miR-26a调节GSK-3β和LINGO-1调控NSCs凋亡和分化治疗心脏骤停后脑损伤的作用和机制

The whole cerebral hypoxic-ischemia injury is the key to success for cardiopulmonary cerebral resuscitation after cardiac arrest, neural stem cells(NSCs) therapy is the research hot spot to improve and promote the cranial neuronal differentiation. But no matter endogenous NSCs activation or extrinsic NSCs transplantation treatment is still not ideal, one is because of the number of NSCs apoptosis and dwindling, another is NSCs natural differentiated into neurons ratio is very low. Our initial study found that miR-26a can inhibit apoptosis in vitro culture of NSCs, prompting them to neurons direction differentiation; And through the bioinformatics analysis found that GSK-3β and LINGO-1 is the two control targets of miR-26a. Therefore, we propose two hypothesis: miR-26a targeted GSK-3β to activate the path of WNT/β-catenin, and inhibit apoptosis of NSCs; miR-26a targeted LINGO-1 to prevent myelin sheath from inhibiting protein role, and make NSCs differentiate into neurons. Through this research, we can reveal the role and molecular mechanism of miR-26a in NSCs apoptosis and differentiation, and provide new scientific theory in it for the first time, and provide new goals and targets of drug research and development for NSCs apoptosis inhibition and directional differentiation.

心脏骤停后的全脑缺血缺氧性损伤是心肺脑复苏成败的关键，干细胞治疗是改善及促进脑神经元分化研究的热点。但无论内源性NSCs活化还是外源性NSCs移植治疗仍不理想，一是NSCs 因为凋亡而数量不断减少，二是NSCs 自然分化为神经元的比率很低。我们前期研究发现miR-26a 能抑制体外培养的NSCs凋亡，促使其向神经元方向分化；且通过生物信息学分析发现GSK-3β和LINGO-1是miR-26a的两个调控靶点。因此，我们提出两个假说：miR-26a靶向GSK-3β激活WNT/β-catenin通路，抑制NSCs的凋亡；miR-26a靶向LINGO-1拮抗髓鞘抑制蛋白的作用，而促使NSCs分化为神经元。通过本研究，可首次揭示miR-26a在NSCs 凋亡和分化中的作用及分子机制，为NSCs凋亡和分化提供新的科学理论，并为NSCs 凋亡抑制和定向分化的药物研发提供新的目标和靶点。

在急诊医学重点研究的领域中，由心脏骤停(Cardiac Arrest, CA)所致全脑和心肌的缺血缺氧性损伤最常见，且随着社会老龄化的到来将更趋严重，是目前迫切需要解决的医疗问题之一。本课题组从神经干细胞对脑保护作用入手，以氯化钴作为体外实验缺血缺氧模型，以窒息和电击致颤为体内心脏骤停模型，以大鼠和猪作为实验用动物，先后主要研究了以下几个内容：1、低氧诱导神经干细胞凋亡和miR-26a低表达；2、miR-26a抑制低氧条件下神经干细胞凋亡；3、miR-26a通过GSK-3β抑制神经干细胞凋亡；4、miR-26a抑制神经干细胞凋亡对心脏骤停大鼠的脑保护作用；5、窒息性CA/CPR对大鼠心脑功能的影响；6、七氟醚对心脏骤停大鼠脑保护的实验研究；7、七氟醚减轻心脏骤停大鼠脑MPTP开放及机制研究；8、猪室颤CA模型的建立及腹腔诱导亚低温的实验研究。通过以上研究，本课题组不仅从细胞分子学的层面探讨了心肺复苏的心脑损伤问题，而且还将研究延伸到了大动物猪的层面，为今后更好的贴近临床转化和进一步研究打下了基础。本课题组还以此课题的部分研究成果作为研究基础，成果申请并获批了下一个国自然面上项目《HIF-1α和NSCs联合移植通过外泌体转移microRNA促进NSCs存活和增殖治疗心脏骤停后脑损伤》。依靠本课题基金的支持先后培养了5名博士和3名硕士。