Moderate hypothermia attenuates oxidative stress injuries in alveolar epithelial A549 cells

The treatment of severe lung disease often requires the use of high concentrations of oxygen coupled with the need for assisted ventilation, potentially exposing the pulmonary epithelium to both reactive oxygen species and nonphysiological cyclic stretch. Whereas prolonged hyperoxia is known to cause increased cell injury, cyclic stretch may result in either cell proliferation or injury depending on the pattern and degree of exposure to mechanical deformation. How hyperoxia and cyclic stretch interact to affect the pulmonary epithelium in vitro has not been previously investigated. This study was performed using human alveolar epithelial A549 cells to explore the combined effects of cyclic stretch and hyperoxia on cell proliferation and viability. Under room air conditions, cyclic stretch did not alter cell viability at any time point and increased cell number after 48 h compared with unstretched controls. After exposure to prolonged hyperoxia, cell number and [3H]thymidine incorporation markedly decreased, whereas evidence of oxidative stress and nonapoptotic cell death increased. The combination of cyclic stretch with hyperoxia significantly mitigated the negative effects of prolonged hyperoxia alone on measures of cell proliferation and viability. In addition, cyclic stretch resulted in decreased levels of oxidative stress over time in hyperoxia-exposed cells. Our results suggest that cyclic stretch, as applied in this study, can minimize the detrimental effects of hyperoxia on alveolar epithelial A549 cells.

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miR-486 inhibits PM2.5-induced apoptosis and oxidative stress in human lung alveolar epithelial A549 cells

Annals of Translational Medicine ◽

10.21037/atm.2018.06.09 ◽

2018 ◽

Vol 6 (11) ◽

pp. 209-209 ◽

Cited By ~ 14

Author(s):

Jin Li ◽

Qiulian Zhou ◽

Yajun Liang ◽

Wen Pan ◽

Yihua Bei ◽

...

Keyword(s):

Oxidative Stress ◽

Human Lung ◽

A549 Cells ◽

Alveolar Epithelial ◽

Induced Apoptosis ◽

And Oxidative Stress

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Dried Yeast Extracts Curtails Pulmonary Oxidative Stress, Inflammation and Tissue Destruction in a Model of Experimental Emphysema

Antioxidants ◽

10.3390/antiox8090349 ◽

2019 ◽

Vol 8 (9) ◽

pp. 349 ◽

Cited By ~ 2

Author(s):

Yun-Ho Kim ◽

Min-Kyung Kang ◽

Eun-Jung Lee ◽

Dong Kim ◽

Hyeongjoo Oh ◽

...

Keyword(s):

Oxidative Stress ◽

Pulmonary Emphysema ◽

Food Additives ◽

A549 Cells ◽

Lavage Fluid ◽

Tissue Destruction ◽

Alveolar Epithelial ◽

Umami Taste ◽

Tnf Α ◽

Species Production

Pulmonary emphysema is characterized by a loss of alveolar integrity due to prolonged cigarette smoking and inhaled irritants. Dried yeast extracts (YE) are employed as food additives, savory flavorings, or creation of umami taste sensations. Despite being rich in nutrition, their application as nutraceuticals and functional foods is not investigated much and little is known about the inhibition of pulmonary emphysema. This study examined whether YE ameliorated pulmonary emphysema in mice is evoked by cigarette smoke (CS) and ovalbumin (OVA). Mice were orally administrated with 25–100 mg/kg YE for 8 weeks. Alveolar epithelial A549 cells exposed to lipopolysaccharide or CS extracts (CSE) were supplemented with 10–100 µg/mL YE. Oral YE administration reduced bronchoalveolar lavage fluid leukocytosis in CS-/OVA-exposed mice. YE reduced induction of inflammatory mediators and MMP-12, and diminished reactive oxygen species production and emphysematous alterations in CS-challenged airways. The YE treatment blunted bax/bcl-2 ratio and activation of p53 and caspases in CS-exposed lungs. Apoptotic death was dampened in CSE-loaded YE-supplemented A549 cells. YE curtailed tissue levels of MMP-12 in inflammatory OVA-exposed lungs. YE abrogated the secretion of TNF-α and MCP-1 through blocking NF-κB signaling in endotoxin-loaded A549 cells. Thus, the antioxidant YE may therapeutically ameliorate oxidative stress and inflammatory tissue destruction in emphysematous diseases.

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Germinated Rhynchosia nulubilis Fermented with Lactobacillus pentosus SC65 Reduces Particulate Matter Induced Type II Alveolar Epithelial Apoptotic Cell Death

International Journal of Molecular Sciences ◽

10.3390/ijms22073660 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3660

Author(s):

Hye-Ji Lee ◽

Hye-Jin Park

Keyword(s):

Oxidative Stress ◽

Cell Death ◽

Particulate Matter ◽

Lung Injury ◽

A549 Cells ◽

Type Ii ◽

Caspase 9 ◽

Lactobacillus Pentosus ◽

Alveolar Epithelial ◽

Active Caspase

Particulate matter (PM) is a significant environmental pollutant that promotes respiratory diseases, including lung injury and inflammation, by inducing oxidative stress. Rhynchosia nulubilis (black soybean) is traditionally used to prevent chronic respiratory disease via inducing antioxidant and anti-inflammatory effects. To investigate the effects of Lactobacillus pentosus SC65 fermented GR (GR-SC65) and Pediococcus pentosaceus ON81A (GR-ON81A) against PM-induced oxidative stress and cell death in A549 cells, we performed the 2-7-dichlorodihydrofluorescein diacetate and cell counting kit-8 assays, as well as Hoechst 33342 and propidium iodide staining and western blotting. GR-SC65 showed the highest total polyphenolic contents and 1,1-diphenyl-2-picrylidrazil radical scavenging activity among lactic acid bacteria-fermented GRs (p < 0.001 vs. GR). Four soy peptides, β-conglycinin breakdowns (INAENNQRNF, ISSEDKPFN, LAFPGSAQAVEK, and LAFPGSAKDIEN), were detected in GR-SC65, but not in GR. In GR-SC65, PM-induced A549 cell death was less than that observed in GR-ON81A and GR (p < 0.001 vs. PM-treated group). GR-SC65 significantly decreased intracellular reactive oxidative species (ROS) when compared with PM (*** p < 0.001 vs. PM). GR-SC65 decreased the levels of BAX, active caspase-9, -3, and poly ADP-ribose polymerase (PARP) proteins (#p < 0.01, ###p < 0.001 vs. PM), while increasing the level of BCL-2 protein, a mitochondrial anti-apoptotic protein (###p < 0.001 vs. PM). Our findings indicate that GR-SC65 inhibited PM-induced cell death by suppressing the levels of ROS, active caspase-9 and -3, and PARP proteins, while enhancing the level of BCL-2 protein in type II alveolar epithelial A549 cells. Therefore, GR-SC65 might be a potential therapeutic and preventive agent against PM-induced lung injury.

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Nuclear Factor-kappaB Regulates the Transcription of NADPH Oxidase 1 in Human Alveolar Epithelial Cells

10.21203/rs.3.rs-132252/v1 ◽

2020 ◽

Author(s):

Weijing Wu ◽

Li Li ◽

Xiaoshan Su ◽

ZHIXING ZHU ◽

Xiaoping Lin ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

A549 Cells ◽

Alveolar Epithelial Cells ◽

Ros Generation ◽

Alveolar Epithelial ◽

Tnf Α ◽

Potential Regulatory Role ◽

Human Alveolar Epithelial Cells

Abstract Objective Acute lung injury (ALI) is characterized by inflammation and oxidative stress. Nuclear factor-kappaB (NF-κB) mediates the expression of various inflammation-related genes, including the NADPH oxidase family. This study aimed to identify the potential regulatory role of NF-𝜅B on NADPH oxidases in TNF-α-induced oxidative stress in human alveolar epithelial cells. Methods Type II alveolar epithelial cell-derived A549 cells were treated with TNF-α for 24 hours to establish ALI cell models. RT-PCR, western blot, DCFH-DA ROS assay, Alibaba 2.1 online analysis, electrophoretic mobility shift assays and luciferase reporter analysis were employed to identify the potential regulatory role of NF-𝜅B on NADPH oxidases in TNF-α-induced oxidative stress in human alveolar epithelial cells. Results The expression of NF-κB/p65 was notably upregulated in TNF-α-stimulated A549 cells. NF-κB knockdown by siRNA significantly inhibited the TNF-α-induced ROS generation. Moreover, NF-𝜅B/p65 siRNA could inhibite the activation of NOX1, NOX2 and NOX4 mRNA and protein expression in TNF-α-stimulated A549 cells. The next study demonstrated that NF-𝜅B activated the transcription of NOX1 by binding to the -261 to -252 bp (NOX1/κB2, TAAAAATCCC) region of NOX1 promoter in TNF-α-stimulated A549 cells. Conclusion Our data demonstrated that NF-κB can aggravate TNF-α-induced ALI by regulating the activation of ROS generation and the expression of NOX1, NOX2 and NOX4. Moreover, NF-𝜅B could promote the NOX1 transcriptional activity via binding its promoter in TNF-α-stimulated A549 cells.

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Nrf2 Alleviates TNF-α-Induced Oxidative Stress Damage in Type II Alveolar Epithelial Cells by Down-Regulating the Expression of NOX1

10.21203/rs.3.rs-68779/v1 ◽

2020 ◽

Author(s):

Weijing Wu ◽

Jiamin Zhang ◽

Xihua Lian ◽

Xiaoping Lin ◽

Xiaoshan Su ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Binding Site ◽

Luciferase Activity ◽

A549 Cells ◽

Alveolar Epithelial Cells ◽

Type Ii ◽

Alveolar Epithelial ◽

Tnf Α ◽

Stress Damage

Abstract Objective: To study the roles of Nrf2 in acute lung injury (ALI) pathogenesis by investigating the effects of Nrf2 on regulating oxidative stress damage in TNF-α-induced type II alveolar epithelial cells (T2AECs).Methods: T2AECs were transfected with Nrf2 siRNA and overexpression vectors for six hours before being induced by TNF-α for 24 hours. Subsequently, levels of interleukins (IL-6 and IL-8), reactive oxygen species (ROS), malondialdehyde (MDA), total antioxidation capability (T-AOC), Nrf2, NOX1 and NF-kB were measured. Additionally, potential Nrf2 binding site in NOX1 promoter was predicted by AliBaba2.1 and two recombinant vectors, namely “pGL3-NOX1-1500” and “pGL3-NOX1-1489, were constructed by inserting the sequence of NOX1 promoter in full-length and that in the absence of Nrf2 binding site to pGL3 basic vector. T2AECs were transfected with these vectors prior to TNF-α induction and the luciferase activity was measured.Results: Levels of IL-6, IL-8, ROS and MDA were increased (P＜0.05) while T-AOC was decreased in TNF-α-induced A549 cells after the transfection of Nrf2 siRNA vector (P＜0.05). In contrast, concentrations of IL-6, IL-8, ROS and MDA were decreased (P＜0.05) whereas T-AOC was increased after the transfection of Nrf2 overexpression vector (P＜0.05). NOX1 promoter possesses one Nrf2 binding site. Cells transfected by “pGL3-NOX1-1500” vector had the highest luciferase activity, followed by cells transfected by “pGL3-NOX1-1489” vector and the control cells (P＜0.05).Conclusion: Nrf2 modulates NOX1 expression via binding to its promoter, by which against TNF-α-induced oxidative stress damage in T2AECs. Thus, Nrf2 might be a therapeutic target for ALI.

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Nuclear factor-kappaB regulates the transcription of NADPH oxidase 1 in human alveolar epithelial cells

BMC Pulmonary Medicine ◽

10.1186/s12890-021-01464-z ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Weijing Wu ◽

Li Li ◽

Xiaoshan Su ◽

Zhixing Zhu ◽

Xiaoping Lin ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

A549 Cells ◽

Alveolar Epithelial Cells ◽

Nuclear Factor ◽

Alveolar Epithelial ◽

Tnf Α ◽

Potential Regulatory Role ◽

Human Alveolar Epithelial Cells

Abstract Objective Acute lung injury (ALI) is characterized by inflammation and oxidative stress. Nuclear factor-kappaB (NF-κB) mediates the expression of various inflammation-related genes, including the NADPH oxidase family. This study aimed to identify the potential regulatory role of NF-κB on NADPH oxidases in tumor necrosis factor-α (TNF-α)-induced oxidative stress in human alveolar epithelial cells. Methods A549 cells were treated with TNF-α for 24 h to establish ALI cell models. RT-PCR, western blot, assessment of oxidative stress, Alibaba 2.1 online analysis, electrophoretic mobility shift assays and luciferase reporter analysis were employed to identify the potential regulatory role of NF-κB on NADPH oxidases in TNF-α-induced oxidative stress in human alveolar epithelial cells. Results The expression of NF-κB/p65 was notably upregulated in TNF-α-stimulated A549 cells. NF-κB knockdown by siRNA significantly inhibited the TNF-α-induced oxidative stress. Moreover, NF-κB/p65 siRNA could inhibit the activation of NOX1, NOX2 and NOX4 mRNA and protein expression in TNF-α-stimulated A549 cells. The next study demonstrated that NF-κB activated the transcription of NOX1 by binding to the -261 to -252 bp (NOX1/κB2, TAAAAATCCC) region of NOX1 promoter in TNF-α-stimulated A549 cells. Conclusion Our data demonstrated that NF-κB can aggravate TNF-α-induced ALI by regulating the oxidative stress response and the expression of NOX1, NOX2 and NOX4. Moreover, NF-κB could promote the NOX1 transcriptional activity via binding its promoter in TNF-α-stimulated A549 cells.

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