Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034067 (emphysema)
11,506 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

As a result of improved diagnosis, treatment, and supportive care for HIV-infected patients, AIDS in developed countries has now become a chronic infection with prolonged survival time, but longterm complications are increasing contributors to morbidity and mortality. HIV-infected patients are at increased risk for the development of pulmonary complications, including chronic obstructive pulmonary disease (COPD); however, the mechanisms associated with this increased susceptibility have not been defined. Infectious agents may contribute to the development of COPD by upregulating inflammatory mediators in the lung that act in concert with cigarette smoke to promote lung pathology. Studies in human subjects and non-human primate models of AIDS suggest that the inflammatory response to asymptomatic carriage or colonization by the opportunistic pathogen, Pneumocystis sp. (Pc), is similar to that of COPD, which is characterized by influx of CD8+ T cells, neutrophils, and macrophages into the lungs. We have shown a high frequency of Pc colonization among asymptomatic HIV-infected subjects and in non-HIV infected subjects with COPD. To investigate the role of Pc in the progression of obstructive lung disease in HIV infections, we developed a non-human primate model of Pc colonizatoin and infection in simian immunodeficiency virus (SIV)-infected macaques. These animals develop a prolonged colonization state characterized by a persistent influx of CD8+ T cells and neutrophils, and local increases in IL-8, IFN-gamma, and TNF-alpha. SIV-infected Pc-colonized monkeys show progressive decline in pulmonary function compared to SIV-infected monkeys. We hypothesize that in the context of AIDS-immune dysfunction, Pc colonization induces inflammatory responses leading to changes in pulmonary function and architecture similar to that seen in emphysema. Information gained from these studies will lead to the development of interventions to prevent lung injury associated with Pc colonization and the development of HIV-associated COPD.
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PMID:Pneumocystis colonization, airway inflammation, and pulmonary function decline in acquired immunodeficiency syndrome. 1733 78

Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease associated with progressive airflow obstruction. Tobacco smoking is the main risk factor worldwide. In contrast to asthma, antiinflammatory therapies are rather ineffective in improving chronic symptoms and reducing inflammation, lung function decline, and airway remodeling. Specific drugs that are directed against the remodeling and chronic inflammation, thereby preventing lung tissue damage and progressive lung function decline, must be developed. Experimental models and expression studies suggest that anti-vascular endothelial growth factor (VEGF) receptor strategies may be of use in patients with emphysema, whereas anti-HER1-directed strategies may be more useful in patients with pulmonary mucus hypersecretion, as seen in chronic bronchitis and asthma. Growth factors and cytokines including VEGF, fibroblast growth factors, transforming growth factor-beta, tumor necrosis factor-alpha, CXCL1, CXCL8, and CCL2, and signal transduction proteins such as mitogen-activated protein kinase p38 and nuclear factor-kappaB, seem to be important pathogenetic molecules in COPD. Specific antagonists for these proteins may be effective for different inflammatory diseases. However, their efficacy for COPD therapy has not yet been demonstrated. Finally, other drugs such as retinoic acids may provide restoration of lung tissue structure. Such approaches, however, must await the first results of growth factor or cytokine antagonist therapy in chronic lung diseases.
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PMID:Molecular mechanisms in chronic obstructive pulmonary disease: potential targets for therapy. 1740 66

Endothelin (ET) receptor antagonists have been developed to produce a reduction of ET related effects in various diseases, as well as in animal models of airway inflammation. We aimed to investigate the anti-inflammatory potential of bosentan on a rat model of emphysema. Thirty Wistar male rats were classified as control group (group 1), intratracheally (i.t.) instilled with saline, treated with vehicle solution; elastase group (group 2), i.t. instilled with porcine pancreatic elastase (PPE), treated with vehicle solution; and PPE+bosentan group (group 3), i.t. instilled with PPE, treated with bosentan. The levels of TNF-alpha, IL-1beta, IL-6, and IL-8 in bronchoalveolar lavage fluid (BALF) and lung tissue, cell counts in BALF, and histologic analysis of all groups were evaluated. Neutrophile granulocytes (NG) and alveolar macrophages (AM) were increased more in group 2 than in group 1 (P<0.001, P=0.04, respectively). Compared with group 2, neutrophil granulocyte (NG) and alveolar macrophages (AM) counts were decreased in group 3 (P<0.001). Histological examination confirmed a diffuse neutrophilic inflammation and irregular alveolar air space enlargement in group 2. Treatment with bosentan partially reduced the enlarged lung volumes. Compared with group 1, the BALF levels of TNF-alpha and IL-6, and the lung tissue levels of IL-1beta, IL-6, and IL-8 were increased in group 2 (P=0.028, P=0.005, P=0.001, P=0.019, P<0.001, respectively). The TNF-alpha and IL-8 levels of BALF (P=0.007, P=0.001, respectively), and the TNF-alpha, IL-1beta, IL-6, and the IL-8 levels of lung tissue (P=0.031, P=0.017, P=0.007, P<0.001) were decreased in group 3 compared to group 2. In conclusion, bosentan decreased the inflammatory response by reducing numbers of inflammatory cells and proinflammatory cytokines.
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PMID:Effect of bosentan on the production of proinflammatory cytokines in a rat model of emphysema. 1805 37

Chronic obstructive pulmonary disease (COPD) is characterized by an abnormal persistent inflammatory response to cigarette smoke. This noxious insult leads to emphysema and airway remodeling, manifested by squamous and mucous metaplasia of the epithelium, smooth muscle hypertrophy, and airway wall fibrosis. These pathologic abnormalities interact synergistically to cause progressive airflow obstruction. Although it has been accepted that the spectrum of COPD is vast, the reasons for the development of different phenotypes from the same exposure to cigarette smoke have not been determined. Furthermore, it is becoming increasingly clear that airways disease and emphysema often coexist in many patients, even with a clear clinical phenotype of either emphysema or chronic bronchitis. Recent studies have focused on the nature of the inflammatory response to cigarette smoke, the inflammatory cell lines responsible for COPD pathogenesis, and new biomarkers for disease activity and progression. New cytokines are being discovered, and the complex interactions among them are being unraveled. The inflammatory biomarker that has received the most attention is C-reactive protein, but new ones that have caught our attention are interleukin (IL)-6, tumor necrosis factor-alpha, IL-8, and IL-10. Further research should focus on how these new concepts in lung inflammation interact to cause the various aspects of COPD pathology.
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PMID:New concepts in the pathobiology of chronic obstructive pulmonary disease. 1845 59

Chronic airway inflammation is a cardinal feature of chronic obstructive pulmonary disease (COPD), a destructive cigarette smoke-induced lung disease. Although it is apparent that dendritic cells (DCs) are an important constituent of the chronic inflammatory cell influx found in airways of COPD patients, the functional roles of DCs in the pathogenesis of smoking-induced emphysema are unknown. We postulated that DCs activated by cigarette smoke constituents directly participate in the chronic inflammation that characterizes COPD airways. Concordant with this hypothesis, we observed that incubation of DCs with cigarette smoke extract (CSE), and chronic exposure of mice to cigarette smoke, both augmented the generation of neutrophilic chemokines by immature and lipopolysaccharide (LPS) or CD40L-matured DCs. The generation of interleukin-8 (CXCL8/IL-8) by human DCs conditioned with CSE was suppressed by the anti-oxidant n-acetyl cysteine (NAC), implying the involvement of oxidant sensitive pathways as a primary mechanism involved in the enhanced CXCL8/IL-8 generation. Cigarette smoke extract and nicotine also augment the production of secreted prostaglandin-E2 and intra-cellular cyclo-oxygenase-2 (COX-2) in maturing DCs. Whereas NAC suppressed production of CXCL8 by CSE-conditioned DCs, it augmented production of PGE2 and cellular COX-2 levels in maturing DCs. These studies indicate that the stimulation of DCs by cigarette smoke-induced oxidative stress and nicotine promote the generation of pro-inflammatory responses that promote chronic inflammation in smokers. Certain pharmacologic strategies such as anti-oxidant therapy may be only partially effective in mitigating cigarette smoke-induced pro-inflammatory DC-mediated responses in smokers.
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PMID:Nicotine and oxidative cigarette smoke constituents induce immune-modulatory and pro-inflammatory dendritic cell responses. 1853 67

We screened bronchoalveolar lavage (BAL) fluids from COPD-E (chronic obstructive pulmonary disease-Emphysema) and control subjects using a 120 Ab cytokine array and demonstrated that adiponectin was highly expressed in BAL in COPD-E. An adiponectin ELISA confirmed that adiponectin was highly expressed in BAL in COPD-E compared with smokers and healthy control subjects. Immunohistochemistry studies of lung sections from subjects with COPD-E demonstrated that airway epithelial cells expressed significant levels of adiponectin and adiponectin receptor (AdipoR) 1 but not AdipoR2. In vitro studies with purified populations of human lung A549 epithelial cells demonstrated that they expressed both adiponectin and AdipoR1 (but not AdipoR2) as assessed by RT-PCR, Western blot, and immunohistochemistry. Lung A549 epithelial AdipoR1were functional as incubation with adiponectin induced release of IL-8, which was inhibited by small interfering RNA to AdipoR1. Using a mouse model of COPD, tobacco smoke exposure induced both evidence of COPD as well as increased levels of adiponectin in BAL fluid and increased adiponectin expression by airway epithelial cells. As adiponectin expression in adipocytes is dependent upon NF-kappaB we determined levels of adiponectin in tobacco smoke exposed CC10-Cre(tg)/Ikkbeta(Delta/Delta) mice (deficient in the ability to activate NF-kappaB in airway epithelium). These studies demonstrated that CC10-Cre(tg)/Ikkbeta(Delta/Delta) and wild-type mice had similar levels of BAL adiponectin and airway epithelial adiponectin immunostaining. Overall, these studies demonstrate the novel observation that adiponectin and functional AdipoR1are expressed by lung epithelial cells, suggesting a potential autocrine and/or paracrine pathway for adiponectin to activate epithelial cells in COPD-E.
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PMID:Adiponectin and functional adiponectin receptor 1 are expressed by airway epithelial cells in chronic obstructive pulmonary disease. 1910 2

alpha(1)-Antitrypsin (AT) is a major elastase inhibitor within the lung. Oxidation of critical methionine residues in AT generates oxidized AT (Ox-AT), which has a greatly diminished ability to inhibit neutrophil elastase. This process may contribute to the pathogenesis of chronic obstructive pulmonary disease (COPD) by creating a functional deficiency of AT permitting lung destruction. We show here that Ox-AT promotes release of human monocyte chemoattractant protein-1 (MCP-1) and IL-8 from human lung type epithelial cells (A549) and normal human bronchial epithelial (NHBE) cells. Native, cleaved, polymeric AT and secretory leukoproteinase inhibitor (SLPI) and oxidized conformations of cleaved, polymeric AT and SLPI did not have any significant effect on MCP-1 and IL-8 secretion. These findings were supported by the fact that instillation of Ox-AT into murine lungs resulted in an increase in JE (mouse MCP-1) and increased macrophage numbers in the bronchoalveolar lavage fluid. The effect of Ox-AT was dependent on NF-kappaB and activator protein-1 (AP-1)/JNK. These findings have important implications. They demonstrate that the oxidation of methionines in AT by oxidants released by cigarette smoke or inflammatory cells not only reduces the antielastase lung protection, but also converts AT into a proinflammatory stimulus. Ox-AT generated in the airway interacts directly with epithelial cells to release chemokines IL-8 and MCP-1, which in turn attracts macrophages and neutrophils into the airways. The release of oxidants by these inflammatory cells could oxidize AT, perpetuating the cycle and potentially contributing to the pathogenesis of COPD. Furthermore, these data demonstrate that molecules such as oxidants, antiproteinases, and chemokines, rather than act independently, are likely to interact to cause emphysema.
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PMID:Oxidized {alpha}1-antitrypsin stimulates the release of monocyte chemotactic protein-1 from lung epithelial cells: potential role in emphysema. 1952 88

Extracellular ATP is a signaling molecule that often serves as a danger signal to alert the immune system of tissue damage. This molecule activates P2 nucleotide receptors, that include the ionotropic P2X receptors and metabotropic P2Y receptors. Recently, it has been reported that ATP accumulates in the airways of both asthmatic patients and sensitized mice after allergen challenge. The role and function of ATP in the pathogenesis of chronic obstructive pulmonary diseases (COPD) are not well understood. In this study we investigated the effect of cigarette smoke on purinergic receptors and ATP release by neutrophils. Neutrophils and their mediators are key players in the pathogenesis of lung emphysema. Here we demonstrated that in an in vivo model of cigarette smoke-induced lung emphysema, the amount of ATP was increased in the bronchoalveolar lavage fluid. Moreover, activation of neutrophils with cigarette smoke extract induced ATP release. Treatment of neutrophils with apyrase (catalyses the hydrolysis of ATP to yield AMP) and suramin (P2-receptor antagonist) abrogated the release of CXCL8 and elastase induced by cigarette smoke extract and exogenous ATP. These observations indicate that activation of purinergic signaling by cigarette smoke may take part in the pathogenesis of lung emphysema.
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PMID:ATP in the pathogenesis of lung emphysema. 1965 6

Macrophages are key inflammatory cells in chronic obstructive pulmonary disease (COPD). The pathophysiology of cigarette smoke-induced lung emphysema is complex but there is a clear role for reactive oxygen species (ROS, such as peroxynitrite), tumor necrosis factor (TNF-alpha) and interleukin (IL)-8. We investigated whether TNF-alpha or cigarette smoke medium (CSM) alone or in combination induces the production of IL-8 by human macrophages or monocyte lymphoma U937. CSM and TNF-alpha induce a dose- and time-dependent increase in IL-8 production. Interestingly, when sub-threshold concentrations of CSM and TNF-alpha were co-incubated, a 1500% increase in IL-8 production was observed compared to either of the compounds alone. Similar results were obtained with TNF-alpha and the peroxynitrite donor SIN-1. Moreover, the overproduction of IL-8 was associated with an enhanced increase in the translocation of NF-kappaB and an enhanced decrease in glutathione levels. Preincubation of the cells with antioxidants, such as N-acetyl-L-cysteine (NAC), prevented the overproduction of IL-8 and activation of NF-kappaB. In conclusion, CSM exposure of macrophages up-regulates the expression and the production of IL-8 via reactive oxygen species and NF-kappaB activation. Moreover, CSM dramatically enhances the production of IL-8 in combination with TNF-alpha. Based upon the strong synergistic action, a combination therapy directed against ROS and TNF-alpha could be a new approach to stop the progression in lung damage during emphysema.
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PMID:IL-8 production by macrophages is synergistically enhanced when cigarette smoke is combined with TNF-alpha. 1987

Chronic obstructive pulmonary disease (COPD) is characterized by chronic airway inflammation and emphysematous alveolar destruction. In this study, we have investigated whether chitotriosidase (ChTRase) and acidic mammalian chitinase, two chitinases with chitinolytic activity, are selectively augmented in COPD and contribute to its pathogenesis. We found that smokers with COPD, but not asthmatics, had higher chitinolytic activity and increased levels of ChTRase in bronchoalveolar lavage, more ChTRase-positive cells in bronchial biopsies, and an elevated proportion of alveolar macrophages expressing ChTRase than smokers without COPD or never-smokers. ChTRase accounted for approximately 80% of bronchoalveolar lavage chitinolytic activity, while acidic mammalian chitinase was undetectable. Bronchoalveolar lavage chitinolytic activity and ChTRase were associated with airflow obstruction and emphysema and with the levels of interleukin (IL)-1beta, IL-8, tumor-necrosis factor (TNF)-alpha, and its type II soluble receptor. Tumor necrosis factor-alpha stimulated ChTRase release only from alveolar macrophages from smokers with COPD, and exposure of these cells to ChTRase promoted the release of IL-8, monocyte-chemoattractant protein-1, and metalloproteinase-9. Finally, ChTRase overexpression in the lung of normal mice promoted macrophage recruitment and the synthesis of the murine homologue of IL-8, keratinocyte-derived cytokine, and of monocyte-chemoattractant protein-1. We conclude that pulmonary ChTRase overexpression may represent a novel important mechanism involved in COPD onset and progression.
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PMID:Lung chitinolytic activity and chitotriosidase are elevated in chronic obstructive pulmonary disease and contribute to lung inflammation. 2004 71


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