title: Neotuberostemonine attenuates bleomycin-induced pulmonary fibrosis by suppressing the recruitment and activation of macrophages.
abstract: Neotuberostemonine (NTS) is one of the main antitussive alkaloids in the root of Stemona tuberosa Lour. This study aimed to investigate the effects of NTS on bleomycin (BLM)-induced pulmonary fibrosis in mice and the underlying mechanism. After BLM administration, NTS were orally administered to mice at 20 and 40mg/kg per day from days 8 to 21, with nintedanib as a positive control. The effect of NTS on BLM-induced mice was assessed via histopathological examination by HE and Masson's trichrome staining, TGF-β1 level and macrophage recruitment by immunohistochemical staining, expression of profibrotic media and M1/M2 polarization by western blot. RAW 264.7 cells were used to evaluate whether NTS (1, 10, 100μM) directly affected macrophages. The results revealed that NTS treatment significantly ameliorated lung histopathological changes and decreased inflammatory cell counts in the bronchoalveolar lavage fluid. The over-expression of collagen, α-SMA and TGF-β1 was reduced by NTS. Furthermore, NTS markedly lowered the expression of MMP-2 and TIMP-1 while raised the expression of MMP-9. A further analysis showed that NTS was able to decrease the recruitment of macrophages and to inhibit the M2 polarization in mice lung tissues. The experiment in vitro showed that NTS significantly reduced the arginase-1 (marker for M2) expression in a dose-dependent manner but down-regulated the iNOS (marker for M1) expression only at 100μM. In conclusion, our study demonstrated for the first time that NTS has a significant protective effect on BLM-induced pulmonary fibrosis through suppressing the recruitment and M2 polarization of macrophages.
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Xiang
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China.
authors.forename: Si
authors.initials: S
authors.lastname: Cheng
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China.
authors.forename: Tianlong
authors.initials: T
authors.lastname: Feng
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China.
authors.forename: Weina
authors.initials: W
authors.lastname: Xie
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China. Electronic address: mianzhang@126.com.
authors.forename: Mian
authors.initials: M
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China.
authors.forename: Xianghong
authors.initials: X
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, China Pharmaceutical University, Nanjing 211198, China. Electronic address: njchaofeng@126.com.
authors.forename: Chaofeng
authors.initials: C
authors.lastname: Zhang
mesh_terms: D000470:Alkaloids / Q000627:therapeutic use*; D000818:Animals; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use*; D001761:Bleomycin; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D006801:Humans; D007165:Immunosuppression Therapy; D007783:Lactones / Q000627:therapeutic use*; D008262:Macrophage Activation / Q000187:drug effects; D016676:Macrophages, Alveolar / Q000187:drug effects* / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000188:drug therapy*; D041901:Stemonaceae / Q000276:immunology*
chemical_list: D000470:Alkaloids; D000893:Anti-Inflammatory Agents; D007783:Lactones; C468415:neotuberostemonine; D001761:Bleomycin
keywords: M2 polarization; Macrophage; Neotuberostemonine; Pulmonary fibrosis; Stemona tuberosa