MECHANISMS OF LIVER INJURY BY HEPATITIS C AND ALCOHOL

丙型肝炎是美国最常见的慢性肝病， 估计有400万到500万人感染。该疾病的特征在于 肝脏炎症和进行性纤维化导致最终发展 肝硬化和/或肝细胞癌的发病率高达20-30%， 个体酒精的摄入大大增加了严重性和快速性 但酒精/HCV协同作用的机制尚不清楚。 新的治疗方法的发展受到了有限的限制。 现有的实验模型系统和缺乏对 涉及的致病机制。这项研究的长期目标是 表征了在细胞中表达HCV蛋白的转基因小鼠模型， 并使用该模型来确定氧化应激的作用， 线粒体功能障碍导致酒精肝毒性增加 慢性丙型肝炎具体目标是1.审查机制， HCV蛋白诱导的ROS产生刺激的后果。这些 实验将使用细胞培养表达系统来确定 HCV核心蛋白对基础和TNF诱导的ROS产生的影响， 异常ROS的来源。核心诱导的ROS变化对细胞的影响 抗氧化剂和NF-XB激活对存活率及其修饰将是 测定丙型肝炎病毒蛋白表达诱导的基因表达变化 将使用RNA酶保护测定来测量细胞系。2.确定 HCV蛋白表达对酒精性肝损伤的影响慢性 将进行正常和A-致敏小鼠的酒精喂养， 组织学和氧化损伤比较。酒精引起的肝脏基因改变 将使用DNA微阵列测量表达。3.评价抗氧化剂 的方法来修饰HCV/酒精诱导的细胞和肝损伤。 乙醇喂养的转基因动物和细胞培养系统将用于 确定改变HCV/酒精诱导的肝损伤的潜力， 抗氧化剂和抗TNF抗体。成功完成这些研究 将导致一个新的模型的发展，用于研究HCV诱导的 肝损伤，氧化应激在HCV/酒精中作用的新见解 诱导的肝损伤，并初步评估潜在的治疗 治疗这种疾病的方法。

Hepatitis C is the most common form of chronic liver disease in the U.S. with an estimated 4-5 million people infected. The disease is characterized by hepatic inflammation and progressive fibrosis leading to eventual development of cirrhosis and/or hepatocellular carcinoma in as many as 20-30% of individuals. Alcohol consumption greatly increases the severity and rapidity of disease progression but the mechanism of alcohol/HCV synergy is unknown. Development of new therapeutic approaches has been hampered by the limited experimental models systems available and a lack of understanding of the pathogenic mechanisms involved. The long-term objective of this study is to characterize a transgenic mouse model which expresses HCV proteins in the liver and to use this model to determine the role of oxidative stress and mitochondrial dysfunction in producing the increased liver toxicity of alcohol in chronic hepatitis C. The specific aims are 1. To examine the mechanisms and consequences of HCV protein-induced stimulation of ROS production. These experiments will use cell culture expression systems to determine the effects of HCV core protein on basal and TNF-induced ROS production and examine the source of abnormal ROS. The consequences of core-induced ROS changes to cell survival and its modification by antioxidants and NF-XB activation will be determined. Changes in gene expression induced by HCV protein expression in cell lines will be measured using RNase protection assays. 2. To determine the effects of HCV protein expression on ethanol-induced liver injury. Chronic alcohol feeding of normal and a-ansgenic mice will be performed and liver histology and oxidant injury compared. Alcohol induced changes in liver gene expression will be measured using DNA microarrays. 3. To evaluate antioxidant based approaches to modify HCV/alcohol-induced cell and liver injury. Ethanol-fed transgenic animals and cell culture systems will be used to determine the potential to modify HCV/alcohol -induced liver injury with antioxidants and anti-TNF antibodies. Successful completion of these studies will result in the development of a new model for the study of HCV-induced liver injury, new insight into the role of oxidative stress in HCV/alcohol induced liver injury, and a preliminary evaluation of potential therapeutic modalities for this disease.