Role of Meprins in Ischemia Reperfusion induced renal injury

Meprins 在缺血再灌注引起的肾损伤中的作用

• 批准号: 8338299
• 负责人: Elimelda Moige Ongeri
• 金额: $ 10.39万
• 依托单位: NORTH CAROLINA AGRI & TECH ST UNIV
• 依托单位国家: 美国
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-09-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8338299
• 关键词: Actins; Acute Kidney Failure; Affect; Catalytic Domain; Cell Line; Cell physiology; Cells; Cellular Morphology; Cleaved cell; Complementary DNA; Complex; Confocal Microscopy; Cyclic AMP-Dependent Protein Kinases; Cytoskeletal Proteins; Cytoskeleton; Data; Development; Elements; Extracellular Matrix; Extracellular Matrix Proteins; Fibronectins; Gene Expression; Genes; Goals; Hypoxia; Immunohistochemistry; In Vitro; Injury; Integrins; Ischemia; Kidney; Kidney Failure; Knockout Mice; Laminin; Location; Mass Spectrum Analysis; Mediating; Meprin; Metalloproteases; Morbidity - disease rate; Mouse Strains; Mus; Outcome; Pathology; Pathway interactions; Play; Protein Isoforms; Proteins; Proteomics; Proximal Kidney Tubules; Recombinants; Reperfusion Injury; Reperfusion Therapy; Resources; Role; Signal Pathway; Signal Transduction; Signaling Molecule; Structure; Tail; Testing; Tight Junctions; Work; brush border membrane; cellular microvillus; in vitro Model; in vivo; inhibitor/antagonist; insight; kidney cell; mortality; occludin; prevent; renal ischemia; response; therapy development; villin

DESCRIPTION (provided by applicant): Ischemia reperfusion (IR) induced renal injury causes acute renal failure and is associated with high morbidity and mortality rates. The cellular mechanisms underlying IR renal injury are not known. Meprins, metalloproteases that are abundantly expressed in the brush border membranes (BBM) of proximal kidney tubules, have been implicated in the pathology of IR. Mice strains with lower levels of meprins develop less renal injury when subjected to IR. Meprin inhibitors and targeted disruption of the meprin gene both protect mice from IR induced renal injury. We recently demonstrated that meprins cleave actin and villin, the key components of the proximal tubule cell cytoskeleton, suggesting that the observed renal injury is in part due to degradation of cytoskeletal proteins. Meprin B also cleaves the catalytic subunit of protein kinase A (PKA), a protein that modulates many cellular signaling pathways. OS-9, a protein involved in the hypoxia response, has been shown to interact with the carboxyl-terminal tail of meprin. However, it is not known if OS-9 is a meprin substrate, and whether interaction between OS-9 and meprin plays a role in the pathology of IR induced renal injury. The broad long term goal of this project is to elucidate the cellular mechanisms responsible for IR induced kidney injury, and facilitate development of therapies to prevent IR associated renal failure. The central hypothesis is that meprins play a key role in the injuries observed in renal IR. This is in part due to cleavage of cytoskeletal proteins (such as villin and actin), proteins present in tight junction complexes, and extracellular matrix (ECM) proteins. Meprins may also play an indirect role by cleaving proteins that modulate specific signaling pathways (such as PKA and OS-9) and thus impacting expression of genes driven by these pathways. The proposed studies will use meprin knockout mice and proteomic approaches to identify meprin associated proteins that play a role in IR and elucidate underlying cellular mechanisms. The central hypothesis will be tested by pursuing the following three specific aims: (i) to identify meprin-associated proteins that play a role in IR induced renal injuy, (ii) to determine the role of meprins in cytoskeletal remodeling associated with IR induced renal injury, (iii) to determine if interactions between meprins and cell signaling molecules play a role in IR induced kidney injury. Results from the proposed studies are expected to have an important positive impact because elucidating the mechanisms underlying IR induced renal injury will facilitate development of therapies for preventing acute renal failure due to IR. PUBLIC HEALTH RELEVANCE: Ischemia-reperfusion (IR) causes kidney injury which leads to acute renal failure. The cellular mechanisms underlying IR renal injury are not known. There is increasing evidence that meprins contribute to renal injury in IR. The in vivo kidney meprin targets have not been identified. Data from the proposed studies will identify kidney meprin substrates that play a role in the pathology of IR, and provide insights into underlying cellular mechanisms. This will ultimately facilitate development of pharmacological agents for preventing kidney failure associated with IR renal injury.

描述（由申请人提供）：缺血再灌注（IR）诱导的肾损伤导致急性肾衰竭，并与高发病率和死亡率相关。IR肾损伤的细胞机制尚不清楚。Meprin是一种在近端肾小管刷状缘膜（BBM）中大量表达的金属蛋白酶，与IR的病理学有关。Meprin水平较低的小鼠品系在IR时发生较少的肾损伤。Meprin抑制剂和Meprin基因的靶向破坏均保护小鼠免受IR诱导的肾损伤。我们最近证明，meprins切割肌动蛋白和绒毛蛋白，近端小管细胞骨架的关键组成部分，这表明所观察到的肾损伤部分是由于细胞骨架蛋白的降解。Meprin B还切割蛋白激酶A（PKA）的催化亚基，PKA是一种调节许多细胞信号传导途径的蛋白质。OS-9是一种参与缺氧反应的蛋白质，已被证明与meprin的羧基末端尾部相互作用。然而，尚不清楚OS-9是否是meprin底物，以及OS-9和meprin之间的相互作用是否在IR诱导的肾损伤的病理学中起作用。该项目的广泛长期目标是阐明IR诱导的肾损伤的细胞机制，并促进预防IR相关肾衰竭的治疗方法的开发。核心假设是，meprins在肾IR中观察到的损伤中起关键作用。这部分是由于细胞骨架蛋白（如绒毛蛋白和肌动蛋白）、紧密连接复合物中存在的蛋白质和细胞外基质（ECM）蛋白的裂解。Meprins也可能通过切割调节特定信号传导途径（如PKA和OS-9）的蛋白质，从而影响这些途径驱动的基因表达而发挥间接作用。拟议的研究将使用meprin基因敲除小鼠和蛋白质组学方法，以确定meprin相关蛋白，在IR中发挥作用，并阐明潜在的细胞机制。将通过追求以下三个具体目标来检验中心假设：（i）鉴定在IR诱导的肾损伤中起作用的meprins相关蛋白，（ii）确定meprins在与IR诱导的肾损伤相关的细胞骨架重塑中的作用，（iii）确定meprins和细胞信号分子之间的相互作用是否在IR诱导的肾损伤中起作用，（iv）确定meprins和细胞信号分子之间的相互作用是否在IR诱导的肾损伤中起作用。 对IR所致肾损伤的保护作用。预期拟定研究的结果将产生重要的积极影响，因为阐明IR诱导的肾损伤的潜在机制将有助于开发预防IR所致急性肾衰竭的治疗方法。 公共卫生相关性：缺血再灌注（IR）引起肾损伤，进而导致急性肾衰竭。IR肾损伤的细胞机制尚不清楚。有越来越多的证据表明，meprin有助于IR肾损伤。在体内肾脏meprin的目标尚未确定。从拟议的研究数据将确定肾meprin基板中发挥作用的IR的病理，并提供深入了解潜在的细胞机制。这将最终促进用于预防与IR肾损伤相关的肾衰竭的药理学试剂的开发。