脊髓损伤分子病理机制及雪旺细胞联合骨髓间充质干细胞干预修复的研究

Spinal cord injury（SCI）is severe disease with high morbidity and high rate of disability. Because of the unknown pathological mechanisms, little progress has been made to the management of SCI. Our group has a long standing interest in the recovery of SCI based on the cell transplantation. Our previous research has shown that activated schwann cells (ASCs) not only can secrete neurotrophic factors to restrict the apoptosis of the neurons, but also induce bone mesenchymal stem cells（BMSCs）differentiate into neural cell which can promote axonal regeneration and functional recovery. However, the underlying mechanisms of activation and induction are still unclear. In this project, we plan to establish the animal model of SCI，and the changes of miRNA and key proteins after SCI will be examined through the technologies such as microarray and iTRAQ proteomics. The molecular mechanism of SCI will please be specific on this statement. Additionally, the mechanisms of ASCs self-activation and the regulation of the neural differentiation will be revealed. According to the pathological features of injury, the efficacy and repair mechanism of co-transplantation autologous ASCs and BMSCs in different time periods after SCI will be further investigated and defined. The goals of the project are to identify the targets and cell signaling pathways of SCI, and to establish a more reliable and effective treatment strategy of cell transplantation. The outcome of this proposal will shed light on fundamental problems confounding stem cell therapies and pave the way for the further research of spinal cord injury and improving early rehabilitation and efficacy of treatments.

脊髓损伤（SCI）发病率高、致残率高。其病理机制研究不清导致治疗困难。申请人团队长期致力于细胞移植修复脊髓损伤的研究，发现自体激活雪旺细胞（ASCs）不仅能分泌神经营养因子，抑制神经元凋亡，还可以诱导骨髓间充质干细胞（BMSCs）向神经元方向分化，促进轴突再生和功能恢复。但具体的激活及诱导机制尚不清楚。本研究拟建立脊髓损伤动物模型，通过microarray和iTRAQ蛋白质组学技术观察损伤前后miRNA和关键蛋白变化，探讨脊髓损伤的分子病理机制；揭示ASCs自我激活及诱导BMSCs向神经元方向分化的内在规律；根据损伤分子病理特点，分析不同时期自体ASCs联合BMSCs移植修复脊髓损伤的疗效及作用机理，明确脊髓损伤相关靶点及细胞信号通路，寻求建立更加可靠有效的细胞移植策略。同时自体移植避免伦理问题和免疫排斥反应，有利于突破我国干细胞领域的重大瓶颈，为实现脊髓损伤的有效修复和早期康复创造条件。

脊髓损伤（SCI）发病率高、致残率高。其病理机制研究不清导致治疗困难。申请人团队长期致力于细胞移植修复脊髓损伤的研究，发现自体激活雪旺细胞（ASCs）不仅能分泌神经营养因子，抑制神经元凋亡，还可以诱导骨髓间充质干细胞（BMSCs）向神经元方向分化，促进轴突再生和功能恢复。但具体的激活及诱导机制尚不清楚。本研究建立脊髓损伤动物模型，通过microarray和iTRAQ蛋白质组学技术观察损伤前后miRNA和关键蛋白变化，建立脊髓损伤后转录组学和蛋白质组学数据库，确定多个分子共表达网络。课题组通过对比SCI前后转录组学数据库，针对多个潜在调控SCI后神经再生miRNA进行验证，并开发相应拮抗物进行模拟干预修复SCI，利用蛋白质组学数据库，结合RNAi技术抑制关键调控分子，改善脊髓损伤微环境，为SCI的修复提供了大量新的修复方法，为临床药物的开发提供了新思路；课题组使用Microarray及iTRAQ技术对不同时期自体激活雪旺细胞的基因表达谱进行分析，发现诱导激活后不同时间，基因组表达变化趋势，并在表观遗传学方面发现DNA甲基化与雪旺细胞激活密切相关，并使用小分子诱导剂激活雪旺细胞，模拟体内激活过程；课题组应用Microarray及iTRAQ蛋白质组学技术观察转录和翻译调控层面的变化情况，双向寻找细胞行为活性的关键信号通路及调控位点，揭示ASCs、SCs诱导BMSCs向神经元方向分化的机制；课题组利用转录组和蛋白质组学技术，对联合移植ASCs及BMSCs修复SCI机制进行分析，揭示不同时期联合移植ASCs及BMSCs修复SCI的分子特点和信号调控网络，明确SCI复杂的内源性修复过程中的关键因子与信号通路，形成完整的脊髓损伤的“损伤-修复”体系。并针对内源性神经干细胞激活，开发联合小分子诱导神经干细胞向神经元方向分化方法，实现脊髓损伤微环境再平衡。课题组在脊髓损伤微环境机制研究基础上，开发针对微环境分子网络药物，进一步优化干细胞修复脊髓损伤效果，增加临床应用前景。该研究成果，有利于突破我国干细胞领域的重大瓶颈，为实现脊髓损伤的有效修复和早期康复创造条件。