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)

Toxic oxygen free radicals are believed to play a role in the pathogenesis of a number of respiratory diseases. In particular, pulmonary emphysema may occur because of the oxidative impairment of alpha 1-proteinase inhibitor (alpha 1-PI). We report in vitro data on a new thiol agent, P 1507 [N-5-(thioxo-L-prolyl)-L-cysteine], obtained in a series of experiments designed in view of its therapeutic potential in these clinical conditions. We found that P 1507 at the concentration of 5 x 10(-6) M was able to almost fully abolish the PMA-triggered PMN-induced oxidative impairment of alpha 1-PI. Protection may be due to the radical scavenger ability of P 1507, that markedly reduced superoxide anion production from PMNs. We also found that P 1507 did not significantly impair other defence mechanisms of PMNs (i.e. phagocytosis, chemotaxis and bactericidal activity). The release of cytokines (TNF-alpha, IL-6 and IL-8) from monocytes was not altered in the presence of P 1507. We conclude that the compound P 1507 may be considered for treatment of clinical conditions characterized by overload of oxidants, on the basis of its ability in preventing the oxidative damage of alpha 1-PI and of a lack of unwanted inhibitory effects towards defence mechanisms of phagocytes.
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PMID:Interactions of P 1507, a new antioxidant agent, with phagocyte functions. 774 Oct 36

The effect of repeated doses of TNF-alpha on the histological picture of the pulmonary tissue was analyzed in the present study. Special attention was paid to the lung rebuilding processes. TNF-alpha was applied intraperitoneally for two weeks in a dose of 10 micrograms/0.5 ml PBS/24h. Morphological analysis of the pulmonary tissue was performed after 1 and 28 days following the last TNF-alpha dose. The study revealed focal pulmonary tissue rebuilding with emphysema-like changes twenty eight days following termination of TNF-alpha administration. The rebuilding processes included interalveolar septal atrophy, collagen accumulation and damage-repair changes in type II alveolar epithelial cells. It has been demonstrated that apart from the protease-antiprotease hypothesis of the lung emphysema, the inflammatory-repair hypothesis should be considered. Both hypotheses are complementary to each other and interpret the emphysema-like changes as complications of various pathological conditions of the pulmonary tissue.
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PMID:Tumor necrosis factor-alpha induces emphysema-like pulmonary tissue rebuilding. Changes in type II alveolar epithelial cells. 940 11

Cystic fibrosis (CF) is an inherited disorder associated with severe inflammation and repeated bacterial infection and colonization in the lung. Airway epithelium is involved in defence against bacteria, but this system may be defective in CF. Pro-inflammatory cytokines can stimulate the expression of inducible nitric oxide synthase (iNOS), an enzyme generating nitric oxide, which functions as an important mediator in host defence mechanisms. To understand better the poor resistance to infections in the CF lung, the expression of the iNOS gene was investigated in explanted lungs from patients with cystic fibrosis (n = 13), bronchiectasis (n = 3), emphysema (n = 14), and in normal lungs (n = 8). In addition, bronchial epithelial cell lines were examined to study iNOS gene expression in vitro. Strong immunoreactivity for iNOS was seen in inflammatory cells and bronchial epithelium in all the diseased lungs, except for bronchial epithelium in CF. Quantitative analysis showed a significant reduction in the area of epithelium immunostained in CF [CF 6.8 +/- 1.6 (% +/- SEM); emphysema 18.2 +/- 2.8; normal 9.6 +/- 0.8, P < 0.01], regardless of steroid treatment. These results were supported by in situ hybridization of iNOS mRNA, which showed a pattern of gene expression in CF, emphysema, and normal lung which paralleled that of protein immunoreactivity. Stimulation with cytokines (IL-1 beta, TNF-alpha, and IFN-gamma) increased the expression of iNOS mRNA detected by reverse transcriptase-polymerase chain reaction (RT-PCR) in cultures of normal (16HBE14o-), but not CF (CFBE41o-, with delta F508 CFTR mutation) epithelial cells. Expression of iNOS in inflammatory cells suggests that the gene is normal in CF. Absence of iNOS from bronchial epithelium may be due to low expression of the gene resulting from abnormalities in the signalling system that normally causes induction, such as cytokine receptors, second messengers or transcription factors. The resulting deficiency of the nitric oxide defence system may be relevant to the susceptibility of CF patients to pulmonary bacterial colonization.
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PMID:Lack of inducible nitric oxide synthase in bronchial epithelium: a possible mechanism of susceptibility to infection in cystic fibrosis. 961 86

Tumour necrosis factor(TNF)-alpha levels are elevated in airways of patients with chronic obstructive pulmonary disease (COPD) and may contribute to its pathogenesis. A guanine to adenine substitution at position -308 of the TNF-alpha gene promoter (TNF1/2) has been associated with chronic bronchitis of various aetiologies in a Taiwanese population. The authors performed a study investigating association of the polymorphism with smoking-related COPD in Caucasians. Frequencies of TNF1/2 alleles in 86 Caucasians (52 males) with COPD were compared with 63 (52 males) asymptomatic smoker/exsmoker control subjects and a population control of 199 (99 males) blood donors. Genotyping was performed by the polymerase chain reaction-restriction fragment length polymorphism technique on genomic deoxyribonucleic acid (DNA) obtained from peripheral blood. There were no significant differences in TNF1/2 allele frequencies between groups: 0.85/0.15 in COPD, 0.85/0.15 in smoker control subjects, 0.83/0.17 in population control subjects. Within the COPD group there was no association of TNF1/2 alleles with indices of airflow obstruction (% predicted forced expiratory volume in one second (FEV1) and % predicted FEV1/vital capacity ratio) nor gas transfer (% predicted carbon monoxide transfer coefficient and % predicted carbon monoxide diffusing capacity of the lung). It is concluded that: 1) the tumour necrosis factor gene promoter allele does not influence the risk of developing chronic obstructive pulmonary disease in a Caucasian population of smokers; and 2) there is no association of the tumour necrosis factor gene promoter genotype with severity of airflow obstruction nor degree of emphysema in chronic obstructive pulmonary disease.
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PMID:Tumour necrosis factor-alpha gene promoter polymorphism in chronic obstructive pulmonary disease. 1070 92

An imbalance between proteases and antiproteases may play a role in emphysema, which is characterized by increased degradation of extracellular matrix, and in airway remodeling in chronic bronchitis and asthma, in which there is increased collagen deposition. We assessed the effect of smoking on release of matrix metalloprotease-9 (MMP-9) and of its inhibitor, tissue inhibitor of metalloprotease-1 (TIMP-1), from alveolar macrophages, and determined the effects of proinflammatory (interleukin [IL]-1beta and lipopolysaccharide [LPS]) and antiinflammatory (IL-10) stimuli on the release of MMP-9 and TIMP-1. We performed bronchoalveolar lavage in 11 smokers and 11 nonsmokers, and cultured airway macrophages in the presence of control medium, IL-1beta, and LPS. Airway macrophages from smokers released greater amounts of MMP-9 and TIMP-1 at baseline and in response to IL-1beta and LPS than did those of nonsmokers. Airway macrophages from smokers produced more TNF-alpha and IL-10. IL-10 increased TIMP-1 release without modifying that of MMP-9, leading to a decrease in the MMP-9 to TIMP-1 ratio. Anti-IL-10 antibody had no effect on MMP-9 production induced by LPS. We conclude that the release of proteases and antiproteases by airway macrophages is increased in cigarette smokers, and can be regulated by exogenous IL-10.
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PMID:Balance of matrix metalloprotease-9 and tissue inhibitor of metalloprotease-1 from alveolar macrophages in cigarette smokers. Regulation by interleukin-10. 1102 44

Tumor necrosis factor (TNF)-alpha is a key proinflammatory cytokine that is thought to be important in the development of pulmonary fibrosis, whereas its role in pulmonary emphysema has not been as thoroughly documented. In the present study, TNF-alpha was overexpressed in alveolar type II cells under the control of the human surfactant protein C promoter. In this report, we further characterized the pulmonary abnormalities and provided a physiological assessment of these mice. Histopathology of the lungs revealed chronic inflammation, severe alveolar air space enlargement and septal destruction, and bronchiolitis. However, pulmonary fibrosis was very limited and only seen in the subpleural, peribronchiolar, and perivascular regions. Physiological assessment showed an increase in lung volumes and a decrease in elastic recoil characteristic of emphysema; there was no evidence of restrictive lung disease characteristic of pulmonary fibrosis. In addition, the mice raised in ambient conditions in Denver developed pulmonary hypertension. Gelatinase activity was increased in the lavage fluid from these lungs. These results suggest that in these mice TNF-alpha contributed to the development of pulmonary emphysema through chronic lung inflammation and activation of the elastolytic enzymes but by itself was unable to produce significant pulmonary fibrosis.
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PMID:Overexpression of tumor necrosis factor-alpha produces an increase in lung volumes and pulmonary hypertension. 1113 93

Exposure to airborne endotoxin in infancy may protect against asthma by promoting enhanced T(H)1 response and tolerance to allergens. On the other hand, later in life, it adversely affects patients with asthma. Endotoxin binding to receptors on macrophages and other cells generates IL-12, which inhibits IgE responses. It also generates cytokines like IL-1, TNF-alpha, and IL-8, which cause inflammation. These signal transduction pathways resemble those leading to the generation of cytokines, such as IL-4, IL-13, and IL-5, which are responsible for the inflammation of IgE-mediated allergic disease. The main difference seems to be that endotoxin recruits neutrophils, but IgE recruits eosinophils, and the details of the tissue injury from these granulocytes differ. Sources of airborne endotoxin include many agricultural dusts, aerosols from contaminated water in many industrial plants, contaminated heating and air-conditioning systems, mist-generating humidifiers, and damp or water-damaged homes. Acute inhalation of high concentrations of endotoxin can cause fever, cough, and dyspnea. Chronic inhalation of lesser amounts causes chronic bronchitis and emphysema and is associated with airway hyperresponsiveness. Airborne endotoxin adversely affects patients with asthma in 3 ways: (1) by increasing the severity of the airway inflammation; (2) by increasing the susceptibility to rhinovirus-induced colds; and (3) by causing chronic bronchitis and emphysema with development of irreversible airway obstruction after chronic exposure of adults. The most effective management is mitigating exposure. The potential of drug treatments requires further clinical investigation.
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PMID:Endotoxin-stimulated innate immunity: A contributing factor for asthma. 1149 29

Proteolytic degradation of extracellular matrix is thought to play an important role both in emphysema and in tissue development and repair. Retinoic acid has been suggested to modify tissue injury, and in an animal model of emphysema may induce alveolar repair. Since cytokines can induce matrix metalloproteinase (MMP) production in fibroblasts and neutrophil elastase (NE) can activate MMPs, we hypothesized that retinoic acid could attenuate collagen degradation by modifying MMP production and activation. To evaluate this, human lung fibroblasts were cast into native type I collagen gels and floated in medium containing cytomix (TNF-alpha, IL-1beta, and IFN-gamma) alone or in combination with NE in the presence and absence of retinoic acid (1 microM). After 5 d, cytomix with elastase induced significant degradation of the collagen gels assessed by quantifying total hydroxyproline (41.6 +/- 1.6 microg versus 3.3 +/- 1.5 microg, P < 0.01). Retinoic acid significantly inhibited this degradation (23.3 +/- 1.5 microg versus 3.3 +/- 1.5 microg, P < 0.01). Gelatin zymography and Western blot revealed that MMP-1, MMP-3, and MMP-9 were induced by cytomix and that co-exposure to NE resulted in increased production of activated forms of these enzymes. Retinoic acid attenuated the induction and activation of MMP-1 and MMP-3. The current study, therefore, suggests that in addition to stimulating anabolic effects, retinoic acid may modulate proteolytic processes thought to contribute to tissue destruction in emphysema.
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PMID:Retinoic acid attenuates cytokine-driven fibroblast degradation of extracellular matrix in three-dimensional culture. 1171 5

A single intratracheal dose of porcine pancreatic elastase, which is cleared from the lung by 24 hours, was administered to wild-type, IL-1beta type 1 receptor-deficient, double TNF-alpha (type 1 and type 2) receptor-deficient, and combined TNF-alpha (type 1 receptor) plus IL-1beta receptor-deficient mice. The mean linear intercept (Lm) of saline-treated mice was 32(3) microm [mean(SE)]. For wild-type elastase-treated mice, Lm was 81(6) microm at 21 days versus 52(5) microm at 5 days after treatment, indicating that alveolar wall remodeling occurs long after the elastase injury. At 21 days, Lm values were 67(10), 62(3), and 39(5) microm in elastase-treated mice deficient in the IL-1beta receptor, double TNF-alpha receptors, and combined receptors, respectively. The level of apoptosis assessed by a terminal deoxynucleotidyl transferase-catalyzed in situ nick end-labeling assay was increased at 5 days after elastase treatment and was markedly and similarly attenuated in the IL-1beta, the double TNF-alpha, and the combined receptor-deficient mice. Our results indicate that inflammatory mediators exacerbate elastase-induced emphysema. We estimate that in the combined TNF-alpha + IL-1beta receptor-deficient mice, inflammation accounts for about 80% of the emphysema that develops after elastase treatment; decreased apoptosis of lung cells likely contributes to decreased severity of emphysema.
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PMID:Severity of elastase-induced emphysema is decreased in tumor necrosis factor-alpha and interleukin-1beta receptor-deficient mice. 1179 28

Tissue destruction, resulting in emphysema, can be a consequence of several pathologic processes. The current study evaluated the effects of the phosphodiesterase (PDE)4 inhibitor, cilomilast, and other PDE inhibitors on the ability of fibroblasts to degrade extracellular matrix. Using the three-dimensional collagen gel culture system, fibroblasts (HFL-1) were cultured with tumor necrosis factor (TNF)-alpha, known to induce matrix metalloproteinase (MMP) release, and/or neutrophil elastase (NE), which can induce MMP activation. On Day 4, gels containing TNF-alpha and NE were significantly degraded (20.8 +/- 2.9% of original collagen content). Cilomilast (10 micro M) inhibited this degradation (84.4 +/- 8.4%). Amrinone, a PDE3 inhibitor, and zaprinast, a PDE5 inhibitor, had no effect. Gelatin zymography and immunoblotting revealed that fibroblasts cultured with TNF-alpha released increased amounts of latent MMP-1 and -9. The addition of NE resulted in the conversion of MMP-1 and -9 to their active forms, indicative of collagen degradation. Cilomilast inhibited the release of MMP-1 and -9, as well as conversion of MMP-1 to its active form. Using real-time PCR analysis, cilomilast's effect on MMP-1 release was not associated with the proteinase's mRNA expression, suggesting that the inhibition of release is regulated at the post-transcriptional level. These results suggest that cilomilast may be a potentially effective therapeutic agent in diseases characterized by excessive tissue destruction, such as emphysema.
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PMID:Phosphodiesterase 4 inhibitor cilomilast inhibits fibroblast-mediated collagen gel degradation induced by tumor necrosis factor-alpha and neutrophil elastase. 1235 83


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