UNAM-Institute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800, Turkey.
Biomacromolecules. 2011 Aug 8;12(8):3007-14. doi: 10.1021/bm200641e. Epub 2011 Jul 7.
Antisense oligonucleotides provide a promising therapeutic approach for several disorders including cancer. Chemical stability, controlled release, and intracellular delivery are crucial factors determining their efficacy. Gels composed of nanofibrous peptide network have been previously suggested as carriers for controlled delivery of drugs to improve stability and to provide controlled release, but have not been used for oligonucleotide delivery. In this work, a self-assembled peptide nanofibrous system is formed by mixing a cationic peptide amphiphile (PA) with Bcl-2 antisense oligodeoxynucleotide (ODN), G3139, through electrostatic interactions. The self-assembly of PA-ODN gel was characterized by circular dichroism, rheology, atomic force microscopy (AFM) and scanning electron microscopy (SEM). AFM and SEM images revealed establishment of the nanofibrous PA-ODN network. Due to the electrostatic interactions between PA and ODN, ODN release can be controlled by changing PA and ODN concentrations in the PA-ODN gel. Cellular delivery of the ODN by PA-ODN nanofiber complex was observed by using fluorescently labeled ODN molecule. Cells incubated with PA-ODN complex had enhanced cellular uptake compared to cells incubated with naked ODN. Furthermore, Bcl-2 mRNA amounts were lower in MCF-7 human breast cancer cells in the presence of PA-ODN complex compared to naked ODN and mismatch ODN evidenced by quantitative RT-PCR studies. These results suggest that PA molecules can control ODN release, enhance cellular uptake and present a novel efficient approach for gene therapy studies and oligonucleotide based drug delivery.
反义寡核苷酸为包括癌症在内的多种疾病提供了一种很有前途的治疗方法。化学稳定性、控制释放和细胞内递药是决定其疗效的关键因素。先前已经提出由纳米纤维状肽网络组成的凝胶作为药物控制递药的载体，以提高稳定性并提供控制释放，但尚未用于寡核苷酸递药。在这项工作中，通过静电相互作用将阳离子肽两亲物（PA）与 Bcl-2 反义寡脱氧核苷酸（ODN）、G3139 混合形成自组装肽纳米纤维系统。通过圆二色性、流变学、原子力显微镜（AFM）和扫描电子显微镜（SEM）对 PA-ODN 凝胶的自组装进行了表征。AFM 和 SEM 图像揭示了 PA-ODN 纳米纤维网络的建立。由于 PA 和 ODN 之间的静电相互作用，通过改变 PA-ODN 凝胶中的 PA 和 ODN 浓度，可以控制 ODN 的释放。通过使用荧光标记的 ODN 分子观察到 ODN 通过 PA-ODN 纳米纤维复合物的细胞递药。与孵育裸 ODN 的细胞相比，孵育 PA-ODN 复合物的细胞具有更高的细胞摄取。此外，通过定量 RT-PCR 研究表明，与裸 ODN 和错配 ODN 相比，PA-ODN 复合物存在时 MCF-7 人乳腺癌细胞中的 Bcl-2 mRNA 量较低。这些结果表明，PA 分子可以控制 ODN 释放、增强细胞摄取，并为基因治疗研究和基于寡核苷酸的药物递药提供一种新的有效方法。
