Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada.
Nanomedicine. 2013 Jul;9(5):665-74. doi: 10.1016/j.nano.2012.11.006. Epub 2012 Dec 6.
Gene silencing activity of lipid nanoparticle (LNP) formulations of siRNA requires LNP surface factors promoting cellular uptake. This study aimed to identify small molecules that enhance cellular uptake of LNP siRNA systems, then use them as LNP-associated ligands to improve gene silencing potency. Screening the Canadian Chemical Biology Network molecules for effects on LNP uptake into HeLa cells found that cardiac glycosides like ouabain and strophanthidin caused the highest uptake. Cardiac glycosides stimulate endocytosis on binding to plasma membrane Na(+)/K(+) ATPase found in all mammalian cells, offering the potential to stimulate LNP uptake into various cell types. A PEG-lipid containing strophanthidin at the end of PEG (STR-PEG-lipid) was synthesized and incorporated into LNP. Compared to non-liganded systems, STR-PEG-lipid enhanced LNP uptake in various cell types. Furthermore, this enhanced uptake improved marker gene silencing in vitro. Addition of STR-PEG-lipid to LNP siRNA may have general utility for enhancing gene silencing potency.
In this study, the authors identified small molecules that enhance cellular uptake of lipid nanoparticle siRNA systems, then used them as LNP-associated ligands to improve gene silencing potency.
脂质纳米颗粒（LNP）siRNA 制剂的基因沉默活性需要促进细胞摄取的 LNP 表面因素。本研究旨在鉴定能增强 LNP 摄取 siRNA 系统的小分子，然后将它们用作 LNP 相关配体来提高基因沉默效力。筛选加拿大化学生物学网络分子对 HeLa 细胞摄取 LNP 的影响，发现哇巴因和哇巴拉丁等强心苷能引起最高摄取。强心苷与所有哺乳动物细胞中存在的质膜 Na(+) / K(+) ATP 酶结合后会刺激内吞作用，这为刺激各种细胞类型摄取 LNP 提供了潜力。合成了一种在 PEG 末端含有哇巴拉丁的 PEG-脂质（STR-PEG-脂质），并将其掺入 LNP 中。与非配体系统相比，STR-PEG-脂质增强了各种细胞类型中 LNP 的摄取。此外，这种增强的摄取提高了体外标记基因的沉默。将 STR-PEG-脂质添加到 LNP siRNA 中可能对增强基因沉默效力具有普遍适用性。
在这项研究中，作者鉴定了能增强脂质纳米颗粒 siRNA 系统摄取的小分子，然后将它们用作 LNP 相关配体来提高基因沉默效力。
