Matrix Metalloproteinases in Hepatic Ischemia and Reperfusion Injury

肝脏缺血和再灌注损伤中的基质金属蛋白酶

• 批准号: 8078969
• 负责人: Ana J. Coito
• 金额: $ 38.12万
• 依托单位: UNIVERSITY OF CALIFORNIA LOS ANGELES
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-07-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8078969
• 关键词: Acute; Address; Affect; Animals; Antibodies; Apoptosis; Basement membrane; Binding; Biological Preservation; Biological Process; Bone Marrow; Cells; Chronic; Clinical; Data; Development; Event; Extracellular Matrix; Failure; Free Radicals; Functional disorder; Funding; Gelatinase A; Gelatinase B; Gelatinases; Gene Transfer; Grant; Hepatic; Human; In Vitro; Incidence; Individual; Infiltration; Inflammatory; Injury; Lead; Leukocyte Trafficking; Leukocytes; Link; Liver; Liver Regeneration; Liver diseases; Matrix Metalloproteinase Inhibitor; Matrix Metalloproteinases; Mediating; Mediator of activation protein; Modeling; Mus; Natural regeneration; Obesity; Operative Surgical Procedures; Organ Donor; Outcome; Patients; Pattern; Peptide Hydrolases; Peptides; Physiological; Pilot Projects; Play; Population; Predisposition; Prevalence; Process; Property; Proteolysis; Public Health; Rattus; Regulation; Relative (related person); Reperfusion Injury; Risk; Role; Shock; Signal Transduction; Source; Staging; System; Testing; Therapeutic; Tissue Inhibitor of Metalloproteinase-1; Tissue Inhibitor of Metalloproteinases; Transplantation; Trauma; Vascular blood supply; Work; base; chemokine; cytokine; high risk; inhibitor/antagonist; insight; liver function; liver ischemia; liver transplantation; migration; mouse model; neutralizing antibody; novel therapeutics; overexpression; public health relevance; tumor

DESCRIPTION (provided by applicant): Hepatic ischemia reperfusion injury (IRI) occurs in all transplanted livers, in trauma, shock, and in elective surgery where blood supply to the liver is temporary interrupted. IRI causes up to 10% of early transplant failures and can lead to significantly higher incidence of acute and chronic rejections. Thousands of patients die every year while waiting for a donor organ. This gloomy scenario, together with the significant prevalence of obesity in the population, has led to an increased need of using suboptimal steatotic livers in transplantation at elevated risks of dysfunction based on their high susceptibility to IRI. In the previous funding period, our results demonstrated that specific matrix metalloproteinase-9 (MMP-9) inhibition profoundly ameliorates IRI in normal livers, and unveiled potential key roles for MMP-2 and TIMP-1 in liver injury. This proposal (i) explores the hepatoprotective properties of MMP-9 inhibition in marginal steatotic liver IRI and (ii) dissects the functions of MMP-2 and TIMP-1 in IR-induced damage in both normal and steatotic livers. We expect that the proposed work will provide fundamental insights on the individual functions of key MMPs/TIMPs, leading to the development of novel therapeutic manipulations that can minimize their detrimental effects while maximizing their beneficial functions in normal and in steatotic liver IRI. Well-established models of partial liver IRI in normal and in steatotic mice, and of ex vivo cold steatotic liver ischemia followed by iso-transplantation in rats will be used to address the following aims: (1) To dissect mechanisms by which Matrix Metalloproteinase-9 specific inhibition affects the IRI outcome in marginal steatotic livers. Using MMP-9-/- deficient mice and specific therapeutic manipulations against MMP-9, we will dissect whether specific MMP-9 inhibition (i) protects marginal steatotic livers from the I/R insult, (ii) disrupts leukocyte traffic and chemokine release/activation, and we will (iii) identify intracellular signaling mechanisms leading to MMP-9 expression in steatotic hepatic IRI; (2) To analyze mechanisms by which Matrix Metalloproteinase-2 activity affects the IRI outcome in normal and in steatotic livers. We will determine whether selective MMP-2 inhibition (i) affects liver function/preservation, (ii) results in altered expression of MMP-9, (iii) interferes with patterns of leukocyte migration and of cytokine/chemokine activation and, furthermore, we will (iv) identify the sources of MMP- 2 and their relative contribution in normal and steatotic liver IRI; and (3) To dissect the mechanisms by which tissue inhibitor of metalloproteinases-1 affects IRI in normal and in steatotic livers. We will assess the function of TIMP-1 in normal and in steatotic liver IRI by determining the impact of TIMP-1 deficiency on (i) liver function/preservation, (ii) liver regeneration and apoptosis, (iii) MMP activation, and on (iii) leukocyte recruitment and pro-inflammatory networks. Moreover, we will assess the function of Timp-1 overexpression as a therapeutic approach in partial liver IRI and in steatotic OLT. PUBLIC HEALTH RELEVANCE: Thousands of patients die every year while waiting for a donor organ; this serious situation has led to an increased use of suboptimal steatotic livers in transplantation. However, it is widely accepted that steatotic livers present very high risks of primary non-function, or dysfunction, based on their increased susceptibility to ischemia and reperfusion injury (IRI). We expect that our proposed work will lead to critical insights on the individual functions of key matrix metalloproteinases (MMPs), leading to the development of novel therapeutic manipulations that, by reducing the detrimental effects of MMPs while keeping their beneficial functions in hepatic IRI, will allow the successful utilization of suboptimal donors in transplantation.

描述（由申请人提供）：肝缺血再灌注损伤（IRI）发生在所有移植的肝脏、创伤、休克以及肝脏血液供应暂时中断的择期手术中。 IRI 导致高达 10% 的早期移植失败，并可导致急性和慢性排斥反应的发生率显着升高。每年有成千上万的患者在等待捐赠器官的过程中死亡。这种悲观的情况，加上人口中肥胖症的显着流行，导致在移植中使用次优脂肪变性肝脏的需求增加，由于它们对 IRI 的高度易感性，功能障碍的风险增加。在之前的资助期间，我们的结果表明，特异性基质金属蛋白酶 9 (MMP-9) 抑制可显着改善正常肝脏中的 IRI，并揭示了 MMP-2 和 TIMP-1 在肝损伤中的潜在关键作用。该提案 (i) 探索 MMP-9 抑制在边缘脂肪肝 IRI 中的保肝特性，(ii) 剖析 MMP-2 和 TIMP-1 在正常肝脏和脂肪肝中 IR 诱导损伤中的功能。我们期望所提出的工作将为关键 MMP/TIMP 的个体功能提供基本见解，从而开发出新的治疗方法，可以最大限度地减少其有害影响，同时最大限度地发挥其在正常和脂肪肝 IRI 中的有益功能。正常和脂肪变性小鼠的部分肝脏 IRI 模型以及大鼠体内冷脂肪肝缺血随后同种移植的成熟模型将用于实现以下目标：(1) 剖析基质金属蛋白酶 9 特异性抑制影响边缘脂肪变性肝脏 IRI 结果的机制。使用 MMP-9-/- 缺陷小鼠和针对 MMP-9 的特异性治疗操作，我们将剖析特异性 MMP-9 抑制是否 (i) 保护边缘脂肪肝免受 I/R 损伤，(ii) 破坏白细胞运输和趋化因子释放/激活，并且我们将 (iii) 确定导致脂肪肝中 MMP-9 表达的细胞内信号传导机制 IRI； (2) 分析基质金属蛋白酶-2 活性影响正常肝脏和脂肪变性肝脏中 IRI 结果的机制。我们将确定选择性 MMP-2 抑制是否 (i) 影响肝功能/保存，(ii) 导致 MMP-9 表达改变，(iii) 干扰白细胞迁移和细胞因子/趋化因子激活的模式，此外，我们将 (iv) 确定 MMP-2 的来源及其在正常和脂肪变性肝脏 IRI 中的相对贡献； (3) 剖析金属蛋白酶-1 组织抑制剂影响正常肝脏和脂肪变性肝脏中 IRI 的机制。我们将通过确定 TIMP-1 缺乏对 (i) 肝功能/保存、(ii) 肝再生和细胞凋亡、(iii) MMP 激活以及 (iii) 白细胞募集和促炎网络的影响来评估 TIMP-1 在正常和脂肪肝 IRI 中的功能。此外，我们将评估 Timp-1 过表达作为部分肝 IRI 和脂肪变性 OLT 治疗方法的功能。 公共卫生相关性：每年有数千名患者在等待捐赠器官时死亡；这种严重的情况导致在移植中越来越多地使用次优的脂肪变性肝脏。然而，人们普遍认为，脂肪肝由于其对缺血和再灌注损伤（IRI）的易感性增加而存在非常高的原发性无功能或功能障碍的风险。我们期望我们提出的工作将带来对关键基质金属蛋白酶（MMP）个体功能的重要见解，从而开发新的治疗方法，通过减少MMP的有害影响，同时保持其在肝脏IRI中的有益功能，将允许在移植中成功利用次优供体。