PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-25 (958681)

Clipboard (0)
None

Related Articles

1.  Matrix metalloproteinases -8, -9 and -12 in smokers and patients with Stage 0 COPD 
COPD is underdiagnosed and its early assessment is problematic. It has been suggested that symptomatic smokers with normal FEV1/FVC (Stage 0 COPD, GOLD criteria) can develop COPD in the future. Potential early biomarkers in COPD include the matrix metallo-proteinases (MMPs). It is not yet known, whether alterations in MMP expression are associated with smoking alone or with the risk of developing COPD. In this cross-sectional study MMP-8, MMP-9 and MMP-12 were determined from induced sputum and plasma by ELISA, immunocytochemistry, zymography, and/or Western blot in non-smokers (n = 32), smokers with symptoms (Stage 0, GOLD criteria) (n = 23) or without symptoms (n = 23). Only MMP-8 differentiated Stage 0 COPD from non-symptomatic smokers (p = 0.02). MMP-9 levels were significantly elevated in the induced sputum of non-symptomatic smokers and Stage 0 COPD (p = 0.01, p < 0.001) compared to non-smokers, but did not differ between the two subgroups of smokers. MMP-12 was higher only at Stage 0 compared to non-smokers (p = 0.04). MMP-8, MMP-9 and MMP-12 immunoreactivity was localized in macrophages and neutrophils, especially in smokers. MMP-8 levels correlated significantly with the small airway flow parameters (MEF50, MEF25) (p = 0.005 and p = 0.0004) and markers of neutrophil activation (myeloperoxidase, lactoferrin). In conclusion MMP-8 may differentiate Stage 0 from healthy smokers.
PMCID: PMC2695187  PMID: 18229576
cigarette smoking; GOLD; COPD; MMP; myeloperoxidase; oxidant; Stage 0
2.  Patterns of airway inflammation and MMP-12 expression in smokers and ex-smokers with COPD 
Respiratory Research  2007;8(1):81.
Background
Smoking activates and recruits inflammatory cells and proteases to the airways. Matrix metalloproteinase (MMP)-12 may be a key mediator in smoke induced emphysema. However, the influence of smoking and its cessation on airway inflammation and MMP-12 expression during COPD is still unknown. We aimed to analyse airway inflammatory cell patterns in induced sputum (IS) and bronchoalveolar lavage (BAL) from COPD patients who are active smokers and who have ceased smoking >2 years ago.
Methods
39 COPD outpatients – smokers (n = 22) and ex-smokers (n = 17) were studied. 8 'healthy' smokers and 11 healthy never-smokers were tested as the control groups. IS and BAL samples were obtained for differential and MMP-12+-macrophages count analysis.
Results
The number of IS neutrophils was higher in both COPD groups compared to both controls. The amount of BAL neutrophils was higher in COPD smokers compared to healthy never-smokers. The number of BAL MMP-12+-macrophages was higher in COPD smokers (1.6 ± 0.3 × 106/ml) compared to COPD ex-smokers, 'healthy' smokers and healthy never-smokers (0.9 ± 0.4, 0.4 ± 0.2, 0.2 ± 0.1 × 106/ml respectively, p < 0.05).
Conclusion
The lower amount of BAL neutrophils in COPD ex-smokers, compared to COPD smokers, suggests positive alterations in alveolar compartment after smoking cessation. Smoking and disease itself may stimulate MMP-12 expression in airway compartments (IS and BAL) from COPD patients.
doi:10.1186/1465-9921-8-81
PMCID: PMC2200652  PMID: 18001475
3.  Analysis of Sputum Markers in the Evaluation of Lung Inflammation and Functional Impairment in Symptomatic Smokers and COPD Patients 
Disease markers  2011;31(2):91-100.
The pivotal role of neutrophils and macrophages in smoking-related lung inflammation and COPD development is well-established.
We aimed to assess whether sputum concentrations of Human Neutrophil Peptides (HNP), Neutrophil Elastase (NE), Interleukin-8 (IL-8), and Metalloproteinase-9 (MMP-9), major products of neutrophils and macrophages, could be used to trace airway inflammation and progression towards pulmonary functional impairment characteristic of COPD.
Forty-two symptomatic smokers and 42 COPD patients underwent pulmonary function tests; sputum samples were collected at enrolment, and 6 months after smoking cessation.
HNP, NE, IL-8, MMP-9 levels were increased in individuals with COPD (p < 0.0001). HNP and NE concentrations were higher in patients with severe airways obstruction, as compared to patients with mild-to-moderate COPD (p = 0.002). A negative correlation was observed between FEV1 and HNP, NE and IL-8 levels (p < 0.01), between FVC1/FVC and HNP, NE and IL-8 levels (p < 0.01), and between NE enrolment levels and FEV1 decline after 2 years (p = 0.04).
ROC analysis, to discriminate symptomatic smokers and COPD patients, showed the following AUCs: for HNP 0.92; for NE 0.81; for IL-8 0.89; for MMP-9 0.81; for HNP, IL-8 and MMP-9 considered together 0.981.
The data suggest that the measurement of sputum markers may have an important role in clinical practice for monitoring COPD.
doi:10.3233/DMA-2011-0807
PMCID: PMC3826390  PMID: 21897003
Airway inflammation; Chronic obstructive pulmonary disease; neutrophil elastase; human neutrophil peptides; interleukin-8; likelihood ratio; metalloproteinase-9; sputum; receiver operating characteristic analysis; smoking
4.  Association between markers of emphysema and more severe chronic obstructive pulmonary disease 
Thorax  2006;61(12):1037-1042.
Background
The predominant emphysema phenotype is associated with more severe airflow limitation in patients with chronic obstructive pulmonary disease (COPD). A study was undertaken to investigate whether COPD patients, with or without emphysema quantitatively confirmed by high resolution computed tomography (HRCT), have different COPD severity as assessed by the BODE index (body mass index, airflow obstruction, dyspnoea, exercise performance) and inspiratory capacity to total lung capacity ratio (IC/TLC), and by different biological markers of lung parenchymal destruction.
Methods
Twenty six outpatients with COPD and eight healthy non‐smokers were examined. Each subject underwent HRCT scanning, pulmonary function tests, cell counts, and measurements of neutrophil elastase, matrix metalloproteinase (MMP)‐9 and tissue inhibitor of metalloproteinase (TIMP)‐1 in induced sputum, as well as measurement of desmosine, a marker of elastin degradation in urine, plasma and sputum.
Results
Patients with HRCT confirmed emphysema had a higher BODE index and lower IC/TLC ratio than subjects without HRCT confirmed emphysema and controls. Forced expiratory volume in 1 second (FEV1), FEV1/forced vital capacity ratio, and carbon monoxide transfer coefficient were lower, whereas the number of eosinophils, MMP‐9, and the MMP‐9/TIMP‐1 ratio in sputum were higher in patients with emphysema. In COPD patients the number of sputum eosinophils was the biological variable that correlated positively with the HRCT score of emphysema (p = 0.04).
Conclusions
These results suggest that COPD associated with HRCT confirmed emphysema is characterised by more severe lung function impairment, more intense airway inflammation and, possibly, more serious systemic dysfunction than COPD not associated with HRCT confirmed emphysema.
doi:10.1136/thx.2006.058321
PMCID: PMC2117071  PMID: 16769715
chronic obstructive pulmonary disease; emphysema; biological markers; outcomes
5.  Lung matrix metalloproteinase-9 correlates with cigarette smoking and obstruction of airflow. 
Journal of Korean Medical Science  2003;18(6):821-827.
Cigarette smoking is the most important risk factor for obstruction of airflow in chronic obstructive pulmonary disease (COPD). Matrix metalloproteinases (MMPs) or an imbalance between MMPs and their inhibitors, the tissue inhibitors of MMP (TIMPs), is considered to play a role in the pathogenesis of COPD. We investigated whether the MMPs expression or the imbalance between MMPs and TIMP-1 is associated with the amount of cigarette smoking and the FEV1 value, in the lung parenchyma of 26 subjects (6 non-smokers and 20 cigarette smokers). First, we performed zymographic analysis to identify the profile of the MMPs, which revealed gelatinolytic bands mainly equivalent to MMP-9 in the smokers. We then measured, using enzyme immunoassay, the concentrations of MMP-9 and its inhibitor, TIMP-1. Correlation analysis revealed that both the MMP-9 concentrations and the molar ratios of MMP-9 to TIMP-1 (MMP-9/TIMP-1) were correlated with the amount of cigarette smoking. Furthermore, MMP-9 concentrations were inversely correlated with FEV1. In conclusion, this study shows that MMP-9 expression in human lung parenchyma is associated with cigarette smoking and also with the obstruction of airflow, suggesting that MMP-9 may play a role in the pathogenesis of the cigarette smoke-induced obstruction of airflow known as the characteristic of COPD.
PMCID: PMC3055149  PMID: 14676438
6.  Cigarette Smoke Stimulates Matrix Metalloproteinase-2 Activity via EGR-1 in Human Lung Fibroblasts 
Cigarette smoking is a major risk factor for chronic obstructive pulmonary disease (COPD). Recent reports of increased matrix metalloproteinase-2 (MMP-2) in lungs of patients with emphysema support the paradigm of proteinase/antiproteinase imbalance in the pathogenesis of COPD. We sought to define the signaling pathways activated by smoke and to identify molecules responsible for emphysema-associated MMP-2 expression. In this study, we show that cigarette smoke extract (CSE) induced MMP-2 protein expression and increased MMP-2 gelatinase activity of normal lung fibroblasts. We previously identified a transcription factor, early growth response 1 (EGR-1), with robust expression in the lung tissues of patients with COPD compared with control smokers. Here, the treatment of fibroblasts with CSE resulted in marked induction of EGR-1 mRNA and protein in a dose- and time-dependent manner, accompanied by increased EGR-1 binding activity. CSE-induced MMP-2 mRNA and protein expression and activity were significantly inhibited using EGR-1 small interfering RNA (siRNA) or in Egr-1–null−/− mouse fibroblasts. Furthermore, we observed induction of membrane type 1 matrix metalloproteinase (MT1-MMP), which has an EGR-1–binding site on its promoter, in CSE-treated primary normal lung fibroblasts. The concomitant MT1-MMP expression and MMP-2 activation by CSE are inhibited by EGR-1 siRNA. Rapid activation of mitogen-activated protein kinases was observed in CSE-treated fibroblasts. Chemical inhibitors of ERK1/2 MAPK, but not of p38 and JNK, decreased CSE-induced EGR-1 protein expression and MMP-2 activity of fibroblasts. The identification that induction of MMP-2 and MT1-MMP by CSE from lung fibroblasts is EGR-1–dependent reveals a molecular mechanism for matrix remodeling in cigarette smoke–related emphysema.
doi:10.1165/rcmb.2006-0106OC
PMCID: PMC1899323  PMID: 17099140
chronic obstructive pulmonary disease; EGR-1; cigarette smoke extract; MMP-2; MT1-MMP
7.  Matrix Metalloproteinase-14 Mediates a Phenotypic Shift in the Airways to Increase Mucin Production 
Rationale: Induced mainly by cigarette smoking, chronic obstructive pulmonary disease (COPD) is a global public health problem characterized by progressive difficulty in breathing and increased mucin production. Previously, we reported that acrolein levels found in COPD sputum could activate matrix metalloproteinase-9 (MMP9).
Objectives: To determine whether acrolein increases expression and activity of MMP14, a critical membrane-bound endopeptidase that can initial a MMP-activation cascade.
Methods: MMP14 activity and adduct formation were measured following direct acrolein treatment. MMP14 expression and activity was measured in human airway epithelial cells. MMP14 immunohistochemistry was performed with COPD tissue, and in acrolein- or tobacco-exposed mice.
Measurements and Main Results: In a cell-free system, acrolein, in concentrations equal to those found in COPD sputum, directly adducted cysteine 319 in the MMP14 hemopexin-like domain and activated MMP14. In cells, acrolein increased MMP14 activity, which was inhibited by a proprotein convertase inhibitor, hexa-d-arginine. In the airway epithelium of COPD subjects, immunoreactive MMP14 protein increased. In mouse lung, acrolein or tobacco smoke increased lung MMP14 activity and protein. In cells, acrolein-induced MMP14 transcripts were inhibited by an epidermal growth factor receptor (EGFR) neutralizing antibody, EGFR kinase inhibitor, metalloproteinase inhibitor, or mitogen-activated protein kinase (MAPK) 3/2 or MAPK8 inhibitors, but not a MAPK14 inhibitor. Decreasing the MMP14 protein and activity in vitro by small interfering (si)RNA to MMP14 diminished the acrolein-induced MUC5AC transcripts. In acrolein-exposed mice or transgenic mice with lung-specific transforming growth factor-α (an EGFR ligand) expression, lung MMP14 and MUC5AC levels increased and these effects were inhibited by a EGFR inhibitor, erlotinib.
Conclusions: Taken together, these findings implicate acrolein-induced MMP14 expression and activity in mucin production in COPD.
doi:10.1164/rccm.200903-0328OC
PMCID: PMC2773913  PMID: 19661247
cigarette smoke; acrolein; erlotinib; mucous cell metaplasia; chronic obstructive pulmonary disease
8.  Discovery of Emphysema Relevant Molecular Networks from an A/J Mouse Inhalation Study Using Reverse Engineering and Forward Simulation (REFS™) 
Chronic obstructive pulmonary disease (COPD) is a respiratory disorder caused by extended exposure of the airways to noxious stimuli, principally cigarette smoke (CS). The mechanisms through which COPD develops are not fully understood, though it is believed that the disease process includes a genetic component, as not all smokers develop COPD. To investigate the mechanisms that lead to the development of COPD/emphysema, we measured whole genome gene expression and several COPD-relevant biological endpoints in mouse lung tissue after exposure to two CS doses for various lengths of time. A novel and powerful method, Reverse Engineering and Forward Simulation (REFS™), was employed to identify key molecular drivers by integrating the gene expression data and four measured COPD-relevant endpoints (matrix metalloproteinase (MMP) activity, MMP-9 levels, tissue inhibitor of metalloproteinase-1 levels and lung weight). An ensemble of molecular networks was generated using REFS™, and simulations showed that it could successfully recover the measured experimental data for gene expression and COPD-relevant endpoints. The ensemble of networks was then employed to simulate thousands of in silico gene knockdown experiments. Thirty-three molecular key drivers for the above four COPD-relevant endpoints were therefore identified, with the majority shown to be enriched in inflammation and COPD.
doi:10.4137/GRSB.S13140
PMCID: PMC3937248  PMID: 24596455
Bayesian network; chronic obstructive pulmonary disease (COPD); reverse engineering and forward simulation (REFS™)
9.  Tumor necrosis factor-α serum levels in healthy smokers and nonsmokers 
Background:
Tobacco smoking is the most important risk factor for chronic obstructive pulmonary disease (COPD) development. Inhaled cigarette smoke can induce tumor necrosis factor-α (TNF-α) production by alveolar macrophages, which in turn may enhance the production of metalloproteinases (MMPs). MMPs have been involved in mediating airway inflammation and lung destruction.
Objectives:
We aimed to measure the TNF-α serum levels in healthy heavy smokers and healthy nonsmokers to determine the dose-response relationship based on the cigarette smoke exposure.
Subjects and methods:
We included in our study 43 healthy heavy smokers and 19 healthy nonsmokers (the control group). The smokers group was classified as less than one pack, one pack, and more than one pack per day. A clinical and paraclinical evaluation was performed in both groups, without any evidence of infection or COPD. The serum levels of TNF-α were assessed by ELISA.
Results:
The TNF-α serum levels were significantly higher for the group of smokers compared to the group of nonsmokers (P < 0.004). We also noticed an increased TNF-α concentration in the serum of smokers with more than one pack per day compared with those with less than one pack per day (P < 0.03). There was a positive correlation between the serum level of TNF-α and tobacco smoke exposure.
Conclusions:
The high levels of TNF-α in the serum of smokers suggest an imbalance between the proinflammatory and anti-inflammatory factors as a result of tobacco smoke exposure. The concentration of TNF-α is elevated in the serum of healthy heavy smokers in a cigarette dose-dependent manner. We speculate that the serum level of TNF-α might be a useful biomarker for the selection of heavy smokers with a high risk of developing smoke induced pulmonary diseases.
PMCID: PMC2921689  PMID: 20714375
tobacco smoking; inflammation; chronic obstructive pulmonary disease; metalloproteinases
10.  Inducible targeting of IL-13 to the adult lung causes matrix metalloproteinase– and cathepsin-dependent emphysema 
Journal of Clinical Investigation  2000;106(9):1081-1093.
Cigarette smoke exposure is the major cause of chronic obstructive pulmonary disease (COPD). However, only a minority of smokers develop significant COPD, and patients with asthma or asthma-like airway hyperresponsiveness or eosinophilia experience accelerated loss of lung function after cigarette smoke exposure. Pulmonary inflammation is a characteristic feature of lungs from patients with COPD. Surprisingly, the mediators of this inflammation and their contributions to the pathogenesis and varied natural history of COPD are not well defined. Here we show that IL-13, a critical cytokine in asthma, causes emphysema with enhanced lung volumes and compliance, mucus metaplasia, and inflammation, when inducibly overexpressed in the adult murine lung. MMP-2, -9, -12, -13, and -14 and cathepsins B, S, L, H, and K were induced by IL-13 in this setting. In addition, treatment with MMP or cysteine proteinase antagonists significantly decreased the emphysema and inflammation, but not the mucus in these animals. These studies demonstrate that IL-13 is a potent stimulator of MMP and cathepsin-based proteolytic pathways in the lung. They also demonstrate that IL-13 causes emphysema via a MMP- and cathepsin-dependent mechanism(s) and highlight common mechanisms that may underlie COPD and asthma.
PMCID: PMC301418  PMID: 11067861
11.  FEV1 inversely correlates with metalloproteinases 1, 7, 9 and CRP in COPD by biomass smoke exposure 
Respiratory Research  2014;15(1):74.
Background
Matrix metalloproteinases (MMPs) and C-reactive protein (CRP) are involved in chronic obstructive pulmonary disease (COPD) pathogenesis. The aim of the present work was to determine plasma concentrations of MMPs and CRP in COPD associated to biomass combustion exposure (BE) and tobacco smoking (TS).
Methods
Pulmonary function tests, plasma levels of MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP were measured in COPD associated to BE (n = 40) and TS (n =40) patients, and healthy non-smoking (NS) healthy women (controls, n = 40).
Results
Plasma levels of MMP-1, MMP-7, MMP-9, and MMP-9/TIMP-1 and CRP were higher in BE and TS than in the NS healthy women (p <0.01). An inverse correlation between MMP-1, MMP-7, MMP-9, MMP-9/TIMP-1 and CRP plasma concentrations and FEV1 was observed.
Conclusions
Increase of MMPs and CRP plasma concentrations in BE suggests a systemic inflammatory phenomenon similar to that observed in COPD associated to tobacco smoking, which may also play a role in COPD pathogenesis.
doi:10.1186/1465-9921-15-74
PMCID: PMC4086695  PMID: 24980707
Biomass combustion exposure; C-reactive protein; Chronic obstructive pulmonary disease; FEV1; Metalloproteinases; Tobacco smoking
12.  Simvastatin inhibits induction of matrix metalloproteinase-9 in rat alveolar macrophages exposed to cigarette smoke extract 
Experimental & Molecular Medicine  2009;41(4):277-287.
Matrix metalloproteinase-9 (MMP-9) may play an important role in emphysematous change in chronic obstructive pulmonary disease (COPD), one of the leading causes of mortality and morbidity worldwide. We previously reported that simvastatin, an inhibitor of HMG-CoA reductase, attenuates emphysematous change and MMP-9 induction in the lungs of rats exposed to cigarette smoke. However, it remained uncertain how cigarette smoke induced MMP-9 and how simvastatin inhibited cigarette smoke-induced MMP-9 expression in alveolar macrophages (AMs), a major source of MMP-9 in the lungs of COPD patients. Presently, we examined the related signaling for MMP-9 induction and the inhibitory mechanism of simvastatin on MMP-9 induction in AMs exposed to cigarette smoke extract (CSE). In isolated rat AMs, CSE induced MMP-9 expression and phosphorylation of ERK and Akt. A chemical inhibitor of MEK1/2 or PI3K reduced phosphorylation of ERK or Akt, respectively, and also inhibited CSE-mediated MMP-9 induction. Simvastatin reduced CSE-mediated MMP-9 induction, and simvastatin-mediated inhibition was reversed by farnesyl pyrophosphate (FPP) or geranylgeranyl pyrophosphate (GGPP). Similar to simvastatin, inhibition of FPP transferase or GGPP transferase suppressed CSE-mediated MMP-9 induction. Simvastatin attenuated CSE-mediated activation of RAS and phosphorylation of ERK, Akt, p65, IκB, and nuclear AP-1 or NF-κB activity. Taken together, these results suggest that simvastatin may inhibit CSE-mediated MMP-9 induction, primarily by blocking prenylation of RAS in the signaling pathways, in which Raf-MEK-ERK, PI3K/Akt, AP-1, and IκB-NF-κB are involved.
doi:10.3858/emm.2009.41.4.031
PMCID: PMC2679231  PMID: 19299917
macrophages, alveolar; matrix metalloproteinases-9; pulmonary disease, chronic obstructive; pulmonary emphysema; simvastatin; smoking
13.  Influence of Age, Past Smoking, and Disease Severity on TLR2, Neutrophilic Inflammation, and MMP-9 Levels in COPD 
Mediators of Inflammation  2013;2013:462934.
Chronic obstructive pulmonary disease (COPD) is a common and serious respiratory disease, particularly in older individuals, characterised by fixed airway obstruction and persistent airway neutrophilia. The mechanisms that lead to these features are not well established. We investigated the contribution of age, prior smoking, and fixed airflow obstruction on sputum neutrophils, TLR2 expression, and markers of neutrophilic inflammation. Induced sputum from adults with COPD (n = 69) and healthy controls (n = 51) was examined. A sputum portion was dispersed, total, differential cell count and viability recorded, and supernatant assayed for CXCL8, matrix metalloproteinase- (MMP-) 9, neutrophil elastase, and soluble TLR2. Peripheral blood cells (n = 7) were stimulated and TLR2 activation examined. TLR2 levels were increased with ageing, while sputum neutrophils and total sputum MMP-9 levels increased with age, previous smoking, and COPD. In multivariate regression, TLR2 gene expression and MMP-9 levels were significant independent contributors to the proportion of sputum neutrophils after adjustment for age, prior smoking, and the presence of airflow obstruction. TLR2 stimulation led to enhanced release of MMP-9 from peripheral blood granulocytes. TLR2 stimulation activates neutrophils for MMP-9 release. Efforts to understand the mechanisms of TLR2 signalling and subsequent MMP-9 production in COPD may assist in understanding neutrophilic inflammation in COPD.
doi:10.1155/2013/462934
PMCID: PMC3628212  PMID: 23606791
14.  Vascular endothelial growth factor: an angiogenic factor reflecting airway inflammation in healthy smokers and in patients with bronchitis type of chronic obstructive pulmonary disease? 
Respiratory Research  2007;8(1):53.
Background
Patients with bronchitis type of chronic obstructive pulmonary disease (COPD) have raised vascular endothelial growth factor (VEGF) levels in induced sputum. This has been associated with the pathogenesis of COPD through apoptotic and oxidative stress mechanisms. Since, chronic airway inflammation is an important pathological feature of COPD mainly initiated by cigarette smoking, aim of this study was to assess smoking as a potential cause of raised airway VEGF levels in bronchitis type COPD and to test the association between VEGF levels in induced sputum and airway inflammation in these patients.
Methods
14 current smokers with bronchitis type COPD, 17 asymptomatic current smokers with normal spirometry and 16 non-smokers were included in the study. VEGF, IL-8, and TNF-α levels in induced sputum were measured and the correlations between these markers, as well as between VEGF levels and pulmonary function were assessed.
Results
The median concentrations of VEGF, IL-8, and TNF-α were significantly higher in induced sputum of COPD patients (1,070 pg/ml, 5.6 ng/ml and 50 pg/ml, respectively) compared to nonsmokers (260 pg/ml, 0.73 ng/ml, and 15.4 pg/ml, respectively, p < 0.05) and asymptomatic smokers (421 pg/ml, 1.27 ng/ml, p < 0.05, and 18.6 pg/ml, p > 0.05, respectively). Significant correlations were found between VEGF levels and pack years (r = 0.56, p = 0.046), IL-8 (r = 0.64, p = 0.026) and TNF-α (r = 0.62, p = 0.031) levels both in asymptomatic and COPD smokers (r = 0.66, p = 0.027, r = 0.67, p = 0.023, and r = 0.82, p = 0.002, respectively). No correlation was found between VEGF levels in sputum and pulmonary function parameters.
Conclusion
VEGF levels are raised in the airways of both asymptomatic and COPD smokers. The close correlation observed between VEGF levels in the airways and markers of airway inflammation in healthy smokers and in smokers with bronchitis type of COPD is suggestive of VEGF as a marker reflecting the inflammatory process that occurs in smoking subjects without alveolar destruction.
doi:10.1186/1465-9921-8-53
PMCID: PMC1939848  PMID: 17631682
15.  Elevation of sputum matrix metalloproteinase-9 persists up to 6 months after smoking cessation: a research study 
Background
Smoking cessation is the best possible way to prevent the progression of smoking related airway diseases. However, the effect and time scale of smoking cessation on airway inflammation/remodelling are largely unknown. This prospective study evaluated the effects of smoking cessation on induced sputum (IS) neutrophils, matrix metalloproteinases (MMP-7, -8, -9) and tissue inhibitor of metalloproteinase-1 (TIMP-1).
Methods
A total of 61 subjects participated in the study; 17 stopped smoking for 3 months and 9 for 6 months. The proportion of IS neutrophils and the levels of MMPs and TIMP-1 by ELISA were determined at baseline and at 3 and 6 months after cessation.
Results
In the smokers, baseline IS neutrophils, MMPs and TIMP-1 were significantly higher compared to non-smokers. Levels of MMP-7, -8 and TIMP-1 decreased nearly to those of non-smokers but the levels of MMP-9 increased significantly from the baseline of the same subjects at 3 months after cessation (p = 0.009) with no significant decline at 6 months after cessation.
Conclusions
Sputum MMP-9 remained elevated after 6 months of smoking cessation, which may contribute to ongoing lung damage typical of COPD.
doi:10.1186/1471-2466-10-13
PMCID: PMC2841651  PMID: 20226090
16.  Ageing and smoking contribute to plasma surfactant proteins and protease imbalance with correlations to airway obstruction 
Background
A significant number of young people start smoking at an age of 13-15, which means that serious smoking-evoked changes may have been occurred by their twenties. Surfactant proteins (SP) and matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) have been linked to cigarette smoke induced lung remodelling and chronic obstructive pulmonary disease (COPD). However, the level of these proteins has not been examined during ageing or in young individuals with short smoking histories.
Methods
Plasma levels of SP-A, SP-D, MMP-9, and TIMP-1 were measured by EIA/ELISA from young (18-23 years) non-smoking controls (YNS) (n = 36), smokers (YS) (n = 51), middle aged/elderly (37-77 years) non-smoking controls (ONS) (n = 40), smokers (OS) (n = 64) (FEV1/FVC >0.7 in all subjects) and patients with COPD (n = 44, 35-79 years).
Results
Plasma levels of SP-A increased with age and in the older group in relation to smoking and COPD. Plasma SP-D and MMP-9 levels did not change with age but were elevated in OS and COPD as compared to ONS. The TIMP-1 level declined with age but increased in chronic smokers when compared to ONS. The clearest correlations could be detected between plasma SP-A vs. age, pack years and FEV1/FVC. The receiver operating characteristic (ROC) curve analysis revealed SP-A to be the best marker for discriminating between patients with COPD and the controls (area under ROC curve of 0.842; 95% confidence interval, 0.785-0.899; p < 0.001).
Conclusions
Age has a significant contribution to potential markers related to smoking and COPD; SP-A seems to be the best factor in differentiating COPD from the controls.
doi:10.1186/1471-2466-11-19
PMCID: PMC3103485  PMID: 21504569
17.  Glutathione and nitrite levels in induced sputum at COPD patients and healthy smokers 
Journal of Thoracic Disease  2014;6(6):765-771.
Objectives
The role of oxidative stress at the pathogenesis of chronic obstructive pulmonary disease (COPD) is known. The aim of this study is to investigate the oxidative stress with sputum induction that is a simple method in COPD patients and healthy smokers.
Methods
Sputum induction was performed in 21 COPD patients (10 stable, 11 acute exacerbations), nine healthy smokers, and ten healthy non-smokers. Glutathione, NO2– levels, and cell counts at sputum, and plasma NO2– contents were evaluated in all subjects.
Results
Mean sputum glutathione and NO2– levels were significantly higher in acute exacerbations with COPD patients than healthy smokers (P=0.007 and P<0.001 respectively), and non-smokers (P<0.001 and P<0.001 respectively). On the other hand, sputum glutathione and NO2– levels did not show significant differences between stable and acute exacerbations with COPD patients. Although, sputum glutathione levels were higher in stable COPD patients than healthy smokers’, no statistically significant difference was established. In addition, sputum glutathione levels were significantly higher in healthy smokers than non-smokers (P<0.001).
Conclusions
As a result, we can say that oxidative stress increases not only in COPD patients but also in healthy smokers. In addition, sputum induction that is a simple method can be used to demonstrate to show oxidative stress.
doi:10.3978/j.issn.2072-1439.2014.04.24
PMCID: PMC4073373  PMID: 24977001
Glutathione; nitrite; induced sputum; chronic obstructive pulmonary disease (COPD)
18.  Analysis of aberrant methylation on promoter sequences of tumor suppressor genes and total DNA in sputum samples: a promising tool for early detection of COPD and lung cancer in smokers 
Diagnostic Pathology  2012;7:87.
Background
Chronic obstructive pulmonary disease (COPD) is a disorder associated to cigarette smoke and lung cancer (LC). Since epigenetic changes in oncogenes and tumor suppressor genes (TSGs) are clearly important in the development of LC. In this study, we hypothesize that tobacco smokers are susceptible for methylation in the promoter region of TSGs in airway epithelial cells when compared with non-smoker subjects. The purpose of this study was to investigate the usefulness of detection of genes promoter methylation in sputum specimens, as a complementary tool to identify LC biomarkers among smokers with early COPD.
Methods
We determined the amount of DNA in induced sputum from patients with COPD (n = 23), LC (n = 26), as well as in healthy subjects (CTR) (n = 33), using a commercial kit for DNA purification, followed by absorbance measurement at 260 nm. The frequency of CDKN2A, CDH1 and MGMT promoter methylation in the same groups was determined by methylation-specific polymerase chain reaction (MSP). The Fisher’s exact test was employed to compare frequency of results between different groups.
Results
DNA concentration was 7.4 and 5.8 times higher in LC and COPD compared to the (CTR) (p < 0.0001), respectively. Methylation status of CDKN2A and MGMT was significantly higher in COPD and LC patients compared with CTR group (p < 0.0001). Frequency of CDH1 methylation only showed a statistically significant difference between LC patients and CTR group (p < 0.05).
Conclusions
We provide evidence that aberrant methylation of TSGs in samples of induced sputum is a useful tool for early diagnostic of lung diseases (LC and COPD) in smoker subjects.
Virtual slides
The abstract MUST finish with the following text: Virtual Slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1127865005664160
doi:10.1186/1746-1596-7-87
PMCID: PMC3424112  PMID: 22818553
DNA methylation; Sputum; Lung cancer; COPD
19.  Optimization of total protein and activity assays for the detection of MMP-12 in induced human sputum 
Background
Proteolysis of matrix components, in particular elastin, is a major contributing factor to the development of lung diseases such as emphysema and chronic obstructive pulmonary disease (COPD). MMP-12 (macrophage elastase) is a protease known to be involved in the progression of lung disease. The relatively low abundance of MMP-12 has precluded the development of quantitative assays that can accurately measure MMP-12 protein levels and activity across cohorts of healthy and diseased individuals.
Methods
Commercial antibodies were screened for performance in sandwich ELISA and capture FRET activity assay formats. Precision, accuracy, sensitivity, dilution linearity, and spike recovery were evaluated using sputum samples.
Results
Total protein and capture FRET activity assays were developed that were sensitive enough to detect MMP-12 in 37 of 38 donor sputum samples. A comparison of results between the two assays shows that a majority of sputum MMP-12 is in the active form. No differences were seen between normal, asthmatic, and COPD donors.
Conclusion
Sensitive and quantitative assays for both MMP-12 activity and total protein in human induced sputum have been developed. These assays can be used to evaluate MMP-12 as a biomarker for lung disease, and to monitor efficacy of potential therapeutic compounds.
doi:10.1186/1471-2466-10-40
PMCID: PMC2921351  PMID: 20678199
20.  Impact of smoking on dendritic cell phenotypes in the airway lumen of patients with COPD 
Respiratory Research  2014;15(1):48.
Background
Myeloid dendritic cells (DCs) are increased in the airway wall of patients with chronic obstructive pulmonary disease (COPD), and postulated to play a crucial role in COPD. However, DC phenotypes in COPD are poorly understood.
Methods
Function-associated surface molecules on bronchoalveolar lavage fluid (BALF) DCs were analyzed using flow cytometry in current smokers with COPD, in former smokers with COPD and in never-smoking controls.
Results
Myeloid DCs of current smokers with COPD displayed a significantly increased expression of receptors for antigen recognition such as BDCA-1 or Langerin, as compared with never-smoking controls. In contrast, former smokers with COPD displayed a significantly decreased expression of these receptors, as compared with never-smoking controls. A significantly reduced expression of the maturation marker CD83 on myeloid DCs was found in current smokers with COPD, but not in former smokers with COPD. The chemokine receptor CCR5 on myeloid DCs, which is also important for the uptake and procession of microbial antigens, was strongly reduced in all patients with COPD, independently of the smoking status.
Conclusion
COPD is characterized by a strongly reduced CCR5 expression on myeloid DCs in the airway lumen, which might hamper DC interactions with microbial antigens. Further studies are needed to better understand the role of CCR5 in the pathophysiology and microbiology of COPD.
doi:10.1186/1465-9921-15-48
PMCID: PMC4021430  PMID: 24742278
Dendritic cells; COPD; Smoking; Airway
21.  Markers of nitric oxide metabolism in sputum and exhaled air are not increased in chronic obstructive pulmonary disease 
Thorax  1999;54(7):576-580.
BACKGROUND—Nitric oxide (NO) is involved in inflammation and host defence of the lung. It has been found in increased concentrations in the airways in asthmatic subjects but its levels in patients with chronic obstructive pulmonary disease (COPD) have not been investigated. A study was undertaken to determine whether markers of NO metabolism (NO in exhaled air, iNOS expression in sputum cells, and nitrite + nitrate (NO2-/NO3-) in sputum supernatant) are increased in subjects with COPD, and whether they correlate with inflammatory indices in induced sputum. The associations of these markers with smoking were also assessed.
METHODS—Sixteen subjects with COPD (median age 66 years, median forced expiratory volume in one second (FEV1) 63% predicted, eight current smokers) and 16 healthy subjects (median age 63 years, median FEV1 113% predicted, eight current smokers) participated in the study. NO was measured during tidal breathing and sputum was induced by inhalation of hypertonic saline.
RESULTS—No differences were observed between subjects with COPD and healthy controls in exhaled NO excretion rate (median 5.15 and 6.25 nmol/min), sputum macrophage iNOS expression (14% and 12%), and sputum supernatant NO2-/NO3- (46 and 73 µM). NO in exhaled air correlated with the percentage of sputum eosinophils in patients with COPD (rho = 0.65, p = 0.009) but not in healthy individuals. Exhaled NO and supernatant NO2-/NO3- levels were lower in healthy smokers than in healthy non/ex-smokers.
CONCLUSIONS—Our findings indicate that NO metabolism is not increased in patients with stable COPD. The close association between exhaled NO levels and sputum eosinophils suggests a role for NO in airway inflammation in COPD. Studies performed during exacerbations may clarify this role.


PMCID: PMC1745531  PMID: 10377200
22.  Persistence of oxidant and protease burden in the airways after smoking cessation 
Background
Oxidative stress is associated with the pathogenesis of cigarette smoke related lung diseases, but longitudinal effects of smoking cessation on oxidant markers in the airways are unknown.
Methods
This study included 61 smokers; 21 with chronic bronchitis or COPD, 15 asthmatics and 25 asymptomatic smokers followed up for 3 months after smoking cessation. Fractional exhaled nitric oxide (FeNO), sputum neutrophil counts, sputum 8-isoprostane, nitrotyrosine and matrix metalloproteinase-8 (MMP-8) were investigated at baseline and 1 and 3 months after smoking cessation.
Results
After 3 months 15 subjects had succeeded in quitting of smoking and in these subjects symptoms improved significantly. Unexpectedly, however, sputum neutrophils increased (p = 0.046) after smoking cessation in patients with chronic bronchitis/COPD. At baseline, the other markers did not differ between the three groups so these results were combined for further analysis. Sputum 8-isoprostane declined significantly during the follow-up at 3 months (p = 0.035), but levels still remained significantly higher than in non-smokers. The levels of FeNO, nitrotyrosine and MMP-8 did not change significantly during the 3 months after smoking cessation.
Conclusion
Whilst symptoms improve after smoking cessation, the oxidant and protease burden in the airways continues for months.
doi:10.1186/1471-2466-9-25
PMCID: PMC2697135  PMID: 19473482
23.  The Role of Circulating Serotonin in the Development of Chronic Obstructive Pulmonary Disease 
PLoS ONE  2012;7(2):e31617.
Background
Cigarette smoking is a major risk factor in the development of age-related chronic obstructive pulmonary disease (COPD). The serotonin transporter (SERT) gene polymorphism has been reported to be associated with COPD, and the degree of cigarette smoking has been shown to be a significant mediator in this relationship. The interrelation between circulating serotonin (5-hydroxytyptamine, 5-HT), cigarette smoking and COPD is however largely unknown. The current study aimed at investigating the mediation effects of plasma 5-HT on cigarette smoking-induced COPD and the relation between plasma 5-HT levels and age.
Methods
The association between plasma 5-HT, age and COPD was analyzed in a total of 62 COPD patients (ever-smokers) and 117 control subjects (healthy non-smokers and ever-smokers). Plasma 5-HT levels were measured by enzyme-linked immuno assay (EIA).
Results
The elevated plasma 5-HT levels were significantly associated with increased odds for COPD (OR = 1.221, 95% CI = 1.123 to 1.319, p<0.0001). The effect remained significant after being adjusted for age and pack-years smoked (OR = 1.271, 95% CI = 1.134 to 1.408, p = 0.0003). Furthermore, plasma 5-HT was found to mediate the relation between pack-years smoked and COPD. A positive correlation (r = 0.303, p = 0.017) was found between plasma 5-HT levels and age in COPD, but not in the control subjects (r = −0.149, p = 0.108).
Conclusion
Our results suggest that cigarette smoke-induced COPD is partially mediated by the plasma levels of 5-HT, and that these become elevated with increased age in COPD. The elevated plasma 5-HT levels in COPD might contribute to the pathogenesis of this disease.
doi:10.1371/journal.pone.0031617
PMCID: PMC3272036  PMID: 22319639
24.  Increased Matrix Metalloproteinase (MMPs) Levels Do Not Predict Disease Severity or Progression in Emphysema 
PLoS ONE  2013;8(2):e56352.
Rationale
Though matrix metalloproteinases (MMPs) are critical in the pathogenesis of COPD, their utility as a disease biomarker remains uncertain. This study aimed to determine whether bronchoalveolar lavage (BALF) or plasma MMP measurements correlated with disease severity or functional decline in emphysema.
Methods
Enzyme-linked immunosorbent assay and luminex assays measured MMP-1, -9, -12 and tissue inhibitor of matrix metalloproteinase-1 in the BALF and plasma of non-smokers, smokers with normal lung function and moderate-to-severe emphysema subjects. In the cohort of 101 emphysema subjects correlative analyses were done to determine if MMP or TIMP-1 levels were associated with key disease parameters or change in lung function over an 18-month time period.
Main Results
Compared to non-smoking controls, MMP and TIMP-1 BALF levels were significantly elevated in the emphysema cohort. Though MMP-1 was elevated in both the normal smoker and emphysema groups, collagenase activity was only increased in the emphysema subjects. In contrast to BALF, plasma MMP-9 and TIMP-1 levels were actually decreased in the emphysema cohort compared to the control groups. Both in the BALF and plasma, MMP and TIMP-1 measurements in the emphysema subjects did not correlate with important disease parameters and were not predictive of subsequent functional decline.
Conclusions
MMPs are altered in the BALF and plasma of emphysema; however, the changes in MMPs correlate poorly with parameters of disease intensity or progression. Though MMPs are pivotal in the pathogenesis of COPD, these findings suggest that measuring MMPs will have limited utility as a prognostic marker in this disease.
doi:10.1371/journal.pone.0056352
PMCID: PMC3575373  PMID: 23441181
25.  Matrix-metalloproteinase 12 Overexpression in Lung Epithelial Cells Plays a Key Role in Emphysema to Lung Bronchioalveolar Adenocarcinoma Transition 
Cancer research  2009;69(18):7252-7261.
Chronic obstructive pulmonary disease (COPD) and lung cancer are two diseases that are related to smoking in humans. The molecular mechanism linking these two diseases is poorly understood. Matrix metalloproteinase 12 (MMP12) is a member of the matrix-metalloproteinase family, which can be induced by smoking. Since MMP12 overexpression in epithelial cells has been reported in inflammation-triggered lung remodeling, a murine CCSP-rtTA/(tetO)7-MMP12 bitransgenic model was created. In this model, MMP12-Flag fusion protein overexpression and its increased enzymatic activity were observed in the lung in an inducible manner, which led to inflammatory cell infiltration and increased epithelial growth. In sequential events, spontaneous emphysema and bronchioalveolar adenocarcinoma were developed as a result of MMP12 overexpression. During this process, the concentration of IL-6 was steadily increased in bronchioalveolar lavage fluid, which activated the oncogenic Stat3 in alveolar type II epithelial cells. Expression of Stat3 downstream genes that are knownto stimulate inflammation and tumor formation was significantly increased in the lung. When tested in humans, MMP12 up-regulation was highly associated with COPD and lung cancer in patients. Together, these studies support that MMP12 is a potent pro-inflammatory and oncogenic molecule. MMP12 up-regulation plays a critical role in emphysema to lung cancer transition that is facilitated by pulmonary inflammation.
doi:10.1158/0008-5472.CAN-09-0577
PMCID: PMC2753283  PMID: 19706765

Results 1-25 (958681)