State Key Laboratory of Genetic Engineering Department of Pharmaceutical Sciences, School of Life Sciences, Fudan University, Shanghai, 200433, China.
Pharm Res. 2013 Oct;30(10):2596-606. doi: 10.1007/s11095-013-1086-4. Epub 2013 May 29.
The lack of effective delivery vehicles impedes in vivo applications of siRNA. The trimethyl chitosan-cysteine (TC) nanoparticles (NPs) were developed for in vivo delivery of tumor necrosis factor α (TNF-α) siRNA via oral gavage and intraperitoneal injection.
The nanoparticles formulated from TC conjugate of 100, 200, and 500 kDa were prepared through ionic gelation with sodium tripolyphosphate, termed as TC100 NPs, TC200 NPs, and TC500 NPs, respectively. They were evaluated in terms of stability, siRNA protection, cellular uptake and TNF-α knockdown in peritoneal exudates macrophage cells (PECs), and in vivo TNF-α silencing in acute hepatic injury mice.
TC100 NPs exhibited poor stability in simulated physiological environment compared to TC200 NPs and TC500 NPs. Compared to TC500 NPs, TC200 NPs could significantly enhance in vitro and in vivo cellular uptake by PECs and facilitate cytoplasmic siRNA release, resulting in high in vitro and in vivo TNF-α knockdown. Superior TNF-α suppressing level was obtained with TC200 NPs via oral gavage rather than intraperitoneal injection.
The efficacies of in vivo TNF-α silencing were related to the molecular weight of TC conjugate and the administration route, which would assist in the rational design of siRNA vehicles.
有效的递药载体的缺乏阻碍了 siRNA 的体内应用。本研究开发了三甲基壳聚糖-半胱氨酸（TC）纳米粒（NPs），通过口服灌胃和腹腔注射递送至体内的肿瘤坏死因子α（TNF-α）siRNA。
通过与 100、200 和 500 kDa 的 TC 缀合物的离子凝胶作用制备纳米粒，分别命名为 TC100 NPs、TC200 NPs 和 TC500 NPs。评价了其在模拟生理环境下的稳定性、siRNA 保护、细胞摄取和腹腔渗出巨噬细胞（PECs）中的 TNF-α 敲低作用，以及急性肝损伤小鼠中的体内 TNF-α 沉默作用。
与 TC200 NPs 和 TC500 NPs 相比，TC100 NPs 在模拟生理环境下表现出较差的稳定性。与 TC500 NPs 相比，TC200 NPs 可显著增强 PECs 的体外和体内细胞摄取，并促进细胞质中 siRNA 的释放，从而实现高体外和体内 TNF-α 敲低。通过口服灌胃而非腹腔注射，TC200 NPs 可获得更好的 TNF-α 抑制水平。
体内 TNF-α 沉默的疗效与 TC 缀合物的分子量和给药途径有关，这将有助于合理设计 siRNA 载体。
