中国神经再生研究(英文版)

中国神经再生研究(英文版) ›› 2025, Vol. 20 ›› Issue (10): 2955-2968.doi: 10.4103/NRR.NRR-D-23-01933

• 原著:脊髓损伤修复保护与再生 • 上一篇    下一篇

抑制小胶质细胞内神经酰胺合成酶5表达保护损伤脊髓

  

  • 出版日期:2025-10-15 发布日期:2025-02-09

Inhibiting ceramide synthase 5 expression in microglia decreases neuroinflammation after spinal cord injury

Wei Zhang1, 2, 3, 4, #, Yubao Lu1, 2, 3, 4, #, Ruoqi Shen1, #, Yingjie Wu1 , Chenrui Liu1 , Xingxing Fang1 , Liangming Zhang1, 2, 3, 4, *, Bin Liu1, 2, 3, 4, *, Limin Rong1, 2, 3, 4, *   

  1. 1 Department of Spine Surgery, The Third Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong Province, China;  2 National Medical Products Administration (NMPA) Key Laboratory for Quality Research and Evaluation of Cell Products, Guangzhou, Guangdong Province, China;  3 Guangdong Provincial Center for Quality Control of Minimally Invasive Spine Surgery, Guangzhou, Guangdong Province, China;  4 Guangdong Provincial Center for Engineering and Technology Research of Minimally Invasive Spine Surgery, Guangzhou, Guangdong Province, China
  • Online:2025-10-15 Published:2025-02-09
  • Contact: Liangming Zhang, MD, PhD, zhanglm36@mail.sysu.edu.cn; Bin Liu, MD, PhD, liubin6@mail.sysu.edu.cn; Limin Rong, MD, PhD, ronglm@mail.sysu.edu.cn.
  • Supported by:
    This work was supported by grants from the National Key Research and Development Program of China, No. 2017YFA0105400 (to LR); the Key Research and Development Program of Guangdong Province, No. 2019B020236002 (to LR); and the National Natural Science Foundation of China, Nos. 81972111 (to LZ), 81772349 (to BL).

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摘要：

小胶质细胞是中枢神经系统中唯一的常驻的单核细胞-巨噬细胞，在脊髓损伤后的病理生理发展中起着至关重要的作用，但其具体作用尚不清楚。为探索小胶质细胞在脊髓损伤后的具体调控作用及分子机制，实验首先利用生物信息学技术对脊髓损伤后单细胞测序数据集进行分析，并重点探索了脊髓损伤后小胶质细胞在神经炎症反应中的细胞亚群变化及其可能的调控机制。结果显示，小胶质细胞MG1亚群在脊髓损伤后急性和亚急性期出现，并高表达细胞焦亡、鞘磷脂代谢和神经炎症相关基因。然后建立了脊髓挫伤小鼠模型，并通过鞘内注射siRNA和分子抑制剂来验证神经酰胺合成酶5在脊髓损伤后神经炎症反应和细胞死亡中的作用及机制，并通过PC12-BV2细胞共培养系统进一步验证神经酰胺合成酶5在体外脊髓损伤模型中小胶质细胞焦亡和神经炎症反应中的作用。可见，神经酰胺合成酶5和细胞焦亡相关蛋白在脊髓损伤后14d内高表达。在体内外脊髓损伤模型中抑制神经酰胺合成酶5表达可有效地减少细胞焦亡，并且神经酰胺合成酶5诱导的细胞焦亡依赖于NLRP3信号通路的激活。抑制小胶质细胞中CerS5表达可减少神经元凋亡，促进神经功能的恢复。进一步研究发现脊髓损伤后Pla2g7介导的鞘磷脂代谢与神经酰胺合成酶5参与的细胞焦亡之间存在串扰关系，且这种串扰调控机制与Pla2g7抑制NLRP3信号通路激活密切相关。综上，抑制脊髓损伤后小胶质细胞内CerS5表达能够有效抑制NLRP3信号通路介导的小胶质细胞焦亡，从而发挥神经保护作用。

https://orcid.org/0000-0003-2282-4687 (Liangming Zhang); https://orcid.org/0000-0001-9295-8176 (Bin Liu); 

https://orcid.org/0000-0003-0373-7393 (Limin Rong)

关键词: 神经酰胺合成酶5,  脊髓损伤,  神经炎症,  小胶质细胞,  鞘磷脂代谢,  焦亡,  Pla2g7,  NLRP3,  GSDMD,  NF-κB

Abstract: Microglia, the resident monocyte of the central nervous system, play a crucial role in the response to spinal cord injury. However, the precise mechanism remains unclear. To investigate the molecular mechanisms by which microglia regulate the neuroinflammatory response to spinal cord injury, we performed single-cell RNA sequencing dataset analysis, focusing on changes in microglial subpopulations. We found that the MG1 subpopulation emerged in the acute/subacute phase of spinal cord injury and expressed genes related to cell pyroptosis, sphingomyelin metabolism, and neuroinflammation at high levels. Subsequently, we established a mouse model of contusive injury and performed intrathecal injection of siRNA and molecular inhibitors to validate the role of ceramide synthase 5 in the neuroinflammatory responses and pyroptosis after spinal cord injury. Finally, we established a PC12-BV2 cell co-culture system and found that ceramide synthase 5 and pyroptosis-associated proteins were highly expressed to induce the apoptosis of neuron cells. Inhibiting ceramide synthase 5 expression in a mouse model of spinal cord injury effectively reduced pyroptosis. Furthermore, ceramide synthase 5-induced pyroptosis was dependent on activation of the NLRP3 signaling pathway. Inhibiting ceramide synthase 5 expression in microglia in vivo reduced neuronal apoptosis and promoted recovery of neurological function. Pla2g7 formed a “bridge” between sphingolipid metabolism and ceramide synthase 5-mediated cell death by inhibiting the NLRP3 signaling pathway. Collectively, these findings suggest that inhibiting ceramide synthase 5 expression in microglia after spinal cord injury effectively suppressed microglial pyroptosis mediated by NLRP3, thereby exerting neuroprotective effects.

Key words: ceramide synthase 5,  gasdermin D,  microglia,  neuroinflammation,  NLRP3,  nuclear factor kappa B,  Pla2g7,  pyroptosis,  sphingomyelin metabolism,  spinal cord injury