Protective Effect of Hemin Preconditioning after Intracerebral Hemorrhage

氯化血红素预处理对脑出血后的保护作用

基本信息

批准号：
8346310
负责人：
RAYMOND F REGAN
金额：
$ 33.91万
依托单位：
THOMAS JEFFERSON UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2012
资助国家：
美国
起止时间：
2012-07-01 至 2016-05-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8346310
关键词：
Accounting Acute Intermittent Porphyria Adhesives Aftercare Anti-Inflammatory Agents Anti-inflammatory Antibodies Antioxidants Astrocytes Attenuated Autologous Behavioral Blood Blood - brain barrier anatomy Blood Clot Blood Vessels Blood coagulation Brain Brain Injuries Brain hemorrhage Cell Adhesion Molecules Cell Death Cell Survival Cells Cerebral hemisphere hemorrhage Clinical Clinical Trials Coagulation Process Cognitive deficits Complex Corpus striatum structure Cytolysis Deposition Development Disease Dose Edema Endothelial Cells Enzymes Erythrocytes Event Excision Functional disorder Gene Transfer Goals Harvest Hematoma Heme Hemin Hemoglobin Hemopexin Hemorrhage Home environment Hour Inflammation Inflammatory Inflammatory Infiltrate Injection of therapeutic agent Injury Intraperitoneal Injections Iron Ischemia Ischemic Stroke Knock-out Knockout Mice Laboratories Lead Lesion Life Mediating Microglia Modeling Morbidity - disease rate Mus Nature Nerve Degeneration Neuroglia Neurologic Neurons Oligodendroglia Outcome Oxygenases Peripheral Population Prevalence Process Protein Isoforms Proteins Publishing Resistance Safety Serine Protease Stimulus Stroke Survivors Testing Therapeutic Thrombin Time Tissues Toxic effect Toxin Transgenic Mice Traumatic Brain Injury Video Recording Wild Type Mouse cell injury collagenase digital effective therapy heme oxygenase-1 heme-binding protein improved interest intraperitoneal mortality novel object recognition overexpression oxidation preconditioning protective effect protein expression research study response

项目摘要

DESCRIPTION (provided by applicant): Intracerebral hemorrhage (ICH) is the primary event in 10-15% of strokes. A growing body of experimental evidence supports the hypothesis that release of hemin from the hematoma may contribute to oxidative cell injury in adjacent tissue. The heme oxygenase (HO) enzymes, which catalyze the rate-limiting step in hemin breakdown, regulate the response of CNS cells to hemin in a complex fashion. HO-1, the inducible isoform, has been associated with increased lesion volume and inflammation after experimental ICH, and worsened behavioral outcome. However, recent studies in the applicant's laboratory suggest that mice overexpressing HO-1 specifically in astrocytes are markedly less vulnerable to ICH than wild-type mice. Moreover, systemic administration of hemin, which is currently in clinical use to treat acute porphyrias, increased HO-1 expression in the mouse brain. When administered after ICH but before erythrocyte lysis, this treatment attenuated blood- brain barrier breakdown and cell injury surrounding a striatal hematoma. These results suggest that systemic hemin at clinically-tolerated doses provides a preconditioning stimulus that protects CNS cells from the hemin subsequently released in high concentrations from the hematoma. This safe, easily administered, and inexpensive compound may be a novel and highly effective treatment for ICH. The goal of this project is to define the therapeutic benefit of systemic hemin in two established ICH models. The specific aims are as follows: 1) Administer hemin to mice via daily i.p. injections for 1-3 days; 24 hours after the last injection, harvest striata and quanify HO-1 protein expression and activity. Identify cell populations that express HO-1 via immunostaining. 2) Induce ICH by stereotactic injection of autologous blood or collagenase into the striata of mice. Treat with hemin or vehicle control 1, 3, 6, or 12 hours later, followed in 24 hours by an additional dose. Quantify blood-brain barrier disruption and striatal edema at 3 days. 3) Quantify the effect of hemin on striatal cell viability and perihematomal inflammatory infiltrates 3 and 8 days after ICH. Assess focal deficits at these time points using corner, adhesive removal and elevated body swing tests, and activity deficits by digital analysis of home cage video recordings. 4) Compare the effects of hemin treatment on blood-brain barrier disruption, edema, neuronal viability, inflammation, and behavioral deficits in wild-type mice with those in HO-1 knockout mice. Determine the effect of the heme binding protein hemopexin on hemin therapy by performing additional experiments using hemopexin knockout mice. It is hoped that the results of this project will define the benefits of systemic hemin after ICH, and rapidly lead to clinical trials for a disease process that currently has few therapeutic options. PUBLIC HEALTH RELEVANCE: The information gained in this project may lead to new treatments for victims of hemorrhagic brain injuries. These include hemorrhagic stroke and traumatic brain injuries associated with bleeding into the brain. The ultimate goal is to reduce the cell injury that occurs in tissue surrounding the blood clot, and thereby improve the likelihoo of survival and return to an independent, productive life.

描述（由申请人提供）：脑内出血（ICH）是10-15％的中风的主要事件。越来越多的实验证据支持了这样的假设：从血肿中释放出Hemin可能会导致相邻组织中的氧化细胞损伤。血红素氧酶（HO）酶催化HEMIN分解中的速率限制步骤，以复杂的方式调节中枢神经系统细胞对HEMIN的反应。 HO-1是可诱导的同工型，与实验性ICH后的病变体积和炎症增加有关，并恶化了行为结果。但是，最近对申请人实验室的研究表明，在星形胶质细胞中特别表达HO-1的小鼠比野生型小鼠易受ICH的影响明显小。此外，目前正在用于治疗急性卟啉症的临床用途的系统给药增加了小鼠脑中的HO-1表达。当在ICH之后但在红细胞裂解之前给药时，这种治疗会减弱纹状体血肿周围的血液屏障分解和细胞损伤。这些结果表明，临床上耐受剂量的全身性血症提供了一种预处理刺激，可保护中枢神经系统细胞免受高浓度释放的Hemin免受血肿的释放。这种安全，容易施用且廉价的化合物可能是ICH的新型且高效的治疗方法。该项目的目的是在两个既定的ICH模型中定义全身HEMIN的治疗益处。具体目的如下：1）通过每日i.p.对小鼠施用对小鼠的治疗。注射1-3天；上次注射后24小时，收获纹状体和Quantive HO-1蛋白表达和活性。通过免疫染色识别表达HO-1的细胞群体。 2）通过立体定向注射自体血或胶原酶诱导ICH。用hemin或车辆对照1、3、6或12小时治疗，然后在24 小时增加剂量。量化3天的血脑屏障破坏和纹状体水肿。 3）量化HEMIN对ICH后3和8天的纹状体细胞活力和近日炎症性浸润的影响。使用角落，粘合剂去除和身体挥杆测试升高以及通过对家庭笼式视频记录的数字分析来评估这些时间点的焦点缺陷。 4）比较Hemin治疗对野生型小鼠的血脑屏障破坏，水肿，神经元活力，炎症和行为缺陷的影响那些在HO-1淘汰赛中。通过使用血红素敲除小鼠进行其他实验，确定血红素结合蛋白血兴蛋白对HEMIN治疗的影响。希望该项目的结果能定义ICH后全身性脱头的好处，并迅速导致目前几乎没有治疗选择的疾病过程进行临床试验。公共卫生相关性：该项目获得的信息可能会导致对出血性脑损伤受害者的新治疗方法。这些包括出血性中风和与大脑出血有关的脑部损伤。最终目标是减少血凝块周围组织中发生的细胞损伤，从而改善生存的可能性，并恢复独立的生产力。