PDF(Pubmed)
Abstract：
Volumetric muscle loss (VML) injury causes irreversible deficits in muscle mass and function, often resulting in permanent disability. The current standard of care is physical therapy, but it is limited in mitigating functional deficits. We have previously optimized a rehabilitation technique using electrically stimulated eccentric contraction training (EST) that improved muscle mass, strength, and size in VML-injured rats. A biosponge scaffold composed of extracellular matrix proteins has previously enhanced muscle function postVML. This study aimed to determine whether combining a regenerative therapy (i.e., biosponge) with a novel rehabilitation technique (i.e., EST) could enhance recovery in a rat model of VML. A VML defect was created by removing ~20% of muscle mass from the tibialis anterior muscle in adult male Lewis rats. Experimental groups included VML-injured rats treated with biosponge with EST or biosponge alone (n = 6/group). EST was implemented 2 weeks postinjury at 150 Hz and was continued for 4 weeks. A linear increase in eccentric torque over 4 weeks showed the adaptability of the VML-injured muscle to EST. Combining biosponge with EST improved peak isometric torque by ~52% compared with biosponge treatment alone at 6 weeks postinjury. Application of EST increased MyoD gene expression and the percentage of large (>2000 μm2) type 2B myofibers but reduced fibrotic tissue deposition in VML-injured muscles. Together, these changes may provide the basis for improved torque production. This study demonstrates the potential for combined regenerative and rehabilitative therapy to improve muscle recovery following VML.
摘要：
肌肉体积损失（VML）损伤导致肌肉质量和功能不可逆的缺陷，往往导致永久性残疾。目前的护理标准是物理治疗，但它在减轻功能缺陷方面是有限的。我们以前优化了一种康复技术，使用电刺激偏心收缩训练（EST），改善肌肉质量，力量,VML损伤大鼠的大小。由细胞外基质蛋白组成的生物海绵支架先前在VML后增强了肌肉功能。这项研究旨在确定是否结合再生疗法(即，生物海绵)与一种新的康复技术(即，EST）可以增强VML大鼠模型的恢复。通过从成年雄性Lewis大鼠的胫骨前肌中去除约20％的肌肉质量来产生VML缺陷。实验组包括用EST生物海绵或单独的生物海绵处理的VML损伤大鼠(n=6/组)。EST在150Hz受伤后2周实施，并持续4周。偏心扭矩在4周内的线性增加表明VML损伤的肌肉对EST的适应性。在损伤后6周时，与单独的生物海绵治疗相比，将生物海绵与EST结合可将峰值等距扭矩提高约52％。EST的应用增加了MyoD基因表达和大（>2000μm2）2B型肌纤维的百分比，但减少了VML损伤肌肉中的纤维化组织沉积。一起,这些变化可以为提高扭矩生产提供基础。这项研究证明了再生和康复联合治疗改善VML后肌肉恢复的潜力。
