High Urinary Phosphate Induces TLR4-mediated Inflammation and Cystogenesis in Polycystic Kidney Disease

高尿磷酸盐诱导多囊肾病中 TLR4 介导的炎症和囊肿发生

• 批准号: 10730615
• 负责人: Yan Zhang
• 金额: $ 46.95万
• 依托单位: MICHIGAN TECHNOLOGICAL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-15 至 2026-07-14
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10730615
• 关键词: Acceleration; Antiinflammatory Effect; Area; Attenuated; Autosomal Dominant Polycystic Kidney; Biomedical Research; CCL2 gene; CRISPR/Cas technology; Cell Line; Cells; Crystal Formation; Cyst; Data; Development; Diet; Disease; Disease Progression; Disease model; End stage renal failure; Equilibrium; Excretory function; Family; Fibrosis; Future; Genetic Diseases; Growth; Human; Immunologics; In Vitro; Inbred BALB C Mice; Incubated; Inflammation; Inflammatory; Inflammatory Response; Injections; Injury; Innate Immune Response; Interleukin-1 beta; Kidney; Kidney Diseases; Knock-out; Life; Lipids; Liquid substance; Macrophage; Mediating; Mediator; Messenger RNA; Michigan; Minerals; Modeling; Molecular; Mus; Mutation; Natural Immunity; Nephrons; Pathologic; Patients; Pattern; Phagocytosis; Pharmaceutical Preparations; Polycystic Kidney Diseases; Renal Replacement Therapy; Renal function; Research; Research Infrastructure; Resolution; Rodent Model; Role; Signal Pathway; TLR4 gene; TNF gene; Technology; Testing; Therapeutic; Therapeutic Effect; Training; Transforming Growth Factor beta; Universities; Work; cell injury; chemokine; cytokine; dietary; dietary restriction; diversity and inclusion; drug testing; experience; experimental study; functional loss; graduate student; human model; inflammatory marker; inorganic phosphate; interstitial; knockout gene; nanocrystal; novel; novel therapeutic intervention; pre-clinical; preservation; prevent; recruit; therapeutically effective; tolvaptan; undergraduate student; urinary

PROJECT SUMMARY/ABSTRACT Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disorder characterized by the presence of numerous fluid-filled cysts, interstitial inflammation, and fibrosis leading to a progressive decline in kidney function. Emerging evidence suggests that urinary phosphate (Pi) promotes cystogenesis and activates innate immune responses. In previous studies, a high Pi diet was shown to increase renal CaPi nanocrystal deposition and accelerated cyst growth in a non-orthologous rodent model of ADPKD; whereas the restriction of dietary Pi attenuated disease progression. Relentless cyst growth in ADPKD leads to the loss of functional nephrons and compensatory hyperfiltration of unaffected nephrons increases single nephron Pi excretion to preserve Pi balance. Supersaturated intratubular Pi levels can lead to the formation of CaPi nanocrystals that cause tubule damage and inflammatory responses. Recently, toll-like receptor 4 (TLR4), a key component of innate immunity, has been suggested to mediate high urinary Pi-induced NF-κB activation and tubule damage; however, the role of TLR4 as the primary mediator in high Pi-induced PKD acceleration has not been studied. Resolvins, a family of endogenous lipid derivatives, cease innate immune responses after injury through inhibiting NF-κB and reduce renal mineral crystal deposition by increasing phagocytosis of macrophages. Currently, the therapeutic effects of resolvins have not been evaluated in PKD. In preliminary studies, human ADPKD kidneys have elevated crystal deposition and higher TLR4 expression in cystic lining cells compared with normal human kidneys. Incubation of human ADPKD cells with CaPi nanocrystals increased TNF-α mRNA suggesting CaPi nanocrystals stimulate TLR4/NF-κB signaling pathway. Challenging Pkd1RC/RC mice, an orthologous ADPKD model, with a high Pi diet accelerated cyst growth and increased injury, inflammation, and fibrosis markers. We also found that short-term administration of resolvin D1 reduced the renal expression of inflammation markers including TNF-α, IL-1β, and MCP-1, in Pkd1RC/RC mice. Thus, we hypothesized that high urinary Pi leads to TLR4/NF-κB- dependent innate immune responses in ADPKD, and that inhibition of NF-κB using resolvins attenuates disease progression. The proposed experiments will determine: (1) the role of TLR4 in mediating the effect of high dietary Pi on cystogenesis, and (2) if inhibiting innate immune response using resolvins can prevent PKD progression. The PI will work closely with the Office of the Vice President for Research and in coordination with the strategies led by the Vice President for Diversity and Inclusion to develop and implement a robust recruitment plan for diverse undergraduate students. The PI has tremendous enthusiasm and successful experience in training undergraduate and graduate students. This proposal will: (1) provide more opportunities for undergraduate students at Michigan Technological University to participate in Biomedical Research, (2) lay the groundwork for the PI’s future contributions to the fields of PKD, and (3) diversify university research infrastructure by introducing innate immunity and PKD.

项目摘要/摘要 常染色体显性多囊性肾脏疾病（ADPKD）是一种遗传疾病，其特征是存在 众多充满液体的囊肿，间质性炎症和纤维化导致肾脏逐渐下降 功能。新兴证据表明，尿磷酸盐（PI）促进囊肿并激活先天性 免疫反应。在先前的研究中，显示高PI饮食可增加肾脏CAPI纳米晶体沉积 并在ADPKD的非传真啮齿动物模型中加速了囊肿生长；而饮食pi的限制 疾病进展减弱。 ADPKD中无情的囊肿生长会导致功能肾脏的丧失和 未受影响的肾脏的补偿性过滤增加了单个肾单位PI排泄以保留PI 平衡。过饱和的内部PI水平会导致形成引起小管的Capi纳米晶体 损害和炎症反应。最近，Toll样受体4（TLR4）是先天免疫组织化学的关键组成部分， 已经建议介导高尿液PI诱导的NF-κB激活和管损伤。但是，角色 在高PI诱导的PKD加速度中，TLR4作为主要介体尚未研究。 Resolvins，一个家庭 内源性脂质衍生物，通过抑制NF-κB损伤后停止先天免疫反应并减少 肾矿物质晶体沉积通过增加巨噬细胞的吞噬作用。目前，治疗作用 在PKD中尚未评估Resolvins的。在初步研究中，人类ADPKD的孩子提高了 与正常的人肾脏相比，在囊性内衬细胞中的晶体沉积和较高的TLR4表达。 将人ADPKD细胞与CAPI纳米晶体孵育增加了TNF-αmRNA，表明CAPI纳米晶体 刺激TLR4/NF-κB信号通路。挑战PKD1RC/RC小鼠，一种直系同源的ADPKD模型，具有 高PI饮食加速囊肿的生长并增加了损伤，感染和纤维化标记。我们还发现 短期施用Resolvin D1可降低包括TNF-α，包括TNF-α的肾脏表达 PKD1RC/RC小鼠中的IL-1β和MCP-1。这是我们假设高尿液PI导致TLR4/NF-κB- ADPKD中的依赖性先天免疫反应，并使用分辨率抑制NF-κB可减轻疾病 进展。提出的实验将确定：（1）TLR4在介导高饮食的作用中的作用 PI在囊肿上，（2）如果使用Resolvevins抑制先天免疫响应可以防止PKD进展。 PI将与研究副总裁办公室紧密合作，并与策略协调 由多样性和包容副总裁领导，以制定和实施强大的招聘计划 潜水员的本科生。 PI在培训方面具有极大的热情和成功的经验 本科生和研究生。该建议将：（1）为本科生提供更多机会 密歇根技术大学的学生参加生物医学研究，（2）为 PI对PKD领域的未来贡献，以及（3）通过介绍大学研究基础设施的多样化 先天免疫和PKD。