Regulation of Airway Goblet Cell Mucin Secretion

气道杯状细胞粘蛋白分泌的调节

• 批准号: 6875039
• 负责人: C. William Davis
• 金额: $ 29.13万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-02-15 至 2008-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6875039
• 关键词: actin binding protein; adenosine triphosphate; biological signal transduction; confocal scanning microscopy; diacylglycerols; exocytosis; genetically modified animals; goblet cells; granule; human tissue; laboratory mouse; mucins; postmortem; protein isoforms; protein kinase C; protein tyrosine kinase; respiratory epithelium; secretion; serine threonine protein kinase; shear stress; synaptotagmin; tissue /cell culture

DESCRIPTION: The obstructive pulmonary diseases (OPD), cystic fibrosis, chronic bronchitis, bronchiectasis, emphysema, and asthma, are inflammatory diseases with very different inflammatory cell profiles, cytokine responses, etc; mucin hypersecretion from airway surface goblet cells and submucosal mucous cells represents a singular, shared characteristic. Conceptually, mucin hypersecretion may result from inflammation-driven goblet cell meta/hyperplasia and/or elevated rates of mucin secretion. Although the best long-term treatment for OPDs will likely target the individual causes of inflammation, it is notable that acute relief to OPD patients, generally, could be achieved by selectively inhibiting mucin secretion. Possibly more important, such an inhibitor would help to open mucus-clogged airways to enable efficient, inhalation-based treatment of the underlying disease. Hence, our long-range goal is to study the molecular mechanisms by which mucin granule exocytosis in airway goblet cells is regulated, to identify molecular targets for selective drug therapies. It is well known that goblet cell mucin secretion is regulated by extracellular ATP and UTP acting through the P2Y2 receptor (P2Y2-R), and that the subsequent secretory response is mediated by the phospholipase C pathway through PKC and Ca2+. Yet, our knowledge of the signaling pathways involved in goblet cell regulation is incomplete. For instance, the effects of muscarinic agonists are highly controversial, there are no data relevant to the mechanisms and pathways underlying the regulation of basal mucin secretion from airway goblet cells, and the effects of agents signaling through receptors acting via tyrosine kinase pathways are uknown, though many of them do have metaplastic effects on the airways epithelium. At the molecular level, we know very little of the effectors regulating exocytosis beyond the identities of the intracellular messengers. Hence, we propose a broadly based approach using the primary cultures of human bronchial epithelial cells, airways epithelium from human lungs and genetically manipulated mice rendered metaplastic for goblet cells, and SPOC1 goblet cells to further delineate the intracellular molecular regulation of mucin granule exocytosis from airway goblet cells, and to extend our knowledge of the signaling pathways regulating goblet cell function into new areas involving basal mucin secretion, type I receptor and involvement, and mechanical shear effects.

描述：阻塞性肺疾病（OPD）、囊性纤维化、慢性支气管炎、支气管扩张、肺气肿和哮喘是炎症性疾病，其炎症细胞谱、细胞因子反应等差异很大；气道表面杯状细胞和粘膜下粘液细胞的粘蛋白分泌过多代表了一个单一的、共同的特征。从概念上讲，粘蛋白分泌过多可能是由炎症驱动的杯状细胞元/增生和/或粘蛋白分泌率升高引起的。尽管 OPD 的最佳长期治疗可能会针对炎症的个体原因，但值得注意的是，OPD 患者的急性缓解通常可以通过选择性抑制粘蛋白分泌来实现。可能更重要的是，这种抑制剂将有助于打开粘液堵塞的气道，从而能够对潜在疾病进行有效的、基于吸入的治疗。因此，我们的长期目标是研究调节气道杯状细胞中粘蛋白颗粒胞吐作用的分子机制，以确定选择性药物治疗的分子靶点。众所周知，杯状细胞粘蛋白分泌受细胞外ATP和UTP通过P2Y2受体(P2Y2-R)作用的调节，随后的分泌反应由磷脂酶C途径通过PKC和Ca2+介导。然而，我们对杯状细胞调节所涉及的信号通路的了解并不完整。例如，毒蕈碱激动剂的作用备受争议，没有与气道杯状细胞基础粘蛋白分泌调节的机制和途径相关的数据，并且通过酪氨酸激酶途径作用的受体发出信号的药物的作用尚不清楚，尽管其中许多确实对气道上皮有化生作用。在分子水平上，除了细胞内信使的身份之外，我们对调节胞吐作用的效应器知之甚少。因此，我们提出了一种基础广泛的方法，使用人支气管上皮细胞、人肺气道上皮和基因改造小鼠的杯状细胞和 SPOC1 杯状细胞的原代培养物，进一步描述气道粘蛋白颗粒胞吐作用的细胞内分子调节杯状细胞，并将我们对调节杯状细胞功能的信号通路的知识扩展到涉及基础粘蛋白分泌、I型受体和参与的新领域，和机械剪切效应。