Project description:Background: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is the most common cause of acute respiratory deterioration and death in IPF patients, with an elusive etiology and pathogenesis. Roles of noncoding RNAs in AE-IPF have been proposed, however, it was rare to find studies have systematically investigated the crosstalk among various transcripts until now. The construction of RNA functional networks such as lncRNA-miRNA-mRNA and circRNA-miRNA-mRNA interaction networks could therefore facilitate our understanding of RNA interactions in AE-IPF. The study aimed to identify the expression differences of RNA transcripts in RNA sequencing from AE-IPF patients and stable IPF (S-IPF), and further to construct the potential RNA networks. Methods: Five AE-IPF patients and five S-IPF were recruited in this study to perform RNA sequencing and miRNA sequencing. The differentially expression profiles of lncRNAs, circRNAs, miRNAs and mRNAs between AE-IPF and S-IPF patients were identified for further analyses. Gene Oncology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis of were performed. The competing endogenous RNAs (ceRNAs) network of lncRNA/circRNA-miRNA-mRNA was constructed, and the core regulatory molecules in the ceRNA network were analyzed. Results: A total of 69 lncRNAs, 150 circRNAs, 27 miRNAs and 56 mRNAs were differentially expressed between AE-IPF and S-IPF. GO and KEGG analysis show that differentially expression mRNAs are significantly associated with tight junction and Hepatitis C, etc. In the ceRNA network, all nodes are directly or indirectly involved in the progression of AE-IPF. 1 lncRNAs, 6 circRNAs, 1 miRNAs, and 5 mRNAs constituted a hsa-miR-150-5p core sub-network. Based on the analysis of ceRNA sub-network, NR_120628/hsa-miR-150-5p/E2F3 and has-circ-0053515/hsa-miR-150-5p/E2F3 were considered to be the key ceRNA axis. Conclusions: In conclusion, this study reveals NR_120628/hsa-miR-150-5p/E2F3 and has-circ-0053515/hsa-miR-150-5p/E2F3 may be the key ceRNA axis in the regulation of AE-IPF, providing clues for future studies on their roles for AE-IPF. Our findings will help to explore the pathological mechanism of AE-IPF from a transcriptomic perspective and provide enlightenment for the biomarker and therapeutic targets of AE-IPF.
Project description:MicroRNAs (miRs) are a class of non-coding RNAs of ~22nt long that play an important role in regulating gene expression at a post-transcriptional level. Aberrant levels of miRs have been associated with profibrotic processes in idiopathic pulmonary fibrosis (IPF). However, the majority of these studies used whole IPF tissue or in vitro monocultures in which fibrosis has been artificially induced. In this study, we used laser microdissection to collect fibroblastic foci (FF), the key pathological lesion in IPF, then isolate miRs and compare their expression levels to those found in whole IPF lung tissue and/or in vitro cultured fibroblast from IPF or normal lungs. Methods – LCM was utilised on formalin embedded IPF tissue to isolate multiple FF and isolate miRs. Libraries were generated and sequenced; data were bioinformatically analysed and Ingenuity Pathway Analysis (IPA) used for integration. Results - Our analysis revealed a total of 49 miRs differentially expressed in FF, of which only 7 were also differentially expressed in in vitro cultured fibroblast. This approach uncovered novel miRs that could be related to IPF. Conclusion - miR expression analyses in LCM isolated FF were able to identify up to 40 miRs not previously described in IPF. Differential expression of these miRs could potentially contribute to IPF development and progression.
Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic fibrosing lung disease that is difficult to diagnose and follows an unpredictable clinical course. The object of this study was to develop a predictive gene signature model of IPF from whole lung tissue. We collected whole lung samples from 11 IPF patients undergoing diagnostic surgical biopsy or transplantation. Whenever possible, samples were obtained from different lobes. Normals consisted of healthy organs donated for transplantation. We measured gene expression on microarrays. Data were analyzed by hierarchical clustering and Principal Component Analysis. By this approach, we found that gene expression was similar in the upper and lower lobes of individuals with IPF. We also found that biopsied and explanted specimens contained different patterns of gene expression; therefore, we analyzed biopsies and explants separately. Signatures were derived by fitting top genes to a Bayesian probit regression model. We developed a 153-gene signature that discriminates IPF biopsies from normal. We also developed a 70-gene signature that discriminates IPF explants from normal. Both signatures were validated on an independent cohort. The IPF Biopsy signature correctly diagnosed 76% of the validation cases (p < 0.01), while IPF Explant correctly diagnosed 78% (p < 0.001). Examination of differentially expressed genes revealed partial overlap between IPF Biopsy and IPF Explant and almost no overlap with previously reported IPF gene lists. However, several overlapping genes may provide a basis for developing therapeutic targets. 17 samples from 11 patients with IPF (6 patients provided a pair of samples from upper and lower lobes; 5 patients contributed singleton samples); 6 control specimens were obtained from routine lung volume reduction of healthy donor lungs at the time of lung transplantation.
Project description:Accelerated senescence in lung epithelial cells is known to play a key role in the pathogenesis of idiopathic pulmonary fibrosis (IPF). However, the exact mechanisms underlying the IPF-related epithelial cell phenotype have yet to be elucidated. Increasing evidence supports the concept that extracellular vesicles (EVs), including exosomes and microvesicles, mediate intercellular communication that contributes to diverse aspects of physiology and pathogenesis. Here, we demonstrate that lung fibroblasts (LFs) from IPF patients accelerate epithelial cell senescence via EV-mediated transfer of LF-derived pathogenic cargo to lung epithelial cells. Mechanistically, IPF LF-derived EVs increase mitochondrial reactive oxygen species (mtROS) and associated mitochondrial damage in lung epithelial cells, leading to mtROS-mediated activation of the DNA damage response and subsequent epithelial cell senescence. We show that IPF LF-derived EVs contain elevated levels of miR-23b-3p and miR-494-3p that are responsible for suppressing SIRT3, resulting in the EV-induced phenotypic changes of lung epithelial cells. Furthermore, we observe that miR-23b-3p and miR-494-3p expression increases in lung epithelial cells from IPF patients’ lungs. Finally, the levels of miR-23b-3p and 494-3p found in IPF LF-derived EVs correlate positively with IPF disease severity. These findings reveal that the accelerated epithelial cell mitochondrial damage and senescence observed during IPF pathogenesis are caused by a novel mechanism in which SIRT3 is suppressed by miR-containing EVs derived from IPF fibroblasts.
Project description:Idiopathic pulmonary fibrosis (IPF) is a fatal form of interstitial lung disease in which persistent injury results in scar tissue formation. As fibrosis thickens, the lung tissue becomes stiff and losses the ability to facilitate gas exchange and provide cells with needed oxygen. Currently, IPF has few treatment options and no effective therapies, aside from lung transplant. Here we present a series of studies utilizing lung spheroid cell-derived conditioned media (LSC-CM) and exosomes (LSC-EXO) to treat different rodent models of lung injury and fibrosis. Inhalation treatment was given for seven consecutive days via a nebulizer for clinical relevance. Results revealed that LSC-CM and LSC-EXO treatments could attenuate and resolve bleomycin- and silica-induced fibrosis by reestablishing normal alveolar structure, decreasing collagen accumulation, and myofibroblast proliferation. In addition, LSC-CM and LSC-EXOs exhibited superior therapeutic benefits than their counterparts derived from bone marrow mesenchymal stem cells. LSC-CM and LSC-EXOs provide promising therapeutic options for pulmonary fibrosis.
Project description:To further understand the pathologic microenvironment in IPF, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to distinguish normal and IPF lung in normal-looking, fibrotic foci and hyperplastic areas of IPF lung. Four IPF lungs were dissected into normal-looking, fibrotic foci and hyperplastic areas by Laser-Capture-Microdissection. Gene expression analysis showed that 638 significantly different genes were identified that clearly distinguished the different IPF microenvironments . Among them, MMP19 was revealed as one of the most significantly up-regulated genes that distinguished normal looking epithelial cells (N) to hyperplastic epithelial cells, MMP19 up-regulation in IPF lungs was verified by immunohistochemical (IHC), qRT-PCR and Western-blot. IPF lungs are heterogeneity complex, which comprise normal looking area, fibrotic foci and hyperplastic area. In this study we separated the normal, fibrotic foci and hyperplastic area by LCM and employed Agilent whole genome gene expression microarray profiling to identify genes with the potential to distinguish the unique microenironment of IPF
Project description:Idiopathic pulmonary fibrosis (IPF) is a specific form of chronic, progressive fibrosing interstitial disease of unknown cause. It remains impractical to conduct early diagnosis and predict IPF progression just based on gene expression information. Moreover, the relationship between gene expression and quantitative phenotypic value in IPF keeps controversial. To identify biomarkers to predict survival in IPF, we profiled protein-coding gene expression in peripheral blood mononuclear cells (PBMCs). We linked the gene expression level with the quantitative phenotypic variation in IPF, including diffusing capacity of the lung for carbon monoxide (DLCO) and forced vital capacity (FVC) percent predicted. In silico analyses on the expression profiles and quantitative phenotypic data allowed for the generation of a set of IPF molecular signature that predicted survival of IPF effectively. Total RNA was isolated from PBMCs using standard molecular biology protocols without DNA contamination or RNA degradation. Sample processing (e.g., cDNA generation, fragmentation, end labeling, hybridization to Affymetrix GeneChip Human Exon 1.0 ST arrays) was performed per manufacturer’s instructions. A total of 45 healthy controls and 70 IPF patients were included in the microarray analysis.
Project description:Objectives: Idiopathic pulmonary fibrosis (IPF) is a complex disease in which a multitude of proteins and networks are disrupted. Interrogation of genome-wide transcription through RNA sequencing (RNA-Seq) enables the determination of genes whose differential expression is most significant in IPF, as well as the detection of alternative splicing events which are not easily observed with traditional microarray experiments. Methods: Messenger RNA extracted from 8 IPF lung samples and 7 healthy controls was sequenced on an Illumina HiSeq. Analysis of differential expression and exon usage was performed using Bioconductor packages. The gene periostin was selected for validation of alternative splicing by quantitative PCR, and pathway analysis was performed to determine enrichment for differentially expressed and spliced genes. Results: There were 873 genes differentially expressed in IPF (FDR 5%), and 440 unique genes had significant differential splicing events (FDR 5%). In particular, cassette exon 21 of the gene periostin was significantly more likely to be spliced out in IPF samples (adj pval = 2.06e-09), and this result was confirmed by qPCR (Wilcoxon pval = 3.11e-4). We also found that genes close to SNPs in the discovery set of a recent IPF GWAS were enriched for genes differentially expressed in our data, including genes like mucin5B and desmoplakin which have been previously associated with IPF. Conclusions: There is significant differential splicing and expression in IPF lung samples as compared with healthy controls. We found a strong signal of differential cassette exon usage in periostin, an extracellular matrix protein whose increased gene-level expression has been associated with IPF and its clinical progression, but for which differential splicing has not been studied in the context of IPF. Our results suggest that alternative splicing of periostin and other genes may be involved in the pathogenesis of IPF. mRNA sequencing of 8 IPF and 7 control lung tissue samples.
Project description:Peripheral blood biomarkers are needed to identify and determine the extent of idiopathic pulmonary fibrosis (IPF). Current physiologic and radiographic prognostic indicators diagnose IPF too late in the course of disease. These results demonstrate that the peripheral blood transcriptome can distinguish normal individuals from patients with IPF, as well as extent of disease when samples were classified by percent predicted DLCO, but not FVC. Gene expression profiles of peripheral blood RNA from 93 IPF patients were collected on Agilent microarrays. Blood was collected in PAXRNA tubes. 30 healthy controls are compared to IPF patients classified by disease severity when categorized by DLCO or FVC.
Project description:Idiopathic pulmonary fibrosis (IPF) is an untreatable fibrotic lung disease characterized by fibroblast proliferation and epithelial mesenchymal transition. The expression and role of microRNAs (miRNA) has not been studied in IPF. Using miRNA expression microarrays we identified 46 differentially expressed miRNA in IPF lungs which included let-7d and the miR-30 family. Keywords: miRNA expression