Ishiguro Motoi, Ikeda Kazuo, Tomita Katsuro
Department of Orthopaedic Surgery, Graduate School of Medicine, Kanazawa University, 13-1 Takara-machi, Kanazawa, Ishikawa, 920-8641, Japan.
J Orthop Sci. 2010 Mar;15(2):233-9. doi: 10.1007/s00776-009-1438-4. Epub 2010 Apr 1.
Photobiomodulation by red to near-infrared light-emitting diodes (LEDs) has been reported to accelerate wound healing, attenuate degeneration of an injured optic nerve, and promote tissue growth. The purpose of this study was to investigate the effect of LEDs on nerve regeneration. A histological study as well as a measurement of antioxidation levels in the nerve regeneration chamber fluid was performed.
For the histological study, the bilateral sciatic nerves were transected, and the left proximal stump and the right distal stump were inserted into the opposite ends of a silicone chamber, leaving a 10-mm gap. Light from an LED device (660 nm, 7.5 mW/cm(2)) was irradiated for 1 h per day. At 3 weeks after surgery, regenerated tissue was fixed and examined by light microscopy. For the antioxidation assay of chamber fluid, the left sciatic nerve and a 2-mm piece of nerve from the proximal stump were transected and inserted into opposite sides of a silicone chamber leaving a 10-mm gap. LEDs were irradiated using the same parameters as those described in the histological study. At 1, 3, and 7 days after surgery, antioxidation of the chamber fluid was measured using an OXY absorbent test.
Nerve regeneration was promoted in the LED group. Antioxidation of the chamber fluid significantly decreased from 3 days to 7 days in the control group. In the LED group, antioxidation levels did not decrease until 7 days.
Chamber fluid is produced from nerve stumps after nerve injury. This fluid contains neurotrophic factors that may accelerate axonal growth. Red to near-infrared LEDs have been shown to promote mitochondrial oxidative metabolism. In this study, LED irradiation improved nerve regeneration and increased antioxidation levels in the chamber fluid. Therefore, we propose that antioxidation induced by LEDs may be conducive to nerve regeneration.
据报道，红色至近红外发光二极管（LED）进行的光生物调节可加速伤口愈合、减轻受损视神经的退化并促进组织生长。本研究的目的是探讨LED对神经再生的影响。进行了组织学研究以及神经再生腔室液中抗氧化水平的测量。
对于组织学研究，双侧坐骨神经被切断，左近端残端和右远端残端插入硅胶腔室的相对两端，留出10毫米的间隙。每天用LED装置（660纳米，7.5毫瓦/平方厘米）照射1小时。术后3周，将再生组织固定并通过光学显微镜检查。对于腔室液的抗氧化测定，切断左侧坐骨神经和近端残端的一段2毫米神经，将其插入硅胶腔室的相对两侧，留出10毫米的间隙。使用与组织学研究中描述的相同参数照射LED。术后1、3和7天，使用OXY吸收剂测试测量腔室液的抗氧化能力。
LED组神经再生得到促进。对照组腔室液的抗氧化能力在术后3天至7天显著下降。在LED组中，抗氧化水平直到7天才下降。
神经损伤后神经残端会产生腔室液。这种液体含有可能加速轴突生长的神经营养因子。红色至近红外LED已被证明可促进线粒体氧化代谢。在本研究中，LED照射改善了神经再生并提高了腔室液中的抗氧化水平。因此，我们提出LED诱导的抗氧化作用可能有利于神经再生。
