Xu Yang, Chen Min, Hu Bingbing, Huang Rongchen, Hu Bing
Chinese Academy of Sciences Key Laboratory of Brain Function and Disease, and School of Life Sciences, University of Science and Technology of China Hefei, China.
Front Cell Neurosci. 2017 Jan 24;11:4. doi: 10.3389/fncel.2017.00004. eCollection 2017.
Mitochondrial transport is essential for neuronal function, but the evidence of connections between mitochondrial transport and axon regeneration in the central nervous system (CNS) of living vertebrates remains limited. Here, we developed a novel model to explore mitochondrial transport in a single Mauthner axon (M axon) of zebrafish with non-invasive imaging. To confirm the feasibility of using this model, we treated labeled zebrafish with nocodazole and demonstrated that it could disrupt mitochondrial transport. We also used two-photon laser axotomy to precisely axotomize M axons and simultaneously recorded their regeneration and the process of mitochondrial transport in living zebrafish larvae. The findings showed that the injured axons with stronger regenerative capability maintain greater mitochondrial motility. Furthermore, to stimulate axon regeneration, treatment with dibutyryl cyclic adenosine monophosphate (db-cAMP) could also augment mitochondrial motility. Taken together, our results provide new evidence that mitochondrial motility is positively correlated with axon regeneration in the living vertebrate CNS. This promising model will be useful for further studies on the interaction between axon regeneration and mitochondrial dynamics, using various genetic and pharmacological techniques.
线粒体运输对神经元功能至关重要，但在活体脊椎动物的中枢神经系统（CNS）中，线粒体运输与轴突再生之间联系的证据仍然有限。在此，我们开发了一种新型模型，通过非侵入性成像来探索斑马鱼单个Mauthner轴突（M轴突）中的线粒体运输。为了证实使用该模型的可行性，我们用诺考达唑处理标记的斑马鱼，并证明它可以破坏线粒体运输。我们还使用双光子激光轴突切断术精确切断M轴突，并同时记录其在活体斑马鱼幼虫中的再生以及线粒体运输过程。研究结果表明，具有较强再生能力的受损轴突保持着更大的线粒体运动性。此外，为了刺激轴突再生，用二丁酰环磷酸腺苷（db-cAMP）处理也可以增强线粒体运动性。综上所述，我们的结果提供了新的证据，表明线粒体运动性与活体脊椎动物中枢神经系统中的轴突再生呈正相关。这个有前景的模型将有助于利用各种遗传和药理学技术，进一步研究轴突再生与线粒体动力学之间的相互作用。
