Brain-gut circadian rhythm interactions in alcohol-induced gut leakiness

酒精引起的肠漏中脑肠昼夜节律的相互作用

• 批准号: 8320423
• 负责人: ALI KESHAVARZIAN
• 金额: $ 56.37万
• 依托单位: RUSH UNIVERSITY MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-09-30 至 2015-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8320423
• 关键词: Acute; Affect; Alcoholic Liver Diseases; Alcoholism; Alcohols; Apical; Behavioral; Biological; Biological Rhythm; Brain; Caco-2 Cells; Cells; Chronic; Circadian Rhythms; Clinical; Clock protein; Colitis; Communication; Complex; Darkness; Data; Development; Disease; Endotoxemia; Endotoxins; Epithelial; Epithelial Cells; Extravasation; Functional disorder; Gene Expression; Gene Proteins; Genes; Genetic; Goals; Health; Human; Hypothalamic structure; In Vitro; Inflammatory; Injury; Intestinal Mucosa; Intestines; Knowledge; Lead; Link; Liver; Mediating; Metabolic Diseases; Modeling; Molecular; Mus; Mutation; Organ; Outcome; Periodicity; Peripheral; Permeability; Phase; Physiological; Predisposition; Preventive Intervention; Proteins; Psychological Stress; Rattus; Regulation; Research; Risk; Rodent; Role; Series; Small Interfering RNA; Steatohepatitis; Stimulus; Stratification; Testing; Therapeutic Intervention; Time; Tissues; Wild Type Mouse; alcohol abuse therapy; alcohol effect; alcohol testing; chronic alcohol ingestion; circadian pacemaker; design; feeding; genetic manipulation; in vivo; knock-down; monolayer; mutant; novel; novel strategies; prevent; problem drinker; programs; protein complex; public health relevance; response; suprachiasmatic nucleus

DESCRIPTION (provided by applicant): The goal of this proposal is to test the novel hypothesis that disruption of synchrony between brain-gut circadian rhythms either directly by alcohol, or by environmental or genetic manipulations, is the "vulnerability" factor responsible for the differential susceptibility for EtOH-induced intestinal hyperpermeability that explains why only subset of alcoholics develop gut leakiness to endotoxins and steatohepatitis [ASH]. Our hypothesis is supported by: (1) Gut leakiness is a major contributor to endotoxemia and gut-derived endotoxin is required for ASH; (2) while EtOH universally disrupts intestinal epithelial monolayer permeability, gut leakiness occurs in only a subset of alcoholics, suggesting other factors might be involved-variability in gut leakiness; (3) The core circadian clock molecular machinery is within all organs including the central circadian clock in the hypothalamic suprachiasmatic nucleus (SCN), and intestinal epithelial cells. The SCN regulates and coordinates the expression and timing of multiple peripheral circadian molecular rhythms, possibly including brain-gut interactions of the so called "brain-gut axis," (BGA); (4) The BGA can regulate intestinal permeability, and pathological stimuli like physical and psychological stress can cause gut leakiness; (5) The circadian modulation of the brain gut communication could affect intestinal permeability since circadian genes regulate apical junctional complex (AJC) protein genes that are directly involved in regulation of intestinal permeability. Our recent in vivo mice data showed that disruption of circadian rhythms makes the intestine susceptible to injury. Also, our pilot data in Caco-2 intestinal monolayers show that alcohol stimulates expression of the clock genes Clock and Per2 and that siRNA knockdown of these genes prevents alcohol-induced monolayer hyperpermeability. We also show that Clock and Per2 proteins are increased in the intestines of alcohol fed rats with leaky gut. To test our hypothesis, we will take two different approaches. First (in Aim 1), we will use both environmental [constant phase shifts in the entraining LD cycle] & genetic [Clock mutant and Per1/Per2 KO mice] approaches to disrupt the overall circadian organization of mice to determine if such disruption leads to increased vulnerability for EtOH-induced gut leakage to endotoxins in alcohol-fed mice (8 wk chronic model). We predict that these circadian manipulations will elucidate the roles of circadian brain-gut synchrony and intestinal cell clock genes in regulating intestinal apical tight junctional proteins and gut permeability in response to chronic alcohol feeding. Second (in Aim 2), we will assess how EtOH-induced changes in central and peripheral clock function and gene expression impacts permeability to endotoxin (3 day acute and 8 wk chronic models). We predict that alcohol-mediated central and/or intestinal circadian desynchrony will result in increased injury to apical junctional complex (AJC) leading to gut leakiness. Demonstrating that circadian- mediated disrupted brain-gut communication is one critical contributing "susceptibility" factor for alcohol- induced endotoxemia would provide new targets for preventive and therapeutic interventions in ASH. PUBLIC HEALTH RELEVANCE: NARRATIVE Most people are aware that our bodies operate according to biological rhythms. These biological rhythms appear to regulate many aspects of our health but little is known about the cellular mechanisms involved. This study will test how alcohol affects the biological rhythms of the intestine as well as the brain and liver to see if this is one way alcohol can cause diseases such as alcoholic liver disease. Identifying how alcohol affects these biological rhythms in these organs may help us design new treatments for alcoholic liver disease and other alcohol related diseases.

描述（由申请人提供）：该提案的目的是测试新的假设，即直接通过酒精或环境或遗传操纵直接通过酒精或通过环境或遗传操纵来破坏同步的破坏是“脆弱性”因素，是导致埃托什诱发的肠胃过度渗透性的差异性的易感性的“脆弱性”因素。 [灰]。我们的假设得到：（1）肠道泄漏是导致内毒素血症的主要因素，灰烬需要肠道衍生的内毒素； （2）尽管EtoH普遍破坏了肠上皮单层的渗透性，但肠道泄漏仅发生在一部分酒精中毒中，这表明其他因素可能在肠道泄漏方面涉及变异性； （3）核心昼夜节律分子机械在下丘脑上张核（SCN）和肠上皮细胞中的所有器官中包括中央昼夜节律。 SCN调节并协调了多个外围昼夜节律节奏的表达和时机，可能包括所谓的“脑螺旋轴”的脑凝结相互作用，（BGA）； （4）BGA可以调节肠道渗透性，并且像身体和心理压力这样的病理刺激会导致肠道渗漏； （5）由于昼夜节律基因调节根尖连接络合物（AJC）蛋白基因，脑肠道通信的昼夜节律调节可能会影响肠道通透性，该基因直接参与了肠道通透性的调节。我们最近的体内小鼠数据表明，昼夜节律的破坏使肠道容易受到损伤。此外，我们在CACO-2肠单层中的试验数据表明，酒精刺激了时钟基因和PER2的表达，并且这些基因的siRNA敲低可阻止酒精诱导的单层超透明度。我们还表明，饮酒的大鼠肠道肠道肠道中的肠道中有时钟和PER2蛋白的增加。为了检验我们的假设，我们将采用两种不同的方法。首先（在AIM 1中），我们将使用环境[插入LD周期中的恒定相位移动]和遗传[时钟突变体和PER1/PER2 KO小鼠的方法来破坏小鼠的整体昼夜节律组织，以确定这种破坏是否会导致EtoH诱导的肠guut剂量增加，从而增加了对酒精含量的Mecice（8 wk chronic）中的肠内毒素渗漏的肠胃。我们预测，这些昼夜节律的操作将阐明昼夜节律脑脉冲同步和肠细胞钟基因在调节肠道顶点紧密连接蛋白方面的作用，以及响应慢性酒精喂养方面的肠道渗透性。其次（在AIM 2中），我们将评估ETOH诱导的中央时钟功能和基因表达的变化如何影响对内毒素的渗透性（3天急性和8周慢性模型）。我们预测，酒精介导的中央和/或肠昼夜节律的Denchrony将导致顶端连接络合物（AJC）的伤害增加，从而导致肠道渗漏。证明昼夜节律介导的脑脉络交流是酒精诱发的内毒素血症的“易感性”因子的一个关键，将为灰烬中的预防和治疗干预提供新的目标。 公共卫生相关性：叙事大多数人都知道我们的身体根据生物节奏运作。这些生物节奏似乎调节了我们健康的许多方面，但对所涉及的细胞机制知之甚少。这项研究将测试酒精如何影响肠以及大脑和肝脏的生物节奏，以查看这是否是酒精会导致酒精性肝病等疾病的一种方式。确定酒精如何影响这些器官中的这些生物节奏可能会帮助我们为酒精性肝病和其他与酒精有关的疾病设计新的治疗方法。