The role of miR-497-5p in myofibroblast differentiation of LR-MSCs and pulmonary fibrogenesis

Xiang Chen,Kebin Hu,Zou Xiang,Weilin Liu,Yanhong Chu,Chaowen Shi,Ping Dong,Xiaodong Han,Cong Wang

doi:10.1038/srep40958

Abstract

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive and fatal fibrotic lung disease characterized by profound changes in stem cell differentiation, epithelial cell phenotypes and fibroblast proliferation. In our study, we found that miR-497-5p was significantly upregulated both during myofibroblast differentiation of lung resident mesenchymal stem cells (LR-MSCs) and in the lung tissues of a pulmonary fibrosis model. In addition, as determined by luciferase assays and Western blot analysis, reversion-inducing cysteine-rich protein with kazal motifs (Reck) was identified to be one of the target genes of miR-497-5p, and Reck could suppress the expression of matrix metalloproteinase-2 (Mmp2) and Mmp9, which could activate latent transforming growth factor-β1 (TGF-β1). To test the potential therapeutic significance of this miRNA, we modulated the expression of miR-497-5p in LR-MSCs and relevant animal models. The results demonstrated that upregulation of miR-497-5p could induce LR-MSCs to differentiate into myofibroblasts and promote pulmonary fibrogenesis, while inhibition of its expression could effectively retard these processes. In conclusion, our work supports that controlling pulmonary fibrogenesis via inhibition of miR-497-5p expression may provide a potential therapeutic strategy for IPF.

Highlights

Idiopathic pulmonary fibrosis (IPF), which is featured by deterioration of respiratory functions clinically, is one of the most common types of interstitial lung diseases
To determine the differentially expressed miRNAs during the myofibroblast differentiation of lung resident mesenchymal stem cells (LR-MSCs), we performed a miRNA microarray with total RNAs isolated from LR-MSCs harvested on day 7 after transforming growth factor-β1 (TGF-β1) treatment
To validate the results of miRNA profiling, we confirmed the differential expression of these miRNAs via quantitative PCR (Q-PCR) both in LR-MSCs treated with transforming growth factor (TGF)-β1 and lung tissues from mice that had received BLM intratracheally

Summary

Introduction

Idiopathic pulmonary fibrosis (IPF), which is featured by deterioration of respiratory functions clinically, is one of the most common types of interstitial lung diseases. In a bleomycin (BLM)-induced pulmonary fibrosis model, miR-497-5p was upregulated, and suppressing miR-497-5p expression using a lentiviral agent in vivo reduced the expression of fibrotic markers Mmp[2], Mmp[9] and Tgfb[1] via enhancing the expression of Reck, suggesting augmented in vivo lung repair. These data reveal a potential new therapeutic approach for IPF and an intimate interplay among miR-497-5p, Reck, MMPs, TGF-β1 and pulmonary fibrosis

Methods

Results

Conclusion