Investigating the impact of a fatty acid-cRel inflammatory circuit in atherosclerosis

R01：研究脂肪酸-cRel炎症循环在动脉粥样硬化中的影响 摘要/摘要 这项资助的目的是了解炎症和脂肪代谢是如何通过体内循环联系在一起的。 巨噬细胞，以及这些回路是否影响心脏新陈代谢疾病。尽管脂类的扰动 在许多人类疾病中，动态平衡被认为与炎症有关，我们的 对这些进程“如何”和“为什么”密切相关的理解仍然有限。最近的研究揭示了 促炎信号可以重新编程巨噬细胞的脂质代谢状态。它也变得清晰起来 巨噬细胞的炎症机制可以感觉到脂质稳态的扰动，从而 诱导和调节炎症反应。因此，脂质稳态和炎症是相互联系的， 其中一个的扰动会影响另一个。在这项建议中，我们结合了先进的分析质谱学- 基于炎症遗传模型的方法，目标是定义炎症的机制 炎症促使脂体重新编程(反之亦然)。具体目标1是确定 单不饱和脂肪酸(MUFA)稳态改变调节炎症反应的机制 激活的巨噬细胞。具体地说，我们将继续我们的发现，阻止从头合成多不饱和脂肪酸 通过核因子-κB成员CREL增强炎症反应。利用转录组学的组合，ATAC- SEQ和CHIP-SEQ方法，我们将检验MUFA合成调节炎症功能的假设 通过特定地控制cRel和重新编程表观基因组。具体目标2专注于推进 我们对巨噬细胞脂代谢重编程如何发生的理解，并确定其程度 对此，体内单核细胞和巨噬细胞的脂代谢重新编程。通过应用高级 正常、炎症和血脂异常条件下组织驻留巨噬细胞的分析技术， 我们将确定激活信号和脂环境信号是否可以诱导或塑造脂代谢 在体内重新编程。我们还进一步了解了抗炎信号或内质网应激信号是如何 被整合到新陈代谢重新编程的过程中。具体目标3是确定 SCD酶对小鼠血脂异常、慢性炎症和动脉粥样硬化的影响。SCD蛋白已经被 据报道，它既能增强动脉粥样硬化，又能抑制动脉粥样硬化。我们怀疑这是由于复杂的因素造成的 有多个SCD。在这个目标中，我们询问SCD1和SCD2的联合丢失是否在巨噬细胞中具有特异性 加重炎症、血脂异常和动脉粥样硬化。相反，可以在中强制SCD表达式 单核细胞和巨噬细胞对疾病具有保护作用。同样，失去cRel是否可以缓解炎症和 西方饮食导致动脉粥样硬化的形成。我们期望我们拟议的研究将在一个 分子水平，为什么巨噬细胞脂平衡失调导致炎症，以及炎症是如何 影响心血管疾病中的巨噬细胞胆固醇代谢。

R01: Investigating the impact of a fatty acid–cRel inflammatory circuit in atherosclerosis ABSTRACT/SUMMARY The objective of this grant to is to understand how inflammation and lipid metabolism are linked via circuits within macrophages, and whether these circuits influence cardiometabolic disease. Although perturbations in lipid homeostasis are recognized to be associated with inflammation in a number of human diseases, our understanding of “how” and “why” the processes are intimately linked remains limited. Recent work has revealed that pro-inflammatory signals can reprogram the lipid metabolic state of macrophages. It has also become clear that perturbations in lipid homeostasis can be sensed by the inflammatory machinery of macrophages so as to induce and to regulate inflammatory responses. Thus, lipid homeostasis and inflammation are interconnected, and perturbations in one affect the other. In this proposal, we combine advanced analytical mass spectrometry– based approaches with genetic models of inflammation, with the goal of defining mechanisms by which inflammation drives reprogramming of the lipidome (and vice versa). Specific Aim 1 is to determine the mechanisms by which alterations in monounsaturated fatty acid (MUFA) homeostasis regulate inflammation in activated macrophages. Specifically, we will pursue our discovery that blocking de novo MUFA synthesis potentiates inflammatory responses via the NF-κB member cRel. Using a combination of transcriptomics, ATAC- Seq, and ChIP-Seq approaches, we will test the hypothesis that MUFA synthesis regulates inflammatory function by specifically controlling cRel and the reprogramming the epigenome. Specific Aim 2 is focused on advancing our understanding of how reprogramming of lipid metabolism occurs in macrophages, and determining the extent to which reprogramming of lipid metabolism in monocytes and macrophages in vivo. By applying advanced analytic techniques on tissue resident macrophages under normal, inflammatory and dyslipidemic conditions, we will determine whether activation signals and lipid environmental cues can induce or shape lipid metabolic reprogramming in vivo. We also further our understanding of how anti-inflammatory signals or ER stress signals are integrated into this process of metabolic reprogramming. Specific Aim 3 is to determine the impact of the SCD enzymes on dyslipidemia, chronic inflammation, and atherosclerosis in mice. The SCD proteins have been reported to both potentiate and attenuate atherogenesis. We suspect this is due to the complicating factor that there are multiple SCDs. In this aim, we ask if the combined loss of SCD1 and SCD2 specifically in macrophages exacerbate inflammation, dyslipidemia and atherogenesis. Conversely, can enforced SCD expression in monocytes and macrophages protect from disease. Likewise, does loss of cRel ameliorate inflammation and atheroma formation in response to western diet. It is our expectation that our proposed studies will define, at a molecular level, why dysregulation of macrophage lipid homeostasis drives inflammation, and how inflammation influences macrophage cholesterol metabolism in cardiovascular disease.