ETHANOL EFFECTS ON PROTEOLYTIC SYSTEMS IN THE LIVER

乙醇对肝脏蛋白水解系统的影响

• 批准号: 6629576
• 负责人: Terrence M. Donohue
• 金额: $ 18.6万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-08-01 至 2005-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6629576
• 关键词: adduct; alcoholic beverage consumption; aldehydes; biotransformation; enzyme activity; enzyme structure; ethanol; immunoprecipitation; laboratory rat; liver cells; liver metabolism; lysosomes; nuclear factor kappa beta; oxidation; proteasome; protein degradation; protein metabolism; protein protein interaction; proteolysis; ubiquitin

This application is for compeptitive renewal of ongoing research into the mechanisms by which alcohol consumption affects proteolytic pathways in liver cells. It's major hypothesis is that the degradation of abberant proteins is a crucial event in cell survival and that ethanol-mediated alterations of the protein degradative pathways in liver cells can significantly affect the destruction of proteins modified by the products of ethanol oxidation. In Specific Aim 1, we will measure the catabolism of native, aldehyde-modified and oxidized lysozyme in intact hepatocytes from control and ethanol-fed rats in order to determine whether ethanol administration alters the degradation rate of this exogenously-added modified protein. In Specific Aim 2 we will examine the nature of the ethanol-induced decline in the activity of the multicatalytic proteinase (proteasome) by examining whether ethanol causes changes in subunit composition, associations with accessory proteins, or the formation of aldehyde adducts on the immunoprecipitated enzyme. In addition, the proteasome will be purified from livers of control and ethanol-fed rats to ascertain whether such alterations in enzyme activity are stable, thereby providing some indication of the nature of ethanol-induced alterations. In Specific Aim 3 we will determine whether ubiquitylation and or ubiquitin-mediated proteolysis of protein substrates is/are affected by protein modification due to ethanol-derived metabolic products. This aim will utilize a heterologous in vitro proteolytic system to analyze the formation and the degradation of ubiquitin-protein conjugates. We will also conduct experiments with primary hepatocytes to determine whether aldehyde adduct formation can inhibit the destruction of specific modified proteins, including the regulatory protein, I-kappa B-alpha.

该应用是为了恢复对饮酒影响肝细胞中蛋白水解途径的机制的康复性研究。 它的主要假设是，多种蛋白质的降解是细胞存活中的一个关键事件，并且乙醇介导的肝细胞中蛋白质降解途径的改变可以显着影响通过乙醇氧化产物修饰的蛋白质破坏。 在特定的目标1中，我们将测量来自对照和乙醇喂养大鼠完整的肝细胞中天然，醛改性和氧化溶菌酶的分解代谢，以确定乙醇给药是否会改变这种外源性化改良的蛋白质的降解速率。 在特定目标2中，我们将通过检查乙醇的活性下降的性质，通过检查乙醇是否导致亚基组成的变化，与辅助蛋白的相关性或在免疫原子蛋白蛋白酶上的醛加合物的形成。 此外，蛋白酶体将从对照和乙醇喂养大鼠的肝脏中纯化，以确定酶活性的这种改变是否稳定，从而提供了乙醇诱导的改变的性质。 在特定的目标3中，我们将确定蛋白质底物的泛素化和/或泛素介导的蛋白水解是否受到乙醇衍生的代谢产物的蛋白质修饰的影响。 该目标将利用异源体外蛋白水解系统来分析泛素 - 蛋白质结合物的形成和降解。 我们还将对原代肝细胞进行实验，以确定醛加合物的形成是否可以抑制特定修饰蛋白的破坏，包括调节蛋白I-kappa B-alpha。

项目成果

Intracellular proteolytic systems in alcohol-induced tissue injury.

酒精引起的组织损伤中的细胞内蛋白水解系统。

• 发表时间: 2003
• 期刊: Alcohol research & health : the journal of the National Institute on Alcohol Abuse and Alcoholism
• 作者: DonohueJr,TerrenceM;Osna,NataliaA
• 通讯作者: Osna,NataliaA

Effect of acute and chronic alcohol treatment and their superimposition on lysosomal, cytoplasmic, and proteosomal protease activities in rat skeletal muscle in vivo.

急性和慢性酒精治疗及其叠加对大鼠骨骼肌体内溶酶体、细胞质和蛋白体蛋白酶活性的影响。

• DOI: 10.1053/meta.2002.28967
• 发表时间: 2002
• 期刊: Metabolism: clinical and experimental
• 作者: Koll,M;Ahmed,S;Mantle,D;Donohue,TM;Palmer,TN;Simanowski,UA;Seltz,HK;Peters,TJ;Preedy,VR
• 通讯作者: Preedy,VR