Nutritional Regulation of Luteinizing Hormone Secretion

项目摘要 这项拟议研究的长期目标是确定 营养不良和营养状况通过调节促性腺激素释放影响生殖 公羊和母羊作为动物的激素(GnRH)和黄体生成素(LH)的分泌 模特。青春期的开始整合了各种内部和外部的线索，导致增加了对 来自下丘脑的促性腺激素释放激素，具有性成熟和生殖成功的能力。 能量摄入不足(营养不良)对促性腺激素释放激素有重大负面影响，随后 分泌黄体生成素，从而延缓青春期的开始。然而，负责该计划的中央机制 营养不良时促性腺激素释放激素/促黄体生成素分泌受到抑制或促性腺激素释放激素/促黄体生成素分泌增加 重新喂养(实现)在很大程度上仍然是未知的。因此，这项建议的目标是1)至 确定AgRP信号在调节促性腺激素释放激素和Kispeptin神经元中的作用 2)确定小胶质细胞在调节GnRH和GnRH中所起的作用。 Kispeptin神经元在营养不良和实现过程中的作用。在目标1中，我们将描述以下方面的变化 饲料限制(FR)绵羊GnRH和Kispeptin神经元中AgRP信号的体内效应 下丘脑弓状核AgRP免疫中和作用对FR促黄体生成素分泌的影响 并描述了绵羊促性腺激素释放激素和Kispeptin神经元中AgRP信号的变化。在……里面 目的2研究促性腺激素释放激素(GnRH)和促肾上腺皮质激素释放激素(FR)中Kispeptin神经元中枢免疫信号的变化 绵羊体内中枢输注白介素1受体拮抗剂对促黄体生成素分泌的影响 在FR绵羊中，表征REED中GnRH和Kispeptin神经元中枢免疫信号的变化 并检测低糖和胰岛素对小胶质细胞表型和功能的影响。 在此，凭借我们在全动物生理学、体内给药、免疫组织化学和 体外细胞培养我们设计了一些实验，以应用高度创新的荧光技术 原位杂交分析，RNAScope，用于检测AgRP的信号成分(AIM 1)和 白介素1β(Aim 2)。拟议中的实验将不仅涉及神经网络，通过 代谢状态的变化影响生殖，但也为了解免疫的作用提供了重要的见解 系统可能会运行。因此，这项工作将更好地理解营养不良的影响。 调节促性腺激素释放激素/黄体生成素分泌的中央网络，并产生新的和关键的洞察力，可能允许 更好地控制青春期的时间，并最终通过预防 与青春期延迟有关的疾病(如心血管疾病和抑郁症)。

Project Summary The long-term goal of the proposed research is to determine the central mechanisms by which undernutrition and realimentation impact reproduction through regulation of gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) secretion, using male and female sheep as an animal model. Puberty onset integrates various internal and external cues resulting in an increased release of GnRH from the hypothalamus that imparts the capacity for sexual maturation and reproductive success. Inadequate energy intake (undernutrition) has a significant negative impact on GnRH, and subsequently LH secretion, thereby delaying puberty onset. However, the central mechanisms responsible for the suppression of GnRH/LH secretion during undernutrition or the increase of GnRH/LH secretion following re-feeding (realimentation) remain largely unknown. Thus, the objectives of this proposal are 1) to determine the role that AgRP signaling plays in regulating GnRH and kisspeptin neurons during undernutrition and realimentation, and 2) to determine the role that microglia play in regulating GnRH and kisspeptin neurons during undernutrition and realimentation. In Aim 1, we will characterize changes in AgRP signaling in GnRH and kisspeptin neurons in feed-restricted (FR) sheep, examine the in vivo effect of AgRP immunoneutralization in the arcuate nucleus (ARC) of the hypothalamus on LH secretion in FR sheep, and characterize changes in AgRP signaling in GnRH and kisspeptin neurons in refed sheep. In Aim 2, we will characterize changes central immune signaling in GnRH and kisspeptin neurons in FR sheep, examine the in vivo effect of central infusion of an interleukin-1 receptor antagonist on LH secretion in FR sheep, characterize changes in central immune signaling in GnRH and kisspeptin neurons in refed sheep, and examine the in vitro effect of low glucose and insulin on microglia phenotype and function. Herein, with our expertise in whole-animal physiology, in vivo drug delivery, immunohistochemistry, and in vitro cell culture we have designed experiments to apply the highly innovative technique of a fluorescent in situ hybridization assay, RNAscope, for detection of signaling components for AgRP (Aim 1) and interleukin-1β (Aim 2). The proposed experiments will not only address the neuronal networks by which changes in metabolic state impact reproduction, but also provide important insight into the role the immune system likely plays. Thus, this work will provide a greater understanding of how undernutrition impacts central networks that regulate GnRH/LH secretion and yield novel and critical insight that may allow for better control of the timing of puberty, and ultimately lead to improved human health through prevention of disorders (e.g. cardiovascular disease and depression) associated with delayed puberty.