Increased susceptibility of cystic fibrosis airway epithelial cells to ferroptosis

BACKGROUND: Defective chloride transport in airway epithelial cells (AECs) and the associated lung disease are the main causes of morbidity and early mortality in cystic fibrosis (CF). Abnormal airway iron homeostasis and the presence of lipid peroxidation products, indicative of oxidative stress, are features of CF lung disease. RESULTS: Here, we report that CF AECs (IB3-1) are susceptible to ferroptosis, a type of cell death associated with iron accumulation and lipid peroxidation. Compared to isogenic CFTR corrected cells (C38), the IB3-1 cells showed increased susceptibility to cell death upon exposure to iron in the form of ferric ammonium citrate (FAC) and the ferroptosis inducer, erastin. This phenotype was accompanied by accumulation of intracellular ferrous iron and lipid peroxides and the extracellular release of malondialdehyde, all indicative of redox stress, and increased levels of lactate dehydrogenase in the culture supernatant, indicating enhanced cell injury. The ferric iron chelator defer-oxamine (DFO) and the lipophilic antioxidant ferrostatin-1 inhibited FAC and erastin induced ferroptosis in IB3-1 cells. Glutathione peroxidase 4 (GPX4) expression was decreased in IB3-1 cells treated with FAC and erastin, but was unchanged in C38 AECs. Necroptosis appeared to be involved in the enhanced susceptibility of IB3-1 AECs to ferroptosis, as evidenced by partial cell death rescue with necroptosis inhibitors and enhanced mixed lineage kinase domain-like (MLKL) localisation to the plasma membrane. CONCLUSION: These studies suggest that the increased susceptibility of CF AECs to ferroptosis is linked to abnormal intracellular ferrous iron accumulation and reduced antioxidant defences. In addition, the process of ferroptotic cell death in CF AECs does not appear to be a single entity and for the first time we describe necroptosis as a potential contributory factor. Iron chelation and antioxidant treatments may be promising therapeutic interventions in cystic fibrosis.

Mechanisms of cross-species transmission of H7N9 avian influenza virus and its pathological features in airway epithelium: Research progress / 解放军医学杂志

H7N9 avian influenza is a new subtype of avian influenza, first found in the Yangtze River Delta at the end of February 2013. H7N9 avian influenza, infection in human is transmitted through the respiratory airway, causing acute respiratory infectious disease. Due to the species barrier, H7N9 avian influenza virus only infect human via birds occasionally under very specific circumstances, and at present, there is no exact evidence of H7N9 avian influenza virus transmission between humans. However, H7N9 avian influenza remains a continuous public health threat. So far, China has had six outbreaks of H7N9 avian influenza. A total of 1567 cases of H7N9 influenza virus infection have been reported to WHO, including 615 deaths. When H7N9 avian influenza virus infects the human body, their primary target of infection is the respiratory mucosal epithelial cells. Therefore, the respiratory epithelium plays a key role in the process of virus transmission and infection. Hence, the main purpose of this review is to collate the current understanding of immune responses and their corresponding molecular mechanisms of mucosal damage caused by H7N9 avian influenza infection, and how it contributes to cross species human infection.

Effect of Resolvin D1 and E1 on Mucin Expression in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Mucin is an important component of mucus that performs the first line of defense against inhaled pathogens and particles, lubrication of organs, and protection of airway. It is hyper-secreted in inflammatory airway diseases and is associated with morbidity and mortality of the affected patients. Resolvin, an autacoid of a specific lipid structure, exhibits anti-inflammatory property against inflammatory airway diseases although its effects on mucin secretion by human airway epithelial cells have not yet been demonstrated. In this regard, we investigated the effects of Resolvin on lipopolysaccharide (LPS)-induced mucin expression in human airway epithelial cells. MATERIALS AND METHOD: In mucin-producing human NCI-H292 epithelial cells, the effects and brief signaling pathways of Resolvin D1 (RvD1) and Resolvin E1 (RvE1) on the LPS-induced MUC4, MUC5AC, and MUC5B expression were investigated using reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay and Western blot analysis. RESULTS: RvD1 attenuated LPS-induced MUC4, MUC5AC, and MUC5B mRNA expression and protein production in human NCI-H292 cells while RvE1 did not. RvD1 significantly blocked LPS-induced activated phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) and p38 MAPK and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) while RvE1 did not. CONCLUSION: These results suggest that RvD1 attenuates LPS-induced MUC4, MUC5AC, and MUC5B expressions via ERK1/2 MAPK, p38 MAPK, and NF-κB signaling pathways in airway epithelial cells. Therefore, RvD1 may modulate the control of mucus-hypersecretion in inflammatory airway diseases.

Inhibitory Effects of Protopanaxadiol on Lipopolysaccharide-Induced Reactive Oxygen Species Production and MUC5AC Expression in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: MUC5AC is one of the major secretory mucin genes in the human airway epithelium. MUC5AC expression is increased by a variety of inflammatory mediators. Protopanaxadiol (PPD), one of the major active metabolites in ginseng, is known to have anti-inflammatory, antitumor and antioxidant properties. However, the effects of PPD on mucin secretion of airway epithelial cells still have not been reported. Therefore, the aim of this study is to investigate the effect of PPD on lipopolysaccharide (LPS)-induced MUC5AC expression in human airway epithelial cells. MATERIALS AND METHOD: In the mucin-producing human NCI-H292 airway epithelial cells, the effect of PPD on MUC5AC expression was investigated using reverse transcription-polymerase chain reaction and enzyme immunoassay after treated with LPS. N-acetylcysteine (NAC) as a reactive oxygen species (ROS) scavenger, and apocynin as a nicotinamide adenine dinucleotide phosphate oxidase inhibitor were used to compare the inhibitory effect of PPD on LPS-induced ROS production in human NCI-H292 cells. RESULTS: LPS significantly increased MUC5AC mRNA expression and protein production. LPS also increased ROS production. PPD inhibited LPS-induced MUC5AC mRNA expression and protein production as well as ROS production. In addition, NAC and apocynin inhibited LPS-induced MUC5AC mRNA expression and protein production. CONCLUSION: These results demonstrate that PPD inhibits LPS-induced MUC5AC expression via ROS in human airway epithelial cells and the inhibitory effect of PPD was similar to that of NAC and apocynin. These findings indicate that PPD may be a therapeutic agent for control of mucus secretion and oxidative stress in human airway epithelial cells.

Triptolide Inhibits Lipopolysaccharide-Induced MUC5AC/5B Expression via Nuclear Factor-Kappa B in Human Airway Epithelial Cells / 대한이비인후과학회지

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.

Updates on airway epithelial cells in asthma / 国际儿科学杂志

Airway epithelial cells,which are the first line of defense against inhaled pathogens and parti-cles,play an important role in initiating airway inflammation,mucous metaplasia and keeping type 2 inflamma-tion in asthma.Mucous metaplasia of airway epithelial cells is one of the important part of airway reconstitution. The mucous overproduction in small airway leads to mucous plug,which is closely related to the high mortality of asthma.Multiple signaling and transcriptional networks influence goblet cell differentiation.These include JAK and the transcription factor STAT6,Notch,EGFR,et al.In this article,the changes of epithelial cells in asthma and its role at the beginning of asthma are described.Furthermore,the progress in airway mucous metaplasia and several related cell signaling pathways were focused on,which may provide some potential target to inhibit the secretion of mucous in asthma.

Immunoregulation by airway epithelial cells (AECs) against respiratory virus infection / 解放军医学杂志

The respiratory tract is primary contact site of the body and environment,and it is ventilated by 10-20 thousand liters of air per day.Inevitably,the respiratory system comes into contact with airborne microbes,which contain the disease-causing pathogens.Airway epithelial cells (AECs) are known to have innate sensor functions,which are similar to the "professional" immune cells,such as alveolar macrophage and sub-or intra-epithelial dendritic cells (DCs).Thus AECs are able to detect invading microbial danger including different types of respiratory viruses,and mount a potent host response,for example,activating type Ⅰ interferon signaling pathway genes.To avoid chronic inflammation and maintain the immunological homeostasis,the pulmonary system has developed intrinsic mechanisms to control local immune responses.Most recently,the role of AECs in control of local immunity has gained much attention,as 1) AECs express the pattern recognition receptors (PRRs),such as Toll-like receptors,retinoic acid inducible gene Ⅰ (RIG-Ⅰ)-like receptor,and so on,thus AECs are equipped to Participate in innate detection of microbial encounter;2) To keep immunological homeostasis in the respiratory tract,AECs behave not only as innate immune sensors but also as immune modulators in parallel,through modulating the sensitivity of innate immune sensing of both AECs per se and sub-or intra-epithelial immune cells;3) Loss of modularity capacity of AECs might be involved in the development of chronic airway diseases.In present review,how the AECs act will be intensively discussed in response to respiratory viruses and modulate the local immunity through cis-and trans-factors (direct and indirect factors),as well as the consequence of impairment of this control of local immunity,in the development and exacerbation of airway diseases,such as acute and chronic rhinosinusitis.

Effects of different titers of bacteriophage D29 on growth and function of airway epithelia cell 9HTE / 重庆医学

Objective To research the effects of different titers of bacteriophage D29 on growth and function of airway epithelial cell 9HTE.Methods Cell viability rates was analyzed after applying high(109 PFU/mL)and low(107 PFU/mL)titers of bacteriophage D29 and phage buffer respectively by MTT colorimetry.Additionally,the secretion levels of IL-6,IL-8 in cell culture supernatant were detected by ELISA.RT-PCR was performed to detect the expression of ICAM-1 mRNA.Cell apoptosis rate was analyzed by flow cytometry.Results There was no difference in cell growth,secretion levels of IL-6,IL-8,ICAM-1 mRNA and cell apoptosis rate between cells treated with high and low titers of D29 and phage buffer(P>0.05).Conclusion Neither high nor low titer of bacteriophage D29 exerts effect on growth and function of airway epithelial cell 9HTE in vitro.

Asian Sand Dust Up-Regulates MUC4 Expression in Human Upper Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Asian sand dust (ASD) is a meteorological phenomenon that occurs in spring time in Korea. ASD is composed of various organic and inorganic materials, which induce airway inflammation. MUC4 is an important membrane-bound mucin gene in the human airway, and its expression is increased in pathologic proliferative lesions such as nasal polyps. However, the effect of ASD on MUC4 in human airway epithelial cells is unclear. Therefore, this study aimed to investigate the effect and signaling pathway of ASD on MUC4 expressions in human airway epithelial cells. METERIALS AND METHOD: The effect and signaling pathway of ASD on MUC4 expressions were investigated in NCI-H292 cells and in the primary cultures of human nasal epithelial cells using reverse transcription-polymerase chain reaction, real-time polymerase chain reaction, enzyme immunoassay, and immunoblot analysis with several specific inhibitors and small interfering ribonucleic acid (siRNA). RESULTS: ASD induced MUC4 expression and the activated the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK). An ERK1/2 MAPK inhibitor and a p38 MAPK inhibitor inhibited the ASD-induced MUC4 expression. In addition, the knockdowns of ERK1, ERK2 and p38 MAPK by the respective siRNA blocked the ASD-induced MUC4 mRNA expression. ASD induced toll-like receptor 4 (TLR4) mRNA expression. The knockdown of TLR4 by TLR4 siRNA blocked the phosphorylation of ERK1/2 and p38 MAPK, and the ASD-induced MUC4 mRNA expression. CONCLUSION: These results show that ASD induces MUC4 expressions via TLR4-dependent ERK1/2 and p38 MAPK signaling pathway in human airway epithelial cells.

Advances on abnormal expression of E-cadherin with bronchial asthma / 中国药理学通报

Bronchial asthma is a kind of respiratory disease which affects people 's life quality seriously. Many factors in-volved in the occurrence and development of such disease, of which the aberrant expression of E-cad plays a critical role in it. Research found that E-cad is an important cell adhesion molecu-lar, and its main function is to maintain the structural integrity of cells and participate in the improvement of airway remodeling as well as restoration of immune function. Further study showed that the role of mucosal barrier of airway epithelial cells in bronchial asthma patients was often damaged. Moreover, the protein ex-pression of E-cad decreased significantly in mucosal molecular, which suggested that the abnormal expression of E-cad was in-volved in the development of bronchial asthma. A review on the relations between the abnormal expression of E-cad protein and bronchial asthma has been discussed in this paper, also it in-cludes the discussion about the mechanisms of E-cad’ s disorder-induced bronchial asthma as well as explores the strategies of bronchial asthma treatment, which may provide references for the follow-up research and clinical treatment.

Effect of Multi-Walled Carbon Nanotubes on MUC5AC and MUC5B Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Multi-walled carbon nanotubes (MWCNT) are one of the most commonly used nanomaterials to date. Recent studies have demonstrated that MWCNT increase immune response and allergic inflammation in airway epithelial cells. However, the effects of MWCNT on mucin in human airway epithelial cells have not been reported. Therefore, in the present study, the effect of MWCNT on MUC16, MUC5AC, and MUC5B expressions were investigated in human airway epithelial cells. SUBJECTS AND METHOD: In mucin-producing human NCI-H292 airway epithelial cells and primary cultures of normal nasal epithelial cells, the effects of MWCNT on MUC16, MUC5AC, and MUC5B expression were analyzed by reverse transcription polymerase chain reaction, real-time polymerase chain reaction, and enzyme-linked immunosorbent assay. RESULTS: In human NCI-H292 airway epithelial cells, MWCNT significantly induced the expression MUC5AC and MUC5B mRNA and the production of MUC5AC and MUC5B protein. However, MWCNT did not induce the expression of MUC16 mRNA. In the primary cultures of normal nasal epithelial cells, MWCNT also induced the expression of MUC5AC and MUC5B mRNA and the production of MUC5AC and MUC5B proteins. CONCLUSION: The results of this study demonstrate that MWCNT induces MUC5AC and MUC5B expression in human airway epithelial cells. These findings provide important information about the biological role of MWCNT on mucus-secretion in human airway epithelial cells.

Effect of Polyinosinic-Polycytidylic Acid on MUC5B Expression in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Polyinosinic-polycytidylic acid (Poly I:C) is structurally similar to double-stranded RNA, and is known to induce various inflammatory mediators and to cause inflammatory reactions in airway epithelial cells. However, the effect of Poly I:C on secretion of mucins in human airway epithelial cells has been very rarely reported. In this study, the effect and brief signaling pathway of Poly I:C on the expression of mucin genes were investigated in human airway epithelial cells. MATERIALS AND METHOD: In mucin-producing human NCI-H292 airway epithelial cells and the primary cultures of normal human nasal epithelial cells, the effect and signaling pathway of Poly I:C on expression of mucin genes were investigated using reverse transcriptase-polymerase chain reaction, real-time PCR, enzyme immunoassay, and immunoblot analysis with specific inhibitors and small interfering RNA (siRNA) for mitogen-activated protein kinase (MAPK). RESULTS: Poly I:C induced the MUC5B expression, and activated the phosphorylation of ERK1/2 and p38 MAPK. U0126 (ERK1/2 MAPK inhibitor) and SB203580 (p38 MAPK inhibitor) inhibited the Poly I:C-induced MUC5B expression. In addition, the knockdown of ERK2 and p38 MAPK by siRNA significantly blocked the Poly I:C-induced MUC5B mRNA expression. CONCLUSION: Poly I:C induces the MUC5B expression via ERK2 and p38 MAPK signaling pathways in human airway epithelial cells. Therefore, Poly I:C may play a role in the regulation of mucus hypersecretion through MAPK signaling pathways in the human airway epithelial cells.

Roflumilast Attenuates MUC5AC and MUC5B Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Roflumilast, a selective inhibitor of phosphodiesterase type 4, has an anti-inflammatory property. It has been used in the treatment of chronic inflammatory airway diseases such as chronic obstructive pulmonary disease and asthma. However, the effect of roflumilast on mucus secretion in inflammatory airway epithelial cells has not been reported. Therefore, this study was aimed at investigating the effects of roflumilast on the inflammatory mediator-induced MUC5AC and MUC5B expression in human airway epithelial cells. MATERIALS AND METHOD: In human mucin-producing NCI-H292 airway epithelial cells and primary cultures of nasal epithelial cells, the effects of roflumilast on lipopolysaccharide (LPS)- and phorbl-12-myrsitate-13-acetate (PMA)-induced MUC5AC and MUC5B expression were analyzed by reverse transcription polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: Roflumilast attenuated LPS-induced MUC5AC and MUC5B mRNA and glycoprotein expression in NCI-H292 cells. And roflumilast attenuated PMA-induced MUC5AC and MUC5B mRNA and glycoprotein expression in NCI-H292 cells. In addition, roflumilast attenuated LPS and PMA-induced MUC5AC and MUC5B mRNA expression in the primary cultures of nasal epithelial cells. CONCLUSION: These results suggest that roflumilast attenuates MUC5AC and MUC5B expressions in airway epithelial cells. Roflumilast may be a potentially ideal therapeutic agent for the control of mucus-hypersecretion in treating chronic inflammatory airway diseases.

Effect of Betulinic Acid on MUC5AC and MUC5B Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: MUC5AC and MUC5B are representative secretory mucin genes in the human airway, whose expressions are increased by a variety of inflammatory mediators. Betulinic acid, a naturally occurring pentacyclic triterpenoid, is known to have an anti-inflammatory property. However, the effects of betulinic acid on mucin secretion of airway epithelial cells still have not been reported. Therefore, in this study, the effect of betulinic acid on inflammatory mediators-induced MUC5AC and MUC5B expressions was investigated in human airway epithelial cells. SUBJECTS AND METHOD: In the mucin-producing human NCI-H292 airway epithelial cells, the effects of betulinic acid on interleukin-1beta (IL-1beta)-, lipopolysaccharide (LPS)-, and phorbol myristate acetate (PMA)-induced MUC5AC and MUC5B expressions were analyzed by reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: Betulinic acid attenuated IL-1beta-, LPS-, and PMA-induced MUC5B mRNA and glycoprotein expression in NCI-H292 cells. On the other hand, betulinic acid did not attenuate IL-1beta-, and LPS-, but induced PMA-induced MUC5AC mRNA and glycoprotein expressions in NCI-H292 cells. CONCLUSION: These results suggest that betulinic acid attenuates IL-1beta-, LPS-, and PMA-induced MUC5B expression in the airway epithelial cells. Therefore, betulinic acid may modulate a control of mucus-hypersecretion in airway inflammatory diseases.

Effect of Anthocyanidin on MUC5AC and MUC5B Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Naringenin and delphinidin are types of anthocyanidin, which are flavonoids and thus have anti-inflammatory property. Moderate consumption of natural dietary naringenin and delphinidin is believed to do anti-inflammatory action, but the action mechanism is unclear. Therefore, this study aimed to investigate the effects of naringenin and delphinidin on interleukin-1beta (IL-1beta)- and lipopolysaccharide (LPS)-induced MUC5AC and MUC5B expressions in airway epithelial cells. MATERIALS AND METHOD: In NCI-H292 cells and cultured nasal polyp epithelial cells, the effects of naringenin and delphinidin on IL-1beta- and LPS-induced MUC5AC and MUC5B expressions were analyzed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. RESULTS: Delphinidin attenuated IL-1beta- and LPS-induced MUC5AC and MUC5B mRNA and glycoprotein expression in a dose-dependent pattern in NCI-H292 cells and in cultured nasal polyp epithelial cells. Naringenin partially attenuated IL-1beta- and LPS-induced MUC5AC and MUC5B mRNA and glycoprotein expression at a high dose. CONCLUSION: These results suggest that delphinidin attenuates MUC5AC and MUC5B expressions in the airway epithelial cells. Between anthocyanidin and delphinidin, delphinidin exhibits greater potential as an ideal therapeutic agent for the control of mucus-hypersecretion in the treatment of airway inflammatory diseases.

Effect of Udenafil on MUC5B Expression in Human Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Mucus hypersecretion in the airway may lead to increased frequency and duration of infection, declined lung function, and increased morbidity and mortality in inflammatory respiratory diseases. Udenafil, a phosphodiesterase (PDE) 5 inhibitor, is an oral medication for erectile dysfunction. Recent studies show that PDE5 inhibitor has various anti-inflammatory properties. However, the effect of udenafil on mucus secretion in human airway epithelial cells is unclear. Therefore, the effect and brief signaling pathway of udenafil on MUC5B expression were investigated in human airway epithelial cells. MATERIALS AND METHOD: We analyzed the effects and brief signaling pathway of udenafil on the lipopolysaccharide (LPS) induced MUC5B expression in mucin-producing NCI-H292 epithelial cells using reverse transcription-polymerase chain reaction, enzyme-linked immunosorbent assay, and immunoblot analysis. RESULTS: Udenafil attenuated the LPS-induced MUC5B mRNA expressions and glycoprotein production in NCI-H292 epithelial cells. It also attenuated LPS-induced toll like receptor 4 (TLR4) mRNA expression and phosphorylation of extracellular regulated kinase1/2 (ERK1/2) and p38 in NCI-H292 epithelial cells. CONCLUSION: These results suggest that udenafil attenuates the LPS induced MUC5B expression via TLR4, ERK1/2 and p38 mitogen activated protein kinase (MAPK) pathway in human airway epithelial cells, and that it could be a novel therapeutic agent for controlling chronic airway disease.

Differences of the regulation on the expression of mucin 1 ( MUC1 ) induced by adenovirus serotype 5 and serotype 7 infections in airway epithelial cells / 中华微生物学和免疫学杂志

Objective To explore the molecular mechanism for the self-limitation of adenoviral infections in human airway,the different impacts of adenovirus serotype 5 ( Ad5 ) and serotype 7 ( Ad7 ) infections on mucin 1 ( MUC1 ) expression in airway epithelial cells were preliminarily investigated.Methods The Ad5 and the Ad7 infection models were established in A549 cell line.qRT-PCR was performed to determine the transcription of MUC1 mRNA,and the expression of MUC1 in A549 cells infected by Ad5 or Ad7 was by detected Western blot.Results An up-regulation of the MUC1 mRNA level were observed after Ad5 infection for 6 h(P＜0.05 ),and the protein expression level of MUC1 increased in a time-dependent manner in 48 hours of Ad5 infection,while similar response of MUC1 mRNA was absent in Ad7 infection (6 h),even after prolonged (20 h) treatment ( P ＞ 0.05 ).Conclusion This study reveals an up-regulation of MUC1 expression as one of the early immune response to Ad5 infection,which implies that MUC1 may function fully or partially as an anti-inflammatory factor in the self-limitation effect of Ad5 infection.However,type7 adenoviral infection,may introduce a mechanism otherwise,but through MUC1.

Effects of Scutellarin on MUC5AC Mucin Production Induced by Human Neutrophil Elastase or Interleukin 13 on Airway Epithelial Cells

Scutellarin is a flavonoid extracted from a traditional Chinese herb, Erigeron breviscapus. The present study investigated the effect of scutellarin on MUC5AC mucin production and the possible mechanism. Human bronchial epithelial 16 (HBE16) cells were pretreated with scutellarin for 60 min, and then exposed to human neutrophil elastase (HNE) or interleukin (IL)-13 for 12 hr. RT-PCR and ELISA were performed to measure the amount of MUC5AC mucin production. The results showed that scutellarin inhibited MUC5AC expression both in mRNA and protein level induced by HNE in a concentration-dependent manner. However, scutellarin failed to inhibit MUC5AC mucin production induced by IL-13. To investigate the intracellular mechanisms associated with the effect of scutellarin on MUC5AC mucin production, western blotting was carried out to examine the phosphorylation of protein kinase C (PKC), signal transducer and activator of transcription 6 (STAT6) and extracellular signal-regulated kinase 1/2 (ERK1/2). The phosphorylation of PKC and ERK1/2 was attenuated after treatment with scutellarin, whereas STAT6 was not significantly affected. Therefore, it is suggested that scutellarin down-regulates MUC5AC mucin production on HBE16 cells via ERK-dependent and PKC-dependent pathways.

Rhinovirus-Induced Mucin Gene Expression in Airway Epithelial Cells / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: It is unclear whether rhinovirus infections promote mucus secretion in airway epithelial cells. Increase of mucin gene expression and mucin production is associated with mucus hypersecretion. We therefore investigated the effect of rhinovirus infection on mucin gene expression in airway epithelial cells. MATERIALS AND METHOD: The effect of rhinovirus-16 infection on the gene expression of MUC- 5AC, MUC5B, MUC6, MUC7, and MUC8 was evaluated using semi-quantitative reverse transcription polymerase chain reaction in A549 cells. RESULTS: Rhinovirus significantly increased MUC5AC, MUC7, and MUC8 messenger ribonucleic acid (mRNA) expressions in A549 cells, but it did not significantly affect the expression of MUC5B and MUC6 mRNA. CONCLUSION: This results show that rhinovirus may induce mucus secretion in airway epithelial cells.

Signal mechanism of endothelin-1-mediated activation of airway fibroblasts induced by injured airway epithelial cells / 中国病理生理杂志

AIM: To explore the effects of p38 mitogen-activated protein kinases (MAPK) and phosphoinositide 3-kinases (PI3K)/Akt on interleukin (IL)-6, the endothelin (ET)-1-mediated process of airway fibroblast activation induced by injured human bronchial epithelial cells (HBE). METHODS: Human primary cultured airway fibroblasts were co-cultured with HBE pre-treated with or without poly-L-arginine (PLA). The procedure was also performed in the presence or absence of p38 MAPK selective inhibitor SB203580, PI3K selective inhibitor LY294002 or ETA receptor blocker BQ123, respectively. Immunostaining, Western blotting or ELISA were used for detecting α-smooth muscle actin (α-SMA) expression, the activities of p38 MAPK and Akt in fibroblasts or IL-6 levels in supernatants of fibroblasts. In addition, fibroblasts were mixed with soluble collagen and cultured with HBE treated as the same mentioned above, the gel contraction was measured by serial area measurements. RESULTS: ET-1 and IL-6 levels [(13.69±1.36) ng/L, (56.7±10.7) ng/L] in the supernatants of fibroblasts cultured with injured HBE were significantly higher than those in the supernatants of fibroblasts cultured with HBE [(3.79±0.64) ng/L, (15.5±3.2) ng/L]. BQ123, SB203580 or LY294002 decreased IL-6 levels [(27.2±3.1) ng/L, (31.5±3.6) ng/L, (41.3±3.2) ng/L] differently in the supernatants of fibroblasts induced by injured HBE. Activation of p38 MAPK preceded Akt in fibroblasts cultured with injured HBE. BQ123 reduced the phosphorylation levels of p38 MAPK and Akt. SB203580 concentration-dependently attenuated Akt phosphorylation, while LY294002 had little effect on p38 MAPK phosphorylation. Fibroblasts expressed more α-SMA after cultured with injured HBE and showed significant increase in the gel contraction compared to fibroblasts cultured with HBE [percentage of gel contraction: (61.2±2.7)% vs (15.4±7.3)%], all these effects were diminished or inhibited by BQ123, SB203580 or LY294002. Furthermore, the effects of BQ123 and SB203580 on decreased gel contraction were stronger than the effect of LY294002. CONCLUSION: ET-1 exerts a key role in the airway fibroblasts activation induced by injured HBE through activating p38 MAPK, PI3K/Akt signaling and promoting IL-6 expression.