TY - JOUR
T1 - Osteopontin silencing attenuates bleomycin-induced murine pulmonary fibrosis by regulating epithelial–mesenchymal transition
AU - Hatipoglu, Omer Faruk
AU - Uctepe, Eyyup
AU - Opoku, Gabriel
AU - Wake, Hidenori
AU - Ikemura, Kentaro
AU - Ohtsuki, Takashi
AU - Inagaki, Junko
AU - Gunduz, Mehmet
AU - Gunduz, Esra
AU - Watanabe, Shogo
AU - Nishinaka, Takashi
AU - Takahashi, Hideo
AU - Hirohata, Satoshi
N1 - Funding Information:
This study was supported by grants from the Scientific and Technological Research Council of Turkey (TÜBİTAK, Grant no: 113S947 ), a Grant-in-Aid for Scientific Research (A) JSPS KAKENHI (Grant Number 20H00548 to S.H.) and Grant-in-Aid for Scientific Research (C) (Grant Numbers 17K11009 to OFH, 19K09627 to TO, and 19K11791 to JI) from the Japan Society for the Promotion of Science .
Publisher Copyright:
© 2021 The Authors
PY - 2021/7
Y1 - 2021/7
N2 - Idiopathic pulmonary fibrosis (IPF) is the most common and most deadly form of interstitial lung disease. Osteopontin (OPN), a matricellular protein with proinflammatory and profibrotic properties, plays a major role in several fibrotic diseases, including IPF; OPN is highly upregulated in patients’ lung samples. In this study, we knocked down OPN in a bleomycin (BLM)-induced pulmonary fibrosis (PF) mouse model using small interfering RNA (siRNA) to determine whether the use of OPN siRNA is an effective therapeutic strategy for IPF. We found that fibrosing areas were significantly smaller in specimens from OPN siRNA-treated mice. The number of alveolar macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid was also reduced in OPN siRNA-treated mice. Regarding the expression of epithelial–mesenchymal transition (EMT)-related proteins, the administration of OPN-siRNA to BLM-treated mice upregulated E-cadherin expression and downregulated vimentin expression. Moreover, in vitro, we incubated the human alveolar adenocarcinoma cell line A549 with transforming growth factor (TGF)-β1 and subsequently transfected the cells with OPN siRNA. We found a significant upregulation of Col1A1, fibronectin, and vimentin after TGF-β1 stimulation in A549 cells. In contrast, a downregulation of Col1A1, fibronectin, and vimentin mRNA levels was observed in TGF-β1-stimulated OPN knockdown A549 cells. Therefore, the downregulation of OPN effectively reduced pulmonary fibrotic and EMT changes both in vitro and in vivo. Altogether, our results indicate that OPN siRNA exerts a protective effect on BLM-induced PF in mice. Our results provide a basis for the development of novel targeted therapeutic strategies for IPF.
AB - Idiopathic pulmonary fibrosis (IPF) is the most common and most deadly form of interstitial lung disease. Osteopontin (OPN), a matricellular protein with proinflammatory and profibrotic properties, plays a major role in several fibrotic diseases, including IPF; OPN is highly upregulated in patients’ lung samples. In this study, we knocked down OPN in a bleomycin (BLM)-induced pulmonary fibrosis (PF) mouse model using small interfering RNA (siRNA) to determine whether the use of OPN siRNA is an effective therapeutic strategy for IPF. We found that fibrosing areas were significantly smaller in specimens from OPN siRNA-treated mice. The number of alveolar macrophages, neutrophils, and lymphocytes in bronchoalveolar lavage fluid was also reduced in OPN siRNA-treated mice. Regarding the expression of epithelial–mesenchymal transition (EMT)-related proteins, the administration of OPN-siRNA to BLM-treated mice upregulated E-cadherin expression and downregulated vimentin expression. Moreover, in vitro, we incubated the human alveolar adenocarcinoma cell line A549 with transforming growth factor (TGF)-β1 and subsequently transfected the cells with OPN siRNA. We found a significant upregulation of Col1A1, fibronectin, and vimentin after TGF-β1 stimulation in A549 cells. In contrast, a downregulation of Col1A1, fibronectin, and vimentin mRNA levels was observed in TGF-β1-stimulated OPN knockdown A549 cells. Therefore, the downregulation of OPN effectively reduced pulmonary fibrotic and EMT changes both in vitro and in vivo. Altogether, our results indicate that OPN siRNA exerts a protective effect on BLM-induced PF in mice. Our results provide a basis for the development of novel targeted therapeutic strategies for IPF.
KW - Epithelial–mesenchymal transition
KW - Osteopontin
KW - Pulmonary fibrosis
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U2 - 10.1016/j.biopha.2021.111633
DO - 10.1016/j.biopha.2021.111633
M3 - Article
C2 - 34243624
AN - SCOPUS:85110470676
VL - 139
JO - Biomedicine and Pharmacotherapy
JF - Biomedicine and Pharmacotherapy
SN - 0753-3322
M1 - 111633
ER -