Fatty Acid Ethyl Esters in Ethanol-induced Pancreatitis

脂肪酸乙酯在乙醇诱发的胰腺炎中的作用

• 批准号: 6546600
• 负责人: BHUPENDRA S KAPHALIA
• 金额: $ 26.08万
• 依托单位: UNIVERSITY OF TEXAS MED BR GALVESTON
• 依托单位国家: 美国
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-08-01 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6546600
• 关键词: acyltransferase; alcohol dehydrogenase; alcoholism /alcohol abuse; apoptosis; dosage; enzyme activity; enzyme induction /repression; enzyme inhibitors; esters; ethanol; fatty acids; laboratory mouse; pancreatitis; tissue /cell culture

DESCRIPTION (provided by applicant): Pancreatitis is a major health problem in alcoholics that causes high mortality and morbidity, and after biliary duct diseases, chronic alcohol abuse is the second major cause of chronic pancreatitis. However, the mechanism of alcohol-induced pancreatitis is poorly understood. Oxidative metabolism of ethanol catalyzed by alcohol dehydrogenase (ADH) is negligible in the pancreas, while nonoxidative metabolism of ethanol to fatty acid ethyl esters (FAEEs), catalyzed by FAEE synthase, appears to be the major mechanism of ethanol disposition in the pancreas during chronic alcohol abuse. Surprisingly, very little is known regarding the role of endogenously formed FAEEs in ethanol-induced pancreatitis. Based upon our preliminary studies showing - 14-fold increase in FAEE levels in the pancreas of hepatic ADH-deficient (ADH-) deer mice as compared to those in ADH-normal deer mice, and a dose- and time-dependent formation of FAEEs and FAEE-induced apoptosis upon ethanol exposure of ADH-deficient human hepatocellular carcinoma (HepG2) cells in culture, we hypothesize that increased formation of FAEEs is a triggering event in ethanol-induced pancreatitis, and that FAEEs and FAEE synthase can be early markers of pancreatic injury. Our preliminary studies also indicate that FAEEs are formed in rat pancreatic tumor (AR42J) cells in culture. Therefore, to investigate the toxic potential of endogenously formed FAEEs and elucidate their role in ethanol-induced pancreatic injury, we will use ADH- deer mice and AR42J cells. In Aim 1, we will determine the levels of FAEEs in the plasma and pancreas of ADH- deer mice after ethanol exposure in a dose- and time-dependent manner, and evaluate the biochemical and morphological parameters associated with pancreatic injury. We will evaluate apoptosis in the pancreas of ADH- deer mice, and in AR42J cells, after ethanol exposure (Aim 2). Inhibitors or inducers of FAEE synthase to attenuate or augment formation of FAEEs in AR42J cells, respectively, will be used to further examine the role of endogenously formed FAEEs in ethanol-induced apoptosis and toxicity (Aim 3). Achieving our Specific Aims 1-3 should establish the role of FAEEs in ethanol-induced pancreatic injury, lay the foundation for future human studies to develop these parameters as early markers for ethanol-induced pancreatic damage, and ultimately benefit us in developing new preventive/therapeutic strategies for early intervention before irreversible damage to pancreas occurs.

描述（由申请人提供）：胰腺炎是酗酒者的一个主要健康问题，导致高死亡率和发病率，并且继胆管疾病之后，长期酗酒是慢性胰腺炎的第二大原因。然而，人们对酒精诱发胰腺炎的机制知之甚少。乙醇脱氢酶 (ADH) 催化的乙醇氧化代谢在胰腺中可以忽略不计，而 FAEE 合酶催化的乙醇非氧化代谢为脂肪酸乙酯 (FAEE) 似乎是慢性胰腺炎期间胰腺中乙醇处置的主要机制。酗酒。令人惊讶的是，人们对内源性形成的 FAEE 在乙醇诱发的胰腺炎中的作用知之甚少。根据我们的初步研究显示，与 ADH 正常鹿小鼠相比，肝 ADH 缺陷 (ADH-) 鹿小鼠胰腺中的 FAEE 水平增加了 14 倍，并且 FAEE 的形成具有剂量和时间依赖性和 FAEE 在培养中 ADH 缺陷的人肝细胞癌细胞 (HepG2) 细胞暴露于乙醇后诱导细胞凋亡，我们假设 FAEE 形成的增加是FAEE 和 FAEE 合酶可以作为胰腺损伤的早期标志物。我们的初步研究还表明，FAEE 是在培养的大鼠胰腺肿瘤 (AR42J) 细胞中形成的。因此，为了研究内源形成的 FAEE 的毒性潜力并阐明它们在乙醇诱导的胰腺损伤中的作用，我们将使用 ADH-鹿小鼠和 AR42J 细胞。在目标 1 中，我们将以剂量和时间依赖的方式测定 ADH 鹿小鼠血浆和胰腺中 FAEE 的水平，并以剂量​​和时间依赖性方式评估与胰腺损伤相关的生化和形态参数。我们将评估乙醇暴露后 ADH 鹿小鼠胰腺和 AR42J 细胞的细胞凋亡（目标 2）。分别使用 FAEE 合酶抑制剂或诱导剂来减弱或增强 AR42J 细胞中 FAEE 的形成，将用于进一步检查内源形成的 FAEE 在乙醇诱导的细胞凋亡和毒性中的作用（目标 3）。实现我们的具体目标 1-3 应确定 FAEE 在乙醇引起的胰腺损伤中的作用，为未来的人类研究奠定基础，以开发这些参数作为乙醇引起的胰腺损伤的早期标志物，并最终有利于我们开发新的预防/在胰腺发生不可逆转的损伤之前进行早期干预的治疗策略。