Rab27a functions in the vascular microenvironment

Rab27a 在血管微环境中发挥作用

• 批准号: 10597700
• 负责人: Caitlin Patricia Stieber
• 金额: $ 3.37万
• 依托单位: MAINEHEALTH
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-15 至 2024-04-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10597700
• 关键词: 3-Dimensional; Adipocytes; Adipose tissue; Affect; Aorta; Atherosclerosis; Blood Vessels; Blood capillaries; Cardiac Surgery procedures; Cardiovascular Diseases; Cardiovascular Physiology; Cause of Death; Cell Differentiation process; Cell model; Cell physiology; Cells; Characteristics; Clinical; Coculture Techniques; Collagen Fiber; Collection; Coronary Arteriosclerosis; Coronary Artery Bypass; Data; Development; Diagnosis; Disease; Disease Progression; Endothelial Cells; Environment; Epidemic; Experimental Designs; Fatty acid glycerol esters; Fellowship; Future; Hand; Heart Abnormalities; Human; In Vitro; Individual; Laboratories; Link; Lipids; Macrophage; Mediating; Metabolic; Methods; Mitral Valve; Modeling; Molecular; Molecular Analysis; Mus; Nerve; Obesity; Operative Surgical Procedures; Paracrine Communication; Pathogenicity; Pathology; Patients; Persons; Phenotype; Physiology; Population; Predisposition; Prevalence; Production; Proliferating; Proteins; Publications; Research; Research Personnel; Research Project Grants; Role; Sampling; Scientist; Signal Transduction; Small Interfering RNA; Smooth Muscle Myocytes; T-Lymphocyte; Testing; Tissue Donors; Tissue Expansion; Tissue Sample; Training; Translational Research; Vascular Diseases; Vascular Smooth Muscle; Vasodilation; Work; adipocyte differentiation; adipokines; atherogenesis; cardiac repair; congenital heart disorder; cytokine; diet-induced obesity; experience; experimental study; human tissue; improved; in vivo; interest; knock-down; lipid biosynthesis; mortality; mouse model; novel; obese person; paracrine; progenitor; repaired; skills; stem cells; trafficking; translational study; vasoconstriction

Cardiovascular disease is the leading cause of death in the USA. Rates of cardiovascular disease have increased along with the prevalence of obesity. Perivascular adipose tissue (PVAT) surrounds most vessels in the body and regulates the underlying blood vessel, providing a local cellular link between obesity and cardiovascular function. In metabolically healthy individuals, PVAT induces an antiproliferative and vasorelaxation phenotype of smooth muscle cells. Conversely, in obese individuals, PVAT induces vasoconstriction. Because paracrine signaling from PVAT regulates vascular physiology, we predict that the adipocytes within PVAT are an important determinant of susceptibility to vascular disease. Our laboratory has previously shown that the trafficking molecule RAB27a is increased in mouse PVAT in a model of diet induced obesity, and also is expressed in human PVAT derived from patients with cardiovascular disease. Further, suppression of RAB27a function in human PVAT-derived preadipocytes inhibits their differentiation. This project will study the mechanism by which RAB27a controls adipogenesis in human PVAT-derived progenitors. Further, this project will determine how changes in RAB27a expression in human adipocytes changes their signaling to vascular smooth muscle cells. We hypothesize that RAB27a controls the secretion of pro- adipogenic adipokines and that these adipokines regulate both preadipocytes and potentially also vascular smooth muscle cells. To test these ideas, we have established an ongoing collection and banking of human PVAT from donors with different levels of cardiovascular disease. One group consists of patients undergoing coronary artery bypass grafting (CABG) due to severe coronary artery disease, and a second group includes patients undergoing mitral valve repair, without vascular disease. For each sample, we derive primary preadipocyte cultures from the stromal vascular fraction. Several primary preadipocyte populations from each donor type have been established. We also developed a unique three-dimensional human adiposphere model to more closely mimic the organization of PVAT in vivo. With these unique human cell models in hand, our proposal will address two aims. Aim 1 will identify the mechanism by which RAB27a regulates adipogenesis in human PVAT-derived adipocyte progenitor cells. Aim 2 will identify how RAB27a in PVAT-derived adipocytes affects paracrine secretion and smooth muscle cells. These studies will provide novel information about RAB27a function in the vascular microenvironment and how it modifies the secretion of adipokines and potential vasoactive factors. In the future, I want to be a bench researcher, and this research project is an excellent training vehicle to help me develop and improve my skills such as experimental design using human tissues, experience in translational research, and analysis of molecular and cellular characteristics compared to clinical features of donors. Through this fellowship, I will have the opportunity to develop the necessary skills to be an independent research scientist.

心血管疾病是美国的首要死因。心血管疾病的发病率 随着肥胖症的流行而增加。血管周围脂肪组织（PVAT）包围着大多数血管 身体并调节底层血管，在肥胖和肥胖之间提供局部细胞联系 心血管功能。在代谢健康的个体中，PVAT 会诱导抗增殖和 平滑肌细胞的血管舒张表型。相反，在肥胖个体中，PVAT 会诱导 血管收缩。由于 PVAT 的旁分泌信号调节血管生理学，我们预测 PVAT 内的脂肪细胞是血管疾病易感性的重要决定因素。我们实验室有 先前表明，在饮食诱导的模型中，小鼠 PVAT 中的运输分子 RAB27a 增加 肥胖症，并且也在源自心血管疾病患者的人类PVAT中表达。更远， 抑制人 PVAT 衍生的前脂肪细胞中的 RAB27a 功能会抑制其分化。这 该项目将研究 RAB27a 控制人类 PVAT 衍生祖细胞脂肪生成的机制。 此外，该项目将确定人类脂肪细胞中 RAB27a 表达的变化如何改变其 向血管平滑肌细胞发出信号。我们假设 RAB27a 控制前体的分泌 脂肪形成脂肪因子，这些脂肪因子既调节前脂肪细胞，也可能调节血管 平滑肌细胞。为了测试这些想法，我们建立了一个持续的人类收集和银行库 来自患有不同程度心血管疾病的捐赠者的 PVAT。一组由接受治疗的患者组成 由于严重冠状动脉疾病而进行的冠状动脉旁路移植术（CABG），第二组包括 接受二尖瓣修复术且无血管疾病的患者。对于每个样本，我们得出主要 来自基质血管部分的前脂肪细胞培养物。来自每个细胞的几个原代前脂肪细胞群 捐助者类型已确定。我们还开发了独特的三维人体脂肪层模型 更接近地模拟PVAT体内的组织。有了这些独特的人体细胞模型，我们 该提案将解决两个目标。目标 1 将确定 RAB27a 调节脂肪生成的机制 人PVAT衍生的脂肪细胞祖细胞。目标 2 将确定 RAB27a 在 PVAT 衍生脂肪细胞中的作用 影响旁分泌分泌和平滑肌细胞。这些研究将提供有关以下方面的新信息： RAB27a 在血管微环境中的功能及其如何改变脂肪因子和 潜在的血管活性因素。将来我想成为一名替补研究员，这个研究项目是一个 优秀的培训工具可以帮助我发展和提高我的技能，例如使用人类进行实验设计 组织、转化研究经验以及分子和细胞特征比较分析 捐献者的临床特征。通过这次奖学金，我将有机会发展必要的技能 成为一名独立研究科学家。