Shen Yuqin, Liu Yin, Gao Han, Fei Hongbo, Yu Wenwen, Hu Tianqi, Zheng Yi, Bi Xueting, Lin Chongtao
Department of Periodontics, School and Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 China
Department of Orthodontics, School and Hospital of Stomatology, Jilin University 1500 Qinghua Road Changchun 130021 China.
RSC Adv. 2018 Feb 20;8(15):8080-8088. doi: 10.1039/c7ra12548h. eCollection 2018 Feb 19.
Oral bone defects are difficult to treat. Recently, endogenous miR-34a was shown to be involved in bone anabolism. Clinical application of such microRNAs requires the inherent instability of microRNAs to be overcome by an efficient delivery system. In this study, we employed -acetyl-l-leucine-modified polyethylenimine (-Ac-l-Leu-PEI) as an miR-34a carrier and evaluated its delivery ability, transfection efficiency, cytotoxicity and whether it enhanced osteogenic differentiation and bone formation and . Stable -Ac-l-Leu-PEI/miR-34a nanocomplexes were synthesized at a mass ratio of 4 and had a small size (190.34 nm), a low zeta potential (21.1 mV), a high transfection efficiency (69.39%) and no cytotoxicity in MG63 cells. -Ac-l-Leu-PEI-mediated miR-34a delivery promoted ALP activity and expression of osteogenic differentiation markers, , and to higher levels than those produced by Lipofectamine 2000-mediated delivery. -Ac-l-Leu-PEI also achieved delivery of miR-34a to a local cranial bone defect area with miR-34a retaining the ability to initiate significant new bone formation 12 weeks post-implantation. This demonstrates the potential for -Ac-l-Leu-PEI as a gene therapy vehicle for the regeneration of bone defects.
口腔骨缺损难以治疗。最近，内源性miR-34a被证明参与骨合成代谢。此类微小RNA的临床应用需要通过高效的递送系统来克服微小RNA固有的不稳定性。在本研究中，我们采用α-乙酰基-L-亮氨酸修饰的聚乙烯亚胺（α-Ac-L-Leu-PEI）作为miR-34a载体，并评估其递送能力、转染效率、细胞毒性以及是否能增强成骨分化和骨形成。以质量比4合成了稳定的α-Ac-L-Leu-PEI/miR-34a纳米复合物，其粒径小（190.34 nm）、zeta电位低（21.1 mV）、转染效率高（高达69.39%），且对MG63细胞无细胞毒性。α-Ac-L-Leu-PEI介导的miR-34a递送使碱性磷酸酶（ALP）活性和成骨分化标志物（如Runx2、Osterix和骨钙素）的表达水平高于脂质体2000介导的递送。α-Ac-L-Leu-PEI还实现了将miR-34a递送至局部颅骨缺损区域，且在植入后12周miR-34a仍保持引发显著新骨形成的能力。这证明了α-Ac-L-Leu-PEI作为骨缺损再生基因治疗载体的潜力。
