Molecular mechanisms of oral deficiencies in Down syndrome

唐氏综合症口腔缺陷的分子机制

• 批准号: 10658410
• 负责人: Rodrigo S. Lacruz
• 金额: $ 151.33万
• 依托单位: NEW YORK UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2026-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10658410
• 关键词: Address; Ameloblasts; Amylases; Area; Biogenesis; Calcineurin; Calcineurin inhibitor; Calcium Signaling; Carbachol; Cell Line; Cells; Chromosome 21; Confocal Microscopy; Crystal Formation; Data; Defect; Dental; Dental Enamel; Development; Down Syndrome; Elements; Enamel Formation; Enzyme-Linked Immunosorbent Assay; Enzymes; Feedback; Fluids and Secretions; Foundations; Gene Dosage; General Population; Generations; Genes; Gland; Glycolysis; Goals; Growth; Health; Heterozygote; Histology; Human Chromosomes; Image; Individual; Infection; Knockout Mice; Knowledge; Label; Longevity; Maturation-Stage Ameloblast; Measures; Mechanics; Mediating; Membrane Potentials; Mitochondria; Mitochondrial Matrix; Modeling; Molecular; Morphology; Mus; NADH; Oral; Oral cavity; Oral health; Osmosis; Oxygen Consumption; PPP3CA gene; Parotid Gland; Pathology; Patients; Phase; Pilocarpine; Predisposition; Process; Production; Property; Protein Secretion; Protein phosphatase; Proteins; Publishing; Quality of life; Quantitative Reverse Transcriptase PCR; Reporter; Reporting; Research; Research Personnel; Role; Saliva; Salivary Glands; Secondary to; Secretory Vesicles; Signal Transduction; Sorting; Speech; Taste Perception; Testing; Thinness; Time; Tooth structure; Trisomy; United States National Institutes of Health; Vesicle; Xerostomia; antimicrobial; calcification; deciduous tooth; dosage; experimental study; induced pluripotent stem cell; mechanical properties; mineralization; mitochondrial dysfunction; mitochondrial membrane; mouse model; nanoindentation; overexpression; permanent tooth; prevent; response; saliva secretion; skeletal; solute; trafficking; transcriptome sequencing; transcriptomic profiling; uptake; water channel

Project Summary/Abstract: Individuals with Down syndrome (DS) contend with a diversity of oral anomalies including poor saliva production and enamel defects that manifest as hypoplasia (thinner enamel) and hypomineralization. The molecular mechanisms responsible for these alterations are not known. DS enamel defects are developmental and not simply secondary to hyposalivation. Saliva is essential to overall oral health, keeping the oral cavity moist and providing important support for speech and taste. It also contains solutes and enzymes that help prevent bacterial attack. Tooth enamel and saliva together provide a barrier against bacterial attack and can have a significant impact on health and quality of life. Regulator of calcineurin 1 (RCAN1) is a gene on human chromosome 21 (Hsa21), trisomy of which causes DS. RCAN1 is a feed-back inhibitor of calcineurin (Cn) a Ca2+-activated protein phosphatase that is central to a diversity of intracellular signaling cascades. Loss of Cn function has been shown to alter the water channel aquaporin, and in salivary glands, disrupts vesicle trafficking essential for saliva protein secretion. The goal of this proposal is to understand how salivary gland and enamel formation are altered in DS on a molecular level and to define the role of RCAN1/Cn in this process. In strong support, our preliminary data show that Dp16 mice [Dp(16)1Yey] an established mouse model of DS, have mechanically weak and morphologically abnormal enamel. We show that RCAN1 expression is upregulated in the mineralization phase and that overexpressing RCAN1 in an ameloblast cell line significantly alters mitochondrial function and increases ROS generation. Our co-investigator has demonstrated that changes in RCAN1 gene dosage are sufficient to alter mitochondrial dynamics and function in induced pluripotent stem cells (iPSCs) derived from individuals with DS. There are two central testable hypotheses in the proposed studies: 1) RCAN1 disrupts enamel crystal formation in DS by altering mitochondrial function in ameloblasts and 2) RCAN1 suppression of Cn signaling in DS disrupts Ca2+ signaling in salivary glands leading to hyposalivation. We will use DS mouse models (Dp16 mice, Rcan1-KO mice, Dp16 x Rcan1-KO mice) to address the role of mitochondria in the ameloblasts of these mice and will use mice expressing fluorescently labelled secretory and maturation stage. To address the role of RCAN1 trisomy in salivary glands (SG), we will use the Dp16 mice and will cross them with GFP mice highlighting secretory vesicles in SG to analyze calcium signaling, salivation as well as protein and solute content in saliva. The proposed studies are significant because they will both advance our understanding of the mechanisms through which perturbation of normal mitochondrial function, such as occurs in DS, can impact dental health ameloblast mitochondria and will elucidate the mechanisms contributing to hyposalivation in DS.

项目摘要/摘要：唐氏综合征(DS)患者与多种口腔疾病抗争 异常包括唾液分泌不良和表现为发育不良(较薄)的釉质缺陷 牙釉质)和次矿化。导致这些变化的分子机制并不是 为人所知。DS釉质缺陷是发育性的，而不是简单地继发于牙釉质发育不良。唾液是 对整体口腔健康至关重要，保持口腔湿润，为说话提供重要支持 和品味。它还含有帮助防止细菌攻击的溶质和酶。牙釉质和 唾液共同提供了一种抵御细菌攻击的屏障，可以对健康和 生活质量。钙调神经磷酸酶1调节因子1(RCAN1)是人类21号染色体(Hsa21)上的一个三体基因 导致DS的原因。RCAN1是钙激活蛋白钙调神经磷酸酶(CN)的反馈抑制物 磷酸酶是细胞内各种信号级联反应的中心。CN功能已丧失 显示改变水通道水通道蛋白，并在唾液腺，扰乱囊泡运输必不可少的 用于唾液蛋白质分泌。这项建议的目标是了解唾液腺和釉质是如何 在分子水平上改变DS中的形成，并定义RCAN1/CN在这一过程中的作用。在……里面 大力支持，我们的初步数据显示，Dp16小鼠[DP(16)1Yey]建立了小鼠模型 DS，牙釉质机械强度弱，形态异常。我们展示了RCAN1表达式 在矿化期表达上调，在成釉细胞系中过表达RCAN1 显著改变线粒体功能，增加ROS生成。我们的合作调查员 证明RCAN1基因剂量的变化足以改变线粒体动力学和 在DS患者的诱导多能干细胞(IPSCs)中发挥作用。有两个中心 拟议研究中的可检验假说：1)RCAN1通过以下方式扰乱DS的釉质晶体形成 成釉细胞线粒体功能的改变和2)RCAN1抑制DS的CN信号 干扰唾液腺中的钙信号，导致唾液腺功能减退。我们将使用DS鼠标模型 (Dp16小鼠、RCAN1-KO小鼠、Dp16 x RCAN1-KO小鼠)研究线粒体在 这些小鼠的成釉细胞，并将使用表达荧光标记的分泌和成熟的小鼠 舞台。为了解决RCAN1三体在唾液腺(SG)中的作用，我们将使用Dp16小鼠并将 将它们与突出显示SG中分泌小泡的GFP小鼠杂交，以分析钙信号、唾液 以及唾液中的蛋白质和溶质含量。拟议的研究具有重要意义，因为它们将 两者都促进了我们对正常线粒体扰动的机制的理解 功能，如在DS中发生的，可以影响牙齿健康的成釉细胞线粒体，并将阐明 DS患者肺功能减退的机制。