Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034069 (pulmonary fibrosis)
 7,050 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of tobacco smoking in the development and outcome of pulmonary fibrosis is uncertain. To approach the effects of cigarette smoke on bleomycin-induced lung fibrosis, we studied five groups of guinea pigs: 1) controls, 2) instilled with bleomycin (B), 3) exposed to tobacco smoke for 6 wk (TS), 4) bleomycin instillation plus tobacco smoke exposure for 6 wk (B+TS), and 5) tobacco smoke exposure for 6 wk and bleomycin after smoking (TS/B). Guinea pigs receiving bleomycin and tobacco smoke exposure exhibited higher fibrotic lesions including a significant increase in the number of positive alpha-smooth muscle actin cells compared with bleomycin alone (B+TS, 3.4 +/- 1.2%; TS/B, 3.7 +/- 1.5%; B, 2.3 +/- 1.5%; P < 0.01). However, only the TS/B group reached a significant increase in lung collagen compared with the bleomycin group (TS/B, 3.5 +/- 0.7; B +/- TS, 2.9 +/- 0.4; B, 2.4 +/- 0.2 mg hydroxyproline/lung; P < 0.01). Bronchoalveolar lavage (BAL) from TS/B showed an increased number of eosinophils and higher levels of IL-4 and tissue inhibitor of metalloproteinase-2 (P < 0.01 for all comparisons) and induced a significant increase in fibroblast proliferation (P < 0.05). Importantly, smoke exposure alone induced an increase in BAL neutrophils, matrix metalloproteinase-9, and fibroblast proliferation compared with controls, suggesting that tobacco smoke creates a profibrotic milieu that may contribute to the increased bleomycin-induced fibrosis.
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PMID:Cigarette smoke exposure potentiates bleomycin-induced lung fibrosis in guinea pigs. 1284 6

Chronic hypoxia is implicated in lung fibrosis, which is characterized by enhanced deposition of extracellular matrix (ECM) molecules. Transforming growth factor-beta (TGF-beta) plays a key role in fibroblast homeostasis and is involved in disease states characterized by excessive fibrosis, such as pulmonary fibrosis. In this study, we investigated if hypoxia modulates the effects of TGF-beta on the expression of gelatinases: matrix metalloproteinase (MMP)-2 and MMP-9, interstitial collagenases: MMP-1 and MMP-13, tissue inhibitors of MMP (TIMP), collagen type I and interleukin-6 (IL-6). Primary human lung fibroblasts, established from tissue biopsies, were cultivated under normoxia or hypoxia in the presence of TGF-beta1, TGF-beta2 or TGF-beta3. Gelatinases were assessed by gelatin zymography and collagenases, TIMP, collagen type I and IL-6 by ELISA. Under normoxia fibroblasts secreted MMP-2, collagenases, TIMP, collagen type I and IL-6. TGF-betas significantly decreased MMP-1 and increased TIMP-1, IL-6 and collagen type I. Hypoxia significantly enhanced MMP-2, and collagenases. Compared to normoxia, the combination of TGF-beta and hypoxia reduced MMP-1, and further amplified the level of TIMP, IL-6, and collagen type I. Thus, in human lung fibroblasts hypoxia significantly increases the TGF-betas-induced secretion of collagen type I and may be associated to the accumulation of ECM observed in lung fibrosis.
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PMID:Hypoxia modulates the effects of transforming growth factor-beta isoforms on matrix-formation by primary human lung fibroblasts. 1456 88

Macrophage infiltration is implicated in various types of pulmonary fibrosis. One important pathogenetic process associated with pulmonary fibrosis is injury to basement membranes by matrix metalloproteinases (MMPs) that are produced mainly by macrophages. In this study, C-C chemokine receptor 2-deficient (CCR2-/-) mice were used to explore the relationship between macrophage infiltration and MMP activity in the pathogenesis of pulmonary fibrosis, using the bleomycin-induced model of this disease process. CCR2 is the main (if not only) receptor for monocyte chemoattractant protein-1/C-C chemokine ligand 2 (MCP-1/CCL2), which is a critical mediator of macrophage trafficking, and CCR2 -/- mice demonstrate defective macrophage migration. Pulmonary fibrosis was induced in CCR2-/- and wild-type (CCR2+/+) mice by intratracheal instillation of bleomycin. No significant differences in the total protein concentration in bronchoalveolar lavage (BAL) fluid, or in the degree of histological lung inflammation, were observed in the two groups until day 7. Between days 3 and 21, however, BAL fluid from CCR2-/- mice contained fewer macrophages than BAL fluid from CCR2+/+ mice. Gelatin zymography of BAL fluid and in situ zymography revealed reduced gelatinolytic activity in CCR2-/- mice. Immunocytochemical staining showed weaker expression of MMP-2 and MMP-9 in macrophages in BAL fluid from CCR2-/- mice at day 3. Gelatin zymography of protein extracted from alveolar macrophages showed reduced gelatinolytic activity of MMP-2 and MMP-9 in CCR2-/- mice. At days 14 and 21, lung remodelling and the hydroxyproline content of lung tissues were significantly reduced in CCR2-/- mice. These results suggest that the CCL2/CCR2 functional pathway is involved in the pathogenesis of bleomycin-induced pulmonary fibrosis and that CCR2 deficiency may improve the outcome of this disease by regulating macrophage infiltration and macrophage-derived MMP-2 and MMP-9 production.
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PMID:C-C chemokine receptor 2 (CCR2) deficiency improves bleomycin-induced pulmonary fibrosis by attenuation of both macrophage infiltration and production of macrophage-derived matrix metalloproteinases. 1553 37

Idiopathic pulmonary fibrosis (IPF) is a progressive, fibrotic lung disease of unknown etiology. A viral pathogenesis in IPF has been suggested since >95% of IPF patients have evidence of chronic pulmonary infection with one or more herpesviruses. To determine whether pulmonary infection with herpesvirus can cause lung fibrosis, we infected mice with the murine gamma-herpesvirus 68 (MHV68). Because IPF patients have a T helper type 2 (Th2) pulmonary phenotype, we used IFN-gammaR-/-, a strain of mice biased to develop Th2 responses. Chronic MHV68 infection of IFN-gammaR-/- mice resulted in progressive deposition of interstitial collagen as shown by light and electron microscopy. A significant decrease in tidal volume paralleled the collagen deposition. Five features typically seen in IPF, increased transforming growth factor-beta expression, myofibroblast transformation, production of Th2 cytokines, hyperplasia of type II cells, and increased expression of matrix metalloproteinase-7, were also present in chronically infected IFN-gammaR-/- mice. There also was altered synthesis of surfactant proteins, which is seen in some patients with familial IPF. MHV68 viral protein was found in type II alveolar epithelial cells, especially in lung areas with extensive alveolar remodeling. In summary, chronic herpesvirus pulmonary infection in IFN-gammaR-/- mice causes progressive pulmonary fibrosis and many of the pathological features seen in IPF.
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PMID:Lung infection with gamma-herpesvirus induces progressive pulmonary fibrosis in Th2-biased mice. 1573 89

We assessed the effects of long-term inhalation of toner on the pathological changes and gene expression with the synthesis and degradation of collagenous extracellular matrix in a rat model. Female Wistar rats (10 wk old) were divided evenly into a high concentration exposure group (H: 15.2 mg/m3), a low concentration exposure group (L: 5.5 mg/m3), and a control group. The mass median aerodynamic diameter of toner was 4.5 microm. The rats were sacrificed at the termination of a 1-yr or 2-yr inhalation period. Pathological examination was performed from the left lung, and transcriptional levels of mRNA extracted from the right lung were assessed by semiquantitative reverse-transcription polymerase chain polymerase (RT-PCR). The pathological findings showed mild pulmonary fibrosis in 20% (L, 1 yr), 40% (H, 1 yr), 56% (L, 2 yr) and 62% (H, 2 yr), while lung cancer was not observed in any of the exposed groups. In the 1-yr high-concentration group, gene expression of matrix metalloproteinase-2 (MMP-2) and type I collagen mRNA in the rat lungs increased, while tissue inhibitors of metalloproteinase-2 (TIMP-2) decreased. The 2-yr high-concentration group increased in message level of type I collagen and TIMP-2 but not that of MMP-2. These data suggested that results of gene expression of MMP, TIMP, and collagen in the 2-yr exposure may lead to accumulation of collagen compared to the 1-yr exposure, and that the imbalance of the expression of MMPs, TIMPs, and extracellular matrix might be associated with pulmonary fibrosis induced by toner.
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PMID:Effect of long-term inhalation of toner on extracellular matrix in the lungs of rats in vivo. 1578 76

Inhalation of asbestos fibers causes pulmonary inflammation and eventual pulmonary fibrosis (asbestosis). Although the underlying molecular events are poorly understood, protease/antiprotease and oxidant/antioxidant imbalances are believed to contribute to the disease. Implicated in other forms of pulmonary fibrosis, the matrix metalloproteinases (MMPs) have not been examined in asbestosis. We therefore hypothesized that MMPs play a pathogenic role in asbestosis development. Wild-type C57BL/6 mice were intratracheally instilled with 0.1 mg crocidolite asbestos, causing an inflammatory response at 1 d and a developing fibrotic response at 7, 14, and 28 d. Gelatin zymography demonstrated an increase in MMP-9 (gelatinase B) during the inflammatory phase, while MMP-2 (gelatinase A) was profoundly increased in the fibrotic phase. Immunohistochemistry revealed MMP-9 in and around bronchiolar and airspace neutrophils that were often associated with visible asbestos fibers. MMP-2 was found in fibrotic regions at 7, 14, and 28 d. No increases in RNA levels of MMP-2, MMP-9, or MMP-8 were found, but levels of MMP-7, MMP-12, and MMP-13 RNA did increase at 14 d. The MMP inhibitors, TIMP-1 and TIMP-2, were also increased at 7-28 d after asbestos exposure. To confirm the importance of MMP activity in disease progression, mice exposed to asbestos were given daily injections of the MMP inhibitor, GM6001. MMP inhibition reduced inflammation and fibrosis in asbestos-treated mice. Collectively, these data suggest that MMPs contribute to the pathogenesis of asbestosis through effects on inflammation and fibrosis development.
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PMID:Matrix metalloproteinases promote inflammation and fibrosis in asbestos-induced lung injury in mice. 1657 44

The peptide hormone relaxin is a known modulator of connective tissue and the extracellular matrix by virtue of its ability to regulate matrix metalloproteinases (MMPs). Relaxin knockout mice exhibit age-related pulmonary fibrosis, and delivery of recombinant human H2 relaxin ameliorates fibrotic-like conditions in the mouse lung. We investigated whether lentiviral vectors (LVs) engineering the expression of murine relaxins could induce MMP activity in the mouse lung. Mouse relaxin and mouse relaxin-3 peptides engineered by recombinant LVs were biologically active as shown by stimulation of cAMP from both THP-1 and 293T cells stably expressing relaxin receptor LGR7 and by up-regulation of MMP-2 activity from primary C57BL/6 lung cell cultures. To provide the virions with enhanced tropism for the lung, LVs were pseudotyped with the Zaire strain of the Ebola virus glycoprotein (EboZ GP) and delivered by endotracheal intubation. LVs engineering luciferase pseudotyped with EboZ GP, but not with vesicular stomatitis virus glycoprotein resulted in successful LV transduction and transgene expression in C57BL/6 mouse lung by as early as d 4. Mice treated via tracheal delivery with EboZ GP pseudotyped LVs that engineered expression of mouse relaxins exhibited increased MMP-2 and MMP-9 activity in lung tissue up until the end of our study at d 21. Taken together, this study provides proof-of- principle that relaxin gene expression targeted to the mouse lungs can result in enhanced MMP activity offering potential for alleviating disease conditions characterized by dysregulation of extracellular matrix protein accumulation.
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PMID:Functional expression of mouse relaxin and mouse relaxin-3 in the lung from an Ebola virus glycoprotein-pseudotyped lentivirus via tracheal delivery. 1670 14

Fibrosis, apoptosis, and the exaggerated production of transforming growth factor (TGF)-beta(1) are juxtaposed in a variety of pulmonary diseases including the interstitial lung diseases and asthma. In these disorders, the relationships between these responses are not well defined. In addition, the apoptosis pathways that contribute to these responses and the mechanism(s) of their contribution have not been described. We hypothesized that BH3 domain-only protein-induced apoptosis plays an important role in the pathogenesis of TGF-beta(1)-induced pulmonary responses. To test this hypothesis, we characterized the effects of transgenic TGF-beta(1) in mice with wild type (WT) and null Bax loci. To investigate the mechanisms of Bax activation and its effector functions, we also compared the effects of TGF-beta(1) in mice with WT and null Bid and matrix metalloproteinase (MMP)-12 loci, respectively. These studies demonstrate that TGF-beta(1) is a potent stimulator of Bax, Bid, and MMP-12. The studies also demonstrate that Bax and Bid play key roles in the pathogenesis of TGF-beta(1)-induced inflammation, fibrosis, and apoptosis; that TGF-beta(1) stimulates MMP-12, TIMP-1, and cathepsins and inhibits MMP-9 and p21 via Bax- and Bid-dependent mechanisms; and that TGF-beta(1)-stimulated pulmonary fibrosis is ameliorated in MMP-12-deficient animals. Finally, they demonstrate that Bax, Bid, and MMP-12 play similar roles in bleomycin-induced fibrosis, thereby highlighting the importance of this Bid-activated, Bax-mediated pathway and downstream MMP-12 in a variety of fibrogenic settings.
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PMID:Transforming growth factor (TGF)-beta1 stimulates pulmonary fibrosis and inflammation via a Bax-dependent, bid-activated pathway that involves matrix metalloproteinase-12. 1720 37

Elevated pulmonary levels of CCL18 have been associated with influx of T lymphocytes, collagen accumulation, and a decline in lung function in pulmonary fibrosis patients. We previously reported that overexpression of CCL18 in mouse lungs triggers selective infiltration of T lymphocytes and moderate lymphocyte-dependent collagen accumulation. We hypothesized that in combination with bleomycin injury, overexpression of CCL18 will worsen the severity of lung inflammation and fibrosis. Mice were infected with a replication-deficient adenovirus encoding CCL18 and then instilled with bleomycin; control mice were challenged with either CCL18 overexpression or bleomycin. Additive effects of CCL18 overexpression and bleomycin injury were observed on pulmonary inflammation, particularly on T-cell infiltration, and increased levels of tumor necrosis factor-alpha, interferon-gamma, matrix metalloproteinase (MMP)-2, and MMP-9. Despite the additive effect on inflammation, CCL18 overexpression unexpectedly attenuated the bleomycin-induced collagen accumulation. Pulmonary levels of active transforming growth factor-beta1 mirrored the changes in collagen levels. Depletion of T cells with antilymphocyte serum or pharmacological inhibition of MMPs with GM6001 abrogated accumulation of collagen and increases in the levels of tumor necrosis factor-alpha, interferon-gamma, and active transforming growth factor-beta1. Thus, CCL18-stimulated T-lymphocytic infiltration is by itself mildly profibrotic to a healthy lung, whereas it partially protects against lung fibrosis in an inflammatory profibrotic pulmonary milieu.
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PMID:Complex regulation of pulmonary inflammation and fibrosis by CCL18. 1756 79

Idiopathic pulmonary fibrosis has been associated with emphysema in cigarette smokers as a new clinical entity: combined pulmonary fibrosis and emphysema (CPFE). In order to compare histomorphometrical, roentgenological and immunohistochemical aspects of usual interstitial pneumonia (UIP) with and without associated pulmonary emphysema, 17 patients with biopsy-proven UIP were evaluated. Morphometrical evaluation of lung parenchyma destruction was used to divide patients in two subgroups: emphysema/UIP (n=9) and UIP alone (n=8); four patients with biopsy-proven emphysema without fibrosis were also evaluated. At HRTC scan, emphysematous lesions were prevalent in the upper fields of both emphysema/UIP and emphysema groups and the distribution of fibrotic lesions was similar in emphysema/UIP compared to UIP alone. The semiquantitative histopathological fibrotic score was also similar in emphysema/UIP and UIP alone. In addition, the expression of tumor necrosis factor (TNF)-alpha, matrix metalloproteinase (MMP)-2, MMP-9, MMP-7 and membrane type 1-metalloproteinase (MT1-MMP) by fibroblasts of myofibroblastic foci was similar in emphysema/UIP and UIP alone patients. In contrast, fibroblasts in areas of parenchymal destruction of emphysema/UIP expressed MMP-2, MMP-9, MMP-7 and MT1-MMP at variable but significantly higher levels when compared to emphysema subjects, in the presence of similar levels of TIMP-1, TIMP-2 and TNF-alpha. Fibrotic and emphysematous lesions in emphysema/UIP patients appear to follow the roentgenological and histopathological patterns expected for either UIP or emphysema. Interstitial fibroblast activation is more pronounced in the areas of lung destruction in emphysema/UIP compared to those with emphysema alone, as for exaggerated tissue remodeling.
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PMID:HRCT and histopathological evaluation of fibrosis and tissue destruction in IPF associated with pulmonary emphysema. 1872 34


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