DIABETES AND BLADDER SMOOTH MUSCLE METABOLIC DYSFUNCTION

糖尿病的一个广泛的并发症是膀胱。 功能障碍。尽管已经有许多关于这一效应的研究 实验性糖尿病对整体膀胱功能的影响，很少有研究 旨在了解老年人的代谢功能障碍 膀胱的细胞成分，即平滑的肌肉。这个 糖尿病大鼠大血管平滑肌代谢病理改变 动脉涉及细胞表型转化和脂质改变 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通量是一个主要缺陷。这个 与糖尿病相关的膀胱平滑肌代谢病理 都是未知的。本申请中提出的实验将利用 最新的多核核磁共振波谱方法研究 膀胱平滑肌代谢功能障碍的几个可能部位 来自糖尿病/高脂血症猪。由于平滑肌功能是 与平滑肌代谢密切相关，代谢功能障碍 这些研究揭示的结果将提供对这些机制的关键见解 糖尿病引起的膀胱平滑肌肌病。这个 调查人员将使用谷氨酸的1C-核磁共振同位素分析来 用膀胱内氧化代谢检测底物选择 来自正常(特异性靶点1a)和糖尿病/高脂血症的平滑肌 (特定目标1b)猪。负责任何更改的因素(S) 将在受控器官培养中确定底物选择 膀胱平滑肌(特异性靶点1c)。机制(S) 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31P-核磁共振进行检测 (具体目标1D)。在各种肌肉中碳水化合物的代谢 是结构化的(划分)，并且这种划分 从根本上改变新陈代谢调节和细胞功能。这个 研究人员将使用1H-核磁共振来测量分隔的程度 正常和正常膀胱平滑肌碳水化合物代谢的研究 糖尿病/高脂血症猪(特定目标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(1-13C-山梨醇由1-13C- 葡萄糖)，并确定强化山梨醇的代谢后果 途径流量(特定目标3)。这些实验将提供 对膀胱顺畅正常代谢的基本认识 肌肉和与之相关的病理性代谢变化 糖尿病。

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.