elastin and Pulmonary-Disease--Chronic-Obstructive

Elastin is an important protein of the extracellular matrix of higher vertebrates, which confers elasticity and resilience to various tissues and organs including lungs, skin, large blood vessels and ligaments. Owing to its unique structure, extensive cross-linking and durability, it does not undergo significant turnover in healthy tissues and has a half-life of more than 70 years. Elastin is not only a structural protein, influencing the architecture and biomechanical properties of the extracellular matrix, but also plays a vital role in various physiological processes. Bioactive elastin peptides termed elastokines - in particular those of the GXXPG motif - occur as a result of proteolytic degradation of elastin and its non-cross-linked precursor tropoelastin and display several biological activities. For instance, they promote angiogenesis or stimulate cell adhesion, chemotaxis, proliferation, protease activation and apoptosis. Elastin-degrading enzymes such as matrix metalloproteinases, serine proteases and cysteine proteases slowly damage elastin over the lifetime of an organism. The destruction of elastin and the biological processes triggered by elastokines favor the development and progression of various pathological conditions including emphysema, chronic obstructive pulmonary disease, atherosclerosis, metabolic syndrome and cancer. This review gives an overview on types of human elastases and their action on human elastin, including the formation, structure and biological activities of elastokines and their role in common biological processes and severe pathological conditions.

Topics: Aging; Animals; Cardiovascular Diseases; Cysteine Proteases; Elastin; Humans; Matrix Metalloproteinases; Neoplasms; Pancreatic Elastase; Pepsin A; Proteolysis; Pulmonary Disease, Chronic Obstructive; Receptors, Cell Surface; Serine Proteases; Tropoelastin

Platelets are essential mediators of inflammation and thrombosis. Chronic obstructive pulmonary disease (COPD) is a heterogeneous multisystem disease, causing significant morbidity and mortality worldwide. Recent evidence suggests that the lung is an important organ for platelet biogenesis. Cigarette smoking has been shown to induce platelet aggregation and decrease the capacity of mitochondrial electron transport system in platelets. Preclinical and clinical studies have suggested that platelets may contribute to the development of COPD through the breakdown of lung elastin by platelet factor 4, platelet activation and formation of platelet aggregates, and modulation of hypoxia signaling pathways. Recent large population studies have produced encouraging results indicating a potential role for aspirin in preventing exacerbations and delaying disease progression in patients with COPD. This review summarizes the information about the lung as an organ for platelet production, pathophysiological functions of platelets and platelet mediators in the development of COPD, and the most updated evidence on the utility of aspirin in patients with COPD.

Topics: Aspirin; Blood Platelets; Disease Progression; Elastin; Electron Transport; Humans; Inflammation; Lung; Megakaryocytes; Mitochondria; Mitochondrial Diseases; Platelet Activation; Platelet Aggregation; Platelet Aggregation Inhibitors; Platelet Factor 4; Pulmonary Disease, Chronic Obstructive; Smoking; Thrombosis

Current pharmacologic therapy of chronic obstructive pulmonary disease (COPD) can reduce respiratory symptoms and exacerbation frequency. However, no single COPD intervention except for lung transplantation has proven effective in recovering lung function. Lung elasticity is reduced in COPD lungs, which is for a large part due to chronically enhanced elastin degradation. Elastin calcification and formation of advanced glycation end products (AGEs) may also contribute to this. Areas covered: We propose inhalation therapy to induce repair of damaged pulmonary elastin fibers by stimulating tropoelastin synthesis, assembly and crosslinking in order to improve lung function in patients with COPD. Decelerating elastinolysis is another treatment objective, as well as decalcification and deglycation of the extracellular matrix. Expert commentary: Studies should be conducted to test whether it is feasible to restore pulmonary elastin fibers with inhalation therapy. We expect that the optimal formulation will turn out to be a combination of copper, epigallocatechin-(3-)gallate or pentagalloyl glucose, vitamin A/D/K, magnesium, heparin or heparan sulfate, minoxidil and one or more AGEs inhibitors. Establishing a treatment that has the proven ability to facilitate regain of lost lung function in COPD patients would cause a major paradigm shift in this debilitating disease.

Topics: Elastin; Humans; Lung; Pulmonary Disease, Chronic Obstructive; Respiratory Therapy

Biomarkers of pathogenesis in chronic obstructive pulmonary disease (COPD) can significantly accelerate drug development. In COPD related to alpha-1 antitrypsin deficiency, the role of neutrophil elastase and its inhibition by alpha-1 antitrypsin protein focused interest on elastin degradation and the development of pulmonary emphysema. Amino acids desmosine and isodesmosine are unique cross-links in mature elastin fibers and can serve as biomarkers of elastin degradation when measured in body fluids. This review gives a perspective on what has been learned by the earliest measurements of desmosine and isodesmosine followed by later studies using methods of increased sensitivity and specificity and the meaning for developing new therapies. Also included are brief statements on the biomarkers fibrinogen, CC-16, and Aa-Val-360 in COPD.

Topics: alpha 1-Antitrypsin Deficiency; Biomarkers; Desmosine; Elastin; Fibrinogen; Humans; Isodesmosine; Leukocyte Elastase; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Uteroglobin

Why only 20% of smokers develop clinically relevant chronic obstructive pulmonary disease (COPD) was a puzzle for many years. Now, epidemiologic studies point clearly toward a large heritable component. The combination of genome-wide association studies and candidate gene analysis is helping to identify those genetic variants responsible for an individual's susceptibility to developing COPD. In this review, the current data implicating specific loci and genes in the pathogenesis of COPD are examined.

Topics: alpha 1-Antitrypsin; Disease Susceptibility; Elastin; Extracellular Matrix; Genetic Predisposition to Disease; Genome-Wide Association Study; Humans; Mutation; Peptide Hydrolases; Protease Inhibitors; Pulmonary Disease, Chronic Obstructive; Reactive Oxygen Species

Topics: Biomarkers; Bronchodilator Agents; Chromatography, High Pressure Liquid; Desmosine; Disease Progression; Drug Monitoring; Elastin; Humans; Isodesmosine; Pulmonary Disease, Chronic Obstructive; Severity of Illness Index; Tandem Mass Spectrometry

Chronic obstructive pulmonary disease (COPD) is a major health problem worldwide and is now the third leading cause of death in the United States. There is a lack of therapies that can stop progression of the disease and improve survival. New drug discovery can be aided by the development of biomarkers, which can act as indicators of severity in the course of the disease and responses to therapy. This perspective brings together the laboratory and clinical evidence, which suggest that elastin degradation products can fulfill the need for such a biomarker. Elastin is a recognized target for injury in COPD. The amino acids desmosine and isodesmosine exist only in matrix elastin; can be measured specifically and sensitively in plasma, urine, and sputum; and indicate changes in the systemic balance between elastase activity and elastase inhibition brought on by the systemic inflammatory state. The biomarker levels in sputum reflect the state of elastin degradation in the lung specifically. Clinical data accumulated over several decades indicate correlations of desmosine and isodesmosine levels with COPD of varying severity and responses to therapy.

Topics: Biomarkers; Desmosine; Elastin; Humans; Isodesmosine; Lung; Peptide Hydrolases; Pulmonary Disease, Chronic Obstructive; Sputum

Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the US and a major worldwide healthcare problem. The pathophysiologic mechanisms that drive development and progression of this disease are complex and only poorly understood. While tobacco smoking is the primary risk factor, other disease processes also appear to play a role. Components of the innate immune system (eg, macrophages and neutrophils) have long been believed to be important in the development of COPD. More recent evidence also suggests involvement of the adaptive immune system in pathogenesis of this disease. Here we will review the literature supporting the participation of T-cells in the development of COPD, and comment on the potential antigenic stimuli that may account for these responses. We will further explore the prospective contributions of T-cell derived mediators that could contribute to the inflammation, alveolar wall destruction, and small airway fibrosis of advanced COPD. A better understanding of these complex immune processes will lead to new insights that could result in improved preventative and/or treatment strategies.

Topics: Animals; Antigens; Antimicrobial Cationic Peptides; Autoantigens; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Disease Progression; Elastin; Humans; Immunity, Cellular; Inflammation Mediators; Interferon-gamma; Interleukins; Pulmonary Disease, Chronic Obstructive; Smoking; Tumor Necrosis Factor-alpha

Chemoattractant properties of matrix proteins, like collagen and elastin, for neutrophils and monocytes in vitro have long been recognized. This activity often resides in fragments of these proteins. These peptides may play a role in diseases of the lung matrix, such as chronic obstructive pulmonary disease. Recent advances include the elucidation of the structure of chemotactic collagen fragments and the demonstration that their activity may reside in a structural relatedness to CXC chemokines. Collagen and elastin fragments have been demonstrated to have a role in in vivo lung pathophysiology and have been quantified in patients with chronic lung diseases where they may activate autoimmune pathways. Elucidation of these pathways may provide novel biomarkers and therapeutic targets for chronic lung diseases.

Topics: Animals; Chemokines, CXC; Chemotactic Factors; Collagen; Elastin; Extracellular Matrix Proteins; Humans; Inflammation; Lung; Lung Diseases; Matrix Metalloproteinase 9; Oligopeptides; Peptide Fragments; Peptide Hydrolases; Pulmonary Disease, Chronic Obstructive

Fundamental physical properties, such as the intrinsic recoil of the lung, are governed by the extracellular matrix. The prototypical roles of the matrix proteins, collagen and elastin, in pulmonary fibrosis and emphysema have long been recognized, and much research effort has been devoted to understanding mechanisms of extracellular matrix synthesis and turnover in the lung. Yet, despite extensive knowledge of the biochemical properties of collagen and elastin, none of the present clinical strategies for treating COPD directly target the extracellular matrix. From a matrix perspective, therapeutic interventions that limit elastic fiber destruction and/or restore function to damaged alveolar units merit particular consideration as clinical strategies for treating the emphysema component of COPD. Effective treatment of the bronchiolar component of COPD requires a better understanding of the relationship between airway fibrosis and airflow obstruction. Translating basic knowledge of extracellular matrix biology into the clinical venue will be essential in the development of new approaches to COPD treatment.

Topics: Collagen; Elastin; Extracellular Matrix; Humans; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive

Topics: Adenovirus Infections, Human; Antioxidants; Apoptosis; Collagen; DNA Damage; Elastin; Endopeptidases; Humans; Oxidants; Pneumonia; Protease Inhibitors; Protein Denaturation; Pulmonary Disease, Chronic Obstructive; Virus Latency

Cigarette smoking is the major cause of chronic obstructive pulmonary disease (COPD) and it is generally accepted that proteinases released from neutrophils and/or macrophages are involved in the development of emphysema. It remained unknown why only a small portion of smokers develops clinically apparent emphysema and which cells and/or proteinases play a key role in the pathogenesis of COPD. Structural cells in the lungs such as epithelial cells and endothelial cells may also be involved in cell death and repair. Individual genetic background may regulate the function of these cells in response to cigarette smoke and is related to the susceptibility to pulmonary emphysema.

Topics: alpha 1-Antitrypsin; Animals; Aryl Hydrocarbon Hydroxylases; Biodegradation, Environmental; Bronchi; Cytochrome P-450 CYP2A6; Elastin; Epithelial Cells; Extracellular Matrix; Gene Expression Regulation, Enzymologic; Humans; Mixed Function Oxygenases; Pancreatic Elastase; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Smoking

A novel therapy for COPD involving the use of aerosolized hyaluronan (HA) was tested on a small cohort of COPD patients to determine both its safety and efficacy in reducing levels of desmosine and isodesmosine (DID), biomarkers for elastin degradation. In a 2-week, randomized, double-blind trial, 8 patients receiving 150 kDa HA (mean molecular weight) and 3 others given placebo did not show significant adverse effects with regard to spirometry, electrocardiograms, and hematological indices. Furthermore, measurements of DID in plasma from HA-treated patients indicated a progressive decrease over a 3-week period following initiation of treatment (

Topics: Administration, Inhalation; Adult; Aerosols; Aged; Arizona; Biomarkers; Desmosine; Double-Blind Method; Elastin; Humans; Hyaluronic Acid; Isodesmosine; Lung; Middle Aged; New York City; Pilot Projects; Pulmonary Disease, Chronic Obstructive; Sputum; Time Factors; Treatment Outcome

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.. 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.. 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.. 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.

Topics: Antibody Specificity; Calibration; Elastin; Enzyme-Linked Immunosorbent Assay; Fluorescence Resonance Energy Transfer; Humans; Indicator Dilution Techniques; Matrix Metalloproteinase 12; Pulmonary Disease, Chronic Obstructive; Reference Standards; Reproducibility of Results; Sputum

Topics: Asthma; Cross-Sectional Studies; Elastin; Humans; Lung; Pulmonary Disease, Chronic Obstructive; X-Ray Microtomography

To establish a model of emphysema induced by tobacco smoke combined with elastin peptides (EP), explore the biochemical metabolic processes and signal transduction pathways related to emphysema occurrence and development at the transcriptional level, and identify new targets and signaling pathways for emphysema prevention and treatment.. Mice were randomly divided into the air pseudoexposure group (NORMAL group) and the tobacco smoke + EP group (EP group). The differentially expressed genes (DEGs) in lung tissue between the two groups were identified by RNA-seq, and functional annotation and Gene Ontology (GO)/ Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed. The differential expression of the selected genes were verified using qRT‒PCR and immunohistochemistry (IHC).. EP group mice showed emphysema-like changes. The expression levels of 1159 genes in the EP group differed significantly (529 up-regulated and 630 down-regulated) from those in the NORMAL group. GO enrichment analysis showed that the DEGs were significantly enriched in the terms immune system, adaptive immune response, and phosphorylation, while KEGG pathway enrichment analysis showed that the DEGs were enriched mainly in the pathways cytokine‒cytokine receptor interaction, T-cell receptor signaling pathway, MAPK signaling pathway, Rap1 signaling pathway, endocytosis, chemokine signaling pathway, Th17 cell differentiation, and Th1 and Th2 cell differentiation. The differential expression of the selected DEGs were verified by qRT‒PCR and IHC, and the expression trends of these genes were consistent with those identified by RNA-seq.. Emphysema may be related to the inflammatory response, immune response, immune regulation, oxidative stress injury, and other biological processes. The Bmp4-Smad-Hoxa5/Acvr2a signaling pathway may be involved in COPD/ emphysema occurrence and development.

Topics: Animals; Computational Biology; Cytokines; Elastin; Emphysema; Gene Expression Profiling; Mice; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Sequence Analysis, RNA; Tobacco Smoke Pollution; Transcriptome

To investigate the role of the CD40-CD40 ligand (CD40L) pathway in the regulation of Th1, Th17, and regulatory T (Treg)-cell responses in an elastin peptide (EP)-induced autoimmune emphysema mouse model.. BALB/c mice were transnasally treated with EP on day 0, injected intravenously with anti-CD40 antibody via the tail vein on day 33, and sacrificed on day 40. The severity of emphysema was evaluated by determining the mean linear intercept (MLI) and destructive index (DI) from lung sections. The proportions of myeloid dendritic cells (mDCs) and Th1, Th17, and Treg cells in the blood, spleen, and lungs were determined via flow cytometry. The levels of the cytokines interleukin (IL)-6, IL-17, interferon (IFN)-γ, and transforming growth factor (TGF)-β were detected via enzyme-linked immunosorbent assay.. CD40. The CD40-CD40L pathway could play a critical role in Th1, Th17 and Treg cell dysregulation in EP-mediated emphysema and could be a potential therapeutic target.

Topics: Animals; CD40 Antigens; CD40 Ligand; Cytokines; Elastin; Emphysema; Forkhead Transcription Factors; Interleukin-17; Mice; Nuclear Receptor Subfamily 1, Group F, Member 3; Peptides; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Th1 Cells; Th17 Cells

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. The pathogenesis of COPD is complex; however, recent studies suggest autoimmune changes, characterized by the presence of autoantibodies to elastin and collagen, may contribute to disease status. COPD patients make up approximately 30% of all lung transplants (LTx) annually, however, little is known regarding the relationship between COPD-related autoantibodies and LTx outcomes. We hypothesized that COPD patients that undergo LTx and develop primary graft dysfunction (PGD) have altered circulating autoantibody levels and phenotypic changes as compared those COPD-LTx recipients that do not develop PGD. We measured total immunoglobulin and circulating elastin and collagen autoantibody levels in a cohort of COPD lung transplant recipients pre- and post-LTx. No significant differences were seen in total, elastin, or collagen IgM, IgG, IgG1, IgG2, IgG3, and IgG4 antibodies between PGD+ and PGD- recipients. Antibody function can be greatly altered by glycosylation changes to the antibody Fc region and recent studies have reported altered IgG glycosylation profiles in COPD patients. We therefore utilized a novel mass spectrometry-based multiplexed N-glycoprotein imaging approach and measured changes in IgG-specific antibody N-glycan structures. COPD-LTx recipients who developed PGD had significantly increased IgG1 N-glycan signatures as compared PGD- recipients. In conclusion, we show that immunoglobulin and autoreactive antibody levels are not significantly different in COPD LTx recipients that develop PGD. However, using a novel IgG glycomic analysis we were able to demonstrate multiple significant increases in IgG1 specific N-glycan signatures that were predictive of PGD development. Taken together, these data represent a potential novel method for identifying COPD patients at risk for PGD development and may provide clues to mechanisms by which antibody N-glycan signatures could contribute to antibody-mediated PGD pathogenesis.

Topics: Autoantibodies; Elastin; Humans; Immunoglobulin G; Lung Transplantation; Polysaccharides; Primary Graft Dysfunction; Pulmonary Disease, Chronic Obstructive

Emerging evidence indicates that early life events can increase the risk for developing chronic obstructive pulmonary disease (COPD). Using an inducible transgenic mouse model for NF-κB activation in the airway epithelium, we found that a brief period of inflammation during the saccular stage (P3-P5) but not alveolar stage (P10-P12) of lung development disrupted elastic fiber assembly, resulting in permanent reduction in lung function and development of a COPD-like lung phenotype that progressed through 24 months of age. Neutrophil depletion prevented disruption of elastic fiber assembly and restored normal lung development. Mechanistic studies uncovered a role for neutrophil elastase (NE) in downregulating expression of critical elastic fiber assembly components, particularly fibulin-5 and elastin. Further, purified human NE and NE-containing exosomes from tracheal aspirates of premature infants with lung inflammation downregulated elastin and fibulin-5 expression by saccular-stage mouse lung fibroblasts. Together, our studies define a critical developmental window for assembling the elastin scaffold in the distal lung, which is required to support lung structure and function throughout the lifespan. Although neutrophils play a well-recognized role in COPD development in adults, neutrophilic inflammation may also contribute to early-life predisposition to COPD.

Topics: Animals; Elastin; Inflammation; Leukocyte Elastase; Mice; Mice, Transgenic; Neutrophils; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive

Williams-Beuren syndrome (WBS) is caused by an haploinsufficiency of the 7q11.2 region which involves the elastin gene (ELN). A deficiency of elastin is a known pathophysiological mechanism of emphysema/chronic obstructive pulmonary disease (COPD). A previous study hypothesized a higher risk of COPD in WBS patients. Herein, this phenomenon was further investigated looking for a possible correlation between COPD and WBS. Dynamic lung volumes (forced vital capacity [FVC], FEV1, FEV1/FVC) were measured in 22 patients (age range 18.9 ± 7.4 years) affected with WBS, genetically confirmed, correlating these parameters to respiratory risk factors. Dyspnea, cough and wheezing were detected in 6/22 (27%) patients. Obstructive and restrictive patterns were identified in 6/22 (27%) and 2/22 (9%) cases, respectively with no evidence of irreversible obstruction. CVF, FEV1 and FEV1/CVF mean values were all normal, with values of 91.3% (n.v. > 80%), 84.2% (n.v. > 80%) and 0.82 (n.v. > 0.7), respectively. The severity of the comorbidities did not show a cause-effect relation with the respiratory patterns, nevertheless patients treated with anti-hypertensive drugs had poorer pulmonary function. Our findings are in accordance with previous observations, showing that emphysema/COPD is not a typical finding in young patients with WBS. However, a respiratory function assessment should be included in the follow-up of WBS patients, especially in adolescents/young adults under treatment with anti-hypertensive drugs.

Topics: Adolescent; Adult; Child; Elastin; Female; Humans; Italy; Lung; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Respiratory Function Tests; Risk Factors; Spirometry; Vital Capacity; Williams Syndrome; Young Adult

Topics: Dietary Fiber; Elastin; Humans; Pulmonary Disease, Chronic Obstructive

Chronic obstructive pulmonary disease (COPD) is characterized by a slow heterogeneous progression. Therefore, improved biomarkers that can accurately identify patients with the highest likelihood of progression and therefore the ability to benefit from a given treatment, are needed. Elastin is an essential structural protein of the lungs. In this study, we investigated whether elastin degradation products generated by the enzymes proteinase 3, cathepsin G, neutrophil elastase, MMP7 or MMP9/12 were prognostic biomarkers for COPD-related outcomes. The elastin degradome was assessed in a subpopulation (n = 1307) of the Evaluation of COPD Longitudinally to Identify Predictive Surrogate End-points (ECLIPSE) cohort with 3 years of clinical follow-up. Elastin degraded by proteinase 3 could distinguish between COPD participants and non-smoking controls (p = 0.0006). A total of 30 participants (3%) died over the 3 years of observation. After adjusting for confounders, plasma levels of elastin degraded by proteinase 3 and cathepsin G were independently associated with mortality outcome with a hazard ratio per 1 SD of 1.49 (95%CI 1.24-1.80, p < 0.0001) and 1.31 (95%CI 1.10-1.57, p = 0.0029), respectively. Assessing the elastin degradome demonstrated that specific elastin degradation fragments have potential utility as biomarkers identifying subtypes of COPD patients at risk of poor prognosis and supports further exploration in confirmatory studies.

Topics: Biomarkers; Cohort Studies; Disease Progression; Elastin; Female; Humans; Lung; Male; Matrix Metalloproteinase 12; Matrix Metalloproteinase 7; Matrix Metalloproteinase 9; Middle Aged; Myeloblastin; Proportional Hazards Models; Proteolysis; Pulmonary Disease, Chronic Obstructive

Loss of immune tolerance to self-antigens can promote chronic inflammation and disrupt the normal function of multiple organs, including the lungs. Degradation of elastin, a highly insoluble protein and a significant component of the lung structural matrix, generates proinflammatory molecules. Elastin fragments (EFs) have been detected in the serum of smokers with emphysema, and elastin-specific T cells have also been detected in the peripheral blood of smokers with emphysema. However, an animal model that could recapitulate T cell-specific autoimmune responses by initiating and sustaining inflammation in the lungs is lacking. In this study, we report an animal model of autoimmune emphysema mediated by the loss of tolerance to elastin. Mice immunized with a combination of human EFs plus rat EFs but not mouse EFs showed increased infiltration of innate and adaptive immune cells to the lungs and developed emphysema. We cloned and expanded mouse elastin-specific CD4

Topics: Adaptive Immunity; Animals; Autoimmunity; Cell Line; Disease Models, Animal; Elastin; Female; HEK293 Cells; Humans; Immune Tolerance; Immunity, Innate; Inflammation; Lung; Mice; Mice, Inbred C57BL; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Smoking

Insights into the clinical course of COPD indicate the need for new therapies for this condition. The discovery of alpha-1 antitrypsin deficiency (AATD) led to the protease-antiprotease imbalance hypothesis, which was applied to COPD related to AATD as well as COPD not related to AATD. The discovery of AATD brought recognition to the importance of elastin fibers in maintaining lung matrix structure. Two cross-linking amino acids, desmosine and isodesmosine (DI), are unique to mature elastin and can serve as biomarkers of the degradation of elastin. The intravenous augmentation treatment and lung density in severe alpha-1 antitrypsin deficiency (RAPID) study shows a correlation of an anatomic index of COPD (on CT imaging) correlating with a chemical indicator of matrix injury in COPD, DI. The results suggest that preservation of lung elastin structure may slow the progression of COPD. Hyaluronan aerosol decreases the severity of elastase-induced emphysema in animals and has induced reductions in DI levels in preliminary human studies. Hyaluronan deserves further development as a therapy for COPD.

Topics: Adjuvants, Immunologic; Animals; Biomarkers; Clinical Trials as Topic; Desmosine; Disease Models, Animal; Elastin; Glycosaminoglycans; Humans; Hyaluronic Acid; Immunity, Cellular; Isodesmosine; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Rats

This article assesses developments in cardiorespiratory medicine since the Nobel Prize in Physiology or Medicine was awarded in 1956 for advancements in the study of cardiorespiratory disease. In chronic obstructive pulmonary disease, advances were accelerated by the discovery of a genetically determined cause for pulmonary emphysema in the genetic abnormality alpha-1 antitrypsin deficiency. This causes a deficiency of the inhibitor of neutrophil elastase, which results in increased degradation of lung elastin and the development of pulmonary emphysema. This discovery gave focus to two amino acids that reside only in body elastin, desmosine and isodesmosine, which can be measured as biomarkers of elastin degradation in body fluids with increased accuracy and sensitivity. Studies of this biomarker have shown that augmentation therapy in alpha-1 antitrypsin deficiency does decrease lung and body elastic tissue degradation and in the RAPID (Randomized, Placebo-controlled Trial of Augmentation Therapy in Alpha-1 Proteinase Inhibitor Deficiency) Study, over 4 years, showed a preservation of lung density by computer tomography correlating with decreases in plasma levels of desmosine and isodesmosine. This insight indicates the potential of agents that prevent lung elastin degradation. Such an agent is hyaluronan aerosol, which is deficient in post mortem lungs with chronic obstructive pulmonary disease and has been shown to block elastin degradation, possibly by a barrier function. Thus it would appear that hyaluronan could have therapeutic potential in chronic obstructive pulmonary disease.

Topics: alpha 1-Antitrypsin Deficiency; Animals; Biomarkers; Desmosine; Elastin; Humans; Isodesmosine; Leukocyte Elastase; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema

Although chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) seem to be opposite entities from a clinical perspective, common initial pathogenic steps have been suggested in both lung diseases. Emphysema is caused by an elastase/anti-elastase imbalance leading to accelerated elastin degradation. Elastinolysis is however, also accelerated in the IPF patients' lungs. The amino acids desmosine and isodesmosine (DES) are unique to elastin. During the degradation process, elastases liberate DES from elastin fibers. Blood DES levels consequently reflect the rate of systemic elastinolysis and are increased in COPD. This is the first report describing elevated DES levels in IPF patients. We also demonstrated that the age-related increment of DES concentrations is enhanced in IPF. Our current study suggests that elastinolysis is a shared pathogenic step in both COPD and IPF. Further investigation is required to establish the relevance of accelerated elastin degradation in IPF and to determine whether decelerating this process leads to slower progression of lung fibrosis and better survival for patients with IPF.

Topics: Aged; Aging; Biomarkers; Desmosine; Elastin; Female; Humans; Idiopathic Pulmonary Fibrosis; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive

Chronic obstructive pulmonary disease (COPD) is characterized by high levels of protease activity leading to degradation of elastin followed by loss of elasticity of the lung and the development of emphysema. Elastin is an essential structural component of the lung parenchyma to support the expansion and recoil of the alveoli during breathing. The lung extracellular matrix is vulnerable to pathological structural changes upon upregulation of serine proteases, including cathepsin G (CG) and proteinase 3 (PR3). In this study, we explored the diagnostic features of elastin neo-epitopes generated by CG and PR3. Two novel competitive enzyme-linked immunosorbent assays (ELISA) measuring CG and PR3 generated elastin fragments (EL-CG and ELP-3 respectively) were developed for assessment in serum. Both assays were technically robust and biologically validated in serum from patients with COPD. Serological levels of both elastin fragments were significantly elevated in patients with COPD compared to healthy controls. These data suggest that EL-CG and ELP-3 may serve as plausible biologic markers of destructive changes in COPD.

Topics: Aged; Cathepsin G; Elastin; Enzyme-Linked Immunosorbent Assay; Extracellular Matrix; Female; Healthy Volunteers; Humans; Lung; Male; Myeloblastin; Pulmonary Disease, Chronic Obstructive

Accelerated elastin degradation is an important pathogenic mechanism in chronic obstructive pulmonary disease (COPD) leading to irreversible lung function loss and cardiovascular comorbidities. The rate of elastin breakdown is a predictor of mortality in patients with COPD. Decelerating elastinolysis might be an attractive therapeutic target in this debilitating condition. Vascular calcification starts in the elastin network of the arterial wall and is enhanced in patients with COPD. Elastin calcification is accompanied by an upregulation of matrix metalloproteinase gene expression and consequently a shift in the elastase/anti-elastase balance towards degradation. Magnesium can be regarded as a natural calcium antagonist and has the proven ability to ameliorate vascular calcification. Furthermore, an animal study has suggested that magnesium deficiency promotes elastin degradation. I hypothesize that inhibiting elastin calcification by means of magnesium supplementation might counteract both vascular calcification and elastin degradation in COPD. This could potentially have a favorable impact on cardiovascular and respiratory related morbidity/mortality in patients with COPD.

Topics: Animals; Elastin; Humans; Magnesium; Magnesium Deficiency; Models, Biological; Proteolysis; Pulmonary Disease, Chronic Obstructive; Renal Insufficiency, Chronic; Vascular Calcification

Abnormalities in the elastic fiber biology are seen in pulmonary emphysema (PE). The copper-dependent lysyl oxidases regulate the production and accumulation of elastic fibers in the connective tissue. This study focused on the relationship between lysyl oxidase (LOX), LOX-like protein 1 (LOXL1), and LOXL2 and PE pathogenesis. Lung samples with or without PE from patients with chronic obstructive lung disease (n=35) were used. Protein levels of elastin, LOX, LOXL1, LOXL2, hypoxia inducible factor 1-alpha (HIF-1α), copper metabolism domain containing-1 (COMMD1), and phosphatase and tensin homolog (PTEN) were assayed using microscopic and biochemical methods The emphysematous areas were characterized by enlargement of the alveoli, destruction of the alveolar structure, accumulation of macrophages in the alveolar lumens, and showed increased HIF-1α immunoreactivity. Additionally, the emphysematous areas had significantly lower elastin, LOX, LOXL1, LOXL2, HIF-1α, COMMD1, and PTEN protein levels than the non-emphysematous areas. We suppose that the reductions in the HIF-1α levels led to decreases in the protein levels of active LOX, LOXL1, and LOXL2. These decreases might cause abnormalities in the elastic fiber biology. HIF-1α activation induced by decreased COMMD1 and protease activation induced by decreased PTEN might contribute to the development of PE. Finally, methods aimed at increasing the protein levels of LOXs, COMMD1 and PTEN might be effective for treating PE.

Topics: Adaptor Proteins, Signal Transducing; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Cell Nucleus; Copper; Elastin; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Middle Aged; Protein-Lysine 6-Oxidase; PTEN Phosphohydrolase; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema

Extracellular matrix (ECM) remodeling of the lung tissue releases protein fragments into the blood, where they may be detected as serologic surrogate markers of disease activity in COPD. Our goal was to assess the association of ECM turnover with severity and outcome of COPD.. In a prospective, observational, multicenter study including 506 patients with COPD (Global Initiative for Chronic Obstructive Lung Disease grades II to IV), serum samples were analyzed at stable state, exacerbation, and 4 weeks after exacerbation. The analysis comprised a panel of five novel neoepitopes, including fragments of collagen type III (C3M) and collagen type VI (C6M), pro-forms of collagen type III (Pro-C3) and type VI (Pro-C6), and neutrophil elastase-generated fragments of elastin (EL-NE) according to enzyme-linked immunosorbent assay. These neoepitopes were also measured at stable state in a derivation cohort that included 100 patients with COPD.. Serum levels of C3M, C6M, Pro-C3, Pro-C6, and EL-NE were associated with lung function. Patients with the lowest levels of Pro-C3 and Pro-C6 had more severe airflow limitation, hyperinflation, air trapping, and emphysema. C3M and C6M were associated with dyspnea. All ECM biomarkers, except Pro-C6, were increased at exacerbation compared with stable state but, except EL-NE, did not differ between stable state and exacerbation follow-up in the crude and adjusted analyses. In Cox regression adjusted analyses, Pro-C3 was associated with a shorter time to exacerbation (hazard ratio, 0.72; CI, 0.59-0.89; P = .002) and Pro-C6 with survival (hazard ratio, 2.09; CI, 1.18-3.71; P = .011).. Serum biomarkers of ECM turnover were significantly associated with disease severity and clinically relevant outcomes in patients with COPD.. No.: ISRCTN99586989; URL: www.controlled-trials.com.

Topics: Aged; Airway Remodeling; Biomarkers; Collagen; Disease Progression; Elastin; Europe; Extracellular Matrix; Female; Humans; Male; Middle Aged; Outcome Assessment, Health Care; Pulmonary Disease, Chronic Obstructive; Respiratory Function Tests; Severity of Illness Index

Chronic obstructive pulmonary disease (COPD) is characterized by airflow obstruction and loss of lung tissue mainly consisting of extracellular matrix (ECM). Three of the main ECM components are type I collagen, the main constituent in the interstitial matrix, type VI collagen, and elastin, the signature protein of the lungs. During pathological remodeling driven by inflammatory cells and proteases, fragments of these proteins are released into the bloodstream, where they may serve as biomarkers for disease phenotypes. The aim of this study was to investigate the lung ECM remodeling in healthy controls and COPD patients in the COPDGene study.. The COPDGene study recruited 10,300 COPD patients in 21 centers. A subset of 89 patients from one site (National Jewish Health), including 52 COPD patients, 12 never-smoker controls and 25 smokers without COPD controls, were studied for serum ECM biomarkers reflecting inflammation-driven type I and VI collagen breakdown (C1M and C6M, respectively), type VI collagen formation (Pro-C6), as well as elastin breakdown mediated by neutrophil elastase (EL-NE). Correlation of biomarkers with lung function, the SF-36 quality of life questionnaire, and other clinical characteristics was also performed.. The circulating concentrations of biomarkers C6M, Pro-C6, and EL-NE were significantly elevated in COPD patients compared to never-smoking control patients (all p < 0.05). EL-NE was significantly elevated in emphysema patients compared to smoking controls (p < 0.05) and never-smoking controls (p < 0.005), by more than 250%. C1M was inversely associated with forced expiratory volume in 1 s (FEV. These data suggest that type VI collagen turnover and elastin degradation by neutrophil elastase are associated with COPD-induced inflammation (eosinophil-bronchitis) and emphysema. Serological assessment of type VI collagen and elastin turnover may assist in identification of phenotypes likely to be associated with progression and amenable to precision medicine for clinical trials.

Topics: Aged; Biomarkers; Bronchitis; Collagen Type I; Collagen Type VI; Colorado; Comorbidity; Elastin; Extracellular Matrix Proteins; Female; Humans; Lung; Male; Middle Aged; Prevalence; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Pulmonary Eosinophilia; Reproducibility of Results; Risk Factors; Sensitivity and Specificity

A reduced content of alveolar elastic fibers is a key feature of COPD lung. Despite continued elastogenic potential by alveolar fibroblasts in the lung affected by COPD, repair of elastic fibers does not take place, which is due to increased levels of the chondroitin sulfate proteoglycan versican that inhibits the assembly of tropoelastin into fibers. In this study, primary pulmonary fibroblast cell lines from COPD and non-COPD patients were treated with a small interfering RNA (siRNA) against versican to determine if knockdown of versican could restore the deposition of insoluble elastin. Versican siRNA treatment reduced versican expression and secretion by pulmonary fibroblasts from both COPD and non-COPD patients (

Topics: Case-Control Studies; Cell Line; Down-Regulation; Elastin; Fibroblasts; Gene Knockdown Techniques; Humans; Lung; Pulmonary Disease, Chronic Obstructive; RNA Interference; RNA, Small Interfering; RNAi Therapeutics; Solubility; Time Factors; Transfection; Tropoelastin; Versicans

Lung diseases impose a huge economic and health burden worldwide. A key aspect of several adult lung diseases, such as idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD), including emphysema, is aberrant tissue repair, which leads to an accumulation of damage and impaired respiratory function. Currently, there are few effective treatments available for these diseases and their incidence is rising. The planar cell polarity (PCP) pathway is critical for the embryonic development of many organs, including kidney and lung. We have previously shown that perturbation of the PCP pathway impairs tissue morphogenesis, which disrupts the number and shape of epithelial tubes formed within these organs during embryogenesis. However, very little is known about the role of the PCP pathway beyond birth, partly because of the perinatal lethality of many PCP mouse mutant lines. Here, we investigate heterozygous

Topics: A549 Cells; Actin Cytoskeleton; Aging; Animals; Cell Movement; Cell Polarity; Down-Regulation; Elastin; Embryo, Mammalian; Gene Knockdown Techniques; Heterozygote; Homeostasis; Humans; Lung; Macrophages; Membrane Proteins; Mice; Models, Biological; Mutation; Nerve Tissue Proteins; Phenotype; Polymorphism, Genetic; Pulmonary Disease, Chronic Obstructive; Smoking; Tumor Suppressor Proteins; Wound Healing

Elastin degradation is a key feature of emphysema and may have a role in the pathogenesis of atherosclerosis associated with chronic obstructive pulmonary disease (COPD). Circulating desmosine is a specific biomarker of elastin degradation. We investigated the association between plasma desmosine (pDES) and emphysema severity/progression, coronary artery calcium score (CACS) and mortality.pDES was measured in 1177 COPD patients and 110 healthy control subjects from two independent cohorts. Emphysema was assessed on chest computed tomography scans. Aortic arterial stiffness was measured as the aortic-femoral pulse wave velocity.pDES was elevated in patients with cardiovascular disease (p<0.005) and correlated with age (rho=0.39, p<0.0005), CACS (rho=0.19, p<0.0005) modified Medical Research Council dyspnoea score (rho=0.15, p<0.0005), 6-min walking distance (rho=-0.17, p<0.0005) and body mass index, airflow obstruction, dyspnoea, exercise capacity index (rho=0.10, p<0.01), but not with emphysema, emphysema progression or forced expiratory volume in 1 s decline. pDES predicted all-cause mortality independently of several confounding factors (p<0.005). In an independent cohort of 186 patients with COPD and 110 control subjects, pDES levels were higher in COPD patients with cardiovascular disease and correlated with arterial stiffness (p<0.05).In COPD, excess elastin degradation relates to cardiovascular comorbidities, atherosclerosis, arterial stiffness, systemic inflammation and mortality, but not to emphysema or emphysema progression. pDES is a good biomarker of cardiovascular risk and mortality in COPD.

Topics: Adult; Aged; Biomarkers; Body Composition; Bronchodilator Agents; Calcinosis; Cardiovascular Diseases; Case-Control Studies; Coronary Vessels; Desmosine; Disease Progression; Elastin; Emphysema; Female; Forced Expiratory Volume; Humans; Inflammation; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Pulse Wave Analysis; Respiratory Function Tests; Risk Factors; Smoking; Vascular Stiffness

Topics: Adult; Age Factors; Aged; Aged, 80 and over; Desmosine; Elastin; Female; Forced Expiratory Volume; Humans; Isodesmosine; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; Smoking; Time Factors

The excessive activities of the serine proteinases neutrophil elastase and proteinase 3 are associated with tissue damage in chronic obstructive pulmonary disease. Reduced concentrations and/or inhibitory efficiency of the main circulating serine proteinase inhibitor α-1-antitrypsin result from point mutations in its gene. In addition, α-2-macroglobulin competes with α-1-antitrypsin for proteinases, and the α-2-macroglobulin-sequestered enzyme can retain its catalytic activity. We have studied how serine proteinases partition between these inhibitors and the effects of α-1-antitrypsin mutations on this partitioning. Subsequently, we have developed a three-dimensional reaction-diffusion model to describe events occurring in the lung interstitium when serine proteinases diffuse from the neutrophil azurophil granule following degranulation and subsequently bind to either α-1-antitrypsin or α-2-macroglobulin. We found that the proteinases remained uninhibited on the order of 0.1 s after release and diffused on the order of 10 μm into the tissue before becoming sequestered. We have shown that proteinases sequestered to α-2-macroglobulin retain their proteolytic activity and that neutrophil elastase complexes with α-2-macroglobulin are able to degrade elastin. Although neutrophil elastase is implicated in the pathophysiology of emphysema, our results highlight a potentially important role for proteinase 3 because of its greater concentration in azurophil granules, its reduced association rate constant with all α-1-antitrypsin variants studied here, its greater diffusion distance, time spent uninhibited following degranulation, and its greater propensity to partition to α-2-macroglobulin where it retains proteolytic activity.

Topics: alpha 1-Antitrypsin; alpha-Macroglobulins; Elastin; Humans; Leukocyte Elastase; Lung; Myeloblastin; Neutrophils; Pulmonary Disease, Chronic Obstructive

Isodesmosine and desmosine are crosslinking amino acids that are present only in elastin. They are useful biomarkers for the degradation of elastin, which occurs during the progression of chronic obstructive pulmonary disease (COPD) and related diseases. This Letter describes the synthesis of [(13)C3,(15)N1]-labeled isodesmosine, using Chichibabin pyridine synthesis as a key reaction. The labeled isodesmosine is a potential internal standard for the quantitative LC-MS/MS analysis of desmosines in elastin degradation.

Topics: Biomarkers; Carbon Isotopes; Chromatography, Liquid; Desmosine; Elastin; Isodesmosine; Molecular Structure; Nitrogen Isotopes; Pulmonary Disease, Chronic Obstructive; Tandem Mass Spectrometry

The tetrasubstituted pyridinium amino acids isodesmosine and desmosine are cross-linkers of elastin and are attractive biomarkers for the diagnosis of chronic obstructive pulmonary disease (COPD). In this study, the biomimetic total synthesis of isodesmosine and desmosine via a lanthanide-promoted Chichibabin pyridine synthesis using the corresponding aldehyde and amine hydrochloride is reported.

Topics: Biomarkers; Biomimetics; Cross-Linking Reagents; Desmosine; Elastin; Humans; Isodesmosine; Lanthanoid Series Elements; Molecular Structure; Pulmonary Disease, Chronic Obstructive; Pyridines; Pyridinium Compounds

Remodelling in COPD has at least two dimensions: small airway wall thickening and destruction of alveolar walls. Recent studies indicate that there is some similarity between alveolar and small airway wall matrix remodelling. The aim of this study was to characterise and assess similarities in alveolar and small airway wall matrix remodelling, and TGF-β signalling in COPD patients of different GOLD stages.. Lung tissue sections of 14 smoking controls, 16 GOLD II and 19 GOLD IV patients were included and stained for elastin and collagens as well as hyaluronan, a glycosaminoglycan matrix component and pSMAD2.. Elastin was significantly decreased in COPD patients not only in alveolar, but also in small airway walls. Interestingly, both collagen and hyaluronan were increased in alveolar as well as small airway walls. The matrix changes were highly comparable between GOLD stages, with collagen content in the alveolar wall increasing further in GOLD IV. A calculated remodelling index, defined as elastin divided over collagen and hyaluronan, was decreased significantly in GOLD II and further lowered in GOLD IV patients, suggesting that matrix component alterations are involved in progressive airflow limitation. Interestingly, there was a positive correlation present between the alveolar and small airway wall stainings of the matrix components, as well as for pSMAD2. No differences in pSMAD2 staining between controls and COPD patients were found.. In conclusion, remodelling in the alveolar and small airway wall in COPD is markedly similar and already present in moderate COPD. Notably, alveolar collagen and a remodelling index relate to lung function.

Topics: Airway Remodeling; Biopsy, Needle; Bronchi; Case-Control Studies; Chi-Square Distribution; Elastin; Extracellular Matrix; Female; Fibrillar Collagens; Humans; Immunohistochemistry; Male; Middle Aged; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive; Reference Values; Severity of Illness Index; Smad2 Protein

Remodeling in chronic obstructive pulmonary disease (COPD) has at least two dimensions: small airway wall thickening and destruction of alveolar walls. Recently we showed comparable alterations of the extracellular matrix (ECM) compounds collagen, hyaluoran, and elastin in alveolar and small airway walls of COPD patients. The aim of this study was to characterize and assess similarities in alveolar and small airway wall matrix remodeling in chronic COPD models. From this comparative characterization of matrix remodeling we derived and elaborated underlying mechanisms to the matrix changes reported in COPD. Lung tissue sections of chronic models for COPD, either induced by exposure to cigarette smoke, chronic intratracheal lipopolysaccharide instillation, or local tumor necrosis factor (TNF) expression [surfactant protein C (SPC)-TNFα mice], were stained for elastin, collagen, and hyaluronan. Furthermore TNF-α matrix metalloproteinase (MMP)-2, -9, and -12 mRNA expression was analyzed using qPCR and localized using immunohistochemistry. Both collagen and hyaluronan were increased in alveolar and small airway walls of all three models. Interestingly, elastin contents were differentially affected, with a decrease in both alveolar and airway walls in SPC-TNFα mice. Furthermore TNF-α and MMP-2 and -9 mRNA and protein levels were found to be increased in alveolar walls and around airway walls only in SPC-TNFα mice. We show that only SPC-TNFα mice show changes in elastin remodeling that are comparable to what has been observed in COPD patients. This reveals that the SPC-TNFα model is a suitable model to study processes underlying matrix remodeling and in particular elastin breakdown as seen in COPD. Furthermore we indicate a possible role for MMP-2 and MMP-9 in the breakdown of elastin in airways and alveoli of SPC-TNFα mice.

Topics: Airway Remodeling; Animals; Disease Models, Animal; Elastin; Extracellular Matrix; Fibrillar Collagens; Gene Expression; Hyaluronic Acid; Lipopolysaccharides; Male; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Mice; Mice, Inbred C57BL; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive; Smoking; Tumor Necrosis Factor-alpha

Chemical synthesis of the deuterium isotope desmosine-d4 has been achieved. This isotopic compound possesses all four deuterium atoms at the alkanyl carbons of the alkyl amino acid substitution in the desmosine molecule and is stable toward acid hydrolysis; this is required in the measurement of two crosslinking molecules, desmosine and isodesmosine, as biomarkers of elastic tissue degradation. The degradation of elastin occurs in several widely prevalent diseases. The synthesized desmosine-d₄ is used as the internal standard to develop an accurate and sensitive isotope-dilution liquid chromatography-tandem mass spectrometry analysis, which can serve as a generalized method for an accurate analysis of desmosine and isodesmosine as biomarkers in many types of biological tissues involving elastin degradation.

Topics: Biomarkers; Bronchoalveolar Lavage; Chromatography, Liquid; Desmosine; Deuterium; Elastin; Humans; Isodesmosine; Proteolysis; Pulmonary Disease, Chronic Obstructive; Reference Standards; Tandem Mass Spectrometry

Elastin is a signature protein of the arteries and lungs, thus it was hypothesized that elastin is subject to enzymatic degradation during cardiovascular and pulmonary diseases. The aim was to investigate if different fragments of the same protein entail different information associated to two different diseases and if these fragments have the potential of being diagnostic biomarkers.. Monoclonal antibodies were raised against an identified fragment (the ELM-2 neoepitope) generated at the amino acid position '552 in elastin by matrix metalloproteinase (MMP) -9/-12. A newly identified ELM neoepitope was generated by the same proteases but at amino acid position '441. The distribution of ELM-2 and ELM, in human arterial plaques and fibrotic lung tissues were investigated by immunohistochemistry. A competitive ELISA for ELM-2 was developed. The clinical relevance of the ELM and ELM-2 ELISAs was evaluated in patients with acute myocardial infarction (AMI), no AMI, high coronary calcium, or low coronary calcium. The serological release of ELM-2 in patients with chronic obstructive pulmonary disease (COPD) or idiopathic pulmonary fibrosis (IPF) was compared to controls.. ELM and ELM-2 neoepitopes were both localized in diseased carotid arteries and fibrotic lungs. In the cardiovascular cohort, ELM-2 levels were 66% higher in serum from AMI patients compared to patients with no AMI (p<0.01). Levels of ELM were not significantly increased in these patients and no correlation was observed between ELM-2 and ELM. ELM-2 was not elevated in the COPD and IPF patients and was not correlated to ELM. ELM was shown to be correlated with smoking habits (p<0.01).. The ELM-2 neoepitope was related to AMI whereas the ELM neoepitope was related to pulmonary diseases. These results indicate that elastin neoepitopes generated by the same proteases but at different amino acid sites provide different tissue-related information depending on the disease in question.

Topics: Antibodies, Monoclonal, Murine-Derived; Elastin; Enzyme-Linked Immunosorbent Assay; Epitopes; Female; Humans; Idiopathic Pulmonary Fibrosis; Male; Myocardial Infarction; Plaque, Atherosclerotic; Proteolysis; Pulmonary Disease, Chronic Obstructive

Neutrophils play an important role in the inflammatory process associated with chronic obstructive pulmonary disease (COPD). Lung-infiltrating neutrophils secrete elastinolytic proteases that participate in elastin breakdown and the formation of elastin peptides (EPs).. We hypothesized that circulating neutrophil-associated immune response may be modulated by EPs during COPD.. Neutrophils obtained from patients with either stable or exacerbated COPD and controls were cultured with or without EPs. Cell chemotaxis was analysed by the Boyden method and cytokine expression was analysed by ELISA and real-time reverse transcriptase PCR. Bacterial phagocytosis and killing of ingested bacteria were evaluated after incubation with Pseudomonas aeruginosa. Reactive oxygen species (ROS) measurement and elastin receptor expression were determined by flow cytometry.. Chemotactic activity of neutrophils from patients with COPD towards the VGVAPG EP was reduced compared with controls. VGVAPG increased proinflammatory cytokine synthesis and bacterial load, but reduced ROS production in neutrophils from controls and from patients with stable COPD. Patients with exacerbated COPD were unresponsive to VGVAPG treatment. These findings were associated with a decreased or almost complete loss of S-Gal elastin receptor expression in neutrophils from patients with stable or exacerbated COPD, respectively.. The study demonstrates that the response of neutrophils from patients with COPD to VGVAPG varied according to COPD phase and critical level of S-Gal expression. S-Gal downregulation could result from a feedback mechanism induced by high levels of EPs.

Topics: Aged; Cells, Cultured; Chemotaxis; Cytokines; Elastin; Female; Flow Cytometry; Humans; Leukocyte Count; Male; Middle Aged; Neutrophil Activation; Neutrophils; Pulmonary Disease, Chronic Obstructive; Reactive Oxygen Species; Receptors, Cell Surface; Smoking; Sputum

Desmosine, a crosslinking amino acid of elastin, is an attractive biomarker for diagnosis of chronic obstructive pulmonary disease (COPD). In this study, the first total synthesis of (+)-desmosine was achieved in 11% overall yield in 13 steps utilizing stepwise and regioselective Sonogashira cross-coupling reactions.

Topics: Biomarkers; Cross-Linking Reagents; Desmosine; Elastin; Molecular Structure; Pulmonary Disease, Chronic Obstructive; Stereoisomerism

Development of emphysema and vascular stiffness in chronic obstructive pulmonary disease (COPD) may be due to a common mechanism of susceptibility to pulmonary and systemic elastin degradation.. To investigate whether patients with COPD have evidence of systemic elastin degradation in the skin.. The authors measured cutaneous elastin degradation using immunohistochemistry (percentage area of elastin fibres) in sun-exposed (exposed) and non-sun-exposed (non-exposed) skin biopsies in 16 men with COPD and 15 controls matched for age and cigarette smoke exposure. Quantitative PCR of matrix metalloproteinase (MMP)-2, -9, -12 and tissue inhibitor of metalloproteinase-1 mRNA and zymography for protein expression of MMP-2 and -9 were performed on homogenised skin. Arterial stiffness and emphysema severity were measured using carotid-femoral pulse wave velocity and quantitative CT scanning.. Skin elastin degradation was greater in exposed and non-exposed skin of patients with COPD compared with controls (exposed, mean (SD); 43.5 (12.1)% vs 26.3 (6.9)%, p<0.001; non-exposed 22.4 (5.2)% vs 18.1 (4.3)%, p=0.02). Cutaneous expression of MMP-9 mRNA and proMMP-9 concentrations was increased in exposed skin of COPD patients (p=0.004 and p=0.02, respectively) and was also associated with increased skin elastin degradation (r=0.62, p<0.001 and r=0.47, p=0.01, respectively). In the entire cohort of ex-smokers, cutaneous elastin degradation was associated with emphysema severity, FEV(1) and pulse wave velocity.. Patients with COPD have increased skin elastin degradation compared with controls, which is related to emphysema severity and arterial stiffness. Systemic elastin degradation due to increased proteolytic activity may represent a novel shared mechanism for the pulmonary, vascular and cutaneous features of COPD.

Topics: Aged; Biopsy; Disease Progression; Elastin; Enzyme Precursors; Forced Expiratory Volume; Gene Expression Regulation; Humans; Immunohistochemistry; Male; Matrix Metalloproteinase 9; Middle Aged; Polymerase Chain Reaction; Pulmonary Disease, Chronic Obstructive; Respiratory Function Tests; RNA, Messenger; Skin; Smoking

Antielastin autoimmunity has been hypothesised to drive disease progression in chronic obstructive pulmonary disease (COPD). The proposed mechanism is currently disputed by conflicting data. The authors aimed to explore antibody responses against elastin in a large and extensively characterised COPD population and to assess elastin-specific peripheral T-cell reactivity in a representative subgroup.. Antielastin antibodies were analysed with indirect ELISA on the plasma of 320 patients with COPD (Global Initiative for Chronic Obstructive Lung Disease 1-4) and 143 smoking controls. In a second group of 40 patients with COPD and smoking controls, T-cell responses against extracellular matrix (elastin, collagen I and collagen V) were determined with enzyme-linked immunosorbent spot (EliSpot) (interferon γ (IFNγ) and interleukin-2) on peripheral blood mononuclear cells and compared with the responses of 11 never-smoking controls.. Antielastin antibody titres were not elevated in patients with COPD compared with smoking controls and even decreased significantly with increasing severity of COPD (p<0.001). Lower antielastin antibody titres were also found in a subgroup of patients with CT-proven emphysema. Elastin-specific INFγ-mediated T helper 1 responses could not be revealed in smoking subjects with and without COPD. Collagen I-mediated T-cell responses were also absent, which contrasted with a significant increased anticollagen V response in the smoking controls and patients with COPD compared with the never smokers (p=0.008). Collagen V-mediated T-cell responses could not discriminate between patients with COPD and smoking controls.. A systemic immune response against elastin could not be identified in patients with COPD. By contrast, collagen V-mediated autoimmunity was increased in the subgroup of smokers and may potentially contribute to the pathogenesis of COPD.

Topics: Aged; Autoantibodies; Autoimmunity; B-Lymphocytes; Collagen Type V; Elastin; Extracellular Matrix; Female; Forced Expiratory Volume; Humans; Immunity, Cellular; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; Smoking; T-Lymphocytes; Vital Capacity

Elastin is an essential component of selected connective tissues that provides a unique physiological elasticity. Elastin may be considered a signature protein of lungs where matrix metalloprotease (MMP) -9-and -12, may be considered the signature proteases of the macrophages, which in part are responsible for tissue damage during disease progression. Thus, we hypothesized that a MMP-9/-12 generated fragment of elastin may be a relevant biochemical maker for lung diseases.. Elastin fragments were identified by mass-spectrometry and one sequence, generated by MMP-9 and -12 (ELN-441), was selected for monoclonal antibody generation and used in the development of an ELISA. Soluble and insoluble elastin from lung was cleaved in vitro and the time-dependent release of fragments was assessed in the ELN-441 assay. The release of ELN-441 in human serum from patients with chronic obstructive pulmonary disease (COPD) (n = 10) and idiopathic pulmonary fibrosis (IPF) (n = 29) were compared to healthy matched controls (n = 11).. The sequence ELN-441 was exclusively generated by MMP-9 and -12 and was time-dependently released from soluble lung elastin. ELN-441 levels were 287% higher in patients diagnosed with COPD (p < 0.001) and 124% higher in IPF patients (p < 0.0001) compared with controls. ELN-441 had better diagnostic value in COPD patients (AUC 97%, p = 0.001) than in IPF patients (AUC 90%, p = 0.0001). The odds ratios for differentiating controls from COPD or IPF were 24 [2.06-280] for COPD and 50 [2.64-934] for IPF.. MMP-9 and -12 time-dependently released the ELN-441 epitope from elastin. This fragment was elevated in serum from patients with the lung diseases IPF and COPD, however these data needs to be validated in larger clinical settings.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; Biomarkers; Case-Control Studies; Elastin; Enzyme-Linked Immunosorbent Assay; Epitopes; Humans; Idiopathic Pulmonary Fibrosis; In Vitro Techniques; Matrix Metalloproteinase 12; Matrix Metalloproteinase 9; Mice; Mice, Inbred BALB C; Molecular Sequence Data; Pulmonary Disease, Chronic Obstructive; Sensitivity and Specificity; Time Factors

Liberation of elastin peptides from damaged lung may be a mechanism of autoimmune lung disease. Citrullination, and anti-citrullinated protein antibody formation occurs in smokers, but the role of smoking in autoantibody generation relevant to pulmonary disease is unclear. Anti-elastin, anti-cyclic citrullinated peptide (anti-CCP) and anti-mutated citrullinated vimentin (anti-MCV) antibodies were measured in 257 subjects with α₁-antitrypsin deficiency (AATD), 113 subjects with usual chronic obstructive pulmonary disease (COPD) and 22 healthy nonsmokers. Levels were compared between groups, against phenotypic features and against smoke exposure. Anti-elastin antibodies were higher in controls relative to AATD (p = 0.008) and usual COPD (p < 0.00001), and in AATD relative to usual COPD (p < 0.00001). Anti-elastin levels showed a threshold at 10 pack-yrs, being higher in those who had smoked less (p = 0.004). No relationships between antibody levels and clinical phenotype were seen after adjustment for smoke exposure. Anti-CCP antibodies were higher in usual COPD than AATD (p = 0.002) but the relationship to smoke exposure was less clear. Smoke exposure is the main determinant of anti-elastin antibody levels, which fall after 10 pack-yrs. Local antibody complexes may be a better measure of elastin directed autoimmunity than circulating levels.

Topics: Adult; Aged; alpha 1-Antitrypsin Deficiency; Autoimmune Diseases; Elastin; Female; Forced Expiratory Volume; Humans; Lung Diseases; Male; Middle Aged; Phenotype; Pulmonary Disease, Chronic Obstructive; Risk; Smoking; Time Factors

Tobacco smoke is a major risk factor in the development of COPD. Secondhand smoke (SHS) exposure is a known risk factor in asthma, bronchitis, and coronary artery disease. Elastin is a recognized target for injury in COPD, and the amino acids desmosine and isodesmosine (D/I), which are specific for elastin degradation, are elevated in COPD. This study determined whether exposure to SHS affects elastin degradation in asymptomatic individuals.. Two cohorts of asymptomatic individuals without evidence of respiratory or circulatory disease, exposed to SHS, were studied. Both cohorts comprised normal nonsmokers, active smokers, and those exposed to SHS. D/I were measured in plasma and quantified by high-performance liquid chromatography and tandem mass spectrometry by published methods. Plasma cotinine, a metabolite of nicotine, was also measured.. In each cohort, the levels of D/I in plasma were statistically significantly higher in secondhand-smoke-exposed subjects than in the normal nonexposed subjects. Smokers had the highest levels of D/I but their levels were not statistically significantly higher than those of the secondhand-smoke-exposed. Cotinine levels were elevated in secondhand-smoke-exposed subjects and active smokers but not in most nonsmoking control subjects.. Results indicate a tissue matrix effect of degradation of body elastin from SHS exposure and possible lung structure injury, which may result in COPD. Long-term studies of individuals exposed to SHS for the development of COPD are warranted.

Topics: Adult; Aged; Biomarkers; Cohort Studies; Cotinine; Desmosine; Elastin; Female; Humans; Isodesmosine; Male; Middle Aged; Nicotine; Pulmonary Disease, Chronic Obstructive; Risk Factors; Smoking; Tobacco Smoke Pollution; Young Adult

Topics: Aged; Aged, 80 and over; Autoantibodies; Collagen; Decorin; Elastin; Humans; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; Severity of Illness Index; Smoking

Insufficiency of tissue repair by pulmonary fibroblasts may contribute to the decrease in elastic fibres in chronic obstructive pulmonary disease (COPD). In this study, the repair function of COPD fibroblasts was assessed by examining the response to transforming growth factor (TGF)-β1. Primary pulmonary fibroblasts were cultured from lung tissue of COPD patients and smoking control subjects. Cellular proliferation was measured with Alamar Blue reduction method. Levels of tropoelastin mRNA and soluble elastin was measured using real-time RT-PCR and Fastin elastin assay respectively. The percentage of increase in proliferation and elastin production after TGF-β1 (1 ng/ml) treatment was calculated for fibroblasts from each subject. COPD fibroblasts showed slower proliferation than control fibroblasts, and a reduced response to TGF-β1 stimulation. The promotive effect of TGF-β1 on elastin synthesis in control fibroblasts was significantly diminished in fibroblasts from COPD patients. Our findings indicate that COPD lung fibroblasts have a significantly decreased response to TGF-β1 in terms of proliferation and elastin production.

Topics: Aged; Cell Proliferation; Cells, Cultured; Elastin; Female; Fibroblasts; Gene Expression Regulation; Humans; Lung; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive; RNA, Messenger; Transforming Growth Factor beta1; Tropoelastin

Chronic obstructive pulmonary disease and emphysema develops in 15% of ex-smokers despite sustained quitting, while 10% are free of emphysema or severe lung obstruction. The cause of the incapacity of the immune system to clear the inflammation in the first group remains unclear.. We searched genes that were protecting ex-smokers without emphysema, using microarrays on portions of human lungs surgically removed; we found that loss of lung function in patients with chronic obstructive pulmonary disease and emphysema was associated with a lower expression of CD46 and verified this finding by qRT-PCR and flow cytometry. Also, there was a significant association among decreased CD46(+) cells with decreased CD4(+)T cells, apoptosis mediator CD95 and increased CD8(+)T cells that were protecting patients without emphysema or severe chronic obstructive pulmonary disease. CD46 not only regulates the production of T regulatory cells, which suppresses CD8(+)T cell proliferation, but also the complement cascade by degradation of C3b. These results were replicated in the murine smoking model, which showed increased C5a (produced by C3b) that suppressed IL12 mediated bias to T helper 1 cells and elastin co-precipitation with C3b, suggesting that elastin could be presented as an antigen. Thus, using ELISA from elastin peptides, we verified that 43% of the patients with severe early onset of chronic obstructive pulmonary disease tested positive for IgG to elastin in their serum compared to healthy controls.. These data suggest that higher expression of CD46 in the lungs of ex-smoker protects them from emphysema and chronic obstructive pulmonary disease by clearing the inflammation impeding the proliferation of CD8(+) T cells and necrosis, achieved by production of T regulatory cells and degradation of C3b; restraining the complement cascade favors apoptosis over necrosis, protecting them from autoimmunity and chronic inflammation.

Topics: Aged; Animals; Complement C3b; Elastin; Enzyme-Linked Immunosorbent Assay; fas Receptor; Female; Humans; Immunohistochemistry; Lung; Male; Membrane Cofactor Protein; Mice; Middle Aged; Oligonucleotide Array Sequence Analysis; Pulmonary Disease, Chronic Obstructive; Signal Transduction; Smoking; T-Lymphocytes, Regulatory

The aim of this study is to develop a standardized LC-MS/MS method for accurate measurement of desmosine (DES) and isodesmosine (IDS) in all body fluids as biomarkers for in vivo degradation of matrix tissue elastin in man and animals. A reproducible three-step analytical procedure: (1) sample hydrolysis in 6N HCl, (2) SPE by a CF1 cartridge with addition of acetylated pyridinoline as internal standard (IS), and (3) LC/MSMS analysis by SRM monitoring of transition ions; DES or IDS (m/z 526-481+397) and IS (m/z 471-128) was developed. The method achieves accurate measurements of DES/IDS in accessible body fluids (i.e. urine, plasma, and sputum). LOQ of DES/IDS in body fluids is 0.1 ng/ml. The % recoveries and reproducibility from urine, plasma, and sputum samples are above 99 ± 8% (n = 3), 94 ± 9% (n = 3) and 87 ± 11% (n = 3), with imprecision 8%, 9% and 10%, respectively. The proposed method was applied to measure DES/IDS in body fluids of patients with chronic obstructive pulmonary disease (COPD) and healthy controls. Total DES/IDS in sputum and plasma is increased over normal controls along with the free DES/IDS in urine in patients. DES/IDS can be used to study the course of COPD and the response to therapy. This practical and reliable LC-MS/MS method is proposed as a standardized method to measure DES and IDS in body fluids. This method can have wide application for investigating diseases which involve elastic tissue degradation.

Topics: Amino Acids; Biomarkers; Case-Control Studies; Chromatography, Liquid; Desmosine; Elastin; Humans; Hydrochloric Acid; Hydrolysis; Isodesmosine; Pulmonary Disease, Chronic Obstructive; Reproducibility of Results; Sensitivity and Specificity; Sputum; Tandem Mass Spectrometry

In patients with chronic inflammatory lung disease, pulmonary proteases can generate neoantigens from elastin and collagen with the potential to fuel autoreactive immune responses. Antielastin peptide antibodies have been implicated in the pathogenesis of tobacco-smoke-induced emphysema. Collagen-derived peptides may also play a role.. To determine whether autoantibodies directed against elastin- and collagen-derived peptides are present in plasma from three groups of patients with chronic inflammatory lung disease compared with a nonsmoking healthy control group and to identify whether autoimmune responses to these peptides may be an important component of the disease process in these patients.. A total of 124 patients or healthy control subjects were recruited for the study (Z-A1AT deficiency, n = 20; cystic fibrosis, n = 40; chronic obstructive pulmonary disease, n = 31; healthy control, n = 33). C-reactive protein, IL-32, and antinuclear antibodies were quantified. Antielastin and anti-N-acetylated-proline-glycine-proline autoantibodies were measured by reverse ELISA.. All patients were deemed stable and noninfective on the basis of the absence of clinical or radiographic evidence of recent infection. There were no significant differences in the levels of autoantibodies or IL-32 in the patients groups compared with the healthy control subjects.. Antielastin or anti-N-acetylated proline-glycine-proline autoantibodies are not evident in chronic inflammatory lung disease.

Topics: Adolescent; Adult; Aged; alpha 1-Antitrypsin Deficiency; Autoantibodies; Autoimmune Diseases; Case-Control Studies; Cystic Fibrosis; Elastin; Female; Humans; Male; Middle Aged; Oligopeptides; Pulmonary Disease, Chronic Obstructive; Smoking; Young Adult

Williams-Beuren syndrome (WBS) is caused by a submicroscopic deletion on chromosome 7q11.23 that encompasses the entire elastin (ELN) gene. Elastin, a key component of elastic fibers within the lung, is progressively destroyed in emphysema. Defects in the elastin gene have been associated with increased susceptibility towards developing chronic obstructive pulmonary disease (COPD) and emphysema in both humans and mice. We postulate that hemizygosity at the elastin gene locus may increase susceptibility towards the development of COPD and emphysema in subjects with WBS. We describe an adult subject with WBS who was a lifelong non-smoker and was found to have moderate emphysema. We also examined the pulmonary function of a separate cohort of adolescents and young adults with WBS. Although no significant spirometric abnormalities were identified, a significant proportion of subjects reported respiratory symptoms. Thus, while significant obstructive disease does not appear to be common in relatively young adults with WBS, subclinical emphysema and lung disease may exist which possibly could worsen with advancing age. Further investigation may elucidate the pathogenesis of non-smoking-related emphysema.

Topics: Adolescent; Adult; Animals; Case-Control Studies; Chromosome Deletion; Chromosomes, Human, Pair 7; Elastin; Female; Humans; Male; Mice; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Respiratory Function Tests; Williams Syndrome; Young Adult

This study presents a method for detecting and characterizing peptides of elastin that result from lung matrix injury in chronic obstructive pulmonary disease (COPD). Lung elastin degradation was studied by two representative in vivo elastases, human neutrophil elastase (HNE) and macrophage metalloproteinase (MMP12). The resulting peptide mixtures were analyzed by high-performance liquid chromatography/electrospray tandem mass spectrometry (LC/MSMS) to characterize 40 elastin-derived peptides (EDPs), 24 from HNE and 16 from MMP12 digestions. The peptides constitute major EDPs that are solubilized by the enzymatic digestion. Using the selected reaction monitoring (SRM) from LC/MSMS analysis, the transition ions of the peptides were used to investigate the presence of the peptides in selected body fluids of chronic obstructive pulmonary disease (COPD) patients. Four peptides, GYPI, APGVGV, GLGAFPA, and VGVLPGVPT, were detected in plasma or sputum of some COPD patients but not in normal controls. A hexapeptide VGVAPG, which had been widely studied for its chemotactic activity for a possible pathogenic role in COPD, was not detected in lung EDPs by HNE or MMP12 digestion, but only by porcine pancreatic elastase (PPE) digestion. This study demonstrates a practical methodology to study peptides from matrix degradations in pulmonary disease and a means of investigating their pathogenesis.

Topics: Adult; Aged; Aged, 80 and over; Biomarkers; Chromatography, High Pressure Liquid; Elastin; Female; Humans; Leukocyte Elastase; Lung; Male; Matrix Metalloproteinase 12; Middle Aged; Peptide Fragments; Peptide Mapping; Pulmonary Disease, Chronic Obstructive; Spectrometry, Mass, Electrospray Ionization; Sputum; Tandem Mass Spectrometry

The destruction of elastic fibers has been implicated in the pathogenesis of chronic obstructive pulmonary disease (COPD). Emphysema has been described in autosomal dominant cutis laxa, which can be caused by mutations in the elastin gene. Previously, a rare functional mutation in the terminal exon of elastin was found in a case of severe, early-onset COPD. To test the hypothesis that other similar elastin mutations may predispose to COPD, we screened 90 probands from the Boston Early-Onset COPD Study and 90 smoking control subjects from the Normative Aging Study for mutations in elastin exons using high-resolution DNA melt analysis followed by resequencing. Rare nonsynonymous single-nucleotide polymorphisms (SNPs) seen only in cases were examined for segregation with airflow obstruction within pedigrees. Common nonsynonymous SNPs were tested for association with COPD in a family-based analysis of 949 subjects from the Boston Early-Onset COPD Study, and in a case-control analysis in 389 COPD cases from the National Emphysema Treatment Trial and 472 control subjects from the Normative Aging Study. Of 28 elastin variants found, 3 were nonsynonymous SNPs found only in cases. The previously described Gly773Asp mutation was found in another proband. The other two SNPs did not clearly segregate with COPD within families. Two common nonsynonymous SNPs did not demonstrate significant associations in either a family-based or case-control analysis. Exonic SNPs in the elastin gene do not appear to be common risk factors for severe COPD.

Topics: Adult; Aged; Case-Control Studies; Elastin; Emphysema; Exons; Female; Genetic Variation; Humans; Male; Middle Aged; Pedigree; Polymorphism, Genetic; Polymorphism, Single Nucleotide; Pulmonary Disease, Chronic Obstructive

Desmosine and Isodesmosine (D/I) are cross-linking amino acids which are present only in mature elastin. Changes in their concentration in body fluids indicate changes in elastin degradation and can be a reflection of tissue elastase activity. This study was undertaken to determine whether continuous therapy with the long-acting bronchodilator Tiotropium bromide (TTP) could result in reductions in D/I as measured by mass spectrometry in plasma, urine and sputum.. Twelve not currently smoking patients with chronic obstructive pulmonary disease (COPD), never on TTP, were selected for study. Levels of D/I, along with measurements of FVC, FEV1 and FEV1/FVC. were determined before starting TTP daily, and then one and two months after.. D/I decreased in plasma (10 of 12 patients), in sputum all (12 of 12), and in the percentage of free D/I in urine (10 of 12). Most patients showed slight increases in FVC and FEV1 percent predicted over two months.. The results are consistent with an effect of prolonged bronchodilitation by anti-cholinergic blockade to also result in reduced lung elastin degradation.

Topics: Bronchodilator Agents; Desmosine; Elastin; Forced Expiratory Volume; Humans; Isodesmosine; Pancreatic Elastase; Pulmonary Disease, Chronic Obstructive; Scopolamine Derivatives; Smoking Cessation; Tiotropium Bromide; Vital Capacity

Alveolar elastic fibres are key targets of proteases during the pathogenesis of chronic obstructive pulmonary disease (COPD). In the current study, we hypothesised that a response to injury leads to enhanced alveolar elastin gene expression in very severe COPD. Lung samples obtained from 43 patients, including 11 with very severe COPD (stage 4), 10 donors, 10 with moderate/severe COPD (stage 2-3) and 12 non-COPD subjects, were analysed for elastin mRNA expression by real-time RT-PCR and in situ hybridisation. Alveolar elastic fibres were visualised using Hart's staining of sections of frozen inflated lungs obtained from 11 COPD stage 4 patients and three donor lungs. Compared with donors, non-COPD and stage 2-3 COPD, elastin mRNA expression was significantly increased in very severe COPD lungs (12-fold change), and localised in situ hybridisation induced elastin expression to alveolar walls. Compared with donors, alveolar elastic fibres also comprised a greater volume fraction of total lung tissue in very severe COPD lungs (p<0.01), but elastic fibre content was not increased per lung volume, and desmosine content was not increased. The present study demonstrates enhanced alveolar elastin expression in very severe COPD. The efficiency of this potential repair mechanism and its regulation remain to be demonstrated.

Topics: Adult; Aged; Elastin; Female; Gene Expression Regulation; Humans; In Situ Hybridization; Lung Transplantation; Male; Middle Aged; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Smoking

Desmosine (DES) and isodesmosine (IDES) are two unusual, tetrafunctional, pyridinium ring-containing amino acids involved in elastin cross-linking. Being amino acids unique to mature, cross-linked elastin, they are useful for discriminating peptides derived from elastin breakdown from precursor elastin peptides. According to these features, DES and IDES have been extensively discussed as potentially attractive indicators of elevated lung elastic fibre turnover and markers of the effectiveness of agents with the potential to reduce elastin breakdown. In the present manuscript, immunology-based and separation methods for the evaluation of DES and IDES are discussed, along with studies reporting increased levels of urine excretion in chronic obstructive pulmonary disease (COPD) patients with and without alpha(1)-antitrypsin deficiency. The results of the application of DES and IDES as surrogate end-points in early clinical trials in COPD are also reported. Finally, recent advances in detection techniques, including liquid chromatography tandem mass spectrometry and high-performance capillary electrophoresis with laser-induced fluorescence, are discussed. These techniques allow detection of DES and IDES at very low concentration in body fluids other than urine, such as plasma or sputum, and will help the understanding of whether DES and IDES are potentially useful in monitoring therapeutic intervention in COPD.

Topics: Adult; alpha 1-Antitrypsin Deficiency; Child; Chromatography, Liquid; Desmosine; Elastin; Female; Humans; Isodesmosine; Male; Models, Biological; Peptides; Pulmonary Disease, Chronic Obstructive; Smoking; Tandem Mass Spectrometry

Matrix metalloproteinase (MMP)-9 has been consistently identified in the lungs of patients with chronic obstructive pulmonary disease (COPD). However, its role in the development of the disease remains undefined. Mice that specifically express human MMP-9 in their macrophages were generated, and morphometric, biochemical, and histological analyses were conducted on the transgenic and littermate control mice over 1 yr to determine the effect of macrophage MMP-9 expression on emphysema formation and lung matrix content. Lung morphometry was normal in transgenic mice at 2 mo of age (mean linear intercept = 50+/-3 littermate mice vs. 51+/-2 transgenic mice). However, after 12 mo of age, the MMP-9 transgenic mice developed significant air space enlargement (mean linear intercept = 53+/-3 littermate mice vs. 61+/-2 MMP-9 transgenic mice; P<0.04). Lung hydroxyproline content was not significantly different between wild-type and transgenic mice, but MMP-9 did significantly decrease alveolar wall elastin at 1 yr of age (4.9+/-0.3% area of alveolar wall in the littermate mice vs. 3.3+/-0.3% area of alveolar wall in the MMP-9 mice; P<0.004). Thus these results establish a central role for MMP-9 in the pathogenesis of this disease by demonstrating that expression of this protease in macrophages can alter the extracellular matrix and induce progressive air space enlargement in mice.

Topics: Animals; Elastin; Emphysema; Humans; Lung; Matrix Metalloproteinase 9; Mice; Mice, Transgenic; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive

Topics: Collagen; Elastin; Humans; Lung; Pulmonary Disease, Chronic Obstructive; Respiratory Function Tests

COPD is characterised by loss of alveolar elastic fibers and by lack of effective repair. Elastic fibers are assembled at cell surfaces by elastin binding protein (EBP), a molecular chaperone whose function can be reversibility inhibited by chondroitin sulphate of matrix proteoglycans such as versican. This study aimed to determine if alveoli of patients with mild to moderate COPD contained increased amounts of versican and a corresponding decrease in EBP, and if these changes were correlated with decreases in elastin and FEV1.. Lung samples were obtained from 26 control (FEV1 > or = 80% predicted, FEV1/VC >0.7) and 17 COPD patients (FEV1 > or = 40% - <80% predicted, FEV1/VC < or = 0.7) who had undergone a lobectomy for bronchial carcinoma. Samples were processed for histological and immuno-staining. Volume fractions (Vv) of elastin in alveolar walls and alveolar rims were determined by point counting, and versican and EBP assessed by grading of staining intensities.. Elastin Vv was positively correlated with FEV1 for both the alveolar walls (r = 0.66, p < 0.001) and rims (r = 0.41, p < 0.01). Versican was negatively correlated with FEV1 in both regions (r = 0.30 and 0.32 respectively, p < 0.05), with the highest staining intensities found in patients with the lowest values for FEV1. Conversely, staining intensities for EBP in alveolar walls and rims and were positively correlated with FEV1 (r = 0.43 and 0.46, p < 0.01).. Patients with mild to moderate COPD show progressively increased immuno-staining for versican and correspondingly decreased immuno-staining for EBP, with decreasing values of FEV1. These findings may explain the lack of repair of elastic fibers in the lungs of patients with moderate COPD. Removal of versican may offer a strategy for effective repair.

Topics: Aged; Aged, 80 and over; Case-Control Studies; Elastin; Forced Expiratory Volume; Humans; Middle Aged; Pulmonary Alveoli; Pulmonary Disease, Chronic Obstructive; Receptors, Cell Surface; Severity of Illness Index; Versicans

Chronic obstructive pulmonary disease and emphysema are common destructive inflammatory diseases that are leading causes of death worldwide. Here we show that emphysema is an autoimmune disease characterized by the presence of antielastin antibody and T-helper type 1 (T(H)1) responses, which correlate with emphysema severity. These findings link emphysema to adaptive immunity against a specific lung antigen and suggest the potential for autoimmune pathology of other elastin-rich tissues such as the arteries and skin of smokers.

Topics: Autoimmunity; B-Lymphocytes; Elastin; Emphysema; Humans; Lung; Pulmonary Disease, Chronic Obstructive; Smoking; T-Lymphocytes; T-Lymphocytes, Regulatory

Application of mass spectrometry (MS) for direct measurements of desmosine (D) and isodesmosine (I) in urine, plasma, and sputum as markers of elastin degradation in patients with alpha(1)-antitrypsin deficiency (AATD) and non-AATD-related COPD.. In COPD patients, the lungs undergo elastin injury, which can be monitored by measurements of D and I in body fluids as specific markers of elastin degradation using the specificity and sensitivity of MS.. Acid hydrolysis of blood plasma, 24-h urine and sputum measurements, followed by chromatographic separation for mass spectrometric analysis.. Each patient group had levels of plasma D and I that were statistically significantly higher than those of control subjects. AATD patients had higher levels than COPD patients with normal alpha(1)-antitrypsin (AAT) levels. Twenty-four-hour urine measurements demonstrated no significant difference in total levels of D and I among control subjects and patients but showed a free (unbound) concentration of D and I in urine, which was statistically significantly higher in patients with COPD with and without AAT. The D and I levels in the sputum of patients with AATD exceeded the levels in COPD patients with normal AAT levels.. MS allows a sensitive and specific analysis of D and I in body fluids. The quantification of D and I in sputum, along with increases of D and I in plasma and an elevated free component of D and I in urine provide indexes that characterize patients with COPD and can be followed in relation to the course of the disease and/or therapy.

Topics: Adult; Aged; Aged, 80 and over; alpha 1-Antitrypsin Deficiency; Desmosine; Elastin; Female; Humans; Isodesmosine; Male; Mass Spectrometry; Matched-Pair Analysis; Middle Aged; Prognosis; Pulmonary Disease, Chronic Obstructive; Sensitivity and Specificity; Sputum

Topics: Elastin; Eosinophilia; Humans; Matrix Metalloproteinases; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema

The production of the inflammatory cytokine interleukin (IL)-1 is increased in lungs of patients with chronic obstructive pulmonary disease (COPD) or asthma. To characterize the in vivo actions of IL-1 in the lung, transgenic mice were generated in which human IL-1beta was expressed in the lung epithelium with a doxycycline-inducible system controlled by the rat Clara cell secretory protein (CCSP) promoter. Induction of IL-1beta expression in the lungs of adult mice caused pulmonary inflammation characterized by neutrophil and macrophage infiltrates. IL-1beta caused distal airspace enlargement, consistent with emphysema. IL-1beta caused disruption of elastin fibers in alveolar septa and fibrosis in airway walls and in the pleura. IL-1beta increased the thickness of conducting airways, enhanced mucin production, and caused lymphocytic aggregates in the airways. Decreased immunostaining for the winged helix transcription factor FOXA2 was associated with goblet cell hyperplasia in IL-1beta-expressing mice. The production of the neutrophil attractant CXC chemokines KC (CXCL1) and MIP-2 (CXCL2), and of matrix metalloproteases MMP-9 and MMP-12, was increased by IL-1beta. Chronic production of IL-1beta in respiratory epithelial cells of adult mice causes lung inflammation, enlargement of distal airspaces, mucus metaplasia, and airway fibrosis in the adult mouse.

Topics: Animals; Asthma; Base Sequence; Bronchoalveolar Lavage Fluid; Chemokines, CXC; Collagen; Disease Models, Animal; DNA, Complementary; Elastin; Gene Expression; Humans; Inflammation; Interleukin-1; Lymphocytes; Matrix Metalloproteinases; Mice; Mice, Transgenic; Organ Size; Organ Specificity; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Respiratory System; RNA, Messenger; Tumor Necrosis Factor-alpha

We describe a novel variant in the terminal exon of human elastin, c.2318 G > A, resulting in an amino acid substitution of glycine 773 to aspartate (G773D) in a pedigree with severe early-onset chronic obstructive pulmonary disease (COPD). Transfection studies with elastin cDNAs demonstrate that the glycine to aspartate change compromises the ability of the mutant protein to undergo normal elastin assembly. Other functional consequences of this amino acid substitution include altered proteolytic susceptibility of the C-terminal region of elastin and reduced interaction of the exon 36 sequence with matrix receptors on cells. These results suggest that the G773D variant confers structural and functional consequences relevant to the pathogenesis of COPD.

Topics: Alternative Splicing; Amino Acid Sequence; Amino Acid Substitution; Animals; Cattle; Cell Adhesion; Cells, Cultured; DNA Mutational Analysis; Elastin; Exons; Female; Humans; Male; Middle Aged; Molecular Sequence Data; Multicenter Studies as Topic; Pedigree; Polymorphism, Genetic; Pulmonary Disease, Chronic Obstructive; Randomized Controlled Trials as Topic; Tropoelastin

To measure serum concentrations of elastin-derived peptides (S-EDP) in patients with aneurysmal, occlusive and ulcerative manifestations of atherosclerotic disease.. S-EDP concentrations were measured by a competitive enzyme-linked immunosorbent assay in 10 patients with infrarenal aneurysms 5cm in diameter (AAA), 10 patients with distal aortic occlusive disease (AOD), 10 patients with symptomatic carotid stenosis (>or=70%) and plaque ulceration (SCS) and a control group of 10 patients with no similar specific manifestations of atherosclerotic disease (NAM).. S-EDP concentrations (median, range) were significantly higher in patients with AAA (42ng/ml, 35-52, p<0.001) and SCS (49ng/ml, 37-60, p<0.001) but not AOD (28ng/ml, 22-38, p=0.240) compared to NAM (26ng/ml, 19-36) patients.. Increased concentrations of S-EDP were associated with aneurysmal and ulcerative, but not occlusive, manifestations of atherosclerosis.

Topics: Aged; Aged, 80 and over; Analysis of Variance; Aortic Aneurysm, Abdominal; Aortic Diseases; Arterial Occlusive Diseases; Arteriosclerosis; Carotid Stenosis; Elastin; Enzyme-Linked Immunosorbent Assay; Female; Humans; Male; Middle Aged; Peptides; Pulmonary Disease, Chronic Obstructive; Smoking; Statistics, Nonparametric

Desmosine (DES) is an elastin-derived, cross-link amino acid, which is not metabolized; hence, its urinary levels reflect elastin breakdown. We hypothesized that elastin degradation should increase as a result of increased lung inflammation during an acute exacerbation of COPD and should decrease after recovery. To test this hypothesis we measured DES in three urine samples from nine COPD subjects during the first 5 days of an acute exacerbation and at 2 months after recovery. We also measured forced expiratory volume in 1 sec (FEV1) to monitor the effects ofthe exacerbation on ventilatory function. The mean (SD) FEV1 was 45 (15)% predicted during the exacerbation and 57.8 (16)% predicted 2 months later (P=0.00001). The mean (SD) DES excretion was 25.3 (9) microg g(-1) creatinine at day 1;23.5 (9) at day 3 and 24 (9) at day 5 of the exacerbation. The mean (SD) urinary DES excretion 60 days after discharge was 20.9 (7) microg g(-1) creatinine (P=0.049) in comparison with the mean of the three acute-phase values. The size of the increase in desmosine excretion during exacerbation is small, 3.2 microg g(-1) creatinine or 16% of the recovery desmosine value. We conclude that there is a small but statistically significant increase in lung elastin breakdown in the body during an acute exacerbation of COPD.

Topics: Acute Disease; Aged; Analysis of Variance; Biomarkers; Chromatography, Micellar Electrokinetic Capillary; Desmosine; Elastin; Forced Expiratory Volume; Humans; Longitudinal Studies; Male; Middle Aged; Pulmonary Disease, Chronic Obstructive

Intimal enlargement of pulmonary arteries is an early change in chronic obstructive pulmonary disease (COPD). The cellular and extracellular components that are involved in this enlargement are unknown. The present study was designed to characterize the structural changes occurring in pulmonary muscular arteries in the initial disease stages. Lung specimens from patients with moderate COPD (n=8; forced expiratory volume in one second (FEV1), 66 +/- 10% predicted) and smokers without airflow obstruction (n=7; FEV1, 86 +/- 6% pred), were investigated by histochemistry to characterize extracellular matrix proteins and by immunohistochemistry to identify intrinsic cells of the vascular wall. In both COPD patients and smokers, the majority of cells present in the enlarged intimas were stained by specific smooth muscle cell (SMC) markers. No staining with endothelial or fibroblast markers was shown. A proportion of SMCs did not stain with desmin, suggesting cellular heterogeneity in this population. Elastin was the most abundant extracellular matrix protein and collagen was seen in a lower proportion. The amount of collagen was related to the intimal thickness (p<0.001). The findings demonstrated smooth muscle cell proliferation, as well as elastin and collagen deposition, in the thickened intimas of pulmonary arteries in moderate chronic obstructive pulmonary disease patients and smokers, suggesting that these abnormalities may originate at an early stage in cigarette smoke-induced respiratory disease.

Topics: Aged; Collagen; Elastin; Extracellular Matrix Proteins; Humans; Immunohistochemistry; Male; Middle Aged; Muscle, Smooth, Vascular; Pulmonary Artery; Pulmonary Disease, Chronic Obstructive; Smoking; Tunica Intima