RESEARCH PROJECT 1

研究项目1

• 批准号: 7162961
• 负责人: JOSE C FERNANDEZ-CHECA
• 金额: $ 14.58万
• 依托单位: UNIVERSITY OF SOUTHERN CALIFORNIA
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7162961
• 关键词: HMG coA reductases; alcoholic liver cirrhosis; benzodiazepine receptor; biological signal transduction; cardiolipins; cholesterol; cysteine endopeptidases; ethanol; gangliosides; genetically modified animals; glutathione; laboratory mouse; laboratory rat; liver cells; liver disorder; membrane permeability; membrane transport proteins; mitochondrial membrane; molecular cloning; nuclear factor kappa beta; oxidative stress; phosphodiesterases; protein transport; sphingomyelin phosphodiesterase; tumor necrosis factor alpha

Tumor necrosis factor-a- (TNF) and mitochondrial GSH (mGSH) are two factors that modulate alcohol-induced liver injury and progression of alcoholic liver disease (ALD). The overall goal of this proprosal is to identify the signaling intermediates generated by TNF that target mitochondria and the role of mitochondrial cholesterol and lipid composition on the regulation of mGSH and mitochondrial permeability transition (MPT). Specific aims : 1. Role of acidic sphingomyelinase (ASMase) on alcohol-mediated hepatocellular injury. Ceramide functions as a lipid death effector through its interaction with mitochondria. Thus, we will examine the specific role of ASMase on the sensitization of the liver to alcohol feeding vs. known contributors of TNF cytotoxicity (Bid, cathepsin B). Rats with inactive endogenous ASMase and ASMase deficient mice will be fed ethanol chronically evaluating the sensitization of the liver to alcohol-induced liver injury. 2. Contribution of ganglioside GD3 to the progression of ALD. Ganglioside GD3 (GD3), a sialic-acid containing glycosphingolipid synthesized from ceramide within the Golgi network, interacts with mitochondria by an actin cytoskeleton vesicular trafficking. The intracellular trafficking of GD3 will be characterized in hepatocytes from alcohol-fed rats and its role in alcohol liver injury will be assessed in GD3 synthase knockout mice. 3. Regulation of mGSH by cholesterol: intramitochondrial cholesterol trafficking and role of peripheral benzodiazepine receptor (PBR). The mGSH arises by the mGSH carrier whose activity is sensitive to altered membrane fluidity due to increased cholesterol deposition. We will determine the temporal relationship between incrased mitochondrial cholesterol and mGSH depletion by alcohol feeding. In addition, we will examine the regulation of cholesterol by alcohol, the role of hydroxymethylglutaryI-CoA reductse and the collaboration of PBR in the intramitochondrial trafficking of cholesterol. 4. MPT: role of cardiolipin and MPT components. MPT is key in TNF-mediated hepatocellular injury and alcohol has been shown to potentiate MPT. Since cardiolipin, an exclusive mitochondrial phospholipid, has been recently suggested to interact with proapoptotic Bcl-2 family members that induce MPT,we will examine the role of cardiolipin vs MPT components reconstituted liposomes in MPT regulation in mitochondria and mitoplasts isolated from alcohol-fed rats.

肿瘤坏死因子-A-（TNF）和线粒体GSH（MGSH）是调节酒精诱导的肝损伤和酒精性肝病（ALD）进展的两个因素。该预言的总体目标是确定靶向线粒体的TNF产生的信号传导中间体以及线粒体胆固醇和脂质组成在MGSH和线粒体通透性过渡（MPT）调节中的作用。具体目的：1。酸性鞘磷脂酶（ASMase）在酒精介导的肝细胞损伤中的作用。神经酰胺通过与线粒体的相互作用作为脂质死亡效应子。因此，我们将研究ASMase对肝脏对酒精喂养的敏化与TNF细胞毒性的贡献者的特定作用（BID，calterpsin b）。具有无活性内源性ASMase和ASMase缺乏小鼠的大鼠将被喂食乙醇长期评估肝脏对酒精诱导的肝损伤的敏感性。 2。神经节GD3对ALD进展的贡献。神经节GD3（GD3），一种含有从高尔基网络中神经酰胺合成的糖磷脂的唾液酸酸，与Golgi网络合成，与 线粒体通过肌动蛋白细胞骨架囊泡运输。 GD3的细胞内运输将在酒精喂养大鼠的肝细胞中进行表征，其在酒精肝损伤中的作用将在GD3合酶敲除小鼠中评估。 3。通过胆固醇调节MGSH：氨基化胆固醇的胆固醇运输和周围苯二氮卓受体（PBR）的作用。 MGSH由MGSH载体产生，其活性因胆固醇沉积增加而导致的膜流动性改变。我们将通过酒精喂养来确定递增线粒体胆固醇和MGSH消耗之间的时间关系。此外，我们将检查胆固醇对胆固醇的调节，这是羟基戊二甲酰coA的作用 还原和PBR在胆固醇的Intochrial室内贩运方面的合作。 4。MPT：Cardiolipin和MPT成分的作用。 MPT是TNF介导的肝细胞损伤的关键，并且已显示酒精可增强MPT。由于Cardiolipin是一种独家的线粒体磷脂，最近有人建议与诱导MPT的促凋亡Bcl-2家族成员相互作用，我们将研究CardioLipin vs CardioLipin vs MPT成分在Mitochocoplasts和线粒体中的MPT调节中重构脂质体的作用。