抑制自噬减少大鼠脊髓损伤后髓鞘碱性蛋白的丢失  

Inhibition of Autophagy Decreases the Loss of Myelin Basic Protein in Rats after Spinal Cord Injury

作　　者：杨德刚[1] 李建军[1] 杨明亮[1] 杜良杰[1] 褚宏宇[1] 胡安明[2] 高峰[1] 李军[1] 顾蕊[3] 

机构地区：[1]首都医科大学康复医学院中国康复研究中心脊柱脊髓神经功能重建科,北京100068 [2]首都医科大学康复医学院中国康复研究中心脑外科,北京100068 [3]首都医科大学康复医学院中国康复研究中心骨科,北京100068

出　　处：《神经损伤与功能重建》2015年第3期194-197,共4页Neural Injury and Functional Reconstruction

基　　金：国家自然科学基金(No.81272164);中国康复研究中心课题(No.2011-23)

摘　　要：目的:观察自噬抑制剂对脊髓损伤后髓鞘碱性蛋白(MBP)表达的影响。方法:将99只大鼠随机分成假手术组、损伤组和干预组各33只,各组再分成损伤后3、7、14 d 3个时间点,应用打击器制备T10脊髓损伤模型。干预组造模前注射1μL 3-甲基腺嘌呤(3-MA)。假手术组不造成打击。提取脊髓样本进行Western blot和实时定量荧光PCR检测自噬相关蛋白LC3-Ⅱ和MBP的蛋白、m RNA水平。用BBB行为学评分分别于伤后1、7、14 d评估大鼠。结果:伤后14 d时干预组的BBB评分明显高于损伤组(P=0.001)。损伤组各时间点大鼠脊髓损伤区域的LC3-Ⅱ蛋白含量较假手术组明显增加(P<0.05),干预组损伤区域的LC3-Ⅱm RNA和蛋白水平在伤后3、7、14 d均比损伤组减少(P<0.05)。干预组大鼠损伤区域的MBP m RNA和蛋白水平在伤后3、7、14 d均比损伤组增加(P<0.05)。结论:大鼠脊髓损伤后存在自噬的过度激活,自噬抑制剂可通过减少脊髓损伤后MBP的丢失发挥神经保护作用。Objective：To investigate the effects of autophagic inhibitors on the expression of myelin basic protein（MBP） after spinal cord injury（SCI） in rats. Methods： Ninety-nine rats were randomly assigned to groups of sham-operated, SCI and treatment. The T10 SCI contusion model was induced with an impactor. One μL 3-Methyladenine was slowly injected into spinal cord immediately before the contusion in the treatment group. The protein or m RNA expression of LC3-Ⅱ and MBP were detected by Western-blot or real-time quantitative reverse transcriptase polymerase chain reaction（RT-PCR） respectively. Functional recovery（BBB scores） was evaluated at 1st, 7th,14 th day post-injury. Results： The BBB score of the treatment group was higher than that in the SCI group（P=0.001） at 14 th day post-injury. The protein content of LC3-II within the spinal lesion in the SCI group was significantly higher than that in the sham-operated group（P〈 0.05）, while the protein or m RNA level of LC3-II in the treatment group was lower than those in the SCI group（P〈0.05）. The protein or m RNA level of MBP in the treatment group at 3th, 7th, or 14 th days post-injury were higher than those in the SCI group（P〈0.05）. Conclusion：There was overactive autophagy in spinal cord lesion after SCI in rats. The inhibitor of autophagy could protect the nervous system via decreasing the loss of MBP in rats after SCI.

关 键 词：脊髓损伤 髓鞘碱性蛋白 自噬 LC3-Ⅱ 3-甲基腺嘌呤 

分 类 号：R741[医药卫生—神经病学与精神病学] R744[医药卫生—临床医学]