Department of Pulmonary and Critical Care Medicine, Central Hospital of Wuhan, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
Department of Pulmonary and Critical Care Medicine, Central Hospital of Wuhan, Jiang Han University, Wuhan, Hubei, China.
Shock. 2022 Aug 1;58(2):137-146. doi: 10.1097/SHK.0000000000001960. Epub 2022 Jul 24.
Idiopathic pulmonary fibrosis is defined as a specific form of chronic, progressive fibrosing interstitial pneumonia of unknown cause. Interleukin (IL)-11 plays an important role in the pathogenesis of idiopathic pulmonary fibrosis. In this study, we explore whether a potential antifibrotic agent fluorofenidone (FD) exerts its anti-inflammatory and antifibrotic effects through suppressing activation of the IL-11/MEK/ERK signaling pathway in vivo and in vitro. Male C57BL/6 J mice were intratracheally injected with bleomycin or saline. Fluorofenidone was administered throughout the course of the experiment. Lung tissue sections were stained with hemotoxylin and eosin, and Masson trichrome. Cytokines were measured using the enzyme-linked immunosorbent assay. The α-smooth muscle actin (α-SMA), fibronectin, and collagen I were measured using immunohistochemistry, and the phosphorylated extracellular signal-regulated kinase, phosphorylated mitogen-activated protein kinase, IL-11RA, and gp130 were measured using Western blot. The RAW264.7 cells and the normal human lung fibroblasts were treated with IL-11 and/or FD, IL-11RA-siRNA, or MEK inhibitor. The expressions of phosphorylated extracellular signal-regulated kinase, phosphorylated mitogen-activated protein kinase, IL-11RA, gp130, α-SMA, fibronectin, and collagen I were measured using Western blot and/or real-time polymerase chain reaction, and the cytokines were measured using enzyme-linked immunosorbent assay. Results showed that FD markedly reduced the expressions of IL-8, IL-18, IL-11, monocyte chemotactic protein-1, α-SMA, fibronectin, and collagen I in mice lung tissues. In addition, FD attenuated IL-11-induced expressions of α-SMA, fibronectin, and collagen I and inhibited IL-11RA, gp130, and phosphorylation of the ERK and MEK protein expression, as well as reduced the expressions of IL-8, IL-18, and monocyte chemotactic protein-1 in vitro. This study demonstrated that FD attenuated bleomycin-induced pulmonary inflammation and fibrosis in mice by inhibiting the IL-11/MEK/ERK signaling pathway.
特发性肺纤维化被定义为一种原因不明的慢性、进行性纤维性间质性肺炎的特定形式。白细胞介素 (IL)-11 在特发性肺纤维化的发病机制中发挥重要作用。在这项研究中，我们探讨了潜在的抗纤维化剂氟洛芬尼酮 (FD) 是否通过抑制体内和体外的 IL-11/MEK/ERK 信号通路的激活来发挥其抗炎和抗纤维化作用。雄性 C57BL/6 J 小鼠经气管内注射博来霉素或生理盐水。氟洛芬尼酮在整个实验过程中给药。用苏木精和伊红、马松三色染色法对肺组织切片进行染色。使用酶联免疫吸附试验测量细胞因子。使用免疫组织化学法测量α-平滑肌肌动蛋白 (α-SMA)、纤连蛋白和胶原 I，使用 Western blot 法测量磷酸化细胞外信号调节激酶、磷酸化丝裂原激活蛋白激酶、IL-11RA 和 gp130。用 IL-11 和/或 FD、IL-11RA-siRNA 或 MEK 抑制剂处理 RAW264.7 细胞和正常人肺成纤维细胞。使用 Western blot 和/或实时聚合酶链反应测量磷酸化细胞外信号调节激酶、磷酸化丝裂原激活蛋白激酶、IL-11RA、gp130、α-SMA、纤连蛋白和胶原 I 的表达，并使用酶联免疫吸附试验测量细胞因子。结果表明，FD 可显著降低小鼠肺组织中 IL-8、IL-18、IL-11、单核细胞趋化蛋白-1、α-SMA、纤连蛋白和胶原 I 的表达。此外，FD 减弱了 IL-11 诱导的α-SMA、纤连蛋白和胶原 I 的表达，并抑制了 IL-11RA、gp130 和 ERK 和 MEK 蛋白表达的磷酸化，同时减少了体外 IL-8、IL-18 和单核细胞趋化蛋白-1 的表达。本研究表明，FD 通过抑制 IL-11/MEK/ERK 信号通路，减弱博来霉素诱导的小鼠肺炎症和纤维化。
