Regulation and Function of Urocortins and their Receptors

尿皮质素及其受体的调节和功能

• 批准号: 7792347
• 负责人: Aditi Bhargava
• 金额: $ 36.71万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7792347
• 关键词: Abbreviations; Adrenal Glands; Affect; Agonist; Anxiety; Arrestins; Brain region; Cell Line; Cell membrane; Cells; Chronic; Clostridium difficile; Colitis; Colon; Confocal Microscopy; Corticotropin-Releasing Hormone; Corticotropin-Releasing Hormone Receptors; Crohn' s disease; Data; Development; Disease; Disease Outcome; Dose; Double-Stranded RNA; Down-Regulation; Dynamin; Employee Strikes; Endocytosis; Exhibits; Extravasation; Family; Feeding behaviors; Figs - dietary; Financial compensation; Gastrointestinal Motility; Gastrointestinal tract structure; Genes; Genetic; Genetic Models; Genus Cola; Glucocorticoids; Hormonal; Hypothalamic structure; Ileitis; Immune; Immune response; Immune system; Immunofluorescence Immunologic; Immunohistochemistry; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Bowel Diseases; Inflammatory disease of the intestine; Interleukin-10; Intestines; Knock-out; Knockout Mice; Ligands; Link; Liquid substance; Measures; Mediating; Mediator of activation protein; Messenger RNA; Modeling; Modification; Molecular; Moods; Mus; Neuraxis; Neurons; Neuropeptides; Neurosecretory Systems; Organ; Outcome; Pathway interactions; Patients; Peptide Receptor; Peptides; Piroxicam; Pituitary Hormones; Plasma; Play; Process; Production; Protein Isoforms; Proteins; Quality of life; RNA Interference; Recycling; Regulation; Research; Role; Scaffolding Protein; Severities; Signal Transduction; Stress; Sulfonic Acids; System; Testing; Therapeutic; Tissues; Toxin; Trinitrobenzenes; Ubiquitin; Weight Gain; arrestin 2; autonomic nerve; biological adaptation to stress; cytokine; defined contribution; desensitization; gastrointestinal; gastrointestinal function; hypothalamic-pituitary-adrenal axis; ileum; immunoreactivity; improved; innovation; life time cost; mortality; psychologic; public health relevance; receptor; receptor function; receptor recycling; response; single molecule; stressor; trafficking; urocortin; Abbreviations; Adrenal Glands; Affect; Agonist; Anxiety; Arrestins; Brain region; Cell Line; Cell membrane; Cells; Chronic; Clostridium difficile; Colitis; Colon; Confocal Microscopy; Corticotropin-Releasing Hormone; Corticotropin-Releasing Hormone Receptors; Crohn' s disease; Data; Development; Disease; Disease Outcome; Dose; Double-Stranded RNA; Down-Regulation; Dynamin; Employee Strikes; Endocytosis; Exhibits; Extravasation; Family; Feeding behaviors; Figs - dietary; Financial compensation; Gastrointestinal Motility; Gastrointestinal tract structure; Genes; Genetic; Genetic Models; Genus Cola; Glucocorticoids; Hormonal; Hypothalamic structure; Ileitis; Immune; Immune response; Immune system; Immunofluorescence Immunologic; Immunohistochemistry; Inflammation; Inflammation Mediators; Inflammatory; Inflammatory Bowel Diseases; Inflammatory disease of the intestine; Interleukin-10; Intestines; Knock-out; Knockout Mice; Ligands; Link; Liquid substance; Measures; Mediating; Mediator of activation protein; Messenger RNA; Modeling; Modification; Molecular; Moods; Mus; Neuraxis; Neurons; Neuropeptides; Neurosecretory Systems; Organ; Outcome; Pathway interactions; Patients; Peptide Receptor; Peptides; Piroxicam; Pituitary Hormones; Plasma; Play; Process; Production; Protein Isoforms; Proteins; Quality of life; RNA Interference; Recycling; Regulation; Research; Role; Scaffolding Protein; Severities; Signal Transduction; Stress; Sulfonic Acids; System; Testing; Therapeutic; Tissues; Toxin; Trinitrobenzenes; Ubiquitin; Weight Gain; arrestin 2; autonomic nerve; biological adaptation to stress; cytokine; defined contribution; desensitization; gastrointestinal; gastrointestinal function; hypothalamic-pituitary-adrenal axis; ileum; immunoreactivity; improved; innovation; life time cost; mortality; psychologic; public health relevance; receptor; receptor function; receptor recycling; response; single molecule; stressor; trafficking; urocortin

DESCRIPTION (provided by applicant): The corticotropin-releasing factor (CRF) family of neuropeptides (CRF and urocortins [Ucn] 1-3) and their receptors (CRFR1, CRFR2) are essential mediators of stress in the central nervous system. Therefore a systemic inhibition of their function is not an attractive therapeutic model. Components of this peptide/receptor family are prominently expressed within the intestine, where their local functions remain to be defined. Our preliminary data from CRFR2 heterozygous mice suggests that perturbation of the CRFR2 system renders the mice more susceptible to sudden stress and immune challenges. Our results suggest that new treatments for intestinal inflammatory diseases may require either antagonists or agonists of CRF receptors, depending upon the affected intestinal region and the type of inflammatory disease. A striking feature we observed during colitis was reciprocal changes in mRNA and protein levels of Ucn ligands and their receptors. These differential changes can alter Ucn-induced trafficking of receptors from and to the plasma membrane. However, the molecular mechanisms of this divergent trafficking to recycling or degradatory pathways remain unexplored. Thus, our hypothesis is that Ucn isoforms, differentially signaling through CRF receptors, govern intestinal inflammation at the molecular, cellular and organ levels. The aims of this proposal are to: Specific Aim 1. To define the systemic role of the Ucn/CRFR system in intestinal inflammation. We will use pharmacological and genetic approaches to define the systemic role of the Ucn/CRFR system in intestinal inflammation. We will determine if CRFR2 knockout and heterozygous mice exhibit differential sensitivity to inflammation and agonist treatment as compared with their wild type littermates. We will determine alterations in colitis severity by measuring changes in body weight gain, mortality, histological damage, and fluid leak. Specific Aim 2. To define the contributions of colon-specific Ucns and CRFRs in intestinal inflammation using RNA interference (RNAi). To determine the colon-specific role of the Ucn/CRFR system, we will establish the use RNAi to knockdown expression of Ucns and CRFR2 locally in the colon. We will determine the spatial and temporal effects of RNAi in the colon, and assess whether colon-specific knockdown of Ucns and CRFRs is sufficient to ameliorate or exacerbate colitis, using end points defined in Specific Aim 1. Specific Aim 3. To define the mechanism and function of Ucn1-induced trafficking of CRFR1. We will examine the influence of Ucn1 stimulation on the subcellular localization of CRFR1 using confocal microscopy and immunofluorescence. We will explore the ability of the adaptor/scaffolding proteins (2-arrestins and dynamin) to desensitize and resensitize CRFRs. We will assess Ucn1 regulation of CRFR1 activity by measuring Ucn1-stimulated intracellular Ca2+ mobilization. Thus, manipulation of the urocortins and their receptors provides an effective starting point for understanding their GI functions, which could contribute to the development of new treatments for inflammatory bowel disease. PUBLIC HEALTH RELEVANCE: Urocortins (Ucns) and corticotropin-releasing factor (CRF) are short proteins (peptides) that mediate the effects of psychological, physical and immunological stressors on hormonal responses, anxiety, mood, feeding behavior and gastrointestinal functions. CRF and Ucns expressed in the central nervous system control activity of autonomic nerves and thereby mediate the effects of central stressors on gastrointestinal motility and secretion. Studies have shown that people with active Crohn's disease have higher levels of one type of urocortin (Ucn1) than people without the disease. Our preliminary data from CRFR2 heterozygous mice suggests that perturbation of the CRFR2 system renders the mice more susceptible to sudden stress and immune challenges. However, the precise roles of specific components of Ucn peptide/receptor system in the initiation, development and progression of intestinal inflammation remain to be defined. This research is innovative in that it investigates the notion that local perturbation of the Ucn and its receptors influences the outcome of colonic inflammation. If successful, this study will establish how urocortins help maintain a normal immune response in the gut and whether manipulation of urocortins can help stop intestinal inflammation. Therapies that target this inflammatory pathway could improve the quality of life for patients with inflammatory bowel diseases and decrease the lifetime cost of treatment.

描述（由申请人提供）：神经肽释放的皮质激素释放因子（CRF）家族（CRF和尿素素[UCN] 1-3）及其受体（CRFR1，CRFR2）是中枢神经系统中压力的必要介体。因此，系统性抑制其功能不是一个有吸引力的治疗模型。该肽/受体家族的成分在肠内显着表达，其局部功能仍有待定义。我们来自CRFR2杂合小鼠的初步数据表明，CRFR2系统的扰动使小鼠更容易受到突然的压力和免疫挑战。我们的结果表明，根据受影响的肠道区域和炎症性疾病的类型，对肠道炎症性疾病的新治疗可能需要CRF受体的拮抗剂或激动剂。我们在结肠炎期间观察到的一个惊人特征是mRNA和UCN配体的蛋白质水平及其受体的相互变化。这些差异变化会改变UCN引起的受体从质膜和到质膜的运输。然而，这种不同的运输对回收或降解途径的分子机制仍未开发。因此，我们的假设是通过CRF受体差异信号传导的UCN同工型控制分子，细胞和器官水平下的肠炎。该提案的目的是：特定目的1。定义UCN/CRFR系统在肠道炎症中的系统作用。我们将使用药理学和遗传方法来定义UCN/CRFR系统在肠炎中的系统作用。我们将确定与野生型同窝仔相比，CRFR2敲除和杂合小鼠对炎症和激动剂治疗的敏感性是否差异。我们将通过测量体重增加，死亡率，组织学损害和液体泄漏来确定结肠炎严重程度的改变。具体目的2。使用RNA干扰（RNAI）定义结肠特异性UCN和CRFR在肠炎中的贡献。为了确定UCN/CRFR系统的结肠特异性作用，我们将建立使用RNAi来敲低UCN和CRFR2在结肠中的表达。我们将使用特定目的3中定义的终点3。定义UCN1诱导的CRFR1的ucn1 ALIS 1。我们将确定RNAi在结肠中的空间和时间影响，并评估UCN和CRFR的结肠特异性敲低足以改善或加剧结肠炎。我们将使用共聚焦显微镜和免疫荧光检查UCN1刺激对CRFR1亚细胞定位的影响。我们将探索衔接子/脚手架蛋白（2-次甲蛋白和动力蛋白）脱敏和对CRFR的脱敏的能力。我们将通过测量UCN1刺激的细胞内Ca2+动员来评估CRFR1活性的UCN1调节。因此，对尿仁素及其受体的操纵为理解其胃肠道功能提供了有效的起点，这可能有助于开发炎症性肠病的新疗法。公共卫生相关性：泌尿科糖（UCN）和皮质激素释放因子（CRF）是短蛋白（肽），可介导心理，身体和免疫压力源对荷尔蒙反应，焦虑，情绪，情绪，进食行为和胃肠道功能的影响。在中枢神经系统控制自主神经的活性中表达的CRF和UCN，从而介导了中央压力源对胃肠道运动和分泌的影响。研究表明，患有克罗恩病的人的水平比没有疾病的人高。我们来自CRFR2杂合小鼠的初步数据表明，CRFR2系统的扰动使小鼠更容易受到突然的压力和免疫挑战。然而，UCN肽/受体系统的特定成分在肠道炎症的发育和进展中的精确作用尚待定义。这项研究具有创新性，因为它研究了UCN局部扰动及其受体会影响结肠炎症结果的观念。如果成功的话，这项研究将确定泌尿诺素如何帮助维持肠道中的正常免疫反应，以及尿道质素的操纵是否可以帮助阻止肠道炎症。针对这种炎症途径的疗法可以改善炎症性肠病患者的生活质量，并降低治疗的寿命成本。