Cyclic AMP, Cytokine Modulation and Alcoholic Liver Disease

环磷酸腺苷、细胞因子调节和酒精性肝病

• 批准号: 8319664
• 负责人: CRAIG J. MCCLAIN
• 金额: $ 29.93万
• 依托单位: UNIVERSITY OF LOUISVILLE
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-20 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8319664
• 关键词: Acute-Phase Reaction; Adenylate Cyclase; Agonist; Alcoholic Hepatitis; Alcoholic Liver Cirrhosis; Alcoholic Liver Diseases; Alcohols; Animal Model; Animals; Anti-Inflammatory Agents; Anti-inflammatory; Antioxidants; Attenuated; Biological Models; Cause of Death; Cell Line; Cessation of life; Chronic; Cirrhosis; Clinical; Clinical Research; Consumption; Cyclic AMP; Data; Depressed mood; Development; Disease; Disease model; Endotoxins; Epigenetic Process; Ethanol; Evaluation; FDA approved; Glutathione; Goals; Human; IL8 gene; In Vitro; Inflammatory; Injury; Interleukin-10; Interleukin-18; Isoenzymes; Knockout Mice; Kupffer Cells; Lipopolysaccharides; Liver; Liver diseases; Mediating; Metabolism; Methionine; Misoprostol; Modeling; Modification; Molecular; Mus; Outcome; Oxidative Stress; PDE4B; Patients; Pharmaceutical Preparations; Pharmacologic Substance; Pharmacotherapy; Phosphodiesterase Inhibitors; Play; Process; Production; Rattus; Reporting; Research; Role; Serum; Stomach; System; Therapeutic Intervention; Tumor Necrosis Factor-alpha; Whole Blood; Work; alcohol exposure; animal data; base; bench to bedside; chemokine; cytokine; experience; feeding; hepatotoxin; inhibitor/antagonist; liver function; macrophage; monocyte; novel therapeutic intervention; peripheral blood; phosphoric diester hydrolase; protective effect; public health relevance; research study; volunteer

DESCRIPTION (provided by applicant): Alcoholic Liver Disease (ALD) remains a leading cause of liver-related deaths in the U.S., and there is still no FDA-approved therapy. Abnormal cytokine metabolism is a major feature of ALD. Elevated serum concentrations of tumor necrosis factor (TNF) and TNF-inducible proinflammatory cytokines/chemokines, such as IL-8 and IL-18 have been reported in patients with alcoholic hepatitis and/or cirrhosis, and levels correlated with markers of the acute phase response, liver function, and clinical outcome. Similarly, there are depressed levels of the critical anti-inflammatory cytokine IL-10. Studies in animal models support an etiologic role for cytokines in the liver injury of ALD. The major problem to be investigated in this proposal is the mechanism(s) for this dysregulated cytokine metabolism, and our overall goal is the development of novel therapeutic interventions. ALD is associated with an increase in oxidative stress with a concomitant decrease in cellular antioxidants, such as glutathione (GSH) and importantly, S-adenosyl-L-methionine (SAM), due to subnormal synthesis. Clinical studies have suggested that SAM has beneficial effects in many hepatic disorders including ALD, and numerous animal studies have clearly demonstrated the protective effects of SAM against a variety of hepatotoxins. Previous studies from our group evaluated the role of SAM in positively modulating endotoxin (LPS)-stimulated TNF and IL-10 production related to ALD. We showed that SAM decreased LPS stimulated TNF production and increased LPS stimulated IL-10 production, and that SAM increased cellular levels of cyclic AMP (cAMP), which is known to positively modulate cytokine production. We therefore began an evaluation of the role of cAMP in dysregulated cytokine production in ALD, which is the research focus of this current proposal. We present compelling preliminary data that cAMP is decreased in a macrophage cell line chronically cultured in alcohol, and in Kupffer cells from mice chronically fed ethanol intragastrically. Our working hypothesis is that altered phosphodiesterase 4B (PDE4B) and cAMP metabolism cause abnormal TNF and IL-10 metabolism, which play a critical role in the development and perpetuation of ALD. Specific Objectives for this proposal are to: 1. Document increased PDE4B expression/activity and decreased cAMP in peripheral blood monocytes from patients with alcoholic hepatitis (AH) and alcoholic cirrhosis, and evaluate whether in vitro incubation of monocytes with specific phosphodiesterase inhibitors corrects dysregulated cAMP and cytokine metabolism; 2. Determine whether PDE4 (and specifically, PDE4B) inhibition blocks the development of alcohol-induced liver injury in a murine intra-gastric ethanol-feeding model of chronic ALD and in a murine model of AH; 3. Evaluate potential molecular and epigenetic mechanisms whereby cAMP metabolism is altered in alcoholic liver disease; and 4. Evaluate the effects of combined consumption of a commercially- available adenyl cyclase agonist (Misoprostol - increases cAMP production) and a phosphodiesterase inhibitor (Pentoxyfilline - decreases cAMP breakdown) in normal volunteers and in patients with stable alcoholic cirrhosis. PUBLIC HEALTH RELEVANCE: Alcoholic Liver Disease (ALD) remains a leading cause of death from liver disease in the U.S. and there is still no FDA-approved therapy. Abnormal cytokine metabolism is a major feature of ALD. Elevated serum concentration levels of tumor necrosis factor (TNF) and TNF-inducible proinflammatory cytokines/chemokines, such as IL-8 and IL-18 have been reported in patients with alcoholic hepatitis and/or cirrhosis, and levels correlated with markers of the acute phase response, liver function, and clinical outcome. Similarly, there are depressed levels of the critical anti-inflammatory cytokine IL-10. Studies in animal models support an etiologic role for cytokines in the liver injury of ALD. The major problem to be investigated in this proposal is the mechanism(s) for this dysregulated cytokine metabolism, and our overall goal is the development of novel therapeutic interventions.

描述（由申请人提供）：酒精性肝病（ALD）仍然是美国肝脏相关死亡的主要原因，目前仍没有fda批准的治疗方法。细胞因子代谢异常是ALD的主要特征。据报道，酒精性肝炎和/或肝硬化患者血清中肿瘤坏死因子（TNF）和TNF诱导的促炎细胞因子/趋化因子（如IL-8和IL-18）浓度升高，其水平与急性期反应、肝功能和临床结果的标志物相关。同样，关键的抗炎细胞因子IL-10水平下降。动物模型研究支持细胞因子在ALD肝损伤中的病因学作用。在这个建议中要研究的主要问题是细胞因子代谢失调的机制，我们的总体目标是开发新的治疗干预措施。ALD与氧化应激增加有关，同时细胞抗氧化剂，如谷胱甘肽（GSH）和重要的s -腺苷- l-蛋氨酸（SAM），由于合成不正常而减少。临床研究表明，SAM对包括ALD在内的许多肝脏疾病都有有益作用，大量动物研究已经清楚地证明SAM对多种肝毒素具有保护作用。我们小组之前的研究评估了SAM在积极调节内毒素（LPS）刺激的TNF和与ALD相关的IL-10产生中的作用。我们发现，SAM降低了LPS刺激的TNF的产生，增加了LPS刺激的IL-10的产生，SAM增加了环AMP （cAMP）的细胞水平，cAMP是已知的积极调节细胞因子的产生。因此，我们开始评估cAMP在ALD中细胞因子产生失调中的作用，这是本提案的研究重点。我们提出了令人信服的初步数据，在酒精中长期培养的巨噬细胞系和长期灌胃乙醇小鼠的库普弗细胞中，cAMP降低。我们的工作假设是磷酸二酯酶4B （PDE4B）和cAMP代谢的改变导致TNF和IL-10代谢异常，这在ALD的发生和延续中起着关键作用。本建议的具体目标是：1。酒精性肝炎（AH）和酒精性肝硬化患者外周血单核细胞PDE4B表达/活性升高，cAMP降低，并评估特异性磷酸二酯酶抑制剂对单核细胞体外培养是否能纠正cAMP和细胞因子代谢失调；2. 在小鼠慢性ALD胃内乙醇喂养模型和小鼠AH模型中，确定PDE4（特别是PDE4B）抑制是否阻断酒精诱导的肝损伤的发展；3. 评估酒精性肝病中cAMP代谢改变的潜在分子和表观遗传机制；和4。评价市售腺苷环化酶激动剂（米索前列醇-增加cAMP生成）和磷酸二酯酶抑制剂（戊氧基菲林-减少cAMP分解）在正常志愿者和稳定的酒精性肝硬化患者中的联合使用效果。