摘要
目的探讨SS31肽对脊髓损伤后自噬的影响及其可能机制。方法采用Allen法制做脊髓损伤动物模型。将90只sD大鼠按随机数字表法分为假手术组、脊髓损伤组、SS31肽处理组，每组30只。假手术组只行椎板切除术，不造成脊髓损伤；脊髓损伤组按Allen法制做脊髓损伤模型，不进行干预处理；SS31肽处理组按Allen法造成脊髓损伤后给予SS31肽干预处理。伤后6h、1，3，7，14d对各组大鼠进行BBB运动功能评分，并检测各组大鼠自噬相关基因6（Beclin-1）、微管相关蛋白1轻链3（LC3）-Ⅱ的变化。结果伤后6h、1，3，7，14dBBB运动功能评分，脊髓损伤组（0、1．7±0．4、3．5±0．6、6．1±0．7、10．1±0．6）和SS31肽处理组（0、2．5±0．7、4．1±0．7、9．3±0．6、13．4±0．6）与假手术组（各时点均为21）比较均降低（P〈0．05）；伤后7，14dSS31肽处理组BBB评分与脊髓损伤组比较升高（P〈0．05）；伤后6h、1，3dSS31肽处理组BBB评分与脊髓损伤组比较，差异无统计学意义（P〉0．05）。与假手术组比较，脊髓损伤组和SS31肽处理组Beclin-1表达均上升，3d（1．478±0．030、1．841±0．051）达到高峰，7d（1．302±0．049、1．551±0．032）仍升高，14d（1．252±0．048、1．47l±0．062）仍有高表达（P〈0．05）。与假手术组比较，脊髓损伤组和SS31肽处理组LC3-Ⅱ表达也上升，3d（0．348±0．028、0．655±0．052）达到高峰，7d（0．301±0．053、0．432±0．052）仍升高，14d（0．268±0．049、0．371±0．052）也有高表达（P〈0．05）；伤后3dSS31肽处理组Beclin-1、LC3-Ⅱ表达量较脊髓损伤组升高（P〈0．05）；伤后6h、1，7，14dSS31肽处理组Beclin-1和LC3-Ⅱ表达量与脊髓损伤组比较，差异无统计学意义（P〉0．05）。结论SS31肽能够提高大鼠脊髓损伤后的运动功能，增强神经细胞自噬，此可能是SS31肽治疗脊髓损伤的机制之一。
Objective To explore the effect of SS31 peptide on autophagy after spinal cord injury （SCI） and possible mechanism. Methods Allen method was used to construct the spinal cord injury model in rats. Sprague-Dawley rats were randomly divided into sham surgery group （sham group） , SCI group and SS31 peptide group, with 30 rats in each group. The sham group only received laminectomy. The rats in SCI group were sustained SCI and were given no intervention. The rats in SS31 group received SS31 peptide injection after SCI. Scores of Basso Beattie Bresnahan （BBB） motor functions were assessed at 6 h, 1, 3, 7 and 14 d after the injury. The changes in related proteins of Beclin-1 and LC3-Ⅱ were also detected. Results Scores of BBB scale at 6 h and at days 1,3,7 and 14 after injury in SCI group （0, 1.7±0.4, 3.5±0.6, 6.1 ±0.7, 10.1±0.6） andSS31 peptidegroup （0, 2.5±0.7,4. 1±0.7,9.3 ± 0.6, 13.4 ± 0.6） were lower than that in sham group （21 at all time points） （P 〈 0.05 ）. Scores of BBB scale at days 7 and 14 after injury in SS31 peptide group （9.3±0.6, 13.4±0.6） was higher than that in SCI group （6.1 ±0.7, 10.1 ±0.6） （P 〈0.05）. There was no significant difference upon scores of BBB scale of SS31 peptide group at 6 h and at days 1 and 3 after injury （0, 2.5 ±0.7, 4.1± 0.7）, compared with SCI group （0, 1.7 ± 0.4, 3.5 ± 0.6） （P 〉 0.05）. Compared with sham group, the expression of Beclin-1 in SCI group and SS31 peptide group was increased, reached a peak at day 3 （ 1. 478 ±0. 030, 1. 841± 0. 051 ）, remained high level at day 7 （ 1. 302± 0. 049, 1.551 ±0. 032） and showed high expression at day 14 （1. 252 ±0.048, 1. 471 ecO. 062） （P 〈0. 05）. Compared with sham group, the expression of LC3-Ⅱ in SCI group and SS31 peptide group also increased, reached a peak at day 3 （0. 348± 0. 028, 0. 655 ±0. 052）, remained high level at day 7 （0. 301 ± 0. 053, 0. 432 ± 0. 052） and also showed high expression at day 14 （0.268 ±0.049, 0.371 ±0. 052） （P 〈0.05）. The expressions of Beclin-1 and LC3-Ⅱ in SS31 peptide group at day 3 after injury were 1. 841 ±0. 051 and 0. 455 ± 0.052, higher than that in SCI group （ 1. 478 ± 0.030, 0. 348 ± 0.028 ） （P 〈 0.05 ）. In SS31 peptide group at 6 h and days 1, 7 and 14 after injury, the expressions of Beclin-1 （ 0. 582 ± 0. 028, 0. 723 ±0.049, 1.551 ±0.032, 1.471 ±0.062） and LC3-Ⅱ （0. 172 ±0.031, 0.256 ±0.05l, 0. 432 ± 0. 052, 0. 371 ± 0. 052 ） had no significant difference in comparison with corresponding expressions of Beclin-1 （0.584 ± 0. 021, 0. 642 ± 0. 051, 1. 302 ± 0. 049, 1. 252 ± 0. 048） and LC3-Ⅱ （0. 156 ± 0.019, 0. 184±0.050, 0.301 ±0.053, 0.268±0.049） in SCI group （P〉0.05）. Cortelusion SS31 peptide can improve motor function and enhance the autophagy of nerve cells after SCI in rats, which may be one of the mechanisms for SS31 peptide treating spinal cord injury.
出处
《中华创伤杂志》
CAS
CSCD
北大核心
2017年第10期940-944,共5页
Chinese Journal of Trauma
基金
国家自然科学基金面上项目（81472136）
河南省科技厅科技攻关项目（172102310080）
