Sex Steroids, Kisspeptin and Regulation of GnRH

性类固醇、Kisspeptin 和 GnRH 的调节

基本信息

批准号：
10613337
负责人：
Jon E Levine
金额：
$ 46.52万
依托单位：
RUTGERS BIOMEDICAL AND HEALTH SCIENCES
依托单位国家：
美国
项目类别：
财政年份：
2020
资助国家：
美国
起止时间：
2020-06-01 至 2025-03-31
项目状态：
未结题

来源：
https://reporter.nih.gov/project-details/10613337
关键词：
Acceleration Adult Adult Children Alleles Animal Model Animals Axon Blood Vessels Brain Breeding Cell Nucleus Cells Central Nervous System Defect Delayed Puberty Development Doxycycline Dynorphins ESR1 gene ESR2 gene Elements Enterobacteria phage P1 Cre recombinase Estradiol Estrogen Receptor alpha Feedback Female Fertility Fertility Disorders Follicle Stimulating Hormone GNRH1 gene Gene Deletion Generations Genetic Genetic Recombination Gonadal Steroid Hormones Gonadotropin Hormone Releasing Hormone Gonadotropins Hormone secretion Hypothalamic structure Impairment Infertility Internal Ribosome Entry Site Intervention KISS1 gene Knock-out Laboratories Luteinizing Hormone Mediating Methodology Modeling Mus Neurokinin B Neurons Neuropeptides Neurosecretion Neurosecretory Systems Optics Partner in relationship Pattern Peptides Periodicity Phenotype Physiologic pulse Play Polycystic Ovary Syndrome Population Precocious Puberty Process Puberty Regulation Role Steroid Receptors Steroids Structure of nucleus infundibularis hypothalami Synapses System TACR3 gene Testing Ventricular autocrine dynorphin receptor functional hypothalamic amenorrhea gonad function inducible Cre innovation kappa opioid receptors knockout gene male mature animal median eminence mouse model neuromechanism novel paracrine preoptic nucleus prodynorphin receptor receptor binding reproductive reproductive axis reproductive function reproductive system disorder tool

项目摘要

Project Summary The central nervous system regulates gonadotropin secretion through neurosecretion of gonadotropin- releasing hormone (GnRH). GnRH is synthesized in preoptic and periventricular neurons, transported via intertwined processes that distribute as axonal-vascular terminals in the median eminence and released into the hypothalamic-hypophysial portal vasculature. GnRH binds receptors on gonadotropes to stimulate secretion and synthesis of luteinizing hormone (LH) and follicle-stimulating hormone (FSH). Neurosecretion of GnRH is pulsatile and is obligatory for sustaining normal gonadotropin secretion and synthesis. Kisspeptin (KISS1) neurons are a major GnRH afferent network that activates GnRH neurons during puberty, maintains GnRH release during adulthood, and transduces negative and positive feedback actions of gonadal steroids. In our studies we will test the hypothesis that KISS1 neurons, specifically those in the arcuate nucleus (ARC) that co-express the peptides neurokinin B (NKB) and prodynorphin (PDyn) (KNDy neurons), function as a GnRH pulse generator (Aim 1), with NKB mediating synchronized activation of KNDy cells (Aim 2) and dynorphin terminating each pulse discharge (Aim 3). These studies are significant because they will provide information on the cellular circuitries that govern GnRH pulse generation, and thus will shed new light on the pathophysiologic mechanisms underlying neuroendocrine-based fertility disorders, such as absent, delayed, or precocious puberty, functional hypothalamic amenorrhea, or polycystic ovary syndrome, and in the longer term, point to new potential targets for intervention in these reproductive impairments. The proposed studies will use powerful genetic tools to dissect and characterize the functional components of the kisspeptin-GnRH pulse generating system. To define the key elements of the pulse generator, we will utilize innovative genetically modified mouse models, each enabling an analysis of the consequences of kisspeptin neuron-specific gene deletion. We will first study the role of the KNDy neuronal population using a Kiss1fl/fl mouse recently created in our laboratory. This mouse will be bred to a prodynorphin Cre (Pdyn-IRES- Cre21,2) mouse, hereafter Pdyn-Cre, to eliminate Kiss1 in KNDy neurons. We have also developed a novel mouse bearing a doxycycline-inducible kisspeptin-Cre allele (iKiss-Cre mouse) that will enable temporal control over the selective deletion of genes from Kiss1 neurons. Two other lines, a NKBfl/fl mouse (developed in our laboratory) and an Oprk1fl/fl mouse (Jackson labs) will be crossed to Kiss1-Cre or iKiss-Cre mice to generate mice that will allow us to analyze the effects of kisspeptin neuron-specific deletion of NKB and Oprk1 on GnRH- triggered LH pulses. We will also use the iKiss-Cre mouse to delete and study the roles of steroid receptors in kisspeptin neurons in the adult. This temporally controlled gene deletion will eliminate a longstanding technical limitation of conventional steroid receptor knockout models in which steroid regulation of the axis is confounded by steroid developmental and organizational effects in the axis.

项目摘要中枢神经系统通过促性腺激素神经分泌 - 释放激素（GNRH）。 GnRH是在上型和脑室神经元中合成的，该神经元通过交织的过程在中位数中以轴突 - 血管末端分布并释放到该过程中下丘脑 - 型植物门户脉管系统。 GNRH结合促性腺激素上的受体，以刺激分泌和黄体生成激素（LH）和刺激激素（FSH）的合成。 GNRH的神经分泌是脉动，对于维持正常的促性腺激素分泌和合成是必不可少的。 Kisspeptin（kiss1）神经元是一个主要的GNRH传入网络，在激活GnRH神经元期间青春期，在成年期间保持GNRH释放，并传递负面和积极的反馈动作性腺类固醇。在我们的研究中，我们将检验以下假设：KISS1神经元，特别是弧形中的神经元核（ARC）共表达肽神经蛋白B（NKB）和Prodynorphin（PDYN）（KNDY神经元），充当GNRH脉冲发生器（AIM 1），NKB介导KNDY细胞的同步激活（AIM 2）和Dynorphin终止每个脉冲放电（AIM 3）。这些研究很重要，因为它们将提供有关控制GNRH脉冲产生的细胞电路的信息，因此将为基于神经内分泌的生育障碍，例如缺乏，延迟或早熟的青春期，功能下丘脑闭经或多囊卵巢综合征，从长远来看指出干预这些生殖障碍的新潜在目标。拟议的研究将使用强大的遗传工具来剖析和表征功能 Kisspeptin-GNRH脉冲生成系统的组件。为了定义脉冲发生器的关键元素，我们将利用创新的转基因小鼠模型，每种模型都可以分析的后果 Kisspeptin特异性基因缺失。我们将使用A首先研究Kndy神经元种群的作用 KISS1FL/FL鼠标最近在我们的实验室中创建。该小鼠将繁殖到prodynorphin cre（pdyn-ires- CRE21,2）鼠标，以下是pdyn-cre，以消除kndy神经元中的Kiss1。我们还开发了一本小说带有强力霉素诱导的亲吻蛋白-CRE等位基因（ikiss-cre鼠标）的鼠标，将实现时间控制从KISS1神经元中选择性删除基因。另外两条线是NKBFL/FL鼠标（在我们的实验室）和OPRK1FL/FL鼠标（Jackson Labs）将被交叉至Kiss1-Cre或Ikiss-Cre小鼠生成这将使我们能够分析NKB和OPRK1的Kisspeptin特异性缺失对GnRH-的影响触发LH脉冲。我们还将使用Ikiss-Cre小鼠删除和研究类固醇受体在成年人的亲吻肽神经元。该暂时控制的基因删除将消除长期的技术常规类固醇受体敲除模型的限制，其中轴的类固醇调节被混淆通过类固醇发育和组织效应。