Ethanol induced brain injury is decreased by inhibiting TIEG2 mediated cell death

通过抑制 TIEG2 介导的细胞死亡来减少乙醇引起的脑损伤

基本信息

批准号：
8464911
负责人：
Xiao-Ming Ou
金额：
$ 2.38万
依托单位：
UNIVERSITY OF MISSISSIPPI MED CTR
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-08-01 至 2015-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8464911
关键词：
Adult Affect Alcohol consumption Alcohol-Induced Disorders Alcohol-Induced Neurotoxicity Alcohols Antioxidants Apoptosis B-Lymphocytes Biochemical Biological Assay Brain Brain Injuries Cell Death Cell Line Cell Nucleus Cell Proliferation Cells Cessation of life Clinic DNA Data Dose Drug Delivery Systems Elements Enzymes Ethanol Ethanol toxicity Gel Generations Genes Genetic Polymorphism Genetic Transcription Genetic Variation Hippocampus (Brain)Human Hydrogen Peroxide Indium Injury Luciferases Mediating Mediator of activation protein Molecular Monoamine Oxidase B Movement Nerve Degeneration Neuroblastoma Neurons Neurotransmitters Nuclear Translocation Oxidative Stress Pathway interactions Predisposition Prefrontal Cortex Prevention Production Promoter Regions Proteins Public Health Publishing Rattus Reactive Oxygen Species Reporting Reverse Transcriptase Polymerase Chain Reaction Risk Factors Role Selegiline Signal Transduction TdT-Mediated dUTP Nick End Labeling Assay Testing Therapeutic Time Tissues Toxic effect Transcription Coactivator Transforming Growth Factor beta Transforming Growth Factors United States Up-Regulation Variant Western Blotting Work alcohol effect alcohol sensitivity biological adaptation to stress brain cell brain tissue catalase cell growth cell injury chromatin immunoprecipitation cytotoxicity dentate gyrus deprenyl drinking effective therapy entorhinal cortex enzyme activity expression vector genetic risk factor genetic variant human SOD2 protein inhibitor/antagonist innovation monoamine neuroprotection neuropsychological neurotoxicity novel novel therapeutic intervention oxidation prevent problem drinker protective effect rasagiline transcription factor translational study vector

项目摘要

DESCRIPTION (provided by applicant): It is well known that ethanol (EtOH) exposure damages brain tissue; however, the underlying mechanisms are not fully understood. Building on our recent work that the newly discovered cell death- mediator, transforming growth factor-¿-inducible early gene 2 (TIEG2) protein, is significantly increased by alcohol in human brain cells and also in adult rat brains, the objective of this innovative proposal is to further characterize the role of TIEG2 in EtOH-induced brain damage. TIEG2 is a transcription factor that inhibits cell growth, induces apoptosis, and increases the expression of monoamine oxidase B (MAO B). The enzymatic activity of MAO B generates H2O2, a major cause of reactive oxygen species (ROS) toxicity. EtOH reportedly increases the activity of MAO B, and secondarily increases the production of H2O2. Our published data show that physiologically-relevant EtOH increases the expression of the TIEG2-MAO B pathway in a neuronal cell line. Over-expression of TIEG2 enhances, whereas inhibitors of MAO B reduce EtOH-induced neuronal death. Additionally, a frequent TIEG2 gene variant (Gln62Arg, a polymorphism of TIEG2) alters the activity of TIEG2 and renders cells more sensitive to oxidative stress than the TIEG2 wild type. Therefore, we hypothesize that ethanol induces the expression of TIEG2 and its variant (the MAO B transcriptional activators). Secondly, we hypothesize that inhibitors of MAO B may provide protection against ethanol-induced brain tissue injury by reducing the TIEG2-MAO B- produced reactive oxygen species (ROS). Our Specific Aims are (1) To identify the molecular signaling components involved in ethanol-induced up-regulation of TIEG2; (2) To determine whether the TIEG2 gene variant (Gln62Arg) sensitizes cells to ethanol toxicity more than the TIEG2 wild type; (3) To determine the protective effects of MAO B inhibitors on cellular survival against ethanol-induced toxicity; and (4) To examine the protective effects of MAO B inhibitors on ethanol-induced neurotoxicity in adult rat brain tissues. The levels of TIEG2, MAO B, and cell death markers will be determined by quantitative real-time RT- PCR, Western blot and TUNEL assays, respectively. The cell proliferation rate, the production of ROS, and the neurodegeneration will also be determined. A comparison will be made among different groups: untreated controls; ethanol-treated; MAO B inhibitor-treated; and ethanol-treated accompanied with MAO B inhibitors. Our proposal will examine the potential role of a novel pathway involving TIEG2 and MAO B in EtOH- induced neurotoxicity and identifies a genetic risk factor that may confer susceptibility to ethanol-induced brain cell damage. It will also serve as the translational study for developing new antioxidant therapeutics for ethanol-induced brain tissue injury. Therefore, this proposal has the potential to greatly impact public health.

描述（由适用提供）：众所周知，乙醇（ETOH）暴露会损害脑组织；但是，尚未完全了解基本机制。在我们最近的工作的基础上，新发现的细胞死亡介质转化了生长因子 - 可诱导的早期基因2（TIEG2）蛋白质，它在人类脑细胞中和成年大鼠大脑中也显着增加，这一创新性建议的目的是进一步表征tieg2在ETOH诱发的脑损伤中的作用。 TIEG2是抑制细胞生长，诱导凋亡并增加单胺B（MAO B）表达的转录因子。 MAO B的酶活性产生H2O2，这是活性氧（ROS）毒性的主要原因。据报道，ETOH增加了MAO B的活性，次级增加了H2O2的产生。我们发表的数据表明，与物理相关的ETOH增加了神经元细胞系中tieg2-MaO B途径的表达。 TieG2的过表达增强，而MAO B的抑制剂减少了ETOH诱导的神经元死亡。此外，经常的tieg2基因变体（GLN62ARG，tieg2的多态性）改变了比2野生型对氧化物应激更敏感的tieg2和细胞的活性。因此，我们假设乙醇诱导了Tieg2及其变体的表达（MAO B转录激活剂）。其次，我们假设MAO B的抑制剂可以通过减少tieg2-MAO B产生的活性氧（ROS）来保护乙醇诱导的脑组织损伤。我们的具体目的是（1）识别参与乙醇引起的TIEG2上调的分子信号传导成分；（2）确定tieg2基因变体（GLN62ARG）是否比tieg2野生型更感受到细胞对乙醇的毒性；（3）确定MAO B抑制剂对乙醇诱导毒性的细胞存活的受保护作用；（4）检查MAO B抑制剂对乙醇诱导的成年大鼠脑组织神经毒性的受保护作用。 TIEG2，MAO B和细胞死亡标记的水平分别由定量实时RT-PCR，Western blot和Tunel分析确定。还将确定细胞增殖率，ROS的产生和神经退行性。在不同组之间将进行比较：未经处理的对照；乙醇处理； MAO B抑制剂治疗；并与MAO B抑制剂一起进行乙醇处理。我们的建议将研究涉及绑扎2和MAO B的新途径在ETOH诱导的神经毒性中的潜在作用，并鉴定出一种遗传危险因素，该遗传危险因素可能使乙醇诱导的脑细胞损伤具有易感性。它还将作为用于开发用于乙醇诱导的脑组织损伤的新抗氧化剂疗法的转化研究。因此，该提案有可能对公共卫生产生重大影响。