Lin Chia-Yu, Luo Shyh-Chyang, Yu Jia-Shing, Chen Ta-Ching, Su Wei-Fang
Department of Materials Science and Engineering, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei 10617, Taiwan.
Molecular Imaging Center, National Taiwan University, Taipei 10617, Taiwan.
ACS Appl Bio Mater. 2019 Jan 22;2(1):518-526. doi: 10.1021/acsabm.8b00697. Epub 2018 Dec 21.
Neural tissue engineering has emerged as a promising technology to cure neural damages. Although various synthetic polymers with good biocompatibility and biodegradability have been adopted as candidate materials for scaffolds, most of them require the incorporation of biomolecules or conductive materials to promote the growth of long axons. Herein we demonstrate for the first time a unique peptide-based polyelectrolyte that is ionically conductive and contains a neurotransmitter, glutamic acid. The designed polymer, sodium salt of poly(γ-benzyl-l-glutamate)--poly(l-glutamic acid) (PBGA20-Na), was synthesized and fabricated into a 3D fibrous scaffold with aligned fibers. Neuron-like rat pheochromocytoma (PC12) cells were cultured on the scaffolds to evaluate cell proliferation and differentiation with or without electrical stimulation. The results show that with both electrical and biochemical cues presented in the polyelectrolyte, PBGA20-Na promotes longer neurite outgrowth compared with the neutral poly(γ-benzyl-l-glutamate) (PBG) and the poly(γ-benzyl-l-glutamate)--poly(l-glutamic acid) (PBGA20). Furthermore, the neurite length of the cells cultured on PBGA20-Na is more than twice as long compared with the conventional biopolymer, polycaprolactone. In conclusion, PBGA20-Na is a promising biomaterial for neural tissue engineering and drug-screening platforms.
神经组织工程已成为一种治疗神经损伤的有前景的技术。尽管各种具有良好生物相容性和生物降解性的合成聚合物已被用作支架的候选材料，但其中大多数需要加入生物分子或导电材料以促进长轴突的生长。在此，我们首次展示了一种独特的基于肽的聚电解质，它具有离子导电性且含有神经递质谷氨酸。所设计的聚合物，聚（γ-苄基-L-谷氨酸）-聚（L-谷氨酸）钠盐（PBGA20-Na），被合成并制成具有排列纤维的三维纤维支架。将神经元样大鼠嗜铬细胞瘤（PC12）细胞培养在支架上，以评估在有或没有电刺激的情况下细胞的增殖和分化。结果表明，在聚电解质中同时存在电和生化信号时，与中性聚（γ-苄基-L-谷氨酸）（PBG）和聚（γ-苄基-L-谷氨酸）-聚（L-谷氨酸）（PBGA20）相比，PBGA20-Na能促进更长的神经突生长。此外，与传统生物聚合物聚己内酯相比，在PBGA20-Na上培养的细胞的神经突长度是其两倍多。总之，PBGA20-Na是一种用于神经组织工程和药物筛选平台的有前景的生物材料。
