Localized stimulation of angiogenesis is an attractive strategy to improve the repair of ischemic or injured tissues. Several microRNAs (miRNAs) such as miRNA-92a (miR-92a) have been reported to negatively regulate angiogenesis in ischemic disease. To exploit the clinical potential of miR-92a inhibitors, safe and efficient delivery needs to be established. Here, we used deoxycholic acid-modified polyethylenimine polymeric conjugates (PEI-DA) to deliver a locked nucleic acid (LNA)-based miR-92a inhibitor (LNA-92a) in vitro and in vivo. The positively charged PEI-DA conjugates condense the negatively charged inhibitors into nano-sized polyplexes (135 ± 7.2 nm) with a positive net charge (34.2 ± 10.6 mV). Similar to the 25 kDa-branched PEI (bPEI₂₅) and Lipofectamine RNAiMAX, human umbilical vein endothelial cells (HUVECs) significantly internalized PEI-DA/LNA-92a polyplexes without any obvious cytotoxicity. Down-regulation of miR-92a following the polyplex-mediated delivery of LNA-92a led to a substantial increase in the integrin subunit alpha 5 (ITGA5), the sirtuin-1 (SIRT1) and Krüppel-like factors (KLF) KLF2/4 expression, formation of capillary-like structures by HUVECs, and migration rate of HUVECs in vitro. Furthermore, PEI-DA/LNA-92a resulted in significantly enhanced capillary density in a chicken chorioallantoic membrane (CAM) model. Localized angiogenesis was substantially induced in the subcutaneous tissues of mice by sustained release of PEI-DA/LNA-92a polyplexes from an in situ forming, biodegradable hydrogel based on clickable poly(ethylene glycol) (PEG) macromers. Our results indicate that PEI-DA conjugates efficiently deliver LNA-92a to improve angiogenesis. Localized delivery of RNA interference (RNAi)-based therapeutics via hydrogel-laden PEI-DA polyplex nanoparticles appears to be a safe and effective approach for different therapeutic targets.

局部刺激血管生成是改善缺血或损伤组织修复的一种有吸引力的策略。据报道，几种 microRNAs (miRNAs)，如 miRNA-92a (miR-92a)，对缺血性疾病中的血管生成负调节作用。为了利用 miR-92a 抑制剂的临床潜力，需要建立安全有效的递送方法。在这里，我们使用脱氧胆酸修饰的聚乙烯亚胺聚合物偶联物 (PEI-DA) 在体外和体内递送基于锁定核酸 (LNA) 的 miR-92a 抑制剂 (LNA-92a)。带正电荷的 PEI-DA 偶联物将带负电荷的抑制剂凝聚成具有正净电荷 (34.2 ± 10.6 mV) 的纳米级复合物 (135 ± 7.2 nm)。类似于 25 kDa 支化 PEI (bPEI ₂₅) 和 Lipofectamine RNAiMAX，人脐静脉内皮细胞 (HUVEC) 显着内化 PEI-DA/LNA-92a 复合物，没有任何明显的细胞毒性。复合物介导的 LNA-92a 递送后 miR-92a 的下调导致整合素亚基 alpha 5 (ITGA5)、sirtuin-1 (SIRT1) 和 Krüppel 样因子 (KLF) KLF2/4 的显着增加HUVECs 的表达、毛细血管样结构的形成以及 HUVECs 在体外的迁移率。此外，PEI-DA/LNA-92a 导致鸡绒毛尿囊膜 (CAM) 模型中的毛细血管密度显着增强。通过从基于可点击聚（乙二醇）（PEG）大分子单体的原位形成、可生物降解的水凝胶中持续释放 PEI-DA/LNA-92a 复合物，在小鼠皮下组织中显着诱导了局部血管生成。我们的结果表明，PEI-DA 偶联物有效地传递 LNA-92a 以改善血管生成。通过载有水凝胶的 PEI-DA 复合纳米粒子局部递送基于 RNA 干扰 (RNAi) 的疗法似乎是针对不同治疗靶点的安全有效的方法。