Chen K, Zhang L, Tan M, Lai C S W, Li A, Ren C, So K-F
Guangdong-Hong Kong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, China.
Guangdong Medical Key Laboratory of Brain Function and Diseases, Jinan University, Guangzhou, China.
Transl Psychiatry. 2017 Mar 21;7(3):e1069. doi: 10.1038/tp.2017.41.
Stress-related memory deficit is correlated with dendritic spine loss. Physical exercise improves memory function and promotes spinogenesis. However, no studies have been performed to directly observe exercise-related effects on spine dynamics, in association with memory function. This study utilized transcranial two-photon in vivo microscopy to investigate dendritic spine formation and elimination in barrel cortex of mice under physical constrain or naive conditions, followed by memory performance in a whisker-dependent novel texture discrimination task. We found that stressed mice had elevated spine elimination rate in mouse barrel cortex plus deficits in memory retrieval, both of which can be rescued by chronic exercise on treadmill. Exercise also elevated brain-derived neurotrophic factor (BDNF) expression in barrel cortex. The above-mentioned rescuing effects for both spinognesis and memory function were abolished after inhibiting BDNF/tyrosine kinase B (TrkB) pathway. In summary, this study demonstrated the improvement of stress-associated memory function by exercise via facilitating spine retention in a BDNF/TrkB-dependent manner.
应激相关的记忆缺陷与树突棘丢失相关。体育锻炼可改善记忆功能并促进树突棘生成。然而，尚未有研究直接观察运动对树突棘动态变化的影响及其与记忆功能的关系。本研究利用经颅双光子活体显微镜技术，观察在身体受限或正常条件下小鼠桶状皮层中树突棘的形成和消除情况，随后通过一项依赖触须的新颖纹理辨别任务评估其记忆表现。我们发现，应激小鼠的桶状皮层树突棘消除率升高，同时记忆提取存在缺陷，而这两者均可通过在跑步机上进行长期锻炼得到改善。运动还可提高桶状皮层中脑源性神经营养因子（BDNF）的表达。抑制BDNF/酪氨酸激酶B（TrkB）信号通路后，上述对树突棘生成和记忆功能的改善作用均被消除。总之，本研究表明运动通过BDNF/TrkB依赖性方式促进树突棘保留，从而改善应激相关的记忆功能。
