中国神经再生研究(英文版) ›› 2017, Vol. 12 ›› Issue (5): 687-691.doi: 10.4103/1673-5374.206630

• 综述:神经损伤修复保护与再生 • 上一篇    下一篇

通过硫酸软骨素蛋白聚糖抑制和增强神经再生

  

  • 收稿日期:2017-05-09 出版日期:2017-05-15 发布日期:2017-05-15
  • 基金资助:

     

    本文的研究得到了芬兰创新基金会,芬兰科学院和西格里•朱塞利斯基金会的支持

Inhibition and enhancement of neural regeneration by chondroitin sulfate proteoglycans

Heikki Rauvala1, Mikhail Paveliev1, Juha Kuja-Panula1, Natalia Kulesskaya1, 2   

  1. 1 Neuroscience Center, University of Helsinki, Helsinki, Finland; 2 Department of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
  • Received:2017-05-09 Online:2017-05-15 Published:2017-05-15
  • Contact: Heikki Rauvala, Ph.D., heikki.rauvala@helsinki.fi.
  • Supported by:

    Our studies have been supported by the Finnish Funding Agency for Innovation Tekes, Academy of Finland and the Sigrid Jusélius Foundation.

摘要:

目前神经再生研究中的教条表示,硫酸软骨素(CS)聚糖链抑制成人中枢神经系统(CNS)的可塑性和再生。基于我们最近的研究,我们认为CS链的作用取决于发展表达的CS结合因子,其能够逆转CS聚糖链对神经突向外生长的抑制。我们已经将我们的研究集中在肝素结合生长相关分子(HB-GAM;也称为多潜养蛋白)作为可能克服神经突生长和再生的CS抑制的候选分子,因为HB-GAM在早期出生后的啮齿动物脑中高度表达,并且对应于幼年脑的可塑性升高,可以迅速与CS链结合,增强CNS神经元的神经突生长。文中的体外研究表明,涂有硫酸软骨素蛋白聚糖(CSPG)的底物可以极大地抑制CNS神经元的神经突生长。然而,当将HB-GAM以类似于在幼年脑中发现的浓度加入到培养基中时,CSPG抑制神经突向外生长被逆转以促进神经突生长。对神经突生长的增强作用取决于底物的CS链,因为在普通培养孔或用软骨素酶ABC处理的CSPG底物上没有观察到在可溶性HB-GAM存在下对神经突生长的增强作用。我们的体内研究与体外研究一致,当HB-GAM局部注射到创伤部位时,揭示了脑脊液损伤后脊髓再刺激后树突再生的增强,和脊髓横断损伤后轴突再生的增强。我们建议建立一种模型,HB-GAM注射到创伤区或从活化星形胶质细胞分泌的模型结合富含CSPG的基质,如胶质瘢痕,所得的HB-GAM/CS复合物通过结合磷脂酰肌醇蛋白聚糖诱导神经突生长-2的神经元表面。此外,HB-GAM掩盖了神经突生长抑制受体蛋白酪氨酸磷酸酶(PTPσ)的CS结合位点,这可能有助于HB-GAM诱导再生作用。对HB-GAM/CS机制的研究预计将为脑和脊髓损伤药物开发铺平道路。

ORCID:0000-0001-7809-9811(Heikki Rauvala)

Abstract:

The current dogma in neural regeneration research implies that chondroitin sulfate proteoglycans (CSPGs) inhibit plasticity and regeneration in the adult central nervous system (CNS). We argue that the role of the CSPGs can be reversed from inhibition to activation by developmentally expressed CSPG-binding factors. Heparin-binding growth-associated molecule (HB-GAM; also designated as pleiotrophin) has been studied as a candidate molecule that might modulate the role of CSPG matrices in plasticity and regeneration. Studies in vitro show that in the presence of soluble HB-GAM chondroitin sulfate (CS) chains of CSPGs display an enhancing effect on neurite outgrowth. Based on the in vitro studies, we suggest a model according to which the HB-GAM/CS complex binds to the neuron surface receptor glypican-2, which induces neurite growth. Furthermore, HB-GAM masks the CS binding sites of the neurite outgrowth inhibiting receptor protein tyrosine phosphatase sigma (PTPσ), which may contribute to the HB-GAM-induced regenerative effect. In vivo studies using two-photon imaging after local HB-GAM injection into prick-injury of the cerebral cortex reveal regeneration of dendrites that has not been previously demonstrated after injuries of the mammalian nervous system. In the spinal cord, two-photon imaging displays HB-GAM-induced axonal regeneration. Studies on the HB-GAM/CS mechanism in vitro and in vivo are expected to pave the way for drug development for injuries of brain and spinal cord.

Key words: CNS injury, axon regeneration, dendrite regeneration, proteoglycans, aggrecan, glypican, HB-GAM, pleiotrophin, PTEN