Wuya College of Innovation, Shenyang Pharmaceutical University, Wenhua Road No. 103, Shenyang 110016, People's Republic of China.
Drug Discovery Pipeline, Hefei Institute of Stem Cell and Regenerative Medicine, Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences, Guangzhou 510530, People's Republic of China.
ACS Appl Mater Interfaces. 2021 Jan 27;13(3):3722-3737. doi: 10.1021/acsami.0c21259. Epub 2021 Jan 13.
Pulmonary delivery of small interfering RNA (siRNA)-based drugs is promising in treating severe lung disorders characterized by the upregulated expression of disease-causing genes. Previous studies have shown that the sustained siRNA release can be achieved from polymeric matrix nanoparticles based on poly(lactide--glycolide) (PLGA) loaded with lipoplexes (LPXs) composed of cationic lipid and anionic siRNA (lipid-polymer hybrid nanoparticles, LPNs). Yet, the efficacy, potential for prolonging the pharmacological effect, disposition, and safety of LPNs after pulmonary administration have not been investigated. In this study, siRNA against enhanced green fluorescent protein (EGFP-siRNA) was either assembled with 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) to form LPX or co-entrapped with DOTAP in PLGA nanoparticles to form LPNs. The disposition and clearance of LPXs and LPNs in mouse lungs were studied after intratracheal administration by using single-photon emission computed tomography/computed tomography (SPECT/CT) and gamma counting. Fluorescence spectroscopy, Western blot, and confocal laser scanning microscopy were used to evaluate the silencing of the EGFP expression mediated by the LPXs and LPNs after intratracheal administration to transgenic mice expressing the EGFP gene. The biocompatibility of LPXs and LPNs was investigated by measuring the cytokine level, total cell counts in bronchoalveolar lavage fluid, and observing the lung tissue histology section. The results showed that the silencing of the EGFP expression mediated by LPNs after pulmonary administration was both prolonged and enhanced as compared to LPXs. This may be attributed to the sustained release characteristics of PLGA, and the prolonged retention in the lung tissue of the colloidally more stable LPNs in comparison to LPXs, as indicated by SPECT/CT. The presence of PLGA effectively alleviated the acute inflammatory effect of cationic lipids to the lungs. This study suggests that PLGA-based LPNs may present an effective formulation strategy to mediate sustained gene silencing effects in the lung pulmonary administration.
肺部递送基于小干扰 RNA（siRNA）的药物在治疗以致病基因表达上调为特征的严重肺部疾病方面具有广阔的前景。先前的研究表明，基于聚（乳酸-共-乙醇酸）（PLGA）的聚合物基质纳米粒可实现 siRNA 的持续释放，该纳米粒负载由阳离子脂质和阴离子 siRNA 组成的脂质体（LPX）（脂质-聚合物混合纳米粒，LPNs）。然而，尚未研究 LPNs 肺部给药后的疗效、延长药效的潜力、处置和安全性。在这项研究中，针对增强型绿色荧光蛋白（EGFP-siRNA）的 siRNA 与 1,2-二油酰基-3-三甲铵丙烷（DOTAP）组装形成 LPX，或者与 DOTAP 共包封在 PLGA 纳米粒中形成 LPNs。通过单光子发射计算机断层扫描/计算机断层扫描（SPECT/CT）和伽马计数研究了 LPX 和 LPNs 在气管内给药后在小鼠肺部的分布和清除。荧光光谱、Western blot 和共聚焦激光扫描显微镜用于评估 LPX 和 LPNs 经气管内给药后转染 EGFP 基因的转基因小鼠中 EGFP 表达的沉默情况。通过测量支气管肺泡灌洗液中的细胞因子水平、总细胞计数以及观察肺组织组织学切片来研究 LPX 和 LPNs 的生物相容性。结果表明，与 LPX 相比，LPNs 肺部给药后介导的 EGFP 表达沉默作用既延长又增强。这可能归因于 PLGA 的持续释放特性，以及与 LPX 相比，胶体更稳定的 LPNs 在肺组织中的滞留时间延长，这一点通过 SPECT/CT 得到证实。PLGA 的存在有效地减轻了阳离子脂质对肺部的急性炎症作用。本研究表明，PLGA 基 LPNs 可能为肺部给药介导持续的基因沉默效果提供一种有效的制剂策略。
