去铁胺对脂多糖诱发的小鼠中枢神经炎症反应与记忆损伤的改善作用

发布时间：2018-05-23 15:37

本文选题：去铁胺 + 神经炎症反应　；参考：《中国人民解放军医学院》2015年硕士论文

【摘要】：第一部分脂多糖(LPS)脑室注射诱发认知功能障碍动物模型的建立目的探讨脂多糖单次脑室注射对C57小鼠认知功能的影响,以期建立中枢炎性相关的认知功能障碍的小鼠模型。方法将40只C57小鼠随机分为5组,分别为溶剂对照组与LPS 10ng、100ng、2000ng,5000ng剂量组,进行Morris水迷宫(MWM)实验。于第1-5日进行水迷宫空间获得性训练,第6日脑室单次分别给予LPS 0、10、100、2000、5000ng,第7-9日进行水迷宫空间探索实验与工作记忆检测。结果与溶剂对照组相比,脂多糖给药组均引起小鼠在Morris水迷宫实验中认知功能下降,其中2000ng LPS给药组分别引起水迷宫空间探索实验中小鼠穿台次数、平台周边路程、目标象限停留时间百分比及目标象限停留路程百分比均显著减少,工作记忆检测中登台潜伏期明显延长(P0.05)。小结单次LPS(2μg)(?)室注射可引起C57小鼠认知功能障碍,提示LPS脑室注射导致炎性损伤可以作为认知功能障碍的候选模型。第二部分去铁胺(DFO)对LPS诱发小鼠认知功能障碍的改善及机制目的探讨DFO对LPS诱发小鼠认知损伤的改善作用及机制。方法将48只C57小鼠随机分为6组,分别为溶剂对照组、LPS模型组与DFO 0.1μg、0.5μg、2.5μg、5μg治疗组,进行Morris水迷宫(MWM)实验以探索DFO对LPS诱发认知障碍的改善的最佳剂量。另将100只C57小鼠随机分为4四组：溶剂对照组、DFO组、LPS组和LPS+DFO组。0.5μg DFO于2μg LPS脑室注射前3日给药,对照组给予等量人工脑脊液,给药方式均为侧脑室注射。每日行为学实验或给药前进行小鼠体质量测量。LPS给药6h、24h、48h、72h后将小鼠行心脏灌流并取脑,通过检测海马组织中小胶质细胞状态、IL-1p和TNF-α水平、细胞凋亡蛋白caspase-3与糖原合酶激酶3β(glycogen synthase kinase 3β, GSK3β)表达、超氧化物歧化酶(superoxide dismutase, SOD)和丙二醛(malondialdehyde,MDA)活性及海马组织铁代谢状态的改变等指标以评估LPS引起的小鼠海马损伤及DFO的神经保护作用及可能机制。结果DFO预给药明显改善了LPS引起的小鼠在Morris水迷宫实验中认知样行为的下降,而并未对自发活动造成明显改变。DFO减轻了LPS诱发的海马组织小胶质细胞激活与炎症因子IL-1β和TNF-α的上升,同时预防性减弱了caspase-3蛋白的(P0.05)表达增多、GSK3β激活及MDA与SOD水平的改变。DFO明显逆转LPS引起的海马组织铁沉积及铁代谢相关蛋白的表达水平变化(P0.05)。小结DFO通过阻止神经细胞内铁沉积,减弱海马神经组织炎症反应、氧化应激与凋亡等病理进程,最终对LPS诱发的小鼠认知功能障碍起到改善作用。结论：LPS脑室注射触发小鼠中枢神经炎症级联反应与脑铁沉积,从而导致短暂性认知功能障碍；DFO可对脂多糖诱发的小鼠神经炎症反应与记忆损伤起到保护作用,这一作用可能与维持脑铁含量较低水平从而起到的神经保护性作用及应激反应与凋亡水平的改善有关。
[Abstract]:Part one: establishment of animal model of cognitive dysfunction induced by intraventricular injection of lipopolysaccharide (LPS) objective to investigate the effect of single intraventricular injection of lipopolysaccharide on cognitive function of C57 mice in order to establish a model of central inflammatory related cognitive dysfunction. Methods Forty C57 mice were randomly divided into 5 groups: solvent control group and LPS 10ng / 100ng / 100ng / 100ng / kg group. The Morris water labyrinth test was carried out. The water labyrinth spatial acquisition training was conducted on the 1st to 5th day, the sixth ventricle was given LPS 010100 / 2000000ng, and the water labyrinth spatial exploration experiment and working memory test were carried out on the 7th and 9th days. Results compared with the solvent control group, the lipopolysaccharide group caused the decrease of cognitive function in the Morris water maze test, and the 2000ng LPS group caused the mice to penetrate the platform and the distance around the platform in the water maze space exploration experiment. The percentage of target quadrant residence time and the percentage of target quadrant residence distance were significantly reduced, and the latency of stage entry was significantly prolonged in working memory testing (WMA). Single LPS(2 渭 g) Ventricular injection could induce cognitive dysfunction in C57 mice, suggesting that LPS injection could be used as a candidate model for cognitive dysfunction. The second part: the improvement and mechanism of LPS induced cognitive dysfunction in mice by deferoxamine DFOObjective to investigate the effect and mechanism of DFO on LPS induced cognitive impairment in mice. Methods Forty-eight C57 mice were randomly divided into 6 groups: the solvent control group and the DFO 0.1 渭 g, 0.5 渭 g or 2.5 渭 g, 5 渭 g treatment group. The Morris water maze test was performed to explore the best dose of DFO to improve the cognitive impairment induced by LPS. In addition, 100 C57 mice were randomly divided into four groups: the solvent control group and the LPS DFO group received intraventricular injection of 0.5 渭 g DFO 3 days before intracerebroventricular injection, and the control group was given the same amount of artificial cerebrospinal fluid (ACSF), all of which were administered by intracerebroventricular injection. The body mass of mice was measured by daily behavioral experiment or before administration of LPS. The mice were perfused with heart for 72 h after administration of LPS for 24 h or 48 h. The levels of IL-1p and TNF- 伪 in hippocampal tissue were measured by detecting the status of mesomatous glial cells in hippocampus. The expression of apoptotic protein caspase-3 and glycogen synthase kinase 3 尾 (GSK3 尾) was observed. The activity of superoxide dismutase (SOD) and malondialdehyde (malondialdehyde) MDAs and the changes of iron metabolism in hippocampal tissue were used to evaluate the neuroprotective effect of LPS and DFO in mice. Results DFO preadministration significantly improved the reduction of cognitive-like behavior in mice induced by LPS in Morris water maze test. There was no obvious change in spontaneous activity. DFO alleviated the activation of microglia and the increase of inflammatory cytokines IL-1 尾 and TNF- 伪 in hippocampus induced by LPS. At the same time, the expression of caspase-3 protein increased and GSK3 尾 activation and the changes of MDA and SOD levels. DFO significantly reversed the changes of iron deposition and iron metabolism-related protein expression in hippocampus induced by LPS. Conclusion DFO can improve the cognitive function of mice induced by LPS by preventing iron deposition in nerve cells, weakening inflammatory reaction, oxidative stress and apoptosis in hippocampal nerve tissue. Conclusion the neuroinflammatory cascade reaction and iron deposition in the central nervous system were triggered by intraventricular injection of 10% LPS in mice, which resulted in transient cognitive impairment. DFO can protect the neuroinflammatory response and memory impairment induced by lipopolysaccharide in mice. This effect may be related to the neuroprotective effect of maintaining a low level of iron in the brain and the improvement of the level of apoptosis and the stress response.
【学位授予单位】：中国人民解放军医学院
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R614

【共引文献】