Wu Qiuhe, Xuan Weijun, Ando Takahiro, Xu Tao, Huang Liyi, Huang Ying-Ying, Dai Tianghong, Dhital Saphala, Sharma Sulbha K, Whalen Michael J, Hamblin Michael R
Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA.
Lasers Surg Med. 2012 Mar;44(3):218-26. doi: 10.1002/lsm.22003. Epub 2012 Jan 24.
Traumatic brain injury (TBI) affects millions worldwide and is without effective treatment. One area that is attracting growing interest is the use of transcranial low-level laser therapy (LLLT) to treat TBI. The fact that near-infrared light can penetrate into the brain would allow non-invasive treatment to be carried out with a low likelihood of treatment-related adverse events. LLLT may treat TBI by increasing respiration in the mitochondria, causing activation of transcription factors, reducing inflammatory mediators and oxidative stress, and inhibiting apoptosis.
STUDY DESIGN/MATERIALS AND METHODS: We tested LLLT in a mouse model of closed-head TBI produced by a controlled weight drop onto the skull. Mice received a single treatment with continuous-wave 665, 730, 810, or 980 nm lasers (36 J/cm(2) delivered at 150 mW/cm(2)) 4-hour post-TBI and were followed up by neurological performance testing for 4 weeks.
Mice with moderate-to-severe TBI treated with 665 and 810 nm laser (but not with 730 or 980 nm) had a significant improvement in Neurological Severity Score that increased over the course of the follow-up compared to sham-treated controls. Morphometry of brain sections showed a reduction in small deficits in 665 and 810 nm laser treated mouse brains at 28 days.
The effectiveness of 810 nm agrees with previous publications, and together with the effectiveness of 660 nm and non-effectiveness of 730 and 980 nm can be explained by the absorption spectrum of cytochrome oxidase, the candidate mitochondrial chromophore in transcranial LLLT.
创伤性脑损伤（TBI）在全球影响着数百万人，且尚无有效治疗方法。经颅低强度激光疗法（LLLT）用于治疗TBI这一领域正吸引着越来越多的关注。近红外光能够穿透大脑这一事实使得无创治疗得以开展，且治疗相关不良事件发生的可能性较低。LLLT可能通过增加线粒体呼吸、激活转录因子、减少炎症介质和氧化应激以及抑制细胞凋亡来治疗TBI。
研究设计/材料与方法：我们在通过控制重量撞击颅骨所产生的闭合性颅脑损伤小鼠模型中测试了LLLT。小鼠在创伤性脑损伤后4小时接受一次连续波665、730、810或980 nm激光治疗（以150 mW/cm²的功率递送36 J/cm²），并进行了4周的神经功能测试随访。
与假手术对照组相比，接受665和810 nm激光治疗（而非730或980 nm）的中重度创伤性脑损伤小鼠的神经严重程度评分有显著改善，且在随访过程中持续增加。脑切片形态学分析显示，在28天时，接受665和810 nm激光治疗的小鼠大脑中小缺损减少。
810 nm激光的有效性与先前的研究结果一致，660 nm激光的有效性以及730和980 nm激光的无效性可由细胞色素氧化酶的吸收光谱来解释，细胞色素氧化酶是经颅LLLT中候选的线粒体发色团。
