Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic and often fatal pulmonary disorder characterized by fibroblast proliferation and the excess deposit of extracellular matrix proteins. The etiology of IPF is unknown, but a central role for microRNAs (miRNAs), a class of small non-coding regulatory RNAs, has been recently suggested. We report the upregulation of miR-199a-5p in mouse lungs undergoing bleomycin-induced fibrosis and also in human biopsies from IPF patients. Levels of miR-199a-5p were increased selectively in myofibroblasts and putative profibrotic effects of miR-199a-5p were further investigated in cultured lung fibroblasts. MiR-199a-5p expression was induced upon TGFβ exposure and ectopic expression of miR-199a-5p was sufficient to promote the pathogenic activation of pulmonary fibroblasts. CAV1, a critical mediator of pulmonary fibrosis, was established as a bona fide target of miR-199a-5p. Finally, we also found an aberrant expression of miR-199a-5p in mouse models of kidney and liver fibrosis, suggesting that dysregulation of miR-199a-5p represents a general mechanism contributing to the fibrotic process. We propose miR-199a-5p as a major regulator of fibrosis that represents a potential therapeutic target to treat fibroproliferative diseases. This SuperSeries is composed of the SubSeries listed below. Refer to individual Series
Project description:To assess the impact of miR-199a-5p silencing on lung fibrogenesis, LNA-miR-199a-5p (5mg/kg) or control formulated for in vivo delivery was instilled intratracheally 4 days and 2 days before intratracheal administration of bleomycin (1 unit/kg) or PBS as well as 4 days after bleomycin or PBS treatment.
Project description:Idiopathic pulmonary fibrosis (IPF) is a chronic and often fatal pulmonary disorder characterized by fibroblast proliferation and the excess deposit of extracellular matrix proteins. The etiology of IPF is unknown, but a central role for microRNAs (miRNAs), a class of small non-coding regulatory RNAs, has been recently suggested. We report the upregulation of miR-199a-5p in mouse lungs undergoing bleomycin-induced fibrosis and also in human biopsies from IPF patients. Levels of miR-199a-5p were increased selectively in myofibroblasts and putative profibrotic effects of miR-199a-5p were further investigated in cultured lung fibroblasts. MiR-199a-5p expression was induced upon TGFβ exposure and ectopic expression of miR-199a-5p was sufficient to promote the pathogenic activation of pulmonary fibroblasts. CAV1, a critical mediator of pulmonary fibrosis, was established as a bona fide target of miR-199a-5p. Finally, we also found an aberrant expression of miR-199a-5p in mouse models of kidney and liver fibrosis, suggesting that dysregulation of miR-199a-5p represents a general mechanism contributing to the fibrotic process. We propose miR-199a-5p as a major regulator of fibrosis that represents a potential therapeutic target to treat fibroproliferative diseases. This SuperSeries is composed of the SubSeries listed below.
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:To assess whether CAV1 represents the main target associated with miR-199a-5p profibrotic activity, we designed a CAV1 target site blocker (TBS) to specifically disrupt miR-199a-5p interaction with mCAV1 3’UTR. CAV1 TSB (5mg/kg) or control formulated for in vivo delivery (Control TSB) was instilled intratracheally 4 days and 2 days before intratracheal administration of bleomycin (1 unit/kg) or PBS as well as 4 days after bleomycin or PBS treatment.
Project description:From a previous microarray study we developed a small chondrogenesis model. We performed qPCR and measured how knockdown of miR-199a-5p or miR-199b-5p could modulate chondrogenesis. Several experiments were used to determine the parameters of this model. We utilised parameter scan and manual sliding to refine the model. Within are two models - an initial model which only comprises of genes which we have data for, and an enhanced model which expands of the initial model to make more predictions - e.g. how miR-140-5p is indirectly regulated by miR-199a-5p and miR-199b-5p.
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:MicroRNAs (miRNAs) are a class of highly conserved endogenous noncoding single-stranded small RNAs with a length of 18-22 nucleotides. They are involved in regulation at the posttranscriptional and translational levels through the degradation and translation inhibition of messenger RNA (mRNA). It is estimated that at least 60% of all mammalian genes may be regulated by miRNAs. MiRNAs can help uncover the mechanisms of diseases and provide new entry points into therapy. Accumulated evidence has revealed that miRNAs are involved in the pathological process of cardiovascular disease through specific signaling pathways. To investigate the potential miRNAs for myocardial fibrosis post myocardial infarction, rat models of acute myocardial infarction (AMI) were established by ligating the anterior descending branch of the left coronary artery, while sham-operated rats were only threaded without ligation as a control group. There were three rats in each group. Thirteen differentially expressed miRNAs between the two groups were screened and their expression levels in the model group were all higher than those in the control group. The expression of miR-199a-5p was significantly increased in the model group in qRT-PCR, which was consistent with the results of the gene chip. KEGG enrichment analysis showed that the target genes of miR-199a-5p were enriched in the insulin signaling pathway. Furthermore, dual-luciferase reporter assay indicated that miR-199a-5p could negatively regulate the expression of GSK-3β. After transfection, the expression of miR-199a-5p was increased in the miR-199a-5p mimics group. The protein expression of GSK-3β was decreased in CFs transfected with miR-199a-5p mimics. In summary, our study identified miR-199a-5p could promote the progression of myocardial fibrosis after myocardial infarction by targeting GSK-3β, which provides novel targets for diagnosis and treatment of MF. In summary, our research suggests that miR-199a-5p promotes the progression of myocardial fibrosis after myocardial infarction through the activation of the insulin-PI3K/Akt-GSK-3β signaling pathway.
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.