Beta-cell Metabolism and Insulin Secretion

β细胞代谢和胰岛素分泌

• 批准号: 6341402
• 负责人: JONATHAN V ROCHELEAU
• 金额: $ 3.48万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-09-01 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/6341402
• 关键词: Krebs' cycle; NAD(H) phosphate; acid base balance; confocal scanning microscopy; fluorescence microscopy; glucose metabolism; hormone regulation /control mechanism; insulin; insulin sensitivity /resistance; intracellular transport; juvenile animal; laboratory mouse; mitochondria; pancreatic islet function; pancreatic islets; pyruvates; radioimmunoassay; tissue /cell culture

Islets of Langerhans are pancreatic micro-organs that play a central role in blood glucose homeostasis by secreting insulin, glucagon, and other hormones in a regulated manner. The overall goal of this research is to quantitatively determine the biochemical dynamics involved in glucose- stimulated insulin secretion from intact pancreatic islets. More specifically,, this study will address the role that cytoplasmic pH has on pyruvate transport into mitochondria, and will also address the role that cytoplasmic pH has on pyruvate transport into mitochondria, and will also address the role of mitochondria NADPH-shuttles in the insulin secretion process. In these studies, two-photon microscopy will be used to non-invasively monitor cellular NAD(P)H levels, with the ability to spatially separate signals from the cytoplasm and mitochondria. Metabolism will be correlated with beta-cell function by monitoring insulin secretion using established techniques such as radioimmuno assays and amperometry, or using fluorescence methods if feasible. Established fluorescence methodologies will be used to assay the cytoplasmic pH during nutrient stimulation. All studies will be mirrored in the NS-1 cell line, a classic cell culture model for beta-cells, which will allow a specific validations of this heavily used cell culture model.

朗格汉斯岛是胰腺微器官，通过以调节的方式分泌胰岛素、胰高血糖素和其他激素，在血糖稳态中发挥核心作用。这项研究的总体目标是定量确定完整胰岛葡萄糖刺激胰岛素分泌所涉及的生化动力学。更具体地说，本研究将探讨细胞质 p​​H 对丙酮酸转运至线粒体的作用，还将探讨细胞质 p​​H 对丙酮酸转运至线粒体的作用，还将探讨线粒体 NADPH 穿梭在胰岛素中的作用分泌过程。在这些研究中，双光子显微镜将用于非侵入性监测细胞 NAD(P)H 水平，能够在空间上分离来自细胞质和线粒体的信号。通过使用放射免疫测定和电流分析等现有技术或在可行的情况下使用荧光方法监测胰岛素分泌，将代谢与β细胞功能相关联。已建立的荧光方法将用于测定营养刺激期间细胞质的 pH 值。所有研究都将反映在 NS-1 细胞系中，NS-1 细胞系是 β 细胞的经典细胞培养模型，这将允许对这种广泛使用的细胞培养模型进行特定验证。