Investigating hypothalamic kisspeptin neuronal dysfunction as a key mediator of the pathophysiology of PCOS and HA

问题：多囊卵巢综合征（PCOS）和下丘脑闭经（HA）是影响年轻女性的两种最常见的生殖疾病，分别在2-13%和1-2%的绝经前女性中发现。PCOS的特征是月经不规律、高雄激素血症和超声显示的多囊卵巢形态（PCOM），而HA的特征是低体重、过度运动和心理压力。这两种生殖疾病的关键异常是下丘脑促性腺激素释放激素（GnRH）脉动性的改变。具体来说，PCOS女性的GnRH脉动增加，而HA女性的GnRH脉动减少。下丘脑弓状核（ARC）（人类漏斗核）中的Kisspeptin（KP）神经元被认为是“GnRH脉冲发生器”。尽管ARC kisspeptin表达在大多数PCOS样模型如产前雄激素化模型中增加，但尚不清楚这种改变是否是生殖表型病因学的原因。此外，目前尚不清楚在已建立的PCOS模型（即产前雄激素化模型）中减弱kisspeptin神经元过度活动是否可以减弱PCOS样表型。相反，虽然ARC kisspeptin的表达减少HA样模型，它是不知道是否增加ARC kisspeptin神经元激活可以挽救生殖健康面临营养不良。此外，这两种情况的诊断可能是具有挑战性的。虽然这两种情况的诊断都得到了指南的支持，但这两种情况都是排除诊断，高达86%的被诊断为HA的女性也符合PCOS的诊断标准。因此，即使是具有专业知识的临床医生也可能面临对寡/闭经女性的诊断不确定性。由于下丘脑功能的改变是一个关键的，但在这些条件下不同的异常，我将评估是否下丘脑功能障碍的评估使用KP测试可以代表一个客观的方法来分类月经失调的原因，在妇女提出与寡/amnio-rhoea。确定是否恢复ARC kisspeptin-神经元激活可以挽救发情周期在HA小鼠模型。确定ARC kisspeptin-神经元活性增加是否是PCOS 2a的原因：确定在已建立的PCOS小鼠模型（产前雄激素化）中降低ARC kisspeptin-神经元过度活性是否可以解决生殖表型。 2b：确定在健康成年雌性小鼠中增加ARC kisspeptin-神经元活化是否诱导PCOS样表型。评价KP静脉推注的内分泌反应作为诊断测试，以区分PCOS和HA在寡/闭经women.Applications和好处：这项建议将建立在何种程度上的ARC kisspeptin神经元的活动的改变直接负责PCOS和HA中观察到的表型的歧视性能。此外，这些数据将建立靶向这些神经元的治疗相关性，通过确定是否减弱其在产前雄激素化的PCOS样模型中的过度活跃，或增加其在HA模型中，可以解决生殖健康的障碍。KP是下丘脑GnRH分泌的有效刺激物，因此可以用于评估下丘脑功能。我的试验数据表明，与PCOS患者相比，HA患者的促黄体生成激素（LH）反应被夸大了。因此，下丘脑功能的KP测试可以发展成为一个客观的测试，以确定在妇女提出寡/ampliferoea.Summary的原因：这一建议的总体目标是调查的作用下丘脑弓状kisspeptin神经元活动的PCOS和HA的病因，并确定KP作为诊断测试的妇女月经紊乱的实用程序。

Problem: Polycystic Ovary Syndrome (PCOS) and Hypothalamic Amenorrhoea (HA) are the two commonest reproductive disorders affecting young women, being found in 2-13% and 1-2% of pre-menopausal women, respectively. PCOS is characterised by menstrual irregularity, hyperandrogenism and polycystic ovarian morphology on ultrasound (PCOM), whereas HA by low body-weight, excessive exercise and psychological stress. A key abnormality in both of these reproductive disorders is the alteration in hypothalamic gonadotrophin releasing hormone (GnRH) pulsatility. Specifically, women with PCOS have increased GnRH pulsatility, whereas women with HA have reduced GnRH pulsatility. Kisspeptin (KP) neurons in the arcuate (ARC) nucleus of the hypothalamus (infundibular nucleus in humans) are thought to be the 'GnRH pulse generator'. Although ARC kisspeptin expression is increased in most PCOS-like models eg prenatal androgenised model, it is not known whether this alteration is causal in the aetiology of the reproductive phenotype. Furthermore, it is not known whether attenuating kisspeptin neuronal overactivity in an established model of PCOS (ie prenatal androgenised model) can attenuate the PCOS-like phenotype. Conversely, although ARC kisspeptin expression is reduced in HA-like models, it is not known whether increasing ARC kisspeptin neuronal activation can rescue reproductive health in the face of undernutrition.Furthermore, the diagnosis of both conditions can be challenging. Whilst the diagnosis of both conditions is supported by guidelines, both conditions are diagnoses of exclusion and up to 86% of women diagnosed as HA also meet diagnostic criteria for PCOS. Thus, even clinicians with specialist expertise may be faced with diagnostic uncertainty in women presenting with oligo/amenorrhoea. As the alteration in hypothalamic function is a key but divergent abnormality in these conditions, I will evaluate whether assessment of hypothalamic dysfunction using a KP test could represent an objective method to classify the cause of menstrual disturbance in women presenting with oligo/amenorrhoea.Aims:1. Determine whether restoring ARC kisspeptin-neuronal activation can rescue estrus cyclicity in a mouse model of HA.2. Determine whether increased ARC kisspeptin-neuronal activity is responsible for PCOS 2a: Establish whether reducing ARC kisspeptin-neuronal overactivity in an established mouse model of PCOS (prenatal androgenised) can resolve the reproductive phenotype. 2b: Determine whether increasing ARC kisspeptin-neuronal activation in healthy adult female mice induces a PCOS-like phenotype.3. Evaluate the discriminatory performance of the endocrine response to an intravenous bolus of KP as a diagnostic test to differentiate PCOS and HA in oligo/amenorrhoeic women.Applications and Benefits: This proposal will establish the extent to which alterations in the activity of ARC kisspeptin neurons are directly responsible for the phenotype observed in PCOS and HA. Moreover, these data will establish the therapeutic relevance of targeting these neurons by determining whether attenuating their overactivity in a prenatal androgenised PCOS-like model, or increasing it in a HA model, can resolve the disturbance in reproductive health.KP is a potent stimulator of hypothalamic GnRH secretion, and thus can be used to assess hypothalamic function. My pilot data demonstrates that the luteinising hormone (LH) response is exaggerated in women with HA, compared to those with PCOS. Thus, a KP test of hypothalamic function could be developed into an objective test to identify the cause in women presenting with oligo/amenorrhoea.Summary:The overall aim of this proposal is to investigate the role of hypothalamic arcuate kisspeptin neuronal activity in the aetiology of PCOS and HA, and to determine the utility of KP as a diagnostic test in women presenting with menstrual disturbance.