Pan Xiaona, Jiang Ting, Zhang Liying, Zheng Haiqing, Luo Jing, Hu Xiquan
Department of Rehabilitation Medicine, Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
Front Behav Neurosci. 2017 Nov 8;11:185. doi: 10.3389/fnbeh.2017.00185. eCollection 2017.
Cerebral ischemia leads to memory impairment, and several studies have indicated that physical exercise (PE) has memory-improving effects after ischemia. This study was designed to further explore the specific role of PE in novel object recognition (NOR) memory after stroke and the exact cortical regions in which memory is restored by PE. Spontaneously hypertensive rats (SHR) were subjected to transient middle cerebral artery occlusion (tMCAO) or sham surgery, followed by 26 days of PE starting on day 3 post-tMCAO. Thereafter, infarct volume, neurobehavioral outcome and NOR memory were assessed. Immunofluorescence staining and Luxol Fast Blue (LFB) staining were performed in the prefrontal cortex, entorhinal cortex and corpus callosum regions. Western blot analysis was performed to detect expressions of Nestin, Bcl-2 and SYN proteins in the entorhinal cortex. After tMCAO, NOR memory impairment was found in SHR. Rats subjected to PE post-tMCAO showed increased discrimination ratio, as well as significant decreases in infarct volumes and modified neurological severity scores (mNSS), when compared with tMCAO rats without PE. After stroke, NeuN-positive cell number was drastically reduced in the entorhinal cortex, rather than in the prefrontal cortex. Ischemic stroke had no impact on myelin and phospholipids, and the ratio of SMI-32/MBP in the corpus callosum. PE increased NeuN, Nestin, Ki67, MBP, SYN, PSD-95 and Bcl-2 expressions in the entorhinal cortex, while TUNEL and SMI-32 expressions were decreased. In conclusion, the NOR memory-improving capacity promoted by PE was closely related to neuronal cell proliferation and synaptic plasticity of the entorhinal cortex.
脑缺血会导致记忆障碍，多项研究表明，体育锻炼（PE）对缺血后的记忆有改善作用。本研究旨在进一步探讨体育锻炼在中风后新物体识别（NOR）记忆中的具体作用，以及体育锻炼恢复记忆的确切皮质区域。将自发性高血压大鼠（SHR）进行短暂性大脑中动脉闭塞（tMCAO）或假手术，然后在tMCAO术后第3天开始进行26天的体育锻炼。此后，评估梗死体积、神经行为结果和NOR记忆。在前额叶皮质、内嗅皮质和胼胝体区域进行免疫荧光染色和Luxol Fast Blue（LFB）染色。进行蛋白质免疫印迹分析以检测内嗅皮质中巢蛋白、Bcl-2和SYN蛋白的表达。tMCAO后，在SHR中发现NOR记忆障碍。与未进行体育锻炼的tMCAO大鼠相比，tMCAO后进行体育锻炼的大鼠辨别率增加，梗死体积和改良神经功能缺损评分（mNSS）显著降低。中风后，内嗅皮质中NeuN阳性细胞数量急剧减少，而不是前额叶皮质。缺血性中风对胼胝体中的髓磷脂和磷脂以及SMI-32/MBP比值没有影响。体育锻炼增加了内嗅皮质中NeuN、巢蛋白、Ki67、MBP、SYN、PSD-95和Bcl-2的表达，而TUNEL和SMI-32的表达降低。总之，体育锻炼促进的NOR记忆改善能力与内嗅皮质的神经元细胞增殖和突触可塑性密切相关。
