Pathophysiological analysis and gene therapy of thoracic and abdominal aortic aneurysm

1. 腹主动脉瘤（AAA）和胸主动脉瘤形成的发病机制尚不清楚。削弱细胞外基质的酶在斑块破裂和平滑肌细胞（SMC）迁移中显得至关重要，并可能有助于动脉瘤的形成。基质金属蛋白酶（MMPs）降解血管细胞外基质成分，并受基质金属蛋白酶（TIMPs）的组织抑制剂调节。SMCs也可能通过局部产生各种蛋白酶及其抑制剂参与基质重塑。为了确定血管SMCs的表型调节和蛋白水解活性是否与动脉内侧退变有关，我们检测了17例接受手术治疗的AAA患者SMCs中的smo形、MMPs和TIMPs。我们澄清了在病变主动脉中，平衡转移到SMemb优势。SMemb在动脉瘤中的表达随着MMP的增强而增加，SMemb/SM2和MMP/TIMP的显著失衡显示在动脉瘤中。第二个项目的目标是探索MMPs基因治疗在稳定主动脉瘤方面有效的可能性。我们用hvj脂质体法检测了基因转移到血管壁的有效性和安全性。由于慢性排斥反应与aaa血管病变的发病机制相似，我们以异位移植的小鼠心脏及其冠状动脉为动物模型，采用hvj -脂质体法在移植前将fitc标记的ODN输注于移植心脏的冠状动脉冰敷10min。移植心脏冠状动脉FITC检测时间长达2周。在该动物模型中，反义bcl-x和PCNA ODN均能有效抑制新生内膜的形成。为了确保这项技术的安全性，我们还在猴子身上进行了异位心脏移植。将E2F诱饵DNA片段与小鼠模型一样转移到外植心脏中。诱饵在供体心脏上表达，受者表现健康。我们的结论是，这种技术是有用的ODN输送到动脉壁。下一步将包括反义MMP ODN或MMP核酶的生成和动物模型的建立，利用这些实验系统可以评估基因治疗对MMP的抑制效果。少

1. The pathogenesis of aortic abdominal aneurysm (AAA) and thoracic aneurysm formation remains uncertain. Enzymes that weaken the extracellular matrix appear crucial in plaque rupture and smooth muscle cell (SMC) migration and may contribute to aneurysm formation. Matrix metalloproteinases (MMPs) degrade components of the vascular extracellular matrix and are regulated by tissue inhibitors of matrix metalloproteinases (TIMPs). SMCs may also participate in matrix remodeling through localized production of various proteinases and their inhibitors. To determine whether phenotypic modulation and proteolytic activity in vascular SMCs contributes to arterial medial degeneration, we examined Smisoforms, MMPs and TIMPs in SMCs in 17 patients with AAA who underwent surgical treatment. We clarified that balance shifted to SMemb predominance in the diseased aortas. SMemb expression is increased in aneurysm with MMP enhancement, and a significant imbalance of SMemb/SM2 and MMP/TIMP was revealed in … More rapid progression of AAA.2. The goal of the second project was to explore the possibility that gene therapy of MMPs is effective in stabilizing aortic aneurysm. We tested an efficacy and safety of gene transfer to the vessel wall by HVJ-liposome method. We used ectopically transplaned murine heart and its coronary arteries as an animal model, because of the similarity in pathogenesis of vascular lesions between chronic rejection and AAA.FITC-labeled ODN was infused into coronary arteries of explanted heart before transplantation on ice for ten minutes by HVJ-liposome method. FITC was detected on coronary arteries of transplanted heart as long as 2 weeks. Antisense bcl-x and PCNA ODN were effective in inhibition of neointimal formation in this animal model. We also used ectopic heart transplatation in monkeys to ensure the safety of this technology. E2F decoy DNA fragment was transferred to explanted heart just as the mouse model. The decoy was expressed on donor heart and recipients appeared healthy. We conclude that this technique is useful for delivery of ODN to arterial wall.3. Next step would include generation of antisense MMPs ODN or MMP ribozyme and development of an animal model of AAA.The effect of MMP inhibition by gene therapy could by evaluated using these experimental systems. Less