Post-Graduation Program of Neurosciences, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Área de Conhecimento de Ciências da Vida, Universidade de Caxias do Sul, Caxias do Sul, RS, Brazil; Cerebral Ischemia and Neuroprotection Laboratotory, Biochemistry Department, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Post-Graduation Program of Neurosciences, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Cerebral Ischemia and Neuroprotection Laboratotory, Biochemistry Department, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Neuroscience. 2018 Nov 10;392:258-269. doi: 10.1016/j.neuroscience.2018.08.033. Epub 2018 Sep 6.
Locomotor training (LT) has been exhaustively investigated as a treatment for the spinal cord injury (SCI), however the literature reports both positive and negative effects over the functional recovery. The initiation period of LT following SCI is one of the major variables that needs attention. To investigate the better period, three different starting times were investigated after SCI in rats. Methods: Wistar rats were randomly divided into groups: control, SCI (rats with spinal cord contusion), and SCI groups exposed to LT starting 7, 14 or 28 days after the injury (SCI-T7, SCI-T14 and SCI-T28). LT was performed on a treadmill, five days a week, 20 minutes per day, for ten weeks. Basso, Breattie and Bresnahan (BBB) scale and Horizontal Ladder walking test were used to evaluate the motor function; at the end, morphological and biochemical analyses of the spinal cords, tibialis anterior and soleus muscles were performed. Results: SCI-T14 and SCI-T28 groups had an improvement in both behavioral tests, while SCI-T7 presented a worsening in the functional performance. Late training groups preserved motoneurons in the spinal cord, showed larger muscle fiber areas and higher BDNF expression in tibialis anterior muscle. SCI-T7 group had higher lesion volume after LT in comparison with the SCI group. Late onset of LT promoted an increment of the hindlimb function, while early onset of training worsened the functional recovery of the SCI animals. These results demonstrate a critical LT starting time after the injury, contributing to define the best therapeutic window for rehabilitation.
运动训练（LT）已被广泛研究作为脊髓损伤（SCI）的治疗方法，然而，文献报告其对功能恢复的影响既有积极的，也有消极的。SCI 后开始 LT 的起始时间是需要关注的主要变量之一。为了研究更好的时间段，在大鼠 SCI 后研究了三个不同的起始时间。方法：Wistar 大鼠随机分为对照组、SCI（脊髓挫伤大鼠）和 SCI 组，分别在损伤后 7、14 或 28 天开始 LT（SCI-T7、SCI-T14 和 SCI-T28）。LT 在跑步机上进行，每周 5 天，每天 20 分钟，共 10 周。Basso、Breattie 和 Bresnahan（BBB）量表和水平梯行走试验用于评估运动功能；最后，对脊髓、胫骨前肌和比目鱼肌进行形态学和生化分析。结果：SCI-T14 和 SCI-T28 组在行为测试中均有改善，而 SCI-T7 组在功能表现上则恶化。晚期训练组保留了脊髓中的运动神经元，胫骨前肌的肌纤维面积较大，BDNF 表达较高。与 SCI 组相比，LT 后 SCI-T7 组的损伤体积更大。LT 起始时间较晚可促进后肢功能的提高，而早期开始训练则会使 SCI 动物的功能恢复恶化。这些结果表明损伤后 LT 的起始时间存在关键期，有助于确定康复的最佳治疗窗口。
