GLIAL NO SYNTHASE--REGULATION OF EXPRESSION

胶质细胞无合酶--表达调节

• 批准号: 2037640
• 负责人: Douglas L. Feinstein
• 金额: $ 13.83万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-04-01 至 1997-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2037640
• 关键词: Animalia; antisense nucleic acid; astrocytes; beta antiadrenergic agent; cytokine; enzyme activity; enzyme induction /repression; lipopolysaccharides; neuropharmacology; nitric oxide; nitric oxide synthase; oligonucleotides; stress proteins; tissue /cell culture; transcription factor

DESCRIPTION (Applicant's Abstract) In brain, activation of astrocytes can induce calcium independent nitric oxide synthase (NOS-2) expression, which can contribute to the damage during ischemia, demyelinating disease, and viral infection. The applicants have previously characterized factors which activate astroglial NOS-2 expression, and two methods for potently blocking that expression, namely stimulation of b-ARs, and pretreatment with inhibitors of protein tyrosine kinases. They have also found that heat shock of glial cells reduces NOS-2 expression. Whether these methods of suppression represent distinct mechanisms, or share common features, is not known. Since activation of the transcription factor NFkB is required for NOS-2 expression, it is possible that all three suppressive means interfere with NFkB activation. This grant therefore proposes to test and characterize NFkB activation in astrocytes as it relates to NOS-2 induction. Differential NFkB activation by different inducers and/or in different cell types (e.g. astrocytes versus C6 cells) may explain differences in levels of NOS-2 induction. Since protein phosphorylation plays a key role in NFkB activation, the applicants will test if NE effects are mediated via a protein kinase, and if so if that kinase modifies NFkB activation. They will also test if NE induces IkB expression. They will fully characterize the heat shock response in astrocyte and C6 cells with the purpose of defining which heat shock proteins can block NOS-2 induction, and if that is due to blocking NFkB activation. They will test if heat shock proteins physically bind to the NFkB and/or IkB proteins, if they block IkB phosphorylation and/or degradation, or if they simply block NFkB movement into the nucleus. They will test if NE effects are due in part to induction of heat shock proteins. Some experiments (e.g. heat shock) will be carried out in animals to test if this suppressive method also works in vivo. These experiments will define multiple pathways to block NOS-2 expression that may be useful in preventing pathological NOS-2 expression in brain.

描述（申请人的摘要）在大脑中，星形胶质细胞的激活可以 诱导钙依赖性一氧化氮合酶 (NOS-2) 表达， 可能会导致缺血、脱髓鞘疾病和 病毒感染。 申请人之前已描述了以下因素： 激活星形胶质细胞 NOS-2 表达，以及两种有效阻断的方法 该表达，即 b-AR 的刺激，以及用 蛋白酪氨酸激酶抑制剂。 他们还发现，热 神经胶质细胞的休克降低了 NOS-2 的表达。 这些方法是否 抑制代表不同的机制，或具有共同的特征，但不是 已知。 由于转录因子 NFkB 的激活是 NOS-2表达，有可能所有三种抑制手段都会干扰 与 NFkB 激活。 因此，这笔赠款建议测试和 描述星形胶质细胞中 NFkB 激活的特征，因为它与 NOS-2 诱导相关。 不同诱导剂和/或不同细胞中的差异化 NFkB 激活 类型（例如星形胶质细胞与 C6 细胞）可以解释 NOS-2诱导。 由于蛋白质磷酸化在 NFkB 中起着关键作用 激活后，申请人将测试 NE 效应是否通过 蛋白激酶，如果是的话，该激酶是否会改变 NFkB 的激活。 他们 还将测试 NE 是否诱导 IkB 表达。 他们将充分表征 星形胶质细胞和 C6 细胞的热休克反应，目的是 确定哪些热休克蛋白可以阻断 NOS-2 诱导，如果是 由于阻断 NFkB 激活。 他们将测试热休克蛋白是否 与 NFkB 和/或 IkB 蛋白物理结合（如果它们阻断 IkB） 磷酸化和/或降解，或者它们只是阻止 NFkB 运动 进入细胞核。 他们将测试 NE 效应是否部分归因于感应 热休克蛋白。 将进行一些实验（例如热休克） 在动物身上测试这种抑制方法是否也能在体内发挥作用。 这些 实验将确定多种途径来阻断 NOS-2 的表达，这可能 有助于预防大脑中病理性 NOS-2 表达。