Department of Orthopedics, First Affiliated Hospital of Soochow University, Suzhou.
Department of Orthopedics, Zhangjiagang Hospital of Traditional Chinese Medicine, Jiangsu.
Rheumatology (Oxford). 2017 Oct 1;56(10):1804-1813. doi: 10.1093/rheumatology/kex233.
miRNAs are small, signal-strand, non-coding RNAs that function in post-transcriptional regulation. We analysed the in vivo effect of miR-106b (miR-106b-5p) on inflammatory bone loss in CIA mice.
CIA mice are developed by injecting DAB/1 mice with bovine type II collagen containing Freund's adjuvant and then the in vivo effect of miR-106b is examined. On day 22, mice were given lentiviral negative control, lentiviral-mediated miR-106b mimics or lentiviral-mediated miR-106b inhibitor via orbital injection on a weekly basis. Morphological changes in the ankle joints were assessed via micro-CT and histopathology and cytokine expression levels were examined via immunohistochemical staining, ELISA or flow cytometric analysis. miR-106b and osteoclastic-related gene expression was evaluated via quantitative real-time PCR.
CIA mice were found to have increased miR-106b expression and CIA-associated bone loss and inflammatory infiltration. miR-106b inhibitor treatment markedly decreased arthritis incidence and attenuated bone destruction and histological severity compared with the control group. Moreover, miR-106b inhibitor treatment suppressed RANK ligand (RANKL) expression, increased osteoprotegerin (OPG) expression and reduced the RANKL:OPG ratio in CIA mice. miR-106b inhibition also significantly decreased inflammatory mediator production in joint sections and reduced serum pro-inflammatory cytokine levels when compared with the control group. Additionally, miR-106b inhibition decreased tartrate-resistant acid phosphatase-positive cell numbers and suppressed murine bone marrow macrophage differentiation.
These findings indicate that miR-106b inhibition can ameliorate CIA-associated inflammation and bone destruction and thus may serve as a potential therapeutic for human RA treatment.
miRNAs 是一种小的、信号链、非编码 RNA，在转录后调节中发挥作用。我们分析了 miR-106b（miR-106b-5p）在 CIA 小鼠炎症性骨丢失中的体内作用。
通过向 DAB/1 小鼠注射含有福氏佐剂的牛 II 型胶原来建立 CIA 小鼠模型，然后检测 miR-106b 的体内作用。在第 22 天，通过眼眶注射每周向小鼠给予慢病毒阴性对照、慢病毒介导的 miR-106b 模拟物或慢病毒介导的 miR-106b 抑制剂。通过 micro-CT 和组织病理学评估踝关节的形态变化，通过免疫组织化学染色、ELISA 或流式细胞术分析检测细胞因子表达水平，通过定量实时 PCR 评估 miR-106b 和破骨细胞相关基因表达。
CIA 小鼠的 miR-106b 表达增加，与 CIA 相关的骨丢失和炎症浸润。与对照组相比，miR-106b 抑制剂治疗显著降低了关节炎的发生率，并减轻了骨破坏和组织学严重程度。此外，miR-106b 抑制剂治疗抑制了 RANK 配体（RANKL）的表达，增加了骨保护素（OPG）的表达，并降低了 CIA 小鼠中 RANKL:OPG 的比值。与对照组相比，miR-106b 抑制剂抑制也显著降低了关节切片中炎症介质的产生和血清促炎细胞因子水平。此外，miR-106b 抑制减少了抗酒石酸酸性磷酸酶阳性细胞的数量，并抑制了鼠骨髓巨噬细胞的分化。
这些发现表明，miR-106b 抑制可以改善 CIA 相关的炎症和骨破坏，因此可能成为治疗人类 RA 的潜在治疗方法。
