Neurohumoral regulation of PVAT

项目摘要--项目II 心血管疾病是全球主要的死亡原因，包括多种疾病，包括 动脉粥样硬化、高血压、中风和心力衰竭。血液和血液之间存在着直接的正相关关系 血压和心血管疾病的风险，但导致异常血压的因素 人们对疾病的调控还不完全了解。血管周围脂肪组织(PVAT)是最近出现的 作为血管紧张度和血压的关键调节器。PVAT包围了大部分血管和 释放抗收缩因子。抗收缩介质的产生是由交感神经驱动的 神经递质去甲肾上腺素(NE)，但驱动这种作用的NE来源尚不清楚。这个 这项建议的总体目标是了解PVAT中介导神经传递的机制。 健康和疾病。促进脂肪细胞活性的潜在机制包括通过以下方式局部产生介质 非神经细胞、神经支配或循环神经递质。这项提议考验着中央银行 假设脂肪细胞摄取和释放去甲肾上腺素介导的自分泌信号是主要的 PVAT脂肪细胞活性的调节，而神经神经和循环因子起次要作用。此外， 我们认为PVAT脂肪细胞的突触前功能在产生血管的条件下发生了变化 疾病。这一假设将在两个特定的目标上进行检验，这两个目标将研究男性的肠系膜和主动脉PVAT 和雌性动物在健康和疾病期间。实验将利用有针对性的基因追踪和组织 清除以确定神经和脂肪细胞之间的物理相互作用，基因编码的钙 研究脂肪细胞激活的指标，测试脂肪细胞激活的功能相关性的化学发生学， 荧光假神经递质研究脂肪细胞和RNA摄取和释放去甲肾上腺素的动力学 测序以了解疾病过程中特定的机制和途径是如何调节的。特定目标 1将验证NE对PVAT脂肪细胞的刺激涉及自分泌信号介导的假设 通过脂肪细胞，而不是直接神经支配或循环神经递质。这一目标的实验包括 基因报告系的解剖学研究，遗传编码指示物的钙成像， 血管张力功能分析中的化学遗传学和荧光假神经递质的测定 摄取和释放。特定目标2将检验PVAT脂肪细胞的突触前功能是 在产生血管疾病的情况下受损的。本研究的目的将采用高脂饮食的血管模型 并将通过RNA测序来研究候选机制。对脂肪细胞神经递质的影响 摄取、释放和反应性将使用荧光假神经递质和遗传学进行研究 编码的钙指示器。这项研究的结果将确定调节这些功能的新机制 是PVAT的。对驱动抗收缩因子释放的机制的新见解将有助于 开发治疗高血压等常见疾病的血管功能障碍的方法。

Project Summary – Project II Cardiovascular disease is the leading cause of death worldwide and encompasses multiple disorders including atherosclerosis, hypertension, stroke, and heart failure. There is a direct positive relationship between blood pressure and cardiovascular disease risk in humans, but the factors that contribute to abnormal blood pressure regulation in disease are incompletely understood. Perivascular adipose tissue (PVAT) has recently emerged as a key regulator of vascular tone and blood pressure. PVAT surrounds the majority of blood vessels and releases anticontractile factors. The production of anticontractile mediators is driven by the sympathetic neurotransmitter norepinephrine (NE), but the source of NE that drives this effect remains unknown. The overall goal of this proposal is to understand the mechanisms that mediate neurotransmission in PVAT in health and disease. Potential mechanisms that drive adipocyte activity include local production of mediators by non-neuronal cells, neural innervation, or circulating neurotransmitters. This proposal tests the central hypothesis that autocrine signaling mediated by the uptake and release of NE by adipocytes is the primary regulator of PVAT adipocyte activity, while neural innervation and circulating factors play minor roles. Further, we propose that the presynaptic functions of PVAT adipocytes are altered in conditions that produce vascular disease. This hypothesis will be tested in two specific aims that will study mesenteric and aortic PVAT in male and female animals during health and disease. Experiments will utilize targeted genetic tracing and tissue clearing to identify physical interactions between nerves and adipocytes, genetically encoded calcium indicators to study adipocyte activation, chemogenetics to test the functional relevance of adipocyte activation, fluorescent false neurotransmitters to study the dynamics of NE uptake and release in adipocytes, and RNA sequencing to understand how specific mechanisms and pathways are regulated during disease. Specific Aim 1 will test the hypothesis that the stimulation of PVAT adipocytes by NE involves autocrine signaling mediated by adipocytes rather direct neural innervation or circulating neurotransmitters. Experiments in this aim include anatomical studies in genetic reporter lines, calcium imaging with genetically encoded indicators, chemogenetics in functional assays of vascular tone, and measures of fluorescent false neurotransmitter uptake and release. Specific Aim 2 will test the hypothesis that presynaptic functions of PVAT adipocytes are impaired in conditions that produce vascular disease. This aim will use the high fat diet model of vascular dysfunction and will study candidate mechanisms with RNA sequencing. Effects on adipocyte neurotransmitter uptake, release, and responsiveness will be studied using fluorescent false neurotransmitters and genetically encoded calcium indicators. The results of this study will identify novel mechanisms that regulate the functions of PVAT. New insight into mechanisms that drive the release of anticontractile factors will facilitate the development of therapies for vascular dysfunction in common disorders, such as hypertension.