PDF(Pubmed)
Abstract：
Introduction: Blood-brain barrier with strictly controlled activity participates in a coordinated transfer of bioactive molecules from the blood to the brain. Among different delivery approaches, gene delivery is touted as a promising strategy for the treatment of several nervous system disorders. The transfer of exogenous genetic elements is limited by the paucity of suitable carriers. As a correlate, designing high-efficiency biocarriers for gene delivery is challenging. This study aimed to deliver pEGFP-N1 plasmid into the brain parenchyma using CDX-modified chitosan (CS) nanoparticles (NPs). Methods: Herein, we attached CDX, a 16 amino acids peptide, to the CS polymer using bifunctional polyethylene glycol (PEG) formulated with sodium tripolyphosphate (TPP), by ionic gelation method. Developed NPs and their nanocomplexes with pEGFP-N1 (CS-PEG-CDX/pEGFP) were characterized using DLS, NMR, FTIR, and TEM analyses. For in vitro assays, a rat C6 glioma cell line was used for cell internalization efficiency. The biodistribution and brain localization of nanocomplexes were studied in a mouse model after intraperitoneal injection using in vivo imaging and fluorescent microscopy. Results: Our results showed that CS-PEG-CDX/pEGFP NPs were uptaken by glioma cells in a dose-dependent manner. In vivo imaging revealed successful entry into the brain parenchyma indicated with the expression of green fluorescent protein (GFP) as a reporter protein. However, the biodistribution of developed NPs was also evident in other organs especially the spleen, liver, heart, and kidneys. Conclusion: Based on our results, CS-PEG-CDX NPs can provide a safe and effective nanocarrier for brain gene delivery into the central nervous system (CNS).
摘要：
简介：具有严格控制活性的血脑屏障参与生物活性分子从血液到大脑的协调转移。在不同的交付方式中，基因传递被吹捧为治疗几种神经系统疾病的有希望的策略。外源遗传元件的转移受到缺乏合适载体的限制。作为相关的，设计用于基因传递的高效生物载体具有挑战性。本研究旨在使用CDX修饰的壳聚糖（CS）纳米颗粒（NP）将pEGFP-N1质粒递送到脑实质中。方法：这里，我们附上了CDX，16个氨基酸的肽，CS聚合物使用双官能聚乙二醇（PEG）与三磷酸钠（TPP）配制，采用离子凝胶法。使用DLS表征开发的NP及其与pEGFP-N1（CS-PEG-CDX/pEGFP）的纳米复合物，NMR,FTIR,和TEM分析。对于体外测定，大鼠C6神经胶质瘤细胞系用于细胞内化效率。使用体内成像和荧光显微镜在腹膜内注射后的小鼠模型中研究了纳米复合物的生物分布和脑定位。结果：我们的结果表明，胶质瘤细胞以剂量依赖的方式摄取CS-PEG-CDX/pEGFPNPs。体内成像显示成功进入脑实质，表明绿色荧光蛋白（GFP）作为报告蛋白的表达。然而,发育的NPs的生物分布在其他器官尤其是脾脏中也很明显，肝脏,心,还有肾脏.结论：根据我们的结果，CS-PEG-CDXNP可以为大脑基因递送到中枢神经系统(CNS)提供安全有效的纳米载体。
