Lipoxin A4 Attenuates Bronchopulmonary Dysplasia via Upregulation of Let-7c and Downregulation of TGF-β1 Signaling Pathway
Lipoxin A4 Attenuates Bronchopulmonary Dysplasia via Upregulation of Let-7c and Downregulation of TGF-β1 Signaling Pathway
复制标题
脂氧素A4通过上调Let-7 c和下调TGF-β1信号通路减轻支气管肺发育不良
DOI：
10.1007/s10753-017-0649-7
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发表时间：
2017-12-01
期刊：
影响因子：
5.1
通讯作者：
Sun, Zhong-yi
中科院分区：
文献类型：
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作者：
Chen, Xiao-Qing;Wu, Sheng-Hua;Sun, Zhong-yi
转化生长因子-β（TGF-β）超家族成员是肺发育和支气管肺发育不良（BPD）进展的关键调节因子。脂氧素A（4）（LXA（4））减弱BPD发展的机制尚未阐明。采用高氧诱导新生小鼠BPD模型。将新生小鼠暴露于室内空气或85%O-2高氧环境中，同时给予或不给予5S，6 R-甲基-LXA（4）或抗TGF-β抗体治疗。将小鼠肺上皮细胞（MLE-12细胞）和小鼠胚胎成纤维细胞（NIH/3 T3细胞）在室内空气或85%O-2中培养，随后用LXA（4）、抗TGF-β抗体和let-7 c模拟物/抗microRNA转染处理。用5S，6 R-甲基-LXA（4）和抗TGF-β抗体治疗均减弱了由高氧诱导的小鼠肺泡简化。高氧治疗显著改变了几种重要的细胞外基质（ECM）和ECM重塑蛋白（包括纤连蛋白、α-平滑肌肌动蛋白（α-SMA）、金属蛋白酶组织抑制剂-1（TIMP-1）、弹性蛋白、腱生蛋白C、胶原蛋白I和基质金属蛋白酶-1（MMP-1））的肺基础mRNA和蛋白质表达。5S，6 R-methyl-LXA（4）和抗TGF-β抗体抑制暴露于高氧的肺中TGF-β（1）和TGF-β R1的mRNA和蛋白质表达，但不抑制TGF-β R2。通过形态学观察和流式细胞术鉴定，LXA（4）和抗TGF-β抗体处理减轻了NIH/3 T3细胞的高氧诱导的损伤，以及ECM、ECM重塑蛋白和TGF-β（1）信号通路的表达，但通过let-7 c抗miRNA转染逆转。LXA（4）上调了let-7 c在MLE-12细胞中的表达，用let-7 c anti-miRNA转染，抑制了LXA（4）诱导的暴露于高氧的MLE-12细胞中的let-7 c表达，并降低了let-7 c与TGF-β R1 3' UTR的let-7 c结合位点结合的相对荧光素酶活性。用5S，6 R-甲基-LXA（4）和抗TGF-β抗体治疗显著改善了从高氧诱导的小鼠BPD模型分离的肺中的组织学、ECM和ECM重塑蛋白。LXA（4）对高氧诱导的肺损伤的保护作用是通过上调let-7 c和抑制TGF-β（1）以及随后下调TGF-β（1）信号通路介导的。
Transforming growth factor-beta (TGF-beta) superfamily members are key regulators for lung development and progress of bronchopulmonary dysplasia (BPD). The mechanisms by which lipoxin A(4) (LXA(4)) attenuates development of BPD have not been clarified. Neonatal murine BPD models were inducted by hyperoxia treatment. Neonatal mice were exposed to room air or 85% O-2 hyperoxia with or without treatment with 5S,6R-methyl-LXA(4) or anti-TGF-beta antibodies. Mouse lung epithelial cells (MLE-12 cells) and mouse embryonic fibroblasts (NIH/3T3 cells) were cultured in room air or 85% O-2 followed by treatment of LXA(4), anti-TGF-beta antibodies, and let-7c mimic/anti-microRNA transfections. Treatment with 5S,6R-methyl-LXA(4) and anti-TGF-beta antibodies both attenuated the mice alveolar simplification induced by hyperoxia. Hyperoxia treatment significantly altered pulmonary basal mRNA and protein expressions of several important extracellular matrix (ECM) and ECM remodeling proteins including fibronectin, alpha-smooth muscle actin (alpha-SMA), tissue inhibitor of metalloproteinase-1 (TIMP-1), elastin, tenascin C, collagen I, and matrix metalloproteinase-1 (MMP-1). 5S,6R-methyl-LXA(4) and anti-TGF-beta antibodies suppressed the mRNA and protein expressions of TGF-beta(1) and TGF-beta R1 but not TGF-beta R2 in the lungs exposed to hyperoxia. Treatment with LXA(4) and anti-TGF-beta antibodies alleviated hyperoxia-induced injury of the NIH/3T3 cells identified by morphologic observation and flow cytometry, and expressions of ECM, ECM remodeling proteins, and TGF-beta(1) signaling pathway, but reversed by transfection with let-7c anti-miRNA. LXA(4) upregulated the let-7c expression in MLE-12 cells, transfection with let-7c anti-miRNA, inhibited the LXA(4)-induced let-7c expression in MLE-12 cells exposed to hyperoxia and reduced the relative luciferase activity of let-7c binding with let-7c binding sites of the TGF-beta R1 3' UTR. Treatment with 5S,6R-methyl-LXA(4) and anti-TGF-beta antibodies significantly improved histology, ECM, and ECM remodeling proteins in the lungs isolated from the murine BPD model induced by hyperoxia. The LXA(4)-imparted protective effects on hyperoxia-induced lung injury are mediated by upregulation of let-7c and inhibition of TGF-beta(1) and subsequent downregulation of TGF-beta(1) signaling pathway.