美满霉素抑制血管性认知功能损伤大鼠海马星型胶质细胞激活和神经炎症(英文)

目的观察美满霉素(minocycline)对血管性认知功能损伤大鼠海马组织GFAP、COX-2、NF-κB、IL-1β和TNF-α表达的影响,探讨美满霉素对血管性认知功能损伤脑保护作用的机制。方法Wistar大鼠随机分为假手术组(S组)、血管性认知功能损伤模型组(M组)和美满霉素治疗组(MT组)。免疫组织化学法检测大鼠海马组织COX-2和NF-κB的表达,蛋白质印迹和免疫组织化学法检测大鼠海马组织GFAP的表达,ELISA法检测大鼠海马组织IL-1β和TNF-α的表达。结果MT 组 GFAP、COX-2、NF-κB、IL-1β和 TNF-α表达较 M 组均降低(P<0.01) ;MT 和 M 组GFAP、COX-2、NF-κB、IL-1β和 TNF-α表达均显著高于 S 组(P<0.01)。结论美满霉素能降低血管性认知功能损伤大鼠海马组织中GFAP、COX-2、NF-κB、IL-1β和TNF-α的表达,抑制血管性认知功能损伤大鼠海马星型胶质细胞活化和神经炎症,发挥脑保护作用。     

血管性痴呆大鼠认知功能及nNOS的表达

目的 探讨血管性痴呆(VD)大鼠认知功能、海马神经元结构及nNOS的表达.方法 采用双侧颈总动脉结扎法制备慢性前脑缺血动物模型,40只老龄大鼠随机分为假手术组(S)、模型组(M).应用水迷宫、透射电镜及免疫组化方法对2组大鼠学习记忆、神经元结构、nNOS表达进行观察.结果 与假手术组比较,大鼠水迷宫学习记忆能力在造模2个月后差异有统计学意义(P＜0.05),大鼠海马神经元在造模后变性水肿明显,大鼠海马及颞叶皮层nNOS在造模2个月后表达增加 (P＜0.05).结论 海马及颞叶皮层nNOS表达增加,神经元变性,可能导致血管性痴呆大鼠学习记忆障碍.     

神经元型一氧化氮合酶在血管性痴呆大鼠海马中的表达

目的 探讨神经元型一氧化氮合酶(nNOS)在血管性痴呆(VD)大鼠海马中的表达。方法 将60只大鼠随机分为：对照组、VD12h组、VD1d组、VD3d组、VD7d组。采用反复夹闭双侧颈总动脉方法建立VD大鼠模型，用HE染色观察各组大鼠海马CA1区神经元的数目；应用免疫组化染色和Western印迹方法检测nNOS在大鼠海马中的表达。结果 VD12h组、VD1d组、VD3d组、VD7d组大鼠海马CA1区神经元数均明显下降。nNOS在对照组大鼠海马CA1区中弱表达．在VD12h组表达增强．VD1d组进一步增强，VD3d和7d组表达逐渐减弱。结论 nNOS可能参与缺血早期海马神经元的损害，是VD的发病机制之一。     

丁苯酞对血管性痴呆大鼠认知功能、海马神经元结构及nNOS的影响

目的研究丁苯酞对血管性痴呆（VD）大鼠认知功能、海马神经元结构、及神经元型一氧化氮合酶（nNOS）的影响。方法采用结扎双侧颈总动脉方法制备慢性前脑缺血动物模型,100只老龄大鼠随机分5组,应用水迷宫、透射电镜及免疫组化方法对各组大鼠学习记忆、神经元结构、nNOS表达进行观察。结果与假手术组比较,大鼠学习记忆能力在造模后差异有显著性意义（P〈0.05）;大鼠海马区神经元在造模后变性水肿明显,与模型组比较,丁苯酞不同剂量治疗1月后,大鼠学习记忆能力明显改善（P〈0.05）,神经元变性水肿减轻,nNOS阳性神经元表达减少（P〈0.05）。结论丁苯酞能显著改善VD大鼠学习记忆能力;减轻神经元变性水肿;抑制nNOS阳性神经元表达。     

米诺环素改善血管性痴呆大鼠认知功能障碍的机制研究

目的探索米诺环素是否在血管性痴呆导致的认知功能损害发生发展中发挥一定的神经保护作用,并进一步分析参与其中的相关分子机制。 方法SD大鼠随机分为假手术组、模型组和米诺环素治疗组。结扎双侧颈总动脉建立大鼠血管性痴呆模型,术后腹腔注射米诺环素（25,50 mg/kg）,28 d后进行水迷宫行为学实验检测认知变化,HE染色和Western blotting分析大鼠海马神经细胞凋亡的相关机制。 结果（1）水迷宫认知功能测试显示,米诺环素能够显著缩短血管性痴呆大鼠寻找平台的潜伏期,并且明显延长在目标象限的停留时间,P<0.05为差异具有统计学意义。（2）HE染色显示米诺环素能够显著减轻模型组大鼠海马神经细胞损伤。（3）米诺环素治疗组含半胱氨酸的天冬氨酸蛋白水解酶-3（Caspase-3）蛋白表达水平及Bax/Bcl-2比值较模型组明显下降,P<0.05为差异具有统计学意义。（4）与模型组相比,米诺环素组磷脂酰肌醇3-激酶（PI3K）及磷酸化蛋白激酶B（p-AKT）蛋白表达水平明显升高,磷酸化糖原合酶激酶-3β（p-GSK-3β）蛋白表达却显著下降,P<0.05为差异具有统计学意义。 结论米诺环素通过激活PI3K/AKT信号通路,抑制该通路下游靶分子GSK-3β活性,减少海马神经细胞凋亡的发生,在神经细胞保护和改善认知功能障碍中发挥重要作用。     

从血管性痴呆到血管性认知功能损害

本文通过回顾血管性痴呆的提出及争议，引出血管性认知功能损害提出的背景及其必要性，阐述了其诊断标准目前存在的问题及新近的研究进展，旨在通过比较血管性痴呆到血管性认知功能损害定义的演变说明血管性认知功能损害这一定义的重要性，指出寻找血管性认知功能损害特异性的神经心理学表现、影像学特点、生物学标记以及病理学特点将是今后。     

银杏叶制剂改善血管性痴呆患者认知功能的研究

目的探讨银杏制剂对血管性痴呆疾病防治作用。方法试验分为对照组及银杏叶制剂治疗组,各组治疗前及治疗后1、3、6个月分别进行MMSE评分及NIHSS评分。结果治疗后1个月NIHSS评分较对照组明显降低(P<0.05),3、6个月NIHSS评分较治疗后1个月银杏制剂治疗组无明显改变(P>0.05);治疗后1、3个月MMSE评分较对照组无明显改变(P>0.05),6个月后MMSE评分明显降低,与对照组比较差异显著(P<0.05)。结论银杏叶制剂具有改善血管性痴呆患者认知功能的作用。     

丁苯酞对血管性痴呆大鼠nNOS及SS的影响

目的研究丁苯酞对血管性痴呆(vascular dementia,VD)大鼠神经元型一氧化氮合酶(nNOS)及生长抑素(SS)的影响。方法采用结扎双侧颈总动脉方法制备慢性前脑缺血动物模型,100只老龄大鼠随机分5组,应用免疫组化方法对各组大鼠nNOS及SS表达进行检测。结果丁苯酞不同剂量治疗1个月后,nNOS阳性神经元表达减少(P<0.05),SS阳性细胞表达增加(P<0.05)。结论丁苯酞可抑制nNOS阳性神经元表达,增加SS阳性细胞的表达。     

辛伐他汀改善血管性痴呆患者认知功能障碍效果的初步研究

目的初步探讨辛伐他汀对血管性痴呆患者认知功能障碍的改善效果。方法本实验选取2011-12—2012-02到我院进行治疗的血管性痴呆患者60例为研究对象,按治疗方法分为对照组30例(常规药物治疗)和观察组30例(常规药物联合辛伐他汀治疗),比较2组患者的日常生活能力及认知功能改善情况。结果比较2组患者治疗前ADL评分情况和MMSE评分情况,观察组与对照组均无明显区别,差异无统计学意义(P>0.05);2组患者治疗后语言表述、语言理解、阅读理解、言语表达、时间定向、注意力、画图、短程记忆和计算能力等方面的MMSE评分情况均有不同程度提高,组内比较,2组患者治疗前后MMSE评分情况,差别具有统计学意义(P<0.05);2组患者治疗后较治疗前ADL评分均明显改善,治疗前后比较,差异均有统计学意义(P<0.05);而观察组患者治疗后MMSE评分情况和ADL评分情况则明显优于对照组,差异有统计学意义(P<0.05)。结论血管性痴呆患者在常规治疗基础上加服辛伐他汀可明显提高患者的日常生活能力和认知功能,效果显著,是一种简便有效的治疗方法,值得临床推广和使用。     

Minocycline attenuates white matter damage in a rat model of chronic cerebral hypoperfusion

White matter lesions are thought to result from chronic cerebral ischemia and constitute a core pathology of subcortical vascular dementia. This rarefaction has been known to be associated with microglial activation. We investigated whether minocycline, a microglial inhibitor, attenuates the white matter damage induced by chronic cerebral hypoperfusion that is used as a model of vascular dementia. Male Wistar rats were subjected to bilateral, permanent occlusion of the common carotid arteries (BCCAO) to induce chronic cerebral hypoperfusion. Minocycline or saline was injected daily for 2 weeks after BCCAO. In the corpus callosum and the optic tract, white matter damage observed with Klüver-Barrera staining was significantly attenuated in the minocycline-treated group compared to saline-treated controls. In control rats, immunoreactivities of major basic protein (MBP), Ox-42 as a microglial marker, and matrix metalloproteinase (MMP)-2 were increased in the corpus callosum. Minocycline significantly reduced these changes. Co-expression of Ox-42 and MMP-2 was confirmed by double immunofluorescence histochemistry. Our results suggest that chronic treatment with minocycline could be protective against at least some ischemic white matter damage, and its mechanism may be related to suppressing microglial activation.     

Prenatal stress causes gender-dependent neuronal loss and oxidative stress in rat hippocampus

Our purpose was to investigate the effects of prenatal stress on neuronal changes in the hippocampus and the possible involvement of oxidative stress in female and male rats. Female and male offspring (1-month-old), whose dams were restrained in middle or later pregnant stage (MS or LS), were studied to observe changes in the number of hippocampal neurons and the expression of neuronal nitric oxide synthase (nNOS) in the hippocampus. Both MS and LS induced an increase in the number of nNOS-positive expression in female and male offspring in the hippocampus; however, both MS and LS caused a significant decrease in the number of hippocampal neurons in the female, but not in the male offspring. In addition, significant increases in calcium content and oxidant generation were induced by LS in the hippocampal CA3 region in female rats. These data suggest that prenatal stress can cause oxidative stress and consequent damage to neurons, leading to neuronal loss in the brain of offspring during development.     

慢性脑低灌注大鼠海马Arc低表达与其认知功能障碍的相关性研究

目的 探讨慢性脑低灌注大鼠海马活性调节的细胞骨架相关蛋白(activity-regulated cytoskeletal-associated protein,Arc)的低表达与其认知功能障碍的相关性。方法 大鼠慢性脑低灌注模型使用持久性双颈总动脉结扎术(2-vessel occlusion,2-VO); 大鼠随机分成假手术组和2-VO组,每组各6只。术后第8周行Morris水迷宫评价其认知功能; 实时定量聚合酶链式反应(Real time quantitative polymerase chain reaction,RT-qPCR)及蛋白免疫印迹法检测大鼠海马Arc mRNA及蛋白表达水平。结果(1)2-VO组大鼠第2～5 d的逃逸潜伏期比假手术组明显延长(P<0.01)及其在原平台区域游泳时间明显比假手术组短(P<0.01);(2)2-VO组大鼠海马Arc mRNA水平及免疫反应条带相对灰度值分别比假手术组明显降低(P均<0.01);(3)空间探索实验中2-VO大鼠在原平台区域游泳时间与海马Arc免疫反应条带相对灰度值呈正相关(r=0.7085,P<0.05)。结论 慢性脑低灌注大鼠的认知功能障碍可能与海马Arc的低表达相关。     

Changes in oxidative stress,iNOS activity and neutrophil infiltration in severe transient focal cerebral ischemia in rats

Oxidative stress, inducible nitric oxide synthase (iNOS) and neutrophils all contribute to post-ischemic brain damage. This study has determined the time courses of these three phenomena after ischemia in parallel with histological and functional outcomes. Ischemia was produced in rats by occluding the left middle cerebral artery and both common carotid arteries for 20 min. Regional cerebral blood flow (rCBF) rapidly decreased to 20% of its preischemic value during occlusion and stabilized at 60% following reperfusion. The striatal infarction was maximal 15 h after reperfusion (50+/-3 mm(3)), whereas the cortical infarction reached its maximum at 48 h (183+/-10 mm(3)). This drastic decrease in rCBF followed by incomplete reperfusion and massive infarction is, thus, extremely severe. The cortical infarction was strongly correlated with the neurologic deficit and loss of body weight. Oxidative stress, evaluated by the decrease in glutathione concentrations, appeared in the striatum at 6 h after reperfusion and in the cortex at 15 h. Calcium-independent NOS activity, considered as inducible NOS activity, was significantly enhanced at 24 h in the striatum and at 48 h in the cortex. Myeloperoxidase activity, a marker of neutrophil infiltration, was significantly increased at 48 h in both the striatum and cortex. These time courses show that the delayed iNOS activity and neutrophil infiltration that occur after the maturation of infarction in severe ischemia may not contribute to ischemic brain damage. By contrast, early oxidative stress may well be implicated in cerebral injury.     

Reversible short-term and delayed long-term cognitive impairment induced by chronic mild cerebral hypoperfusion in rats

Chronic cerebral hypoperfusion induced by aging in combination with vascular disorder potentially contributes to the development of vascular dementia. This study aimed to investigate the age-related changes in spatial performances in chronic mild cerebral hypoperfusion induced by permanent right common carotid artery occlusion (rCCAO) in rats. Four-month-old male Sprague–Dawley rats (n = 20) were randomly assigned into sham and rCCAO groups. Spatial performances of young adult rats (age 4–8 months) were evaluated repeatedly by the radial arm water maze at 6 days, and 1, 2 and 4 months after surgery. The spatial performance was re-assessed by the Morris water maze when the rats were 18 months old. The present results revealed that the rCCAO rats developed progressive deficit in spatial learning and memory, starting from day 6 and significant deficit was found at 2 months after rCCAO (p < 0.05). However, the spatial performance of the rCCAO rats was recovered at 4 months after surgery. Testing of the cognitive flexibility of the aged rCCAO rats (18 months old), indicated that the learning flexibility of the aged rCCAO rats was significantly impaired. This deficit was found in parallel with pronounced white matter damage in the corpus callosum and internal capsule and significant cell death in the dorsal hippocampus. Our results suggested that vascular risk insult in young adult rats resulted in spatial learning deficit which could be completely compensated later on. However, such previous vascular risk could be exacerbated by advancing age and subsequently lead to a deficit in cognitive flexibility with white matter damage and significant neuronal death in the dorsal hippocampus.