Acute Phase Protein Effects in Cellular Mechanisms of Microvascular Endothelium

描述(申请人提供)：在过去的十年里，免疫系统的失调已经变得明显与几种严重的疾病有关，包括糖尿病、心血管疾病和慢性炎症。数以百万计的美国人受到这些疾病的影响，导致医疗费用增加。在这些疾病中，免疫/炎症反应的失衡最终导致细胞损伤和病理生理功能障碍，如神经病变和缺血。虽然临床医生正在努力确定用于确定或监测这些疾病的严重性的关键生物标记物，但几乎没有做过识别炎性生物标记物对微血管系统共同靶点的直接影响的工作。急性时相蛋白(APP)的释放，包括结合珠蛋白、血清淀粉样蛋白A和C反应蛋白，在许多此类疾病中都会发生，但这些炎性生物标志物对细胞的潜在影响尚不清楚。我们的假设是，炎症介质，如APP，直接作用于微血管系统的内皮细胞，激活信号通路和细胞机制，改变正常的内皮屏障功能。这项建议的重点是检查暴露于APP后微血管的变化，以更好地了解导致鼠疫发展和内皮运输中断的潜在机制。利用体外血脑屏障模型(原代分离的大鼠脑微血管内皮细胞，RBMEC)和外周微血管内皮细胞模型(人脐静脉内皮细胞系，HUVEC)，我们将研究APP反应微血管内皮细胞屏障结构和分子变化的细胞机制。将进行功能(血脑屏障通透性)、结构(紧密连接蛋白的表达)和分子(相关炎症细胞因子的释放)评估，以确定C-反应蛋白、结合珠蛋白等水平升高的临床表现与上述疾病患者微血管中观察到的病理生理变化之间的联系。这项研究的结果将为进一步研究由这些炎性生物标志物激活的细胞信号通路提供概念证明，并确定将降低这些疾病患者的风险和改善生活质量的理想药物治疗。这项研究建议的重点是加强我们对微血管内皮细胞对炎性介质，特别是急性时相蛋白的反应的细胞机制的了解。这项研究的结果将提供关于急性时相蛋白(即C-反应蛋白、结合珠蛋白和血清淀粉样蛋白A)刺激微血管内皮细胞屏障的作用的宝贵信息，包括调节这些屏障的通透性和相关结构蛋白。公共卫生相关性：这些研究的临床影响将为那些患有心血管和炎症相关疾病的患者提供治疗和预防措施的目标。

DESCRIPTION (provided by applicant): Over the last decade, it has become apparent that dysregulation of the immune system is related to several serious diseases, including include diabetes, cardiovascular diseases, and chronic inflammation. Millions of Americans are affected by these diseases and results in increased healthcare costs. The imbalance of the immune/inflammatory responses in these diseases ultimately leads to cellular damage and pathophysiologic dysfunction like neuropathy and ischemia. While clinicians are working to identify key biomarkers to use in determining or monitoring the seriousness of these diseases, little has been done to identify the direct effects that inflammatory biomarkers have on the common target of the microvasculature. The release of acute phase proteins (APP), including haptoglobin, serum amyloid A, and C-reactive protein, occurs in many of these diseases, yet the underlying cellular impact of these inflammatory biomarkers is not well understood. Our hypothesis is that inflammatory mediators, such as APPs, act directly on the endothelial cells of the microvasculature, activating signaling pathways and cellular mechanisms that alter the normal endothelial barrier function. This proposal focuses on examining changes in the microvasculature following exposure to APPs to gain a better understanding of the underlying mechanisms that lead to plague development and disrupted endothelial transport. Using an in vitro BBB model (primary isolated rat brain microvessel endothelial cells, RBMEC) and a peripheral microvascular endothelial model (human umbilical vein endothelial cell line, HUVEC) we will examine the cellular mechanisms that are likely involved in structural and molecular changes of the microvascular endothelial barrier in response to APPs. Functional (BBB permeability), structural (expression of tight junction proteins) and molecular (release of related inflammatory cytokines) assessments will be carried out to establish a link between clinical findings of elevated levels of C-reactive protein, haptoglobin, etc. and the pathophysiological changes observed in the microvasculature of patients from afore mentioned diseases. The results from this study will provide the proof of concept for further investigation into clarifying cellular signaling pathways that are activated by these inflammatory biomarkers as well as identify ideal pharmacological treatments that will reduce the risks and improve the quality of life in patients with these diseases. The focus of this research proposal is to enhance our understanding of cellular mechanisms in the microvascular endothelium which respond to inflammatory mediators, especially acute phase proteins. The results of this study will provide invaluable information regarding the effects that acute phase proteins (i.e., C-reactive protein, haptoglobin, and serum amyloid A) stimulate in the microvascular endothelial barrier including permeability and related structural proteins that regulate these barriers. PUBLIC HEALTH RELEVANCE: The clinical impact of these studies will provide targets for therapeutic treatment as well as preventive measures for those patients with cardiovascular and inflammatory-related diseases.