中国神经再生研究(英文版) ›› 2024, Vol. 19 ›› Issue (6): 1325-1335.doi: 10.4103/1673-5374.385313

• 原著:脑损伤修复保护与再生 • 上一篇    下一篇

线粒体移植抑制缺血性脑卒中后小胶质细胞凋亡和促进神经发生

  

  • 出版日期:2024-06-15 发布日期:2023-11-17

Mitochondrial transplantation confers protection against the effects of ischemic stroke by repressing microglial pyroptosis and promoting neurogenesis

Li Sun1, 2, #, Zhaoyan Zhao2, #, Jing Guo1, #, Yuan Qin2, Qian Yu2, Xiaolong Shi2, Fei Guo2, Haiqin Zhang2, Xude Sun2, *, Changjun Gao2, *, Qian Yang1, *   

  1. 1Department of Experimental Surgery, The Second Affiliated Hospital of Air Force Medical University, Xi’an, Shaanxi Province, China; 2Department of Anesthesiology, The Second Affiliated Hospital of Air Force Medical University, Xi’an, Shaanxi Province, China
  • Online:2024-06-15 Published:2023-11-17
  • Contact: Qian Yang, MD, PhD, qianyang@fmmu.edu.cn; Changjun Gao, MD, gaocj74@163.com; Xude Sun, MD, sunxude@fmmu.edu.cn.
  • Supported by:
    This work was supported by the National Natural Science Foundation of China, Nos. 82201621 (to LS), 31930048 (to QY) and 81720108016  (to QY), and 81971225 (to CG), the Key Research and Development Project of Shaanxi Province, No. 2022SF-189 (to XS), and the Tangdu Hospital Supporting Foundation, Nos. 2021ZTXM-006 (to LS) and 2021JSZH-006 (to CG).

摘要:

已经研究表明,将健康的功能线粒体移植到大鼠侧脑室,对缺血再灌注损伤具有神经保护作用。但采取便于临床转化的静脉给药方式对于局灶性永久性缺血损伤是否具有保护作用,以及其有效的调控方式仍不明确。为此,实验给予光血栓局灶性缺血模型小鼠尾静脉或原位注射新鲜线粒体。通过动物行为测试、免疫荧光染色、TTC染色、mRNA-seq和Western blot观察小鼠的焦虑、记忆、皮质梗死面积、热休克和神经发生。通过生物信息分析、Western印迹、共免疫沉淀和质谱分析找到了线粒体功能的可能调控因子-S100A9及其相互作用蛋白。在体外,测试了外源线粒体与内源线粒体的相互作用以及对受体小胶质细胞的影响。结果显示:(1)线粒体移植可显著降低脑卒中后小鼠的死亡率,促进焦虑样情绪和认知功能的恢复,减少脑皮质梗死面积,抑制皮层的焦亡,并促进神经发生;(2)缺血损伤引起小胶质细胞显著增加的S100A9可调节移植线粒体的功效;(3)在培养的小胶质细胞内,外源线粒体在与内源线粒体融合后,能增强线粒体功能、降低氧化还原应激、调节小胶质细胞极化,并抑制焦亡;(4)S100A9可影响外源线粒体在小胶质细胞的内化,从而增强了其促增殖和抗焦亡的作用。总之,线粒体移植通过抑制焦亡和促进神经发生对缺血性脑卒中发挥保护作用,而且S100A9在促进外源线粒体内化方面起着至关重要的作用。

https://orcid.org/0000-0001-9538-936X (Qian Yang); https://orcid.org/0000-0002-5860-6596 (Changjun Gao); https://orcid.org/0000-0002-8365-0644 (Xude Sun)

Abstract: Transferring healthy and functional mitochondria to the lateral ventricles confers neuroprotection in a rat model of ischemia-reperfusion injury. Autologous mitochondrial transplantation is also beneficial in pediatric patients with cardiac ischemia-reperfusion injury. Thus, transplantation of functional exogenous mitochondria may be a promising therapeutic approach for ischemic disease. To explore the neuroprotective effect of mitochondria transplantation and determine the underlying mechanism in ischemic stroke, in this study we established a photo-thrombosis-induced mouse model of focal ischemia and administered freshly isolated mitochondria via the tail vein or to the injury site (in situ). Animal behavior tests, immunofluorescence staining, 2,3,5-triphenyltetrazolium chloride (TTC) staining, mRNA-seq, and western blotting were used to assess mouse anxiety and memory, cortical infarct area, pyroptosis, and neurogenesis, respectively. Using bioinformatics analysis, western blotting, co-immunoprecipitation, and mass spectroscopy, we identified S100 calcium binding protein A9 (S100A9) as a potential regulator of mitochondrial function and determined its possible interacting proteins. Interactions between exogenous and endogenous mitochondria, as well as the effect of exogenous mitochondria on recipient microglia, were assessed in vitro. Our data showed that: (1) mitochondrial transplantation markedly reduced mortality and improved emotional and cognitive function, as well as reducing infarct area, inhibiting pyroptosis, and promoting cortical neurogenesis; (2) microglial expression of S100A9 was markedly increased by ischemic injury and regulated mitochondrial function; (3) in vitro, exogenous mitochondria enhanced mitochondrial function, reduced redox stress, and regulated microglial polarization and pyroptosis by fusing with endogenous mitochondria; and (4) S100A9 promoted internalization of exogenous mitochondria by the microglia, thereby amplifying their pro-proliferation and anti-inflammatory effects. Taken together, our findings show that mitochondrial transplantation protects against the deleterious effects of ischemic stroke by suppressing pyroptosis and promoting neurogenesis, and that S100A9 plays a vital role in promoting internalization of exogenous mitochondria.

Key words: ischemic stroke, microglia, mitochondria transplantation, neurogenesis, pyroptosis