雷帕霉素抑制镉诱导小鼠脑神经细胞氧化应激和mTOR通路激活抗凋亡机理研究

发布时间：2018-04-11 16:58

本文选题：镉 + 小鼠　；参考：《南京师范大学》2013年硕士论文

【摘要】：本研究通过建立亚急性镉染毒诱导小鼠模型,运用HE染色、透射电镜、免疫组化和Western blotting等技术方法,研究了雷帕霉素在抗镉诱导小鼠脑神经细胞氧化应激和凋亡中的保护作用,探讨雷帕霉素抑制镉诱导小鼠脑组织mTOR通路激活抗凋亡机理,为雷帕霉素在防止镉诱导的神经变性疾病提供理论依据和科学指导。结果如下： 1雷帕霉素抑制镉诱导小鼠脑神经细胞氧化应激发挥抗凋亡保护作用 36只成年健康ICR雄性小鼠,实验分为对照组(0.9%生理盐水)、雷帕霉素处理组(按7.5mg/kg体重)、2个CdCl2处理组(分别按0.5和1mg/kg体重)、2个雷帕霉素与CdCl2联合处理组,共6组。实验给药采用腹腔注射方式,实验周期11天。HE染色和透射电镜分别观察脑组织学和超微结构变化,生化分析脑组织ROS、GSH、CAT水平变化,TUNEL染色评价脑神经细胞凋亡状态。结果显示：镉染毒小鼠脑颞叶皮层出现明显的混乱,海马区细胞排列松散,脑神经元线粒体肿胀和内嵴的断裂,而雷帕霉素能够明显削弱和保护这种改变。镉诱发脑组织ROS升高以及GSH含量和CAT活性降低,这被雷帕霉素明显改善。镉诱导大脑皮层和海马组织TUNEL阳性神经细胞数量增加也被雷帕霉素显著抑制。提示雷帕霉素可以通过抑制镉诱导小鼠脑组织神经细胞氧化应激发挥抗凋亡保护作用。 2雷帕霉素抑制镉诱导小鼠脑组织mTOR通路激活发挥抗凋亡保护作用 36只成年健康ICR雄性小鼠,实验分为对照组(0.9%生理盐水)、雷帕霉素处理组(按7.5mg/kg体重)、2个CdCl2处理组(分别按0.5和1mg/kg体重)、2个雷帕霉素与CdCl2联合处理组,共6组。实验给药采用腹腔注射方式,实验周期11天。免疫组化分析4E-BP1磷酸化表现,Western blot分析Akt、S6K1、4E-BP1和caspase-3蛋白表达。结果显示：免疫组化分析显示,镉染毒小鼠大脑皮层及海马CA1区磷酸化4E-BP1(Thr70)阳性细胞数量明显增加,Western blot分析展示镉诱导脑组织Akt、mTOR介导的S6K1和4E-BP1磷酸化以及cleaved-caspase-3增加,雷帕霉素明显地抑制这些信号分子改变。提示：雷帕霉素通过抑制镉诱导小鼠脑组织mTOR通路激活发挥抗凋亡保护作用。
[Abstract]:In this study, through the establishment of subacute cadmium induced mouse model, using HE staining, transmission electron microscopy, immunohistochemistry and Western blotting methods of rapamycin in anti cadmium induced protective effect in mouse brain cells to oxidative stress and apoptosis, explore the rapamycin inhibited activation of anti apoptotic mechanism induced by cadmium in mice brain tissue mTOR pathways, provide theoretical basis and scientific guidance for prevention of rapamycin in neurodegenerative diseases induced by cadmium. The results are as follows:
1 the inhibitory effect of rapamycin on the apoptosis of cerebral nerve cells induced by cadmium induced cadmium in mice
36 healthy adult male ICR mice were divided into control group (0.9% saline), rapamycin treatment group (7.5mg/kg weight), 2 CdCl2 (treatment group respectively by 0.5 and 1mg/kg body weight), combined treatment group 2 rapamycin and CdCl2, a total of 6 groups. The experimental drug by abdominal cavity injection. The experimental period of 11 days,.HE staining and transmission electron microscope were used to observe the brain histological and ultrastructural changes, biochemical analysis of brain tissue ROS, GSH, CAT level, TUNEL staining were used to evaluate the brain nerve cell apoptosis. Results showed that the apparent chaos of mice exposed to cadmium cerebral temporal lobe cortex, hippocampus cells loose, fracture of brain neurons mitochondria swelling and cristae, and rapamycin can obviously weaken and protect the brain tissue induced by cadmium changes. ROS increased and the content of GSH and CAT decreased, which is rapamycin significantly improved. The cerebral cortex and hippocampus of T induced by cadmium Increased number of UNEL positive neurons was also significantly inhibited by rapamycin, indicating that rapamycin can inhibit the apoptosis of neurons in cadmium induced brain tissue by stimulating the apoptosis of mice brain tissue.
2 the inhibitory effect of rapamycin on the activation of mTOR pathway in brain tissue induced by cadmium induced cadmium in mice
36 healthy adult male ICR mice were divided into control group (0.9% saline), rapamycin treatment group (7.5mg/kg weight), 2 CdCl2 (treatment group respectively by 0.5 and 1mg/kg body weight), combined treatment group 2 rapamycin and CdCl2, a total of 6 groups. The experimental drug by abdominal cavity injection. The experiment lasted for 11 days. Immunohistochemical analysis of 4E-BP1 phosphorylation, Western blot analysis of Akt, S6K1,4E-BP1 and caspase-3 protein expression. Results: immunohistochemical analysis showed that cadmium phosphate in mice cerebral cortex and hippocampus CA1 region of the 4E-BP1 (Thr70) positive cells increased significantly, Western blot analysis showed brain tissue induced by cadmium in Akt, mTOR mediated S6K1 and 4E-BP1 phosphorylation and increased cleaved-caspase-3, rapamycin significantly inhibited these changes. Note: rapamycin signaling molecules play anti apoptotic induced activation of mouse brain tissue mTOR pathway through the inhibition of cadmium Protective effect.

【学位授予单位】：南京师范大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：R114

【共引文献】