Department of Cardiovascular Surgery, First Affiliated Hospital of Anhui Medical University, No.218 Ji-Xi Road, Hefei 230022, China.
Biosci Rep. 2019 Nov 29;39(11). doi: 10.1042/BSR20192215.
The aim of the present study was to explore the role of long non-coding RNA (lncRNA) non-coding repressor of NFAT (NRON) in the atrial fibrosis and to explore whether its underlying mechanism was associated with macrophage polarization. Enzyme-linked immunosorbent assay (ELISA) analysis of pro-inflammatory cytokines revealed that NRON overexpression suppressed, whereas NRON silencing facilitated the angiotensin II (Ang II)-induced inflammatory response in primary cultured atrial myocytes. The chromatin immunoprecipitation (ChIP) results showed that nuclear factor of activated T cell 3 (NFATc3) was recruited to the promoter region of interleukin (IL) 12 (IL-12) in atrial myocytes. Further data showed that NRON overexpression suppressed, whereas NRON silencing further promoted the Ang II-induced NFATc3 nuclear transport and IL-12 expression in atrial myocytes. Moreover, RAW264.7 macrophages were incubated with the conditioned medium from the Ang II-treated atrial myocytes transfected with NRON and IL-12 overexpression vectors. IL-12 overexpression abrogated the NRON overexpression-mediated inhibition of RAW264.7 macrophage polarization to the M1-like phenotype. Additionally, mouse atrial fibroblasts were incubated with the culture medium from RAW264.7 macrophages treated as described above. IL-12 overexpression rescued the NRON overexpression-inhibited protein levels of fibrosis markers Collagen I/III in mouse atrial fibroblasts. Collectively, our data indicate that lncRNA NRON alleviates atrial fibrosis through suppression of M1 macrophages activated by atrial myocytes.
本研究旨在探讨长链非编码 RNA（lncRNA）非 NFAT 抑制因子（NRON）在心房纤维化中的作用，并探讨其潜在机制是否与巨噬细胞极化有关。酶联免疫吸附试验（ELISA）分析促炎细胞因子显示，NRON 过表达抑制，而 NRON 沉默促进原代培养的心房肌细胞中血管紧张素 II（Ang II）诱导的炎症反应。染色质免疫沉淀（ChIP）结果显示，激活 T 细胞核因子 3（NFATc3）被募集到心房肌细胞中白细胞介素（IL）12（IL-12）启动子区域。进一步的数据表明，NRON 过表达抑制，而 NRON 沉默进一步促进 Ang II 诱导的 NFATc3 核转运和心房肌细胞中 IL-12 的表达。此外，用转染了 NRON 和 IL-12 过表达载体的 Ang II 处理的心房肌细胞的条件培养基孵育 RAW264.7 巨噬细胞。IL-12 过表达消除了 NRON 过表达介导的对 RAW264.7 巨噬细胞向 M1 样表型极化的抑制作用。此外，用如上所述处理的 RAW264.7 巨噬细胞的培养基孵育小鼠心房成纤维细胞。IL-12 过表达挽救了 NRON 过表达抑制的小鼠心房成纤维细胞中纤维化标志物 Collagen I/III 的蛋白水平。综上所述，我们的数据表明，lncRNA NRON 通过抑制心房肌细胞激活的 M1 巨噬细胞缓解心房纤维化。
