Targeting cell senescence in a novel model of spontaneous disc degeneration

在自发性椎间盘退变的新模型中靶向细胞衰老

• 批准号: 10839574
• 负责人: Makarand V Risbud
• 金额: $ 7.97万
• 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 2023-11-10
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10839574
• 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; 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; Modeling; 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; prevent; regenerative; regenerative tissue; senescence; therapeutic development; trait; transcriptome; transcriptome sequencing; transcriptomics; years lived with disability

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.

椎间盘退变是慢性颈痛和腰痛的主要危险因素， 影响全世界数百万人的普遍健康状况。有一个不完全的理解 椎间盘退变发病机制的部分原因是缺乏合适的动物模型。当前动物 与大多数人类椎间盘病例不同，模型主要使用创伤性损伤来促进退化 退化。虽然报道了一些自发性椎间盘退变的动物模型，但存在一些局限性 阻止它们的广泛使用。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。之前的研究已经调查了小鼠的近交系，包括 SM/J 和 LG/J 因为他们的再生能力。与“超级治疗者”菌株 LG/J 相比，SM/J 被发现是“较差的治疗者”。 然而，还没有研究调查这些小鼠品系的椎间盘健康状况。我们首次展示 SM/J 小鼠表现出自发性椎间盘退变的时间，捕捉了人类椎间盘的重要特征 病理。根据我们的新试验数据，我们假设这种退行性表型具有很强的遗传性 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 SM/J 小鼠椎间盘退变的细胞和遗传机制在三个目标中。在目标 1 中，我们将 检验 SM/J 小鼠椎间盘退变的特征是细胞存活受损的假设，改变 细胞表型、代谢和衰老。我们将对 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来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 SM/J 小鼠椎间盘退变发病机制的核心途径和机制。在目标 2 中，我们将 检验以下假设：从椎间盘中去除衰老细胞会减慢衰老的进展 SM/J 小鼠椎间盘退变。初步研究表明，衰老细胞在体内积累 SM/J 光盘。我们将在早期和建立阶段对离体器官培养的椎间盘和体内 SM/J 小鼠进行治疗 使用特征良好的 senolytic 药物分析椎间盘退变的阶段，并分析代谢、组织病理学 和基因变化。最后，在目标 3 中，我们将描述细胞的遗传机制 SM/J 小鼠的衰老和椎间盘退变。我们将进行全基因组关联研究（GWAS） 使用 LG/J x SM/J 高级交叉系 (AIL) 来发现小鼠基因组中有助于 椎间盘退变的差异。为此，AIL 小鼠将在 143,000 GIGAmuga 芯片上进行基因分型 来自几只小鼠的单核苷酸多态性 (SNP) 和圆盘将用于 RNA 测序分析。 这些数据将共同用于识别盘性状约 5 个基因的高分辨率数量性状基因座 (QTL) 每个支撑区间。负责这些 QTL 的基因将被鉴定。这个目标将产生候选人 可能导致 LG/J 和 SM/J 品系之间衰老和椎间盘退变变异的基因。