Cell and matrix interactions in diabetic vascular tissue engineering models

糖尿病是血管疾病的主要危险因素，几乎影响所有类型的血管， 口径在糖尿病中，血糖和血脂水平升高与长寿的 蛋白质，如来自血管壁的胶原蛋白和弹性蛋白，通过氧化和交联 过程，导致形成晚期糖基化终产物（AGEs）;结果是 血管硬化糖尿病的标志此外，血管细胞对糖尿病有反应- 相关的改变环境的激活和导致病理性重塑和发病， 血管疾病的进展。这些严重的细胞和细胞外基质（ECM）变化 导致炎症激活、愈合受损、纤维化和异位钙化。 AGEs与其受体β 1相互作用，刺激活性氧的产生 种，导致血管壁的功能障碍性重塑（硬化、纤维化和钙化）。 本项目的目的是描述糖尿病对血管外膜成纤维细胞及其增殖的影响。 参与血管病理学。通过使用基于组织工程原理的3D模型，我们 可以控制接种在基于血管基质的支架上的细胞类型，同时提供必要的 在生理生物反应器中的生物化学和机械刺激。该组织工程构建体可以 并将其植入糖尿病动物模型，探讨其对ECM氧化和AGE的影响 积累对外膜成纤维细胞的命运的影响。抗氧化抗炎作用 代理商也可以被监控。 我们的假设是，成纤维细胞被活性氧激活，并导致功能障碍， 血管壁对糖尿病引起的损伤的重塑。这一假设将是 在以下两个目标中进行测试。 在具体的目标1中，我们将研究糖尿病外膜成纤维细胞对糖尿病血管形成的作用。 病理性血管壁重塑血管ECM为基础的支架（脱细胞动脉）将是 接种人内皮细胞、平滑肌细胞和成纤维细胞，和a）在 B）在糖尿病介质中植入生理血管生物反应器2个月， 正常和糖尿病裸大鼠腹主动脉3个月和6个月。将监测移植物 氧化应激和炎症。 在具体目标2中，我们将探讨糖尿病外膜成纤维细胞在存在以下情况下的命运： 抗氧化剂和抗炎剂。基于ECM的血管支架接种有人 血管细胞将a）在生理血管生物反应器中在糖尿病培养基中孵育2个月 和B）作为转位移植物植入正常和糖尿病裸大鼠的腹主动脉中3 和6个月，在抗氧化剂多酚化合物，二甲双胍，胰岛素- 致敏剂药物和免疫调节间充质细胞（在单独的组中）。移植物将 监测氧化应激和炎症。 期望：在本研究结束时，我们将获得有关主要 由外膜成纤维细胞引发的血管壁中的糖尿病相关改变， 提供了针对这些事件的途径。

Diabetes is a major risk factor for vascular diseases that affects nearly all blood vessel types and calibers. In diabetes, elevated levels of blood glucose and lipids interact irreversibly with long-lived proteins, such as collagen and elastin from the blood vessel wall, via oxidation and crosslinking processes, resulting in formation of advanced glycation end products (AGEs); the consequence is vascular stiffening, the hallmark of diabetes. Furthermore, vascular cells respond to diabetes- related altered environment by activation and leading to pathological remodeling and to the onset and progression of vascular disease. Together, these severe cell and extracellular matrix (ECM) changes result in activation of inflammation, impaired healing, fibrosis, and ectopic calcification. The interaction of AGEs with their receptor, RAGE, stimulates the production of reactive oxygen species, leading to dysfunctional remodeling of the vascular wall (stiffening, fibrosis, and calcification). The goal of this project is to characterize the effect of diabetes on the adventitial fibroblasts and their involvement in vascular pathology. By using 3D models based on tissue engineering principles, we can control the type of cells seeded on a vascular matrix-based scaffold while providing the necessary biochemical and mechanical stimuli in a physiologic bioreactor. The tissue engineered construct can also be implanted in diabetic animal models, to explore the effect of ECM oxidation and AGE accumulation on the fate of adventitial fibroblasts. The effect of antioxidant and anti-inflammatory agents can also be monitored. Our hypothesis is that fibroblasts are activated by ROS and contribute to the dysfunctional remodeling of the vascular wall in response to diabetes-induced injuries. This hypothesis will be tested in the following two aims. In specific Aim 1 we will investigate the contribution of diabetic adventitial fibroblasts to the pathological vascular wall remodeling. Vascular ECM-based scaffolds (acellular arteries) will be seeded with human endothelial cells, smooth muscle cells, and fibroblasts and a) incubated in a physiologic vascular bioreactor for 2 months in diabetic media, b) implanted as transposition grafts in the abdominal aorta of normal and diabetic nude rats for 3 and 6 months. Grafts will be monitored for oxidative stress and inflammation. In specific Aim 2 we will explore the fate of diabetic adventitial fibroblasts in the presence of antioxidant and anti-inflammatory agents. Vascular ECM-based scaffolds seeded with human vascular cells will be a) incubated in a physiologic vascular bioreactor for 2 months in diabetic media and b) implanted as transposition grafts in the abdominal aorta of normal and diabetic nude rats for 3 and 6 months, in the presence of antioxidant polyphenolic compounds, metformin, an insulin- sensitizer drug, and immunomodulatory mesenchymal cells (in separate groups). Grafts will be monitored for oxidative stress and inflammation. Expectations: at the conclusion of this study, we would gain important information about the major diabetes-related alterations in the vascular wall initiated by the adventitial fibroblasts, potentially offering avenues for targeting these events.