Cell tracing reveals the transdifferentiation fate of mouse lung epithelial cells during pulmonary fibrosis in vivo

AbstractAccumulation of senescent cells contributes to age related diseases including idiopathic pulmonary fibrosis (IPF). Insulin-like growth factor binding proteins (IGFBPs) are evolutionarily conserved proteins that play a vital role in many biological processes. Overall, little is known about the functions of IGFBP2 in the epigenetic regulation of cellular senescence and pulmonary fibrosis. Here, we show that Igfbp2 expression was significantly downregulated at both mRNA and protein levels in a low-dose bleomycin-induced pulmonary fibrosis model of aged mice. Using the reduced representation of bisulfite sequencing technique, we demonstrated Igfbp2 downregulation is attributed to DNA methylation of CpG islands in fibrotic lungs of aged mice. Furthermore, Igfbp2 siRNA knockdown increased both P53 and P21 protein levels in mouse lung epithelial cells exposed to hypoxia treatment. Lentiviral mediated expression of Igfb2 decreased P21 protein levels and significantly reduced beta galactosidase activity in mouse lung epithelial cells challenged with a senescent drug (atazanavir) and hypoxia treatments. Using the RT2 Profiler PCR Array, we found that P21, PAI-1, IRF-5 and IRF-7, important regulators of senescence pathway, were significantly downregulated specifically in type-II alveolar epithelial cells (AECs) of aged human-Igfbp2 transgenic mice after bleomycin challenge. Finally, transgenic expression of human-Igfbp2 in type-II AECs from aged bleomycin challenged mice significantly decreased senescent associated secretory phenotype factors and also reduced extracellular matrix markers compared to aged wild-type mice challenged with bleomycin injury. Collectively, these findings reveal that epigenetic repression of Igfbp2 promotes pulmonary fibrosis and that restoring IGFBP2 in fibrotic lungs could prove effective in IPF treatment.

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Regulation of IL-33 by Oncostatin M in Mouse Lung Epithelial Cells

Mediators of Inflammation ◽

10.1155/2016/9858374 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 8

Author(s):

Carl D. Richards ◽

Laura Izakelian ◽

Anisha Dubey ◽

Grace Zhang ◽

Steven Wong ◽

...

Keyword(s):

Epithelial Cells ◽

Alveolar Epithelial Cells ◽

Lung Epithelial Cells ◽

Oncostatin M ◽

Mouse Lung ◽

Nuclear Staining ◽

Potent Inducer ◽

Alveolar Epithelial ◽

Lung Epithelial

IL-33 modulates both innate and adaptive immune responses at tissue sites including lung and may play critical roles in inflammatory lung disease. Although IL-33 expression can be altered upon NF-Kappa B activation, here we examine regulation by Oncostatin M, a gp130 cytokine family member, in mouse lung tissue. Responses were assessed in BALB/c mouse lung at day 7 of transient overexpression using endotracheally administered adenovirus encoding OSM (AdOSM) or empty vector (AdDel70). Whole lung extracts showed induction of IL-33 mRNA (>20-fold) and protein (10-fold increase in immunoblots) by AdOSM relative to AdDel70. Immunohistochemistry for IL-33 indicated a marked induction of nuclear staining in alveolar epithelial cellsin vivo. Oncostatin M stimulated IL-33 mRNA and IL-33 full length protein in C10 mouse type 2 alveolar epithelial cells in culture in time-dependent and dose-dependent fashion, whereas IL-6, LIF, IL-31, IL-4, or IL-13 did not, and TGFβrepressed IL-33. IL-33 induction was associated with activation of STAT3, and pharmacological inhibition of STAT3 ameliorated IL-33 levels. These results indicate Oncostatin M as a potent inducer of IL-33 in mouse lung epithelial cells and suggest that an OSM/IL-33 axis may participate in innate immunity and inflammatory conditions in lung.

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Bleomycin initiates apoptosis of lung epithelial cells by ROS but not by Fas/FasL pathway

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00300.2004 ◽

2006 ◽

Vol 290 (4) ◽

pp. L790-L796 ◽

Cited By ~ 127

Author(s):

Shulamit B. Wallach-Dayan ◽

Gabriel Izbicki ◽

Pazit Y. Cohen ◽

Regina Gerstl-Golan ◽

Alan Fine ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Lung Epithelial Cells ◽

Mouse Lung ◽

Caspase 8 ◽

Caspase 9 ◽

Lung Epithelial ◽

Induced Apoptosis

Epithelial cells are considered to be a main target of bleomycin-induced lung injury, which leads to fibrosis in vivo. We studied the characteristics of in vitro bleomycin-induced apoptosis in a mouse lung epithelial (MLE) cell line. Bleomycin caused an increase of reactive oxygen species (ROS) resulting in oxidative stress, mitochondrial leakage, and apoptosis. These were associated with elevated caspase-8 and resultant caspase-9 activity and with upregulation of Fas expression. Glutathione and inhibitors of caspase-8 or caspase-9, but not of FasL, inhibited these effects, suggesting their dependence on ROS, caspase-8 and -9, in a Fas/FasL-independent pathway. However, postbleomycin-exposed MLE cells were more sensitive to Fas-mediated apoptosis. These results demonstrate that the initial bleomycin-induced oxidative stress causes a direct apoptotic effect in lung epithelial cells involving a regulatory role of caspase-8 on caspase-9. Fas represents an amplification mechanism, and not a direct trigger of bleomycin-induced epithelial cell apoptosis.

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Effect of Slit/Robo signaling on regeneration in lung emphysema

Experimental & Molecular Medicine ◽

10.1038/s12276-021-00633-8 ◽

2021 ◽

Author(s):

Jin-Soo Park ◽

RyeonJin Cho ◽

Eun-Young Kang ◽

Yeon-Mok Oh

Keyword(s):

Epithelial Cells ◽

Mouse Model ◽

Lung Epithelial Cells ◽

Mouse Lung ◽

Chronic Obstructive ◽

Irreversible Damage ◽

Lung Epithelial ◽

And Migration ◽

Proliferation And Migration

AbstractEmphysema, a pathological component of chronic obstructive pulmonary disease, causes irreversible damage to the lung. Previous studies have shown that Slit plays essential roles in cell proliferation, angiogenesis, and organ development. In this study, we evaluated the effect of Slit2 on the proliferation and migration of mouse lung epithelial cells and its role in regeneration in an emphysema lung mouse model. Here, we have shown that Slit2/Robo signaling contributes to the regeneration of lungs damaged by emphysema. Mouse epithelial lung cells treated with Slit2 exhibited increased proliferation and migration in vitro. Our results also showed that Slit2 administration improved alveolar regeneration in the emphysema mouse model in vivo. Furthermore, Slit2/Robo signaling increased the phosphorylation of ERK and Akt, which was mediated by Ras activity. These Slit2-mediated cellular signaling processes may be involved in the proliferation and migration of mouse lung epithelial cells and are also associated with the potential mechanism of lung regeneration. Our findings suggest that Slit2 administration may be beneficial for alveolar regeneration in lungs damaged by emphysema.

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

International Journal of Molecular Sciences ◽

10.3390/ijms22116146 ◽

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.

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In Vivo and In Vitro Analysis of Factor Binding Sites in Jaagsiekte Sheep Retrovirus Long Terminal Repeat Enhancer Sequences: Roles of HNF-3, NF-I, and C/EBP for Activity in Lung Epithelial Cells

Journal of Virology ◽

10.1128/jvi.80.1.332-341.2006 ◽

2006 ◽

Vol 80 (1) ◽

pp. 332-341 ◽

Cited By ~ 20

Author(s):

Kathleen McGee-Estrada ◽

Hung Fan

Keyword(s):

Epithelial Cells ◽

Long Terminal Repeat ◽

Binding Site ◽

Terminal Repeat ◽

Lung Epithelial Cells ◽

Type Ii ◽

Jaagsiekte Sheep Retrovirus ◽

Efficient System ◽

Lung Epithelial

ABSTRACT Jaagsiekte sheep retrovirus (JSRV) is the causative agent of ovine pulmonary adenocarcinoma, a contagious lung cancer of sheep that arises from type II pneumocytes and Clara cells of the lung epithelium. Studies of the tropism of this virus have been hindered by the lack of an efficient system for viral replication in tissue culture. To map regulatory regions important for transcriptional activation, an in vivo footprinting method that couples dimethyl sulfate treatment and ligation-mediated PCR was performed in murine type II pneumocyte-derived MLE-15 cells infected with a chimeric Moloney murine leukemia virus driven by the JSRV enhancers (ΔMo+JS Mo-MuLV). In vivo footprints were found in the JSRV enhancers in two regions previously shown to be important for JSRV long terminal repeat (LTR) activity: a binding site for the lung-specific transcription factor HNF-3β and an E-box element in the distal enhancer adjacent to an NF-κB-like binding site. In addition, in vivo footprints were detected in two downstream motifs likely to bind C/EBP and NF-I. Mutational analysis of a JSRV LTR reporter construct (pJS21luc) revealed that the C/EBP binding site is critical for LTR activity, while the putative NF-I binding element is less important; elimination of these sites resulted in 70% and 40% drops in LTR activity, respectively. Electrophoretic mobility shift assays using nuclear extracts from MLE-15 murine Clara cell-derived mtCC1-2 cells with probes corresponding to the NF-I or C/EBP sites revealed several complexes. Antiserum directed against NF-IA, C/EBPα, or C/EBPβ supershifted the corresponding protein-DNA complexes, indicating that these isoforms, which are also important for the expression of several cellular lung-specific genes, may be important for JSRV expression in lung epithelial cells.

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All-trans retinoic acid increases expression of aquaporin-5 and plasma membrane water permeability via transactivation of Sp1 in mouse lung epithelial cells

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2006.10.159 ◽

2006 ◽

Vol 351 (4) ◽

pp. 1048-1053 ◽

Cited By ~ 17

Author(s):

Johji Nomura ◽

Ichiro Horie ◽

Mayumi Seto ◽

Kazufumi Nagai ◽

Akinori Hisatsune ◽

...

Keyword(s):

Plasma Membrane ◽

Retinoic Acid ◽

Epithelial Cells ◽

Water Permeability ◽

Lung Epithelial Cells ◽

Mouse Lung ◽

Aquaporin 5 ◽

Trans Retinoic Acid ◽

All Trans Retinoic Acid ◽

Lung Epithelial

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EphB6 Regulates TFEB-Lysosomal Pathway and Survival of Disseminated Indolent Breast Cancer Cells

Cancers ◽

10.3390/cancers13051079 ◽

2021 ◽

Vol 13 (5) ◽

pp. 1079

Author(s):

Manuela Zangrossi ◽

Patrizia Romani ◽

Probir Chakravarty ◽

Colin D.H. Ratcliffe ◽

Steven Hooper ◽

...

Keyword(s):

Breast Cancer ◽

Epithelial Cells ◽

Cancer Cells ◽

Lung Epithelial Cells ◽

Late Relapse ◽

Alveolar Type ◽

Type I ◽

Extrinsic Factors ◽

Lung Epithelial

Late relapse of disseminated cancer cells is a common feature of breast and prostate tumors. Several intrinsic and extrinsic factors have been shown to affect quiescence and reawakening of disseminated dormant cancer cells (DDCCs); however, the signals and processes sustaining the survival of DDCCs in a foreign environment are still poorly understood. We have recently shown that crosstalk with lung epithelial cells promotes survival of DDCCs of estrogen receptor-positive (ER+) breast tumors. By using a lung organotypic system and in vivo dissemination assays, here we show that the TFEB-lysosomal axis is activated in DDCCs and that it is modulated by the pro-survival ephrin receptor EphB6. TFEB lysosomal direct targets are enriched in DDCCs in vivo and correlate with relapse in ER+ breast cancer patients. Direct coculture of DDCCs with alveolar type I-like lung epithelial cells and dissemination in the lung drive lysosomal accumulation and EphB6 induction. EphB6 contributes to survival, TFEB transcriptional activity, and lysosome formation in DDCCs in vitro and in vivo. Furthermore, signaling from EphB6 promotes the proliferation of surrounding lung parenchymal cells in vivo. Our data provide evidence that EphB6 is a key factor in the crosstalk between disseminated dormant cancer cells and the lung parenchyma and that the TFEB-lysosomal pathway plays an important role in the persistence of DDCCs.

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