Reproductive Phenotype of Adrenomedullin2 (ADM2) knockout mice

肾上腺髓质素2 (ADM2) 敲除小鼠的生殖表型

• 批准号: 10301366
• 负责人: Madhu Lata S. Chauhan
• 金额: $ 8万
• 依托单位: BAYLOR COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-11-12 至 2023-10-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10301366
• 关键词: Ablation; Amniotic Fluid; Animals; Birth; Cells; Data; Estradiol; Exhibits; Fetal Growth Retardation; First Pregnancy Trimester; Gelatinase B; Genes; Growth; High Risk Woman; Human; Hypertension; Hypotensives; Impairment; Infusion procedures; Knock-out; Knockout Mice; Knowledge; MMP2 gene; Matrix Metalloproteinases; Mediating; Mediator of activation protein; Messenger RNA; Molecular; Mus; Nature; Nitric Oxide; Oxytocin; Pathologic; Peptides; Phase; Phenotype; Pilot Projects; Placenta; Placentation; Pre-Eclampsia; Pregnancy; Pregnancy Complications; Pregnancy Trimesters; Pregnancy loss; Pregnant Women; Premature Birth; Prevention; Production; Progesterone; Prostaglandins; Publishing; Rattus; Receptor Protein-Tyrosine Kinases; Reporting; Role; Second Pregnancy Trimester; Series; Serum; Signal Transduction; Spontaneous abortion; Stimulus; Supplementation; System; Testing; Vascular Endothelial Growth Factor Receptor-1; antagonist; base; blood pressure elevation; blood pressure regulation; design; endothelial dysfunction; experimental study; hypertensive; knock-down; mortality; mouse model; novel; pathophysiology of preeclampsia; pregnant; pup; receptor expression; reproductive; response; tool; trophoblast; uterine contractility

Abstract Adrenomedullin2 (ADM2) is a novel hypotensive peptide that promotes trophoblast invasion. Lower ADM2 levels are associated with pregnancy complications such as spontaneous abortion, fetal growth restriction (FGR) and preeclampsia (PE).Pilot data shows that ablation of ADM2 gene causes PE-like manifestations such as elevated blood pressure (BP) and increased serum levels of soluble fms-like tyrosine kinase-1 (sFLT- 1), along with early parturition and increased pup mortality in pregnant ADM2 knockout (ADM-/-) mice. This data strongly supports our published studies showing: 1) Higher placental and serum levels of ADM2 during the invasive phase of placental development in human pregnancy, 2) ADM2 mediated increases in the invasive capacity of 1st trimester extravillous trophoblast cells (EVCTs) in human pregnancy, 3) decreased serum and placental ADM2 levels in PE and decreased ADM2 in amniotic fluid of pregnant women in 2nd trimester who develop PE. Further, while impaired nitric oxide (NO) production and elevated synthesis and secretion of placental sFLT-1 is reported to cause endothelial dysfunction in PE, blocking ADM2 in rat pregnancy decrease placental NO/ matrix metallo-proteinase (MMP) system accompanied with FGR and impaired placental vasculature. In addition, knockdown of ADM2 in trophoblast cells decreases the expression of MMP2, MMP-9 and eNOS mRNA. Therefore, based on above mentioned reports and pilot data, our central hypothesis is that “Global ablation of ADM2 results in pregnancy complications mimicking preeclampsia in human and that, it functions through NO/MMP system “. This hypothesis will be tested using three specific aims. Specific Aim-1: Assess the effect of ADM2 ablation on feto-placental growth, circulatory levels of nitric oxide, 17β-estradiol, progesterone and blood pressure regulation during pregnancy; and identify if NO supplementation can rescue early parturition and increased pup mortality, in ADM2-/- animals, Specific Aim-2: Determine if ablation of ADM2 in mice advances uterine contractility and potentiates uterine contractile responses to stimuli such as oxytocin and prostaglandin-F2α, through increase in their receptor expression and, Specific Aim-3: Identify 1) downstream signaling mechanism involved in the invasive function of ADM2 in EVCTs and, 2) assess if ADM2 supplementation can increase the invasive capacity of EVCTs from PE, which are reported to exhibit less invasive phenotype compared to those from normal pregnancy. Since the majority of studies in humans are limited by their inherent correlative nature, our proposed approach will allow us to characterize the endogenous functions of ADM2 in pregnancy in a series of mechanistic experiments and its potential role in the pathophysiology of PE. These studies could potentially fill the gaps in the knowledge of mediators of placental functions that may hold great potential for the design and implementation of an effective prevention/treatment for pathological pregnancies in women at high risk.

摘要 肾上腺髓质素2（Adrenomedullin 2，ADM 2）是一种促进滋养细胞侵袭的新型促增殖肽。低ADM 2 水平与妊娠并发症，如自然流产，胎儿生长受限 (FGR)初步数据显示，ADM 2基因的切除导致PE样表现， 例如升高的血压（BP）和增加的可溶性fms样酪氨酸激酶-1（sFLT-1）血清水平。 沿着妊娠ADM 2敲除（ADM-/-）小鼠的早期分娩和增加的幼仔死亡率。这 数据强烈支持我们发表的研究，显示：1）在妊娠期间， 人妊娠中胎盘发育的侵袭性阶段，2）ADM 2介导的侵袭性 人妊娠早期绒毛外滋养层细胞（EVCT）的能力，3）降低血清和 妊娠中期孕妇PE中胎盘ADM 2水平和羊水中ADM 2水平降低， 发展体育。此外，虽然受损的一氧化氮（NO）的生产和增加的合成和分泌， 据报道，胎盘sFLT-1在PE中引起内皮功能障碍，阻断大鼠妊娠期ADM 2减少 胎盘NO/基质金属蛋白酶系统与FGR的关系 脉管系统此外，在滋养层细胞中敲低ADM 2可降低MMP 2、MMP-9的表达， 和eNOS mRNA。因此，基于上述报告和试点数据，我们的中心假设是， “ADM 2的全面消融导致类似人类先兆子痫的妊娠并发症， 通过国家办事处/小额供资和微型企业方案系统发挥作用“。这一假设将通过三个具体目标进行检验。具体目标1： 评估ADM 2消融对胎儿-胎盘生长、一氧化氮循环水平、17β-雌二醇、 孕激素和血压调节在怀孕期间;并确定如果没有补充可以挽救 在ADM 2-/-动物中，早期分娩和幼仔死亡率增加，具体目标-2：确定是否消融 小鼠中的ADM 2促进子宫收缩性并增强子宫对刺激物的收缩反应， 催产素和野牡丹素-F2 α，通过增加其受体表达，特异性目的-3：鉴别1） 参与EVCT中ADM 2侵袭性功能的下游信号传导机制，2）评估ADM 2 补充可以增加来自PE的EVCT的侵入能力，据报道， 与正常妊娠相比，侵袭性表型。 由于大多数人类研究受到其固有相关性的限制，我们建议 这种方法将使我们能够在一系列的研究中描述ADM 2在妊娠中的内源性功能。 机制实验及其在PE病理生理学中的潜在作用。这些研究可能会填补 胎盘功能介质知识的差距可能对设计和开发具有巨大潜力 有效预防/治疗高危妇女的病理性妊娠。