scholarly journals Depletion of Numb and Numblike in Murine Lung Epithelial Cells Ameliorates Bleomycin-Induced Lung Fibrosis by Inhibiting the β-Catenin Signaling Pathway

2021 ◽  
Vol 9 ◽  
Author(s):  
Alessandro Ianni ◽  
Michael Hofmann ◽  
Poonam Kumari ◽  
Shahriar Tarighi ◽  
Hamza M Al-Tamari ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Critical Role ◽  
Survival Rates ◽  
Lung Epithelial Cells ◽  
Alveolar Cells ◽  
Lung Epithelial ◽  
Type Ii Alveolar Cells ◽  
Underlying Mechanisms ◽  
Repeated Injury

Idiopathic pulmonary fibrosis (IPF) represents the most aggressive form of pulmonary fibrosis (PF) and is a highly debilitating disorder with a poorly understood etiology. The lung epithelium seems to play a critical role in the initiation and progression of the disease. A repeated injury of lung epithelial cells prompts type II alveolar cells to secrete pro-fibrotic cytokines, which induces differentiation of resident mesenchymal stem cells into myofibroblasts, thus promoting aberrant deposition of extracellular matrix (ECM) and formation of fibrotic lesions. Reactivation of developmental pathways such as the Wnt-β-catenin signaling cascade in lung epithelial cells plays a critical role in this process, but the underlying mechanisms are still enigmatic. Here, we demonstrate that the membrane-associated protein NUMB is required for pathological activation of β-catenin signaling in lung epithelial cells following bleomycin-induced injury. Importantly, depletion of Numb and Numblike reduces accumulation of fibrotic lesions, preserves lung functions, and increases survival rates after bleomycin treatment of mice. Mechanistically, we demonstrate that NUMB interacts with casein kinase 2 (CK2) and relies on CK2 to activate β-catenin signaling. We propose that pharmacological inhibition of NUMB signaling may represent an effective strategy for the development of novel therapeutic approaches against PF.

scholarly journals miR-34a promotes fibrosis in aged lungs by inducing alveolarepithelial dysfunctions

2017 ◽  
Vol 312 (3) ◽  
pp. L415-L424 ◽  
Author(s):  
Huachun Cui ◽  
Jing Ge ◽  
Na Xie ◽  
Sami Banerjee ◽  
Yong Zhou ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Lung Fibrosis ◽  
Critical Role ◽  
Lung Epithelial Cells ◽  
Lung Fibroblasts ◽  
Aged Population ◽  
Age Related ◽  
Micro Rnas ◽  
Lung Epithelial

Idiopathic pulmonary fibrosis is a well-known age-related disease. However, much less recognized has been the aging associated pathogenesis of this disorder. As we and others previously showed that dysregulation of micro-RNAs (miRNAs) was an important mechanism involved in pulmonary fibrosis, the role of these molecules in this pathology in the aged population has not been investigated (Cushing L, Kuang PP, Qian J, Shao F, Wu J, Little F, Thannickal VJ, Cardoso WV, Lü J. Am J Respir Cell Mol Biol 45: 287–294, 2011; Liu G, Friggeri A, Yang Y, Milosevic J, Ding Q, Thannickal VJ, Kaminski N, Abraham E. J Exp Med 207: 1589–1597, 2010; Pandit KV, Corcoran D, Yousef H, Yarlagadda M, Tzouvelekis A, Gibson KF, Konishi K, Yousem SA, Singh M, Handley D, Richards T, Selman M, Watkins SC, Pardo A, Ben-Yehudah A, Bouros D, Eickelberg O, Ray P, Benos PV, Kaminski N. Am J Respir Crit Care Med 182: 220–229, 2010). In this study, by using a lung fibrosis model established in old mice, we found that ablation of miR-34a protected aged animals from developing experimental lung fibrosis. miR-34a was upregulated in lung epithelial cells, but not in lung fibroblasts of aged mice, and miR-34a expression was further increased in epithelial cells of the fibrotic lungs of these old animals. We found that miR-34a induced dysfunctions in alveolar epithelial cells (AECs), as evidenced by increased cellular senescence and apoptosis and mitochondrial aberrations. More importantly, these abnormalities were attenuated in AECs of the fibrotic lungs of aged miR-34a−/− mice. We found that miR-34a targeted Sirt1, a master anti-aging regulator, and two key cell cycle modulators, E2F3 and cyclin E2, in lung epithelial cells, and the repression of these targets was relieved in miR-34a-deficient AECs. In summary, our data suggest that elevated AEC miR-34a plays a critical role in the pathogenesis of pulmonary fibrosis in the aged population. Our study also indicates miR-34a to be a more precise miRNA target for treating this disease that overwhelmingly affects people of advanced age.

scholarly journals Congenital Deletion of Nedd4-2 in Lung Epithelial Cells Causes Progressive Alveolitis and Pulmonary Fibrosis in Neonatal Mice

2021 ◽  
Vol 22 (11) ◽  
pp. 6146
Author(s):  
Dominik H. W. Leitz ◽  
Julia Duerr ◽  
Surafel Mulugeta ◽  
Ayça Seyhan Agircan ◽  
Stefan Zimmermann ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Growth Failure ◽  
Lung Epithelial Cells ◽  
Na Channel ◽  
Preclinical Development ◽  
Neonatal Mice ◽  
Mucin Expression ◽  
Lung Epithelial ◽  
The Impact

Recent studies found that expression of Nedd4‑2 is reduced in lung tissue from patients with idiopathic pulmonary fibrosis (IPF) and that the conditional deletion of Nedd4‑2 in lung epithelial cells causes IPF-like disease in adult mice via multiple defects, including dysregulation of the epithelial Na+ channel (ENaC), TGFβ signaling and the biosynthesis of surfactant protein-C proprotein (proSP-C). However, knowledge of the impact of congenital deletion of Nedd4‑2 on the lung phenotype remains limited. In this study, we therefore determined the effects of congenital deletion of Nedd4‑2 in the lung epithelial cells of neonatal doxycycline-induced triple transgenic Nedd4‑2fl/fl/CCSP‑rtTA2S‑M2/LC1 mice, with a focus on clinical phenotype, survival, lung morphology, inflammation markers in BAL, mucin expression, ENaC function and proSP‑C trafficking. We found that the congenital deletion of Nedd4‑2 caused a rapidly progressive lung disease in neonatal mice that shares key features with interstitial lung diseases in children (chILD), including hypoxemia, growth failure, sterile pneumonitis, fibrotic lung remodeling and high mortality. The congenital deletion of Nedd4‑2 in lung epithelial cells caused increased expression of Muc5b and mucus plugging of distal airways, increased ENaC activity and proSP-C mistrafficking. This model of congenital deletion of Nedd4‑2 may support studies of the pathogenesis and preclinical development of therapies for chILD.

scholarly journals Host DNA Repair Proteins in Response toPseudomonas aeruginosain Lung Epithelial Cells and in Mice

2010 ◽  
Vol 79 (1) ◽  
pp. 75-87 ◽  
Author(s):  
Min Wu ◽  
Huang Huang ◽  
Weidong Zhang ◽  
Shibichakravarthy Kannan ◽  
Andrew Weaver ◽  
...  
Keyword(s):  
Dna Damage ◽  
Dna Repair ◽  
Epithelial Cells ◽  
Critical Role ◽  
Lung Epithelial Cells ◽  
Host Cells ◽  
Myeloperoxidase Activity ◽  
Gram Negative ◽  
Lung Epithelial ◽  
Dna Repair Proteins

ABSTRACTAlthough DNA repair proteins in bacteria are critical for pathogens' genome stability and for subverting the host defense, the role of host DNA repair proteins in response to bacterial infection is poorly defined. Here, we demonstrate, for the first time, that infection with the Gram-negative bacteriumPseudomonas aeruginosasignificantly altered the expression and enzymatic activity of 8-oxoguanine DNA glycosylase (OGG1) in lung epithelial cells. Downregulation of OGG1 by a small interfering RNA strategy resulted in severe DNA damage and cell death. In addition, acetylation of OGG1 is required for host responses to bacterial genotoxicity, as mutations of OGG1 acetylation sites increased Cockayne syndrome group B (CSB) protein expression. These results also indicate that CSB may be involved in DNA repair activity during infection. Furthermore, OGG1 knockout mice exhibited increased lung injury after infection withP. aeruginosa, as demonstrated by higher myeloperoxidase activity and lipid peroxidation. Together, our studies indicate thatP. aeruginosainfection induces significant DNA damage in host cells and that DNA repair proteins play a critical role in the host response toP. aeruginosainfection, serving as promising targets for the treatment of this condition and perhaps more broadly Gram-negative bacterial infections.

scholarly journals Cell-surface translocation of annexin A2 contributes to bleomycin-induced pulmonary fibrosis by mediating inflammatory response in mice

2019 ◽  
Vol 133 (7) ◽  
pp. 789-804 ◽  
Author(s):  
Yunlong Lei ◽  
Kui Wang ◽  
Xuefeng Li ◽  
Yi Li ◽  
Xuping Feng ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Inflammatory Response ◽  
Cell Surface ◽  
Annexin A2 ◽  
Lung Epithelial Cells ◽  
Cancer Drug ◽  
Autophagic Flux ◽  
Lung Epithelial ◽  
Surface Translocation

Abstract Bleomycin, a widely used anti-cancer drug, may give rise to pulmonary fibrosis, a serious side effect which is associated with significant morbidity and mortality. Despite the intensive efforts, the precise pathogenic mechanisms of pulmonary fibrosis still remain to be clarified. Our previous study showed that bleomycin bound directly to annexin A2 (ANXA2, or p36), leading to development of pulmonary fibrosis by impeding transcription factor EB (TFEB)-induced autophagic flux. Here, we demonstrated that ANXA2 also played a critical role in bleomycin-induced inflammation, which represents another major cause of bleomycin-induced pulmonary fibrosis. We found that bleomycin could induce the cell surface translocation of ANXA2 in lung epithelial cells through exosomal secretion, associated with enhanced interaction between ANXA2 and p11. Knockdown of ANXA2 or blocking membrane ANXA2 mitigated bleomycin-induced activation of nuclear factor (NF)-κB pathway and production of pro-inflammatory cytokine IL-6 in lung epithelial cells. ANXA2-deficient (ANXA2−/−) mice treated with bleomycin exhibit reduced pulmonary fibrosis along with decreased cytokine production compared with bleomycin-challenged wild-type mice. Further, the surface ANXA2 inhibitor TM601 could ameliorate fibrotic and inflammatory response in bleomycin-treated mice. Taken together, our results indicated that, in addition to disturbing autophagic flux, ANXA2 can contribute to bleomycin-induced pulmonary fibrosis by mediating inflammatory response.

Captopril inhibits apoptosis in human lung epithelial cells: a potential antifibrotic mechanism

1998 ◽  
Vol 275 (5) ◽  
pp. L1013-L1017 ◽  
Author(s):  
Bruce D. Uhal ◽  
Claudia Gidea ◽  
Raed Bargout ◽  
Antonio Bifero ◽  
Olivia Ibarra-Sunga ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Pulmonary Fibrosis ◽  
Dna Fragmentation ◽  
Cell Apoptosis ◽  
Human Lung ◽  
Lung Epithelial Cells ◽  
Lung Epithelial ◽  
Epithelial Cell Apoptosis

The angiotensin-converting enzyme inhibitor captopril has been shown to inhibit fibrogenesis in the lung, but the mechanisms underlying this action are unclear. Apoptosis of lung epithelial cells is believed to be involved in the pathogenesis of pulmonary fibrosis. For these reasons, we studied the effect of captopril on Fas-induced apoptosis in a human lung epithelial cell line. Monoclonal antibodies that activate the Fas receptor induced epithelial cell apoptosis as detected by chromatin condensation, nuclear fragmentation, DNA fragmentation, and increased activities of caspase-1 and -3. Apoptosis was not induced by isotype-matched nonimmune mouse immunoglobulins or nonactivating anti-Fas monoclonal antibodies. When applied simultaneously with anti-Fas antibodies, 50 ng/ml of captopril completely abrogated apoptotic indexes based on morphology, DNA fragmentation, and inducible caspase-1 activity and significantly decreased the inducible activity of caspase-3. Inhibition of apoptosis by captopril was concentration dependent, with an IC50 of 70 pg/ml. These data suggest that the inhibitory actions of captopril on pulmonary fibrosis may be related to prevention of lung epithelial cell apoptosis.

scholarly journals Regulation of apoptosis by Bcl-2 cysteine oxidation in human lung epithelial cells

2013 ◽  
Vol 24 (6) ◽  
pp. 858-869 ◽  
Author(s):  
Sudjit Luanpitpong ◽  
Pithi Chanvorachote ◽  
Christian Stehlik ◽  
William Tse ◽  
Patrick S. Callery ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Epithelial Cells ◽  
Human Lung ◽  
Critical Role ◽  
B Cell Lymphoma ◽  
Lung Epithelial Cells ◽  
Mitogen Activated Protein Kinase ◽  
Cysteine Oxidation ◽  
Lung Epithelial ◽  
Human Lung Epithelial Cells

Hydrogen peroxide is a key mediator of oxidative stress known to be important in various cellular processes, including apoptosis. B-cell lymphoma-2 (Bcl-2) is an oxidative stress–responsive protein and a key regulator of apoptosis; however, the underlying mechanisms of oxidative regulation of Bcl-2 are not well understood. The present study investigates the direct effect of H2O2on Bcl-2 cysteine oxidation as a potential mechanism of apoptosis regulation. Exposure of human lung epithelial cells to H2O2induces apoptosis concomitant with cysteine oxidation and down-regulation of Bcl-2. Inhibition of Bcl-2 oxidation by antioxidants or by site-directed mutagenesis of Bcl-2 at Cys-158 and Cys-229 abrogates the effects of H2O2on Bcl-2 and apoptosis. Immunoprecipitation and confocal microscopic studies show that Bcl-2 interacts with mitogen-activated protein kinase (extracellular signal-regulated kinase 1/2 [ERK1/2]) to suppress apoptosis and that this interaction is modulated by cysteine oxidation of Bcl-2. The H2O2-induced Bcl-2 cysteine oxidation interferes with Bcl-2 and ERK1/2 interaction. Mutation of the cysteine residues inhibits the disruption of Bcl-2–ERK complex, as well as the induction of apoptosis by H2O2. Taken together, these results demonstrate the critical role of Bcl-2 cysteine oxidation in the regulation of apoptosis through ERK signaling. This new finding reveals crucial redox regulatory mechanisms that control the antiapoptotic function of Bcl-2.

scholarly journals Prostasin regulates epithelial monolayer function: cell-specific Gpld1-mediated secretion and functional role for GPI anchor

2006 ◽  
Vol 291 (6) ◽  
pp. C1258-C1270 ◽  
Author(s):  
George M. Verghese ◽  
Michael F. Gutknecht ◽  
George H. Caughey
Keyword(s):  
Epithelial Cells ◽  
Cell Surface ◽  
Collecting Duct ◽  
Critical Role ◽  
Lung Epithelial Cells ◽  
Peptidase Activity ◽  
Apical Surface ◽  
Gpi Anchor ◽  
Epithelial Monolayer ◽  
Lung Epithelial

Prostasin, a trypsinlike serine peptidase, is highly expressed in prostate, kidney, and lung epithelia, where it is bound to the cell surface, secreted, or both. Prostasin activates the epithelial sodium channel (ENaC) and suppresses invasion of prostate and breast cancer cells. The studies reported here establish mechanisms of membrane anchoring and secretion in kidney and lung epithelial cells and demonstrate a critical role for prostasin in regulating epithelial monolayer function. We report that endogenous mouse prostasin is glycosylphosphatidylinositol (GPI) anchored to the cell surface and is constitutively secreted from the apical surface of kidney cortical collecting duct cells. Using site-directed mutagenesis, detergent phase separation, and RNA interference approaches, we show that prostasin secretion depends on GPI anchor cleavage by endogenous GPI-specific phospholipase D1 (Gpld1). Secretion of prostasin by kidney and lung epithelial cells, in contrast to prostate epithelium, does not depend on COOH-terminal processing at conserved Arg322. Using stably transfected M-1 cells expressing wild-type, catalytically inactive, or chimeric transmembrane (not GPI)-anchored prostasins we establish that prostasin regulates transepithelial resistance, current, and paracellular permeability by GPI anchor- and protease activity-dependent mechanisms. These studies demonstrate a novel role for prostasin in regulating epithelial monolayer resistance and permeability in kidney epithelial cells and, furthermore, show specifically that prostasin is a critical regulator of transepithelial ion transport in M-1 cells. These functions depend on the GPI anchor as well as the peptidase activity of prostasin. These studies suggest that cell-specific Gpld1- or peptidase-dependent pathways for prostasin secretion may control prostasin functions in a tissue-specific manner.

Mitochondrial localization of catalase provides optimal protection from H2O2-induced cell death in lung epithelial cells

2006 ◽  
Vol 290 (5) ◽  
pp. L978-L986 ◽  
Author(s):  
Yuko Arita ◽  
S. Hella Harkness ◽  
Jeffrey A. Kazzaz ◽  
Hshi-chi Koo ◽  
Ansamma Joseph ◽  
...  
Keyword(s):  
Cell Death ◽  
Epithelial Cells ◽  
Cell Survival ◽  
Cell Lines ◽  
Mitochondrial Function ◽  
Critical Role ◽  
Lung Epithelial Cells ◽  
Mitochondrial Localization ◽  
Stable Cell Lines ◽  
Lung Epithelial

Reactive oxygen species (ROS) can cause cell injury and death via mitochondrial-dependent pathways, and supplementation with antioxidants has been shown to ameliorate these processes. The c-Jun NH2-terminal kinase (JNK) pathway has been shown to play a critical role in ROS-induced cell death. To determine if targeting catalase (CAT) to the mitochondria provides better protection than cytosolic expression against H2O2-induced injury, the following two approaches were taken: 1) adenoviral-mediated transduction was performed using cytosolic (CCAT) or mitochondrial (MCAT) CAT cDNAs and 2) stable cell lines were generated overexpressing CAT in mitochondria ( n = 3). Cells were exposed to 250 μM H2O2, and cell survival, mitochondrial function, cytochrome c release, and JNK activity were analyzed. Although all viral transduced cells had a transient twofold increase in CAT activity, MCAT cells had significantly higher survival rates, the best mitochondrial function, and lowest JNK activity compared with CCAT and LacZ controls. The improved protection with MCAT was observed in primary type II lung epithelial cells and in transformed lung epithelial cells. In the three stable cell lines, cell survival directly correlated with extent of mitochondrial localization ( r = 0.60572, P < 0.05) and not overall CAT activity ( r = −0.45501, P < 0.05). Data indicate that targeting of antioxidants directly to the mitochondria is more effective in protecting lung epithelial cells against ROS-induced injury. This has important implications in antioxidant supplementation trials to prevent ROS-induced lung injury in critically ill patients.

scholarly journals Targeted epigenetic editing of SPDEF reduces mucus production in lung epithelial cells

2017 ◽  
Vol 312 (3) ◽  
pp. L334-L347 ◽  
Author(s):  
Juan Song ◽  
David Cano-Rodriquez ◽  
Melanie Winkle ◽  
Rutger A. F. Gjaltema ◽  
Désirée Goubert ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Critical Role ◽  
Dna Methyltransferases ◽  
Lung Epithelial Cells ◽  
The Novel ◽  
Mucus Production ◽  
Lung Epithelial ◽  
Mrna And Protein Expression ◽  
Novel Strategy ◽  
Epigenetic Editing

Airway mucus hypersecretion contributes to the morbidity and mortality in patients with chronic inflammatory lung diseases. Reducing mucus production is crucial for improving patients’ quality of life. The transcription factor SAM-pointed domain–containing Ets-like factor ( SPDEF) plays a critical role in the regulation of mucus production and, therefore, represents a potential therapeutic target. This study aims to reduce lung epithelial mucus production by targeted silencing SPDEF using the novel strategy, epigenetic editing. Zinc fingers and CRISPR/dCas platforms were engineered to target repressors (KRAB, DNA methyltransferases, histone methyltransferases) to the SPDEF promoter. All constructs were able to effectively suppress both SPDEF mRNA and protein expression, which was accompanied by inhibition of downstream mucus-related genes [anterior gradient 2 ( AGR2), mucin 5AC ( MUC5AC)]. For the histone methyltransferase G9A, and not its mutant or other effectors, the obtained silencing was mitotically stable. These results indicate efficient SPDEF silencing and downregulation of mucus-related gene expression by epigenetic editing, in human lung epithelial cells. This opens avenues for epigenetic editing as a novel therapeutic strategy to induce long-lasting mucus inhibition.

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