Huwe1调控proBDNF/p75NTR介导神经干细胞移植后GABA相关紧张性抑制对脑卒中后神经重塑的作用机制研究

Neural remodeling is the key to the functional recovery after stroke. Neural stem cells can secrete BDNF directly affect the neural remodeling after cerebral ischemia. But when NSC transplanted into body, the cell death rate is high, which lead to the lack of treatment effect. BDNF itself can feedback to improve the survival rate of transplanted stem cells, while a study shows that it is involved in the secretion of GABA inhibitory neurotransmitter. And GABA-mediated Itonic on cerebral ischemia after nerve remodeling is essential, and huwe1 regulate BDNF and p75NTR Combination can reduce nerve remodeling. ProBDNF is a precursor to BDNF, similar to proNGF, the affinity for p75NTR is higher than that of BDNF. In the stroke model group, huwe1 regulates proNGF / p75NTR in the cerebral ischemia model. Therefore, we suggest that huwe1 can also regulate the apoptosis of neural stem cells through proBDNF, further mediate GABA can Itonic, which affects post-stroke nerve remodeling. The mechanism of huwe1 and proBDNF / p75NTR after neural stem cell transplantation and neural remodeling after stroke were studied by using neural stem cell transplantation and magnetic resonance imaging.

神经重塑是影响脑卒中后功能恢复的关键。神经干细胞可分泌BDNF直接影响脑缺血后神经重塑，但其移植入体后，细胞死亡率高，无法达到治疗目的。BDNF可反馈提高移植干细胞的存活率，同时研究显示其参与抑制性递质GABA的分泌，而GABA介导的Itonic对脑缺血后神经重塑至关重要，且通过huwe1调控BDNF与p75NTR的结合可减低神经重塑。proBDNF作为BDNF的前体，与proNGF相似，对p75NTR的亲和力高于BDNF。课题组前期发现，在脑缺血模型中huwe1可调控proNGF/p75NTR参与神经重塑过程。因此我们推测huwe1也可通过proBDNF调控神经干细胞的凋亡，进一步介导GABA能Itonic，从而影响卒中后神经重塑。本课题拟利用神经干细胞移植及核磁共振技术，探讨huwe1与proBDNF／p75NTR在神经干细胞移植后凋亡及脑卒中后神经重塑的机制。

神经重塑是影响脑卒中后功能恢复的关键。神经干细胞可直接影响脑缺血后神经重塑，但其移植后细胞高死亡率限制了其应用，BDNF可反馈提高移植干细胞的存活率，参与抑制性递质GABA的分泌，对脑缺血后神经重塑至关重要。huwe1调控BDNF与p75NTR的结合可减低神经重塑，proBDNF作为BDNF的前体，与proNGF相似，对p75NTR的亲和力高于BDNF。课题组前期发现，在脑缺血模型中huwe1可调控proNGF/p75NTR参与神经重塑过程。因此我们推测huwe1也可通过proBDNF调控神经干细胞的凋亡，影响卒中后神经重塑。采用慢病毒敲低huwe1表达水平，在神经干细胞中检测干细胞迁移能力、BDNF和proBDNF表表达水平。使用立体定位注射技术敲低大鼠皮层huwe1表达水平，检测MCAO/R建模后神经行为学变化，使用WB、免疫荧光、免疫组化、golgi-cox染色评估神经重塑。在原代皮层神经元中敲低Huwe1后OGD/R通过WB检测proBDNF、p75NTR、gap-43、NF200变化情况，明确Huwe1调控神经重塑具体机制。结果显示，糖氧剥夺再灌注损伤后，敲低huwe1表达后对神经干细胞迁移能力的影响，证实敲低Huwe1可以促进神经干细胞BDNF表达，抑制proBDNF表达。敲低Huwe1可以改善大鼠MCAO/R后神经损伤恢复，促进神经重塑。敲低Huwe1可减少MCAO/R后proBDNF和p75NTR的表达，而这种神经保护作用被重组耐切割proBDNF所逆转。因此，本研究表明Huwe1的减少可以促进神经干细胞迁移能力，抑制神经干细胞中proBDNF的表达，促进脑缺血损伤后后功能恢复及神经重塑的功能，表明Huwe1是卒中的关键干预靶点。