Acute Ethanol-Induced Innate Immune Response in Liver

描述（由申请人提供）：内毒素参与早期酒精性肝损伤已得到证实；支持这一假设，发病机制涉及先天免疫和炎症介质的各个方面。许多报告清楚地表明，库普弗细胞在乙醇引起的发病机制中起关键作用。具体来说，研究表明内毒素受体CD14（主要在库普弗细胞上表达）缺乏的小鼠对慢性酒精诱导的肝损伤具有抗性。这些数据表明，CD14信号可能是酒精相关肝损伤的关键成分。总的假设是，来自肠道的脂多糖激活了库普弗细胞，导致氧化剂的产生和随后的tnf - α释放增加。这一假设得到了大量使用基因治疗、基因敲除和转基因动物以及小鼠灌胃乙醇模型的研究的有力支持。尽管有大量关于内毒素在乙醇性肝损伤中的作用的新信息，但在我们的理解中仍然存在关键的空白。例如，LPS诱导的氧化剂产生的信号机制，CD14和相关信号成分在发病机制中的调节，以及决定损伤中性别相关差异的分子机制仍然未知。本应用程序的目的是解决以下基本假设：PI3激酶介导lps诱导的Kupffer细胞NADPH氧化酶生成超氧化物。2. 氧化敏感转录因子NF-kappaB和AP-1调节急性乙醇给药后CD14的表达。3. 调节先天免疫反应和转录因子激活的性别差异是女性对乙醇诱导的发病机制易感性增加的关键。下面的目标将使用基因传递技术和敲除小鼠技术来解决与LPS、PI3激酶激活和CD14表达在急性和慢性乙醇毒性中的作用相关的关键问题。

DESCRIPTION (provided by applicant): The involvement of endotoxin in early alcohol-induced liver injury is well established; supporting the hypothesis, that pathogenesis involves aspects of innate immunity and inflammatory mediators. A number of reports have clearly demonstrated that Kupffer cells play a critical role in the pathogenesis due to ethanol. Specifically, it was shown that mice deficient in the endotoxin receptor CD14, which is primarily expressed on Kupffer cells, were resistant to chronic alcohol-induced liver injury. These data suggest that CD14 signaling may be a critical component in alcohol-related liver injury. The overall hypothesis is that LPS from the gut activates Kupffer cells causing an increase in oxidant production and subsequent TNF-alpha release. This hypothesis is strongly supported by a number of studies using gene therapy, knockout and transgenic animals, as well as an in vivo mouse intragastric ethanol-feeding model. Despite a great amount of new information regarding the role of endotoxin in ethanol-induced liver injury, critical gaps still exist in our understanding. For example, the signaling mechanisms involved in LPS- induced oxidant production, the regulation of CD14 and related signaling components in pathogenesis, and the molecular mechanisms determining gender- related differences in injury remain unknown. The purpose of this application is to address the following underlying hypotheses: 1. PI3 kinase mediates LPS-induced NADPH oxidase generation of superoxide in Kupffer cells. 2. Oxidant-sensitive transcription factors NF-kappaB and AP-1 regulate CD14 expression following acute ethanol administration. 3. Gender differences in regulation of innate immune response and transcription factor activation are key to increased susceptibility to ethanol-induced pathogenesis in females. The aims below will use gene delivery techniques and knockout mouse technology to address these critical questions related to roles of LPS, PI3 kinase activation, and CD14 expression in both acute ethanol and chronic ethanol toxicity.