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)

Fibrosis, characterized by the accumulation of collagen, is a late result of thoracic irradiation. The purpose of this study was to determine if extracellular matrix protein and transforming growth factor beta mRNA expression are altered late in the course of pulmonary fibrosis after irradiation, and then to determine if these changes differ between two strains of mice which vary in their sensitivity to radiation. Radiation-sensitive (C57BL/6) and radiation-resistant (C3H/HeJ) mice were irradiated with a single dose of 5 or 12.5 Gy to the thorax. Total lung RNA was prepared and immobilized by Northern and slot blotting and hybridized with radiolabeled cDNA probes for collagens I, III and IV, fibronectin, and transforming growth factor beta 1 and beta 3. Autoradiographic data were quantified by video densitometry and results normalized to a control probe encoding for glyceraldehyde-3-phosphate dehydrogenase. Alterations in mRNA abundance were observed in the sensitive mice at all times, while levels in the resistant mice were unaffected until 26 weeks after irradiation. The relationship between extracellular matrix protein per se and increased mRNA abundance suggests that late matrix protein accumulation may be a function of gene expression. Differences in levels of transforming growth factor beta mRNA may lead to strain-dependent variation in fibrotic response and may also contribute to the radiation-induced component of pulmonary fibrosis.
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PMID:Differences in correlation of mRNA gene expression in mice sensitive and resistant to radiation-induced pulmonary fibrosis. 772 35

Sarcoidosis is a chronic inflammatory disease of unknown cause characterized by the formation of nonnecrotizing granulomas in affected tissues, most notably the lungs. Granuloma healing may result in pulmonary fibrosis and respiratory impairment in some patients. Transforming growth factor-beta 1 (TGF-beta 1) is a potent cytokine that promotes fibrosis by enhancing the synthesis of extracellular matrix components, including fibronectin and the alpha 5 beta 1 fibronectin receptor. The role of TGF-beta 1 in promoting lung fibrosis in the setting of pulmonary sarcoidosis has not yet been investigated. Accordingly, we determined the extent and distribution of TGF-beta 1 in lung tissue obtained from seven patients with clinical and histologic features of pulmonary sarcoidosis. The tissue distributions of TGF-beta 1, the TGF-beta 1 binding proteoglycan decorin, fibronectin, and the alpha 5 beta 1 fibronectin receptor were assessed immunohistochemically. In all cases, the epithelioid histiocytes comprising nonnecrotizing granulomas of pulmonary sarcoidosis contained abundant TGF-beta 1. We further demonstrated decorin, fibronectin, and the alpha 5 beta 1 fibronectin receptor within nonnecrotizing granulomas and in the fibrous tissue surrounding the lesions. TGF-beta 1 staining was also observed in bronchiolar epithelial cells, hyperplastic Type II pneumocytes, and occasional alveolar macrophages. This study demonstrates enhanced tissue localization of TGF-beta 1 and related extracellular matrix proteins associated with the nonnecrotizing granulomas of pulmonary sarcoidosis. Through its actions on matrix protein synthesis, TGF-beta 1 may modulate the fibrotic repair process accompanying granuloma healing in sarcoidosis.
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PMID:Immunohistochemical localization of transforming growth factor-beta 1 in the nonnecrotizing granulomas of pulmonary sarcoidosis. 811 83

Interstitial fibrosis is seen in the lung in response to a variety of insults, and often appears stereotypical in terms of its clinical and pathological features. However, exposure to a known aetiological factor does not always lead to fibrosis. For example in bleomycin-induced pulmonary fibrosis, a wide variation in response is seen both in humans and in animal models, which is not completely accounted for by known risk factors. These observations and the existence of a number of familial forms of lung fibrosis suggest a genetic predisposition. Current hypotheses concerning the pathogenesis of pulmonary fibrosis propose an initial stage involving the influx of inflammatory cells into the interstitium. These cells, together with activated resident cells are then thought to release polypeptide mediators that stimulate the fibroblast proliferation and matrix protein synthesis typical of these disorders. Genetic influences could have an important role in regulating a number of these events, altering the immunological response to injury or modulating collagen metabolism in the lung. However, despite recent advances in molecular genetic techniques, there have been few human studies to date. Most have concentrated on genetic loci with a high degree of polymorphism such as the human leucocyte antigen (HLA) system and yield conflicting results. Others offer tantalising but as yet, incomplete insights into the mechanisms involved. Defining the genetic abnormalities underlying both the familial forms of pulmonary fibrosis and the variations seen in response to lung injury should enhance our understanding of the pathogenic processes and help to focus research in this area.
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PMID:The pathogenesis of pulmonary fibrosis: is there a fibrosis gene? 907 45

AFKBP65 (65-kDa FK506-binding protein) is an endoplasmic reticulum (ER)-localized peptidyl-prolyl cis-trans isomerase predicted to play a role in the folding and trafficking of secretory proteins. In previous studies, we have shown that FKBP65 is developmentally regulated and associates with the extracellular matrix protein, tropoelastin, during its maturation and transport through the ER. In this study, we show that FKBP65 is expressed in the lung with the same developmental pattern as tropoelastin and other matrix proteins. To test the hypothesis that FKBP65 is upregulated at times when extracellular matrix proteins are being actively synthesized and assembled, adult mice were treated with bleomycin to cause reinitiation of matrix protein production during the ensuing development of pulmonary fibrosis. After bleomycin instillation, FKBP65 expression was reactivated in the lung with a pattern similar to that observed for tropoelastin and type I collagen. Using human lung fibroblast cultures, we showed that FKBP65 does not undergo the unfolded protein response, a response associated with an upregulation of resident ER proteins that occurs after increased ER stress. When fibroblasts were treated with transforming growth factor (TGF)-beta1, which is upregulated during the development of pulmonary fibrosis and known to induce matrix production, FKBP65 expression and synthesis was also increased. Similar to type I collagen and tropoelastin, this response was completely inhibited in a dose-dependent manner by GGTI-298, a geranylgeranyl transferase I inhibitor. Treatment of fibroblasts with an inhibitor of ribonucleic acid (RNA) polymerase II after TGF-beta1 treatment showed that the effect of TGF-beta1 was not because of increased stabilization of the FKBP65 messenger RNA. In summary, we have shown that FKBP65 is highly expressed in lung development, downregulated in the adult, and can be reactivated in a coordinated manner with extracellular matrix proteins after lung injury. The expression pattern of FKBP65, which is atypical for general ER foldases, suggests that FKBP65 has a distinct set of developmentally regulated protein ligands. The response to injury, which may be in part a direct response to TGF-beta1, assures the presence of FKBP65 in the ER of cells actively producing components of the extracellular matrix.
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PMID:Developmental regulation and coordinate reexpression of FKBP65 with extracellular matrix proteins after lung injury suggest a specialized function for this endoplasmic reticulum immunophilin. 1633 83

Idiopathic pulmonary fibrosis (IPF) is a refractory and lethal interstitial lung disease characterized by alveolar epithelial cells apoptosis, fibroblast proliferation and extra-cellular matrix protein deposition. EBV, localised to alveolar epithelial cells of pulmonary fibrosis patients is associated with a poor prognosis. A strategy based on microarray-differential gene expression analysis to identify molecular drivers of EBV-associated lung fibrosis was utilized. Alveolar epithelial cells were infected with EBV to identify genes whose expression was altered following TGFbeta1-mediated lytic phase. EBV lytic reactivation by TGFbeta1 drives a selective alteration in CUX1 variant (a) (NCBI accession number NM_181552) expression, inducing activation of non-canonical Wnt pathway mediators, implicating it in Epithelial Mesenchymal Transition (EMT), the molecular event underpinning scar production in tissue fibrosis. The role of EBV in EMT can be attenuated by antiviral strategies and inhibition of Wnt signaling by using All-Trans Retinoic Acids (ATRA). Activation of non-canonical Wnt signaling pathway by EBV in epithelial cells suggests a novel mechanism of EMT via CUX1 signaling. These data present a framework for further description of the link between infectious agents and fibrosis, a significant disease burden.
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PMID:CUX1/Wnt signaling regulates epithelial mesenchymal transition in EBV infected epithelial cells. 1936 98

We have reported that von Hippel-Lindau protein (pVHL) expression is elevated in human and mouse fibrotic lungs and that overexpression of pVHL stimulates fibroblast proliferation. We sought to determine whether loss of pVHL in fibroblasts prevents injury and fibrosis in mice that are treated with bleomycin. We generated heterozygous fibroblast-specific pVHL (Fsp-VHL) knockdown mice (Fsp-VHL(+/-)) and homozygous Fsp-VHL knockout mice (Fsp-VHL(-/-)) by crossbreeding vhlh 2-lox mice (VHL(fl/fl)) with Fsp-Cre recombinase mice. Our data show that Fsp-VHL(-/-) mice, but not Fsp-VHL(+/-) mice, have elevated red blood cell counts, hematocrit, hemoglobin content, and expression of hypoxia-inducible factor (HIF) targets, indicating HIF activation. To examine the role of pVHL in bleomycin-induced lung injury and fibrosis in vivo, we administered PBS or bleomycin to age-, sex-, and strain-matched 8-week-old VHL(fl/fl), Fsp-VHL(+/-), and Fsp-VHL(-/-) mice. In Fsp-VHL(+/-) and Fsp-VHL(-/-) mice, bleomycin-induced collagen accumulation, fibroblast proliferation, differentiation, and matrix protein dysregulation were markedly attenuated. Suppression of pVHL also decreased bleomycin-induced Wnt signaling and prostaglandin E2 signaling but did not affect bleomycin-induced initial acute lung injury and lung inflammation. These results indicate that pVHL has a pivotal role in bleomycin-induced pulmonary fibrosis, possibly via an HIF-independent pathway. Paradoxically, pVHL does not affect bleomycin-induced lung injury and inflammation, indicating a separation of the mechanisms involved in injury/inflammation from those involved in pulmonary fibrosis.
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PMID:Suppression of von Hippel-Lindau Protein in Fibroblasts Protects against Bleomycin-Induced Pulmonary Fibrosis. 2648 90