脑脊液外泌体microRNA-133b促进大鼠脊髓损伤后神经血管再生作用机制研究

Acute spinal cord injury（SCI）has a high rate of disability and deformity with no effective treatmen util recentlyt. The destructive of neurovascular structure is the main cause of neurofunctional imparied. In our previous study, we found that the exosomes derived from cerebrospinal fluid has the potential role for promoting axon growth and vascular tube formation in vitro, with highly express of microRNA-133b by targeting reguation of the RhoA expression. However, the specific regulation mechanism of the exosomes on neurovascular regenration and neurological functional recovery after SCI is unkown. Therefore, this project intends to study the effects of exosome derived from cerebrospinal fluid on neurovascular regeneration and spinal neurological function recovery by using primary cortical neurons, vascular endothelial cells model in vitro and and SCI animal models in vivo. Next, we modify the expression pattern of exosomal microRNA-133b derived from the cerebrospinal fluid using the genetic engineering tools to elucidate that it is the key factor to regulate the neurovascular regeneration and the neurological functional recovery after SCI. We plan to use the target gene functional rescue experiment and specific signal inhibitor to further clarify the specific mechanism of exosomal microRNA-133b derived from cerebrospinal fluid on neurovascular regeneration by targeting inhibition of RhoA expression after SCI. This project may provide a new strategy for SCI treatment, also offer the preclinical experimental and theoretical basis for the treatment of SCI by using cerebrospinal fluid exosomes.

急性脊髓损伤（SCI）具有高致残、致畸率，目前无有效治疗手段。SCI导致的神经血管损伤是脊髓神经功能障碍的主要因素。申请人前期研究发现，SCI后脊髓脑脊液外泌体可以影响神经轴突生长和血管内皮细胞成管，经鉴定外泌体内microRNA-133b差异表达，并与RhoA存在靶向关系，有望成为新的SCI治疗手段，但具体调节作用机制不明。据此，本项目拟利用原代皮层神经元、脊髓微血管内皮细胞和SCI动物模型检测脊髓脑脊液外泌体对神经血管再生和脊髓神经功能恢复的影响；采用基因工程技术干扰外泌体中microRNA-133b表达，阐明其是调节脊髓神经血管再生和神经功能恢复的关键因子；利用靶基因功能回复和特异性抑制剂，深入揭示脊髓脑脊液外泌体microRNA-133b靶向抑制RhoA参与调节神经血管再生和神经功能恢复的分子网络机制。本项目将为SCI治疗提供新策略，并为脑脊液外泌体治疗SCI提供临床前的实验依据。

急性脊髓损伤（SCI）是一类严重的中枢神经系统创伤性疾病，神经血管单元（Neurovascular Unit, NVU）是由神经元与血管内皮细胞组成的结构功能单元，其结构的完整性对神经功能稳态维持至关重要。因此，促进NVU神经血管再生，是改善脊髓神经功能的关键靶点。.本项目“脑脊液外泌体microRNA-133b促进大鼠脊髓损伤后神经血管再生作用机制研究”基于体外血管/神经细胞模型及体内外泌体/神经血管单元模型，利用同步辐射三维成像技术、qPCR、WB实验等技术，从多个角度揭示脊髓损伤急性期脑脊液外泌体促进脊髓损伤后神经血管再生作用机制，并阐述其在SCI 中对神经血管再生的作用机理，为促进脊髓神经功能恢复，治疗SCI 提供实验基础和理论依据（J Orthop Transl接收）。.研究计划涉及的主要内容包括3个方面：1）提取并鉴定脊髓损伤急性期脑脊液外泌体；2）分析脊髓脑脊液外泌体对SCI 神经功能恢复和神经血管再生作用；3）揭示脑脊液外泌体通过PI3K/AKT通路促进SCI后神经血管再生的分子机制网络。