Chung Chiu-Yen, Lin Martin Hsiu-Chu, Lee I-Neng, Lee Tsong-Hai, Lee Ming-Hsueh, Yang Jen-Tsung
Department of Neurosurgery, Chang Gung Memorial Hospital, Chia-Yi 61363, Taiwan.
Department of Medical Research, Chang Gung Memorial Hospital, Chia-Yi 61363, Taiwan.
Int J Mol Sci. 2017 Mar 19;18(3):663. doi: 10.3390/ijms18030663.
Brain derived neurotrophic factor (BDNF) can induce neural differentiation in stem cells and has the potential for repair of the nervous system. In this study, a polysorbate 80-coated polybutylcyanoacrylate nanocarrier (PS80 PBCA NC) was constructed to deliver plasmid DNAs (DNAs) containing BDNF gene attached to a hypoxia-responsive element (HRE-cmvBDNF). The hypoxia-sensing mechanism of BDNF expression and inductiveness of the nano-formulation on mouse induced pluripotent stem cells (iPSCs) to differentiate into neurons following hypoxia was tested in vitro with immunofluorescent staining and Western blotting. The HRE-cmvBDNF appeared to adsorb onto the surface of PS80 PBCA NC, with a resultant mean diameter of 92.6 ± 1.0 nm and zeta potential of -14.1 ± 1.1 mV. HIF-1α level in iPSCs was significantly higher in hypoxia, which resulted in a 51% greater BDNF expression when transfected with PS80 PBCA NC/HRE-cmvBDNF than those without hypoxia. TrkB and phospho-Akt were also elevated which correlated with neural differentiation. The findings suggest that PS80 PBCA NC too can be endocytosed to serve as an efficient vector for genes coupled to the HRE in hypoxia-sensitive cells, and activation of the PI3/Akt pathway in iPSCs by BDNF is capable of neural lineage specification.
脑源性神经营养因子(BDNF)可诱导干细胞发生神经分化,具有修复神经系统的潜力。在本研究中,构建了一种聚山梨酯80包被的聚氰基丙烯酸正丁酯纳米载体(PS80 PBCA NC),用于递送含有与缺氧反应元件(HRE-cmvBDNF)连接的BDNF基因的质粒DNA(DNA)。通过免疫荧光染色和蛋白质印迹法在体外测试了BDNF表达的缺氧传感机制以及该纳米制剂在缺氧后对小鼠诱导多能干细胞(iPSC)分化为神经元的诱导作用。HRE-cmvBDNF似乎吸附在PS80 PBCA NC的表面,其平均直径为92.6±1.0 nm,zeta电位为-14.1±1.1 mV。缺氧时iPSC中的HIF-1α水平显著升高,这导致用PS80 PBCA NC/HRE-cmvBDNF转染时BDNF表达比无缺氧时高51%。TrkB和磷酸化Akt也升高,这与神经分化相关。研究结果表明,PS80 PBCA NC也可被内吞,作为缺氧敏感细胞中与HRE偶联基因的有效载体,并且BDNF激活iPSC中的PI3/Akt途径能够促进神经谱系定向分化。