Zhu Feng, Li Huarong, Liu Yujin, Tan Chen, Liu Xingxing, Fan Heng, Wu Hui, Dong Yalan, Yu Ting, Chu Si, He Hongxia, Zhu Xiwen
Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
Department of Integrated Traditional Chinese and Western Medicine, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
Biomed Pharmacother. 2020 Jun;126:109909. doi: 10.1016/j.biopha.2020.109909. Epub 2020 Mar 2.
Th subsets particularly T helper 17 and regulatory T cells play a critical role in immune balance in colonic mucosa of Inflammatory Bowel Disease. Recent studies have indicated miR-155 is overexpressed in the colonic mucosa in IBD patients. Thus, whether and how miR-155 influences Th17/Treg cell balance in IBD patients is worthy of researching.
We divided mice into four groups: the mice oral administration of 3.0 % DSS in fresh drinking water for 7 days except normal group. In this period, starting from the fifth day, the miR-155 and NC antagomir group were carried out by intraperitoneal injection of miR-155 antagomirs and corresponding negative controls. In vitro, we isolated naïve CD4T cells and divided into two groups: the cells were transfected with mmu-miR-155-5p inhibitor or corresponding negative controls and then induced differentiation.
We found miR-155 antagomir can reach colon tissues in DSS-induced colitis and indeed ameliorated DSS-induced experimental colitis. Subsequently, we proved the levels of Th17 cells in spleens and Mesenteric lymph nodes and its associated IL-6, IL-17A and RORγt in colonic tissues were dramatically decreased and TGF-β1 raised in DSS + miR-155 antagomir group. However, miR-155 antagomir significantly increased the expression of Tregs. In vitro, we found miR-155 inhibitor could improve the Tregs but decrease Th17 cells. Finally, we dig out that Jarid2 was apparently improved by miR-155 antagomir, Wnt/β-catenin and its associated T cell factor-4 (TCF-4) and Cyclin D1 expression were positively correlated with Jarid2.
Silencing of miR-155 attenuates DSS-induced colitis by regulating Th17/Treg cell balance and Jarid2/Wnt/β-catenin participated in the process.
Th 亚群尤其是辅助性 T 细胞 17 和调节性 T 细胞在炎症性肠病结肠黏膜的免疫平衡中起关键作用。最近的研究表明，miR-155 在炎症性肠病患者的结肠黏膜中过度表达。因此，miR-155 是否以及如何影响炎症性肠病患者的 Th17/Treg 细胞平衡值得研究。
我们将小鼠分为四组：除正常组外，其余小鼠在新鲜饮用水中口服 3.0%的葡聚糖硫酸钠（DSS）7 天。在此期间，从第 5 天开始，miR-155 和阴性对照拮抗剂组通过腹腔注射 miR-155 拮抗剂和相应的阴性对照进行处理。在体外，我们分离出初始 CD4T 细胞并分为两组：细胞转染 mmu-miR-155-5p 抑制剂或相应的阴性对照，然后诱导分化。
我们发现 miR-155 拮抗剂可以到达葡聚糖硫酸钠诱导的结肠炎小鼠的结肠组织，并确实改善了葡聚糖硫酸钠诱导的实验性结肠炎。随后，我们证明了在 DSS + miR-155 拮抗剂组中，脾脏和肠系膜淋巴结中的 Th17 细胞水平及其在结肠组织中相关的白细胞介素-6、白细胞介素-17A 和维甲酸相关孤儿受体γt 显著降低，而转化生长因子-β1 升高。然而，miR-155 拮抗剂显著增加了调节性 T 细胞的表达。在体外，我们发现 miR-155 抑制剂可以增加调节性 T 细胞但减少 Th17 细胞。最后，我们发现 miR-155 拮抗剂明显上调了 Jarid2，Wnt/β-连环蛋白及其相关的 T 细胞因子-4（TCF-4）和细胞周期蛋白 D1 的表达与 Jarid2 呈正相关。
miR-155 的沉默通过调节 Th17/Treg 细胞平衡减轻葡聚糖硫酸钠诱导的结肠炎，且 Jarid2/Wnt/β-连环蛋白参与了这一过程。
