Hayashi Noriko, Miyata Seiji, Kariya Yutaka, Takano Ryo, Hara Saburo, Kamei Kaeko
Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan.
Neurosci Res. 2004 May;49(1):19-27. doi: 10.1016/j.neures.2004.01.007.
Injury to the central nervous system causes glial reactions, which eventually lead to the formation of a glial scar and inhibit axonal regeneration. The present study aimed to reduce the extent of glial scar formation in injured cerebral cortex using heparin hexasaccharide (6-mer) and octasaccharide (8-mer). A single injection of 20 microl of heparin 6-mer or heparin 8-mer (10mg/ml), native heparin (10mg/ml), or saline vehicle was given into the wound cavity just after cryo-injury in the cerebral cortex. In saline-injected control rats, strong chondroitin sulfate-A (CS-A) immunoreactivity using 2H6 antibody was observed around the injured site. Double labeling using an antibody against glial fibrillary acidic protein, a glial marker, further demonstrated that CS-A immunoreactivity was mainly expressed on the reactive astrocytes at the glial scar, indicating that CS-A immunohistochemistry is useful for evaluating glial scar formation. Quantitative morphometrical analysis revealed that the area of CS-A immunoreactivity was significantly decreased by 53% in heparin-6-mer-injected animals and 44% in heparin-8-mer-injected ones 6 days after the injury, but native heparin had no effect on CS-A-immunoreactive areas. Both heparin oligosaccharides also attenuated the intensity of CS-A immunoreactivity in the reactive astrocytes and caused astrocytic cellular processes to be less branched. These results demonstrate that a single injection of heparin oligosaccharides attenuates glial scar formation, indicating that heparin oligosaccharides may be applicable to many fibrotic diseases and restore functional integrity.
中枢神经系统损伤会引发胶质反应，最终导致胶质瘢痕形成并抑制轴突再生。本研究旨在使用肝素六糖（6-聚体）和八糖（8-聚体）减少受损大脑皮质中胶质瘢痕的形成程度。在大脑皮质冷冻损伤后，立即向伤口腔内单次注射20微升肝素6-聚体或肝素8-聚体（10毫克/毫升）、天然肝素（10毫克/毫升）或生理盐水。在注射生理盐水的对照大鼠中，在损伤部位周围观察到使用2H6抗体的强硫酸软骨素A（CS-A）免疫反应性。使用针对胶质纤维酸性蛋白（一种胶质标志物）的抗体进行双重标记，进一步证明CS-A免疫反应性主要在胶质瘢痕处的反应性星形胶质细胞上表达，表明CS-A免疫组织化学可用于评估胶质瘢痕形成。定量形态计量分析显示，损伤6天后，注射肝素6-聚体的动物中CS-A免疫反应性区域显著减少53%，注射肝素8-聚体的动物中减少44%，但天然肝素对CS-A免疫反应性区域没有影响。两种肝素寡糖还减弱了反应性星形胶质细胞中CS-A免疫反应性的强度，并使星形胶质细胞的细胞突起分支减少。这些结果表明，单次注射肝素寡糖可减轻胶质瘢痕形成，表明肝素寡糖可能适用于许多纤维化疾病并恢复功能完整性。
