家族型与散发型阿尔茨海默病动物模型的对比分析

发布时间：2019-02-27 17:24

【摘要】：目的：随着我国老龄人口数量的日益增多，阿尔茨海默病（Alzheimer’s disease，AD)这种主要在老年群体中出现的疾病,将会给社会和家庭带来极大危害。AD分为散发型（SAD）和家族型（FAD）。大部分AD患者为散发型，病因可能来自多个因素，包括环境，基因和代谢等。家族型是由于早老素或是APP的突变引起。实验中最常应用的AD鼠模型是三转基因鼠模型（3×Tg-AD），它可以使大脑中出现突变的早老素1，APP和过表达的磷酸化tau蛋白，因此代表了家族型AD鼠模型。散发型AD鼠模型可以通过往小鼠脑室内注射链霉素（STZ）实现。尽管这两类模型已经广泛引用于科研中，但是两者之间的差异并没有被报道。我们实验的目的是从APP形成/tau蛋白，突触功能，凋亡和自嗜，AD相关蛋白激酶，葡萄糖代谢，胰岛素信号、mTOR通路以及炎症等八个方面，筛选出不同类型的AD鼠模型参与其分子生物学机制的基因和蛋白表达的异同，对AD的研究和药物的发展有十分重要的社会意义和不可估量的经济价值。方法：我们应用基因芯片技术，比较不同类型中小鼠的海马和皮质中84个AD相关基因的表达情况。这些基因涉及APP形成/tau蛋白，突触功能，，凋亡和自嗜，AD相关蛋白激酶，葡萄糖代谢，胰岛素信号以及mTOR通路等。本研究应用PCR芯片数据分析系统处理研究不同类型AD鼠基因的表达差异，同时应用蛋白印迹技术观察小鼠脑组织炎症改变情况，进一步分析不同模型之间蛋白表达差异。我们还将冰冻的小鼠脑组织切片，进行免疫组化染色，通过光镜观察病理情况，比较不同区域脑组织与蛋白表达的关系，对蛋白印迹的结果进行验证。结果：我们发现在两种小鼠模型中，大约有20个来自上面分类中的基因有差异性表达。一些基因的改变和先前在AD大脑里面观察结果是一致的。在两种小鼠模型中，这些差异性基因的表达是减少或者是趋于下降的。两种小鼠模型的大脑皮质中基因表达的多样性更加明显。在三转基因鼠中，更多的相关突触功能的基因是下调的，反之，在STZ注射鼠中，更多的相关胰岛素信号和葡萄糖代谢的基因是下调的。蛋白印迹技术可见两组小鼠大脑中都有不同程度炎症发生，存在蛋白差异表达。STZ注射鼠中炎症发生的程度比三转基因小鼠多。免疫组化技术进行验证，发现蛋白表达情况和以上结果一致，并且发现两组小鼠中海马区域的炎症反应要高于其他区域。结论：本课题阐述了STZ注射鼠和三转基因鼠之间基因表达的相同和不同处，也为两种模型中AD相关基因表达的改变提供了详细的介绍。这种高通量检测基因的实验模式，为AD在基因水平的研究奠定了基础。同时联合蛋白印迹技术和免疫组化等多项实验技术，通过APP形成，tau蛋白/细胞骨架，突触功能，凋亡和自嗜，AD相关蛋白激酶，葡萄糖代谢，胰岛素信号、mTOR通路及炎症等多方面的研究，筛选出参与不同类型AD鼠模型分子生物学机制的基因和蛋白的异同，为阿尔茨海默病的研究提供了新的思路，对AD的研究和药物的发展有重大意义。
[Abstract]:Objective: With the increasing number of aging population in our country, the disease of Alzheimer's disease (AD), which is mainly in the elderly population, will bring great harm to the society and the family. AD is divided into an emission type (SAD) and a family type (FAD). Most of the AD patients are sporadic, and the cause may come from multiple factors, including the environment, gene and metabolism, and so on. The family type is caused by an early age or a mutation in the APP. The most commonly used model of AD mice in the experiment is a three-transgenic mouse model (3-GTg-AD), which can cause a mutation in the brain of 1, APP, and overexpressed phosphorylated tau proteins, thus representing a family-type AD mouse model. The sporadic AD mouse model can be achieved by injecting streptomycin (STZ) into the mouse brain. Although the two models have been widely cited in scientific research, the difference between the two models is not reported. The purpose of our experiment is to form the/ tau protein, the synaptic function, the apoptosis and the self-, AD-related protein kinase, the glucose metabolism, the insulin signal, the mTOR pathway, and the inflammation in eight aspects, The similarities and differences of gene and protein expression of different type of AD mouse model in molecular biological mechanism were selected, and the research of AD and the development of drug were of great social significance and inestimable economic value. Methods: We applied gene chip technique to compare the expression of 84 AD-related genes in the hippocampus and cortex of different types of mice. Conditions. These genes involved APP-forming/ tau protein, synaptic function, apoptosis and self-, AD-related protein kinase, glucose metabolism, insulin signal, and mTOR pathway In this study, the difference of expression of different types of AD mice was studied by PCR chip data analysis system, and the expression of protein in different models was further analyzed by using the Western blot technique. In addition, the frozen mouse brain tissue was cut, the immunohistochemical staining was carried out, the pathological condition was observed by light microscope, the relationship between the expression of brain and protein in different regions was compared, and the results of the Western blot were tested. The results: We found that in two mouse models, there were about 20 genes from the above classification. Sex expression. The changes in some genes and the previous observations in the AD brain are In two mouse models, the expression of these difference genes is reduced or tends to Down. The diversity of gene expression in the cerebral cortex of the two mouse models It is obvious that in the three transgenic mice, more of the genes associated with the synaptic function are down-regulated, whereas in the STZ mice, more of the genes associated with the insulin signal and the glucose metabolism are Down-regulation. Western blot showed that there were different levels of inflammation in the brain of both groups, and there was a protein difference. The degree of inflammation in the mice with STZ injection is higher than that of the three transgenes The expression of the protein was found to be consistent with the above results, and the inflammatory response of the hippocampus in the two groups was found to be higher than that of the two groups. Conclusion: This topic describes the same and different positions of the gene expression between the STZ injection and the three transgenic mice, and also provides for the change of the expression of the AD-related genes in the two models. The experimental mode of this high-throughput detection gene is the study of the gene level of AD. It has laid a foundation for many experiments, such as APP formation, tau protein/ cytoskeleton, synaptic function, apoptosis and self-, AD-related protein kinase, glucose metabolism, insulin signal, mTOR pathway and inflammation. In this study, the similarities and differences of the genes and proteins involved in the molecular biological mechanism of different types of AD mice were selected, and a new thought was provided for the study of Alzheimer's disease, and the research of AD and the development of drugs were provided.
【学位授予单位】：吉林大学
【学位级别】：博士
【学位授予年份】：2013
【分类号】：R749.16;R-332

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