hypothalamus

下丘脑
  • 文章类型: Journal Article
    青春期的开始,在下丘脑-垂体-性腺(HPG)轴的控制下,受各种因素的影响,包括肥胖,这与青春期的早期发作有关。肥胖诱导的下丘脑炎症可能导致促性腺激素释放激素(GnRH)神经元过早激活,导致早熟或早熟的发展。涉及phoenixin作用和下丘脑小胶质细胞的机制。此外,肥胖会导致大脑结构和细胞改变,扰乱代谢调节。影像学研究揭示了肥胖个体的神经炎症变化,影响青春期的时间。磁共振波谱能够通过测量关键代谢物来评估大脑的神经化学成分,强调与肥胖相关的神经系统变化的潜在途径。在这篇文章中,我们提供的证据表明肥胖之间存在潜在的关联,下丘脑炎症,和性早熟.
    The onset of puberty, which is under the control of the hypothalamic-pituitary-gonadal (HPG) axis, is influenced by various factors, including obesity, which has been associated with the earlier onset of puberty. Obesity-induced hypothalamic inflammation may cause premature activation of gonadotropin-releasing hormone (GnRH) neurons, resulting in the development of precocious or early puberty. Mechanisms involving phoenixin action and hypothalamic microglial cells are implicated. Furthermore, obesity induces structural and cellular brain alterations, disrupting metabolic regulation. Imaging studies reveal neuroinflammatory changes in obese individuals, impacting pubertal timing. Magnetic resonance spectroscopy enables the assessment of the brain\'s neurochemical composition by measuring key metabolites, highlighting potential pathways involved in neurological changes associated with obesity. In this article, we present evidence indicating a potential association among obesity, hypothalamic inflammation, and precocious puberty.
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  • 文章类型: Journal Article
    下丘脑-垂体轴是神经内分泌系统功能的核心,对于调节生理和行为稳态以及协调基本身体功能至关重要。越来越多的证据表明,microRNA途径在调节发育中和成年下丘脑和垂体的基因表达谱中发挥着不可或缺的作用。在下丘脑-垂体轴的背景下引起miRNA成熟耗尽的实验引起了神经内分泌功能中miRNA的突出参与。还有一些单独的miRNA和miRNA家族已经被深入研究,揭示了它们在调节基本过程中的关键作用,例如青春期时间的时间精度。激素产生,生育能力和繁殖力,和能量平衡。在这些miRNA中,miR-7被证明是富含下丘脑的,并且在垂体中高度表达,它对基因表达调控有深远的影响。这里,我们回顾了miRNA谱,敲除表型,和下丘脑-垂体轴中的miRNA相互作用(靶标)促进了我们对miRNA在哺乳动物神经分泌和相关生理学中的作用的理解。
    The hypothalamic-pituitary axis is central to the functioning of the neuroendocrine system and essential for regulating physiological and behavioral homeostasis and coordinating fundamental body functions. The expanding line of evidence shows the indispensable role of the microRNA pathway in regulating the gene expression profile in the developing and adult hypothalamus and pituitary gland. Experiments provoking a depletion of miRNA maturation in the context of the hypothalamic-pituitary axis brought into focus a prominent involvement of miRNAs in neuroendocrine functions. There are also a few individual miRNAs and miRNA families that have been studied in depth revealing their crucial role in mediating the regulation of fundamental processes such as temporal precision of puberty timing, hormone production, fertility and reproduction capacity, and energy balance. Among these miRNAs, miR-7 was shown to be hypothalamus-enriched and the top one highly expressed in the pituitary gland, where it has a profound impact on gene expression regulation. Here, we review miRNA profiles, knockout phenotypes, and miRNA interaction (targets) in the hypothalamic-pituitary axis that advance our understanding of the roles of miRNAs in mammalian neurosecretion and related physiology.
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  • 文章类型: Journal Article
    小儿视路/下丘脑胶质瘤(OPHG)由于其位置和与重要结构的接近性而在治疗中提出了挑战。手术切除在OPHG的治疗中起着关键作用,尤其是当肿瘤表现出肿块效应并引起症状时。然而,关于OPHG手术切除结果和并发症的数据仍然不一致.作者在四个数据库中对儿科OPHG进行了系统评价:PubMed,EMBASE,科克伦图书馆,谷歌学者。我们纳入了有关OPHG切除术的视觉结果和并发症的研究。根据系统评价和荟萃分析(PRISMA)声明的首选报告项目进行荟萃分析并报告。共纳入26项回顾性研究。检查了797例接受手术切除的OPHG儿科患者。在9.7%中确认了NF1的诊断。总切除率为36.7%。与位于交叉/下丘脑区域的患者相比,眶内视路胶质瘤显示出明显更高的总切除率(75.8%vs.9.6%)。术后,视力提高了24.6%,68.2%保持不变,恶化为18.2%。并发症包括脑积水(35.4%),垂体前叶功能障碍(19.6%),短暂性尿崩症(29%)。切除后肿瘤进展发生率为12.8%,平均随访53.5个月。手术切除仍然是治疗症状性和大型小儿OPHG的重要策略,并且可以在大多数患者中产生良好的视力结果。仔细选择病人是至关重要的。术后应监测患者脑积水的发展,并随访以评估肿瘤进展和辅助治疗的必要性。
    Pediatric optic pathway/hypothalamic gliomas (OPHG) pose challenges in treatment due to their location and proximity to vital structures. Surgical resection plays a key role in the management of OPHG especially when the tumor exhibits mass effect and causes symptoms. However, data regarding outcomes and complications of surgical resection for OPHG remains heterogenous. The authors performed a systematic review on pediatric OPHG in four databases: PubMed, EMBASE, Cochrane Library, and Google Scholar. We included studies that reported on the visual outcomes and complications of OPHG resection. A meta-analysis was performed and reported per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A total of 26 retrospective studies were included. Seven hundred ninety-seven pediatric patients with OPHG undergoing surgical resection were examined. A diagnosis of NF1 was confirmed in 9.7%. Gross total resection was achieved in 36.7%. Intraorbital optic pathway gliomas showed a significantly higher gross total resection rate compared to those located in the chiasmatic/hypothalamic region (75.8% vs. 9.6%). Postoperatively, visual acuity improved in 24.6%, remained unchanged in 68.2%, and worsened in 18.2%. Complications included hydrocephalus (35.4%), anterior pituitary dysfunction (19.6%), and transient diabetes insipidus (29%). Tumor progression post-resection occurred in 12.8%, through a mean follow-up of 53.5 months. Surgical resection remains an essential strategy for treating symptomatic and large pediatric OPHG and can result in favorable vision outcomes in most patients. Careful patient selection is critical. Patients should be monitored for hydrocephalus development postoperatively and followed up to assess for tumor progression and adjuvant treatment necessity.
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  • 文章类型: Journal Article
    下丘脑肥胖代表肥胖的更广泛范围内的临床状况,其经常逃避检测和适当的诊断。肥胖的这一子集的特征在于缺乏已建立的预测性标志物和缺乏标准化的治疗方案。胰高血糖素样肽-1(GLP-1)受体激动剂在肥胖治疗领域的出现和日益突出,为下丘脑肥胖管理提供了新的治疗途径。尽管如此,在这种情况下,关于GLP-1受体(GLP-1R)激动剂的有效性的关键询问仍然存在,特别是关于它们的主要作用机制和对下丘脑肥胖的具体影响。
    在这篇叙述性评论中,我们专注于分析描述GLP-1受体在不同下丘脑和大脑区域的检测和功能的研究论文.此外,我们审查了详细介绍GLP-1受体激动剂在治疗下丘脑肥胖中应用的临床研究论文和报告.此外,我们包括来自我们单位的临床病例的简要介绍,以进行上下文理解。
    目前,支持GLP-1受体激动剂在下丘脑肥胖中疗效的临床证据,以及这种肥胖亚型的不同特征,仍然不够。初步数据表明,GLP-1R激动剂可能提供有效的治疗选择,尽管结果可变,特别是在年轻的患者队列中。从机械的角度来看,GLP-1受体在各种下丘脑和更广泛的大脑区域的存在可能支持GLP-1R激动剂的功效,即使在下丘脑损伤的情况下。然而,进一步的研究是必要的,以确定这些受体在所述脑区的功能相关性。
    GLP-1R激动剂代表了下丘脑肥胖患者的潜在治疗选择。然而,进一步的临床和基础/转化研究对于验证这些药物在下丘脑肥胖的不同表现中的疗效以及了解GLP-1R在其表达的不同脑区的功能至关重要.
    UNASSIGNED: Hypothalamic obesity represents a clinical condition within the broader spectrum of obesity that frequently eludes detection and appropriate diagnosis. This subset of obesity is characterized by a dearth of established predictive markers and a paucity of standardized therapeutic protocols. The advent and rising prominence of glucagon-like peptide-1 (GLP-1) receptor agonists in the obesity treatment landscape present novel therapeutic avenues for hypothalamic obesity management. Nonetheless, critical inquiries persist concerning the efficacy of GLP-1 receptor (GLP-1R) agonists in this context, particularly regarding their central mechanisms of action and specific impact on hypothalamic obesity.
    UNASSIGNED: In this narrative review, we concentrate on analyzing research papers that delineate the detection and function of GLP-1 receptors across various hypothalamic and cerebral regions. Additionally, we examine clinical research papers and reports detailing the application of GLP-1 receptor agonists in treating hypothalamic obesity. Furthermore, we include a concise presentation of a clinical case from our unit for contextual understanding.
    UNASSIGNED: Currently, the clinical evidence supporting the efficacy of GLP-1 receptor agonists in hypothalamic obesity, as well as the diverse characteristics of this obesity subtype, remains insufficient. Preliminary data suggest that GLP-1R agonists might offer an effective treatment option, albeit with variable outcomes, particularly in younger patient cohorts. From a mechanistic perspective, the presence of GLP-1 receptors in various hypothalamic and broader brain regions potentially underpins the efficacy of GLP-1R agonists, even in instances of hypothalamic damage. Nevertheless, additional research is imperative to establish the functional relevance of these receptors in said brain regions.
    UNASSIGNED: GLP-1R agonists represent a potential therapeutic option for patients with hypothalamic obesity. However, further clinical and basic/translational research is essential to validate the efficacy of these drugs across different presentations of hypothalamic obesity and to understand the functionality of GLP-1R in the diverse brain regions where they are expressed.
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  • 文章类型: Case Reports
    弥漫性中线胶质瘤(DMG),H3K27-改变,是一种新定义的“儿科类型”,\"弥漫,世卫组织目前分类下的高级别神经胶质瘤(2021年更新)。DMG的基本诊断标准是其在中线结构中的出现;大多数颅内DMG发生在脑干或丘脑中,但也可以发生在其他中线结构中。我们在脑干和丘脑以外的区域经历了2例成人颅内DMG,最初难以诊断。病例1是一名49岁的男性,在脑MRI上双侧额叶和call体具有广泛的T2高信号病变。基于Gd的造影剂部分增强了病变,并显示出明显的弥散限制,模仿恶性淋巴瘤.病例2是一名24岁的男性,他表现出阵发性嗅觉异常。肿瘤主要延伸到右颞叶,右基底前脑,和双侧下丘脑,显示T2/FLAIR错配标志,提示没有1p/19q共缺失的IDH突变型星形细胞瘤。活检后,这两个病例都被正确诊断为DMG,H3K27-改变(K27M-突变体)。在手术前诊断涉及非典型中线结构的成人病例有时具有挑战性;我们通过病例细节和文献综述来讨论这种现象。
    Diffuse midline glioma (DMG), H3 K27-altered, is a newly defined \"pediatric-type,\" diffuse, high-grade glioma under current WHO classifications (updated in 2021). An essential diagnostic criteria of DMG is its occurrence in the midline structures; most intracranial DMG occurs in the brainstem or thalamus but can also occur in other midline structures. We experienced 2 adult cases of intracranial DMGs in areas other than the brainstem and thalamus that were initially difficult to diagnose. Case 1 was a 49-year-old man with extensive T2 high-signal lesions in the bilateral frontal lobes and corpus callosum on brain MRI. A Gd-based contrast medium partially enhanced the lesion and showed marked diffusion restriction, mimicking malignant lymphoma. Case 2 was a 24-year-old man who presented with paroxysmal olfactory abnormalities. The tumor extended mainly to the right temporal lobe, the right basal forebrain, and the bilateral hypothalamus, showing a T2/FLAIR mismatch sign suggestive of IDH-mutant astrocytoma without 1p/19q co-deletion. After a biopsy, both cases were properly diagnosed as DMG, H3 K27-altered (K27M-mutant). Diagnosing adult cases involving atypical midline structures is sometimes challenging before surgery; we discuss this phenomenon with both case details and a literature review.
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  • 文章类型: Case Reports
    慢性丛集性头痛(CCH)是一种使人衰弱的原发性头痛,可引起剧烈的疼痛而无法缓解。多年来实施了各种医疗和手术治疗,然而,许多人只提供短期救济。深部脑刺激(DBS)是一种新兴的治疗方法,已被证明可以显着降低头痛发作的强度和频率。然而,CCHDBS后超过10年结果的报告很少。这里,我们报道了1例CCH患者10年后下丘脑后下丘脑DBS的持久性.我们的患者在DBS后头痛频率下降了82%,维持了10多年。观察到的副作用包括抑郁,烦躁,焦虑,头晕,通过更改编程设置来缓解。在当前文学的背景下,当其他治疗失败时,DBS有望长期缓解丛集性头痛。
    Chronic cluster headache (CCH) is a debilitating primary headache that causes excruciating pain without remission. Various medical and surgical treatments have been implemented over the years, yet many provide only short-term relief. Deep brain stimulation (DBS) is an emerging treatment alternative that has been shown to dramatically reduce the intensity and frequency of headache attacks. However, reports of greater than 10-year outcomes after DBS for CCH are scant. Here, we report the durability of DBS in the posterior inferior hypothalamus after 10 years on a patient with CCH. Our patient experienced an 82% decrease in the frequency of headaches after DBS, which was maintained for over 10 years. The side effects observed included depression, irritability, anxiety, and dizziness, which were alleviated by changing programming settings. In the context of current literature, DBS shows promise for long-term relief of cluster headaches when other treatments fail.
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  • 文章类型: Review
    目的:Sturge-Weber综合征(SWS)是一种罕见的神经皮肤疾病,其特征是节段性皮肤区面部葡萄酒色斑胎记,并经常伴有同侧大脑和眼睛异常。我们介绍了一例SWS患者,其表现为低促性腺激素性腺功能减退,生长激素(GH)缺乏,尽管垂体和下丘脑没有影像学检查结果,但20岁时仍有中枢甲状腺功能减退症。
    方法:一名20岁男性SWS伴癫痫和Klippel-Trenaunay综合征表现为青春期发育延迟,身材矮小,和肥胖。经进一步检查,他被发现有性腺功能减退的生化和临床证据,甲状腺功能减退,和GH缺乏。垂体MRI显示垂体或下丘脑未见异常。开始用睾酮环戊酸盐和左甲状腺素治疗。尽管青春期诱导成功,IGF-1水平仍然很低,现在正在考虑用重组人生长激素(rhGH)治疗代谢益处。
    结论:本案例强调了对SWS患者进行内分泌评估和治疗激素缺乏的重要性,尽管没有影像学检查结果。
    OBJECTIVE: Sturge-Weber syndrome (SWS) is a rare neurocutaneous disorder that is characterized by a segmental dermatomal facial port-wine stain birthmark and is frequently accompanied by ipsilateral brain and eye abnormalities. We present a case of a patient with SWS who exhibited hypogonadotropic hypogonadism, growth hormone (GH) deficiency, and central hypothyroidism at the age of 20 despite the absence of radiographic findings in the pituitary and hypothalamus.
    METHODS: A 20-year-old male with SWS with epilepsy and Klippel-Trenaunay syndrome presents with delayed pubertal development, short stature, and obesity. Upon further examination, he was found to have biochemical and clinical evidence of hypogonadism, hypothyroidism, and GH deficiency. A pituitary MRI displayed no abnormalities of the pituitary or hypothalamus. Treatment with testosterone cypionate and levothyroxine was initiated. Despite successful pubertal induction, IGF-1 levels have remained low and treatment with recombinant human growth hormone (rhGH) is now being considered for metabolic benefits.
    CONCLUSIONS: This case emphasizes the importance of endocrine evaluation and treatment of hormonal deficiencies in patients with SWS despite the absence of radiographic findings.
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  • 文章类型: Journal Article
    背景:神经肽催产素(OT)在几种情况下至关重要,如哺乳,分娩,母婴互动,和心理社会功能。此外,OT可能参与饮食行为的调节。
    方法:这篇综述简要总结了有关OT在饮食行为中的作用的数据。在PubMed/MEDLINE中识别并搜索适当的关键词和医学主题词。对原始文章和评论的参考文献进行了筛选,检查,并选择。
    结果:下丘脑分泌OT的神经元投射到控制进食行为的不同大脑区域,比如杏仁核,区域后,孤束核,和迷走神经的背侧运动核。脑内/脑室OT给药可降低野生和遗传肥胖大鼠的食物摄入量和体重。OT可能会改变食物摄入量和膳食质量,尤其是碳水化合物和甜食,在人类中。
    结论:OT可能在进食障碍的病理生理学中起作用,具有潜在的治疗前景。在肥胖患者和某些饮食失调的患者中,如神经性暴食症或暴饮暴食/强迫性进食,OT可能会降低食欲和热量消耗。相反,给予神经性厌食症患者OT可能矛盾地刺激食欲,可能是通过降低焦虑,而焦虑通常会使这些患者的管理复杂化。然而,OT管理(例如,鼻内途径)并不总是与临床获益相关,可能是因为鼻内给予OT未能达到治疗性脑内水平的激素。
    结论:OT给药可以在控制饮食失调和饮食失调方面发挥治疗作用。然而,需要具体的研究来澄清剂量发现,给药途径和给药时间方面的问题.
    BACKGROUND: The neuropeptide oxytocin (OT) is crucial in several conditions, such as lactation, parturition, mother-infant interaction, and psychosocial function. Moreover, OT may be involved in the regulation of eating behaviors.
    METHODS: This review briefly summarizes data concerning the role of OT in eating behaviors. Appropriate keywords and medical subject headings were identified and searched for in PubMed/MEDLINE. References of original articles and reviews were screened, examined, and selected.
    RESULTS: Hypothalamic OT-secreting neurons project to different cerebral areas controlling eating behaviors, such as the amygdala, area postrema, nucleus of the solitary tract, and dorsal motor nucleus of the vagus nerve. Intracerebral/ventricular OT administration decreases food intake and body weight in wild and genetically obese rats. OT may alter food intake and the quality of meals, especially carbohydrates and sweets, in humans.
    CONCLUSIONS: OT may play a role in the pathophysiology of eating disorders with potential therapeutic perspectives. In obese patients and those with certain eating disorders, such as bulimia nervosa or binge/compulsive eating, OT may reduce appetite and caloric consumption. Conversely, OT administered to patients with anorexia nervosa may paradoxically stimulate appetite, possibly by lowering anxiety which usually complicates the management of these patients. Nevertheless, OT administration (e.g., intranasal route) is not always associated with clinical benefit, probably because intranasally administered OT fails to achieve therapeutic intracerebral levels of the hormone.
    CONCLUSIONS: OT administration could play a therapeutic role in managing eating disorders and disordered eating. However, specific studies are needed to clarify this issue with regard to dose-finding and route and administration time.
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  • 文章类型: Journal Article
    自从严重急性呼吸道综合症冠状病毒2(SARS-CoV-2)大流行以来,已经描述了急性期和/或长期并发症中几种内分泌异常的发生率增加。本综述的目的是对自2019年12月以来全球儿童内分泌流行病学变化的现有文献进行广泛概述,并报告支持其与2019年冠状病毒病(COVID-19)相关的证据。尽管对儿童COVID-19期间内分泌器官的参与知之甚少,目前在成人中的证据和对儿科人群的流行病学研究表明,该病毒与内分泌疾病之间存在因果关系.未经治疗的一过性甲状腺功能障碍,病态甲状腺功能正常综合征,非甲状腺疾病综合征,在急性感染和/或多系统炎症综合征发展过程中观察到下丘脑-垂体-肾上腺(HPA)轴和中枢性早熟。此外,有文献报道,在1型糖尿病新诊断的儿童中,酮症酸中毒的发生率更高。尽管COVID-19与内分泌参与之间的直接关联尚未得到证实,关于儿童不同内分泌疾病发展的数据,无论是在急性感染期间还是由于其长期并发症,已被报道。这些信息对于指导先前或当前患有COVID-19的患者的管理至关重要。
    Since the advent of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, an increased incidence of several endocrinological anomalies in acute-phase and/or long-term complications has been described. The aim of this review is to provide a broad overview of the available literature regarding changes in the worldwide epidemiology of endocrinological involvement in children since December 2019 and to report the evidence supporting its association with coronavirus disease 2019 (COVID-19). Although little is known regarding the involvement of endocrine organs during COVID-19 in children, the current evidence in adults and epidemiological studies on the pediatric population suggest the presence of a causal association between the virus and endocrinopathies. Untreated transient thyroid dysfunction, sick euthyroid syndrome, nonthyroidal illness syndrome, and hypothalamic-pituitary-adrenal (HPA) axis and central precocious puberty have been observed in children in acute infection and/or during multisystem inflammatory syndrome development. Furthermore, a higher frequency of ketoacidosis at onset in children with a new diagnosis of type 1 diabetes is reported in the literature. Although the direct association between COVID-19 and endocrinological involvement has not been confirmed yet, data on the development of different endocrinopathies in children, both during acute infection and as a result of its long-term complications, have been reported. This information is of primary importance to guide the management of patients with previous or current COVID-19.
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  • 文章类型: Journal Article
    青春期发育是一个复杂的生物学过程,涉及生殖神经内分泌轴的成熟以及促性腺激素释放激素(GnRH)和黄体生成素的脉冲释放增加。营养是控制青春期时间的关键环境因素。出生后早期发育期间的营养限制会延迟青春期,而在此期间增加的采食量和肥胖会通过印记下丘脑来加速青春期成熟。此外,妊娠期间的营养可以对发育中的胎儿神经内分泌系统进行编程,并有可能促进或延迟后代的青春期。瘦素,一种主要由脂肪细胞产生的激素,在向大脑传达能量状态和调节性成熟方面发挥着重要作用。瘦素对GnRH释放的调节是由上游神经元网络介导的,因为GnRH神经元不含瘦素受体。两组位于下丘脑弓状核的神经元表达神经肽Y(NPY),一种促食欲肽,和α黑素细胞刺激素(αMSH),一种厌食肽,是将抑制性(NPY)和兴奋性(αMSH)输入传递给GnRH神经元的神经回路的中心元素。此外,KNDy神经元,弓状核中共表达kisspeptin的神经元,神经激肽B(NKB),和强啡肽,还在青春期的代谢调节中发挥作用。我们在牛母牛中的研究表明,断奶后早期(4-9个月)BW增加率导致NPYmRNA表达降低,原黑皮质素和kisspeptin受体mRNA的表达增加,减少对GnRH神经元的NPY抑制输入,增加了对KNDy神经元的兴奋性αMSH输入。最后,我们的最新数据表明,母牛在妊娠最后两个三个月的营养也可以诱导母牛后代下丘脑神经回路的转录和结构变化,这种变化可能在出生后长期持续.管理方法,例如在妊娠期间补充大坝(胎儿编程),蠕变进料,早期断奶,已经开发了阶梯式营养方案,以利用小母牛的大脑可塑性和促进青春期成熟。
    Pubertal attainment is an intricate biological process that involves maturation of the reproductive neuroendocrine axis and increased pulsatile release of gonadotropin-releasing hormone (GnRH) and luteinizing hormone. Nutrition is a critical environmental factor controlling the timing of puberty attainment. Nutrient restriction during early postnatal development delays puberty, whereas increased feed intake and adiposity during this period hasten pubertal maturation by imprinting the hypothalamus. Moreover, the dam\'s nutrition during gestation can program the neuroendocrine system in the developing fetus and has the potential to advance or delay puberty in the offspring. Leptin, a hormone produced primarily by adipose cells, plays an important role in communicating energy status to the brain and regulating sexual maturation. Leptin\'s regulation of GnRH release is mediated by an upstream neuronal network since GnRH neurons do not contain the leptin receptor. Two groups of neurons located in the arcuate nucleus of the hypothalamus that express neuropeptide Y (NPY), an orexigenic peptide, and alpha melanocyte-stimulating hormone (αMSH), an anorexigenic peptide, are central elements of the neural circuitry that relay inhibitory (NPY) and excitatory (αMSH) inputs to GnRH neurons. Moreover, KNDy neurons, neurons in the arcuate nucleus that co-express kisspeptin, neurokinin B (NKB), and dynorphin, also play a role in the metabolic regulation of puberty. Our studies in beef heifers demonstrate that increased rates of BW gain during early postweaning (4-9 mo of age) result in reduced expression of NPY mRNA, increased expression of proopiomelanocortin and kisspeptin receptor mRNA, reduced NPY inhibitory inputs to GnRH neurons, and increased excitatory αMSH inputs to KNDy neurons. Finally, our most recent data demonstrate that nutrition of the cow during the last two trimesters of gestation can also induce transcriptional and structural changes in hypothalamic neurocircuitries in the heifer progeny that likely persist long-term after birth. Managerial approaches, such as supplementation of the dam during gestation (fetal programming), creep feeding, early weaning, and stair-step nutritional regimens have been developed to exploit brain plasticity and advance pubertal maturation in heifers.
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