Linking stress-associated brain and adipose functions

项目总结/摘要 急性应激通过脑基质影响能量稳态的基本机制 这些过程的两性异形性知之甚少。环境压力源会导致打架或 飞行或冻结反应通过蓝斑（LC）在脑干，一个主要的交感神经调节器， 人类和动物的能量代谢。LC支配棕色脂肪组织（BAT）， 表达高水平的神经肽PACAP（垂体腺苷酸环化酶激活剂）的PAC 1受体 肽）。PACAP/PAC 1是所有类型的应激源，恐惧，食欲，进食和能量的关键调节器 代谢和遗传与压力相关的疾病，如创伤后应激障碍（PTSD）在人类。 有趣的是，患有创伤后应激障碍的女性血液中这种神经肽和大脑PAC 1受体的水平很高， 在动物中以两性异形的方式调节恐惧。为了测试PAC 1在急性高强度脑梗死中的重要性， 压力和能量稳态，我们在小鼠中使用了压力增强的恐惧学习（SEFL）行为模型。 我们的初步数据表明，从LC消融PAC 1受体可增强SEFL表达，能量消耗， 通过间接量热法测量评估代谢，并增加代谢基因，如解偶联 蛋白1在BAT中的女性高于男性。因此，利用PAC1受体的生物学，我们的目标是奠定一个 在一个系统的和性别依赖的机制框架连接急性强烈压力和能量代谢 通过LC的方式。我们假设LC中的PAC 1受体对于门控应激相关的 代谢信息和BAT功能的性别二态性的方式。目标1将测试SEFL介导的损失 LC-PAC 1对全身能量消耗和BAT功能的作用。为此，我们将测试病毒 cre-重组酶介导的PAC 1从LC中缺失，在具有floxed PAC 1的小鼠中调节SEFL相关的 BAT中产热基因的能量消耗和诱导以性别依赖的方式（通过转录 分析、线粒体生物能量学和组织脂解）。目的2将测试表达LC神经元的PAC 1是否 在SEFL下，以两性异形的方式直接投射到BAT。为此，我们将使用逆行病毒追踪 结合LC中PAC 1的原位杂交，确定LC向BAT投射的细胞群。我们 预测雌性小鼠将表现出增强的能量消耗、BAT产热和增加的LC 投影到BAT。总的来说，使用最先进的工具和技术以及严格的系统生物学方法 我们的研究将为未来的几项研究奠定重要的基础， 工作这将作为研究慢性应激中代谢的中枢交感神经控制的前提- 与代谢性疾病共病的相关疾病，如创伤后应激障碍， 美国人口。

PROJECT SUMMARY/ABSTRACT The fundamental mechanisms by which acute intense stress affects energy homeostasis via brain substrates and sexual dimorphism of these processes are poorly understood. Environmental stressors induce fight-or- flight-or-freeze response via the locus coeruleus (LC) in the brainstem, a major sympathetic regulator in humans and animals that triggers energy metabolism. LC innervates the brown adipose tissue (BAT) and expresses high levels of PAC1 receptor for the neuropeptide PACAP (pituitary adenylate cyclase activating peptide). PACAP/PAC1 are critical regulators of stressors of all kinds, fear, appetite, feeding, and energy metabolism and genetically linked to stress-related disorders like post-traumatic stress (PTSD) in humans. Intriguingly, women with PTSD showing high blood levels of this neuropeptide and brain PAC1 receptors regulate fear in a sexually dimorphic manner in animals. To test the importance of PAC1 in acute intense stress and energy homeostasis, we used the stress-enhanced fear learning (SEFL) behavioral model in mice. Our preliminary data show that ablation of PAC1 receptors from the LC enhances SEFL expression, energy metabolism as assessed by indirect calorimetry measurement, and increases metabolic genes like uncoupling protein 1 in BAT in females than males. Thus, harnessing on the biology of PAC1 receptors, we aim to lay a mechanistic framework linking acute intense stress and energy metabolism in a systematic and sex-dependent manner via the LC. We hypothesize that PAC1 receptors in the LC are important for gating stress-associated metabolic information and BAT functions in a sexually dimorphic manner. Aim 1 will test a SEFL mediated loss of function of LC-PAC1 on whole body energy expenditure and on BAT functions. For this, we will test if viral cre-recombinase mediated PAC1 deletion from LC in mice with floxed PAC1 regulates SEFL-associated energy expenditure and induction of thermogenic genes in BAT in a sex-dependent manner (via transcript analysis, mitochondrial bioenergetics, and tissue lipolysis). Aim 2 will test if PAC1 expressing LC neurons project directly to BAT in a sexually dimorphic manner under SEFL. For this, we will use retrograde viral tracing to determine LC to BAT projecting cell populations combined with in situ hybridization for PAC1 in LC. We predict that female mice will show enhanced energy expenditure, BAT thermogenesis and increased LC projection to BAT. Overall, using state-of-the-art tools and techniques and rigorous systems biology approach of linking acute intense stress and energy metabolism, our studies will lay crucial groundwork for several future work. This will serve as a premise for studying central sympathetic control of metabolism in chronic stress- related conditions such as PTSD that are comorbid with metabolic diseases and increasingly prevalent in the US populations.