CONTROL OF DRUG AND ETHANOL METABOLISM

药物和乙醇代谢的控制

• 批准号: 6669648
• 负责人: Gavin E Arteel
• 金额: $ 30.08万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 1978
• 资助国家: 美国
• 起止时间: 1978-03-01 至 2006-05-04
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6669648
• 关键词: Kupffer's cell; NAD(P)H dehydrogenase; alcoholic fatty liver; alcoholism /alcohol abuse; cytochrome P450; cytokine receptors; drug metabolism; endotoxins; estrogen receptors; estrogens; ethanol; free radicals; gender difference; gene expression; gene targeting; genetically modified animals; histopathology; laboratory mouse; liver metabolism; oxidative stress; oxidizing agents; tumor necrosis factor alpha

DESCRIPTION: (Adapted from the Investigator's Abstract) During the recent funding period, we have collected evidence supporting the hypothesis that early alcohol-induced liver injury involves activation of Kupffer cells by gut-derived endotoxin, oxidants and the toxic cytokine TNFa. Moreover, using the enteral feeding model of Tsukamoto and French, the investigators discovered that female rats, like humans, exhibit more injury than males and have higher blood endotoxin levels. This finding led to our discovery that estrogen increases Kupffer cell expression of the endotoxin receptor (CD14) and production of TNF(. Both parameters were decreased when the gut was sterilized with non-absorbable antibiotics. Moreover the investigators showed that increased sensitivity of Kupffer cells to endotoxin caused by acute ethanol is associated with an increase in CD14 expression. To date, reports on mechanisms of early alcohol-induced liver disease relied on work with inhibitors, which may not be specific. Accordingly, to fill critical gaps in our knowledge, the investigators will use knockout technology where specific receptors or proteins are genetically deleted to obtain clear information on causal events in mechanisms of early alcohol-induced liver injury. The unifying hypothesis we will test here using knockout technology is that endotoxin activates Kupffer cells to produce oxidants which increase TNFa production leading to early alcohol-induced liver injury. The investigators also proposed that gender differences could be explained by this hypothesis. Initially, in Aim 1 the PI will optimize, characterize and validate a mouse model of enteral alcohol delivery by determining pathology in wild-type mice, which are background strains for selected knockouts. In aim 2, the PI will determine if the primary source of oxidants in early alcohol-induced liver disease is the ethanol-inducible cytochrome P450 (CYP2E1) which the investigators expect will come predominantly from parenchymal cells or NADPH oxidase from Kupffer cells. The p47phox knockout mouse, which is NADPH oxidase deficient, will be compared wit h the CYP2E1 knockout to test the hypothesis that radical generation by Kupffer cells is a primary event in early alcohol-induced liver injury, using the enteral model characterized in Aim 1. Using the endotoxin receptor (CD14) knockout and the TNFa receptor 1 (TNFR1) knockout in enteral studies with alcohol, the investigators will test the hypothesis that endotoxin and TNFa are causally involved in early alcohol-induced liver injury in Aim 3. In Aim 4, estrogen receptor knockout mice will be used to determine if gender differences in liver injury due to alcohol can be explained by the involvement of estrogens. This work is timely and exciting since it will provide a new enteral feeding model in the mouse that will allow the investigators and others to investigate the roles of specific proteins and enzymes in alcohol-induced liver disease using the power of knockout technology. This will uniquely position us to provide unequivocal new information and fill critical gaps in our knowledge on mechanisms of early alcohol-induced liver injury.

描述：（改编自研究者摘要）在最近 资金期间，我们已经收集了证据支持假设，早期 酒精诱导的肝损伤涉及枯否细胞的激活， 肠源性内毒素、氧化剂和毒性细胞因子TNF α。此外，使用 研究人员发现， 雌性大鼠和人类一样，比雄性大鼠表现出更多的伤害， 血液内毒素水平这一发现使我们发现雌激素 增加内毒素受体（CD14）的枯否细胞表达， TNF的产生（.肠道消毒后，这两个参数均降低 非吸收性抗生素此外，调查人员表明， 急性乙醇引起枯否细胞对内毒素的敏感性增加， 与CD14表达的增加有关。迄今为止， 早期酒精诱导的肝病依赖于抑制剂的工作， 可能不具体。因此，为了填补我们知识中的关键空白， 研究人员将使用基因敲除技术， 基因被删除，以获得明确的信息，因果事件， 早期酒精性肝损伤的机制。统一假设我们 将在这里用基因敲除技术测试内毒素激活库普弗 细胞产生氧化剂，增加TNF α的产生，导致早期 酒精性肝损伤研究人员还提出， 差异可以用这个假设来解释。最初，在目标1中， 将优化，表征和验证肠内酒精的小鼠模型 通过确定野生型小鼠的病理学来递送，这是背景技术。 用于选择敲除的菌株。在目标2中，PI将确定主要 早期酒精性肝病的氧化剂来源是 乙醇诱导的细胞色素P450（CYP2E1），研究人员预计将 主要来自实质细胞或来自枯否细胞的NADPH氧化酶。 将比较NADPH氧化酶缺陷的p47phox敲除小鼠 用CYP2E1基因敲除来检验自由基产生的假设， 枯否细胞是早期酒精性肝损伤的主要事件， 目的1中表征的肠内模型。内毒素受体（CD14） 基因敲除和TNFa受体1（TNFR1）基因敲除的肠内研究， 酒精，研究人员将测试假设，内毒素和TNF α是 在Aim 3中与早期酒精诱导的肝损伤有因果关系。在目标4中， 雌激素受体敲除小鼠将用于确定性别差异是否 酒精引起的肝损伤可以解释为 雌激素。这项工作是及时和令人兴奋的，因为它将提供一个新的肠 这将使研究人员和其他人能够 探讨特定蛋白质和酶在酒精性肝损伤中的作用 利用基因敲除技术来治疗疾病这将使我们处于独一无二的地位 提供明确的新信息，填补我们知识中的关键空白， 早期酒精性肝损伤的机制。