The Impact of Circadian Misalignment on Colonic Barrier Homeostasis in Ulcerative Colitis

摘要 最近有令人信服的证据表明，炎症性肠病（IBD）的受试者，无论是克罗恩病， 疾病（CD）和溃疡性结肠炎（UC），通常有睡眠中断，睡眠中断与 疾病爆发的风险。睡眠/觉醒周期，免疫功能，新陈代谢和多种生物过程， 都是由昼夜节律编排的。大脑中的中枢生物钟与 和环境已被发现有助于各种代谢和胃肠道（GIT） 疾病然而，昼夜节律失调对IBD疾病活动性和GIT粘膜的影响和患病率， 炎症尚未建立。我们研究的长期目标是调查 IBD中昼夜节律失调导致GIT粘膜炎症和疾病进程假说。测试 基于这一假设，我们将对人类受试者进行一项前瞻性的实验室研究， 左侧轻度至中度溃疡性结肠炎未对准。我们将进行两个昼夜节律测量阶段 在严格控制的实验室条件下进行评估：1）基线，2）昼夜节律失调后 在非活动性UC患者和健康对照受试者中进行三天的模拟夜班后。测试 假设UC患者（与健康受试者对照组相比）对昼夜节律失调的弹性较低 我们将评估：我们的方案对昼夜节律的时间影响（目标1），通过以下方式： 夹带[从暗光褪黑激素发作到睡眠发作的时间]（Aim 1a）;外周昼夜节律， 柔性乙状结肠镜检查结肠组织和受试者外周血中的时钟基因表达 单核细胞（Aim 1b）;和结肠时钟基因表达和Per 2：：Luc活性，使用免疫组织化学方法， 结肠类器官体外模型（Aim 1c）。接下来，我们将检验昼夜节律失调将 增加UC患者（与对照组相比）的结肠通透性和粘膜炎症（Aim 2）， 以下：内镜评分、粪便钙卫蛋白、结肠屏障（通透性、AJC蛋白）和 全身屏障功能和炎症（目标2a）;对微生物群落产生不利影响 结构/功能（目的2b）;并使用2D结肠类器官单层通过共- 用TNF-α/INF-γ（Aim 2c）培养。这一创新提案的结果将大大提高我们的 了解昼夜节律失调可能在UC疾病活动和结肠 炎症，并确定新的昼夜调节的UC治疗靶点。

ABSTRACT Recently there has been compelling evidence that inflammatory bowel disease (IBD) subjects, both Crohn's disease (CD) and Ulcerative Colitis (UC), commonly have disrupted sleep, and disrupted sleep correlates with the risk of disease flare. Sleep/wake cycle, immune function, metabolism and multiple biological processes are all orchestrated by circadian rhythms. Circadian misalignment between the central circadian clock in the brain and environment has been found to contribute to a variety of metabolic and gastrointestinal tract (GIT) diseases. Yet, the prevalence and impact of circadian misalignment on IBD disease activity and GIT mucosal inflammation have not been established. The long-term objective of our research is to investigate the hypothesis that circadian malalignment worsens GIT mucosal inflammation and disease course in IBD. To test this hypothesis, we will conduct a prospective in lab study with human subjects on the impact of circadian misalignment in left sided mild to moderate Ulcerative Colitis. We will perform two circadian measures phase assessments under strictly controlled laboratory conditions at: 1) baseline, and after 2) circadian misalignment after three days of simulated night shifts in both inactive UC patients and healthy control subjects. To test the hypothesis that UC patients (compared to healthy subject controls) are less resilient to circadian misalignment we will assess: time impact of our protocol on circadian rhythms (Aim 1) by the following: phase angle of entrainment [time from dim light melatonin onset to sleep onset] (Aim1a); peripheral circadian rhythms by clock gene expression in colonic tissue from a flexible sigmoidoscopy and in subjects peripheral blood mononuclear cells (Aim1b); and colonic clock gene expression and Per2::Luc activity over 24 hours utilizing an in-vitro model of colonic organoids (Aim1c). Next, we will test the hypothesis that circadian misalignment will increase colonic permeability and mucosal inflammation in UC patients (vs. Controls) (Aim2) through the following: endoscopy score, stool calprotectin, colonic barrier (permeability, AJC proteins), and markers of systemic barrier function and inflammation (Aim 2a); adversely impacting microbial community structure/function (Aim 2b); and use 2D colonic organoid monolayers to explore ex-vivo barrier function by co- culturing with TNF-α/INF-γ (Aim 2c). The results of this innovative proposal will greatly increase our understanding of the important role circadian misalignment may have in UC disease activity and colonic inflammation, and identify new circadian regulated targets for treatment in UC.