链脲佐菌素对APP/PS1转基因小鼠脑内糖原合成酶-3α活性的影响

目的观察链脲佐菌素(streptozotocin,STZ)诱导的实验性糖尿病对APP/PS1转基因小鼠脑组织中糖原合成酶-3α(GSK-3α)蛋白活性的影响。方法 3月龄APP/PS1转基因小鼠腹腔内注射STZ建立实验性糖尿病模型。使用电子天平和便携式血糖仪定期检测小鼠体重和血糖的变化。应用免疫组织化学方法和western blotting方法检测AD转基因小鼠脑组织中p-GSK-3α和GSK-3α的蛋白表达。结果动物饲养20W后,与APP/PS1转基因小鼠比较,STZ组转基因小鼠体重下降(P<0.05),血糖则明显升高(P<0.01),提示糖尿病模型诱导成功。Western blotting结果显示,STZ组APP/PS1转基因小鼠脑内p-GSK-3α蛋白表达水平较APP/PS1转基因小鼠明显降低(P<0.01),而总GSK-3α蛋白没有变化(P>0.05),两者的比值p-GSK-3α/GSK-3α下降49%(P<0.01)。免疫组化染色显示,STZ组转基因小鼠大脑皮层神经元内p-GSK-3α阳性表达明显低于转基因小鼠。结论 STZ上调APP/PS1转基因小鼠脑组织内GSK-3α蛋白活性。     

β-石竹烯通过作用于HMGB1 / TLR4 / NF鄄资B 通路减轻小鼠局灶性脑缺血再灌注损伤

目的:研究β-石竹烯(β-caryophyllene,BCP)对脑缺血再灌注损伤(Cerebral ischemia-reperfusion,CIR)小鼠的保护作用及可能的机制。方法:将C57BL/6 小鼠随机分组为假手术组(Sham)、模型组(CIR)、β-石竹烯组(62、124、248mg/ kg)。采用线栓法建立小鼠CIR 损伤模型,缺血1 h,再灌注24 h 后,进行神经行为学评分和脑梗死体积测定;TUNEL 法观察CIR 后缺血区神经细胞的死亡情况;Western blot 法检测脑组织中TLR4 和NF-κB(p65)蛋白表达情况;免疫组织化学法检测缺血侧脑NF-κB(p65)的表达;ELISA 法检测CIR 小鼠血清中HMGB1 和缺血侧脑组织中IL-1α、TNF-α的含量变化。结果:与模型组相比,BCP(248 mg/ kg)可明显改善小鼠神经功能,减少脑梗死体积,降低缺血区神经元的死亡率(P<0.01);降低血清中HMGB1 浓度、TLR4 的蛋白表达量(P<0.01),抑制炎症通路NF-κB 的激活并减少TNF-α、IL-1茁的释放(P<0.01)。结论:BCP 能够减轻CIR 诱导的小鼠脑组织损伤,其保护作用可能是通过抑制HMGB1/ TLR4/ NF-κB 介导的炎症反应。     

FSD-C10调节阿尔茨海默病双转基因小鼠炎性微环境

目的:探讨新型Rho激酶抑制剂FSD-C10对阿尔茨海默病(Alzheimer disease,AD)模型小鼠脑内炎性微环境的调节作用。方法:采用双转染人β-淀粉样蛋白前体(β-amyloid protein precursor,APP)695swe基因和人早老素1(presenilin-1,PS1)ΔE9突变基因的8月龄小鼠作为AD动物模型,随机分为模型组和FSD-C10治疗组,分别经腹腔注射生理盐水和FSD-C10(25 mg·kg~(-1)·d~(-1))持续治疗2个月,同月龄野生型小鼠作为正常对照组。应用Morris水迷宫(Morris water maze,MWM)实验检测小鼠学习和记忆能力。采用免疫组化和Western blot技术检测小鼠脑组织β-淀粉样蛋白(Aβ)、磷酸化Tau蛋白(p-Tau)、β位点APP剪切酶(BACE)、Toll样受体4(TLR-4)、磷酸化核因子κB(p-NF-κB)、诱导型一氧化氮合酶(i NOS)和精氨酸酶1(Arg-1)的表达。结果:与模型组相比,FSD-C10干预能显著改善APP/PS1双转基因小鼠学习和记忆能力,减少海马区Aβ1-42、p-Tau和BACE的表达,抑制脑内炎症信号通路TLRs/NF-κB轴TLR-4的表达和p-NF-κB的激活,减少i NOS的表达,增加Arg-1的表达。结论:FSD-C10干预能明显改善APP/PS1双转基因小鼠的学习和记忆能力,其机制可能是通过抑制TLRs/NF-κB信号通路激活,减少炎症因子的分泌及促进M1型炎性小胶质细胞向M2型抗炎小胶质细胞转化,从而改善APP/PS1双转基因小鼠脑组织炎症微环境。     

神经节苷脂对APP/PSl双转基因AD小鼠海马PI3K表达的影响

目的本实验利用APP/PS1双转基因阿尔茨海默病(AIzheimer disease,AD)小鼠模型,观察神经节苷脂对AD小鼠学习记忆能力及海马磷脂酰肌醇3激酶(phosphoinositide 3-kinases,PI3K)表达的影响。方法 APP/PS1双转基因模型小鼠20只,随机分为AD模型组(10)和神经节苷脂(GM1)组(10),再取同窝阴性小鼠10只,作为对照组。经跳台试验和水迷宫试验进行行为学测试,用免疫组化方法和Western blot方法检测各组小鼠海马PI3K的表达变化。结果与对照组相比,AD模型组小鼠的学习和记忆成绩明显降低(P0.05);相比于AD模型组小鼠,GM1组小鼠的学习和记忆成绩明显提高(P0.05)。免疫组化和Western blot结果显示,GM1组小鼠和对照组小鼠海马PI3K蛋白阳性表达的平均光密度值显著高于AD模型组,P0.05。结论 AD小鼠海马区PI3K的表达上调可能是GM1改善AD小鼠学习和记忆功能的机制之一。     

规律运动影响AD模型小鼠脑内单羧酸转运蛋白表达并改善认知功能

目的:通过对不同月龄段的AD模型小鼠进行长时间的规律有氧运动训练,来进一步阐述单羧酸转运蛋白(MCTs)在中枢的表达改变与AD模型小鼠认知功能的关系。方法:选择2、6、10月龄的AD模型小鼠(APP/PS1双转基因小鼠)和WT小鼠(C57BL/6J),给予8周的游泳训练至4、8、12月龄作为实验组。同时选择未进行游泳训练的4、8、12月龄AD模型小鼠和WT小鼠做为对照组。采用Morris水迷宫进行行为学检测(隐蔽平台实验和空间探索实验),采用Western Blot检测脑组织匀浆中MCT1、MCT2、MCT4蛋白表达水平,采用免疫组织化学染色方法观察其大脑皮层和海马区MCT1、MCT2、MCT4的表达情况。结果:(1)Morris水迷宫结果显示:在隐蔽平台实验中,经过8周游泳训练后的小鼠在前两天内较对照组相比平均逃避潜伏期和逃避路程明显降低,差异具有统计学意义(P0.05)。在空间探索实验中,实验组小鼠60 s内在目标象限停留的时间明显高于对照组小鼠(P0.05)。(2)Western Blot检测8月龄实验组和对照组小鼠脑组织匀浆MCTs的表达量,结果显示:游泳训练后实验组AD模型小鼠和WT小鼠MCTs表达量较未训练小鼠相比显著增加(P0.05)。(3)脑组织免疫组织化学染色结果显示:实验组中MCT1、MCT4在大脑皮层及海马区的表达较对照组升高(P0.05);而MCT2表达水平在两组中没有显著性差异(P0.05)。结论:长期的规律有氧运动增加了AD模型小鼠脑内不同亚型单羧酸转运蛋白的表达量,改善了中枢神经系统能量代谢状态,提高了认知功能。     

外源性NGF对APP/PS1转基因小鼠学习记忆能力的影响

目的观察外源性神经生长因子(nerve growth factor,NGF)对APP/PS1转基因小鼠学习记忆能力的影响和环磷酸腺苷反应元件结合蛋白(cAMP response element bling protein,CREB)蛋白的调节作用。方法实验分为野生组(雄性5月龄C57BL/6小鼠6只,鼻腔给予生理盐水),AD组(雄性5月龄APP/PS1小鼠6只)和AD+NGF组(雄性5月龄APP/PS1小鼠6只,鼻腔给予小鼠NGF治疗14w),应用Morris水迷宫检测小鼠的学习记忆能力变化,应用Western blot检测小鼠脑内CREB蛋白、p-CREB蛋白的表达。结果 AD+NGF组小鼠的潜伏期和找到平台前所经过的总路程均显著低于AD组小鼠,经过目标平台位置的次数明显高于AD组小鼠,游泳总路程和平均游泳速度均明显低于AD组小鼠。外源性NGF上调APP/PS1转基因小鼠脑内CREB蛋白和p-CREB蛋白的表达。结论外源性NGF改善APP/PS1转基因小鼠的学习记忆能力可能与上调CREB和p-CREB蛋白的表达相关。     

神经节苷脂对APP/PSI双转基因AD小鼠海马caspase-3和iNOS表达的影响

目的本实验利用APP/PS1双转基因阿尔茨海默病(AIzheimer disease,AD)小鼠模型,观察神经节苷脂对AD小鼠学习记忆能力及海马caspase-3与诱导型一氧化氮合酶(iNOS)表达的影响。方法 APP/PS1双转基因模型小鼠20只,随机分为AD模型组(10)和神经节苷脂(GM1)组(10),再取同窝阴性小鼠10只,作为对照组。经跳台试验和水迷宫试验进行行为学测试,用免疫组化方法Western blot方法检测各组小鼠海马caspase-3与iNOS的表达变化。结果 AD模型组小鼠的学习和记忆成绩明显低于对照组(P0.05),而GM1组小鼠明显高于AD模型组(P0.05)。AD模型组小鼠海马caspase-3与iNOS蛋白阳性表达的平均光密度值显著高于GM1组小鼠和对照组小鼠(P0.05)。结论下调AD小鼠海马区caspase-3与iNOS的表达可能是GM1改善AD小鼠学习和记忆功能的机制之一。     

β-蜕皮甾酮对APP/PS-1转基因小鼠学习记忆能力及海马Bcl-2、Bax蛋白表达的影响

目的观察β-蜕皮甾酮对APP/PS-1转基因小鼠学习记忆能力及海马Bcl-2、Bax蛋白表达的影响。方法取C57小鼠6只及APP/PS-1转基因小鼠12只,C57小鼠为对照组(Control)、APP/PS-1小鼠12只随机分为模型组(APP/PS-1)和实验组(APP/PS-1+20HE),实验组APP/PS-1转基因小鼠按14.4mg/kg的剂量灌胃β-蜕皮甾酮,每日一次,对照组及模型组小鼠灌胃等量蒸馏水,连续灌胃8周,Morris水迷宫检测小鼠学习记忆能力,尼氏染色观察各组小鼠海马组织病理学变化,免疫组化法观察海马Bcl-2和Bax蛋白表达的变化。结果模型组小鼠与对照组小鼠相比,认知能力明显下降(P<0.01),海马Bcl-2和Bax蛋白表达均增加。实验组与模型组相比,学习记忆能力明显改善(P<0.01),Bcl-2蛋白的表达增加,Bax蛋白的表达减少。结论β-蜕皮甾酮能够改善转基因小鼠的学习记忆能力,可能与促进海马Bcl-2蛋白表达和抑制Bax蛋白表达有关。     

盐酸多奈派齐对APP/PSl双转基因AD小鼠海马PI3K表达的影响美满霉素对帕金森病大鼠黑质多巴胺能神经元损伤的保护作用

目的本实验利用APP/PS1双转基因阿尔茨海默病(AIzheimer disease,AD)小鼠模型,观察盐酸多奈派齐对AD小鼠学习记忆能力及海马磷脂酰肌醇3激酶(phosphoinositide 3-kinases,PI3K)表达的影响。方法 APP/PS1双转基因模型小鼠20只,随机分为AD模型组(10)和盐酸多奈派齐组(10),再取同窝阴性小鼠10只,作为对照组。经跳台试验和水迷宫试验进行行为学测试,用免疫组化方法检测各组小鼠海马PI3K的表达变化。结果与对照组相比,AD模型组小鼠的学习和记忆成绩明显降低(<0.05);相比于AD模型组小鼠,盐酸多奈哌齐组小鼠的学习和记忆成绩明显提高(<0.05)。免疫组化检测结果证明,盐酸多奈哌齐组小鼠和对照组小鼠海马PI3K蛋白阳性表达明显增加,平均光密度值分别为(0.48±0.19)和(0.74±0.22),显著高于AD模型组(0.31±0.10,<0.05)。Western blot结果发现,盐酸多奈哌齐组小鼠和对照组小鼠海马PI3K蛋白的平均光密度值分别为(0.39±0.09)和(0.61±0.21),显著高于AD模型组(0.26±0.07,<0.05)。结论 AD小鼠海马区PI3K的表达上调可能是盐酸多奈哌齐改善AD小鼠学习和记忆功能的机制之一。     

二氢杨梅素对APP/PS1转基因小鼠学习记忆和脑内自噬的影响

目的:研究二氢杨梅素(DHM)能否通过影响自噬对阿尔茨海默病(AD)模型小鼠发挥保护作用。方法:实验动物分为3组:7月龄的APP/PS1转基因痴呆模型小鼠随机分为AD组和DHM组,同月龄野生型(WT) C57BL/6J小鼠作为WT组,每组10只。DHM处理DHM组,同浓度DMSO稀释液处理AD组和WT组。采用Morris水迷宫实验检测各组学习记忆功能;免疫组织化学(IHC)、甲硫素S(ThS)染色以及ELISA法检测β-淀粉样蛋白(Aβ)的水平; Western Blot法检测自噬相关蛋白Beclin1、LC3、p62、Cathepsin D和LAMP1的表达水平;透射电镜检测脑内自噬结构微观变化。结果:与WT组相比,AD组小鼠在水迷宫检测中平均潜伏期、探索路径增长(P 0.01),穿越平台次数减少(P 0.01);脑内Aβ斑块增加(P 0.01),出现较严重的水肿,并发现了深染的晚期自噬体; LC3-Ⅱ/Ⅰ比值降低(P 0.01),p62、LAMP1和Cathepsin D表达增加(P 0.01); DHM处理后可以改善AD小鼠的学习记忆功能(P 0.05); Aβ斑块减少(P 0.05),水肿现象减轻,并发现了自噬溶酶体的存在; Beclin1表达增加(P 0.01),p62、LAMP1和Cathepsin D表达减少(P 0.01)。结论:DHM能够通过促进Aβ的降解,以减少Aβ沉积形成的老年斑,进而改善AD小鼠的学习记忆能力。     

A combination extract of ginseng, epimedium, polygala, and tuber curcumae increases synaptophysin expression in APPV717I transgenic mice

ABSTRACT: BACKGROUND: The density of presynaptic markers of synaptic communication and plasticity, especially synaptophysin (SYP), is significantly correlated with cognitive decline and the progression of Alzheimer's disease (AD), indicating that synaptic protection is an important therapeutic strategy for AD. This study aims to investigate the synaptic protective effects of a combination of several active components extracted from the Chinese herbs ginseng, epimedium, polygala and tuber curcumae (GEPT), in the brains of APPV717I transgenic mice. METHODS: Three-month-old APPV717I mice were arbitrarily divided into 10 groups (n = 12 per group): APP groups receiving vehicle treatment for four or eight months (model groups), three dose groups of GEPT-treated mice for each treatment period, and donepezil-treated mice for each treatment period. Three-month-old C57BL/6J mice (n = 12) were also given vehicle for four or eight months (control groups). Vehicle, donepezil or GEPT were intragastrically administered. Immunohistochemistry (IHC) and Western blot analysis were used to assess protein expression in the hippocampal CA1 region and ratios of SYP to beta-actin levels in hippocampal tissue homogenate, respectively. RESULTS: Both IHC and Western blot revealed a decrease in SYP levels in the CA1 region of 7- and 11-month-old APPV717I transgenic mice compared with the control groups, whereas SYP levels were increased in donepezil- and GEPT-treated transgenic mice compared with the APP group. There was a significant difference in the levels of SYP detected by IHC between the GEPT high-dose group and the APP group after 4 months of treatment, and there were significant differences between all three GEPT groups and the APP group after 8 months of treatment. Western blotting showed that the SYP protein-beta-actin ratio was decreased in APP mice, while donepezil- and GEPT-treated transgenic mice showed increased trends in the SYP protein-beta-actin ratios. CONCLUSION: GEPT increases SYP expression and protects synapses before and after the formation of amyloid plaques in the brains of APPV717I transgenic mice.     

APP/PS1转基因小鼠海马内少突胶质细胞变化的体视学研究

目的:定量研究APP/PS1转基因小鼠海马内少突胶质细胞(OLG)的改变,探讨β-淀粉样蛋白(Aβ)对OLG的影响。方法:随机选取10月龄雄性APP/PS1转基因小鼠(AD组)和10月龄同窝生雄性野生型小鼠(WT组)各13只,运用Morris水迷宫检测各组小鼠的空间学习和记忆能力;运用体视学方法计数各组小鼠海马CA1、CA2-3和齿状回(DG)内Olig2+细胞和2',3'-环核苷酸3'-磷酸二酯酶(CNPase)阳性细胞总数;体外培养小鼠少突胶质前体细胞(MOPC),给予Aβ1-42,运用real time RT-PCR和Western Blot检测OLG相关蛋白的表达水平和含量。结果:AD小鼠逃避潜伏期显著性长于WT小鼠(P<0.05),穿台次数显著性少于WT小鼠(P<0.05);AD小鼠海马各区Olig2+细胞总数均较WT小鼠显著性增加(P<0.05),且与逃避潜伏期呈正相关,与穿台次数呈负相关,而各区CNPase+细胞总数均较WT小鼠显著性减少(P<0.05),且与逃避潜伏期呈负相关;Aβ1-42干预后MOPC的NG2及CNPase的mRNA水平显著性降低(P<0.05),Olig2含量也显著性降低(P<0.05)。结论:APP/PS1转基因小鼠海马内存在成熟OLG丢失、少突胶质细胞系异常增殖;Aβ可能引起OLG损伤和发育异常;保护海马成熟OLG以及调控OLG发育可能是防治AD的有效策略。     

利用Micro-PET显像技术分析阿尔茨海默病小鼠模型的脑糖代谢

目的 利用小动物PET（Micro-PET）影像技术18氟-脱氧葡萄糖（¹⁸F-FDG）摄取率分析阿尔茨海默病(AD)小鼠模型的脑糖代谢,探索评价治疗AD药物的影像分析技术。 方法 正常对照组、APP^swe/PSΔE9转基因模型组和安理申［2 mg/(kg&#8226;d)］治疗组小鼠共9只,自腹腔注射放射性示踪剂¹⁸F-FDG,采集脑部Micro-PET图像,通过软件IRW计算并比较各组小鼠大脑与额叶、颞叶感兴趣区（ROI）每克组织¹⁸F-FDG的摄取率。 结果 利用¹⁸F-FDG 的Micro-PET影像分析可以检测AD小鼠模型的脑糖代谢,并发现APP^swe/PSΔE9转基因小鼠的脑糖摄取明显降低,与人类AD患者表现的脑糖摄取降低一致,安理申治疗可以提升APP^swe/PSΔE9转基因小鼠的脑糖摄取。 结论 ¹⁸F-FDG Micro-PET影像分析可以用于小鼠AD模型脑葡萄糖代谢水平的检测,并可以作为阿尔茨海默病治疗药物提升脑糖代谢作用的分析技术。     

阿尔茨海默病合并2型糖尿病模型小鼠海马血管损伤与认知改变

目的 探讨2型糖尿病（T2DM）对阿尔茨海默病（AD）脑血管发育的影响,及其对AD病理发生的影响机制。 方法 40只6月龄APP/PS1转基因小鼠及同窝野生型小鼠采用高糖高脂饲料喂养6个月后,即各组小鼠12月龄时,连续4 d腹腔注射 1% 链脲佐菌素溶液,建立AD合并T2DM模型小鼠及单纯T2DM模型小鼠。设立4个组别：正常对照组、AD组、T2DM组、AD合并T2DM组,每组小鼠各10只。通过小鼠跳台实验检测小鼠学习记忆能力,墨汁灌注观察小鼠海马区血管形态,油红O染色、免疫荧光实验检测小鼠海马区各病理指标变化。 结果 与正常对照组相比,AD合并T2DM模型小鼠学习与记忆能力明显下降(P<0.05),海马区血管变细、密度明显减低(P<0.05),脂质沉积增多并出现小血管渗漏,且其海马区β-淀粉样前体蛋白裂解酶1（BACE-1）、核因子（NF)-κB与基质金属蛋白酶（MMP)-9表达增多(P<0.05)。 结论 T2DM对小鼠学习记忆功能起负作用,通过促进AD病理变化加速AD模型小鼠脑血管病变,MMP-9的异常表达也可能是引起AD血管病变的原因之一。     

Deposition of lactoferrin in fibrillar-type senile plaques in the brains of transgenic mouse models of Alzheimer's disease

We and others have previously reported that lactoferrin (LF), which acts as both an iron-binding protein and an inflammatory modulator, is strongly up-regulated in the brains of patients with Alzheimer's disease (AD). We have also studied the expression and localization of LF mRNA in the brain cortices of patients with AD. In this study, we investigated immunohistochemically the localization of LF in the brains of APP-transgenic mice, representing a model of AD. No LF immunoreactivity was detected in the brains of the wild-type mice. In the transgenic AD mice, LF deposition was detected in the brains. Double-immunofluorescence staining with antibodies directed against the amyloid-β peptide (Aβ) and LF localized the LF depositions to amyloid deposits (senile plaques) and regions of amyloid angiopathy. Senile plaque formation precedes LF deposition in AD. In the transgenic mice aged <18 months, most of senile plaques were negative for LF. LF deposits appeared weakly at about 18 months of age in these mice. Both the intensity and number of LF-positive depositions in the transgenic mice increased with age. Double-staining for LF and thioflavin-S revealed that LF accumulated in thioflavin-S-positive, fibrillar-type senile plaques. The up-regulation of LF in the brains of both AD patients and the transgenic mouse model of AD provides evidence of an important role for LF in AD-affected brain tissues.     

淫黄葛复合剂对阿尔茨海默病小鼠行为学和海马解聚素金属蛋白酶10表达的影响

目的 探讨淫羊藿、黄芪、葛根有效组分复方对阿尔茨海默病（AD）模型小鼠行为学和海马CA3区解聚素金属蛋白酶10（ADAM10）表达的影响。方法 10月的雄性APPswe/PS1dE9双转基因模型小鼠30只随机分为复方组、模型组和去铁斯诺(DFX)组,10月龄的雄性C57BL/6 J小鼠10只作为正常对照组。用药结束后,采用Morris水迷宫检测各组小鼠学习记忆能力,并于水迷宫后取出小鼠的脑组织,应用免疫荧光、Real-time PCR和Western blotting方法检测各组小鼠海马CA3区ADAM10的表达。结果 水迷宫实验结果显示,与正常对照组小鼠相比,模型组小鼠的逃避潜伏期、游泳距离和游泳时间均明显延长(P＜0.05),穿越平台区域次数和平台区域停留时间明显减少(P＜0.05),首次穿越平台的逃避潜伏期明显延长(P＜0.05);与模型组小鼠相比,复方组和DFX组逃避潜伏期、游泳距离和游泳时间明显缩短(P＜0.05),穿越平台区域次数和平台区域停留时间明显增多(P＜0.05),首次穿越平台的逃避潜伏期明显缩短;复方组和DFX组相比,逃避潜伏期、游泳距离和游泳时间及跨台次数差异无显著性 (P＞0.05),穿越平台区域次数、平台区域停留时间和首次穿越平台的逃避潜伏期差异无显著性 (P＞0.05)。与正常对照组小鼠相比,模型组小鼠海马CA3区ADAM10的表达增高(P＜0.05);与模型组相比,复方组和DFX组小鼠海马CA3区DAM10的表达降低(P＜0.05);复方组和DFX组相比,ADAM10表达水平差异无显著性 (P＞0.05)。结论 应用淫羊藿、黄芪、葛根有效组分复方可以改善APPswe/PS1dE9双转基因AD模型小鼠的学习记忆能力,其机制可能与下调ADAM10的表达减少神经元的损伤和死亡有关。     

APPSWE Tg2576小鼠脑屏障结构

目的探讨小鼠的血脑屏障(BBB)及血脑脊液屏障(BCSFB)的基本结构及其在阿尔茨海默病(AD)发生、发展过程中结构、功能及及其超微结构的改变。方法实验用动物采用APPSWE Tg2576鼠,分为APPSWE转基因阳性鼠(模型组)和同窝生野生型小鼠(对照组),每组各20只。饲养16个月后进行全身灌流固定,开颅切取侧脑室室壁及其脉络丛组织。采用免疫荧光及透射电子显微镜技术观察BBB及BCSFB的超微结构,从而观察AD模型脑屏障的改变。结果 AD模型组与对照组相比较,血管密度明显降低; AD小鼠脑屏障正常结构受到损害,主要是脑血管内皮细胞(或脉络丛内皮细胞)之间的连接及其细胞器受损,脉络丛超微结构也出现明显变化,主要表现为细胞间隙增宽,细胞之间的黏附连接等连接结构也有部分碰坏,胞质内出现较多的囊泡状结构等。结论和正常鼠相比,AD鼠脑屏障受到一定的损害,可能致使脑屏障的转运机制出现相应的改变并影响脑内β-淀粉样蛋白(Aβ)的清除,脑屏障中存在的稳态机制,如其分泌物和受体介导的信号传导也可能出现改变,这些因素可能共同参与了AD的形成和进展。     

Curcumin Ameliorates Memory Deficits by Enhancing Lactate Content and MCT2 Expression in APP/PS1 Transgenic Mouse Model of Alzheimer's Disease

Curcumin is a natural product with several anti-Alzheimer's disease (AD) neuroprotective properties. This study aimed to investigate the effects of curcumin on memory deficits, lactate content, and monocarboxylate transporter 2 (MCT2) in APP/PS1 mouse model of AD. APP/PS1 transgenic mice and wild-type (WT) C57BL/6J mice were used in the present study. Spatial learning and memory of the mice was detected using Morris water-maze test. Cerebral cortex and hippocampus lactate contents were detected using lactate assay. MCT2 expression in the cerebral cortex and hippocampus was examined by immunohistochemistry and Western blotting. Results showed that spatial learning and memory deficits were improved in curcumin-treated APP/PS1 mouse group compared with those in APP/PS1 mice group. Brain lactate content and MCT2 protein level were increased in curcumin-treated APP/PS1 mice than in APP/PS1 mice. In summary, our findings indicate that curcumin could ameliorate memory impairments in APP/PS1 mouse model of AD. This phenomenon may be at least partially due to its improving effect on the lactate content and MCT2 protein expression in the brain. Anat Rec, 302:332–338, 2019. © 2018 Wiley Periodicals, Inc.     

Beneficial effect of ovocystatin on the cognitive decline in APP/PS1 transgenic mice

PurposeCystatin C plays an important role in the course of neurodegenerative diseases and has a beneficial effect through inhibiting cysteine proteases and amyloid-β aggregation. It also induces proliferation and autophagy. Cystatin isolated from chicken egg white, called ovocystatin, has been widely used in the medical and pharmaceutical research due to its structural and biological similarities to human cystatin C. The aim of this study was to assess the effect of administering ovocystatin on the development of dementia-specific cognitive deficits in APP/PS1 transgenic mice.Materials/methodsThe study was conducted on transgenic B6C3-Tg(APPswe,PSEN1dE9)85Dbo/Mmjax mice. Ovocystatin was administered to four-month-old transgenic (AD) and wild type (NCAR) mice in drinking water for 24 weeks (at a dose of 40 and 4 μg/ mouse). The locomotor activity and cognitive functions were determined using an actimeter and the Morris water maze test, respectively.ResultsThe results of the study indicate that ovocystatin has a beneficial effect on the cognitive functions in APP/PS1 transgenic mice. The strongest effects of ovocystatin were found in the group of AD mice, where ovocystatin was administered in drinking water at a dose of 40 μg/mouse (p < 0.05). Mice from the AD group swam statistically significantly further in the target zone during the trial in the Morris water maze compared to the AD (vehiculum) group (p < 0.05).ConclusionsThe obtained results encourage further research into the protective effect, which may be used as an adjuvant in the treatment of deteriorating cognitive functions.