pa3052 ◽

2015 ◽

Author(s):

Katrin Hostettler ◽

Eleni Papakonstantinou ◽

Ioannis Klagas ◽

Ioannis Bonovolias ◽

Michael Tamm ◽

...

Keyword(s):

Hyaluronic Acid ◽

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Acid Metabolism ◽

Lung Fibroblasts

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Compromised peroxisomes in idiopathic pulmonary fibrosis, a vicious cycle inducing a higher fibrotic response via TGF-β signaling

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1415111112 ◽

2015 ◽

Vol 112 (16) ◽

pp. E2048-E2057 ◽

Cited By ~ 53

Author(s):

Gani Oruqaj ◽

Srikanth Karnati ◽

Vijith Vijayan ◽

Lakshmi Kanth Kotarkonda ◽

Eistine Boateng ◽

...

Keyword(s):

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Transforming Growth Factor Beta ◽

Molecular Mechanisms ◽

Transforming Growth Factor ◽

Lung Fibroblasts ◽

Fibrotic Response ◽

Down Regulation ◽

Necrosis Factor Alpha ◽

Isolated Lung

Idiopathic pulmonary fibrosis (IPF) is a devastating disease, and its pathogenic mechanisms remain incompletely understood. Peroxisomes are known to be important in ROS and proinflammatory lipid degradation, and their deficiency induces liver fibrosis. However, altered peroxisome functions in IPF pathogenesis have never been investigated. By comparing peroxisome-related protein and gene expression in lung tissue and isolated lung fibroblasts between human control and IPF patients, we found that IPF lungs exhibited a significant down-regulation of peroxisomal biogenesis and metabolism (e.g., PEX13p and acyl-CoA oxidase 1). Moreover, in vivo the bleomycin-induced down-regulation of peroxisomes was abrogated in transforming growth factor beta (TGF-β) receptor II knockout mice indicating a role for TGF-β signaling in the regulation of peroxisomes. Furthermore, in vitro treatment of IPF fibroblasts with the profibrotic factors TGF-β1 or tumor necrosis factor alpha (TNF-α) was found to down-regulate peroxisomes via the AP-1 signaling pathway. Therefore, the molecular mechanisms by which reduced peroxisomal functions contribute to enhanced fibrosis were further studied. Direct down-regulation of PEX13 by RNAi induced the activation of Smad-dependent TGF-β signaling accompanied by increased ROS production and resulted in the release of cytokines (e.g., IL-6, TGF-β) and excessive production of collagen I and III. In contrast, treatment of fibroblasts with ciprofibrate or WY14643, PPAR-α activators, led to peroxisome proliferation and reduced the TGF-β–induced myofibroblast differentiation and collagen protein in IPF cells. Taken together, our findings suggest that compromised peroxisome activity might play an important role in the molecular pathogenesis of IPF and fibrosis progression, possibly by exacerbating pulmonary inflammation and intensifying the fibrotic response in the patients.

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Pathologic Proteolytic Processing of N-Cadherin as a Marker of Human Fibrotic Disease

Cells ◽

10.3390/cells11010156 ◽

2022 ◽

Vol 11 (1) ◽

pp. 156

Author(s):

Paul Durham Ferrell ◽

Kristianne Michelle Oristian ◽

Everett Cockrell ◽

Salvatore Vincent Pizzo

Keyword(s):

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Cell Surface ◽

Cell Lines ◽

Cell Adhesion Molecule ◽

Protein Processing ◽

Proteolytic Processing ◽

Fibrotic Disease ◽

Nonalcoholic Fatty Liver ◽

Murine Antibody

Prior research has implicated the involvement of cell adhesion molecule N-cadherin in tissue fibrosis and remodeling. We hypothesize that anomalies in N-cadherin protein processing are involved in pathological fibrosis. Diseased tissues associated with fibrosis of the heart, lung, and liver were probed for the precursor form of N-cadherin, pro-N-cadherin (PNC), by immunohistochemistry and compared to healthy tissues. Myofibroblast cell lines were analyzed for cell surface pro-N-cadherin by flow cytometry and immunofluorescent microscopy. Soluble PNC products were immunoprecipitated from patient plasmas and an enzyme-linked immunoassay was developed for quantification. All fibrotic tissues examined show aberrant PNC localization. Cell surface PNC is expressed in myofibroblast cell lines isolated from cardiomyopathy and idiopathic pulmonary fibrosis but not on myofibroblasts isolated from healthy tissues. PNC is elevated in the plasma of patients with cardiomyopathy (p ≤ 0.0001), idiopathic pulmonary fibrosis (p ≤ 0.05), and nonalcoholic fatty liver disease with cirrhosis (p ≤ 0.05). Finally, we have humanized a murine antibody and demonstrate that it significantly inhibits migration of PNC expressing myofibroblasts. Collectively, the aberrant localization of PNC is observed in all fibrotic tissues examined in our study and our data suggest a role for cell surface PNC in the pathogenesis of fibrosis.

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CoQ10 Enhances the Efficacy of Airway Basal Stem Cell Transplantation on Bleomycin-induced Idiopathic Pulmonary Fibrosis in Mice

10.21203/rs.3.rs-721105/v1 ◽

2021 ◽

Author(s):

Huanbin Liu ◽

Yidi Zhang ◽

Jinjun Jiang ◽

Yulong Luo ◽

Jingxin Zhao ◽

...

Keyword(s):

Oxidative Stress ◽

Idiopathic Pulmonary Fibrosis ◽

Pulmonary Fibrosis ◽

Pulmonary Inflammation ◽

Intratracheal Instillation ◽

Therapeutic Effects ◽

Protective Effects ◽

Induced Apoptosis ◽

Lung Regeneration

Abstract Background: Recent studies have demonstrated that airway basal stem cells (BCs) transplantation can ameliorate bleomycin-induced idiopathic pulmonary fibrosis (IPF) through lung regeneration promotion. However, BCs under oxidative stress in the alveolar microenvironment are poor in survival, causing unsatisfied efficacy of BCs transplantation. In this study, we investigated whether Coenzyme Q10(CoQ10) counteracts oxidative stress in the alveolar microenvironment, thus improved the efficacy of BCs transplantation for IPF treatment.Methods: The protective effects of CoQ10 on H2O2-induced BCs apoptosis and cytoplasmic reactive oxygen species (ROS) level were tested by flow cytometry in vitro. The therapeutic effects of BCs combined with CoQ10 were compared to a single BCs transplantation protocol in IPF treatment after two weeks and were evaluated by parameters including changes of body weight and survival rate, as well as various levels of pulmonary inflammation, α-SMA expression and hydroxyproline (HYP) in IPF mice lung tissues.Results: CoQ 10 preincubation with BCs (10 mM, 24 h) significantly reduced the late apoptosis of BCs and the number of oxidative stressful BCs as a result of H2O2 stimulation (1mM, 6h) in vitro. IPF mice models were constructed through bleomycin (5 mg/Kg) intratracheal instillation. Bleomycin-induced IPF mice showed weight loss continuously and mortality increased progressively during modeling. Serious pulmonary inflammatory cell infiltration, collagen fiber proliferation, and collagen protein deposition were observed in lung tissues of IPF mice. Though BCs transplantation alone improved indicators above in bleomycin-induced IPF mice to some extent, the combination with CoQ10 improved the transplantation efficacy and obtained better therapeutic effects.Conclusion：CoQ10 blocked H2O2-induced apoptosis of BCs and ROS production in vitro, and enhanced the efficacy of BCs transplantation on bleomycin-induced IPF in mice.

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