Gene therapy to prevent vascular remodeling-vascular smooth muscle cell as a target cell

血管平滑肌细胞（VSMC）在血管内膜内的迁移、增殖和基质合成在血管成形术后再狭窄中起重要作用。冠状动脉再狭窄仍然是一个主要的未解决的限制介入心脏病学。它是冠状动脉血管化过程中发生的动脉损伤的结果，很大程度上是由新生内膜增生引起的，特别是在支架内。为了开发新的治疗策略，我们进行了以下研究。Akt（PKB）是一种丝氨酸-苏氨酸蛋白激酶，其通过磷脂酰肌醇3-激酶（P1 3-kinase）途径被各种细胞外刺激激活。Akt在细胞凋亡、细胞增殖、糖代谢和血管生成中起重要作用。平滑肌细胞具有三种肌苷重链亚型：SM 1、SM 2和SM emb。血管成形术后，VSMCs的表型由分化表型（SM 1和SM 2）转变为去分化表型（SM emb）。Akt调节这些VSMC表型变化。亚丁 ...更多信息 组成型活性Akt 1（Adeno-myrAkt）的病毒转导增加SM 1和SM 2的表达。相反，显性阴性Akt 1增加SMemb表达。接下来，我们尝试将目的基因转染到VSMCs中。将涂有含有质粒DNA的聚氨酯乳液的金属支架植入兔股动脉中，以评价血管壁中的转基因递送和表达。在植入后7天评价质粒编码的标记基因β-半乳糖苷酶、荧光素酶和绿色荧光蛋白（GEP）的表达。转基因表达的程度取决于装载到支架上的DNA的量，在接受裸金属支架或缺乏质粒DNA的聚合物涂层支架的血管段中未检测到信号。最后，共定位研究确定了血管平滑肌细胞和巨噬细胞中的转基因表达。这些数据证明了涂层支架用于将基因局部、剂量依赖性递送至血管壁中的多种细胞类型的效用。少

Vascular smooth muscle cell (VSMC) migration, proliferation, and matrix synthesis within the intima of vessels play an important role in post-angioplasty restenosis. Coronary artery restenosis remains a major unresolved limitation for interventional cardiology. It results from arterial injury incurred during coronary vascularization and is caused in large part bu neointimal hyperplasia, especially within stents. To develop a new therapeutic strategy, we performed following studies. Akt (PKB) is a serine-threonine protein kinase that is activated by various extracellular stimuli through the phosphatidylinositol 3-kinase (P1 3-kinase) pathway. Akt plays an important role in apoptosis, cell proliferation, glucose metabolism and angiogenesis. VSMCs have three isoforms of myosine heavy chains : SM 1,SM 2 and SM emb. After angioplasty, VSMCs change their phenotype from differentiated phenotype (SM 1 and SM 2) to dedifferentiated one (SM emb). Akt regulates these VSMC phenotypic changes. Aden … More oviral transduction of constitutive-active Akt 1 (Adeno-myrAkt) increased expression of SM 1 and SM2. Conversely, dominant-negative Akt 1 increased SMemb expression. Next, we try to transfect target gene to VSMCs in vivo. Metallic stents coated with a polyurethane emulsion containing plasmid DNA were implanted in rabbit femoral arteries to evaluate transgene delivery and expression in the vessel wall. The expression of the plasmid-encoded marker genes, β-galactosidase, luciferase and green fluorescence protein (GEP), were evaluated at 7 days after implantation. The extent of transgene expression was dependent upon the quantity of DNA loaded onto the stent, no signal was detected in vessel segments that received bare metallic stents or polymer-coated stents lacking plasmid DNA. Finally, co-localization studies identified transgene expression in both vascular smooth muscle cells and macrophages. These data demonstrate the utility of coated stents for the local, dose-dependent delivety of genes to multiple cell types in the vessel wall. Less