Elsabahy Mahmoud, Zhang Mingzhen, Gan Shao-Ming, Waldron Karen C, Leroux Jean-Christophe
Faculty of Pharmacy, University of Montreal, C.P. 6128, Succursale Centre-Ville, Montreal (QC) H3C 3J7, Canada.
Department of Chemistry, University of Montreal, C.P. 6128, Succursale Centre-Ville, Montreal (QC) H3C 3J7, Canada.
Soft Matter. 2008 Jan 22;4(2):294-302. doi: 10.1039/b714221h.
The objectives of the current study were to design and characterize poly(ethylene glycol) (PEG)-based carriers for antisense oligonucleotide (AON) delivery that would gradually release the AON upon the enzymatic degradation of a complementary nuclease-sensitive sequence (SON). A phosphodiester SON was conjugated to one extremity or to the central part of PEG (molecular weight 10 or 20 K). The PEG-SON was hybridized to a nuclease-resistant phosphorothioate AON analog. Compared to the non-PEGylated duplex, the PEG-SON/AON derivative had a modest impact on the degradation kinetics of SON as monitored by a fluorescence dequenching assay performed in the presence of DNase 1. The reaction rate depended on the grafting position of SON and on the PEG's molecular weight. To further control the release rate, PEG-SON/AON conjugates were complexed to poly(amidoamine) (PAMAM) dendrimers of different generations (G). Interaction with PAMAMs of G3 and G5 yielded monodisperse polyion complex micelles (PICMs) with average mean sizes ranging from 70 to 100 nm. The PICMs were found to decrease the catalytic reaction rate by 20 to 100 fold; the slowest release kinetics being achieved with PEG10K-SON/AON/G5 PAMAM. The PEGylated conjugates reported in this manuscript as well as their self-assemblies with PAMAMs, could prove potentially useful to confer prolonged circulating properties to nucleic acid drugs and release them in a sustained manner.
本研究的目的是设计并表征基于聚乙二醇（PEG）的反义寡核苷酸（AON）递送载体，该载体在互补核酸酶敏感序列（SON）发生酶促降解时能逐渐释放AON。将磷酸二酯SON连接到PEG（分子量为10或20K）的一端或中央部分。将PEG-SON与耐核酸酶的硫代磷酸酯AON类似物杂交。与未PEG化的双链体相比，通过在DNase 1存在下进行的荧光猝灭测定监测，PEG-SON/AON衍生物对SON的降解动力学有适度影响。反应速率取决于SON的接枝位置和PEG的分子量。为了进一步控制释放速率，将PEG-SON/AON缀合物与不同代数（G）的聚（酰胺胺）（PAMAM）树枝状大分子复合。与G3和G5的PAMAM相互作用产生平均尺寸范围为70至100nm的单分散聚离子复合胶束（PICM）。发现PICM可使催化反应速率降低20至100倍；使用PEG10K-SON/AON/G5 PAMAM实现最慢的释放动力学。本手稿中报道的PEG化缀合物及其与PAMAM的自组装，可能证明对赋予核酸药物延长的循环特性并以持续方式释放它们具有潜在的用途。
