OPN/IGF1促进小鼠皮质脊髓束轴突再生的作用及机制研究  

OPN/IGF1 promotes the corticospinal tract regeneration by increasing neuron IGFR expression

作　　者：张倩[1] 张坤 张增强[1] 李剑勇 崔芳[1] Zhang Qian;Zhang Kun;Zhang Zeng-Qiang;Li Jian-Yong;Cui Fang(Department of Neurology,Hainan Hospital of Chinese PLA General Hospital,Sanya,Hainan 572013,China;Department of Neurobiology,Air Force Military Medical University,Xi'an 710032,China)

机构地区：[1]解放军总医院海南医院神经内科,海南三亚572013 [2]空军军医大学神经生物学教研室,西安710032

出　　处：《解放军医学杂志》2021年第10期955-960,共6页Medical Journal of Chinese People's Liberation Army

基　　金：国家自然科学基金(81901252,81601056);海南省自然科学基金(820QN383,2018CXTD348)。

摘　　要：目的研究骨桥蛋白(OPN)/胰岛素样生长因子1(IGF1)在小鼠皮质脊髓束(CST)再生中的作用及相关分子机制。方法 6~8周龄C57BL/6小鼠28只,随机分为实验组与对照组,每组14只。建立小鼠单侧锥体束横断模型,实验组在损伤对侧皮质注射腺相关病毒(AAV)-OPN/IGF1,对照组在损伤对侧皮质注射AAV-胎盘碱性磷酸酶(PLAP)。术后每2周采用行为学方法评估小鼠运动功能的恢复情况。术后12周处死小鼠,采用脊髓蛋白激酶Cγ(PKCγ)免疫组化染色判断皮质脊髓束横断情况;采用红色荧光蛋白(RFP)免疫组化染色分析轴突发芽的情况;采用免疫荧光染色检测神经元OPN和IGF1相关信号通路中核糖体蛋白S6激酶(pS6)和胰岛素样生长因子受体(IGFR)表达情况,研究OPN/IGF1促进轴突发芽的分子机制。结果通过采用PKCγ免疫组化染色判断皮质脊髓束残余情况,最终实验组入组小鼠10只,对照组入组小鼠8只。实验组与对照组相比,OPN/IGF1对小鼠运动功能恢复无明显作用;皮质神经元高表达OPN/IGF1以后,损伤对侧皮质脊髓束发芽增多,神经元pS6和IGFR表达均明显高于对照组,差异有统计学意义(P<0.05)。结论 OPN/IGF1可通过增加神经元IGFR和pS6表达而促进CST发芽。Objectives To study the role and associated potential molecular mechanism of osteopontin/insulin-like growth factor 1 (OPN/IGF1) in the corticospinal tract (CST) regeneration.Methods A total of 28 adult C57BL/6 mice (6-8 weeks old) were randomized into the experimental group (injection of AAV-OPN/IGF1,;=14) and control group (injection of AAV-PLAP,;=14) after training of single pellet retrieval.After received the unilateral pyramidotomy surgery,animals received AAV-OPN/IGF1 or AAV-PLAP at the injury site.Further,we employed the movement behaviour test to evaluate spinal motor recovery at 2-week intervals till 12-week after surgery.The protein kinase Cγ (PKCγ) staining in the dorsal funiculus of the cervical spinal cord indicated surgical efficiency.Lastly,we examined the axon sprouting and expression levels of ribosomal protein S6 kinase (pS6) and insulin-like growth factor receptor (IGFR) in neurons using immunohistochemical staining to study the potential mechanism of OPN/IGF1 to promote axon prouting.Results After evaluating PKCγ staining to indicate surgery effectiveness,a total of ten mice were in the experimental group and eight in the control group.In the mouse unilateral pyramidotomy model,OPN/IGF1 has not much effect on the recovery of motor function compared with the control group.After the overexpression of OPN/IGF1 on cortical neurons,sprouting of the spared CST was increased by the elevated expression of pS6 and IGFR,and the difference was statistically significant (;<0.05).Conclusions OPN/IGF1 promotes the sprouting of the CST by increasing the expression of neuronal IGFR and pS6.

关 键 词：骨桥蛋白/胰岛素样生长因子1 锥体束横断术 轴突再生 胰岛素样生长因子受体 

分 类 号：R744[医药卫生—神经病学与精神病学]