Acute Phase Protein Effects in Cellular Mechanisms of Microvascular Endothelium

描述（由申请人提供）：在过去的十年中，越来越明显的是，免疫系统的失调与多种严重疾病有关，包括糖尿病、心血管疾病和慢性炎症。数百万美国人受到这些疾病的影响，导致医疗费用增加。这些疾病中免疫/炎症反应的不平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志物，但几乎没有采取任何措施来确定炎症生物标志物对微血管系统共同目标的直接影响。许多此类疾病都会释放急性期蛋白 (APP)，包括触珠蛋白、血清淀粉样蛋白 A 和 C 反应蛋白，但这些炎症生物标志物的潜在细胞影响尚不清楚。我们的假设是，炎症介质（例如 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，从而改变正常的内皮屏障功能。该提案的重点是检查接触 APP 后微血管系统的变化，以更好地了解导致鼠疫发展和内皮运输中断的潜在机制。使用体外 BBB 模型（原代分离的大鼠脑微血管内皮细胞，RBMEC）和外周微血管内皮模型（人脐静脉内皮细胞系，HUVEC），我们将研究可能参与微血管内皮屏障响应 APP 的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，以建立C反应蛋白、触珠蛋白等水平升高的临床发现与在上述疾病患者的微血管系统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澄清这些炎症生物标志物激活的细胞信号传导途径提供概念证明，并确定理想的药物治疗方法，以降低这些疾病患者的风险并改善其生活质量。这项研究计划的重点是增强我们对微血管内皮细胞机制的理解，这些细胞机制对炎症介质，特别是急性期蛋白做出反应。这项研究的结果将提供关于急性期蛋白（即 C 反应蛋白、触珠蛋白和血清淀粉样蛋白 A）刺激微血管内皮屏障（包括通透性和调节这些屏障的相关结构蛋白）的影响的宝贵信息。公共卫生相关性：这些研究的临床影响将为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.