Department of Nuclear Medicine, College of Medicine, Seoul National University Hospital, 28 Yongon-Dong, Jongno-Gu, Seoul 110-744, Republic of Korea.
Biomaterials. 2011 Jul;32(21):4968-75. doi: 10.1016/j.biomaterials.2011.03.047. Epub 2011 Apr 13.
Recent advances in efficient microRNA (miRNA) delivery techniques using brain-targeted nanoparticles offer critical information for understanding the functional role of miRNAs in vivo, and for supporting targeted gene therapy in terms of treating miRNA-associated neurological diseases. Here, we report the rabies virus glycoprotein (RVG)-labeled non-toxic SSPEI nanomaterials capable of neuron-specific miR-124a delivery to neuron in vivo. The RVG-labeled BPEI-SS (RVG-SSPEI) nanocarrier showed less toxicity in acetylcholine receptor-positive Neuro2a cells, and electrostatic interaction of RVG-SSPEI with miR-124a exhibited optimal transfection efficacy. The RVG-SSPEI polymer specifically targeted Neuro2a using cy5.5-miR-124a mixed with RVG-SSPEI. The functional action of miR-124a oligomers released from polyplexes in the cytoplasmic region was evaluated by a reporter vector containing a miR-124a -binding sequence, and showed a significantly reduced reporter signal in a dose-dependent manner. Cy5.5-miR-124a/RVG-SSPEI- injected into mice via tail veins displayed the enhanced accumulation of miR-124a in the isolated brain. Hindrance of the efficient penetration of neuronal cells by size limitation of the miR-124a/RVG-SSPEI improved with the help of mannitol through blood-brain barrier disruption. These findings indicated that the RVG peptide combined with mannitol infusion using SSPEI polymer for neuron-specific targeting in vivo is sufficient to deliver neurogenic microRNA into the brain.
最近利用靶向脑的纳米颗粒高效传递 microRNA（miRNA）的技术进展为理解 miRNA 在体内的功能作用提供了关键信息，并为支持针对 miRNA 相关神经疾病的靶向基因治疗提供了支持。在这里，我们报告了狂犬病病毒糖蛋白（RVG）标记的无毒 SSPEI 纳米材料，能够将神经元特异性 miR-124a 递送到体内神经元。RVG 标记的 BPEI-SS（RVG-SSPEI）纳米载体在乙酰胆碱受体阳性的 Neuro2a 细胞中显示出较低的毒性，并且 RVG-SSPEI 与 miR-124a 的静电相互作用表现出最佳的转染效率。RVG-SSPEI 聚合物通过与 RVG-SSPEI 混合的 cy5.5-miR-124a 特异性靶向 Neuro2a。通过含有 miR-124a 结合序列的报告载体评估了从质体中释放的 miR-124a 寡聚物的功能作用，并且以剂量依赖性方式显示出显著降低的报告信号。通过尾巴静脉将 Cy5.5-miR-124a/RVG-SSPEI 注射到小鼠体内，显示出 miR-124a 在分离的大脑中的积累增强。miR-124a/RVG-SSPEI 的有效穿透神经元细胞的阻碍由于其大小限制而受到阻碍，通过血脑屏障破坏用甘露醇辅助得到改善。这些发现表明，RVG 肽与 SSPEI 聚合物结合使用甘露醇进行体内神经元特异性靶向足以将神经发生 miRNA 递送到大脑中。
