GANGLIOSIDE-TROPHIC FACTOR--INTERACTIVE MECHANISM

这个项目的长期目标是在分子水平上理解 阐明创伤后神经再生的相关机制。 严重脊髓损伤后功能恢复的关键因素 是轴突萌发(神经发生)。实验证据表明 几种营养因子，其中一种是神经节苷脂，可以刺激 体内和体外的神经发生。这已经产生了 对神经节苷脂可能用作治疗的兴趣很大 用于临床治疗脊髓损伤的药物。尽管 神经节苷脂促进神经再生的分子机制 未知，我们和其他人的结果表明神经节苷脂 会影响整个细胞和破碎细胞中的蛋白质磷酸化 准备工作。本提案中描述的实验旨在 测试我们关于神经节苷脂作用于 调控神经发生与神经元增殖 特定蛋白质的磷酸化状态。我们将推出的主要模型 使用的是SH-SY5Y神经母细胞瘤细胞系，但确证结果 将寻求使用PC12电池进行一些实验。首先，我们将研究 神经节苷脂与血小板衍化生长的相互作用 胰岛素样生长因子-I(IGF-I)、胰岛素样生长因子(PDGF-I)、胰岛素对SH-1的影响 SY5Y细胞增殖。第二，我们将考察 不同神经节苷脂对神经生长因子刺激的SH-SY5Y细胞神经再生的影响 在PDGF、IGF-I和胰岛素存在的情况下。第三，我们将确定 神经节苷脂对三种不同神经节苷脂的不同作用 我们提出的激酶系统在这些过程中起着至关重要的作用 生物过程：a)PDGF、IGF-I和IGF-I刺激的酪氨酸激酶 胰岛素；b)蛋白激酶C；c)cAMP依赖的蛋白激酶。结果 由这些实验产生的结果应该能相当深入地了解 神经节苷脂促进神经发生的分子机制。 这些知识对理解神经学有相当大的价值。 在分子水平上研究再生和设计新的 脊髓损伤患者的治疗策略。

The long range goal of this project is to understand at the molecular level the mechanisms involved in neural regeneration following trauma. A critical aspect of functional recovery from severe spinal cord injury is axonal sprouting (neuritogenesis). Experimental evidence indicates that several trophic factors, one of which is ganglioside, can stimulate neuritogenesis both in vivo and in vitro. This has generated considerable interest in the possible use of gangliosides as therapeutic agents for clinical treatment of spinal cord injuries. Although the molecular mechanisms through which gangliosides promote neuritogenesis are not known, results of ours and others have shown that gangliosides can affect protein phosphorylation in whole cell and broken cell preparations. Experiments described in this proposal were designed to test our general hypothesis that gangliosides exert their effects on neuritogenesis and neuronal proliferation by modulating the phosphorylation states of specific proteins. The main model that we will use is the SH-SY5Y neuroblastoma cell lines, but confirmatory results of some experiments will be sought using PC12 cells. First, we will study the interactive effects of gangliosides with platelet-derived growth factor (PDGF), insulin-like growth factor-I (IGF-I), and insulin on SH- SY5Y cell proliferation. Second, we will examine the effects of different gangliosides on NGF-stimulated neuritogenesis of SH-SY5Y cells in the presence of PDGF, IGF-I, and insulin. third, we will determine the differential effects of specific gangliosides on three different kinase systems which we propose are critically involved in these biological processes: a) Tyrosine kinase stimulated by PDGF, IGF-I and insulin; b) Protein kinase-C; c) cAMP-dependent protein kinase. Results generated by these experiments should yield considerable insight into the molecular mechanisms through which gangliosides promote neuritogenesis. This knowledge will be of considerable value in understanding neural regeneration studied at the molecular level and in designing new therapeutic strategies for treatment of spinal cord injured patients.