【摘要】 目的 探讨雷公藤内酯醇(TP)对阿尔茨海默病(AD)模型大鼠海马神经细胞凋亡及其相关蛋白表达的影响。方法 健康雄性SD大鼠随机分为对照组、模型组及用药组。模型组给予双侧海马各一次性注射凝聚态Aβ1-40,Morris水迷宫实验判断模型成功与否。对照组大鼠双侧海马注射等量生理盐水。用药组大鼠在模型制作成功后每日腹腔注射TP 0.4 mg/kg,共15 d。应用流式细胞仪、TUNEL染色、透射电镜技术检测各组大鼠海马神经细胞凋亡的变化,免疫组织化学法检测各组大鼠海马神经细胞细胞色素C和Bcl?2 蛋白表达的变化。结果 用药组大鼠海马神经细胞凋亡率较模型组明显降低(P<0.01),TUNEL染色阳性细胞数较模型组明显减少(P<0.01);用药组大鼠海马细胞色素C阳性产物数和平均光密度均较模型组明显减少P<0.01),Bcl?2阳性细胞数和平均光密度均较模型组明显增加(P<0.01)。结论 TP对AD模型大鼠海马神经细胞凋亡有抑制作用,其机制可能与TP增加AD模型大鼠海马神经细胞Bcl?2蛋白表达、减少细胞色素C的释放有关。
教师职称论文发表 中国论文网 g[zn s HSg中国论文网"d v5aqRCny'_【关键词】 雷公藤内酯醇;β?淀粉样蛋白;神经细胞凋亡;阿尔茨海默病
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{(}0%Li7fY`E6]v'WoG0 【Abstract】 Objective To explore the effect of triptolide(TP) on the neuronal apoptosis and the expression of apoptosis?related proteins in hippocampus of AD model rats. Methods Healthy male SD rats were randomly divided into control, AD model and TP?treated groups. The AD model group was made by bilateral microinjection of Aβ1?40 into hippocampus in rats and Morris water maze test was used to judge the models success or not. The control group was made by bilateral microinjection of normal saline into hippocampus in rats.The TP?treated group rats were administered TP (0.4 mg·kg-1·d-1) intraperitoneally after the AD model was made successfully. 15 days later,the changes of neuronal apoptosis in hippocampus of each group were observed with flow cytometry and TUNEL staining and transmission electron microscopy, and the changes of cytochrome C and Bcl?2 protein expression in hippocampus of each group were observed by immunohistochemical staining. Results Compared with those of the AD model group,the apoptosis rate of neurons and the cell number of TUNEL positive staining in hippocampus of the TP?treated group were significantly decreased(P<0.01). The number and average optical density of cytochrome c positive products in hippocampus of the TP?treated group were obviously lower than those of the AD model group (P<0.01), and the cell number and average optical density of Bcl?2 positive staining were obviously higher than those of the AD model group (P<0.01). Conclusions TP can inhibit the neuronal apoptosis in hippocampus of the AD model group.Its mechanism may concern increasing the Bcl?2 expression and reducing the release of cytochrome c in hippocampus of the AD model group.
[-} D5t/?:ts0 hWL4IMh#O8A0 【Key words】 Alzheimer′s disease;β?amyloid protein;Neuronal apoptosis;Triptolide
中国论文网#S [ sx}中国论文网C"R/l|-?Bu 凋亡介导准确的、程序性的神经细胞自然死亡,是中枢神经系统发育过程中神经细胞发生的重要生理过程。然而,过早凋亡和/或凋亡的调控失常与神经退行性变的发病机制有关,可导致各种慢性疾病发生,如阿尔茨海默病(AD) 〔1〕。β淀粉样蛋白(Aβ)的代谢异常和沉积是AD发生和发展的关键性因素。离体和在体实验表明Aβ与神经细胞凋亡关系密切,Aβ可诱导神经细胞凋亡。神经细胞凋亡被认为是AD中神经元大量丢失的主要原因之一〔2〕。因此,减轻Aβ诱导的神经细胞凋亡可改善AD的预后。最近的研究发现雷公藤内酯醇(TP)可通过抗炎和免疫抑制作用,减轻Aβ所致AD模型大鼠脑内的免疫炎症反应,改善AD大鼠的学习记忆能力〔3〕。本实验采用流式细胞术、TUNEL染色、透射电镜技术及免疫组织化学染色,研究TP对Aβ1?40所致AD 模型大鼠海马神经细胞凋亡及其相关蛋白表达的影响,为进一步阐明TP对AD模型大鼠神经细胞保护性作用及机制提供实验依据。
教师职称论文发表 中国论文网
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6c6b-P.q\0中国论文网Dbhz];H6T TP(纯度为99.8%,批号070929,福建省医学科学研究所,溶于4%丙二醇溶液中,经200目过滤器滤过除菌后备用);Aβ1-40(Sigma公司);TUNEL试剂盒(Promega公司);PI染色(BD公司);鼠抗细胞色素C和鼠抗Bcl?2单克隆抗体(Santa Cruz 公司);SP试剂盒(Zymed公司);DAB显色试剂盒(北京中杉公司)。
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x3v7O#bQ~0)GoB(It2g0 江湾Ⅰ型C 大鼠脑立体定位仪(上海川沙花木农机厂);微量进样器(上海安亭科学仪器厂);冰冻切片机YD?1508 Ⅲ(浙江金华益迪医疗设备厂);BD流式细胞仪FACSCalibur(美国BD公司);手术显微镜SXP?1C(上海医疗器械股份有限公司);Image?Pro Plus v 6.0显微图像分析系统(Media Cybernetics公司)。
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