MODULATION OF MONOCARBOXYLIC ACID TRANSPORTERS IN BRAIN

描述：乳酸盐和相关的一元羧酸很重要 大脑新陈代谢的底物和代谢产物。在条件下 如饥饿、高脂肪消耗和早期发育(新生儿或 哺乳新生儿)、乳酸盐、丙酮酸和酮等单羧酸盐 身体可以从血液中提取出来，并被大脑用作燃料。 最近的证据表明，星形胶质细胞和 神经元利用星形胶质细胞产生的乳酸 神经激活。这项提议的总体目标是 脑内单羧酸转运体的特征及其在脑内的作用 血脑运输和脑代谢。这包括分子 负责转运的膜蛋白的鉴定 一元羧酸(乳酸、丙酮酸、乙酸乙酯和^D-羟基丁酸 酸)穿过内皮细胞、星形胶质细胞和 神经元.其细胞位置、表达 调节，以及在大脑代谢中的作用。主要的假设是 测试的是：1)所需的单羧酸转运体(MCT) 大鼠脑内星形胶质细胞和神经元之间存在代谢偶联 皮质、海马体和小脑；2)至少两个独立的 MCT基因(MCT1和MCT2)(在空间和时间上)独立发生 在出生后发育过程中；3)脑表达升高的动物 来自饮食操作的MCT对缺氧/缺血细胞的抵抗力更强 4)脑乳酸酸中毒与 缺氧/缺血诱导MCTs表达增加。特异性抗体 MCT1和MCT2的寡核苷酸探针将用于分析和 量化转运蛋白和信使核糖核酸。信使核糖核酸将由 核糖核酸酶保护试验和原位杂交。MCT蛋白 将通过免疫印迹检测和光和电子来确定 免疫细胞化学。巨噬细胞集落刺激因子在饮食中的表达 将检查改变和全脑前脑缺血。动物与 实验中增加的MCT水平将根据它们的能力进行评估 以抵抗全球前脑缺血后的神经损伤。这个 MCT1和MCT2的基因组序列将关闭并进行特征分析等 脑部MCT将被识别出来。这些拟议的研究将有助于 更好地了解细胞之间的代谢相互关系 大脑，因此可能导致 改善中风患者的治疗方法或预防措施 神经退行性疾病。

DESCRIPTION: Lactate and related monocarboxylic acids are important substrates and metabolic products of brain metabolism. Under conditions such as starvation, high fat consumption, and early development (newborn or suckling neonates), monocarboxylates such as lactate, pyruvate and ketone bodies may be extracted from the blood and used by the brain as fuels. Recent evidence suggests metabolic coupling occurs between astrocytes and neurons whereby lactate produced by astrocytes is utilized by neurons during neural activation. The overall objective of this proposal is to characterize the monocarboxylic acid transporters in brain and their role in blood-brain transport and cerebral metabolism. This includes molecular identification of the membrane proteins responsible for transporting monocarboxylic acids (lactic, pyruvic, acetoacetic and ^D- hydroxybutyric acids) across the plasma membranes of endothelial cells, astrocytes, and neurons; characterization of their cellular location, expression, regulation, and role in cerebral metabolism. The principal hypotheses to be tested are that: 1) the requisite monocarboxylate transporters (MCTs) for metabolic coupling between astrocytes and neurons are present in rat brain cortex, hippocampus and cerebellum; 2) upregulation of at least two separate MCT genes (MCT1 and MCT2) occurs independently (spatially and temporally) during postnatal development; 3) animals with elevated expression of brain MCTs from dietary manipulations are more resistant to hypoxic/ischemic cell damage than control animals; and 4) brain lactic acidosis associated with hypoxia/ischemia induces increased expression of MCTs. Specific antibodies and oligonucleotide probes for MCT1 and MCT2 will be used to analyze and quantify transporter proteins and mRNA. mRNA will be determined by ribonuclease protection assays and by in situ hybridization. MCT proteins will be determined by immunoblot detection and light and electron immunocytochemistry. The expression of MCTs in response to dietary alterations and global forebrain ischemia will be examined. Animals with experimentally increased levels of MCTs will be assessed for their ability to resist neurological damage following global forebrain ischemia. The genomic sequence of MCT1 and MCT2 will be closed and characterized and other brain MCTs will be identified. These proposed studies will contribute to a better understanding of the metabolic interrelationships among cells of the brain and therefore may lead to improved therapies, or preventive measures for patients with stroke or neurodegenerative disorders.