Sulforaphane attenuates pulmonary fibrosis by inhibiting the epithelial-mesenchymal transition

Abstract

BackgroundIdiopathic pulmonary fibrosis (IPF) is a progressive and fatal disease with no effective treatment. The epithelial-mesenchymal transition (EMT) is a critical stage during the development of fibrosis. To assess the effect of sulforaphane (SFN) on the EMT and fibrosis using an in vitro transforming growth factor (TGF)-β1-induced model and an in vivo bleomycin (BLM)-induced model.MethodsIn vitro studies, cell viability, and cytotoxicity were measured using a Cell Counting Kit-8. The functional TGF-β1-induced EMT and fibrosis were assessed using western blotting and a quantitative real-time polymerase chain reaction. The lungs were analyzed histopathologically in vivo using hematoxylin and eosin and Masson’s trichrome staining. The BLM-induced fibrosis was characterized by western blotting and immunohistochemical analyses for fibronectin, TGF-β1, E-cadherin (E-cad), and α-smooth muscle actin (SMA) in lung tissues.ResultsSFN reversed mesenchymal-like changes induced by TGF-β1 and restored cells to their epithelial-like morphology. The results confirmed that the expression of the epithelial marker, E-cadherin, increased after SFN treatment, while expression of the mesenchymal markers, N-cadherin, vimentin, and α-SMA decreased in A549 cells after SFN treatment. In addition, SFN inhibited TGF-β1-induced mRNA expression of the EMT-related transcription factors, Slug, Snail, and Twist. The SFN treatment attenuated TGF-β1-induced expression of fibrosis-related proteins, such as fibronection, collagen I, collagen IV, and α-SMA in MRC-5 cells. Furthermore, SFN reduced the TGF-β1-induced phosphorylation of SMAD2/3 protein in A549 cells and MRC-5 cells. BLM induced fibrosis in mouse lungs that was also attenuated by SFN treatment, and SFN treatment decreased BLM-induced fibronectin expression, TGF-β1 expression, and the levels of collagen I in the lungs of mice.ConclusionsSFN showed a significant anti-fibrotic effect in TGF-β-treated cell lines and BLM-induced fibrosis in mice. These findings showed that SFN has anti-fibrotic activity that may be considered in the treatment of IPF.Electronic supplementary materialThe online version of this article (10.1186/s40360-018-0204-7) contains supplementary material, which is available to authorized users.

Yangyin Yiqi Mixture Ameliorates Bleomycin-Induced Pulmonary Fibrosis in Rats through Inhibiting TGF-β1/Smad Pathway and Epithelial to Mesenchymal Transition

“…This is in agreement with Tanjore et al [14], in which the team reported that about one-third of fibroblasts in lung tissues of BLM-induced pulmonary fibrotic mice was derived from type II lung epithelial cells through the process of EMT. EMT is characterized by low expression of epithelial cell markers such as E-cadherin and ZO-1 and overexpression of mesenchymal markers such as α -Smooth muscle actin ( α -SMA) and vimentin [15, 16]. Meanwhile, TGF- β 1 is regarded as an important triggering factor for the onset of pulmonary fibrosis by accelerating the process of transformation of alveolar epithelial cells into mesenchymal myofibroblasts [17, 18].…”

<p>Knockdown of <em>LINC02471</em> Inhibits Papillary Thyroid Carcinoma Cell Invasion and Metastasis by Targeting miR-375</p>

“…Snail is a transcription factor regulating the EMT process, and it could induce EMT through inhibiting the transcription expression of E-Cad. 29,30 N-Cad, a mesenchymal cell marker, does not express in normal epithelial tissues, but its ectopic expression in epithelial tissues can induce EMT, causes tumor cells to develop invasive phenotype and enables distant metastasis. 31,32 The current study showed that knockdown of LINC02471 increased the E-Cad expression level and reduced the N-Cad and Snail expression level in PTC cell lines, suggesting that LINC02471 could enhance the metastasis of PTC by inducing EMT.…”

MicroRNA-133b/EGFR axis regulates esophageal squamous cell carcinoma metastases by suppressing anoikis resistance and anchorage-independent growth

“…Emerging data demonstrate that EMT is the driving force of cancer metastasis [ 38 , 39 ]. During EMT process, the expression of E-cadherin, a epithelial marker, is decreased, while the expressions of mesenchymal markers, Fibronectin, Vimentin, and N-cadherin, are demonstrated to be increased [ 40 ]. According to the present study, the protein levels of Fibronection, Vimentin, and N-cadherin were down-regulated, while E-cadherin level was up-regulated in ESCC cells by miR-133b agomir or shEGFR treatment via targeting modulation of EGFR.…”