Estrogen regulation of channels involved in the control of energy homeostasis

描述(由申请人提供)： 这项应用的长期目标是了解雌激素和环境雌激素影响下丘脑功能的机制，如能量平衡。在美国有一种肥胖症流行，了解导致肥胖表达的任何和所有因素的病因对于治疗这种疾病至关重要。因此，指导项目的目标是了解雌二醇是如何通过多种膜启动机制影响能量稳态的，这些机制包括通过雌激素反应膜GPCR(MER)控制神经元的兴奋性，以及通过ER？和MER介导的机制控制弓状神经元的基因表达。已知雌二醇通过内质网控制能量平衡？还有Mer，因为Mer的选择性配体STX可以减轻卵巢切除后的体重增加。雌二醇还通过MER改变POMC弓状神经元的兴奋性。雌激素作用的一个潜在机制是调节一种非失活的亚阈值K电流，该电流缓和POMC的兴奋性(M电流)。为了确定雌激素对M-电流的调制是否在这些效应中起作用，我将首先利用qRT-PCR技术在单细胞池和电生理学中测量油和雌激素处理的雌性POMC和NPY神经元中KCNQ/M-电流的表达和活性。其次，我将使用全细胞斑片记录来测量急性(通过MER)雌二醇处理对POMC和NPY神经元M-电流的电生理特性的影响。独立阶段将建立在指导阶段所学技术的基础上，研究膜启动的和ERE非依赖的雌激素信号在下丘脑功能中的作用，并确定环境雌激素是否在其影响中激活了这些相同的途径。第一个目的是利用野生型ERKO和ERAlphaKI/KO小鼠模型，确定ERE非依赖性信号在雌激素和双酚A对能量稳态和下丘脑基因调控中的作用。最终目的将确定双酚A对控制能量稳态的弓状POMC和NPY神经元的电生理效应。 公共卫生相关性：指导阶段可能直接影响妇女的健康(特别是由于膜雌激素受体的选择性配体STX是一种潜在的先导化合物，可用于非传统激素替代疗法和强迫症的治疗。最后，独立阶段将解决环境雌激素影响下丘脑功能的潜在机制。

DESCRIPTION (provided by applicant): The long range goal of this application is to understand the mechanisms by which estrogen and environmental estrogens affect hypothalamic functions such as energy homeostasis. There is an obesity epidemic in the US and understanding the etiology of any and all factors that contribute to expression of obesity is critical for treatment of this disorder. Therefore, the goal of the mentored projects is to understand how estradiol affects energy homeostasis through multiple membrane-initiated mechanisms that include the control of neuronal excitability through an estradiol-responsive membrane GPCR (mER) and control of gene expression in arcuate neurons through both ER?- and mER-mediated mechanisms. Estradiol is known to control energy homeostasis through ER? and mER because STX, a selective ligand for the mER, attenuates body weight gain post-ovariectomy. Estradiol also alters neuronal excitability of POMC arcuate neurons through the mER. One potential mER-mediated mechanism for the effects of estradiol is modulation of a non-inactivating, sub-threshold K+ current that tempers the excitability of POMC (M-current). To determine if modulation of the M-current by estradiol plays a role in these effects, I will first measure the expression and activity of the KCNQ/M-current in POMC and NPY neurons from oil- and estradiol-treated females using qRT-PCR in pooled single cells and electrophysiology. Second, I will measure the effects of acute (via mER) estradiol treatment on the electrophysiological properties of the M-current in POMC and NPY neurons using whole cell patch recordings. The independent phase will build on the techniques learned during the mentored phase and examine the role of membrane-initiated and ERE-independent estrogen signaling in hypothalamic functions and determine whether environmental estrogens activate these same pathways in their effects. The first aim will determine the role of ERE-independent signaling in the control of energy homeostasis and hypothalamic gene regulation by estradiol and bisphenol A using wild-type, ?ERKO and ERalpha KI/KO mice models. The final aim will determine the electrophysiological effects of bisphenol A on arcuate POMC and NPY neurons that control energy homeostasis. PUBLIC HEALTH RELEVANCE: The mentored phase may directly impact the health of women (esp. post-menopausal women) since STX, the selective ligand for the membrane estrogen receptor, is a potential lead compound for an non-traditional hormone replacement therapy and treatment of obsesity disorders. Finally, the independent phase will address the potential mechanisms that environmental estrogens can impact hypothalamic functions.