Lu Zhan-Jun, Wu Jian-Jiong, Jiang Wei-Liang, Xiao Jun-Hua, Tao Kai-Zhong, Ma Lei, Zheng Ping, Wan Rong, Wang Xing-Peng
Zhan-Jun Lu, Jian-Jiong Wu, Wei-Liang Jiang, Kai-Zhong Tao, Lei Ma, Rong Wan, Xing-Peng Wang, Department of Gastroenterology, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200080, China.
World J Gastroenterol. 2017 Feb 14;23(6):976-985. doi: 10.3748/wjg.v23.i6.976.
To explore the mechanism by which microRNA-155 (miR-155) regulates the pathogenesis of experimental colitis.
A luciferase assay was performed to confirm the binding of miR-155 to the SHIP-1 3'-UTR. MiR-155 mimics, negative controls and SHIP-1 expression/knockdown vectors were established and then utilized in gain- and loss-of-function studies performed in raw264.7 cells and primary bone marrow-derived macrophages (BMDMs). Thereafter, dextran sulfate sodium (DSS)-induced colitis mouse model with or without antagomiR-155 treatment was established, and the levels of miR-155 and SHIP-1, as well as the pro-inflammatory capabilities, were measured by western blot, quantitative polymerase chain reaction, and immunohistochemistry.
MiR-155 directly bound to the 3'-UTR of mRNA and induced a significant decrease in SHIP-1 expression in both raw264.7 cells and primary BMDMs. MiR-155 markedly promoted cell proliferation and pro-inflammatory secretions including IL-6, TNF-α, IL-1β, and IFN-γ, whereas these effects could be reversed by the restoration of SHIP-1 expression. studies showed that antagomiR-155 administration could alleviate DSS-induced intestinal inflammation in Balb/c mice. Moreover, significantly increased SHIP-1 expression, as well as decreased Akt activation and inflammatory response, were observed in the antagomiR-155-treated mice.
MiR-155 promotes experimental colitis by repressing SHIP-1 expression. Thus, the inhibition of miR-155 might be a promising strategy for therapy.
探讨微小RNA-155（miR-155）调控实验性结肠炎发病机制的作用机制。
进行荧光素酶报告基因检测以证实miR-155与SHIP-1 3'-非翻译区（3'-UTR）的结合。构建miR-155模拟物、阴性对照以及SHIP-1表达/敲低载体，随后用于在raw264.7细胞和原代骨髓来源巨噬细胞（BMDM）中进行的功能获得和功能丧失研究。此后，建立了接受或未接受抗miR-155治疗的葡聚糖硫酸钠（DSS）诱导的结肠炎小鼠模型，并通过蛋白质免疫印迹法、定量聚合酶链反应和免疫组织化学检测miR-155和SHIP-1的水平以及促炎能力。
miR-155直接与mRNA的3'-UTR结合，并导致raw264.7细胞和原代BMDM中SHIP-1表达显著降低。miR-155显著促进细胞增殖和促炎分泌物，包括白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、白细胞介素-1β（IL-1β）和干扰素-γ（IFN-γ），而SHIP-1表达的恢复可逆转这些作用。研究表明，给予抗miR-155可减轻Balb/c小鼠中DSS诱导的肠道炎症。此外，在接受抗miR-155治疗的小鼠中观察到SHIP-1表达显著增加，以及Akt激活和炎症反应降低。
miR-155通过抑制SHIP-1表达促进实验性结肠炎。因此，抑制miR-155可能是一种有前景的治疗策略。
