State Key Laboratory of Pharmaceutical Biotechnology, School of Life Science, Nanjing University, Nanjing, 210093, P.R. China.
Jiangsu Engineering Research Center for microRNA Biology and Biotechnology, Nanjing, 210093, P.R. China.
Sci Rep. 2017 Jun 7;7(1):2957. doi: 10.1038/s41598-017-03175-0.
Hepatocyte death, as well as the following inflammatory and fibrogenic signaling cascades, is the key trigger of liver fibrosis. Here, we isolated hepatocytes from CCl-induced fibrotic liver and found that hepatocyte lincRNA-p21 significantly increased during liver fibrosis. The increase of hepatocyte lincRNA-p21 was associated with the loss of miR-30, which can inhibit TGF-β signaling by targeting KLF11. We revealed that lincRNA-p21 modulated miR-30 availability by acting as a competing endogenous RNA (ceRNA). The physiological significance of this interaction is highlighted by the feedback loop, in which lincRNA-p21 works as a downstream effector of the TGF-β signaling to strengthen TGF-β signaling and mediate its role in promoting liver fibrosis by interacting with miR-30. In vivo results showed that knockdown of hepatocyte lincRNA-p21 greatly reduced CCl-induced liver fibrosis and inflammation, whereas ectopic expression of miR-30 in hepatocyte exhibited the similar results. Mechanistic studies further revealed that inhibition of miR-30 impaired the effects of lincRNA-p21 on liver fibrosis. Additionally, lincRNA-p21 promoted hepatocyte apoptosis in vitro and in vivo, whereas the proliferation rate of hepatocyte was suppressed by lincRNA-p21. The pleiotropic roles of hepatocyte lincRNA-p21 suggest that it may represent an unknown paradigm in liver fibrosis and serve as a potential target for therapy.
肝细胞死亡以及随后的炎症和纤维生成信号级联反应是肝纤维化的关键触发因素。在这里,我们从 CCl4 诱导的纤维化肝脏中分离出肝细胞,发现在肝纤维化过程中肝细胞 lincRNA-p21 显著增加。肝细胞 lincRNA-p21 的增加与 miR-30 的丢失有关,miR-30 可以通过靶向 KLF11 来抑制 TGF-β 信号。我们揭示了 lincRNA-p21 通过作为竞争性内源 RNA(ceRNA)来调节 miR-30 的可用性。这种相互作用的生理意义突出表现在反馈回路中,其中 lincRNA-p21 作为 TGF-β 信号的下游效应子发挥作用,通过与 miR-30 相互作用来增强 TGF-β 信号并介导其在促进肝纤维化中的作用。体内结果表明,敲低肝细胞 lincRNA-p21 可显著减少 CCl4 诱导的肝纤维化和炎症,而在肝细胞中外源表达 miR-30 则表现出类似的结果。机制研究进一步表明,抑制 miR-30 会损害 lincRNA-p21 对肝纤维化的影响。此外,lincRNA-p21 促进体外和体内肝细胞凋亡,而 lincRNA-p21 抑制肝细胞的增殖率。肝细胞 lincRNA-p21 的多效性作用表明,它可能代表肝纤维化中的一个未知范例,并可作为治疗的潜在靶点。