中文摘要：背景：成纤维细胞生长因子受体（FGFR）是神经再生和修复的关键靶点。由于外源重组FGF分子量高，其在体内的治疗效果受限。小肽具有分子量低、易扩散、低免疫原性和代谢物无毒等特点，是潜在的候选肽。本研究旨在开发一种新型低分子量的FGFR肽激动剂，以促进神经损伤的修复。
  方法：采用噬菌体展示技术筛选靶向FGFR2的肽配体；通过等温滴定量热法检测FGFR与肽配体的亲和力；采用基于结构生物学的计算机虚拟分析来表征肽配体与FGFR2的相互作用；通过体外感觉神经元和背根神经节(DRG)原代培养和体内大鼠脊髓背根损伤(DRI)模型，研究肽配体对感觉神经元轴突生长、再生和行为恢复的影响；通过表面等离子体共振（SPR）和液相色谱-质谱（LC-MS）/MS）对与其他膜受体结合的肽配体进行了表征；磷酸化蛋白质组学分析了主要受肽配体影响的细胞内信号通路，并使用特异性抑制剂验证了相关通路。
结果：研究鉴定了一种新的FGFR靶向小肽CH02，含七个氨基酸残基。CH02通过与FGFR细胞外段的高亲和力结合激活FGFR信号，并与包括VEGFR2在内的多个受体酪氨酸激酶（RTK）家族成员具有亲和力；在体外培养的感觉神经元中，CH02能维持神经元的存活并促进轴突生长；同时，CH02增强了大鼠DRI后的神经再生和感觉-运动行为恢复；CH02诱导的FGFR信号激活主要通过FGFR下游的AKT和ERK信号促进神经再生；AKT信号下游mTOR的激活增强了轴突生长潜能。
结论：本研究揭示了CH02增强神经再生的显著疗效，并提出了治疗周围神经和中枢神经系统损伤的策略。
外文摘要：Background: Fibroblast growth factor receptors (FGFRs) are key targets for nerve regeneration and repair. The therapeutic effect of exogenous recombinant FGFs in vivo is limited due to their high molecular weight. Small peptides with low molecular weight, easy diffusion, low immunogenicity, and nontoxic metabolite formation are potential candidates. The present study aimed to develop a novel low-molecular-weight peptide agonist of FGFR to promote nerve injury repair.
   Methods: Phage display technology was employed to screen peptide ligands targeting FGFR2. The peptide ligand affinity for FGFRs was detected by isothermal titration calorimetry. Structural biology-based computer virtual analysis was used to characterize the interaction between the peptide ligand and FGFR2. The peptide ligand effect on axon growth, regeneration, and behavioral recovery of sensory neurons was determined in the primary culture of sensory neurons and dorsal root ganglia (DRG) explants in vitro and a rat spinal dorsal root injury (DRI) model in vivo. The peptide ligand binding to other membrane receptors was characterized by surface plasmon resonance (SPR) and liquid chromatography-mass spectrometry (LC-MS)/MS. Intracellular signaling pathways primarily affected by the peptide ligand were characterized by phosphoproteomics, and related pathways were verified using specific inhibitors.
   Results: We identified a novel FGFR-targeting small peptide, CH02, with seven amino acid residues. CH02 activated FGFR signaling through high-affinity binding with the extracellular segment of FGFRs and also had an affinity for several receptor tyrosine kinase (RTK) family members, including VEGFR2. In sensory neurons cultured in vitro, CH02 maintained the survival of neurons and promoted axon growth. Simultaneously, CH02 robustly enhanced nerve regeneration and sensory-motor behavioral recovery after DRI in rats. CH02-induced activation of FGFR signaling promoted nerve regeneration primarily via AKT and ERK signaling downstream of FGFRs. Activation of mTOR downstream of AKT signaling augmented axon growth potential in response to CH02.
   Conclusion: Our study revealed the significant therapeutic effect of CH02 on strengthening nerve regeneration and suggested a strategy for treating peripheral and central nervous system injuries.
外文关键词：Peptides；Fibroblast growth factor receptor；Dorsal root ganglia；Nerve regeneration；Dorsal root crush injury
作者：Zhao, Y；Wang, Q；Xie, C；Cai, YL；Chen, X；Hou, YH；He, L；Li, JP；Yao, M；Chen, SX；Wu, WT；Chen, XJ；Hong, A
作者单位：Jinan Univ；Guangdong Prov Key Lab Bioengn Med；Guangdong Prov Biotechnol Drug & Engn Technol Res；Natl Engn Res Ctr Genet Med；Shenzhen Univ
期刊名称：THERANOSTICS
期刊影响因子：8.579
出版年份：2021
出版刊次：20
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