Department of Cardiothoracic Surgery, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China.
Acta Biochim Biophys Sin (Shanghai). 2014 Feb;46(2):141-8. doi: 10.1093/abbs/gmt139. Epub 2013 Dec 29.
Restenosis is one of clinical limitations for vein graft in coronary bypass graft. It has been proved that signal pathway IGF-1 and its receptor (IGF-1R) activated by hemodynamic mechanical stretch are responsible for the vascular smooth muscle cells proliferation in vein graft neointima formation. Unfortunately, there is no routinely successful method to resolve this problem. Gene delivering to vein graft possesses great therapeutic potential to prevent neointima formation. Polymer is one kind of nanoparticles, which can activate the process of endocytosis of cells. In this study, we evaluated the transfection efficiency and therapeutic potential of polymer-based transfection of plasmids expressing GFP and shRNAs targeting IGF-1R (pGFPshIGF-1Rs) to smooth muscle cells and rabbit external jugular vein graft. Results showed that polymer-based transfection provided high efficiency of transgene expression in smooth muscle cells in vitro. In vitro, IGF-1R-specific shRNA transfected by polymer inhibited IGF-1R protein expression by 52 ± 3.6%, when compared with mock transfected cells. In vivo delivering efficiency of pGFPshIGF-1R plasmid into the rabbit external jugular vein graft was significantly high in the polymer-based transfection group, when compared with negative control group. In vivo, polymer-based transfection IGF-1R-specific shRNA efficiently inhibited the expression of IGF-1R protein by 77 ± 3.6%, 65.6 ± 4.9%, and 76.7 ± 4.3% at 24, 48, and 72 h, respectively, when compared with negative control group. Our findings indicated that polymer-based transfection may be a promising technique that allows the targeting of gene therapy for vein graft restenosis.
再狭窄是冠状动脉旁路移植术中静脉移植物的临床局限性之一。已经证明，由血流机械拉伸激活的信号通路 IGF-1 及其受体（IGF-1R）负责静脉移植物新内膜形成中的血管平滑肌细胞增殖。不幸的是，目前尚无常规有效的方法来解决这个问题。将基因导入静脉移植物具有预防新内膜形成的巨大治疗潜力。聚合物是一种纳米颗粒，可以激活细胞内吞作用的过程。在这项研究中，我们评估了聚合物基转染表达 GFP 和靶向 IGF-1R 的 shRNA（pGFPshIGF-1Rs）的质粒对平滑肌细胞和兔颈外静脉移植物的转染效率和治疗潜力。结果表明，聚合物基转染在体外平滑肌细胞中提供了高效的转基因表达。在体外，聚合物转染的 IGF-1R 特异性 shRNA 抑制 IGF-1R 蛋白表达 52±3.6%，与 mock 转染细胞相比。在体内，与阴性对照组相比，聚合物基转染 pGFPshIGF-1R 质粒进入兔颈外静脉移植物的效率显著提高。在体内，聚合物基转染 IGF-1R 特异性 shRNA 可有效抑制 IGF-1R 蛋白的表达，在 24、48 和 72 h 时分别为 77±3.6%、65.6±4.9%和 76.7±4.3%，与阴性对照组相比。我们的研究结果表明，聚合物基转染可能是一种有前途的技术，允许针对静脉移植物再狭窄的基因治疗。
