Low-energy extracorporeal shock wave therapy for promotion of vascular endothelial growth factor expression and angiogenesis and improvement of locomotor and sensory functions after spinal cord injury
Low-energy extracorporeal shock wave therapy for promotion of vascular endothelial growth factor expression and angiogenesis and improvement of locomotor and sensory functions after spinal cord injury
复制标题
DOI：
10.3171/2016.4.spine15923
复制
发表时间：
2016-12-01
影响因子：
2.8
通讯作者：
Itoi, Eiji
中科院分区：
文献类型：
--
作者：
Yahata, Kenichiro;Kanno, Haruo;Itoi, Eiji
目的体外冲击波疗法（ESWT）广泛用于治疗多种人类疾病。低能量 ESWT 可增加培养的内皮细胞中血管内皮生长因子 (VEGF) 的表达。 VEGF不仅刺激内皮细胞促进血管生成，而且刺激神经细胞产生神经保护作用。这些作者之前的一项研究表明，低能量 ESWT 促进受损神经组织中 VEGF 的表达，并改善脊髓损伤 (SCI) 后的运动功能。然而，低能量ESWT对受损脊髓产生的神经保护机制仍不清楚。在本研究中，作者研究了受损脊髓中 VEGF 表达的细胞特异性以及低能量 ESWT 诱导的血管生成。他们还研究了低能量ESWT对细胞死亡、轴突损伤和白质保留的神经保护作用，以及改善SCI后感觉功能的治疗效果。方法将成年雌性Sprague-Dawley大鼠分为SCI组（仅SCI）和SCI-SW组（SCI后应用低能量ESWT）。胸部 SCI 是使用纽约大学冲击器产生的。 SCI 后对受伤脊髓进行低能量 ESWT，每周 3 次，持续 3 周。 SCI 后 42 天，使用 Basso、Beattie 和 Bresnahan 旷场运动评分评估运动功能。评估后爪的机械性和热性异常疼痛 42 天。第 7 天进行 VEGF 和各种细胞类型标记物（NeuN、GFAP 和 Olig2）的双染色；在第 7 天也进行了 TUNEL 染色。对 SCI 后 42 天采集的脊髓切片进行 CD31、α-SMA 和 5-HT 的免疫组织化学染色。第 42 天进行 Luxol 坚蓝染色。 结果 低能量 ESWT 不仅显着改善运动，而且显着改善 SCI 后的机械和热异常性疼痛。在双重染色中，在 NeuN、GFAP 和 Olig2 标记的细胞中观察到 VEGF 的表达。低能量 ESWT 显着促进受损脊髓中 CD31 和 a-SMA 的表达。此外，低能量 ESWT 显着减少了受损脊髓中的 TUNEL 阳性细胞。此外，经低能量 ESWT 治疗的动物中 5-HT 阳性轴突的免疫密度显着较高。 Luxol固蓝染色显示，SCI-SW组未受损伤的白质面积明显大于SCI组。结论本研究结果表明，低能量ESWT可促进多种神经细胞中VEGF的表达，增强SCI后受损神经组织的血管生成。此外，低能量ESWT诱导的VEGF的神经保护作用可以抑制细胞死亡和轴突损伤，从而改善SCI后的运动和感觉功能。因此，低能量 ESWT 可能成为治疗 SCI 的一种新的治疗策略。
OBJECTIVE Extracorporeal shock wave therapy (ESWT) is widely used to treat various human diseases. Low-energy ESWT increases expression of vascular endothelial growth factor (VEGF) in cultured endothelial cells. The VEGF stimulates not only endothelial cells to promote angiogenesis but also neural cells to induce neuroprotective effects. A previous study by these authors demonstrated that low-energy ESWT promoted expression of VEGF in damaged neural tissue and improved locomotor function after spinal cord injury (SCI). However, the neuroprotective mechanisms in the injured spinal cord produced by low-energy ESWT are still unknown. In the present study, the authors investigated the cell specificity of VEGF expression in injured spinal cords and angiogenesis induced by low-energy ESWT. They also examined the neuroprotective effects of low-energy ESWT on cell death, axonal damage, and white matter sparing as well as the therapeutic effect for improvement of sensory function following SCI.METHODS Adult female Sprague-Dawley rats were divided into the SCI group (SCI only) and SCI-SW group (low-energy ESWT applied after SCI). Thoracic SCI was produced using a New York University Impactor. Low-energy ESWT was applied to the injured spinal cord 3 times a week for 3 weeks after SCI. Locomotor function was evaluated using the Basso, Beattie, and Bresnahan open-field locomotor score for 42 days after SCI. Mechanical and thermal allodynia in the hindpaw were evaluated for 42 days. Double staining for VEGF and various cell-type markers (NeuN, GFAP, and Olig2) was performed at Day 7; TUNEL staining was also performed at Day 7. Immunohistochemical staining for CD31, alpha-SMA, and 5-HT was performed on spinal cord sections taken 42 days after SCI. Luxol fast blue staining was performed at Day 42.RESULTS Low-energy ESWT significantly improved not only locomotion but also mechanical and thermal allodynia following SCI. In the double staining, expression of VEGF was observed in NeuN-, GFAP-, and Olig2-labeled cells. Low-energy ESWT significantly promoted CD31 and a-SMA expressions in the injured spinal cords. In addition, low-energy ESWT significantly reduced the TUNEL-positive cells in the injured spinal cords. Furthermore, the immunodensity of 5-HT positive axons was significantly higher in the animals treated by low-energy ESWT. The areas of spared white matter were obviously larger in the SCI-SW group than in the SCI group, as indicated by Luxol fast blue staining.CONCLUSIONS The results of this study suggested that low-energy ESWT promotes VEGF expression in various neural cells and enhances angiogenesis in damaged neural tissue after SCI. Furthermore, the neuroprotective effect of VEGF induced by low-energy ESWT can suppress cell death and axonal damage and consequently improve locomotor and sensory functions after SCI. Thus, low-energy ESWT can be a novel therapeutic strategy for treatment of SCI.