Celsr2促进周围神经再生的分子机制研究

Previous studies demonstrated that etifoxine can promote peripheral nerve regeneration (published article), However there is some side effect of etifoxine. Thus finding new molecular therapeutic targets is very important. Further study found that etifoxine could increase the expression of a transmembrane glycoprotein Celsr2 which is important in nervous system development and maintenance. However, whether Celsr2 play an important role in peripheral nerve regeneration and its detailed molecular mechanisms is still unknown. In preliminary experiments we found Celsr2 promote PC12 cell growth and proliferation of Schwann cell. Spectrum analysis further found that in high expression of Celsr2 cells, wnt / β-catenin signaling pathway is activated most significantly, and we found Celsr2 could bind with Axin and LRP6. On this basis, we will examine whether Celsr2 promote the axon growth of DRG, and sciatic nerve regeneration. Also, using immunofluorescence，Immune protein co-precipitation and other methods, we try to determine whether Celsr2 could activates wnt / β catenin signaling pathway through Celsr2 / Axin / LRP6 complex and finally peripheral nerve regeneration.

我们前期研究证明药物依替福嗪 (etifoxine)可促进周围神经再生（已发表）,但其临床应用存在一定不良反应。因此寻找新的分子治疗靶点具有重要意义。进一步发现etifoxine可诱导与神经系统发育及维持相关的膜蛋白Celsr2表达。然而，Celsr2是否在周围神经再生中发挥作用及其机制仍未知。在预实验中，我们发现Celsr2具有促进PC12细胞及施旺细胞生长的功能。进一步RNA表达谱分析结果显示Celsr2与 wnt/β-catenin信号通路相关，我们初步发现Celsr2与Axin及LRP6结合。在此基础上，本项目将深入研究Celsr2是否促进背根神经元轴突生长及在大鼠体内促进坐骨神经修复，进一步探讨Celsr2在周围神经再生中的作用，并通过免疫蛋白共沉淀法、免疫荧光法等证明Celsr2通过Celsr2/Axin/LRP6复合物激活wnt/β-catenin通路促进周围神经再生的新假说

研究周围神经再生及其分子机制对寻找新的治疗靶点及开发新型药物具有重要意义。我们阐明了Celsr2促进PC12 细胞胞轴突生长和胞体增大，诱导施旺细胞增殖，背根神经节生长及小鼠体内坐骨神经损伤后再生。Celsr2与Axin、LRP6结合，在Celsr2与Axin、LRP6形成的复合物中Celsr2提高了LRP6的磷酸化水平，激活wnt/β-catenin，从而促进周围神经再生，可作为周围神经再生潜在的分子治疗靶点。另外，我们构建了micro-CT坐骨神经巨微解剖结构模型，用于周围神经再生的评价及诊断（已发表于Int J Clin Exp Med）；以往研究表明淋巴水肿与神经再生密切相关，研究VEGFR与其之间相关性发现VEGFR与家族性淋巴水肿显著相关，同时该家族中神经再生能力也降低（已发表于International Journal of medical research）；NF-κB信号通路在周围神经损伤后再生过程中发挥重要作用，我们的研究揭示了与Celsr2结合蛋白TRIM37，作为E3连接酶，促进TRAF2 K63位泛素化，持续性激活NF-κB信号通路（已发表于The journal of pathology）。这一系列研究不仅为周围神经研究增添了新的内容，还为开发有效的周围神经再生分子靶向药物提供新的线索，为寻找治疗周围神经再生提供直接的科学依据。