Epigenetic Mechanisms of Spontaneous Disc Degeneration in SM/J Mice

SM/J 小鼠椎间盘自发退变的表观遗传机制

• 批准号: 10757531
• 负责人: Makarand V Risbud
• 金额: $ 1.99万
• 依托单位: THOMAS JEFFERSON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2026-05-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10757531
• 关键词: Acute; Address; Affect; American; Animal Model; Back; Biological; Candidate Disease Gene; Canis familiaris; Cell Aging; Cell Survival; Cell physiology; Cells; ChIP-seq; Chronic; Dasatinib; Data; Disease; Epigenetic Process; Etiology; Excision; Exhibits; Gene Expression; Genes; Genetic; Genetic Variation; Genotype; Gerbils; Goals; Health; Health Status; Human; Inbred Strains Mice; Inflammatory; Injury; Intervention; Intervertebral disc structure; LG/J Mouse; Link; Low Back Pain; Measures; Metabolic; Metabolism; Modification; Molecular; Mouse Strains; Mus; Mutation; Neck; Neck Pain; Opioid; Organ Culture Techniques; Pathogenesis; Pathology; Pathway interactions; Persons; Pharmaceutical Preparations; Phenotype; Pilot Projects; Population; Prevalence; Process; Publishing; Quantitative Trait Loci; Quercetin; Reporting; Resolution; Risk Factors; SM/J Mouse; SNP array; Sand Rats; Structure; Testing; Time; Tissue Preservation; Tissues; Traumatic injury; Variant; Vertebral column; burden of illness; early onset; experience; genetic manipulation; genome wide association study; in vivo; insight; insurance claims; intervertebral disk degeneration; metabolic profile; metabolomics; mouse genome; mouse model; novel; nucleus pulposus; opioid abuse; opioid mortality; parent grant; prevent; regenerative; regenerative tissue; senescence; therapeutic development; trait; transcriptome; transcriptome sequencing; transcriptomics; years lived with disability

Parent Grant Abstract Intervertebral disc degeneration is the major risk factor associated with chronic neck and low back pain; ubiquitous health conditions that affects millions of people world-wide. There is an incomplete understanding of the pathogenesis of disc degeneration partially due to lack of an appropriate animal model. Current animal models primarily use traumatic insults to promote degeneration differing from most human cases of disc degeneration. While, a few animal models of spontaneous disc degeneration are reported, several limitations prevent their wide-spread use. Thus, there is a great need for small animal models that are more representative of human disc pathology. Previous studies have investigated inbred strains of mice including SM/J and LG/J for their regenerative ability. In contrast to LG/J, a “super healer” strain, SM/J was found to be a “poor healer”. However, there no studies have investigated the disc health status in these strains of mice. We show for the first time that SM/J mice exhibit spontaneous disc degeneration that captures important features of human disc pathology. Based on our novel pilot data, we hypothesize that this degenerative phenotype has a strong genetic basis and driven by early changes in cell phenotype, metabolism, and senescence. We will investigate the cellular and genetic mechanisms that underlie disc degeneration in SM/J mice in three Aims. In Aim 1 we will test the hypothesis that disc degeneration in SM/J mice is characterized by compromised cell survival, altered cell phenotype, metabolism, and senescence. We will perform RNA-Seq and ChIP-Seq analysis of NP tissue of SM/J and LG/J mice. We will also perform metabolomics to determine metabolic status of cells. These studies will provide unbiased insights into temporal alterations in transcriptome and metabolism to delineate pathways and mechanisms central to the pathogenesis of disc degeneration in SM/J mice. In Aim 2 we will test the hypothesis that removal of senescent cells from the intervertebral disc slows down the progression of disc degeneration in SM/J mice. Pilot studies have shown that there is an accumulation of senescent cells in SM/J discs. We will treat ex vivo organ cultured discs and SM/J mice in vivo during early and established stages of disc degeneration with well-characterized senolytic drugs and analyze metabolic, histopathological, and genetic changes. Lastly in Aim 3 we will delineate the genetic mechanisms that contribute to cell senescence and disc degeneration in SM/J mice. We will perform a genome-wide association study (GWAS) using LG/J x SM/J Advanced Intercross Lines (AILs) to discover regions of the mouse genome contributing to differences in disc degeneration. For this purpose, AIL mice will be genotyped at 143,000 GIGAmuga chip single nucleotide polymorphisms (SNPs) and discs from several mice will be used for RNA-Seq analysis. Together, these data will be used to identify high-resolution quantitative trait loci (QTL) for disc traits ~5 genes per support interval. The genes responsible for these QTL will be identified. This aim will generate candidate genes likely contributing to variation in the senescence and disc degeneration between LG/J and SM/J strains.

家长补助金摘要 椎间盘退变是与慢性颈腰痛相关的主要危险因素; 影响全世界数百万人的普遍存在的健康状况。对以下问题的理解不全面： 椎间盘退变的发病机制部分是由于缺乏合适的动物模型。当前动物 模型主要使用创伤性损伤来促进与大多数人类椎间盘病例不同的退化 退化虽然，一些动物模型的自发性椎间盘退变的报道，一些局限性， 防止其广泛使用。因此，非常需要更具代表性的小动物模型 人类椎间盘病理学以前的研究已经调查了近交系小鼠，包括SM/J和LG/J， 他们的再生能力。与LG/J相比，SM/J是一个“超级治疗者”菌株，被发现是一个“差的治疗者”。 然而，没有研究调查这些品系小鼠的椎间盘健康状况。我们第一次出现 SM/J小鼠表现出自发性椎间盘退变的时间，其捕获了人类椎间盘的重要特征 病理基于我们新的试点数据，我们假设这种退行性表型具有很强的遗传易感性。 基础，并由细胞表型、代谢和衰老的早期变化驱动。我们将调查 细胞和遗传机制的基础上的椎间盘退变的SM/J小鼠在三个目的。在目标1中， 检验SM/J小鼠椎间盘退变的特征在于细胞存活受损、改变 细胞表型、代谢和衰老。我们将对NP-RNA的NP组织进行RNA-Seq和ChIP-Seq分析。 SM/J和LG/J小鼠。我们还将进行代谢组学，以确定细胞的代谢状态。这些研究 将为转录组和代谢的时间变化提供公正的见解，以描绘途径 以及SM/J小鼠椎间盘退变发病机制的核心。在目标2中，我们将测试 从椎间盘中去除衰老细胞减缓椎间盘进展的假设 SM/J小鼠的退化。初步研究表明，在SM/J中存在衰老细胞的积累， 光盘。我们将在体外器官培养的椎间盘和SM/J小鼠的早期和建立阶段进行体内治疗。 椎间盘退行性变与良好的特点senolytic药物和分析代谢，组织病理学，和遗传 变化最后，在目标3中，我们将描述导致细胞衰老和椎间盘突出的遗传机制。 SM/J小鼠的退化。我们将使用LG/J x SM/J进行全基因组关联研究（GWAS）。 先进的互交系（AIL），以发现小鼠基因组中导致椎间盘差异的区域 退化为此，将在143，000 GIGAmuga芯片单核苷酸水平对AIL小鼠进行基因分型。 来自几只小鼠的基因多态性（SNP）和圆盘将用于RNA-Seq分析。这些数据一起 将用于鉴定圆盘性状的高分辨率数量性状基因座（QTL）~每个支持区间5个基因。 将鉴定负责这些QTL的基因。这一目标将产生候选基因可能有助于 LG/J和SM/J两个品系在衰老和椎间盘退变方面的差异。