scholarly journals An Antisense Oligonucleotide to 1-cys Peroxiredoxin Causes Lipid Peroxidation and Apoptosis in Lung Epithelial Cells

2002 ◽  
Vol 277 (51) ◽  
pp. 49927-49934 ◽  
Author(s):  
Jhang Ho Pak ◽  
Yefim Manevich ◽  
Han Suk Kim ◽  
Sheldon I. Feinstein ◽  
Aron B. Fisher
Keyword(s):  
Lipid Peroxidation ◽  
Antisense Oligonucleotide ◽  
Plasma Membranes ◽  
Apoptotic Cell ◽  
Lung Epithelial Cells ◽  
Epithelial Cell Line ◽  
Positive Staining ◽  
Complementary Sequence ◽  
Lung Epithelial ◽  
And Control

1-cys peroxiredoxin (1-cysPrx), a member of the peroxiredoxin superfamily, reduces phospholipid hydroperoxides as well as organic peroxides and H2O2. To determine the physiological function(s) of 1-cysPrx, we have used an antisense strategy to suppress endogenous 1-cysPrx in L2 cells, a rat lung epithelial cell line. A 25-base antisense morpholino oligonucleotide was designed to bind a complementary sequence overlapping the translational start site (−18 to +7) in the rat 1-cysPrx mRNA, blocking protein synthesis. Treatment with an antisense oligonucleotide for 48 h resulted in approximately 60% suppression of the 1-cysPrx protein content as measured by immunoblot analysis and an approximately 44% decrease of glutathione peroxidase activity as compared with random oligonucleotide treated and control (vehicle only) cells. Accumulation of phosphatidylcholine hydroperoxide in plasma membranes was demonstrated by high pressure liquid chromatography assay for conjugated dienes (260 pmol/106cells for antisenseversus70 pmol/106cells for random oligonucleotide and control cells) and by fluorescence of diphenyl-1-pyrenylphosphine, a probe for lipid peroxidation. The percentage of cells showing positive staining for annexin V and propidium iodide after antisense treatment was 40% at 28 h and 80% at 48 h. TdT-mediated dUTP nick end labeling assay at 48 h indicated DNA fragmentation in antisense-treated cells that was blocked by prior infection with adenovirus encoding 1-cysPrx or by pretreatment with a vitamin E analogue. The results indicate that 1-cysPrx can function in the intact cell as an antioxidant enzyme to reduce the accumulation of phospholipid hydroperoxides and prevent apoptotic cell death.

The lack of attachment of transformed embryonic lung epithelial cells to collagen I is corrected by fibronectin and FXIII

1986 ◽  
Vol 86 (1) ◽  
pp. 95-107
Author(s):  
M. Paye ◽  
C.M. Lapiere
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Line ◽  
Lung Epithelial Cells ◽  
Collagen I ◽  
Epithelial Cell Line ◽  
Embryonic Lung ◽  
Lung Epithelial ◽  
Minimal Concentration ◽  
Pulmonary Epithelial Cell

PER cells, a transformed pulmonary epithelial cell line that adhered to a large extent to a fibronectin substratum, were found to be attachment-deficient to collagen I. Although fibronectin can bind to collagen I monomers and polymers, the addition of exogenous fibronectin in the attachment medium induced the adhesion of these cells to collagen I polymers but not to monomers. By adding the transglutaminase of blood coagulation, FXIII, in the presence of fibronectin, the attachment of PER cells to collagen I monomers could be recovered while the minimal concentration of fibronectin needed to promote their adhesion to polymers was lowered. These studies indicate that FXIII enhances the fibronectin-mediated attachment of PER cells to collagen I.

Pneumococci induced TLR- and Rac1-dependent NF-κB-recruitment to the IL-8 promoter in lung epithelial cells

2006 ◽  
Vol 290 (4) ◽  
pp. L730-L737 ◽  
Author(s):  
Bernd Schmeck ◽  
Sylvia Huber ◽  
Kerstin Moog ◽  
Janine Zahlten ◽  
Andreas C. Hocke ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Cell Activation ◽  
Rho Gtpase ◽  
Dominant Negative ◽  
Lung Epithelial Cells ◽  
Dominant Negative Mutant ◽  
Epithelial Cell Line ◽  
Phosphatidylinositol 3 Kinase ◽  
Lung Epithelial ◽  
Phosphatidylinositol 3

Streptococcus pneumoniae is the major pathogen of community-acquired pneumonia. The respiratory epithelium constitutes the first line of defense against invading lung pathogens, including pneumococci. We analyzed the involvement of Toll-like receptors (TLR) and Rho-GTPase signaling in the activation of human lung epithelial cells by pneumococci. S. pneumoniae induced release of interleukin-8 (IL-8) by human bronchial epithelial cell line BEAS-2B. Specific inhibition of Rac1 by Nsc23766 or a dominant-negative mutant of Rac1 strongly reduced cytokine release. In addition, pneumococci-related cell activation (IL-8 release, NF-κB-activation) depended on MyD88, phosphatidylinositol 3-kinase, and Cdc42 but not on RhoA. Pneumococci enhanced TLR1 and TLR2 mRNA expression in BEAS-2B cells, whereas TLR4 and TLR6 expression was constitutively high. TLR1 and 2 synergistically recognized pneumococci in cotransfection experiments. TLR4, TLR6, LPS-binding protein, and CD14 seem not to be involved in pneumococci-dependent cell activation. At the IL-8 gene promoter, recruitment of phosphorylated NF-κB subunit p65 was blocked by inhibition of Rac1, whereas binding of the phosphorylated activator protein-1 subunit c-Jun to the promoter was not diminished. In summary, these results suggest that S. pneumoniae activate human epithelial cells by TLR1/2 and a phosphatidylinositol 3-kinase- and Rac1-dependent NF-κB-recruitment to the IL-8 promoter.

scholarly journals Glycyrrhizin suppresses epithelial-mesenchymal transition by inhibiting high-mobility group box1 via the TGF-β1/Smad2/3 pathway in lung epithelial cells

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8514 ◽  
Author(s):  
Yanni Gui ◽  
Jian Sun ◽  
Wenjie You ◽  
Yuanhui Wei ◽  
Han Tian ◽  
...  
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Cell Line ◽  
Epithelial Mesenchymal Transition ◽  
High Mobility ◽  
Lung Epithelial Cells ◽  
Epithelial Cell Line ◽  
Mesenchymal Transition ◽  
Lung Epithelial ◽  
Hmgb1 Expression

Background Epithelial-mesenchymal transition (EMT) plays an important role in fibrosis, chronic inflammation, tumor metastasis, etc. Glycyrrhizin, an active component extracted from licorice plant, has been reported to treat a variety of inflammatory reactions through inhibiting high-mobility group box1 (HMGB1), which has been suggested to be a significant mediator in EMT process. However, whether glycyrrhizin affects the EMT process or not remains unclear. Methods Human alveolar epithelial cell line A549 and normal human bronchial epithelial cell line BEAS-2B were treated with extrinsic TGF-β1 to induce EMT. Elisa was used to detect HMGB1 concentrations in cell supernatant. RNA interference and lentivirus infection experiments were performed to investigate the involvement of HMGB1 in EMT process. Cell Counting Kit-8 (CCK-8) was used to detect the viability of A549 and BEAS-2B cells treated with glycyrrhizin. Finally, the effects of glycyrrhizin on EMT changes, as well as the underlying mechanisms, were evaluated via Western blot, immunofluorescence and transwell assays. Results Our results showed that HMGB1 expression was increased by TGF-β1, and knockdown of HMGB1 expression reversed TGF-β1-induced EMT in A549 and BEAS-2B cells. Ectopic HMGB1 expression or TGF-β1 treatment caused a significant increase in HMGB1 release. Notably, we found that glycyrrhizin treatment effectively suppressed TGF-β1-induced EMT process by inhibiting HMGB1. Also, glycyrrhizin significantly inhibited the migration of both A549 and BEAS-2B cells promoted by TGF-β1. Mechanistically, HMGB1 overexpression could activate Smad2/3 signaling in A549 and BEAS-2B cells. Glycyrrhizin significantly blocked the phosphorylation of Smad2/3 stimulated either by TGF-β1 or by ectopic HMGB1 in A549 and BEAS-2B cells. Conclusions HMGB1 is a vital mediator of EMT changes induced by TGF-β1 in lung epithelial cells. Importantly, glycyrrhizin can effectively block Smad2/3 signaling pathway through inhibiting HMGB1, thereby suppressing the EMT progress.

Bioassay of a tracheal smooth muscle-constricting factor released by respiratory epithelial cells

1992 ◽  
Vol 263 (1) ◽  
pp. L137-L141 ◽  
Author(s):  
J. H. Wilkens ◽  
A. Becker ◽  
H. Wilkens ◽  
M. Emura ◽  
M. Riebe-Imre ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Epithelial Cell ◽  
Epithelial Cells ◽  
Muscle Tone ◽  
Lung Epithelial Cells ◽  
Epithelial Cell Line ◽  
Cell Column ◽  
Respiratory Epithelial Cells ◽  
Lung Epithelial ◽  
Respiratory Epithelial

Epithelium-derived factors of unknown identity have been proposed to modulate airway smooth muscle tone. We developed a novel sensitive bioassay system that allows serial perfusion of cultured respiratory epithelial cells and guinea pig trachea (GPT). GPT responses were assessed as diameter changes by computerized video microscopy (resolution, 15 microns). A permanent hamster lung epithelial cell line was grown on microcarrier beads and perfused in a cell column. When the outflow tubing from the epithelial cell column was connected to the inflow cannula, the detector GPT contracted, reaching 28 +/- 6% of the maximum methacholine (100 microM)-induced contraction (n = 12, P less than 0.001). Perfusion of the cell column with diclofenac (10 microM) or lysin-mono-acetylsalicylic acid (100 microM) abolished the GPT contraction, whereas selective perfusion of the detector GPT with either agent did not block the contraction. Analysis of the effluent of the epithelial cell column demonstrated a significant basal release of prostaglandins F2 alpha and E2 (PGF2 alpha and PGE2) and 6-ketoprostaglandin F1 alpha, whereas only marginal amounts of thromboxane B2 were detected. When given exogenously, PGF2 alpha, PGE2, PGI2, and U-46619 all contracted the GPT. It is concluded that lung epithelial cells can contract GPT by releasing a transferable factor. This factor is likely to be a constrictor cyclooxygenase product that is not produced in epithelium-denuded GPT.

scholarly journals SARS-CoV proteins decrease levels and activity of human ENaC via activation of distinct PKC isoforms

2009 ◽  
Vol 296 (3) ◽  
pp. L372-L383 ◽  
Author(s):  
Hong-Long Ji ◽  
Weifeng Song ◽  
Zhiqian Gao ◽  
Xue-Feng Su ◽  
Hong-Guang Nie ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Plasma Membranes ◽  
Lung Epithelial Cells ◽  
Cell Surface Expression ◽  
Atypical Pneumonia ◽  
E Proteins ◽  
Whole Cell ◽  
Acute Lung Failure ◽  
E Protein ◽  
Lung Epithelial

Among the multiple organ disorders caused by the severe acute respiratory syndrome coronavirus (SARS-CoV), acute lung failure following atypical pneumonia is the most serious and often fatal event. We hypothesized that two of the hydrophilic structural coronoviral proteins (S and E) would regulate alveolar fluid clearance by decreasing the cell surface expression and activity of amiloride-sensitive epithelial sodium (Na+) channels (ENaC), the rate-limiting protein in transepithelial Na+ vectorial transport across distal lung epithelial cells. Coexpression of either S or E protein with human α-, β-, and γ-ENaC in Xenopus oocytes led to significant decreases of both amiloride-sensitive Na+ currents and γ-ENaC protein levels at their plasma membranes. S and E proteins decreased the rate of ENaC exocytosis and either had no effect (S) or decreased (E) rates of endocytosis. No direct interactions among SARS-CoV E protein with either α- or γ-ENaC were indentified. Instead, the downregulation of ENaC activity by SARS proteins was partially or completely restored by administration of inhibitors of PKCα/β1 and PKCζ. Consistent with the whole cell data, expression of S and E proteins decreased ENaC single-channel activity in oocytes, and these effects were partially abrogated by PKCα/β1 inhibitors. Finally, transfection of human airway epithelial (H441) cells with SARS E protein decreased whole cell amiloride-sensitive currents. These findings indicate that lung edema in SARS infection may be due at least in part to activation of PKC by SARS proteins, leading to decreasing levels and activity of ENaC at the apical surfaces of lung epithelial cells.

Paraquat-Induced Apoptotic Cell Death in Lung Epithelial Cells

2006 ◽  
Vol 61 (4) ◽  
pp. 366 ◽  
Author(s):  
Tak Ho Song ◽  
Joo Yeon Yang ◽  
In Kook Jeong ◽  
Jae Seok Park ◽  
Young Koo Jee ◽  
...  
Keyword(s):  
Cell Death ◽  
Epithelial Cells ◽  
Apoptotic Cell ◽  
Apoptotic Cell Death ◽  
Lung Epithelial Cells ◽  
Lung Epithelial

PAR-2 activation and LPS synergistically enhance inflammatory signaling in airway epithelial cells by raising PAR expression level and interleukin-8 release

2007 ◽  
Vol 293 (5) ◽  
pp. L1208-L1218 ◽  
Author(s):  
Ewa Ostrowska ◽  
Elena Sokolova ◽  
Georg Reiser
Keyword(s):  
Epithelial Cell ◽  
Epithelial Cells ◽  
Airway Epithelial Cells ◽  
Lung Epithelial Cells ◽  
Expression Level ◽  
Epithelial Cell Line ◽  
Airway Epithelial ◽  
Protease Activated Receptors ◽  
Lung Epithelial ◽  
Epithelial Cell Lines

Protease-activated receptors (PARs) are involved in the contribution of airway epithelial cells to the development of inflammation by release of pro- and anti-inflammatory mediators. Here, we evaluated in epithelial cells the influence of LPS and continuous PAR activation on PAR expression level and the release of the proinflammatory chemokine IL-8. We studied primary human small airway epithelial cells and two airway epithelial cell lines, A549 and HBE cells. LPS specifically upregulated expression of PAR-2 but not of PAR-1. Exposure of epithelial cells to PAR-1 or PAR-2 agonists increased the PAR-1 expression level. The PAR-2 agonist exhibited higher potency than PAR-1 activators. However, the combined exposure of epithelial cells to LPS and PAR agonists abrogated the PAR-1 upregulation. The PAR-2 expression level was also upregulated after exposure to PAR-1 or PAR-2 agonists. This elevation was higher than the effect of PAR agonists on the PAR-1 level. In contrast to the PAR-1 level, the PAR-2 level remained elevated under concomitant stimulation with LPS and PAR-2 agonist. Furthermore, activation of PAR-2, but not of PAR-1, caused production of IL-8 from the epithelial cells. Interestingly, both in the epithelial cell line and in primary epithelial cells, there was a potentiation of the stimulation of the IL-8 synthesis and release by PAR-2 agonist together with LPS. In summary, these results underline the important role of PAR-2 in human lung epithelial cells. Moreover, our study shows an intricate interplay between LPS and PAR agonists in affecting PAR regulation and IL-8 production.

scholarly journals Effect of Nanoparticles and Environmental Particles on a Cocultures Model of the Air-Blood Barrier

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Rossella Bengalli ◽  
Paride Mantecca ◽  
Marina Camatini ◽  
Maurizio Gualtieri
Keyword(s):  
Endothelial Cells ◽  
Engineered Nanoparticles ◽  
Lung Epithelial Cells ◽  
Epithelial Cell Line ◽  
Alveolar Cells ◽  
Primary Interest ◽  
Ambient Particles ◽  
Inhaled Particles ◽  
Lung Epithelial

Exposure to engineered nanoparticles (NPs) and to ambient particles (PM) has increased significantly. During the last decades the application of nano-objects to daily-life goods and the emissions produced in highly urbanized cities have considerably augmented. As a consequence, the understanding of the possible effects of NPs and PM on human respiratory system and particularly on the air-blood barrier (ABB) has become of primary interest. The crosstalk between lung epithelial cells and underlying endothelial cells is indeed essential in determining the effects of inhaled particles. Here we report the effects of metal oxides NPs (CuO and TiO2) and of PM on anin vitromodel of the ABB constituted by the type II epithelial cell line (NCI-H441) and the endothelial one (HPMEC-ST1.6R). The results demonstrate that apical exposure of alveolar cells induces significant modulation of proinflammatory proteins also in endothelial cells.

15-Lipoxygenase-1 induces expression and release of chemokines in cultured human lung epithelial cells

2009 ◽  
Vol 297 (1) ◽  
pp. L196-L203 ◽  
Author(s):  
Cheng Liu ◽  
Dawei Xu ◽  
Li Liu ◽  
Frida Schain ◽  
Åsa Brunnström ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Human Lung ◽  
A549 Cells ◽  
Airway Epithelial Cells ◽  
Bronchial Epithelial Cells ◽  
Lung Epithelial Cells ◽  
Epithelial Cell Line ◽  
Chronic Obstructive ◽  
Bronchial Epithelial ◽  
Lung Epithelial

15-Lipoxygenase-1 (15-LOX-1) has been proposed to be involved in various physiological and pathophysiological activities such as inflammation, atherosclerosis, cell maturation, and tumorigenesis. Asthma and chronic obstructive pulmonary disease are associated with increased expression of 15-LOX-1 in bronchial epithelial cells, but the potential functions of 15-LOX-1 in airway epithelial cells have not been well clarified. To study the function of 15-LOX-1 in bronchial epithelial cells, we ectopically expressed 15-LOX-1 in the human lung epithelial cell line A549. We found that overexpression of 15-LOX-1 in A549 cells leads to increased release of the chemokines MIP-1α, RANTES, and IP-10, and thereby to increased recruitment of immature dendritic cells, mast cells, and activated T cells. These results suggest that an increased expression and activity of 15-LOX-1 in lung epithelial cells is a proinflammatory event in the pathogenesis of asthma and other inflammatory lung disorders.

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