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)

Semaphorin (SEMA) 7A regulates neuronal and immune function. In these studies, we tested the hypothesis that SEMA 7A is also a critical regulator of tissue remodeling. These studies demonstrate that SEMA 7A and its receptors, plexin C1 and beta1 integrins, are stimulated by transforming growth factor (TGF)-beta(1) in the murine lung. They also demonstrate that SEMA 7A plays a critical role in TGF-beta(1)-induced fibrosis, myofibroblast hyperplasia, alveolar remodeling, and apoptosis. TGF-beta(1) stimulated SEMA 7A via a largely Smad 3-independent mechanism and stimulated SEMA 7A receptors, matrix proteins, CCN proteins, fibroblast growth factor 2, interleukin 13 receptor components, proteases, antiprotease, and apoptosis regulators via Smad 2/3-independent and SEMA 7A-dependent mechanisms. SEMA 7A also played an important role in the pathogenesis of bleomycin-induced pulmonary fibrosis. TGF-beta(1) and bleomycin also activated phosphatidylinositol 3-kinase (PI3K) and protein kinase B (PKB)/AKT via SEMA 7A-dependent mechanisms, and PKB/AKT inhibition diminished TGF-beta(1)-induced fibrosis. These observations demonstrate that SEMA 7A and its receptors are induced by TGF-beta(1) and that SEMA 7A plays a central role in a PI3K/PKB/AKT-dependent pathway that contributes to TGF-beta(1)-induced fibrosis and remodeling. They also demonstrate that the effects of SEMA 7A are not specific for transgenic TGF-beta(1), highlighting the importance of these findings for other fibrotic stimuli.
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PMID:Semaphorin 7A plays a critical role in TGF-beta1-induced pulmonary fibrosis. 1748 10

Pulmonary fibrosis in humans can occur as a result of a large number of conditions. In idiopathic pulmonary fibrosis (IPF), pulmonary function becomes progressively compromised resulting in a high mortality rate. Currently there are no proven effective treatments for IPF. We have recently reported that IL-6 and TGF-beta(1) plays an important role in proliferation and differentiation of lung fibroblasts, and all-trans-retinoic acid (ATRA) prevented bleomycin-induced lung fibrosis through the inhibition of these cytokines. Thalidomide (Thal) has been used in the treatment of multiple myeloma through the inhibitory effect on IL-6-dependent cell growth and angiogenesis. In this study, we examined the preventive effect of Thal on bleomycin-induced pulmonary fibrosis in mice. We performed histological examinations and quantitative measurements of IL-6, TGF-beta(1), collagen type Ialpha1 (COL1A1), vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) in bleomycin-treated mouse lung tissues with or without the administration of Thal. Thal histologically ameliorated bleomycin-induced fibrosis in mouse lung tissues. Thal decreased the expressions of IL-6, TGF-beta(1), VEGF, Ang-1 Ang-2, and COL1A1 mRNA in mouse lung tissues. In addition, Thal inhibited angiogenesis in the lung. In vitro studies disclosed that Thal reduced 1) production of IL-6, TGF-beta(1), VEGF, Ang-1, and collagen synthesis from human lung fibroblasts, and 2) both IL-6-dependent proliferation and TGF-beta(1)-dependent transdifferentiation of the cells, which could be the mechanism underlying the preventive effect of Thal on pulmonary fibrosis. These data may provide a rationale to explore clinical use of Thal for the prevention of pulmonary fibrosis.
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PMID:Thalidomide prevents bleomycin-induced pulmonary fibrosis in mice. 1757 94

Pulmonary fibrosis is a group of disorders characterized by accumulation of scar tissue in the lung interstitium, resulting in loss of alveolar function, destruction of normal lung architecture, and respiratory distress. Some types of fibrosis respond to corticosteroids, but for many there are no effective treatments. Prognosis varies but can be poor. For example, patients with idiopathic pulmonary fibrosis (IPF) have a median survival of only 2.9 years. Prognosis may be better in patients with some other types of pulmonary fibrosis, and there is variability in survival even among individuals with biopsy-proven IPF. Evidence is accumulating that the peroxisome proliferator-activated receptors (PPARs) play important roles in regulating processes related to fibrogenesis, including cellular differentiation, inflammation, and wound healing. PPARalpha agonists, including the hypolidipemic fibrate drugs, inhibit the production of collagen by hepatic stellate cells and inhibit liver, kidney, and cardiac fibrosis in animal models. In the mouse model of lung fibrosis induced by bleomycin, a PPARalpha agonist significantly inhibited the fibrotic response, while PPARalpha knockout mice developed more serious fibrosis. PPARbeta/delta appears to play a critical role in regulating the transition from inflammation to wound healing. PPARbeta/delta agonists inhibit lung fibroblast proliferation and enhance the antifibrotic properties of PPARgamma agonists. PPARgamma ligands oppose the profibrotic effect of TGF-beta, which induces differentiation of fibroblasts to myofibroblasts, a critical effector cell in fibrosis. PPARgamma ligands, including the thiazolidinedione class of antidiabetic drugs, effectively inhibit lung fibrosis in vitro and in animal models. The clinical availability of potent and selective PPARalpha and PPARgamma agonists should facilitate rapid development of successful treatment strategies based on current and ongoing research.
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PMID:The Role of PPARs in Lung Fibrosis. 1771 Feb 35

The pathogenesis of pulmonary fibrosis remains unclear. The receptor for advanced glycation end-products (RAGE) is a multi-ligand receptor known to be involved in the process of fibrotic change in several organs, such as peritoneal fibrosis and kidney fibrosis. The aim of this study was to examine the contribution of RAGE during the acute inflammation and chronic fibrotic phases of lung injury induced by intratracheal instillation of bleomycin in mice. Bleomycin-induced lung fibrosis was evaluated in wild-type and RAGE-deficient (RAGE-/-) mice. Bleomycin administration to wild-type mice caused an initial pneumonitis that evolved into fibrosis. While RAGE-/- mice developed a similar early inflammatory response, the mice were largely protected from the late fibrotic effects of bleomycin. The protection afforded by RAGE deficiency was accompanied by reduced pulmonary levels of the potent RAGE-inducible profibrotic cytokines transforming growth factor (TGF)-beta and PDGF. In addition, bleomycin administration induced high mobility group box 1 (HMGB-1) production, one of the ligands of RAGE, from inflammatory cells that accumulated within the air space. Coculture with HMGB-1 induced epithelial-mesenchymal transition (EMT) in alveolar type II epithelial cells from wild-type mice. However, alveolar type II epithelial cells derived from RAGE-/- mice did not respond to HMGB-1 treatment, such that the RAGE/HMGB-1 axis may play an important role in EMT. Also, bleomycin administration induced profibrotic cytokines TGF-beta and PDGF only in wild-type mouse lungs. Our results suggested that RAGE contributes to bleomycin-induced lung fibrosis through EMT and profibrotic cytokine production. Thus, RAGE may be a new therapeutic target for pulmonary fibrosis.
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PMID:The role of the receptor for advanced glycation end-products in lung fibrosis. 1795 14

Pulmonary fibrosis is characterized by the accumulation of fibroblasts, myofibroblasts, collagen, and other extracellular matrix proteins in the interstitium of the lung, with subsequent scarring and destruction of the alveolar capillary interface. In some cases, pulmonary fibrosis is preceded by lung inflammation and can be treated with anti-inflammatory therapies. However, idiopathic pulmonary fibrosis is characterized by a relative paucity of underlying inflammation and currently has no effective treatment. There is increasing evidence that the transcription factor peroxisome proliferator-activated receptor (PPAR) gamma plays an important role in controlling cell differentiation and that PPARgamma ligands can modify inflammatory and fibrotic responses. Peroxisome proliferator-activated receptor gamma ligands, including the thiazolidinedione class of antidiabetic drugs and novel triterpenoid compounds derived from oleanic acid, inhibit TGF-beta-stimulated profibrotic differentiation of lung fibroblasts in vitro and reduce lung scarring in animal models of fibrosis. The mechanism of action of the PPARgamma ligands is under investigation but seems to involve both PPARgamma-dependent and PPARgamma-independent pathways. These in vitro and in vivo data highlight the potentially exciting role of PPARgamma ligands as novel therapies for fibrosis of the lung and other organ systems prone to scarring. Many of the synthetic PPARgamma ligands are orally active, and several are currently available and Food Drug Administration approved for use in therapy of type 2 diabetes. Further research is urgently required to more clearly elucidate the mechanism of action of these drugs and to develop more potent antifibrotic agents for patients with scarring diseases for whom there are currently few effective therapies.
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PMID:The antifibrogenic potential of PPARgamma ligands in pulmonary fibrosis. 1831 37

One of the hallmarks of idiopathic pulmonary fibrosis with a usual interstitial pneumonia histological pathology (IPF/UIP) is excess collagen deposition, due to enhanced fibroblast extracellular matrix synthetic activity. Studies using murine models of lung fibrosis have elucidated a pro-fibrotic pathway involving IL-13 driving CCL2, which in turn drives TGFbeta1 in lung fibroblasts. Therefore, we sought to determine whether this pathway exists in the human fibrotic setting by evaluating human IPF/UIP fibroblasts. IPF/UIP fibroblasts have an increased baseline fibrotic phenotype compared to non-fibrotic fibroblasts. Interestingly, non-fibrotic fibroblasts responded in a pro-fibrotic manner to TGFbeta1 but were relatively non-responsive to IL-13 or CCL2, whereas, IPF/UIP cells were hyper-responsive to TGFbeta1, IL-13 and CCL2. Interestingly, TGFbeta1, CCL2 and IL-13 all upregulated TGFbeta receptor and IL-13 receptor expression, suggesting an ability of the mediators to modulate the function of each other. Furthermore, in vivo, neutralization of both JE and MCP5, the two functional orthologs of CCL2, during bleomycin-induced pulmonary fibrosis significantly reduced collagen deposition as well as JE and CCR2 expression. Also in the bleomycin model, CTGF, which is highly induced following TGFbeta stimulation, was attenuated with anti-JE/anti-MCP5 treatment. Overall this study demonstrates an interplay between TGFbeta1, IL-13 and CCL2 in IPF/UIP, where these three mediators feedback on each other, promoting the fibrotic response.
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PMID:Hyper-responsiveness of IPF/UIP fibroblasts: interplay between TGFbeta1, IL-13 and CCL2. 1839 86

Tumor necrosis factor-alpha (TNFalpha) and transforming growth factor-beta(1) (TGFbeta(1)) are potent peptide growth factors that are likely to play important roles in the development of interstitial pulmonary fibrosis (IPF). Previously we showed that TNFalpha and TGFbeta(1) are up-regulated in macrophages, epithelial and mesenchymal cells early after exposure to chrysotile asbestos, particularly at sites of fiber deposition in vivo. We also showed that TNFalpha receptor knockout mice are resistant to asbestos-induced fibrosis. Importantly, vectors that over-express TNFalpha cause inflammation and fibrogenesis along with increased TGFbeta(1) production in C57Bl/6 mice. Recently we reported that TNFalpha activates the extracellular regulated kinase pathway in fibroblasts leading to a 200-400% increase in TGFbeta(1) mRNA and protein. The mechanism of TNFalpha induction of TGFbeta(1) expression appears to be complex, involving both transcriptional and post-transcriptional mechanisms. In asbestos-exposed animals, this TGFbeta(1) is produced on alveolar surfaces in a latent form (controlled by binding of a latent associated peptide [LAP]) that must be activated for the TGFbeta(1) to bind to its receptors and induce its multiple biological effects. Thus, we recently reported that, in vitro, reactive oxygen species (ROS) derived from chrysotile and crocidolite asbestos activate TGFbeta(1) by oxidation of the LAP. Now, in preliminary findings, we have shown that over-expression of latent TGFbeta(1) prior to asbestos exposure of fibrogenic-resistant TNFalpha receptor knockout mice produces asbestos lesions with the same severity as seen in normal C57/Bl6 mice. This finding plus the demonstration of increased amounts of TGFbeta(1), increased Smad activation and amelioration of the developing disease by treating the mice with an anti-oxidant all support the concept that, in vivo, latent TGFbeta(1) is activated by asbestos-generated oxygen radicals and consequently mediates at least a component of the consequent fibrogenesis. Taken together, these findings support the postulate that TNFalpha controls fibrogenesis by regulating TGFbeta(1) expression and that one mechanism through which ROS induce lung fibrosis is by activating latent TGFbeta(1).
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PMID:The latent form of TGFbeta(1) is induced by TNFalpha through an ERK specific pathway and is activated by asbestos-derived reactive oxygen species in vitro and in vivo. 1856 84

It has been demonstrated that alveolar macrophages (AMs) play a key role in the pathogenesis of pulmonary fibrosis by releasing a variety of cytokines and inflammatory mediators. In addition, abnormal signal transducer and activator of transcription-1 (STAT1) activation in AMs may play a pivotal role in the process of alveolitis and pulmonary fibrosis. In this study, we transfected STAT1 antisense oligodeoxynucleotide (ASON) into rats by aerosolization, and then investigated the effect of STAT1 ASON on inflammatory mediators such as TGF-beta, PDGF and TNF-alpha in bronchoalveolar lavage fluid (BALF) from rats with bleomycin (BLM)-induced rat pulmonary fibrosis. Our results showed that STAT1 ASON by aerosolization could enter into lung tissues and AMs. STAT1 ASON could inhibit mRNA and protein expressions of STAT1 and ICAM-1 in AMs of rat with pulmonary fibrosis, and had no toxic side effect on liver and kidney. Aerosolized STAT1 ASON could ameliorate the alveolitis through inhibiting the secretion of inflammatory mediators in BLM-induced rat pulmonary fibrosis. These results suggest that aerosolized STAT1 ASON might be considered as a promising new strategy in the treatment of pulmonary fibrosis.
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PMID:Aerosolized STAT1 antisense oligodeoxynucleotides decrease the concentrations of inflammatory mediators in bronchoalveolar lavage fluid in bleomycin-induced rat pulmonary fibrosis. 1858 4

Scleroderma-associated interstitial lung disease (SSc-ILD) occurs frequently and for many patients SSc-ILD is a significant complication of their disease. SSc-ILD is now one of the leading causes of death among patients with SSc. SSc-ILD, classified most often as a non-specific interstitial pneumonia, may culminate in interstitial pulmonary fibrosis and end-stage lung disease. Fibrosis in the lung is the net result of fibroblast proliferation and deposition of excessive amounts of extracellular matrix proteins. Among the many cytokines and growth factors involved in the pathogenesis of SSc-ILD, ET-1 may be a central mediator. In vitro and in vivo studies of animals and SSc patients support the notion that ET-1 can enhance the proliferation of pulmonary mesenchymal cells and may also enhance the fibrogenic effects of TGF-beta. Two well-designed randomized controlled trials of the dual ET receptor blocker bosentan were negative in their primary (and for SSc also secondary) endpoints, although there might be explanations for this apparent lack of efficacy.
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PMID:Endothelin and scleroderma lung disease. 1878 34

Pulmonary fibrosis is characterized by chronic inflammation and excessive collagen deposition. Neutrophils are thought to be involved in the pathogenesis of lung fibrosis. We hypothesized that CXCR2-mediated neutrophil recruitment is essential for the cascade of events leading to bleomycin-induced pulmonary fibrosis. CXCL1/KC was detected as early as 6 hours after bleomycin instillation and returned to basal levels after Day 8. Neutrophils were detected in bronchoalveolar lavage and interstitium from 12 hours and peaked at Day 8 after instillation. Treatment with the CXCR2 receptor antagonist, DF2162, reduced airway neutrophil transmigration but led to an increase of neutrophils in lung parenchyma. There was a significant reduction in IL-13, IL-10, CCL5/RANTES, and active transforming growth factor (TGF)-beta(1) levels, but not on IFN-gamma and total TGF-beta(1,) and enhanced granulocyte macrophage-colony-stimulating factor production in DF2162-treated animals. Notably, treatment with the CXCR2 antagonist led to an improvement of the lung pathology and reduced collagen deposition. Using a therapeutic schedule, DF2162 administered from Days 8 to 16 after bleomycin reduced pulmonary fibrosis and levels of active TGF-beta(1) and IL-13. DF2162 treatment reduced bleomycin-induced expression of von Willebrand Factor, a marker of angiogenesis, in the lung. In vitro, DF2162 reduced the angiogenic activity of IL-8 on human umbilical vein endothelial cells. In conclusion, we show that CXCR2 plays an important role in mediating fibrosis after bleomycin instillation. The compound blocks angiogenesis and the production of pro-angiogenic cytokines, and decreases IL-8-induced endothelial cell activation. An effect on neutrophils does not appear to account for the major effects of the blockade of CXCR2 in the system.
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PMID:Role of the chemokine receptor CXCR2 in bleomycin-induced pulmonary inflammation and fibrosis. 1883 37


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