CNS Fatty Acid Metabolism in Regulation of Food Intake

中枢神经系统脂肪酸代谢在食物摄入调节中的作用

• 批准号: 7056223
• 负责人: SUSAN M AJA
• 金额: $ 13.39万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-05-01 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7056223
• 关键词: bioenergetics; carnitine palmitoyltransferase 1; fatty acid metabolism; fatty acid synthase; gene expression; genetically modified animals; high performance liquid chromatography; hypothalamus; immunocytochemistry; laboratory mouse; neurons; nutrient intake activity

DESCRIPTION (provided by applicant): The objective of the proposal is to identify behavioral and cellular mechanisms by which inhibition of fatty acid synthase (FASi) and enhanced beta-oxidation by stimulation of carnitine-palmitoyltransferase-1 (CPT-1s) alter hypothalamic energy status and adjust food intake. The candidate will (1) gain experience with primary hypothalamic neuronal cultures and acute hypothalamic explants in static incubation, (2) learn a range of biochemical assays, and (3) build upon experience with HPLC, immunohistochemistry, and mRNA detection. The training will facilitate the candidate's transition to independent research. Experiments will be conducted at the Johns Hopkins University School of Medicine. The primary mentor is Dr. Gabriele Ronnett, a neuroscientist and biochemist who uses neuronal cultures. The co-mentor is Dr. Timothy Moran, an expert in neurophysiology of feeding. The candidate will interact with an interdisciplinary team that investigates roles of fatty acid metabolism in a range of human health problems, including obesity. C75 is a FASi/CPT-1s that reduces food intake and alters gene expression for hypothalamic feeding-related neuropeptides when given centrally to rodents. We find that icv C75 decreases feeding in rats by reducing meal frequency, not size, suggesting that FASi or CPT-1s, or both, reduce drive to initiate feeding, rather than enhance satiety. C75 affects energy status in primary cultures of hypothalamic neurons, altering intracellular signaling to modulate neuropeptide production. Novel compounds selective for potent FASi or CPT-1s are available to us to investigate individual roles of FAS and CPT-1 in feeding regulation. The overall hypothesis is that altered fatty acid metabolism in hypothalamic neurons changes their energy state and leads to homeostatic alterations in food intake. Experiments will address two Specific Aims: (1) Identify how FASi or CPT-1s in the brain alter food intake and gene expression: Experiments in mice will measure food intake, meal patterns, brain c-Fos expression, and expression of mRNA for feeding-related neuropeptides after icv C75, FASi, or CPT-1s. The second aim is to (2) Identify how FASi and CPT-1s change hypothalamic neuronal energy status and production of feeding-regulating neuropeptides: The compounds will be applied to (a) primary hypothalamic neuronal cultures and (b) acute hypothalamic explants. We will measure changes in intracellular AMP/ATP ratio and activity of AMP-activated protein kinase, levels of mRNAs for feeding-related neuropeptides, and neuropeptide production and release.

描述（由申请人提供）： 该提案的目的是确定行为和细胞机制，通过该机制抑制脂肪酸合成酶（FASi）并通过刺激肉毒碱-棕榈酰转移酶-1（CPT-1 s）来增强β-氧化，从而改变下丘脑能量状态并调整食物摄入量。候选人将（1）获得原代下丘脑神经元培养和静态孵育中急性下丘脑外植体的经验，（2）学习一系列生化测定，（3）积累HPLC，免疫组织化学和mRNA检测的经验。培训将有助于候选人过渡到独立研究。实验将在约翰霍普金斯大学医学院进行。主要导师是Gabriele Ronnett博士，他是一位神经科学家和生物化学家，使用神经元培养。共同导师是蒂莫西·莫兰博士，他是喂养神经生理学专家。候选人将与一个跨学科团队互动，该团队调查脂肪酸代谢在一系列人类健康问题中的作用，包括肥胖。C75是一种FASi/CPT-1 s，当中枢给予啮齿动物时，可减少食物摄入并改变下丘脑摄食相关神经肽的基因表达。我们发现icv C75通过减少进食频率而不是大小来减少大鼠的进食，这表明FASi或CPT-1或两者都减少了开始进食的驱动力，而不是增强饱腹感。C75影响下丘脑神经元原代培养物的能量状态，改变细胞内信号传导以调节神经肽的产生。对有效的FASi或CPT-1具有选择性的新型化合物可供我们研究FAS和CPT-1在摄食调节中的个体作用。总的假设是，下丘脑神经元中脂肪酸代谢的改变改变了它们的能量状态，并导致食物摄入的稳态改变。实验将解决两个具体目标：（1）确定大脑中的FASi或CPT-1如何改变食物摄入和基因表达：小鼠实验将测量icv C75、FASi或CPT-1后的食物摄入、膳食模式、大脑c-Fos表达和进食相关神经肽的mRNA表达。第二个目的是（2）鉴定FASi和CPT-1如何改变下丘脑神经元能量状态和摄食调节神经肽的产生：将化合物应用于（a）原代下丘脑神经元培养物和（B）急性下丘脑外植体。我们将测量细胞内AMP/ATP比率和AMP活化蛋白激酶活性的变化，摄食相关神经肽的mRNA水平，以及神经肽的产生和释放。