Neuroendocrine Actions of Androgens in Female Reproduction

雄激素在女性生殖中的神经内分泌作用

• 批准号: 8809606
• 负责人: PAMELA L MELLON
• 金额: $ 32.16万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN DIEGO
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-04-01 至 2020-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8809606
• 关键词: Address; Affect; Androgen Receptor; Androgens; Anovulation; Brain; Cells; Chronic; Disease; Endocrine System Diseases; Enzymes; Estrous Cycle; Feedback; Female; Fertility; Functional disorder; Gene Expression; Genetic; Goals; Gonadal Steroid Hormones; Gonadotropins; Hormones; Hyperandrogenism; Hypothalamic structure; In Vitro; Individual; Knowledge; Location; Luteinizing Hormone; Mediating; Modeling; Molecular Genetics; Molecular Profiling; Mus; Neuroendocrine Cell; Neurons; Neurosecretory Systems; Obesity; Ovarian; Ovulation; Phenotype; Physiologic pulse; Physiological; Physiology; Pituitary Gland; Play; Polycystic Ovary Syndrome; Progesterone; Progesterone Receptors; Receptor Signaling; Regulation; Reproduction; Reproductive Physiology; Resistance; Role; Series; Signal Transduction; System; Technology; Testing; Tissues; Transgenic Mice; Transgenic Organisms; Woman; Work; cell type; genetic manipulation; hypothalamic pituitary ovarian axis; in vivo; innovation; kisspeptin; male; mouse model; novel; public health relevance; reproductive; reproductive function; reproductive hormone; response

 DESCRIPTION (provided by applicant): Androgen receptor signaling is crucial for normal female reproduction and hyperandrogenemia is a fundamental aspect of the reproductive disruption seen in Polycystic Ovary Syndrome (PCOS). Either lack of androgen receptor or androgen excess disrupts normal ovulation and neuroendocrine control of female reproduction, but the mechanisms for these effects are unknown. Our overall hypotheses are: 1) androgens acting in the brain and pituitary play an important role in regulating normal female fertility, and2) excess androgens, acting through androgen receptor in the hypothalamus and pituitary, are responsible for the neuroendocrine hallmarks of PCOS: high LH, low FSH, and progesterone (P4) resistance. We will test these hypotheses in a series of three independent but interrelated Aims that focus on the role of physiological androgen signaling and androgen excess in the hypothalamus and pituitary, using a combination of genetic and androgen-excess mouse models. Approaches will utilize genetic manipulation of androgen and P4 signaling in specific cell types in normal female mice and in a novel mouse model of obese PCOS. Aim 1 will focus on the brain by assessing whether androgen receptor (AR) is required specifically in neurons for normal female reproduction and for the deleterious effects of androgen excess. Using Cre-loxP technology, AR will be selectively deleted from brain neurons, and subsequently specifically from kisspeptin neurons. Females lacking AR in these neurons will be investigated for resistance to the effects of androgen excess in the new PCOS mouse model. Aim 2 will focus on the pituitary, with the hypothesis that excess androgens act directly at the gonadotrope to dysregulate LHβ and FSHβ and gonadotropin secretion in females. Female mice lacking AR selectively in the gonadotrope will be studied for altered reproductive function and gonadotropin secretion and in response to excess androgens in the PCOS mouse model. We will use primary pituitary cells in an innovative GnRH pulse system to directly test the actions of androgens on basal and GnRH-induced pulses of LH and FSH and gonadotropin gene expression. Aim 3 will test whether androgen excess interferes with P4 feedback at the hypothalamus and pituitary, as one attribute of PCOS women is impaired P4 feedback. We will determine if progesterone receptor (PR) is regulated by androgen excess in neuroendocrine tissues and whether P4 feedback is impaired by the actions of excess androgens. We will then remove PR selectively from brain neurons, kisspeptin neurons, or pituitary gonadotropes to investigate which cells mediate P4 negative feedback and the alterations caused by androgen excess. Together, these Aims will elucidate the role of AR and PR in the neuroendocrine system in normal female reproduction and illuminate the role of excess androgens in the dysregulation of neuroendocrine control of reproduction.

 描述（由申请人提供）：雄激素受体信号传导对于正常女性生殖至关重要，高雄激素血症是多囊卵巢综合症（PCOS）中生殖破坏的一个基本方面，雄激素受体缺乏或雄激素过多会破坏正常排卵和神经内分泌控制。女性生殖，但这些影响的机制尚不清楚，我们的总体假设是：1）作用于大脑和垂体的雄激素在调节正常方面发挥着重要作用。女性生育能力，以及 2) 过多的雄激素通过下丘脑和垂体中的雄激素受体发挥作用，导致了 PCOS 的神经内分泌特征：高 LH、低 FSH 和黄体酮 (P4) 抵抗。我们将通过三个系列来检验这些假设。独立但相互关联的目标，结合遗传和雄激素过量，重点关注下丘脑和垂体中生理雄激素信号传导和雄激素过量的作用方法将在正常雌性小鼠的特定细胞类型中利用雄激素和 P4 信号传导的基因操作，而在肥胖 PCOS 的新型小鼠模型中，目标 1 将通过评估雄激素受体 (AR) 是否是特定的需要来关注大脑。使用 Cre-loxP 技术，AR 将被选择性地从大脑神经元中删除，随后将专门研究这些神经元中缺乏 AR 的雌性神经元的抵抗力。新的 PCOS 小鼠模型中雄激素过多的影响将集中在垂体上，假设过量的雄激素直接作用于促性腺激素，导致促性腺激素选择性缺乏的雌性雌性小鼠的 LHβ 和 FSHβ 以及促性腺激素分泌失调。我们将在 PCOS 小鼠模型中研究生殖功能和促性腺激素分泌的改变以及对过量雄激素的反应。一种创新的 GnRH 脉冲系统，可直接测试雄激素对基础和 GnRH 诱导的 LH 和 FSH 脉冲以及促性腺激素基因表达的作用，Aim 3 将测试雄激素过量是否会干扰下丘脑和垂体的 P4 反馈，这是 PCOS 的一个属性。我们将确定孕激素受体 (PR) 是否受到神经内分泌组织中雄激素过多的调节以及 P4 反馈是否受到这些作用的损害。然后，我们将选择性地从大脑神经元、Kisspeptin 神经元或垂体促性腺激素中去除 PR，以研究哪些细胞介导 P4 负反馈以及雄激素过量引起的改变，这些目标将阐明 AR 和 PR 在雄激素过量中的作用。正常女性生殖中的神经内分泌系统，并阐明了过量雄激素在生殖神经内分泌控制失调中的作用。