Sun Cheng-Cheng, Zhang Yu-Wen, Xing Xiang-Xin, Yang Qi, Cao Ling-Yun, Cheng Yu-Feng, Zhao Jing-Wang, Zhou Shao-Ting, Cheng Dan-Dan, Zhang Ye, Hua Xu-Yun, Wang He, Xu Dong-Sheng
Department of Rehabilitation, Tongji Hospital, School of Medicine, Tongji University, Shanghai, China.
Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China.
Neural Regen Res. 2023 Feb;18(2):410-415. doi: 10.4103/1673-5374.344832.
Modified constraint-induced movement therapy (mCIMT) has shown beneficial effects on motor function improvement after brain injury, but the exact mechanism remains unclear. In this study, amplitude of low frequency fluctuation (ALFF) metrics measured by resting-state functional magnetic resonance imaging was obtained to investigate the efficacy and mechanism of mCIMT in a control cortical impact (CCI) rat model simulating traumatic brain injury. At 3 days after control cortical impact model establishment, we found that the mean ALFF (mALFF) signals were decreased in the left motor cortex, somatosensory cortex, insula cortex and the right motor cortex, and were increased in the right corpus callosum. After 3 weeks of an 8-hour daily mCIMT treatment, the mALFF values were significantly increased in the bilateral hemispheres compared with those at 3 days postoperatively. The mALFF signal values of left corpus callosum, left somatosensory cortex, right medial prefrontal cortex, right motor cortex, left postero dorsal hippocampus, left motor cortex, right corpus callosum, and right somatosensory cortex were increased in the mCIMT group compared with the control cortical impact group. Finally, we identified brain regions with significantly decreased mALFF values at 3 days postoperatively. Pearson correlation coefficients with the right forelimb sliding score indicated that the improvement in motor function of the affected upper limb was associated with an increase in mALFF values in these brain regions. Our findings suggest that functional cortical plasticity changes after brain injury, and that mCIMT is an effective method to improve affected upper limb motor function by promoting bilateral hemispheric cortical remodeling. mALFF values correlate with behavioral changes and can potentially be used as biomarkers to assess dynamic cortical plasticity after traumatic brain injury.
改良强制性运动疗法（mCIMT）已显示出对脑损伤后运动功能改善的有益效果，但其确切机制仍不清楚。在本研究中，通过静息态功能磁共振成像测量低频振幅（ALFF）指标，以研究mCIMT在模拟创伤性脑损伤的对照皮质撞击（CCI）大鼠模型中的疗效和机制。在对照皮质撞击模型建立后3天，我们发现左侧运动皮层、体感皮层、岛叶皮层和右侧运动皮层的平均ALFF（mALFF）信号降低，而右侧胼胝体的信号增强。在每天进行8小时的mCIMT治疗3周后，与术后3天相比，双侧半球的mALFF值显著增加。与对照皮质撞击组相比，mCIMT组左侧胼胝体、左侧体感皮层、右侧内侧前额叶皮层、右侧运动皮层、左侧后背部海马体、左侧运动皮层、右侧胼胝体和右侧体感皮层的mALFF信号值增加。最后，我们确定了术后3天mALFF值显著降低的脑区。与右前肢滑动评分的Pearson相关系数表明，受影响上肢运动功能的改善与这些脑区mALFF值的增加有关。我们的研究结果表明，脑损伤后存在功能性皮质可塑性变化，mCIMT是通过促进双侧半球皮质重塑来改善受影响上肢运动功能的有效方法。mALFF值与行为变化相关，有可能作为评估创伤性脑损伤后动态皮质可塑性的生物标志物。
