Development of gene expression signatures for Mmp19 regulation of fibroblast phenotype in mouse lungs
ABSTRACT: We have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to distinguish Mmp19 regulation of fibroblast phenotype changes in mouse lungs. Pulmonary fibrosis was induced by bleomycin at 0.08 u in 50ul of saline. At 21st day the mice were sacrificed and mouse lung fibroblasts were isolated and cultured in FBM plus additives following Lonza's portocol. RNA was extracted with miRNA mini kit from Qiagen. Gene expression microarray was performed with Agilent. A 834-gene consensus signature was identified that distinguished between Mmp19 knockout mice from wildtype. Some gene expression in the same RNA samples were validtaed by real-time PCR. The established bleomycin induced fibrosis was used in this experiment. At day 21 the fibrosis would be the situation of stable fibrosis. We administrated 0.08u of bleomycin intratracheally into wildtype and Mmp19 knockout mice, sacrificed the mice at 21st day and isolated the lung fibroblasts and culturing. Five independent experiments were performed and 3 for gene expression experiment.
Project description:Pulmonary fibrosis (PF) is a life-threatening interstitial lung disease. In this study, we tried to reveal the model of action between high-mobility group box 1 (HMGB1) and ?-smooth muscle actin (?-SMA) and the protective role of gefitinib in pulmonary fibrosis induced by the administration of bleomycin aerosol in mice. For the mechanism study, lung tissues were harvested two weeks after modeling to detect the coexpression of HMGB1 and ?-SMA by immunohistochemistry and immunofluorescence staining. Protein-DNA interactions were analyzed using a pulldown assay to study the relationship between HMGB1 and ?-SMA. For the gefitinib treatment study, the mice were divided into three groups: phosphate-buffered saline (PBS) control group, PBS-treated PF group, and gefitinib-treated PF group. Gavage of gefitinib or PBS (20?mg/kg/day) was performed after bleomycin treatment for two weeks until the mice were sacrificed. Lung and blood samples were collected to assess the histological changes, oxidative stress, and expression of NOXs, HMGB1, EGFR, MAPKs, AP-1, and NF-?B to determine the curative effect and related molecular mechanisms. The results revealed the high coexpression of ?-SMA and HMGB1 in some interstitial cells in the fibrotic lung. The DNA-protein pulldown analysis proved that HMGB34367 acted as a novel transcriptional factor for the ?-SMA promoter and participated in the eventual development of pulmonary fibrosis. Second, gefitinib could significantly decrease lung fibrotic changes and the level of MDA and recover the T-AOC level. Meanwhile, gefitinib could also reduce the NOX1/2/4, HMGB1, p-EGFR, p-ERK, p-JNK, p-P38, p-NF-?B, p-c-Jun, and p-c-Fos expression levels in fibrotic lungs. The present study suggested that gefitinib could alleviate lung fibrosis through the HMGB1/NOXs-ROS/EGFR-MAPKs-AP-1/NF-?B signal in bleomycin-induced pulmonary fibrosis.
Project description:BACKGROUND:Idiopathic Pulmonary Fibrosis (IPF) is a progressive diffuse disease involving the lung parenchyma. Despite recent advances, the molecular mechanisms of the initiation and progression of this disease remain elusive. Previous studies have demonstrated TGFbeta1 as a key effector cytokine in the development of lung fibrosis. METHODS:In this study we have used a transgenic mouse based strategy to identify the effect of overexpression of this key effector mediator on the development of pulmonary fibrosis in response to exogenous injury. We bred two lines (line 25 and 18) of transgenic mice (Tr+) that overexpressed active TGFbeta1. Three-month old transgenic and wild type mice were subsequently wounded with intraperitoneal bleomycin. Mice were sacrificed at 6 weeks post-bleomycin and their lungs analysed histologically and biochemically. RESULTS:The severity of lung fibrosis was significantly greater in the Tr+ mice compared to the wild type mice. Using an oligonucleotide microarray based strategy we identified discrete patterns of gene expression contributing to TGFbeta1 associated pulmonary fibrosis. CONCLUSION:This data emphasises the importance of a host predisposition in the form of endogenous TGFbeta1, in the development of pulmonary fibrosis in response to an exogenous injury.
Project description:Although C/EBP?(ko) mice are refractory to Bleomycin-induced lung fibrosis the molecular mechanisms remain unknown. Here we show that blocking the ribosomal S-6 kinase (RSK) phosphorylation of the CCAAT/Enhancer Binding Protein (C/EBP)-? on Thr217 (a RSK phosphoacceptor) with either a single point mutation (Ala217), dominant negative transgene or a blocking peptide containing the mutated phosphoacceptor ameliorates the progression of lung injury and fibrosis induced by Bleomycin in mice.Mice expressing the non-phosphorylatable C/EBP?-Ala217 transgene had a marked reduction in lung injury on day-13 after Bleomycin exposure, compared to C/EBP?(wt) mice, judging by the decrease of CD68(+) activated monocytes/macrophages, bone marrow-derived CD45(+) cells and lung cytokines as well as by the normal surfactant protein-C expression by lung pneumocytes. On day-21 after Bleomycin treatment, C/EBP?(wt) mice but not mice expressing the dominant negative C/EBP?-Ala217 transgene developed severe lung fibrosis as determined by quantitative collagen assays. All mice were of identical genetic background and back-crossed to the parental wild-type inbreed FVB mice for at least ten generations. Treatment of C/EBP?(wt) mice with a cell permeant, C/EBP? peptide that inhibits phosphorylation of C/EBP? on Thr217 (40 µg instilled intracheally on day-2 and day-6 after the single Bleomycin dose) also blocked the progression of lung injury and fibrosis induced by Bleomycin. Phosphorylation of human C/EBP? on Thr266 (human homologue phosphoacceptor) was induced in collagen-activated human lung fibroblasts in culture as well as in activated lung fibroblasts in situ in lungs of patients with severe lung fibrosis but not in control lungs, suggesting that this signaling pathway may be also relevant in human lung injury and fibrosis.These data suggest that the RSK-C/EBP? phosphorylation pathway may contribute to the development of lung injury and fibrosis.
Project description:BACKGROUND: Antiflammin-1 (AF-1), a derivative of uteroglobin (UG), is a synthetic nonapeptide with diverse biological functions. In the present study, we investigated whether AF-1 has a protective effect against bleomycin-induced pulmonary fibrosis. METHODS: C57BL/6 mice were injected with bleomycin intratracheally to create an animal model of bleomycin-induced pulmonary fibrosis. On Day 7 and Day 28, we examined the anti-inflammatory effect and antifibrotic effect, respectively, of AF-1 on the bleomycin-treated mice. The effects of AF-1 on the transforming growth factor-beta 1 (TGF-β1)-induced proliferation of murine lung fibroblasts (NIH3T3) were examined by a bromodeoxycytidine (BrdU) incorporation assay and cell cycle analysis. RESULTS: Severe lung inflammation and fibrosis were observed in the bleomycin-treated mice on Day 7 and Day 28, respectively. Administration of AF-1 significantly reduced the number of neutrophils in the bronchoalveolar lavage fluid (BALF) and the levels of tumor necrosis factor-alpha (TNF-α) and interleukin-1 beta (IL-1β) in the lung homogenates on Day 7. Histological examination revealed that AF-1 markedly reduced the number of infiltrating cells on Day 7 and attenuated the collagen deposition and destruction of lung architecture on Day 28. The hydroxyproline (HYP) content was significantly decreased in the AF-1-treated mice. In vitro, AF-1 inhibited the TGF-β1-induced proliferation of NIH3T3 cells, which was mediated by the UG receptor. CONCLUSIONS: AF-1 has anti-inflammatory and antifibrotic actions in bleomycin-induced lung injury. We propose that the antifibrotic effect of AF-1 might be related to its suppression of fibroblast growth in bleomycin-treated lungs and that AF-1 has potential as a new therapeutic tool for pulmonary fibrosis.
Project description:Transcriptional profiling of mouse lungs by comparing PBS and saline treated lungs with SEA and bleomycin treated lungs, respectively. Mice strains used in this study include wild type (C57BL/6), IL-13Ra1 and IL-13Ra2 deficient mice. In mouse model of allergic asthma, mice were sensitized twice (day0 and day14) by i.p. injection of 10 µg of SEA. On days 28 and 31 mice were anesthetized with a mixture of xylazine and ketamine and given an intratracheal (I.T) airway challenge with 10 µg of SEA. Mice were sacrificed 24 h after the final airway challenge (day 32) and lungs were collected for RNA preparation. Biological replicates include 5 PBS treated and 5 SEA treated mice. In bleomycin-induced fibrosis odel, mice were anaesthetized with a xylazine and ketamine cocktail and given 0.15 U bleomycin sulfate (EMD) in saline or saline alone via the I.T. route. On day 7, mice were sacrificed and ungs were collected for RNA preparation. Biological replicates include 4 saline treated and 4 bleomycin treated mice. Goal was to determine IL-13 receptors regulated genes during SEA induced allergic asthma and bleomycin-induced fibrosis. Fluorescent cDNA targets were prepared from a 20 μg experimental RNA sample (SEA or bleomycin challenged group–dUTPCy5 – Amersham, Piscataway, NJ) and a 20 μg reference RNA sample (PBS or saline treated group–dUTPCy3- Amersham, Piscataway, NJ). Equal quantities of the above labeled cDNA (experimental and reference labeled RNA samples) were mixed and any free label present in the sample was removed by washing 3 times using a 10 kDa cutoff Vivaspin filters (Millipore). Labeled fluorescent cDNA targets were hybridized on the Whole Mouse Genome Oligo Microarray Kit (Agilent, Palo Alto, CA) containing more than 41000 gene probes.
Project description:BACKGROUND:The role of bronchiolar epithelial cells in the pathogenesis of pulmonary fibrosis has not been clarified. We previously demonstrated DNA damage in murine bronchioles in the early stages of bleomycin-induced pulmonary fibrosis that subsequently extended to alveolar cells at the advanced stages of the disease. Club cells are progenitor cells for bronchioles and are known to play protective roles against lung inflammation and damage. The aim of the present study was to elucidate the role of club cells in the development of pulmonary fibrosis. METHODS:C57BL/6 J mice received naphthalene intraperitoneally on day -2 to deplete club cells and were given intratracheal bleomycin or a vehicle on day 0. Lung tissues were obtained on days 1, 7, and 14, and bronchoalveolar lavage was performed on day 14. Bronchiolar epithelial cells sampled by laser capture microdissection were analyzed by gene expression microarray analysis on day 14. RESULTS:Club cell depletion induced by naphthalene protected mice from bleomycin-induced lung injury and fibrosis. Bleomycin-triggered bronchiolar TGF-?1 expression was reduced. Gene expression microarray analysis revealed that genes associated with inflammatory response and chemokine activity were downregulated in the bleomycin-injured bronchiolar epithelium with club cell injury compared to that in bronchiolar epithelium without cell injury. CONCLUSIONS:Club cells are involved in the development of lung injury and fibrosis.
Project description:Acute lung injury results in early inflammation and respiratory distress, and later fibrosis. The glycosaminoglycan hyaluronan (HA) and the Receptor for Hyaluronan-Mediated Motility (RHAMM, CD168) have been implicated in the response to acute lung injury. We hypothesized that, compared to wild type (WT) mice, RHAMM knockout (KO) mice would be protected from, whereas mice with macrophage-specific transgenic overexpression of RHAMM (TG) would have worse inflammation, respiratory distress and fibrosis after intratracheal (IT) bleomycin. Compared to WT mice, 10?days after IT bleomycin, RHAMM KO mice had less weight loss, less increase in respiratory rate, and fewer CD45+ cells in the lung. At day 28, compared to injured WT animals, injured RHAMM KO mice had lower M1 macrophage content, as well as decreased fibrosis as determined by trichrome staining, Ashcroft scores and lung HPO content. Four lines of transgenic mice with selective overexpression of RHAMM in macrophages were generated using the Scavenger Receptor A promoter driving a myc-tagged full length RHAMM cDNA. Baseline expression of RHAMM and CD44 was the same in WT and TG mice. By flow cytometry, TG bone marrow-derived macrophages (BMDM) had increased cell surface RHAMM and myc, but equal CD44 expression. TG BMDM also had 2-fold increases in both chemotaxis to HA and proliferation in fetal bovine serum. In TG mice, increased inflammation after thioglycollate-induced peritonitis was restricted to macrophages and not neutrophils. For lung injury studies, non-transgenic mice given bleomycin had respiratory distress with increased respiratory rates from day 7 to 21. However, TG mice had higher respiratory rates from 4?days after bleomycin and continued to increase respiratory rates up to day 21. At 21?days after IT bleomycin, TG mice had increased lung macrophage accumulation. Lavage HA concentrations were 6-fold higher in injured WT mice, but 30-fold higher in injured TG mice. At 21?days after IT bleomycin, WT mice had developed fibrosis, but TG mice showed exaggerated fibrosis with increased Ashcroft scores and HPO content. We conclude that RHAMM is a critical component of the inflammatory response, respiratory distress and fibrosis after acute lung injury. We speculate that RHAMM is a potential therapeutic target to limit the consequences of acute lung injury.
Project description:A well-characterized mouse model of SSc involves daily subcutaneous injections of the antitumor antibiotic bleomycin (BLM), which leads to localized dermal fibrosis as well as pulmonary fibrosis. We have termed this the “Systemic Bleomycin Model” to distinguish it from the already-established Intratracheal (IT) model. We utilize this model, which mimics several key features of human SSc, to examine the pathological mechanisms underlying the development and progression of fibrosis in SSc. Overall design: Female C57BL/6 mice (~12 weeks old) were used for this study. An electric shaver was used to shave the interscapular region on the back of each mouse, and a non-toxic permanent marker was used to draw two small circles on the skin within the shaved area on each mouse. Fibrosis was induced by daily subcutaneous injections of either bleomycin (10mg/kg/day; 100μl per injection site of 1mg/ml solution for these ~20gm mice) or PBS (vehicle control) within the marked interscapular regions. Injections began on Day 0 and were done five times per week for two weeks, using a 27-gauge needle. (Bhattacharyya S. et al., Sci Transl Med 2014 Apr 16;6(232):232ra50; Huang J. et al., Ann Rheum Dis 2015 Apr 9. pii: annrheumdis-2014-207109). Beginning on Day 12, the ALK5 inhibitor SB525334 (30mpk) or vehicle was delivered (PO, BID dosing). Note that Groups 1-2 and Groups 3-4 were sacrificed on Day 7 and Day 14, respectively, and thus did not receive oral dosing. Groups 5-7 were sacrificed on Day 21. The last oral doses were administered on Day 27. Groups 8-10 were sacrificed on Day 28. Groups 11-12 (which specifically serve to assess resolution in this model, and do not examine the effect of Alk5 inhibition) were sacrificed on Day 42.
Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic disease for which novel approaches are urgently required. We reported increased sphingosine kinase 1 (SPHK1) in IPF lungs and that SPHK1 inhibition using genetic and pharmacologic approaches reduces murine bleomycin-induced pulmonary fibrosis. We determined whether PF543, a specific SPHK1 inhibitor post bleomycin or asbestos challenge mitigates lung fibrosis by reducing mitochondrial (mt) DNA damage and pro-fibrotic monocyte recruitment-both are implicated in the pathobiology of pulmonary fibrosis. Bleomycin (1.5 U/kg), crocidolite asbestos (100 µg/50 µL) or controls was intratracheally instilled in Wild-Type (C57Bl6) mice. PF543 (1 mg/kg) or vehicle was intraperitoneally injected once every two days from day 7-21 following bleomycin and day 14-21 or day 30-60 following asbestos. PF543 reduced bleomycin- and asbestos-induced pulmonary fibrosis at both time points as well as lung expression of profibrotic markers, lung mtDNA damage, and fibrogenic monocyte recruitment. In contrast to human lung fibroblasts, asbestos augmented lung epithelial cell (MLE) mtDNA damage and PF543 was protective. Post-exposure PF543 mitigates pulmonary fibrosis in part by reducing lung epithelial cell mtDNA damage and monocyte recruitment. We reason that SPHK1 signaling may be an innovative therapeutic target for managing patients with IPF and other forms of lung fibrosis.
Project description:Pulmonary fibrosis is a progressive and fatal lung disease with limited therapeutic options. Although it is well known that lipid mediator prostaglandins are involved in the development of pulmonary fibrosis, the role of prostaglandin D2 (PGD2) remains unknown. Here, we investigated whether genetic disruption of hematopoietic PGD synthase (H-PGDS) affects the bleomycin-induced lung inflammation and pulmonary fibrosis in mouse. Compared with H-PGDS naïve (WT) mice, H-PGDS-deficient mice (H-PGDS-/-) represented increased collagen deposition in lungs 14 days after the bleomycin injection. The enhanced fibrotic response was accompanied by an increased mRNA expression of inflammatory mediators, including tumor necrosis factor-?, monocyte chemoattractant protein-1, and cyclooxygenase-2 on day 3. H-PGDS deficiency also increased vascular permeability on day 3 and infiltration of neutrophils and macrophages in lungs on day 3 and 7. Immunostaining showed that the neutrophils and macrophages expressed H-PGDS, and its mRNA expression was increased on day 3and 7 in WT lungs. These observations suggest that H-PGDS-derived PGD2 plays a protective role in bleomycin-induced lung inflammation and pulmonary fibrosis.