SOURCES AND EFFECTS OF REACTIVE OXYGEN INTERMEDIATES IN THE BRAIN

大脑中活性氧中间体的来源和作用

• 批准号: 2579521
• 负责人: D L GILBERT
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF NEUROLOGICAL DISORDERS AND STROKE
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2579521
• 关键词: amyloid proteins; anions; astrocytes; cysteine; enzyme inhibitors; free radical oxygen; hamsters; human tissue; hydroxyl radical; laboratory mouse; mesencephalon; microglia; neurochemistry; nitric oxide; oxidative stress; superoxides; tissue /cell culture

Experiments have been performed on microglia and astrocytes cultured from cerebral cortices of mice and hamsters. We have previously demonstrated that activated rat microglia cells produce the reactive oxygen species (ROS), superoxide radical anion, within a few hours after stimulation and nitric oxide, after a period of about 10 hours to several days. Previously, we have also shown that hamster microglia releases little or no nitric oxide. We have now shown that activated mice microglia also produce nitric oxide. We have continued these studies using normal human microglia, obtained from biopsy samples, and have shown that these human microglia produce little or no nitric oxide. We have tested more than 24 chemical activators including beta-amyloid (1- 40) to determine if any one of them could activate hamster microglia to produce nitric oxide, Neither hamster nor human microglia produce NO. Human microglia have only been tested with 6 different chemical activators to determine if any of these would be successful techniques for producing nitric oxide. Thus, we have now shown that hamster microglia are similar to human microglia, and that for animal disease models in which microglia participate, it might be better to use hamsters instead of rats and mice. Since arginase catalyses the breakdown of arginine into urea and ornithine, we tested whether the inhibition of this pathway by (+)-S-2-amino-5-iodoacetamidopentanoic acid (AIAP), an inhibitor of the enzyme, arginase, could possibly produce nitric oxide production in the hamster microglia. Preliminary experiments. indicated that this inhibition did produce nitric oxide from stimulated hamster microglia.The B103 cells, derived from neuroblastoma line, are exceptional in their lack of beta-amyloid precursor protein. The cells have been grown in the presence of hydrogen peroxide as a oxidative stress. We are currently accessing the damage produced by this oxidative stress. We plan to give the same oxidative stress to these cells in the presence of added beta-amyloid precursor protein and determine if this is an antioxidant.

在培养的小胶质细胞和星形胶质细胞上进行了实验。 来自小鼠和仓鼠的大脑皮层。我们之前已经 证明了激活的大鼠小胶质细胞会产生反应性 氧物种(ROS)，超氧阴离子，在几个小时后 刺激和一氧化氮，经过约10小时至数小时 几天。此前，我们还展示了仓鼠释放的小胶质细胞 很少或根本没有一氧化氮。我们现在已经证明，被激活的小鼠 小胶质细胞也会产生一氧化氮。我们一直在继续这些研究 使用从活检样本中获得的正常人类小胶质细胞，并具有 研究表明，这些人类小胶质细胞产生的一氧化氮很少或根本不产生。我们 已经测试了超过24种化学激活剂，包括β-淀粉样蛋白(1- 40)确定它们中的任何一个是否可以激活仓鼠小胶质细胞以 产生一氧化氮，无论是仓鼠还是人类小胶质细胞都不会产生NO。 人类小胶质细胞只用6种不同的化学物质进行了测试 激活者，以确定这些技术中是否有任何一种是成功的技术 用来产生一氧化氮。因此，我们现在展示了仓鼠 小胶质细胞与人类的小胶质细胞相似，也与动物疾病的小胶质细胞相似 在小胶质细胞参与的模型中，使用 仓鼠，而不是老鼠和老鼠。因为精氨酸酶催化分解 将精氨酸转化为尿素和鸟氨酸，我们测试是否有抑制作用 (+)-S-2-氨基-5-碘乙酰氨基戊酸(AIAP)， 这种酶的抑制剂精氨酸酶可能会产生一氧化氮。 在仓鼠的小胶质细胞中产生。初步实验。示出 这种抑制确实会从受刺激的仓鼠中产生一氧化氮 小胶质细胞。来自神经母细胞瘤系的B103细胞是 特别是他们缺乏β-淀粉样前体蛋白。这些细胞 是在过氧化氢存在的情况下作为氧化剂生长的 压力。我们目前正在访问由这种氧化作用产生的损害 压力。我们计划给这些细胞同样的氧化应激 是否存在添加的β-淀粉样前体蛋白并确定这是否 是一种抗氧化剂。