神经RAGE基因缺陷对AGEs诱导突触损伤保护机理的研究

发布时间：2018-01-26 20:26

本文关键词： AGEs RAGE LTP 信号通路　出处：《兰州大学》2014年硕士论文　论文类型：学位论文

【摘要】：突触的退化是老龄化及老龄化相关疾病(包括老年痴呆AD)的早期特征。糖代谢终末产物-AGEs的积累与老龄化有关,蛋白质或脂类非酶糖基化(或者氧化)反应形成AGEs的初级产物,之后,逐渐积累形成AGEs。尤其对糖尿病、AD患者,体内血糖的持高和神经退化进一步加速了AGEs形成,影响大脑神经系统,导致细胞功能紊乱。RAGE,即AGEs的受体,它是细胞表面分子免疫球蛋白超家族成员,同时也是目前研究最多,AGEs与RAGE相互作用,引发多种疾病。本论文研究神经RAGE基因缺失对AGEs诱导突触损伤的保护机理。我们以野生型小鼠(WT)作为参照,选用RAGE基因全身敲除(RKO),大脑神经中枢敲除RAGE基因(NRKO),神经元内端RAGE基因缺失(DN-RAGE)的三种转基因小鼠,通过以下方法进行对比研究：(1)利用电生理技术检测小鼠海马CA1区的LTP；(2)利用抗原抗体反应,采用荧光免疫技术表征组织或细胞内抗原物质,对海马区的脑片、相应神经元染色,最后由共聚焦显微镜判定；(3)借助凝胶层析法分析AGEs相应蛋白(如RAGE、P38, ERK, GSK, JNK等)的表达强弱。上述几种表征方法所得实验结果是一致的,我们可以确定：AGEs的受体-RAGE缺失,可以规避AGEs与RAGE结合对LTP的损害及减少突触数量。此外,我们还尝试多种相应蛋白(例如P38, ERK, GSK, JNK等)及蛋白抑制剂,进一步研究AGEs与受体RAGE的信号通路,最终确定P38蛋白在AGEs诱导突触损伤中起到了介导作用。实验结果显示神经受体蛋白RAGE是AGEs引发突触功能紊乱的信号传感器。由此,我们发现了AGEs导致突触受损的新机制：AGEs与受体RAGE结合,激活神经蛋白P-38打开信号通路进而导致突触损伤；所以,阻止受体RAGE与其配体的结合,可以作为治疗老年相关神经疾病的一个靶点。
[Abstract]:Synaptic degeneration is an early feature of aging and age-related diseases, including Alzheimer's disease (AD). The accumulation of AGEs, the end product of glucose metabolism, is associated with aging. Nonenzymatic glycosylation (or oxidation) of proteins or lipids forms the primary product of AGEs, and then accumulates to form ages, especially in AD patients with diabetes mellitus. The hyperglycemia and neurodegeneration in vivo further accelerate the formation of AGEs, affect the brain nervous system, and lead to cell dysfunction. RAGE, the receptor of AGEs. It is a member of the cell surface molecular immunoglobulin superfamily, and it is also the most studied interaction between ages and RAGE, which causes many diseases. In this study, we studied the protective mechanism of neural RAGE gene deletion on synaptic injury induced by AGEs. We selected RAGE gene knockout as a reference for wild-type mice. Three kinds of transgenic mice with RAGE gene knockout and RAGE gene deletion at the inner end of the neuron (DN-RAGE). The electrophysiological technique was used to detect the CA1 in the hippocampus of mice. (2) the antigen-antibody reaction was used to characterize the antigens in tissues or cells by fluorescence immunoassay, and the corresponding neurons were stained in the brain slices of the hippocampus, which were finally determined by confocal microscopy. The corresponding proteins of AGEs (such as Rage P38, ERK, GSK) were analyzed by gel chromatography. The results of the above methods are consistent. We can confirm the deletion of the receptor-rage of 1% ages. We can avoid the damage caused by AGEs and RAGE binding to LTP and reduce the number of synapses. In addition, we try a variety of corresponding proteins (such as P38, ERK, GSK). JNK et al.) and protein inhibitors to further study the signaling pathway between AGEs and receptor RAGE, and finally confirm that P38 protein plays a mediating role in AGEs induced synaptic injury. The results show that the neural receptor protein RAGE is a signal sensor of synaptic dysfunction induced by AGEs. We have found a new mechanism of synaptic damage caused by AGEs: Ages binding to receptor RAGE, activating neuroprotein P-38 to open signal pathway and leading to synaptic injury. Therefore, blocking the binding of receptor RAGE to its ligand may be a target for the treatment of geriatric neuropathies.
【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R741

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