Induction of nitric oxide release from the human alveolar epithelial cell line A549: an <i>in vitro</i> correlate of innate immune response to <i>Mycobacterium tuberculosis</i>

Roy, Sugata; Sharma, Sadhna; Sharma, Monika; Aggarwal, Ramesh; Bose, Mridula

doi:10.1046/j.1365-2567.2004.01905.x

Cited by 61 publications

(69 citation statements)

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“…Early studies reported that Mtb could invade and multiply in alveolar epithelial cells [4, 8], and as a consequence, these cells are thought to play a significant role in the initial immunological host response against Mtb [27, 28]. …”

Section: Discussionmentioning

confidence: 99%

Water-pipe smoke condensate increases the internalization of Mycobacterium Bovis of type II alveolar epithelial cells (A549)

et al. 2017

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BackgroundTuberculosis (TB) is a major global health problem, and there is an association between tobacco smoke and TB. Water pipe smoking has become an increasing problem not only in Middle Eastern countries but also globally because users consider it as safer than cigarettes. The presence of high levels of toxic substances in water-pipe smoke may be a predisposing factor that enhances the incidence of pulmonary disorders. For example, uncontrolled macropinocytosis in alveolar epithelial cells following exposure to water-pipe smoke may predispose subjects to pulmonary infection. Here, we studied the effects of water-pipe condense (WPC) on the internalization of Mycobacterium Bovis BCG by macropinocytosis in the alveolar epithelial cell line A549.MethodsA549 cells were exposed to WPC (4 mg/ml) for 24, 48, 72 and 96 h. Cell viability was studied using the methyl thiazolyldipenyl-tetrazolium bromide (MTT) reduction assay and proliferation by bromodeoxyUridine (BrdU) incorporation. Cells were exposed to FITC-Dextran (1 mg/ml) (as a control) and FITC-BCG (MOI = 10) for 20 min at 37 °C before cells were collected and the uptake of BCG-FITC determined by flow cytometry. Similar experiments were performed at 4 °C as a control. The Rho-associated protein kinase (ROCK) inhibitor Y-27632 (1 μM) was used to assess the mechanism by which WPC enhanced BCG uptake.ResultsWPC (4 mg/ml) increased the uptake of BCG-FITC after 72 (1.3 ± 0.1 fold, p < 0.05) and 96 (1.4 ± 0.05 fold, p < 0.05) hours. No effect on BCG-FITC uptake was observed at 24 or 48 h. WPC also significantly increased the uptake of FITC-Dextran (2.9 ± 0.3 fold, p < 0.05) after 24 h. WPC significantly decreased cell viability after 24 (84 ± 2%, p < 0.05), 48 (78±, 3%, p < 0.05), 72 (64 ± 2%, p < 0.05) and 96 h (45 ± 2%, p < 0.05). Y-27632 completely attenuated the increased uptake of BCG by WPC. Cell proliferation showed a decreasing trend in a time-dependent manner with WPC exposure.ConclusionWPC exposure increased epithelial cell endocytosis activity and death as well as enhancing their capacity for macropinocytosis. Our in vitro data indicates possible harmful effects of WPC on the ability of lung epithelial cells to phagocytose mycobacterium.

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Section: Discussionmentioning

confidence: 99%

Water-pipe smoke condensate increases the internalization of Mycobacterium Bovis of type II alveolar epithelial cells (A549)

et al. 2017

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“…However, alveolar epithelial cells may not be a simple barrier, but respond to their microenvironment, induce various cytokines and chemokines, thus may contribute to the innate immune response during pulmonary TB (6). Indeed, infection of A549 cells with Mtb induced significant levels of nitric oxide (NO) and inducible NO synthase mRNA (6).…”

Section: Introductionmentioning

confidence: 99%

Mycobacterium tuberculosis Induces the Production of Tumor Necrosis Factor-α, Interleukin-6, and CXCL8 in Pulmonary Epithelial Cells Through Reactive Oxygen Species-dependent Mitogen-activated Protein Kinase Activation

Lee

Shin

2009

J Bacteriol Virol

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Upon contact with airway epithelial cells, mycobacteria activate several signal transduction events that are required for induction of inflammatory cytokines/chemokines. In this study, we found that Mycobacterium tuberculosis (Mtb)-induced reactive oxygen species (ROS) production is essential for the expression of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and CXC-chemokine ligand (CXCL) 8 through the activation of mitogen-activated protein kinases [MAPKs; extracellular signal-regulated kinase (ERK) 1/2 and p38 MAPK] in A549 cells representing alveolar epithelial cells. We observed that Mtb rapidly enhanced ROS production after stimulation in a toll-like receptor (TLR) 2-dependent manner. In addition, Mtb triggered ERK1/2 and p38 MAPK signaling pathways which were dependent on ROS generation in A549 cells. Moreover, Mtb stimulation significantly increased the secretion of TNF-α, IL-6, and CXCL8 over that in untreated controls. Pretreatment of A549 cells with the antioxidant, N-acetylcysteine and the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, diphenylene iodonium, substantially inhibited Mtb-induced production of TNF-α, IL-6, and CXCL8. Studies using inhibitors selective for ERK1/2 and p38 MAPK pathways showed that both pathways play an essential role in the induction of TNF-α, IL-6, and CXCL8 at transcriptional levels in A549 cells. Collectively, our findings indicate the critical role of TLR2-dependent ROS in the Mtb-induced inflammatory cytokine/chemokine production in alveolar epithelial cells through MAPK-dependent signaling pathways.

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“…The cells were shown to produce NO in response to M. tuberculosis infection. Their release of NO was increased by simultaneous stimulation with a mixture of TNF-␣, IL-1␤-, and IFN-␥, resulting in mycobactericidal activity (25).…”

mentioning

confidence: 99%

Roles of NF-κB Activation and Peroxisome Proliferator-Activated Receptor Gamma Inhibition in the Effect of Rifampin on Inducible Nitric Oxide Synthase Transcription in Human Lung Epithelial Cells

Yuhas

Berent²,

Cohen

et al. 2009

Antimicrob Agents Chemother

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Rifampin (rifampicin), an important antibiotic agent and a major drug used for the treatment of tuberculosis, exerts immunomodulatory effects. Previous studies have found that rifampin increases inducible nitric oxide (NO) synthase (iNOS) expression and NO production. The present study investigated the potential mechanism(s) underlying these actions. The incubation of human lung epithelial A549 cells with a cytokine mix (interleukin-1␤, tumor necrosis factor alpha, and gamma interferon) induced the expression of iNOS mRNA. The addition of rifampin increased the iNOS level by 1.9 ؎ 0.3-fold at a dose of 10 g/ml (P < 0.01) and by 4.0 ؎ 0.3-fold at a dose of 50 g/ml (P < 0.001). Rifampin treatment also affected the transcription factors that regulate iNOS mRNA: there was an increased and prolonged degradation of the inhibitory subunit of NF-B, a corresponding increase in the level of cytokine-induced DNA binding of NF-B (2.1 ؎ 0.2-fold), and a decrease in the level of expression of peroxisome proliferator-activated receptor gamma (PPAR␥). Specifically, the level of PPAR␥ expression dropped by 15% in response to cytokine stimulation and by an additional 40% when rifampin was added (P < 0.001). Rifampin had no effect on the activation of mitogen-activated protein kinases or the signal transducer and transcription activator (STAT-1). In conclusion, rifampin augments NO production by upregulating iNOS mRNA. It also increases the level of NF-B activation and decreases the level of PPAR␥ expression. The increases in the levels of NF-B activation and NO production probably contribute to the therapeutic effects of rifampin. However, given the role of NF-B in upregulating many inflammatory genes and the roles of PPAR␥ in downregulating inflammatory genes and in lipid and glucose metabolism, these findings have implications for potential adverse effects of rifampin in patients with chronic inflammatory diseases and glucose or lipid disorders.

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Induction of nitric oxide release from the human alveolar epithelial cell line A549: an in vitro correlate of innate immune response to Mycobacterium tuberculosis

Cited by 61 publications

References 40 publications

Water-pipe smoke condensate increases the internalization of Mycobacterium Bovis of type II alveolar epithelial cells (A549)

Water-pipe smoke condensate increases the internalization of Mycobacterium Bovis of type II alveolar epithelial cells (A549)

Mycobacterium tuberculosis Induces the Production of Tumor Necrosis Factor-α, Interleukin-6, and CXCL8 in Pulmonary Epithelial Cells Through Reactive Oxygen Species-dependent Mitogen-activated Protein Kinase Activation

Roles of NF-κB Activation and Peroxisome Proliferator-Activated Receptor Gamma Inhibition in the Effect of Rifampin on Inducible Nitric Oxide Synthase Transcription in Human Lung Epithelial Cells

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