Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, SP, Brazil.
Brain Res. 2011 Nov 24;1425:111-22. doi: 10.1016/j.brainres.2011.10.004. Epub 2011 Oct 6.
Exercise is known to improve cognitive functions and to induce neuroprotection. In this study we used a short-term, moderate intensity treadmill exercise protocol to investigate the effects of exercise on usual markers of hippocampal synaptic and structural plasticity, such as synapsin I (SYN), synaptophysin (SYP), neurofilaments (NF), microtubule-associated protein 2 (MAP2), glutamate receptor subunits GluR1 and GluR2/3, brain-derived neurotrophic factor (BDNF) and glial fibrillary acidic protein (GFAP). Immunohistochemistry, Western blotting and real-time PCR were used. We also evaluated the number of cells positive for the proliferation marker 5-bromo-2-deoxyuridine (BrdU), the neurogenesis marker doublecortin (DCX) and the plasma corticosterone levels. Adult male Wistar rats were adapted to a treadmill and divided into 4 groups: sedentary (SED), 3-day exercise (EX3), 7-day exercise (EX7) and 15-day exercise (EX15). The protein changes detected were increased levels of NF68 and MAP2 at EX3, of SYN at EX7 and of GFAP at EX15, accompanied by a decreased level of GluR1 at EX3. Immunohistochemical findings revealed a similar pattern of changes. The real-time PCR analysis disclosed only an increase of MAP2 mRNA at EX7. We also observed an increased number of BrdU-positive cells and DCX-positive cells in the subgranular zone of the dentate gyrus at all time points and increased corticosterone levels at EX3 and EX7. These results reveal a positive effect of short-term, moderate treadmill exercise on hippocampal plasticity. This effect was in general independent of transcriptional processes and of BDNF upregulation, and occurred even in the presence of increased corticosterone levels.
运动被认为可以改善认知功能并诱导神经保护。在这项研究中，我们使用了短期、中等强度的跑步机运动方案，来研究运动对海马突触和结构可塑性的常见标志物的影响，如突触素 I (SYN)、突触小泡蛋白 (SYP)、神经丝 (NF)、微管相关蛋白 2 (MAP2)、谷氨酸受体亚基 GluR1 和 GluR2/3、脑源性神经营养因子 (BDNF) 和胶质纤维酸性蛋白 (GFAP)。我们使用了免疫组织化学、Western blot 和实时 PCR 等方法。我们还评估了增殖标志物 5-溴-2-脱氧尿苷 (BrdU)、神经发生标志物双皮质素 (DCX) 和血浆皮质酮水平阳性的细胞数量。成年雄性 Wistar 大鼠适应跑步机后分为 4 组：安静对照组 (SED)、3 天运动组 (EX3)、7 天运动组 (EX7) 和 15 天运动组 (EX15)。检测到的蛋白变化包括 EX3 时 NF68 和 MAP2 水平升高，EX7 时 SYN 水平升高，EX15 时 GFAP 水平升高，同时 EX3 时 GluR1 水平降低。免疫组织化学结果显示出相似的变化模式。实时 PCR 分析仅显示 EX7 时 MAP2 mRNA 增加。我们还观察到，在齿状回颗粒下区，所有时间点 BrdU 阳性细胞和 DCX 阳性细胞的数量增加，EX3 和 EX7 时皮质酮水平升高。这些结果表明，短期、中等强度的跑步机运动对海马可塑性有积极影响。这种影响通常不依赖于转录过程和 BDNF 的上调，即使在皮质酮水平升高的情况下也会发生。
