• Tuberculosis and Respiratory Diseases
• /
• v.58 no.6
• /
• pp.590-599
• /
• 2005

Object : Cigarette smoking is a major cause of mucus hypersecretion, which is a pathophysiological feature of many inflammatory airway diseases. Mucins, which are an important part of the airway mucus, are synthesized from the Muc gene in airway epithelial cells. However, the signaling pathways for cigarette smoke-induced mucin synthesis are unknown. The aim of this study was to determine the signal pathway for smoking induced Muc5ac gene expression. Methods : A549 cells were cultured and transiently transfected with the Muc5ac promoter fragment. These cells were stimulated with 5% cigarette smoke extract (CSE) alone or with CSE after a pretreatment with various signal transduction pathway inhibitors (AG1478, PD98059 and SB203580). The Muc5ac promoter activity was examined using the luciferase reporter system, and the level of phosphorylated EGFR, ERK1/2, p38 MAPK and JNK were all examined using Western blot analysis. Muc5ac mRNA expression was also examined using reverse transcriptase polymerase chain reactions (RT-PCR). Results : 1. The peak level of luciferase activity of the Muc5ac promoter was observed at 5% concentration and after 3 hours of incubation with the CSE. The level of EGFR phosphorylation and the luciferase activity of the transfected cells caused by the CSE were significantly suppressed by AG1478 or PD98059 (P<0.01). 2. CSE phosphorylated ERK1/2 or p38 MAPK but not JNK. The Muc5ac mRNA expression level was increased by the CSE but that was suppressed by PD98059 or AG1478. 3. The CSE-induced phosphorylation of ERK1/2 was blocked by PD98059 and that of p38 MAPK was blocked by either PD98059 or SB203580. Either PD98059 or SB203580 suppressed the luciferase activity of the transfected cells (P<0.0001). Conclusion : The Muc5ac mRNA expression level was increased by the CSE. The increased CSE-induced transcriptional activity was mediated via EGF receptor activation, which led to ERK1/2 and p38 MAPK phosphorylation.

• Tuberculosis and Respiratory Diseases
• /
• v.80 no.1
• /
• pp.60-68
• /
• 2017

Background: Mucus hypersecretion from airway epithelium is a characteristic feature of airway inflammatory diseases. Tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) regulates mucin synthesis. Glucocorticoids including mometasone fuorate (MF) have been used to attenuate airway inflammation. However, effects of MF on mucin production have not been reported. Methods: Effects of MF and budesonide (BUD) on the phorbol-12-myristate-13-acetate (PMA)-induction of mucin and TNF-${\alpha}$ in human airway epithelial cells (NCI-H292) were investigated in the present study. Confluent NCI-H292 cells were pretreated with PMA (200 nM) for 2 hours. Subsequently, the cells were stimulated with MF (1-500 ng/mL) or BUD (21.5 ng/mL) for 8 hours. Dexamethasone ($1{\mu}g/mL$) was used as the positive control. Real-time polymerase chain reaction was used to determine MUC2 and MUC5AC mRNA levels. The level of total mucin, MUC2, MUC5AC, and TNF-${\alpha}$ in culture supernatants were measured using enzyme-linked immunosorbent assay. Results: MF and BUD significantly suppressed MUC2 and MUC5AC gene expression in PMA-stimulated NCI-H292 cells. The inhibitory effects of the two steroid drugs were also observed in the production of total mucin, MUC2 and MUC5AC proteins, and TNF-${\alpha}$. Conclusion: Our findings demonstrated that MF and BUD attenuated mucin and TNF-${\alpha}$ production in PMA-induced human airway epithelial cells.

• Biomolecules & Therapeutics
• /
• v.30 no.6
• /
• pp.540-545
• /
• 2022

Betulin is a triterpenoid natural product contained in several medicinal plants including Betulae Cortex. These medicinal plants have been used for controlling diverse inflammatory diseases in folk medicine and betulin showed anti-inflammatory, antioxidative, and anticancer activities. In this study, we tried to examine whether betulin exerts a regulative effect on the gene expression of MUC5AC mucin under the status simulating a pulmonary inflammation, in human airway epithelial cells. Confluent NCI-H292 cells were pretreated with betulin for 30 min and then stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 h or the indicated periods. The MUC5AC mucin mRNA expression and mucin glycoprotein production were measured by reverse transcription - polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. To elucidate the action mechanism of betulin, effect of betulin on PMA-induced nuclear factor kappa B (NF-kB) signaling pathway was also investigated by western blot analysis. The results were as follows: 1) Betulin significantly suppressed the production of MUC5AC mucin glycoprotein and down-regulated MUC5AC mRNA expression induced by PMA in NCI-H292 cells. 2) Betulin inhibited NF-κB activation stimulated by PMA. Suppression of inhibitory kappa B kinase (IKK) by betulin led to the inhibition of the phosphorylation and degradation of inhibitory kappa B alpha (IκBα), and the nuclear translocation of NF-κB p65. This, in turn, led to the down-regulation of MUC5AC glycoprotein production in NCI-H292 cells. These results suggest betulin inhibits the gene expression of mucin through regulation of NF-kB signaling pathway, in human airway epithelial cells.

• Biomolecules & Therapeutics
• /
• v.30 no.5
• /
• pp.473-478
• /
• 2022

In this study, we examined whether engeletin exerts an effect on the gene expression of MUC5AC mucin, in human pulmonary epithelial NCI-H292 cells. The cells were pretreated with engeletin for 30 min and stimulated with phorbol 12-myristate 13-acetate (PMA), for the following 24 h. The effect of engeletin on PMA-induced nuclear factor kappa B (NF-kB) signaling pathway was also investigated. Engeletin suppressed the mRNA expression and production of MUC5AC mucin, induced by PMA through the inhibition of degradation of inhibitory kappa Bα (IkBα) and NF-kB p65 nuclear translocation. These results suggest engeletin inhibits the gene expression of mucin through regulation of NF-kB signaling pathway, in human airway epithelial cells.

• Biomolecules & Therapeutics
• /
• v.31 no.5
• /
• pp.544-549
• /
• 2023

In this study, artesunate, an antimalarial agent, was investigated for its potential effect on the gene expression of airway MUC5AC mucin. The human pulmonary epithelial NCI-H292 cells were pretreated with artesunate for 30 min and then stimulated with phorbol 12-myristate 13-acetate (PMA), for the following 24 h. The effect of artesunate on PMA-induced nuclear factor kappa B (NF-kB) signaling pathway was also examined. Artesunate inhibited the glycoprotein production and mRNA expression of MUC5AC mucins, induced by PMA through the inhibition of degradation of inhibitory kappa Bα (IkBα) and NF-kB p65 nuclear translocation. These results suggest artesunate suppresses the gene expression of mucin through regulation of NF-kB signaling pathway, in human pulmonary epithelial cells.

• The Korean Journal of Physiology and Pharmacology
• /
• v.24 no.2
• /
• pp.157-163
• /
• 2020

Chronic inflammatory airway diseases, such as chronic rhinosinusitis, chronic obstructive pulmonary disease, and asthma, are associated with excessive mucus production. Hence, the regulation of mucus production is important for the treatment of upper and lower airway diseases. Eupatilin is a pharmacologically active ingredient obtained from Artemisia asiatica Nakai (Asteraceae) and exerts potent anti-inflammatory, anti-allergic, and anti-tumor activities. In the present study, we investigated the effect of eupatilin on phorbol 12-myristate 13-acetate (PMA)-induced MUC5AC and MUC5B expression in human airway epithelial cells. We found that eupatilin treatment significantly inhibited PMA-induced mucus secretion in PAS staining. In addition, qRT-PCR results showed that eupatilin dose-dependently decreased the mRNA expression of MUC5AC in human airway epithelial cells. Western blot and immunofluorescence assay also showed that PMA-induced protein expression of MUC5AC was inhibited by eupatilin treatment. Finally, we investigated MAPKs activity after stimulation with PMA using western blot analysis in human airway epithelial cells. The results showed that eupatilin downregulated the levels of phosphorylated p38, ERK, and JNK. In summary, the anti-inflammatory activities of eupatilin, characterized as the suppression of MUC5AC expression and secretion in human airway epithelial cells, were found to be associated with the inhibition of p38/ERK/JNK MAPKs signaling pathway of MUC5AC secretion.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.5
• /
• pp.589-597
• /
• 2015

It has been reported that overexpression of MUC5AC induced by excessive inflammation leads to airway obstruction in respiratory diseases such as chronic obstructive pulmonary disease and asthma. 15-Hydroxyeicosatetraenoic acid (15-HETE) has been reported to have anti-inflammatory effects, but the role of 15-HETE in respiratory inflammation has not been determined. Therefore, the aim of this study was to investigate the effects of 15-HETE on MUC5AC expression and related pathways. In this study, phorbol-12-myristate-13-acetate (PMA) was used to stimulate NCI-H292 bronchial epithelial cells in order to examine the effects of 15-HETE. 15-HETE inhibited PMA-induced expression of MUC5AC mRNA and secretion of MUC5AC protein. Moreover, 15-HETE regulated matrix metallopeptidase 9 (MMP-9), mitogen-activated protein kinase kinase (MEK), and extracellular signal-regulated kinase (ERK). In addition, 15-HETE decreased the nuclear translocation of specificity protein-1 (Sp-1) transcription factor and nuclear factor κB (NF-κB). Furthermore, 15-HETE enhanced the transcriptional activity of peroxisome proliferator-activated receptor gamma (PPARγ) as a PPARγ agonist. This activity reduced the phosphorylation of protein kinase B (PΚB/Akt) by increasing the expression of phosphatase and tensin homolog (PTEN). In conclusion, 15-HETE regulated MUC5AC expression via modulating MMP-9, MEK/ERK/Sp-1, and PPARγ/PTEN/Akt signaling pathways in PMA-treated respiratory epithelial cells.

• Korean Journal of Otorhinolaryngology-Head and Neck Surgery
• /
• v.61 no.12
• /
• pp.674-680
• /
• 2018

Background and Objectives The representative mucin genes in the human airway are MUC5AC and MUC5B, which are regulated by several inflammatory and anti-inflammatory substances. Triptolide (TPL), udenafil, betulinic acid, changkil saponin, and glucosteroid are some of the many anti-inflammatory substances that exist. TPL is a diterpenoid compound from the thunder god vine, which is used in traditional Chinese medicine for treatment of immune inflammatory diseases, such as rheumatoid arthritis, systemic lupus erythematosus, nephritis and asthma. However, the effects of TPL on mucin expression of human airway epithelial cells have yet to be reported. Hence, this study investigated the effect of TPL on lipopolysaccharide (LPS)-induced MUC5AC and MUC5B expression in human airway epithelial cells. Subjects and Method The NCI-H292 cells and the primary cultures of human nasal epithelial cells were used to investigate the effects of TPL on LPS-induced MUC5AC and MUC5B expression using real-time polymerase chain reaction, enzyme immunoassay, and Western blot. Results TPL significantly decreased the LPS-induced MUC5AC and MUC5B mRNA expression and protein production. TPL also significantly decreased the nuclear factor-kappa B (NF-kB) phosphorylation. Conclusion These results suggest that TPL down regulates MUC5AC and MUC5B expression via inhibition of NF-kB activation in human airway epithelial cells. This study may provide important information about the biological role of triptolide on mucus-secretion in airway inflammatory diseases and the development of novel therapeutic agents for controlling such diseases.

• Journal of Plant Biotechnology
• /
• v.49 no.1
• /
• pp.90-98
• /
• 2022

This study was performed to determine the optimal ratio for preparing an extract comprising the Ecklonia cava and Hizikia fusiformis complex as a therapeutic material for alleviating inflammatory respiratory diseases. First, to examine the optimal ratio for preparing the complex (SD-EH), Ecklonia cava and Hizikia fusiformis extracts were used; four extracts with different mixing ratios were prepared. The effects of the SD-EH extract on MUC5AC mRNA expression in PMA-treated NCI-H292 cells were analyzed; it was confirmed that the MUC5AC expression was significantly reduced after treatment with the SD-EHA-001 (E(100) : H(0)), SD-EHB-001 (E(90) : H(10)), SD-EHC-001 (E(80) : H(20)), and SD-EHD-001 (E(70) : H(30)) extracts. Western blotting was used to determine whether the SD-EH extract affects the expression levels of COX-2 and MMP-9 in PMA-treated A549 cells. The protein expression levels of COX-2 and MMP-9 were significantly lower (p < 0.001) in the cells treated with the SD-EHC-001 (E(80):H(20)), SD-EHD-001 (E(70) : H(30)), and SD-EHE-001 (E(60) : H(40) extracts than in the cells treated with PMA alone. The SD-EHC-001 (E(80) : H(20)) extract markedly downregulated the expression levels of MUC5AC, COX-2, and MMP-9. Therefore, the SE-EH extract may serve as a potential therapeutic agent for treating inflammatory respiratory diseases.

• Biomolecules & Therapeutics
• /
• v.31 no.3
• /
• pp.306-311
• /
• 2023

The current study aimed to reveal the potential effect of meclofenamate, a nonsteroidal anti-inflammatory drug, on the gene expression of airway MUC5AC mucin. Human pulmonary mucoepidermoid NCI-H292 cells were pretreated with meclofenamate for 30 min and stimulated with phorbol 12-myristate 13-acetate (PMA) for 24 h. Thereafter, the effect of meclofenamate on the PMA-induced nuclear factor kappa B (NF-kB) signaling pathway was assessed. Meclofenamate inhibited glycoprotein production and mRNA expression of MUC5AC mucins induced by PMA by inhibiting the degradation of inhibitory kappa Bα (IkBα) and NF-kB p65 nuclear translocation. These results suggest meclofenamate suppresses mucin gene expression by regulating NF-kB signaling pathway in human pulmonary epithelial cells.