ALKBH5 promotes cadmium-induced transformation of human bronchial epithelial cells by regulating PTEN expression in an m6A-dependent manner

Individuals exposed to dusts from concentrated animal feeding operations report increased numbers of respiratory tract symptoms, and bronchoalveolar lavage samples from such individuals demonstrate elevated lung inflammatory mediators, including interleukin (IL)-8 and IL-6. We previously found that exposure of bronchial epithelial cells to hog barn dusts resulted in a protein kinase C (PKC)-dependent increase in IL-6 and IL-8 release. We hypothesized that cattle feedlot dusts would also generate bronchial epithelial interleukin release in vitro. To test this, we used interleukin ELISAs and direct PKC isoform assays. We found that a dust extract from cattle feedlots [feedlot dust extract (FLDE)] augments PKC activity of human bronchial epithelial cells in vitro. A 5–10% dilution of FLDE stimulated a significant release of IL-6 and IL-8 at 6–24 h in a PKC-dependent manner vs. control medium-treated cells. An increase in PKCα activity was observed with 1 h of FLDE treatment, and PKCε activity was elevated at 6 h of FLDE exposure. The PKCα inhibitor, Gö-6976, did not inhibit FLDE-stimulated IL-8 and IL-6 release. However, the PKCε inhibitor, Ro 31-8220, effectively inhibited FLDE-stimulated IL-8 and IL-6 release. Inhibition of FLDE-stimulated IL-6 and IL-8 was confirmed in a dominant-negative PKCε-expressing BEAS-2B cell line but not observed in a PKCα dominant negative BEAS-2B cell line. These data support the hypothesis that FLDE exposure stimulates bronchial epithelial IL-8 and IL-6 release via a PKCε-dependent pathway.

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Exosomes derived from normal human bronchial epithelial cells down-regulate proliferation and migration of hydroquinone-transformed malignant recipient cells via up-regulating PTEN expression

Chemosphere ◽

10.1016/j.chemosphere.2019.125496 ◽

2020 ◽

Vol 244 ◽

pp. 125496 ◽

Cited By ~ 1

Author(s):

Zhenwei Lian ◽

Zuqing Hu ◽

Hongyi Xian ◽

Ran Jiang ◽

Haoyu Huang ◽

...

Keyword(s):

Epithelial Cells ◽

Bronchial Epithelial Cells ◽

Pten Expression ◽

Normal Human Bronchial Epithelial ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial ◽

Normal Human ◽

And Migration ◽

Proliferation And Migration

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STING Mediates Cytosolic Dna-Induced Muc5ac Mrna Expression in Human Bronchial Epithelial Cells

10.21203/rs.3.rs-37814/v1 ◽

2020 ◽

Author(s):

Masaya Ohta ◽

Yutaka Nishida ◽

Hisako Yagi ◽

Aikira Aizawa ◽

Takahito Oyanagi ◽

...

Keyword(s):

Epithelial Cells ◽

Mrna Expression ◽

Cell Types ◽

Bronchial Epithelial Cells ◽

Epithelial Cell Line ◽

Mrna Levels ◽

Dependent Manner ◽

Dna Sensing ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial

Abstract Background: Non-autologous and autologous cytosolic DNA are recognized as danger signals by cytoplasmic sensor molecules that activate signal-transduction pathways. An important molecule in cytosolic DNA sensing is stimulator of interferon genes (STING), an endoplasmic reticulum protein activated by cyclic GMP–AMP (cGAMP) produced in response to cytosolic DNA. STING is important for innate immune responses to cytosolic DNA in immune cells; however, knowledge about its role in bronchial epithelial cells is limited. Methods: We stimulated NCI-H292 cells with poly(dA:dT) and silenced STING and other regulatory proteins, and then determined MUC5AC mRNA expression levels. Results: Cytosolic DNA increased the expression of a major respiratory mucin protein, MUC5AC, in the human respiratory epithelial cell line NCI-H292 in a STING-dependent manner. Introducing poly(dA:dT) into the cytoplasm induced MUC5AC and interferon-β (IFNβ) expression. Silencing STING by RNA interference decreased poly(dA:dT)-induced MUC5AC mRNA expression but increased IFN-β mRNA levels. Furthermore, cGAMP treatment increased MUC5AC expression but not IFN-β expression. In contrast, silencing retinoic acid-inducible gene-I (RIG-I), which is a component of a different nucleic acid-sensing system, suppressed poly(dA:dT)-induced IFN-β expression and increased MUC5AC expression. Conclusions: Unlike its role in other cell types, in human bronchial epithelial cells, STING is central to cytosolic DNA-induced MUC5AC expression, whereas IFN-β expression is dependent on RIG-I. Our data indicate a functional interaction between the STING and RIG-I pathways, suggesting the existence of intricate and cell-specific cytosolic DNA-sensing systems.

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Differential effects of α- and β-defensin on cytokine production by cultured human bronchial epithelial cells

AJP Lung Cellular and Molecular Physiology ◽

10.1152/ajplung.00076.2004 ◽

2005 ◽

Vol 288 (3) ◽

pp. L508-L513 ◽

Cited By ~ 68

Author(s):

Noriho Sakamoto ◽

Hiroshi Mukae ◽

Takeshi Fujii ◽

Hiroshi Ishii ◽

Sumako Yoshioka ◽

...

Keyword(s):

Epithelial Cells ◽

Cytokine Production ◽

Airway Epithelial Cells ◽

Binding Activity ◽

Bronchial Epithelial Cells ◽

Dependent Manner ◽

Airway Epithelial ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial ◽

Cytokine Synthesis

Defensins are cysteine-rich cationic antimicrobial peptides that play an important role in innate immunity and are known to contribute to the regulation of host adaptive immunity. In addition to direct antimicrobial activities, it has been recently reported that α-defensins, mainly present in neutrophils in the lung, have a cytotoxic effect and induce IL-8 production from airway epithelial cells. Although β-defensins are expressed in epithelial cells in various tissues, including lung, there are no reports of their effects on cytokine synthesis in airway epithelial cells. The aim of the present study was to determine the effects of both α- and β-defensins on the cytokine production, transcription factor binding activity, and cytotoxicity in primary cultured human bronchial epithelial cells (HBECs). We used human neutrophil peptide-1 (HNP-1; α-defensin) and human β-defensin-2 (HBD-2) to stimulate HBECs. The results showed that treatment of HBECs with HNP-1, but not HBD-2, increased IL-8 and IL-1β mRNA expression in a dose-dependent manner and also enhanced IL-8 protein secretion and NF-κB DNA binding activity. The 24-h treatments with >20 μg/ml of HNP-1 or >50 μg/ml of HBD-2 were cytotoxic to HBECs. These results suggest that α- and β-defensins have different effects on cytokine synthesis by airway epithelial cells, and we speculate that they play different roles in inflammatory lung diseases.

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Identification of abnormally expressed lncRNAs induced by PM2.5 in human bronchial epithelial cells

Bioscience Reports ◽

10.1042/bsr20171577 ◽

2018 ◽

Vol 38 (5) ◽

Cited By ~ 9

Author(s):

Xing Li ◽

Mengning Zheng ◽

Jinding Pu ◽

Yumin Zhou ◽

Wei Hong ◽

...

Keyword(s):

Epithelial Cells ◽

Western Blot ◽

Mrna Expression ◽

Microarray Analysis ◽

Cell Apoptosis ◽

Expression Profiles ◽

Bronchial Epithelial Cells ◽

Dependent Manner ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial

To investigate the effect of stimulation of human bronchial epithelial cells (HBECs) by arterial traffic ambient PM2.5 (TAPM2.5) and wood smoke PM2.5 (WSPM2.5) on the expression of long non-coding RNAs (lncRNAs) in order to find new therapeutic targets for treatment of chronic obstructive pulmonary disease (COPD). HBECs were exposed to TAPM2.5 and WSPM2.5 at a series of concentrations. The microarray analysis was used to detect the lncRNA and mRNA expression profiles. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis and gene ontology (GO) enrichment were conducted to analyze the differentially expressed lncRNAs and mRNAs. Quantitative real-time PCR (qRT-PCR) was performed to confirm the differential expression of lncRNAs. Western blot was performed to study the expression of autophagy and apoptosis-associated proteins. Flow cytometry was used to detect the apoptotic cells. The results indicated that fine particulate matter (PM2.5)-induced cell damage of HBECs occurred in a dose-dependent manner. The microarray analysis indicated that treatment with TAPM2.5 and WSPM2.5 led to the alteration of lncRNA and mRNA expression profiles. LncRNA maternally expressed gene 3 (MEG3) was significantly up-regulated in HBECs after PM2.5 treatment. The results of Western blot showed that PM2.5 induced cell apoptosis and autophagy by up-regulating apoptosis-associated gene, caspase-3, and down-regulating autophagy-associated markers, Bcl-2 and LC3 expression. In addition, we demonstrated that TAPM2.5 and WSPM2.5 accelerated apoptosis of human bronchial (HBE) cells, silencing of MEG3 suppressed apoptosis and autophagy of HBE cells. These findings suggested that the lncRNA MEG3 mediates PM2.5-induced cell apoptosis and autophagy, and probably through regulating the expression of p53.

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Apple Flavonoids Suppress Carcinogen-Induced DNA Damage in Normal Human Bronchial Epithelial Cells

Oxidative Medicine and Cellular Longevity ◽

10.1155/2017/1767198 ◽

2017 ◽

Vol 2017 ◽

pp. 1-12 ◽

Cited By ~ 15

Author(s):

Vazhappilly Cijo George ◽

H. P. Vasantha Rupasinghe

Keyword(s):

Dna Damage ◽

Epithelial Cells ◽

Dna Fragmentation ◽

Bronchial Epithelial Cells ◽

Dependent Manner ◽

Normal Human Bronchial Epithelial ◽

Human Bronchial Epithelial Cells ◽

Bronchial Epithelial ◽

Repair Mechanisms ◽

Normal Human

Scope. Human neoplastic transformation due to DNA damage poses an increasing global healthcare concern. Maintaining genomic integrity is crucial for avoiding tumor initiation and progression. The present study aimed to investigate the efficacy of an apple flavonoid fraction (AF4) against various carcinogen-induced toxicity in normal human bronchial epithelial cells and its mechanism of DNA damage response and repair processes. Methods and Results. AF4-pretreated cells were exposed to nicotine-derived nitrosamine ketones (NNK), NNK acetate (NNK-Ae), methotrexate (MTX), and cisplatin to validate cytotoxicity, total reactive oxygen species, intracellular antioxidants, DNA fragmentation, and DNA tail damage. Furthermore, phosphorylated histone (γ-H2AX) and proteins involved in DNA damage (ATM/ATR, Chk1, Chk2, and p53) and repair (DNA-PKcs and Ku80) mechanisms were evaluated by immunofluorescence and western blotting, respectively. The results revealed that AF4-pretreated cells showed lower cytotoxicity, total ROS generation, and DNA fragmentation along with consequent inhibition of DNA tail moment. An increased level of γ-H2AX and DNA damage proteins was observed in carcinogen-treated cells and that was significantly (p≤0.05) inhibited in AF4-pretreated cells, in an ATR-dependent manner. AF4 pretreatment also facilitated the phosphorylation of DNA-PKcs and thus initiation of repair mechanisms. Conclusion. Apple flavonoids can protect in vitro oxidative DNA damage and facilitate repair mechanisms.

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