中国神经再生研究(英文版) ›› 2023, Vol. 18 ›› Issue (10): 2252-2259.doi: 10.4103/1673-5374.369120

• 原著:脊髓损伤修复保护与再生 • 上一篇    下一篇

P物质通过诱导巨噬细胞的M2分化促进脊髓硬膜外纤维化

  

  • 出版日期:2023-10-15 发布日期:2023-03-28
  • 基金资助:
    国家自然科学基金项目(82172486,82171738,81671563);江苏省卫计委项目(JSWST-028)、江苏省六一项目(LGY2016018);江苏省六大人才高峰项目(WSW-040)

Substance P promotes epidural fibrosis via induction of type 2 macrophages

Feng Hua1, #, Hao-Ran Wang1, #, Yun-Feng Bai1, Jin-Peng Sun1, Wei-Shun Wang2, Ying Xu3, Ming-Shun Zhang4, *, Jun Liu1, *   

  1. 1Department of Orthopedics, The Second Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China; 2Department of Orthopedics, Sir Run Run Hospital, Nanjing Medical University, Nanjing, Jiangsu Province, China; 3Department of Intensive Care Unit, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China; 4NHC Key Laboratory of Antibody Technique, Jiangsu Province Engineering Research Center of Antibody Drug, Department of Immunology, Nanjing Medical University, Nanjing, Jiangsu Province, China
  • Online:2023-10-15 Published:2023-03-28
  • Contact: Ming-Shun Zhang, MD, PhD, mingshunzhang@njmu.edu.cn; Jun Liu, MD, 13776698080@139.com.
  • Supported by:
    This study was supported by the National Natural Science Foundation of China, Nos. 82172486 (to JL), 82171738 (to MSZ), 81671563 (to MSZ), Jiangsu Provincial Commission of Health and Family Planning, No. JSWST-028 (to JL), “Six One” Project of Jiangsu Province, No. LGY2016018 (to JL) and Jiangsu Provincial Personnel Department “the Great of Six Talented Man Peak” Project, No. WSW-040 (to JL).

摘要:

脊柱手术后,神经元会向硬膜外部位分泌大量P物质,而后者与巨噬细胞分化和瘢痕纤维化疾病有关,但是P物质在硬膜外瘢痕纤维化中的具体作用和机制仍不清楚。为此,实验构建了L1-L3椎板切除小鼠模型,可见背根神经节神经元以及伤口部位浸润的巨噬细胞能释放P物质。进而在体外实验中发现,M1巨噬细胞分泌的P物质能促进M1巨噬细胞向M2巨噬细胞的分化。接下来的高通量mRNA测序结果表明,鞘脂代谢通路可能参与P物质调节M2分化。具体而言,鞘磷脂代谢通路中的鞘磷脂合成酶2可促进P物质调节巨噬细胞的M2分化。且鞘磷脂合成酶2抑制剂LY93抑制鞘磷脂合成酶2可抑制M2分化。此外,P物质还能促进中性粒细胞胞外陷阱网的形成,进一步促进M2分化。最后在椎板摘除小鼠模型中发现,P物质受体抑制剂RP67580可显著减少伤口部位M2巨噬细胞,减轻硬膜外瘢痕,并降低瘢痕组织中纤维连接蛋白、α-平滑肌肌动蛋白和I型胶原含量。上述结果表明,P物质可通过鞘磷脂合成酶2和中性粒细胞胞外陷阱网促进硬膜外纤维化中巨噬细胞的M2分化,这将为治疗硬膜外瘢痕提供了新的策略。

https://orcid.org/0000-0001-5925-0168 (Ming-Shun Zhang); https://orcid.org/0000-0003-3756-3627 (Jun Liu)

关键词: 硬膜外纤维化, 巨噬细胞, P物质, 鞘磷脂合酶2, 中性粒细胞胞外陷阱网, 椎板切除, 线粒体, 背根神经节, 神经激肽受体1

Abstract: In response to spinal surgery, neurons secrete a large amount of substance P into the epidural area. Substance P is involved in macrophage differentiation and fibrotic disease. However, the specific roles and mechanisms of substance P in epidural fibrosis remain unclear. In this study, we established a mouse model of L1–L3 laminectomy and found that dorsal root ganglion neurons and the macrophages infiltrating into the wound area released sphingolipids. In vitro experiments revealed that type 1 macrophages secreted substance P, which promoted differentiation of type 1 macrophages towards a type 2 phenotype. High-throughput mRNA-seq analysis revealed that the sphingolipid metabolic pathway may be involved in the regulation of type 2 macrophages by substance P. Specifically, sphingomyelin synthase 2, a component of the sphingolipid metabolic pathway, promoted M2 differentiation in substance P-treated macrophages, while treating the macrophages with LY93, a sphingomyelin synthase 2 inhibitor, suppressed M2 differentiation. In addition, substance P promoted the formation of neutrophil extracellular traps, which further boosted M2 differentiation. Blocking substance P with the neurokinin receptor 1 inhibitor RP67580 decreased the number of M2 macrophages in the wound area after spinal surgery and alleviated epidural fibrosis, as evidenced by decreased fibronectin, α-smooth muscle actin, and collagen I in the scar tissue. These results demonstrated that substance P promotes M2 macrophage differentiation in epidural fibrosis via sphingomyelin synthase 2 and neutrophil extracellular traps. These findings provide a novel strategy for the treatment of epidural fibrosis.

Key words: dorsal root ganglion, epidural fibrosis, laminectomy, macrophage, mitochondria, neurokinin receptor 1, neutrophil extracellular traps, sphingomyelin synthase 2, substance P