NF-κB介导的巨噬细胞活化在关节粘连形成中的机制及干预研究

With a high occurrence rate, post-traumatic joint stiffness (PTJS), which would cause the physical disability, seriously influences patient's life quality. Effective drug is needed in clinical practice. In our previous research, blocking the downstream targets of TGF-β1 was found to be the mechanism of action of Celecoxib reducing the occurrence of articular adhesion, which provides inspiration to medication. TGF-β1, which comes mainly from macrophages, is regulated by NF-κB. As the adhesion formation is closely related to inflammation, macrophages promote inflammation through the expression of classical activation (M1) cytokines, but also activate the fibroblast activity through the alternative activation (M2) cytokines such as TGF-β1 resulting in adhesion. NF-κB may play a vital role in adhesion formation by regulating the expression of M1 and M2 cytokines. We hypothesize that NF-κB promotes adhesion formation by the regulation of M1 and M2 cytokines, thus drugs targeting at NF-κB may prevent adhesion. To verify the hypothesis, we will establish the joint adhesion model in macrophage-specific NF-κB knockout and overexpression mice and investigate the role of macrophage NF-κB in the pathogenesis of PTJS. Meanwhile, we would evaluate the efficacy of drug combination in the intervention of PTJS and provide theoretical basis for new strategies in the prevention and treatment of joint adhesion.

创伤后关节粘连发生率高，导致肢体活动障碍，严重影响患者的生活，临床治疗尚缺乏有效药物。本课题组前期研究发现：塞来昔布可干预转化生长因子β1 (TGF-β1)下游靶点，减轻关节粘连，为药物治疗提供了重要思路。巨噬细胞（Mφ）在炎症时产生TGF-β1，其表达受NF-κB控制。粘连的发生与炎症关系密切，Mφ通过经典活化（M1）后产生相关因子促进炎症，还通过替代性活化（M2）分泌TGF-β1刺激成纤维细胞导致粘连。NF-κB调控Mφ M1和M2型因子的表达，在粘连中有可能发挥重要作用。本课题假设NF-κB通过控制M1、M2型因子的表达参与关节粘连，是药物治疗的潜在靶点。为验证该假说，本课题拟利用Mφ特异性NF-κB敲除及过表达小鼠，建立关节粘连模型，通过与野生型小鼠比较，验证Mφ NF-κB在粘连形成过程中的作用及机制，考察药物抑制NF-κB靶点的疗效，为防治关节粘连提供新的理论依据与策略。

肌腱粘连严重影响患肢功能，是手外科中一项棘手的问题，己知巨噬细胞以及转录因子NF-KB RelA/p65在诸多纤维化疾病中发挥重要作用，但其在肌腱粘连形成中的作用及潜在机制未知。本课题通过检测人来源肌腱粘连组织中基因表达差异、p65和细胞外基质的表达情况，结合大鼠肌腱损伤模型中p65与肌腱粘连的关系。通过小干扰RNA（siRNA）抑制p65，从体内考察p65抑制对肌腱粘连形成的影响，并在体外实验中成纤维细胞中分别通过p65siRNA抑制p65，探明p65对粘连形成的影响及机制。另外，通过对比野生型小鼠和巨噬细胞缺失小鼠（药物构建）中肌腱术后的粘连程度，阐明了巨噬细胞在肌腱粘连形成中的作用。本课题为肌腱粘连的防治提供了新思路和新靶标。