title: High-Mobility Group Box 1 Mediates Epithelial-to-Mesenchymal Transition in Pulmonary Fibrosis Involving Transforming Growth Factor-β1/Smad2/3 Signaling.
abstract: Epithelial-to-mesenchymal transition (EMT) is a crucial event in the cellular origin of myofibroblasts that secrete extracellular matrix in the progression of pulmonary fibrosis (PF). High-mobility group box 1 (HMGB1) is a novel mediator of EMT. However, whether this process involves the recognized transforming growth factor-β1 (TGF-β1)/Smad signaling that also contributes to EMT in PF has not yet been elucidated. Here, we developed a model of PF induced by bleomycin (BLM) in rats and conducted several simulation experiments in A549 (human) and RLE-6TN (rat) alveolar epithelial cell (AEC) lines to unravel the role of TGF-β1/Smad2/3 signaling in HMGB1-mediated EMT. We found that the levels of serum HMGB1 and lung hydroxyproline were severely elevated after BLM administration. Moreover, the protein expression of HMGB1, TGF-β1, phosphorylated Smad2/3 (p-Smad2/3), and mesenchymal markers including α-smooth muscle actin, vimentin, and type I collagen were significantly increased with the reduced protein expression of an epithelial marker (E-cadherin) in the rat model by Western blot or immunohistochemical analysis. In addition, the uptake of both exogenous TGF-β1 and HMGB1 by AECs could induce EMT; meanwhile, HMGB1 dramatically enhanced TGF-β1 expression and triggered Smad2/3 phosphorylation. In contrast, TGF-β1 deficiency evidently ameliorated HMGB1-mediated EMT with reduced p-Smad2/3 in A549 cells. It provides new insights that HMGB1 release from injured lungs promotes AEC damage through induction of the EMT process, in which TGF-β1/Smad2/3 signaling is activated and contributes to PF. These results suggest that HMGB1 may constitute a therapeutic target for developing antifibrotic agents for abnormal lung remodeling.
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: Liu-Cheng
authors.initials: LC
authors.lastname: Li
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: De-Lin
authors.initials: DL
authors.lastname: Li
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: Liang
authors.initials: L
authors.lastname: Xu
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: Xiao-Ting
authors.initials: XT
authors.lastname: Mo
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: Wen-Hui
authors.initials: WH
authors.lastname: Cui
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: Ping
authors.initials: P
authors.lastname: Zhao
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.).
authors.forename: Wen-Cheng
authors.initials: WC
authors.lastname: Zhou
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.) gaojianayfy@163.com lijun@ahmu.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Gao
authors.affiliation: Department of Pharmacy, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, People's Republic of China (L.-C.L.); The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China (D.-L.L., J.G.); School of Pharmacy, Anhui Medical University, Hefei, People's Republic of China (X.-T.M., W.-H.C., W.-C.Z., J.L.); and School of Pharmacy, Anhui University of Chinese Medicine, Hefei, People's Republic of China (D.-L.L., L.X., P.Z.) gaojianayfy@163.com lijun@ahmu.edu.cn.
authors.forename: Jun
authors.initials: J
authors.lastname: Li
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D015820:Cadherins / Q000378:metabolism; D002460:Cell Line; D045744:Cell Line, Tumor; D024042:Collagen Type I / Q000378:metabolism; D004847:Epithelial Cells / Q000378:metabolism; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology*; D024243:HMGB1 Protein / Q000097:blood / Q000378:metabolism*; D006801:Humans; D006909:Hydroxyproline / Q000378:metabolism; D010766:Phosphorylation / Q000502:physiology; D011658:Pulmonary Fibrosis / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins; D015398:Signal Transduction / Q000502:physiology*; D051899:Smad2 Protein / Q000378:metabolism*; D051900:Smad3 Protein / Q000378:metabolism*; D053773:Transforming Growth Factor beta1 / Q000378:metabolism*; D014746:Vimentin / Q000378:metabolism
chemical_list: D000199:Actins; D015820:Cadherins; D024042:Collagen Type I; D024243:HMGB1 Protein; C585491:HMGB1 protein, human; D011994:Recombinant Proteins; D051899:Smad2 Protein; D051900:Smad3 Protein; D053773:Transforming Growth Factor beta1; D014746:Vimentin; D006909:Hydroxyproline