Wang Yichun, Liu Jingshi, Chen Junyi, Feng Tao, Guo Qulian
Department of Anesthesiology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
Department of Critical Care Medicine, the Affiliated Cancer Hospital of Xiangya Medical School, Central South University, Changsha, Hunan, China.
Technol Health Care. 2015;23 Suppl 1:S119-25. doi: 10.3233/thc-150943.
TGFβ 1 is very important in the synthesis and degradation of extracellular matrix (ECM), and also in the mediation of human pulmonary fibroblasts proliferation, and miR-29 plays an important role in this process.
In the present study, the effects of TGFβ 1 on the expression of miR-29 and whether miR-29 is involved in pro-survival signaling pathways mediated by TGFβ 1 were examined in human pulmonary fibroblasts.
Treatment of the human IMR-90 cells with TGFβ 1 caused a decrease in the expression of miR-29a/b/c as determined by real-time PCR analysis. TGFβ 1 stimulation increased cell proliferation, colony formation and up-regulated expression of COL1A1; transfecting with miR-29a/b/c mimics reverse TGFβ 1-induced phenotype changes in IMR-90. Western blot analyses showed that TGFβ 1 treatment unchanged total protein expression levels of β -catenin, but phosphorylation of β -catenin and the expression levels of wnt3a and COL1A1 were increased; and miR-19a/b/c mimics interfering blocked DKK1, wnt3a, and phosphorylation of β -catenin and decreased expression of COL1A1 after TGFβ 1 treatment. Our results showed that TGFβ 1 activated the wnt/β -catenin pathway, and this activation was essential for the expression of miR-29 in IMR-90.
The results indicate a novel biological function of the wnt/β -catenin pathway in IMR-90. Elevated expression of miR-29 may play an important role in the pathogenesis of diseases related to fibrogenic reactions in human IMR-90.
转化生长因子β1（TGFβ1）在细胞外基质（ECM）的合成与降解以及人肺成纤维细胞增殖的介导过程中非常重要，而微小RNA-29（miR-29）在此过程中发挥重要作用。
在本研究中，检测TGFβ1对人肺成纤维细胞中miR-29表达的影响以及miR-29是否参与由TGFβ1介导的促生存信号通路。
通过实时定量聚合酶链反应分析确定，用TGFβ1处理人胚肺成纤维细胞系IMR-90细胞后，miR-29a/b/c的表达降低。TGFβ1刺激可增加细胞增殖、集落形成并上调Ⅰ型胶原α1（COL1A1）的表达；用miR-29a/b/c模拟物转染可逆转TGFβ1诱导的IMR-90细胞表型变化。蛋白质免疫印迹分析表明，TGFβ1处理后β-连环蛋白的总蛋白表达水平未改变，但β-连环蛋白的磷酸化水平以及wnt3a和COL1A1的表达水平增加；而miR-19a/b/c模拟物干扰可阻断TGFβ1处理后DKK1、wnt3a和β-连环蛋白的磷酸化，并降低COL1A1的表达。我们的结果表明，TGFβ1激活了wnt/β-连环蛋白通路，且这种激活对于IMR-90细胞中miR-29的表达至关重要。
结果表明wnt/β-连环蛋白通路在IMR-90细胞中具有新的生物学功能。miR-29表达升高可能在人IMR-90细胞中与纤维生成反应相关疾病的发病机制中起重要作用。
