EFFECT OF LIPIDS ON VASCULAR GRAFT HEALING

描述（改编自申请人摘要）：使用假体移植物 广泛用于血管重建手术，但其长期通畅性 有限，可能是由于氧化低密度引起的细胞功能改变 脂蛋白（oxLDL）。在初步研究中，他们已经表明：1）移植 材料刺激单核细胞在体外氧化LDL，2）这种oxLDL 在体内抑制内皮细胞（EC）迁移。这有助于 这些移植物的长期血栓形成和最终失效。的目标 本项目旨在确定脂质，尤其是氧化脂质， 关于假体移植物上的EC迁移。 为了验证他们的假设，氧化脂质对EC迁移的影响以及 将研究oxLDL抑制EC迁移的机制。的 研究人员将首先研究活性氧（ROS）的作用 oxLDL抑制EC迁移。他们将描述的影响， oxLDL对EC产生超氧化物的影响，评估ROS对EC的影响 迁移，并确定抗氧化剂恢复EC迁移的能力 在oxLDL的存在下。由于ROS改变了膜的流动性， 流动性影响迁移，他们将研究oxLDL对EC的影响 膜流动性他们还将评估维生素E和其他 抗氧化剂，以防止膜流动性的变化和保护EC迁移。 将在体外研究oxLDL对ePTFE移植物材料上EC迁移的影响。 研究表明，维生素E或超氧化物歧化酶的能力， 迁移决定。最后，他们将研究 高胆固醇血症对EC长入植入的人工移植物的影响 兔，并评估维生素E保护内皮迁移的能力。 拟议的研究将调查脂质和脂蛋白的作用， 它们的氧化修饰衍生物，在合成血管的失败中， 移植物内皮化。研究还将探讨治疗的有效性 饮食中的抗氧化剂来控制脂质氧化和促进移植愈合。 这将有助于更好地了解脂质在 移植失败的病理生理学。最终，这可能会导致一些方法， 促进人工血管内皮化，延长 小直径血管移植物。

DESCRIPTION (Adapted from Applicant's Abstract): Prosthetic grafts are used widely in vascular reconstructive surgery, but their long-term patency is limited, perhaps due to altered cell function caused by oxidized low density lipoprotein (oxLDL). In preliminary studies they have shown that: 1) graft material stimulates monocytic cells to oxidize LDL in vitro, 2) this oxLDL inhibits endothelial cell (EC) migration in vivo. This contributes to the prolonged thrombogenicity and eventual failure of these grafts. The goal of this project is to determine the effect of lipids, especially oxidized lipids, on EC migration on prosthetic grafts. To test their hypothesis, the effect of oxidized lipids on EC migration and the mechanism by which oxLDL inhibits EC migration will be studied. The investigators will first investigate the role of reactive oxygen species (ROS) in oxLDL's inhibition of EC migration. They will characterize the effect of oxLDL on superoxide production by EC, assessing the effect of ROS on EC migration, and determining the ability of antioxidants to restore EC migration in the presence of oxLDL. Since ROS alter membrane fluidity and changes in fluidity affect migration, they will investigate the effect of oxLDL on EC membrane fluidity. They will also evaluate the ability of vitamin E and other antioxidants to prevent changes in membrane fluidity and preserve EC migration. The effect of oxLDL on EC migration on ePTFE graft material in vitro will be studied, and the ability of vitamin E or superoxide dismutase to restore migration determined. Finally, they will study the effect of hypercholesterolemia on EC ingrowth onto prosthetic grafts implanted in rabbits, and assess the ability of vitamin E to preserve endothelial migration. The proposed studies will investigate the role of lipids and lipoproteins, and their oxidatively modified derivatives, in the failure of synthetic vascular grafts to endothelialize. Studies will also address the efficacy of treatment with dietary antioxidants to control lipid oxidation and promote graft healing. This will lead to a better understanding of the role of lipids in the pathophysiology of graft failure. Ultimately, this may lead to methods to promote endothelialization of prosthetic grafts and prolong patency of small-diameter vascular grafts.