Peng Jin, Pan Qian, Zhang Wei, Yang Hao, Zhou Xue, Jiang Hua
West China School of Preclinical and Forensic Medicine, Sichuan University, Chengdu, Sichuan Province, People's Republic of China; Metabonomics and Multidisciplinary Laboratory for Trauma Research, Sichuan Provincial People's Hospital, Sichuan Academy of Medical Sciences, Chengdu, Sichuan Province, People's Republic of China.
J Biomed Mater Res A. 2014 Jul;102(7):2157-62. doi: 10.1002/jbm.a.34892. Epub 2013 Aug 7.
Dermatan sulfate is widely distributed as glycosaminoglycan side chains of proteoglycans, which are the main components of glial scar and inhibit neurite regeneration after nerve injury. However its role in the inhibiting process is not clear. Understanding neurite extension in three-dimensional scaffolds is critical for neural tissue engineering. This study used agarose gels modified with dermatan sulfate as the three-dimensional culture scaffold. We explored structure-function relationship between the three-dimensional scaffold and neurite extension and examined the role of dermatan sulfate on neurite extension in the three-dimensional scaffold. A range of agarose concentrations was used to generate varied gel physical structures and the corresponding neurite extension of embryonic day (E9) chick dorsal root ganglia was examined. We measured gel stiffness and gel pore size to determine whether dermatan sulfate changed the gels' conformation. As gel concentration increased, neurite length and gel pore size decreased, and gel stiffness increased. At 1.00 and 1.25% (wt/vol) concentrations, dermatan sulfates both immobilized with agarose gels and dissolved in culture medium inhibit neurite extension. While at 1.50 and 1.75% (wt/vol) concentrations, only immobilized dermatan sulfate worked. Immobilized dermatan sulfate could modify molecular shape of agarose gels, decrease gel pore size statistically, but did not influence gel stiffness. We have proved that the decrease of gel pore size is insufficient to inhibit neurite extension. These results indicate that dermatan sulfate inhibits neurite extension not through forming a mechanical barrier. Maybe its interaction with neuron membrane is the key factor in neurite extension.
硫酸皮肤素作为蛋白聚糖的糖胺聚糖侧链广泛分布，蛋白聚糖是胶质瘢痕的主要成分，并且在神经损伤后抑制神经突再生。然而，其在抑制过程中的作用尚不清楚。了解神经突在三维支架中的延伸对于神经组织工程至关重要。本研究使用用硫酸皮肤素修饰的琼脂糖凝胶作为三维培养支架。我们探讨了三维支架与神经突延伸之间的结构 - 功能关系，并研究了硫酸皮肤素在三维支架中对神经突延伸的作用。使用一系列琼脂糖浓度来产生不同的凝胶物理结构，并检测胚胎第9天（E9）鸡背根神经节相应的神经突延伸情况。我们测量了凝胶硬度和凝胶孔径，以确定硫酸皮肤素是否改变了凝胶的构象。随着凝胶浓度增加，神经突长度和凝胶孔径减小，而凝胶硬度增加。在1.00%和1.25%（重量/体积）浓度下，与琼脂糖凝胶固定以及溶解在培养基中的硫酸皮肤素均抑制神经突延伸。而在1.50%和1.75%（重量/体积）浓度下，只有固定化的硫酸皮肤素起作用。固定化的硫酸皮肤素可以改变琼脂糖凝胶的分子形状，统计学上减小凝胶孔径，但不影响凝胶硬度。我们已经证明凝胶孔径的减小不足以抑制神经突延伸。这些结果表明，硫酸皮肤素不是通过形成机械屏障来抑制神经突延伸。也许其与神经元膜的相互作用是神经突延伸中的关键因素。
