Airway Inflammation In COPD Research Articles

The Effect of Secondhand Smoke Exposure on Bronchus Airway Inflammation in COPD

The Effect of Secondhand Smoke Exposure on Bronchus Airway Inflammation in COPD

Baicalin Relieves Airway Inflammation in COPD by Inhibiting miR-125a.

To investigate the effects of Baicalin on the apoptosis of human bronchial epithelial cells (16HBE) induced by cigarette smoke extract (CSE) and the release of inflammatory factors, and to clarify its possible mechanism. CSE was used to treat 16HBE cells and construct COPD cell model. The activity of 16HBE cells was detected by CCK-8 and BrdU. Real-time fluorescence quantitative PCR (RT-QPCR) was used to detect the expression level of miR-125a in each group of 16HBE cells. At the same time, the levels of 16HBE inflammatory cytokines IL-1β, IL-8, IL-6, and TNF-α were detected. The apoptosis rate of 16HBE cells in each group was detected by TUNEL. Compared with the control group, the proliferation of 16HBE cells in CSE group was decreased. Baicalin reversed the effect of 2% CSE on the proliferation of 16HBE cells. Baicalin also reversed the effect of 2% CSE on apoptosis and inflammatory factors in 16HBE cells. miR-125a is highly expressed in COPD, and Baicalin can inhibit the expression of miR-125a. Silencing miR-125a reduces apoptosis and inflammatory response of 16HBE cells in COPD. miR-125a reversed the effects of Baicalin on apoptosis and inflammation of 16HBE cells. Baicalin can reduce CSE-induced apoptosis of human bronchial epithelial cells and release of inflammatory factors, and its mechanism may be related to the inhibition of miR-125a.

Novel Anti-Inflammatory Approaches to COPD.

Airway inflammation, driven by different types of inflammatory cells and mediators, plays a fundamental role in COPD and its progression. Neutrophils, eosinophils, macrophages, and CD4+ and CD8+ T lymphocytes are key players in this process, although the extent of their participation varies according to the patient's endotype. Anti-inflammatory medications may modify the natural history and progression of COPD. However, since airway inflammation in COPD is relatively resistant to corticosteroid therapy, innovative pharmacological anti-inflammatory approaches are required. The heterogeneity of inflammatory cells and mediators in annethe different COPD endo-phenotypes requires the development of specific pharmacologic agents. Indeed, over the past two decades, several mechanisms that influence the influx and/or activity of inflammatory cells in the airways and lung parenchyma have been identified. Several of these molecules have been tested in vitro models and in vivo in laboratory animals, but only a few have been studied in humans. Although early studies have not been encouraging, useful information emerged suggesting that some of these agents may need to be further tested in specific subgroups of patients, hopefully leading to a more personalized approach to treating COPD.

Longitudinal Effects of 1-Year Smoking Cessation on Human Bronchial Epithelial Transcriptome

Longitudinal Effects of 1-Year Smoking Cessation on Human Bronchial Epithelial Transcriptome

Extracellular vesicles isolated from hyperuricemia patients might aggravate airway inflammation of COPD via senescence-associated pathway

BackgroundsChronic obstructive pulmonary disease (COPD) is a major health issue resulting in significant mortality worldwide. Due to the high heterogeneity and unclear pathogenesis, the management and therapy of COPD are still challenging until now. Elevated serum uric acid(SUA) levels seem to be associated with the inflammatory level in patients with COPD. However, the underlying mechanism is not yet clearly established. In the current research, we aim to elucidate the effect of high SUA levels on airway inflammation among COPD patients.MethodsThrough bioinformatic analysis, the common potential key genes were determined in both COPD and hyperuricemia (HUA) patients. A total of 68 COPD patients aged 50—75-year were included in the study, and their clinical parameters, including baseline characteristics, lung function test, as well as blood chemistry test were recorded. These parameters were then compared between the COPD patients with and without HUA. Hematoxylin & Eosin (HE), immunofluorescence (IF), and Masson trichrome staining were performed to demonstrate the pathological changes in the lung tissues. Furthermore, we isolated extracellular vesicles (EVs) from plasma, sputum, and bronchoalveolar lavage fluid (BALF) samples and detected the expression of inflammatory factor (Interleukin-6 (IL-6), IL-8 and COPD related proteases (antitrypsin and elastase) between two groups. Additionally, we treated the human bronchial epithelial (HBE) cells with cigarette smoke extract (CSE), and EVs were derived from the plasma in vitro experiments. The critical pathway involving the relationship between COPD and HUA was eventually validated based on the results of RNA sequencing (RNA-seq) and western blot (WB).ResultsIn the study, the COPD patients co-existing with HUA were found to have more loss of pulmonary function compared with those COPD patients without HUA. The lung tissue samples of patients who had co-existing COPD and HUA indicated greater inflammatory cell infiltration, more severe airway destruction and even fibrosis. Furthermore, the high SUA level could exacerbate the progress of airway inflammation in COPD through the transfer of EVs. In vitro experiments, we determined that EVs isolated from plasma, sputum, and BALF played pivotal roles in the CSE-induced inflammation of HBE. The EVs in HUA patients might exacerbate both systemic inflammation and airway inflammatory response via the senescence-related pathway.ConclusionThe pulmonary function and clinical indicators of COPD patients with HUA were worse than those without HUA, which may be caused by the increased airway inflammatory response through the EVs in the patient's peripheral blood. Moreover, it might mediate the EVs via senescence-related pathways in COPD patients with HUA.

MiR-155 contribute to airway inflammation in COPD by regulating autophagy via targeting TLR4/NF-ΚB

To evaluate the expression of miR-155 and autophagy in COPD and the related mechanism. Alveolar macrophages were extracted from COPD patients. COPD dynamic mouse model was established. Mouse alveolar macrophages were also isolated and cultured. Rat alveolar macrophage cell line NR8383 was introduced. The expression of TLR4 and NF-κB in NR8383 cells with CSE treatment was also evaluated. miR-155 was upregulated in alveolar macrophages from bronchoalveolar lavage fluid of COPD patients, COPD dynamic mouse model and CSE treated NR8383 cell line (p < 0.05). Overexpression of miR‐155 led to dysregulation of cell autophagy and was closely. miR‐155 promoted cell autophagy by directly targeting TLR4/NF-κB pathway in NR8383 cell line. Our study revealed a novel inflammatory role of miR-155 in COPD and the related mechanisms. We provide a new perspective to understand the pathogenesis of COPD, and miR-155 might be useful as potential target for the treatment of COPD.

Airway inflammation in COPD: Is it worth measuring and is it clinically meaningful?

See related Article

Dysregulation of the endothelial nitric oxide pathway is associated with airway inflammation in COPD

BackgroundChronic obstructive pulmonary disease (COPD) is related to endothelial dysfunction and the impaired generation of nitric oxide (NO) from L-arginine by the endothelial NO synthase (eNOS). The relationship between eNOS dysfunctionality and airway inflammation is unknown. We assessed serum asymmetric and symmetric dimethylarginine (ADMA and SDMA) and nitrite/nitrate concentrations, indicators of eNOS function, in patients with COPD and correlated them with markers of inflammation.MethodsWe recruited 15 control smokers, 29 patients with stable and 32 patients with exacerbated COPD requiring hospitalization (20 of them were measured both at admission and discharge). Serum L-arginine, ADMA, SDMA, nitrite and nitrate were measured and correlated with airway inflammatory markers (fractional exhaled nitric oxide concentration - FENO, sputum nitrite and nitrate, sputum cellularity), serum C-reactive protein - CRP, white blood cell count, lung function and blood gases. ANOVA, t-tests and Pearson correlation were used (mean ± SD or geometric mean ± geometric SD for nitrite/nitrate).ResultsSerum L-arginine/ADMA, a marker of substrate availability for eNOS, was lower in stable (214 ± 58, p < 0.01) and exacerbated COPD (231 ± 68, p < 0.05) than in controls (287 ± 64). The serum concentration of SDMA, a competitor of L-arginine transport, was elevated during an exacerbation (0.78 ± 0.39 μM) compared to stable patients (0.53 ± 0.14 μM, p < 0.01) and controls (0.45 ± 0.14 μM, p < 0.001). ADMA correlated with blood neutrophil percentage (r = 0.36, p < 0.01), FENO (r = 0.42, p < 0.01) and a tendency for positive association was observed to sputum neutrophil count (r = 0.33, p = 0.07). SDMA correlated with total sputum inflammatory cell count (r = 0.61, p < 0.01) and sputum neutrophil count (r = 0.62, p < 0.01). Markers were not related to lung function, blood gases or CRP. L-arginine/ADMA was unchanged, but serum SDMA level decreased (0.57 ± 0.42 μM, p < 0.05) after systemic steroid treatment of the exacerbation. Serum nitrite level increased in stable and exacerbated disease (4.11 ± 2.12 and 4.03 ± 1.77 vs. control: 1.61 ± 1.84 μM, both p < 0.001).ConclusionsOur data suggest impaired eNOS function in stable COPD, which is transiently aggravated during an exacerbation and partly reversed by systemic steroid treatment. Serum ADMA and SDMA correlate with airway inflammatory markers implying a possible effect of anti-inflammatory therapy on endothelial dysfunction. Serum nitrite can serve as a compensatory pool for impaired endothelial NO generation.

Do blood eosinophils strictly reflect airway inflammation in COPD? Comparison with asthmatic patients

IntroductionAirway eosinophilic inflammation is a characteristic of asthmatic patients and of a sub group of COPD subjects. Blood eosinophils are deemed as a good surrogate marker of sputum eosinophilic inflammation; however, controversial data have been published particularly in COPD. The aim of our study was to compare blood and sputum eosinophils in COPD and asthmatic patients in “real life”.MethodsSputum was induced in stable patients with COPD or asthma with hypertonic saline solution and blood eosinophils were evaluated. Frequency of comorbidities was recorded. Correlations were performed stratifying patients by disease and comorbidities.Results146 patients, 57 with COPD and 89 with asthma were evaluated. Blood and sputum eosinophils expressed as percentages were correlated in COPD (rho = 0.40; p = 0.004), but the entity of correlation was lower compared with asthmatic subjects (rho = 0.71; p < 0.0001). When blood eosinophils were expressed as counts the correlation was slightly lower than when expressed as percentages in COPD (rho = 0.35; p = 0.01) and in asthmatic patients (rho = 0.68; p < 0.0001). In COPD patients older than 73 years or with blood eosinophils higher than the median value (210.6 eos/μl), or co-diagnosed with hypertension, ischemic heart disease or atrial fibrillation no correlation between blood and sputum eosinophils was found.However, the effect of ischemic heart disease and atrial fibrillation could be driven by hypertension since most of these patients have this comorbidity.ConclusionBlood eosinophils correlated with sputum eosinophils to a lesser degree in COPD than in asthmatic patients. Older age, high blood eosinophils and hypertension affected the correlation between blood and sputum eosinophils, more studies are needed to evaluate the role of other cardiac comobidities.

Effects of bronchodilation on biomarkers of peripheral airway inflammation in COPD

Peripheral airway inflammation and dysfunction are key elements in the pathogenesis of COPD. The exhaled alveolar fraction of nitric oxide (CANO) is an indirect biomarker of lung peripheral inflammation. We tested whether inhaled long-acting bronchodilators (LABA) can affect CANO and we evaluated correlations with lung mechanics in patients with COPD.Two-centre, randomised, double blind, crossover study including COPD patients with moderate-to-severe airflow obstruction. Following a pharmacological washout, multi-flow exhaled fraction of NO (FENO), plethysmography, lung diffusion (DLCO), single breath nitrogen washout test and dyspnoea were measured in a crossover manner at baseline and 30, 60 and 180 min following administration of salmeterol (Sal) or formoterol fumarate (FF). (ClinicalTrials.gov, number NCT01853787).Fort-five patients were enrolled (median age: 71.8 years; 84.4% males). At baseline, CANO correlated with airway resistances (r = 0.422), residual volume/total lung capacity (RV/TLC; r = 0.375), transfer factor (r= -0.463) and forced expiratory volume in 1 s (FEV1; r= -0.375, all P < 0.01). After LABA administration, we found a significant reduction of FENO that reached statistical significance at 180’; no difference was found between FF and S. Consistently, a significant reduction of CANO was documented at 60’ and 180’ compared to baseline for both FF and S (P < 0.01 and P < 0.05, respectively). Changes in CANO were correlated with changes in vital capacity (r=-44; P < 0.001) and RV/TLC (r = 0.56; P < 0.001), but not FEV1.In COPD, direct correlations were found between the levels of CANO and the magnitude of peripheral airway dysfunction. LABA reduced CANO levels. The reduction was associated with improvement in functional parameters reflecting air trapping.

Post-bronchodilator Reversibility of FEV1 and Eosinophilic Airway Inflammation in COPD

IntroductionThe relationship between bronchodilator responsiveness and eosinophilic airway inflammation has not been well documented in COPD. It has been investigated in this retrospective study. This issue has grown in importance due to increasing interest in the asthma-COPD overlap syndrome. Methods264 stable COPD patients with no past history of asthma were retrospectively analyzed. Correlation analyses between FEV1 reversibility and sputum eosinophil levels were conducted. Sputum eosinophil levels were dichotomized using FEV1 reversibility cut-off points (>0.4L and >15% vs. >0.2L and >12%) and compared. The effectiveness of FEV1 reversibility to predict sputum eosinophilia (>3%) was analyzed with a logistic regression and a ROC analysis. Results82 (31.1%) patients with higher FEV1 reversibility values (0.14 vs. 0.11L, P=.01) presented sputum eosinophilia. FEV1 reversibility was weakly correlated with the sputum eosinophil level (r=0.162, P=.008). Patients with FEV1>0.4L and >15% increment had higher sputum eosinophil levels (6.11 vs. 1.02%, P=.049) whereas the level did not differ when dichotomized by FEV1 increment >0.2L and >12%. Very positive FEV1 reversibility (>0.4L and >15%) predicted sputum eosinophilia after adjustment forage, baseline FEV1 and FVC (OR: 4.262, P=.029). In the ROC analysis, the AUC was 0.58 (P=.034), and FEV1 increment>0.4L and >15% had a positive predictive value of 63.6% and an overall accuracy of 70.1%. ConclusionsFEV1 reversibility was weakly correlated with sputum eosinophil levels in COPD. Positive FEV1 reversibility (>0.4L and >15%) is moderately successful in predicting sputum eosinophilia (>3%).

Post-bronchodilator Reversibility of FEV1 and Eosinophilic Airway Inflammation in COPD

IntroductionThe relationship between bronchodilator responsiveness and eosinophilic airway inflammation has not been well documented in COPD. It has been investigated in this retrospective study. This issue has grown in importance due to increasing interest in the asthma-COPD overlap syndrome. Methods264 stable COPD patients with no past history of asthma were retrospectively analyzed. Correlation analyses between FEV1 reversibility and sputum eosinophil levels were conducted. Sputum eosinophil levels were dichotomized using FEV1 reversibility cut-off points (>0.4L and >15% vs. >0.2L and >12%) and compared. The effectiveness of FEV1 reversibility to predict sputum eosinophilia (>3%) was analyzed with a logistic regression and a ROC analysis. Results82 (31.1%) patients with higher FEV1 reversibility values (0.14 vs. 0.11L, P=.01) presented sputum eosinophilia. FEV1 reversibility was weakly correlated with the sputum eosinophil level (r=0.162, P=.008). Patients with FEV1>0.4L and >15% increment had higher sputum eosinophil levels (6.11 vs. 1.02%, P=.049) whereas the level did not differ when dichotomized by FEV1 increment >0.2L and >12%. Very positive FEV1 reversibility (>0.4L and >15%) predicted sputum eosinophilia after adjustment forage, baseline FEV1 and FVC (OR: 4.262, P=.029). In the ROC analysis, the AUC was 0.58 (P=.034), and FEV1 increment>0.4L and >15% had a positive predictive value of 63.6% and an overall accuracy of 70.1%. ConclusionsFEV1 reversibility was weakly correlated with sputum eosinophil levels in COPD. Positive FEV1 reversibility (>0.4L and >15%) is moderately successful in predicting sputum eosinophilia (>3%).

Serum IL-1β and IL-17 levels in patients with COPD: associations with clinical parameters.

COPD is a chronic airway inflammatory disease characterized mainly by neutrophil airway infiltrations. Interleukin (IL)-1β and IL-17 are the key mediators of neutrophilic airway inflammation in COPD. This study was undertaken to evaluate the serum IL-1β and IL-17 levels and associations between these two key mediators with clinical parameters in COPD patients. Serum samples were collected from 60 COPD subjects during the acute exacerbation of COPD, 60 subjects with stable COPD and 40 healthy control subjects. Commercial enzyme-linked immunosorbent assay kits were used to measure the serum IL-1β and IL-17 concentrations. The association between serum IL-1β and IL-17 with FEV1% predicted, C-reactive protein, neutrophil percentage and smoking status (pack-years) was assessed in the COPD patients. We found that serum IL-1β and IL-17 levels in acute exacerbation of COPD subjects were significantly higher than that in stable COPD or control subjects and were positively correlated to serum C-reactive protein levels, neutrophil % and smoking status (pack-years) but negatively correlated with FEV1% predicted in COPD patients. More importantly, serum IL-1β levels were markedly positively associated with serum IL-17 levels in patients with COPD (P=0.741, P<0.001). In conclusion, elevated serum IL-1β and IL-17 levels may be used as a biomarker for indicating persistent neutrophilic airway inflammation and potential ongoing exacerbation of COPD.

Relationships between Mucosal Antibodies, Non-Typeable Haemophilus influenzae (NTHi) Infection and Airway Inflammation in COPD.

Non-typeable Haemophilus influenzae (NTHi) is a key pathogen in COPD, being associated with airway inflammation and risk of exacerbation. Why some patients are susceptible to colonisation is not understood. We hypothesised that this susceptibility may be due to a deficiency in mucosal humoral immunity. The aim of our study (NCT01701869) was to quantify the amount and specificity of antibodies against NTHi in the lungs and the associated risk of infection and inflammation in health and COPD. Phlebotomy, sputum induction and bronchoscopy were performed on 24 mild-to-moderate COPD patients and 8 age and smoking-matched controls. BAL (Bronchoalveolar lavage) total IgG1, IgG2, IgG3, IgM and IgA concentrations were significantly increased in COPD patients compared to controls. NTHi was detected in the lungs of 7 of the COPD patients (NTHi+ve—29%) and these patients had a higher median number of previous exacerbations than NTHi-ve patients as well as evidence of increased systemic inflammation. When comparing NTHi+ve versus NTHi-ve patients we observed a decrease in the amount of both total IgG1 (p = 0.0068) and NTHi-specific IgG1 (p = 0.0433) in the BAL of NTHi+ve patients, but no differences in total IgA or IgM. We observed no evidence of decreased IgG1 in the serum of NTHi+ve patients, suggesting this phenomenon is restricted to the airway. Furthermore, the NTHi+ve patients had significantly greater levels of IL-1β (p = 0.0003), in BAL than NTHi-ve COPD patients.This study indicates that the presence of NTHi is associated with reduced levels and function of IgG1 in the airway of NTHi-colonised COPD patients. This decrease in total and NTHI-specific IgG1 was associated with greater systemic and airway inflammation and a history of more frequent exacerbations and may explain the susceptibility of some COPD patients to the impacts of NTHi.

A pro-inflammatory role for the Frizzled-8 receptor in chronic bronchitis

RationaleWe have previously shown increased expression of the Frizzled-8 receptor of the Wingless/integrase-1 (WNT) signalling pathway in COPD. Here, we investigated if the Frizzled-8 receptor has a functional role in...

Anti-Inflammatory Effects of Lactobacillus Rahmnosus and Bifidobacterium Breve on Cigarette Smoke Activated Human Macrophages.

BackgroundChronic obstructive pulmonary disease (COPD) is a major global health problem with cigarette smoke (CS) as the main risk factor for its development. Airway inflammation in COPD involves the increased expression of inflammatory mediators such as CXCL-8 and IL-1β which are important mediators for neutrophil recruitment. Macrophages are an important source of these mediators in COPD. Lactobacillus rhamnosus (L. rhamnosus) and Befidobacterium breve (B. breve) attenuate the development of ‘allergic asthma’ in animals but their effects in COPD are unknown.ObjectiveTo determine the anti-inflammatory effects of L. rhamnosus and B. breve on CS and Toll-like receptor (TLR) activation.DesignWe stimulated the human macrophage cell line THP-1 with CS extract in the presence and absence of L. rhamnosus and B. breve and measured the expression and release of inflammatory mediators by RT-qPCR and ELISA respectively. An activity assay and Western blotting were used to examine NF-κB activation.ResultsBoth L. rhamnosus and B. breve were efficiently phagocytized by human macrophages. L. rhamnosus and B. breve significantly suppressed the ability of CS to induce the expression of IL-1β, IL-6, IL-10, IL-23, TNFα, CXCL-8 and HMGB1 release (all p<0.05) in human THP-1 macrophages. Similar suppression of TLR4- and TLR9-induced CXCL8 expression was also observed (p<0.05). The effect of L. rhamnosus and B. breve on inflammatory mediator release was associated with the suppression of CS-induced NF-κB activation (p<0.05).ConclusionsThis data indicate that these probiotics may be useful anti-inflammatory agents in CS-associated disease such as COPD.

Supplementing Defect in Club Cell Secretory Protein Attenuates Airway Inflammation in COPD

Club cell secretory protein (CCSP) is a protective biomarker associated with annual decline in lung function. COPD progression results from an imbalance between injury and repair initially triggered by cigarette smoking. We investigated the effect of CCSP as a therapeutic strategy to restore the balance between injury and repair in COPD simultaneously, validating an ex vivo air-liquid interface (ALI) culture of human bronchial epithelial cells. Endobronchial biopsy specimens (EBBs) were obtained from 13 patients with COPD, eight smokers, and eight control subjects. Morphometric analysis of the initial EBBs was performed. ALI cultures derived from the same EBBs were exposed to cigarette smoke extract (CSE) with or without exogenous recombinant human CCSP (rhCCSP) supplementation. CCSP and IL-8 concentrations were assessed at steady state and after CSE exposure. Morphometric analysis of the initial EBBs showed increased cell density but decreased immunostaining of CCSP+ cells in EBBs of patients with COPD (P = .03 vs control subjects). At steady state, lower CCSP (P = .04) and higher IL-8 levels (P < .0001) were found in COPD ALI epithelium. Exogenous rhCCSP supplementation dampened CSE-induced IL-8-release in patients with COPD and returned to levels similar to those of smokers and control subjects (P = .0001). A negative correlation was found between IL-8-release in ALI and CCSP+ cell density in initial biopsy specimens (P = .0073). In vitro, rhCCSP exogenous supplementation can reverse CSE-induced IL-8 release in biopsy specimens from patients with COPD, indicating a potential use of this strategy in vivo.

Bronchial hyperresponsiveness, airway inflammation, and reversibility in patients with chronic obstructive pulmonary disease.

BackgroundBronchial hyperresponsiveness (BHR), sputum eosinophilia, and bronchial reversibility are often thought to be a hallmark of asthma, yet it has been shown to occur in COPD as well.ObjectivesTo evaluate the relationship between BHR, lung function, and airway inflammation in COPD patients.MethodsThirty-one, steroid-free patients with stable, mild and moderate COPD were studied. The following tests were carried out: baseline lung function, reversibility, provocative dose of methacholine causing a 20% fall in forced expiratory volume in 1 second, a COPD symptom score, and sputum induction.ResultsTwenty-nine patients completed the procedures. About 41.4% had BHR, 31.0% had increased sputum eosinophils, and 37.9% had bronchial reversibility. Some of the patients had only one of these characteristics while others had two or the three of them. Patients with BHR had higher sputum eosinophils than patients without BHR (P=0.046) and those with sputum eosinophils ≥3% had more exacerbations in the previous year and a higher COPD symptom score than patients with sputum eosinophils <3% (P=0.019 and P=0.031, respectively). In patients with BHR, the cumulative dose of methacholine was negatively related to the symptom score and the number of exacerbations in the previous year. When patients with bronchial reversibility were considered, bronchodilation was positively related to sputum eosinophils.ConclusionOur study showed that BHR, sputum eosinophilia, and bronchial reversibility were not clustered in one single phenotype of COPD but could be present alone or together. Of interest, BHR and airway eosinophilia were associated with clinical data in terms of exacerbations and symptoms. Further investigation is needed to clarify this topic.

Association Between Pathogens Detected Using Quantitative Polymerase Chain Reaction With Airway Inflammation in COPD at Stable State and Exacerbations

BACKGROUND:Relationships between airway inflammation and respiratory potentially pathogenic microorganisms (PPMs) quantified using quantitative polymerase chain reaction (qPCR) in subjects with COPD are unclear. Our aim was to evaluate mediators of airway inflammation and their association with PPMs in subjects with COPD at stable state and during exacerbations.METHODS:Sputum from 120 stable subjects with COPD was analyzed for bacteriology (colony-forming units; total 16S; and qPCR targeting Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae), differential cell counts, and inflammatory mediators using the Meso-Scale Discovery Platform. Subjects were classified as colonized if any PPM was identified above the threshold of detection by qPCR. Symptoms were quantified using the visual analog scale.RESULTS:At stable state, 60% of subjects were qPCR positive for H influenzae, 48% for M catarrhalis, and 28% for S pneumoniae. Elevated sputum concentrations of IL-1β, IL-10, and tumor necrosis factor (TNF)-α were detected in samples qPCR positive for either H influenzae or M catarrhalis. Bacterial loads of H influenzae positively correlated with IL-1β, IL-8, IL-10, TNF-α, and symptoms; and M catarrhalis correlated with IL-10 and TNF-α. H influenzae qPCR bacterial load was an independent predictor of sputum TNF-α and IL-1β. In 55 subjects with paired exacerbation data, qPCR bacterial load fold change at exacerbation in M catarrhalis but not H influenzae correlated to changes in sputum TNF-α and IL-1β concentrations.CONCLUSIONS:At stable state, H influenzae is associated with increased airway inflammation in COPD. The relationship between bacterial load changes of specific pathogens and airway inflammation at exacerbation and recovery warrants further investigation.

Acetylcholine leads to signal transducer and activator of transcription 1 (STAT-1) mediated oxidative/nitrosative stress in human bronchial epithelial cell line

The induction of nitric oxide synthase (iNOS) expression via the signal transducer and activator of transcription 1 (STAT-1) is involved in the mechanism of oxidative/nitrosative stress. We investigated whether acetylcholine (ACh) generates oxidative/nitrosative stress in bronchial epithelial cells during airway inflammation of COPD and evaluated the effects of Tiotropium, a once-daily antimuscarinic drug, and Olodaterol, a long-acting β2-agonist on these mechanisms. Human bronchial epithelial cells (16-HBE) were stimulated (4h, 37°C) with induced sputum supernatants (ISSs) from healthy controls (HC) (n=10), healthy smokers (HS) (n=10) or COPD patients (n=10), as well as with ACh (from 1μM to 100μM). The activation of STAT-1 pathway (STAT-1Ser727 and STAT-1Tyr701) and iNOS was evaluated in the cell lysates by Western blot analysis as well as nitrotyrosine levels by ELISA, while reactive oxygen species (ROS) were evaluated by flow cytometry. Finally, the effect of Tiotropium (Spiriva®) (100nM), alone or in combination with Olodaterol (1nM), was tested in this model. ISSs from COPD patients significantly increased the phosphorylation of STAT-1Ser727 and STAT-1Tyr701, iNOS and ROS/Nitrotyrosine when compared with ISSs from HC or HS subjects in 16-HBE cells. Furthermore, synthetic ACh increased all these parameters in stimulated 16HBE when compared with untreated cells. Tiotropium and Olodaterol reduced the oxidative/nitrosative stress generated by ACh and ISSs. We concluded that ACh mediated the oxidative/nitrosative stress involving the STAT-1 pathway activation in human bronchial epithelial cells during COPD. β2-Long acting and antimuscarinic drugs, normally used in the treatment of COPD as bronchodilator, might be able to control these cellular events.