Neuroscience Center, Massachusetts General Hospital, Harvard Medical School, Charlestown, Massachusetts, USA.
J Neurotrauma. 2012 Jan 20;29(2):408-17. doi: 10.1089/neu.2010.1745. Epub 2011 Sep 21.
Low-level laser light therapy (LLLT) exerts beneficial effects on motor and histopathological outcomes after experimental traumatic brain injury (TBI), and coherent near-infrared light has been reported to improve cognitive function in patients with chronic TBI. However, the effects of LLLT on cognitive recovery in experimental TBI are unknown. We hypothesized that LLLT administered after controlled cortical impact (CCI) would improve post-injury Morris water maze (MWM) performance. Low-level laser light (800 nm) was applied directly to the contused parenchyma or transcranially in mice beginning 60-80 min after CCI. Injured mice treated with 60 J/cm² (500 mW/cm²×2 min) either transcranially or via an open craniotomy had modestly improved latency to the hidden platform (p<0.05 for group), and probe trial performance (p<0.01) compared to non-treated controls. The beneficial effects of LLLT in open craniotomy mice were associated with reduced microgliosis at 48 h (21.8±2.3 versus 39.2±4.2 IbA-1+ cells/200×field, p<0.05). Little or no effect of LLLT on post-injury cognitive function was observed using the other doses, a 4-h administration time point and 7-day administration of 60 J/cm². No effect of LLLT (60 J/cm² open craniotomy) was observed on post-injury motor function (days 1-7), brain edema (24 h), nitrosative stress (24 h), or lesion volume (14 days). Although further dose optimization and mechanism studies are needed, the data suggest that LLLT might be a therapeutic option to improve cognitive recovery and limit inflammation after TBI.
低水平激光疗法（LLLT）对实验性创伤性脑损伤（TBI）后的运动和组织病理学结果有有益影响，相干近红外光已被报道可改善慢性 TBI 患者的认知功能。然而，LLLT 对实验性 TBI 后认知恢复的影响尚不清楚。我们假设，在皮质控制冲击（CCI）后给予 LLLT 将改善损伤后的莫里斯水迷宫（MWM）表现。低水平激光（800nm）在 CCI 后 60-80 分钟开始直接施加于挫伤实质或颅外。用 60J/cm²（500mW/cm²×2min）治疗的受伤小鼠经颅或通过开颅术治疗，潜伏期至隐藏平台略有改善（组间 p<0.05），并且探针试验表现（p<0.01）与未经治疗的对照组相比。LLLT 在开颅手术小鼠中的有益作用与 48 小时时小胶质细胞减少有关（21.8±2.3 与 39.2±4.2 IbA-1+细胞/200×场，p<0.05）。使用其他剂量、4 小时给药时间点和 7 天 60J/cm² 的 LLLT 对损伤后认知功能几乎没有影响。在损伤后运动功能（第 1-7 天）、脑水肿（24 小时）、硝化应激（24 小时）或病变体积（14 天）上，均未观察到 LLLT（60J/cm² 开颅术）的作用。尽管需要进一步的剂量优化和机制研究，但数据表明，LLLT 可能是改善 TBI 后认知恢复和限制炎症的治疗选择。
