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：患有唐氏综合症的人（DS）与多样化的口头抗衡 异常包括唾液产生不良和表现为发育不全的牙釉质缺陷（较薄） 搪瓷）和低矿化。负责这些改变的分子机制不是 已知。 DS搪瓷缺陷是发育性的，而不仅仅是继发性损失的继发性。唾液是 对整体口腔健康至关重要，保持口腔湿润并为语音提供重要的支持 和味道。它还包含有助于防止细菌攻击的溶质和酶。牙釉质和 唾液共同提供了针对细菌攻击的障碍，可以对健康和 生活质量。钙调神经素1（RCAN1）的调节剂是人类染色体21（HSA21）的基因 其中导致DS。 RCAN1是钙调神经酶（CN）Ca2+活化蛋白的喂养抑制剂 磷酸酶是各种细胞内信号级联反应的核心。 CN功能的损失已经 证明可以改变水通道水通道蛋白，并在唾液腺中破坏囊泡运输必不可少的 用于唾液蛋白分泌。该提议的目的是了解唾液腺和搪瓷 DS在分子水平上改变了形成，并定义了RCAN1/CN在此过程中的作用。在 强烈支持，我们的初步数据表明DP16小鼠[DP（16）1Yey]已建立的鼠标模型 DS在机械上弱且形态上异常的搪瓷。我们显示RCAN1表达 在矿化阶段被上调，并且在成熟细胞系中过表达RCAN1 显着改变线粒体功能并增加ROS的产生。我们的共同投资者拥有 证明RCAN1基因剂量的变化足以改变线粒体动力学和 在源自DS个体的诱导多能干细胞（IPSC）中的功能。有两个中央 拟议的研究中可检验的假设：1）RCAN1破坏DS中的搪瓷晶体形成 改变木材细胞中的线粒体功能和2）RCAN1 DS中CN信号的抑制 破坏唾液腺中的Ca2+信号传导，导致缺乏症。我们将使用DS鼠标模型 （DP16小鼠，RCAN1-KO小鼠，DP16 X RCAN1-KO小鼠）解决线粒体在 这些小鼠的成成木细胞，并将使用表达荧光标记为分泌和成熟的小鼠 阶段。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 用GFP小鼠越过它们，突出了SG中的分泌囊泡以分析钙信号，唾液 以及唾液中的蛋白质和溶质含量。拟议的研究很重要，因为它们将 两者都提高了我们对正常线粒体扰动的机制的理解 功能，例如在DS中发生的功能会影响牙齿健康成木板线粒体，并阐明 导致DS造成损失的机制。