Intersections of matrix biology with inflammation in a new model of gout

痛风新模型中基质生物学与炎症的交叉点

• 批准号: 10579760
• 负责人: Robert A. Terkeltaub
• 金额: --
• 依托单位: VA SAN DIEGO HEALTHCARE SYSTEM
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-10-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10579760
• 关键词: Acceleration; Acute; Adult; Affect; Amyloid beta-Protein Precursor; Anti-Inflammatory Agents; Arthritis; Attenuated; Binding; Biological Assay; Biological Markers; Biology; C-terminal; CD44 gene; Cartilage; Cathepsin G; Chronic; Clinical Data; Cross-Sectional Studies; Crystal Formation; Crystallization; Custom; Deposition; Development; Disease; Disease Progression; Dryness; Elements; Extracellular Matrix; Female; Flare; G-substrate; Generations; Genetic; Genetic Transcription; Glycoproteins; Gout; Gouty Arthritis; Heritability; High Prevalence; Hip region structure; Homeostasis; Human; Hyperuricemia; Immunoassay; In Vitro; Inflammasome; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Arthritis; Inflammatory Response; Injectable; Injections; Joints; Knee joint; Laboratory Study; Lactoferrin; Length; Light; Link; Liquid substance; Lubricants; Macrophage; Mediating; Modeling; Mucins; Mus; Nature; Pain; Palpable; Pathogenesis; Pathway Analysis; Pathway interactions; Patients; Peptide Hydrolases; Phagocytes; Phenotype; Physiological; Prevention; Production; Proteolysis; Proteomics; Recombinants; Regulation; Resolution; Sampling; Serum; Severity of illness; Structure; Supplementation; Surface; Symptoms; Synovial Fluid; Synovitis; THBS1 gene; Testing; Therapeutic Agents; Thrombospondin 1; Thrombospondins; Tissues; Urate; Uric Acid; Validation; Variant; Veterans; Whole Blood; Work; Wrist; Xanthine Oxidase; arthropathies; articular cartilage; clinical phenotype; congenic; copolymer; disorder prevention; experimental study; foot; gain of function; gene product; glycosylation; in vivo; inhibitor; joint injury; lubricin; monocyte; new therapeutic target; novel; prevent; proband; receptor; response; screening; targeted treatment; therapeutic target; transcriptome; translational impact; treatment strategy

Hyperuricemia is fundamental in promoting the formation and accumulation of tissue deposits of monosodium urate crystals in gout, a high prevalence disease in Veterans. Urate crystals deposited in the joint promote acute, episodic flares of painful and incapacitating inflammatory arthritis by multiple pathways. Most importantly, urate crystals induce monocyte and macrophage NLRP3 inflammasome-mediated IL-1b release, and phagocyte influx and activation. Chronic inflammation lies beneath acute gout flares, including formation of articular tophi, which cause persistent synovitis and pannus-like erosive joint disease. However, several key aspects of gout pathogenesis remain unclear. In this light, asymptomatic hyperuricemia is over 5 times as prevalent than gout, and synovial fluid urate is enriched relative to serum urate in gout. Thus, passive filtering into the joint of excess circulating urate cannot be the only factor promoting tissue urate crystal deposition and symptomatic arthritis in gout. Furthermore, beyond high body urate burden, native factors that limit only ~15% of gout patients to develop palpable tophi in “tophaceous gout” are unclear. Better understanding factors that limit tophaceous gout, and their biomarkers, is vital due to association with erosive joint damage. To study novel gout prevention and therapy targets, we propose to test a paradigm-shifting core hypothesis for a gout regulation via intersection of inflammation with altered homeostasis of the extracellular matrix O-glycoprotein boundary lubricant lubricin. We specifically posit that the major gouty arthritis NLRP3/IL- 1b driver intersects with the homeostasis of lubricin to increase articular urate crystal deposition, inflammation, and disease progression in gout. Lubricin is an established, constitutive suppressor of experimental gouty inflammation. We observe that IL-1b induces xanthine oxidase and uric acid generation by macrophages, an effect blocked by exogenous lubricin. We find that lubricin markedly suppresses urate crystal formation in vitro. We also have characterized a remarkable “experiment of nature” in a 22 year old female female without hyperuricemia, who developed rapidly progressive crystal-proven gout, with classic and frequent acute flares, and erosive, destructive arthritis, affecting the feet, wrist, and hip. The proband had a heritable NLRP3 gain of function variant, an inflammatory profile of serum biomarkers and the whole blood transcriptome, attenuated serum levels of lubricin, and collective evidence consistent with altered lubricin homeostasis. Our model is that paucity of lubricin in “common gout”, due to heterogeneous mechanisms, enhances articular uric acid and increases the capacity of monosodium urate crystals to form in the joint. We thereby posit that articular lubricin deficiency, suppressible by injectable lubricin supplementation, promotes more severe acute and chronic gouty phenotypes in vivo. Translationally impactful studies will test our model by moving from in vitro to mouse to human studies. In doing so, we will test and compare mucin, and N- and C-terminal domain requirements for lubricin to limit urate crystal formation and macrophage xanthine oxidase activity, and to suppress selected gout pro-inflammatory mechanisms in macrophages. We will test the specific hypothesis that lubricin deficiency promotes ineffective resolution of IL-1b and urate crystal-induced acute articular inflammatory responses. Last, in a large, cross-sectional analysis of sera, we will test for relationships of more frequent gouty arthritis flares and tophaceous gout with low serum levels of lubricin, and certain entirely novel serum biomarkers of lubricin homeostasis pertinent to gout, including lubricin-degrading Cathepsin G activity, the Cathepsin G co-activator Lactoferrin, two inhibitors (Thrombospondin1 (TSP1/THBS1) and SERPINB6) of lubricin-degrading proteases, and the Cathepsin G substrate APP (Amyloid Precursor Protein). Completion of this work is projected to elucidate novel serum biomarkers to help guide gout treatment strategy and intensity, and new therapy targets to limit urate crystal deposition, acute and chronic synovitis, and joint damage in the disease.

高尿酸血症是促进肾小球疾病组织沉积形成和积累的基础。 痛风是退伍军人中的一种高患病率疾病。尿酸盐结晶沉积在关节内 通过多种途径促进疼痛和丧失行为能力的炎症性关节炎的急性发作。多数 重要的是，尿酸盐晶体诱导单核细胞和巨噬细胞NLRP3炎症小体介导的IL-1b释放， 以及吞噬细胞的流入和激活。慢性炎症存在于急性痛风发作之下，包括形成 关节痛点，可引起持续性滑膜炎和血管圈样腐蚀性关节病。然而，有几个关键 痛风的发病机制尚不清楚。从这个角度来看，无症状的高尿酸血症是 痛风的发病率高于痛风，且痛风患者的滑液尿酸相对血清尿酸丰富。因此，无源滤波 进入过多循环尿酸盐的连接处 不是促进组织尿酸盐结晶沉积的唯一因素 痛风的症状性关节炎。此外，除了身体尿酸负荷较高外，本土因素仅限制了~15% 痛风患者在“痛风性痛风”中是否会出现明显的痛风症尚不清楚。更好地了解以下因素 限制痛风及其生物标志物，是至关重要的，因为它与侵蚀性关节损害有关。 为了研究新的痛风预防和治疗靶点，我们建议测试一个范式转换的核心 痛风调节假说是通过炎症和细胞外稳态改变的交集来实现的 基质O-糖蛋白边界润滑剂润滑剂。我们特别假设主要的痛风性关节炎NLRP3/IL- 1B驱动程序与润滑剂的动态平衡相交，以增加关节尿酸盐晶体的沉积，炎症， 以及痛风的疾病进展。润滑剂是实验性痛风的公认的、结构性的抑制物。 发炎。我们观察到IL-1b诱导巨噬细胞产生黄嘌呤氧化酶和尿酸，以及 作用被外源润滑剂阻断。我们发现，在体外，润滑素显著抑制尿酸盐晶体的形成。 我们还在一名22岁的女性身上进行了一次引人注目的“自然实验”。 高尿酸血症，迅速发展为晶体证实的痛风，伴有典型的和频繁的急性红斑， 以及侵蚀性、破坏性的关节炎，影响脚、手腕和臀部。先证者的NLRP3可遗传增益为 功能变异，一种血清生物标记物和全血转录组的炎性特征，减弱 血清润滑素水平，以及与润滑素稳态改变一致的集体证据。我们的模式是 常见痛风中润滑剂的缺乏，由于不同的机制，增加了关节尿酸和 增加一钠尿酸盐晶体在关节中形成的能力。因此，我们假设关节润滑剂 缺乏，可通过注射润滑剂补充来抑制，会导致更严重的急性和慢性痛风 活体表型。翻译影响研究将通过从体外到小鼠再到小鼠来测试我们的模型 人体研究。在这样做的过程中，我们将测试和比较粘蛋白以及N-末端和C-末端的结构域要求 润滑剂能限制尿酸盐晶体的形成和巨噬细胞黄嘌呤氧化酶的活性，并能抑制选定的 巨噬细胞的痛风促炎机制。我们将测试特定的假设，即润滑素缺乏 促进IL-1b和尿酸盐晶体诱导的急性关节炎症反应的无效分解。最后的, 在对血清进行的大型横断面分析中，我们将测试痛风性关节炎发作频率更高的相关性。 和血清润滑素水平较低的痛风，以及某些全新的血清润滑素生物标志物 与痛风有关的动态平衡，包括组织蛋白酶G的润滑油降解活性，组织蛋白酶G共激活剂 乳铁蛋白，两种润滑油降解酶的抑制剂(血栓蛋白1/THBS1和SERPINB6)， 组织蛋白G底物APP(淀粉样前体蛋白)。这项工作的完成预计将 阐明有助于指导痛风治疗策略和强度的新血清生物标志物和新的治疗靶点 以限制尿酸盐结晶沉积，急慢性滑膜炎，关节损害的疾病。