Project description:We perfomed a microRNA microarray on to assess differentially expressed miRNAs in bleomycin-induced lung fibrosis in mice. To induce pulmonary fibrosis, belomycine (Sigma-Aldrich, St Louis, MO) was dissolved and administred intratracheally at a dose of 1.5U/kg body weight. Control animals received saline only. 21 days post bleomycin treatment, mice were sacrificed and lung tissue were collected for RNA extraction and microRNA microarray.
Project description:We conducted fibroblast-specific transcriptome analysis by next generation sequencing in order to investigate qualitative change and activation signatures of lung fibroblasts in bleomycin-induced pulmonary fibrosis. Lung fibroblasts were identified by using reporter mice of collagen-α2(I), in which collagen I-producing fibroblasts were labeled with EGFP. Lungs were dissociated with protease sollution, and single cell suspension were stained with lineage markers (Ter119, CD45, CD31, EpCAM). Lineage- GFP+ cells were sorted out and mRNA was collected. Using serial analysis of gene expression (SAGE) method, we identified 2,973,937 SAGE tags (1,080,798 tags from saline-treated GFP+ fibroblasts and 1,893,139 tags from bleomycin-treated GFP+ fibroblasts). We found that genes related to extracellular matrix construction were highly up-regulated in fibroblasts from belomycin-treated lungs. Moreover, an analysis of mRNA profiles revealed biological functions such as proliferation, invasion, adhesion, and migration were promoted in fibroblasts from bleomycin-treated lung, which recapitulated the role of fibroblasts in the fibrogenesis. These fibroblast-specific gene expression profiles will be important notions in future fibrosis studies. mRNA profiles of Lung fibroblasts from 3 mice at day 14 after saline or bleomycin treatment.
Project description:The molecular mechanisms of lung injury and fibrosis are incompletely understood. microRNAs (miRNAs) are crucial biological regulators by suppression of their target genes and are involved in a variety of pathophysiologic processes. To gain insight into miRNAs in the regulation of lung fibrosis, total RNA was isolated from lung samples harvested at different days after bleomycin treatment, and miRNA array was performed thereafter. miRNAs expressed in lungs with bleomycin treatment at different time points were compared to miRNAs expressed in lungs without bleomycin treatment, resulting in 161 miRNAs differentially expressed. Furthermore, miRNA expression patterns regulated in initial and late periods after bleomycin were identified. Target genes were predicted in silico for differentially expressed miRNAs, including miR-7f, miR-7g, miR-196b, miR-16, miR-195, miR-25, miR-144, miR-351, miR-34a, miR-499, miR-704, miR-717, miR-10a, miR-211, miR-34a, miR-367 and miR-21, and then cross-referenced to molecular pathways including apoptosis, Wnt, Toll-like receptor, and TGF-? signaling, which are involved in different pathological phenotypes such as apoptosis, inflammation, and fibrosis. Our study demonstrated relative abundance of miRNA levels in bleomycin-induced lung fibrosis. The miRNAs and their potential target genes identified herein contribute to the understanding of the complex transcriptional program of lung fibrosis. Under anesthesia, 2.5 U/kg bleomycin dissolved in sterile PBS was administered via trachea as previously described. Lung tissues were harvested at the time point of day 0, 3, 7, 14, and 21 post bleomycin challenges. 3 sample in specific time point, except for day 14 where nday14 = 2.
Project description:Background and objective: The role of bronchiolar epithelial cells in the pathogenesis of pulmonary fibrosis has not been addressed. We previously demonstrated that DNA damage was found in bronchiole at early phase, and subsequently extended to alveolar cells at later phase in bleomycin-induced pulmonary fibrosis in mice. Club cells are progenitor cells for bronchiole, and are recognized to play protective roles against lung inflammation and damage. The aim of the study was to elucidate the role of club cells in the development of pulmonary fibrosis. Methods: C57BL/6J mice were received naphthalene intraperitoneally at day -2 to deplete club cells, and were given intratracheal bleomycin or vehicle at day 0. Lung tissues were obtained at day 1, 7, and 14, and bronchoalveolar lavage was performed at day 14. Gene expression was analysed from bronchiolar ephithelial cells sampled by laser captured microdissection at day 14. Results: Surprisingly, naphthalene-induced club cell depletion protected mice from bleomycin-induced lung injury and fibrosis. We conclude that club cells are involved in the development of lung injury and fibrosis.
Project description:Pulmonary fibrosis is a disease characterized by inflammatory cell infiltration, scar formation, deposition of extracellular matrix, alveolar epithelial cell injury and hyperplasia. To determine if alterations in microRNA expression contribute to these phenotypes, microRNA expression profiling of the lungs from bleomycin treated C57Bl/6J mice, relative to that of untreated controls, was undertaken. Mice were treated at 8 weeks old with 100 Units/kg of bleomycin delivered subcutaneously with osmotic minipumps. At 42 days post treatment mice were euthanized and lung microRNA isolated. We identified 11 microRNA's to be significantly differentially expressed (FDR threshold of 0.01) in the lungs of bleomycin treated mice and confirmed these data with real time PCR measurements. These included bleomycin upregulated miR-34a, 335-5p, 207, 21, 301a, 146b, 199a-5p, and 449a and bleomycin downregulated miR-151-3p, 26a and 676. We have previously shown that 1558 genes are differentially expressed in the lungs of bleomycin treated mice. Of the 1412 targets of upregulated microRNAs, 142 were confirmed to be downregulated in the gene expression profile (GEP). Of the 583 targets of downregulated microRNAs, 53 were confirmed to be upregulated in the gene expression profile. Pathway analysis of the microRNA targets and GEP overlapping genes indicated that altered microRNA expression is associated with cellular development, cellular growth, cellular proliferation and changed tissue/cell morphology. Specific pathways include HGF signaling, Cholecystokinin/Gastrin-mediated signaling, Endothelin-1 signaling, RAR activation, Phospholipase C signaling and IGF1 signaling. We conclude that altered microRNA expression is a feature of pulmonary fibrosis which putatively influences components of the altered airway disease. Two condition study, C57Bl/6J mice treated with 100 Units/kg bleomycin and untreated controls. Biological replicated n =3 for each group. Left lung tissue.
Project description:We conducted fibroblast-specific transcriptome analysis by next generation sequencing in order to investigate qualitative change and activation signatures of lung fibroblasts in bleomycin-induced pulmonary fibrosis. Lung fibroblasts were identified by using reporter mice of collagen-α2(I), in which collagen I-producing fibroblasts were labeled with EGFP. Lungs were dissociated with protease sollution, and single cell suspension were stained with lineage markers (Ter119, CD45, CD31, EpCAM). Lineage- GFP+ cells were sorted out and mRNA was collected. Using serial analysis of gene expression (SAGE) method, we identified 2,973,937 SAGE tags (1,080,798 tags from saline-treated GFP+ fibroblasts and 1,893,139 tags from bleomycin-treated GFP+ fibroblasts). We found that genes related to extracellular matrix construction were highly up-regulated in fibroblasts from belomycin-treated lungs. Moreover, an analysis of mRNA profiles revealed biological functions such as proliferation, invasion, adhesion, and migration were promoted in fibroblasts from bleomycin-treated lung, which recapitulated the role of fibroblasts in the fibrogenesis. These fibroblast-specific gene expression profiles will be important notions in future fibrosis studies.
Project description:The molecular mechanisms of lung injury and fibrosis are incompletely understood. microRNAs (miRNAs) are crucial biological regulators by suppression of their target genes and are involved in a variety of pathophysiologic processes. To gain insight into miRNAs in the regulation of lung fibrosis, total RNA was isolated from lung samples harvested at different days after bleomycin treatment, and miRNA array was performed thereafter. miRNAs expressed in lungs with bleomycin treatment at different time points were compared to miRNAs expressed in lungs without bleomycin treatment, resulting in 161 miRNAs differentially expressed. Furthermore, miRNA expression patterns regulated in initial and late periods after bleomycin were identified. Target genes were predicted in silico for differentially expressed miRNAs, including miR-7f, miR-7g, miR-196b, miR-16, miR-195, miR-25, miR-144, miR-351, miR-34a, miR-499, miR-704, miR-717, miR-10a, miR-211, miR-34a, miR-367 and miR-21, and then cross-referenced to molecular pathways including apoptosis, Wnt, Toll-like receptor, and TGF-β signaling, which are involved in different pathological phenotypes such as apoptosis, inflammation, and fibrosis. Our study demonstrated relative abundance of miRNA levels in bleomycin-induced lung fibrosis. The miRNAs and their potential target genes identified herein contribute to the understanding of the complex transcriptional program of lung fibrosis.
Project description:Investigation of whole genome gene expression level changes in Bleomycin induced pulmonary fibrosis mouse model lung tissue, compared to the Sham group.
Project description:Bleomycin-induced pulmonary fibrosis in mice mimics major hallmarks of idiopathic pulmonary fibrosis, yet in this model it spontaneously resolves over time. We studied molecular mechanisms of fibrosis resolution and lung repair, focusing on transcriptional and proteomic signatures and the effect of aging. Young (3 months) and old (21 months) mice were treated with Bleomycin or with control saline solution and analyzed transcript and protein expression over 8 weeks (Day 0, 14, 21, 28, 35, 42, 49, 56).
Project description:Bleomycin-induced pulmonary fibrosis in mice mimics major hallmarks of idiopathic pulmonary fibrosis, yet in this model it spontaneously resolves over time. We studied molecular mechanisms of fibrosis resolution and lung repair, focusing on transcriptional and proteomic signatures and the effect of aging. Young (3 months) and old (21 months) mice were treated with Bleomycin or with control saline solution and analyzed transcript and protein expression over 8 weeks (Day 0, 14, 21, 28, 35, 42, 49, 56).