Lipid Peroxidation in Alcoholic Liver Disease

脂质过氧化在酒精性肝病中的作用：长期目标是确定酒精性肝病(ALD)的发病机制。目的：1)探讨26S蛋白酶体抑制在实验性酒精性肝病大鼠肝细胞蛋白滞留中的作用。2)探讨20S蛋白酶体抑制在实验性酒精性肝病肝细胞氧化蛋白清除中的作用。3)在单个肝细胞水平上，通过对磷酸化-泛素-蛋白酶体途径的原位检测，确定蛋白酶体功能在ALD中是否受损。这些研究将集中于在大鼠和小鼠的肝脏上进行的组织病理学、免疫组织化学和生化测量之间的相关性，当肝脏组织学发生显著变化时，大鼠和小鼠灌胃酒精2-4个月。要测试的基本概念是，氧化应激和自由基诱导的损伤启动了肝细胞中蛋白质周转的变化，改变了肝细胞中蛋白质合成和蛋白质消除之间的平衡，最终结果是蛋白质滞留和细胞扩大。为了更好地了解CYP2E1在实验性酒精性肝病肝细胞蛋白滞留发病机制中的作用，我们将利用乙醇灌胃模型对表达不足或过度表达的小鼠进行研究。将确定导致肝脏胞浆中滞留的CYP2E1和其他蛋白质上调的机制。通过这种方式，将确定肝细胞增大的发病机制，并确定这一现象在ALD中所起的作用。

Role of Lipid Peroxidation in ALD: The long-term goal is to determine the pathogenesis of alcoholic liver disease (ALD). Specific Aims are: 1) To determine the role played by 26s proteasome peptidase inhibition in the protein retention in hepatocytes in experimental ALD in the rat and mouse. 2) To determine the role played by the 20s proteasome peptidase inhibition in the removal of oxidized proteins in hepatocytes in experimental ALD. 3) To determine at the individual liver cell level, using in situ assessment of the phosphorylation-ubiquitin- proteasome pathway, whether the proteasome function is damages in ALD. The studies will focus on correlations made between histopathology, immunohistochemistry and biochemical measurements made on the livers of rats and mouse fed ethanol intragastrically for 2-4 months when significant alterations of liver histology has developed. The basic concept to be tested is that oxidative stress and free radical induced injury initiates a change in protein turnover in the liver cell which shifts the balance between protein synthesis and protein elimination in the liver cell where the net result is protein retention and cell enlargement. Mice deficient in or over expressing CYP2E1 will be studies using the intragastric ethanol feeding model in order to better access the role of CYP2E1 in the pathogenesis of liver cell protein retention in experimental ALD. The mechanism which accounts for the up regulation of CYP2E1 and other proteins retained in the liver cytosol will be identified. In this way the pathogenesis o liver cell enlargement will be determined and the role that this phenomenon plays in ALD will be defined.