LIPID ALDEHYDES AND ETHANOL-INDUCED LIVER INJURY

本项目的目的是研究慢性酒精摄入的能力 摄取以刺激肝脏产生化学反应性醛 有潜力作为酒精中间体的产品- 导致肝脏损伤。拟议的研究旨在确定 酒精诱导的小叶组织学改变与组织学改变的相关性 免疫细胞化学与生化和分子改变 带状特异性肝细胞和分离的线粒体水平。 具体来说，描述了测量浓度的实验 大鼠肝脏中的“游离”丙二醛、4-羟基壬烯醛和己醛 在长期喂食酒精之后。脂类和蛋白质络合的羰基 也将被测量以量化醛功能 肝细胞成分。这些物质的产生机制 乙醛产品将在孤立的门静脉周围和静脉周围进行检查 慢性大鼠肝细胞和线粒体的分离 摄入乙醇。乙醇和乙醛代谢的能力 刺激脂质过氧化将在地区性特异性中进行评估 肝细胞和分离的线粒体。稳态浓度 丙二醛、4-羟基壬烯醛和己醛将被定量为 肝细胞和线粒体脂质过氧化指标的研究 确定脂质过氧化程度、 谷胱甘肽浓度的变化和乙醇和乙醇的干扰 乙醛氧化。醛类脂类干扰的能力 将对线粒体乙醛氧化进行评估以测试 这些生物醛抑制醛的假说 脱氢酶催化乙醛氧化。最后一系列 有人提出用实验来评估特定蛋白质 在静脉周围或门静脉周围，肝细胞是加合物形成的目标 与脂类过氧化的反应性醛产物。这将是 用抗醛赖氨酸和半胱氨酸加合物的抗体测定 用于小叶、细胞和亚细胞的免疫细胞化学鉴定 易于形成醛加合物的蛋白质。总体而言， 拟议试验中采用的设计和统计分析将 允许识别小叶组织化学和 免疫细胞化学参数与生化和免疫反应的关系 肝细胞水平的分子变化。这样做的长期目标是 建议的研究是确定脂肪的醛类产物的作用 过氧化及其加合物在酒精性肝损伤中的作用 确定他们的测量作为早期指标的效用 肝细胞损伤。

The aim of this project is to investigate the ability of chronic ethanol ingestion to stimulate hepatic production of chemically reactive aldehydic products having the potential to function as intermediates in alcohol- induced liver damage. The proposed studies are designed to identify correlations of alcohol-induced changes in lobular histology and immunocytochemistry with biochemical and molecular alterations at the level of zonal-specific hepatocytes and isolated mitochondria. Specifically, experiments are described to measure concentrations of "free" malondialdehyde, 4-hydroxynonenal and hexanal in livers of rats following chronic ethanol feeding. Lipid- and protein-complexed carbonyls will also be measured to quantitate aldehydic functions hound to hepatocellular constituents. The mechanisms of production of these aldehydic products will be examined in isolated periportal and perivenous hepatocytes and isolated mitochondria obtained from rats chronically ingesting ethanol. The ability of ethanol and acetaldehyde metabolism to stimulate lipid peroxidation will be evaluated in zonal specific hepatocytes and isolated mitochondria. Steady-state concentrations of malondialdehyde, 4-hydroxynonenal and hexanal will be quantitated as indices of lipid peroxidation in hepatocytes and mitochondrial for determination of correlations between the magnitude of lipid peroxidation, alterations in glutathione concentrations and disruption of ethanol and acetaldehyde oxidation. The ability of aldehydic lipids to interfere with mitochondrial acetaldehyde oxidation will be evaluated in order to test the hypothesis that these biogenic aldehydes inhibit aldehyde dehydrogenase mediated oxidation of acetaldehyde. A final series of experiments are proposed to evaluate the hypothesis that specific proteins in perivenous or periportal hepatocytes are targets for adduct formation with reactive aldehydic products of lipid peroxidation. This will be determined by using antibodies against aldehydelysine and cysteine adducts for immunocytochemical identification of lobular, cellular and subcellular proteins predisposed for formation of aldehyde adducts. Collectively, the design and statistical analyses employed in the proposed experiments will allow identification of significant changes in lobular histochemistry and immunocytochemical parameters causally related to biochemical and molecular changes at the hepatocellular level. The long-term goal of this proposed research is to establish the role of aldehydic products of lipid peroxidation and their adducts in alcohol-induced liver injury and determine the utility of their measurement as an early indicator of hepatocellular liver damage.