DIABETES AND BLADDER SMOOTH MUSCLE METABOLIC DYSFUNCTION

糖尿病与膀胱平滑肌代谢功能障碍

• 批准号: 2906343
• 负责人: Christopher D Hardin
• 金额: $ 10.34万
• 依托单位: UNIVERSITY OF MISSOURI-COLUMBIA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-30 至 2001-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2906343
• 关键词: Krebs' cycle; animal tissue; carbohydrate metabolism; diabetes mellitus; enzyme activity; enzyme inhibitors; glucose metabolism; glucose transport; glycogenesis; hyperlipidemia; medical complication; metabolism disorder; muscle metabolism; nuclear magnetic resonance spectroscopy; organ culture; oxidation; phosphorylation; protein kinase; pyruvate dehydrogenase; smooth muscle; sorbitol; urinary bladder disorder; vascular smooth muscle

One widespread complication of diabetes mellitus is urinary bladder dysfunction. Although there have been numerous studies on the effects of experimental diabetes on overall bladder function, few studies have been aimed at understanding the metabolic dysfunction of the major cellular component of urinary bladder which is smooth muscle. The metabolic pathologies associated with diabetes in smooth muscle of large arteries involve cell phenotypic transformation and alterations in lipid and glucose metabolism. However, in microvascular smooth muscle, pathological flux through the sorbitol pathway is a primary defect. The metabolic pathologies associated with diabetes in bladder smooth muscle are unknown. The experiments proposed in this application will utilize state-of-the-art multinuclear NMR spectroscopic methods to investigate several possible sites of metabolic dysfunction in bladder smooth muscle from diabetic/hyperlipidemic pigs. Since smooth muscle function is closely linked to smooth muscle metabolism, metabolic dysfunctions unveiled by these studies will provide key insights into the mechanisms of diabetes-induced myopathies of bladder smooth muscle. The investigators will use 1 C-NMR isotopomer analysis of glutamate to examine the substrate selection by oxidative metabolism in bladder smooth muscle from normal (specific aim 1a) and diabetic/hyperlipidemic (specific aim 1b) pigs. The factor(s) responsible for any alterations in substrate selection will be identified in controlled organ culture of bladder smooth muscle (specific aim 1c). The mechanism(s) for the alteration in substrate selection (inhibition of pyruvate dehydrogenase or glucose transport/phosphorylation) will be examined using 31P-NMR (specific aim 1d). In various smooth muscles carbohydrate metabolism is structured (compartmentalized) and this compartmentalization fundamentally alters metabolic regulation and cell function. The investigators will use 1H-NMR to measure the extent of compartmentation of carbohydrate metabolism in bladder smooth muscle from normal and diabetic/hyperlipidemic pigs (specific aim 2). To determine whether bladder smooth muscle exhibits metabolic pathology similar to microvascular smooth muscle, the investigators will measure sorbitol pathway activity (1-13C-sorbitol production specifically from 1-13C- glucose) and determine the metabolic consequences of enhanced sorbitol pathway flux (specific aim 3). These experiments will provide fundamental insights to the normal metabolism of the bladder smooth muscle and to the pathological metabolic changes associated with diabetes.

糖尿病的一个普遍并发症是膀胱 功能障碍 尽管有很多研究表明 实验性糖尿病对整体膀胱功能的影响，很少有研究 旨在了解主要人群的代谢功能障碍 膀胱的细胞组成部分，即平滑肌。 的 与糖尿病相关的大血管平滑肌代谢病理学 动脉涉及细胞表型转化和脂质 和葡萄糖代谢。 然而，在微血管平滑肌中， 通过山梨醇途径的病理性流量是主要缺陷。 的 膀胱平滑肌中与糖尿病相关的代谢病理 是未知的。 本申请中提出的实验将利用 最先进的多核NMR光谱方法来研究 膀胱平滑肌代谢功能障碍的几个可能部位 来自糖尿病/高血糖猪。 由于平滑肌功能 与平滑肌代谢密切相关，代谢功能障碍 这些研究揭示的信息将为我们提供关于 糖尿病引起的膀胱平滑肌肌病。 的 研究人员将使用谷氨酸的1C-NMR同位素分析， 通过膀胱中的氧化代谢检查底物选择 来自正常（特定目的1a）和糖尿病/高血脂平滑肌 （具体目标1b）猪。 造成任何变更的因素 将在受控器官培养中鉴定底物选择 膀胱平滑肌（具体目标1c）。 机制的作用 底物选择的改变（丙酮酸脱氢酶的抑制 或葡萄糖转运/磷酸化）将使用31 P-NMR进行检查 （具体目标1d）。 在各种平滑肌中碳水化合物代谢 是结构化的（划分），这种划分 从根本上改变了代谢调节和细胞功能。 的 研究人员将使用1H-NMR来测量区室化的程度 膀胱平滑肌中碳水化合物代谢的正常和 糖尿病/高血糖猪（具体目标2）。 以确定是否 膀胱平滑肌表现出类似于 微血管平滑肌，研究人员将测量山梨醇 途径活性（1- 13 C-山梨醇生产，特别是从1- 13 C- 葡萄糖），并确定增强山梨糖醇的代谢后果 途径通量（具体目标3）。这些实验将提供 基本见解的正常代谢的膀胱顺利 肌肉和病理代谢变化相关的 糖尿病