阿托伐他汀可增强血管性痴呆模型中大鼠海马CA1区发动蛋白1的表达

The current study examined a rat model of vascular dementia.The model rats exhibited obvious morphological and ultrastructural changes in neurons in the brain,and significantly reduced dynamin 1 expression in hippocampal CA1 region along with decreased learning and memory performance.Following atorvastatin treatment,the morphology and ultrastructure of cells in the model rat brain were significantly improved,dynamin 1 expression in hippocampal CA1 region was significantly enhanced,and learning and memory ability was significantly improved.The results demonstrated that impaired learning and memory abilities in vascular dementia model rats were closely correlated with decreased dynamin 1 expression.These findings indicate that atorvastatin can protect model rats against cognitive impairment by increasing dynamin 1 expression.     

成纤维细胞生长因子2和成纤维细胞生长因子受体1蛋白在慢性应激抑郁大鼠海马中的表达

There is evidence that the expression of members of the fibroblast growth factor(FGF) protein family is altered in post-mortem brains of humans suffering from major depressive disorder.The present study examined whether the expression of fibroblast growth factor-2(FGF2) and fibroblast growth factor receptor-1(FGFR1) protein is altered following chronic stress in an animal model.Rats were exposed to 35 days of chronic unpredictable mild stress,and then tested using open-field and sucrose consumption tests.Compared with the control group,rats in the chronic stress group exhibited obvious depressive-like behaviors,including anhedonia,anxiety and decreased mobility.The results of western blot analysis and immunohistochemical analysis revealed a downregulation of the expression of FGF2 and FGFR1 in the hippocampus of rats,particularly in the CA1,CA3 and dentate gyrus.This decreased expression is in accord with the results of post-mortem studies in humans with major depressive disorder.These findings suggest that FGF2 and FGFR1 proteins participate in the pathophysiology of depressive-like behavior,and may play an important role in the mechanism of chronic stress-induced depression.     

亚低温对大鼠弥漫性脑损伤后海马 CA1区Apaf-1蛋白表达的影响

弥漫性脑损伤(diffuse brain injury)是闭合性脑外伤的一种,致残率及死亡率均较高[1-2].目前,国内外学者对亚低温治疗脑外伤进行了相关的基础和临床研究,但关于亚低温与神经细胞凋亡之间的关系研究相对较少.本研究通过探讨亚低温对大鼠弥漫性脑损伤后海马CA1区凋亡蛋白酶激活因子-1(apoptotic protease activating factor-1,Apaf-1)蛋白表达及学习记忆功能的影响,旨在为临床治疗颅脑创伤患者提供科学依据.     

亚低温对大鼠弥漫性脑损伤后海马CA1区Apaf-1蛋白表达和学习记忆功能的影响

目的 探讨亚低温对大鼠弥漫性脑损伤(DBI)后海马CA1区Apaf-1蛋白表达及大鼠学习记忆功能的影响.方法 选择雄性Wistar大鼠48只,按照完全随机数字表法分为正常组、假手术组、脑损伤组和亚低温组,每组12只.正常组不做任何处理;假手术组仅给予麻醉及头皮切开、缝合,但不致伤;脑损伤组和亚低温组根据Marmarou方法制作DBI模型,亚低温组大鼠损伤后用冰毯及冰袋物理降温,使大鼠肛温在15 min内控制至30.0～31.0℃,维持2 h.14 d后比较各组大鼠Morris水迷宫实验成绩,同时比较各组大鼠海马CA1区Apaf-1蛋白的表达.结果 正常组、假手术组、脑损伤组和亚低温组大鼠搜索安全岛的次数分别为(10.1±1.9)次、(10.3±1.8)次、(3.8±2.3)次和(6.9±1.1)次,差异有统计学意义(P<0.05).脑损伤组及亚低温组海马CA1区Apaf-1蛋白含量高于正常组及假手术组,其中脑损伤组Apaf-1蛋白含量明显高于亚低温组,差异均有统计学意义(P<0.05).结论 亚低温可能通过抑制神经细胞凋亡对脑组织产生保护作用,从而改善大鼠脑损伤后学习记忆障碍.

Abstract：

Objective To investigate the influence of mild hypothermia on the apoptotic protease activating factor-1 (Apaf-1) protein expression in the hippocampal CA1 area and learning and memory functions of rats after diffuse brain injury (DBI). Methods Forty-eight male Wistar rats were equally randomized into normal group, sham-operated group, brain injury group and mild hypothermia treatment group (n=12). Rats in the normal group did not receive any treatment; rats in the sham-operated group only received anesthesia, and incision and suture of scalp; rats in the brain injury group and mild hypothermia treatment group were induced the DBI models according to Marmarou method; and rats in the mild hypothermia treatment group were performed hypothermia with ice blanket and ice bag to control the rectal temperature within 30.0-31.0 ℃ for 2 h. After DBI for 2 weeks, the times of searching refuge platform and the protein expression of Apaf-1 were compared among the 4 groups. Results The times of searching refuge platform in the normal group, sham operated group, brain injury group and mild hypothermia treatment group were (10.1 ±1.9), (10.3±1.8), (3.8±2.3) and (6.9±1.1), respectively,with significant differences between each 2 groups (P<0.05). The protein expression of Apaf-1 in the brain injury group and mild hypothermia treatment group was obviously higher than that in the other groups (P<0.05), and significantly lower protein expression of Apaf-1 in the mild hypothermia rats was noted as compared with that in the brain injury rats (P<0.05). Conclusion Mild hypothermia might play a protective role by inhibiting neuronal apoptosis for rats with DBI through the Apaf-1 pathway,which can improve learning and memory abilities.     

亚低温对大鼠弥漫性脑损伤后海马CA3区HSP70表达及细胞凋亡的影响

目的 观察亚低温对大鼠弥漫性脑损伤(DBI)后海马CA3区HSP70在蛋白质和mRNA水平的表达及细胞凋亡上的影响,探讨亚低温脑保护分子生物机制。方法 将大鼠随机分成空白对照、假手术、单纯DBI和DBI后亚低温治疗四组,按Marmarou氏方法制作大鼠DBI模型,采用免疫组化法、逆转录聚合酶链反应(RT-PCR)及流式细胞仪(FCM),分别观察各组动物脑海马CA3区HSP70在蛋白质和mRNA水平的表达及细胞凋亡率。结果 与对照组相比,大鼠DBI后海马CA3区HSP70表达水平及细胞凋亡率均升高(P<0.05);亚低温治疗后,大鼠脑海马CA3区HSP70表达水平较单纯DBI组显著增高(P<0.01),而细胞凋亡率则明显降低(P<0.05)。结论 亚低温对创伤性脑损伤的脑保护机制可能与促进HSP70表达,并减少神经细胞凋亡有关。     

亚低温对大鼠创伤性脑损伤后海马CA3区细胞凋亡及其相关蛋白表达的影响

本研究采用流式细胞仪 (flowcytometer ,FCM )及免疫组化法 ,分别观察亚低温对大鼠创伤性脑损伤 (TBI)后脑海马CA3区细胞凋亡率及Bcl 2、Bax和Caspase 3蛋白表达的影响 ,探讨亚低温抗细胞凋亡的脑保护机制。1　材料和方法1 1　研究对象 :雄性SD大鼠 4 8只 ,体重 350～ 375g ,随机分成空白对照、假手术、单纯脑损伤及脑损伤后亚低温治疗 4组 ,每组1 2只 ,6只用于检测细胞凋亡率 ,另 6只用来观察Bcl 2、Bax及Caspase 3蛋白表达。空白对照组不作任何处理 ,假手术组除了不给予头部打击外 ,其余操作同单纯脑损伤组 ,亚低温治疗组于伤后立…     

亚低温对大鼠脑创伤后海马区凋亡相关蛋白表达的影响

目的观察亚低温对大鼠创伤性脑损伤(TBI)后海马CA3区细胞凋亡及相关蛋白Bcl-2、Bax及Caspase-3表达的影响,探讨亚低温脑保护的分子生物学机制.方法将大鼠随机分成假手术、单纯脑损伤和脑损伤后亚低温治疗3组,应用改良Marmarou方法制作大鼠TBI模型,分别用流式细胞仪(FCM)和免疫组化法检测各组动物脑海马CA3区细胞凋亡率和Bcl-2、Bax及Caspase-3蛋白的表达.结果与假手术组相比,大鼠TBI后海马CA3区细胞凋亡率及Caspase-3表达增高(P<0.05),Bcl-2/Bax表达比下降(P<0.05).亚低温治疗后,大鼠脑海马CA3区细胞凋亡率及Caspase-3表达较单纯脑损伤组降低(P<0.05),而Bcl-2/Bax表达比升高(P<0.05).结论亚低温对TBI的脑保护作用机制可能与干预伤后凋亡相关基因表达并减少神经细胞凋亡有关.     

延迟亚低温治疗对大鼠永久性大脑中动脉阻塞后凋亡相关蛋白表达的影响

目的 研究延迟亚低温治疗对大鼠永久性脑缺血的神经保护作用以及作用机制.方法 线栓法制备永久性大脑中动脉阻塞(pMCAO)模型,随机分为3组,每组10只.亚低温治疗组(HT组)分为HT 2h组和HT 6h组,前者在pMCAO后2h给予亚低温(33±0.5℃)治疗22h,后者在pMCAO后6h给予亚低温(33±0.5℃)治疗18h.缺血对照组(NT组)在pMCAO后放置于室温(25℃).制备pMCAO模型过程中,应用激光多普勒血流监测仪监测局部大脑中动脉供血区脑血流量.持续监测直肠温度.各组大鼠均于pMCAO后24h灌注取脑制备冰冻切片,进行TUNEL染色以及Bcl-2、Bax、Caspase-3免疫组织化学染色.结果 NT组有3只大鼠死亡,亚低温治疗组无大鼠死亡.与NT组比较,HT组皮层缺血半暗带区域凋亡细胞减少,Bcl-2蛋白表达增多,Bax蛋白表达减少,Bcl-2/Bax比值升高,Caspase-3蛋白表达显著减少(P<0.05).与HT 6h组比较,HT 2h组皮层缺血半暗带区域凋亡细胞减少(P<0.05),但Bcl-2、Bax、Caspase-3蛋白表达以及Bcl-2/Bax比值均无显著性差异(P>0.05).结论 永久性脑缺血后延迟6h给予亚低温治疗18h仍然可以减少缺血后神经细胞凋亡.延迟亚低温治疗通过抑制Bcl-2基因家族蛋白介导的线粒体依赖性Caspase激活途径,抑制Caspase介导的细胞凋亡途径,从而发挥神经保护的作用.在脑缺血的治疗过程中,要尽早给予亚低温治疗,以保护更多的神经元和更好地促进神经功能的恢复.     

急性低氧条件下复氧后大鼠脑HIF-1α蛋白的表达与药物干预研究

目的 观察大鼠脑缺氧状态下HIF-1α蛋白的表达规律及低氧状态下人参皂甙Rd干预对其影响并探讨机理。方法 将成年Wistar大鼠随机分为常氧对照组、急性低氧对照组、低氧预处理干预组、人参皂甙Rd干预组，分别观察各组大鼠海马锥体细胞层神经元形态的变化及HIF-1α蛋白的表达规律。结果 在缺氧后复氧即刻，我们可以发现HIF-1α蛋白的少量表达，主要存在于海马细胞，多在细胞质中表达；随着时间的推移，在复氧后4小时，HIF-1α表达逐渐达高峰，至9小时HIF-1α表达又明显减少。低氧预处理干预组及人参皂甙Rd干预组的实验结果发现HIF-1α表达较非干预组减少，与非干预组各时间点相比，均有统计学意义（P=0.009＜0.05）。两个干预组之间比较无统计学差异(P＞0.05)。结论 急性低氧可以促使HIF-1α在大鼠海马神经细胞的表达，具有时间依赖性；同时，低氧预处理干预及人参皂甙Rd干预均可促使大鼠脑组织HIF-1α表达减少，可能对急性缺氧性脑损伤产生保护作用，抑制氧自由基的产生及调节钙离子内流可能是低氧预处理及人参皂甙Rd的作用途径之一，其具体机理有待进一步阐明。     

轻度低温治疗27例弥漫性轴索损伤病人的临床疗效

目的 探讨早期使用轻度低温治疗中、重型弥漫性轴索损伤(DAI)病人的疗效。方法 对我科收治的27例中、重型弥漫性轴索损伤病人，早期使用冰毯机降温至轻度低温(35℃～35．5℃)脑保护，加用冬眠Ⅰ号等药物配合治疗，但不使用呼吸机和肌松剂。结果 17例存活，10例死亡。存活病人中恢复良好11例，重残6例。结论 该方法适合于基层医院或条件相对不足的医疗单位，仍能取得良好疗效。     

垂体腺瘤凋亡蛋白酶活化因子-1基因启动子区甲基化与其mRNA表达

目的研究凋亡蛋白酶活化因子-1（apoptotic protease activating factor-1,APAF-1）基因启动子区甲基化状态及其mRNA表达与临床特征的关系。方法用甲基化特异性聚合酶链反应（MS—PCR）和逆转录聚合酶链反应（RT—PCR）技术,检测32例垂体腺瘤组织和6例正常垂体组织APAnJ启动子区甲基化状态与其mRNA表达水平,分析APAF-1基因甲基化和mRNA表达与临床特征的关系。结果正常垂体组织APAF-1基因mRNA表达未见明显下降或升高,启动子区未发生甲基化。垂体腺瘤组织APAF-1基因mRNA表达下调率为56.3％（18例）,其表达显著性低于正常垂体组织（P=0．021,P〈0．05）。APAF-1基因启动子区甲基化率为43．8％（14例）。APAF—1 mRNA表达下调的垂体腺瘤组织中启动子甲基化率显著高于无表达下调者（P=O．009）。侵袭性和非侵袭性垂体腺瘤之间APAF-1 基因mRNA表达及其甲基化率均无显著差异。结论垂体腺瘤组织APAF-1基因mRNA表达下调,APAF-1启动子区甲基化和其mRNA表达下调有关。在垂体腺瘤中,APAF-1基因启动子区甲基化可能是一个重要的分子改变,其在垂体腺瘤发生、发展中有重要意义。     

不同时间局部亚低温治疗弥漫性轴索损伤的预后分析

目的 探讨弥漫性轴索损伤(DAD后不同时间点行亚低温治疗与患者预后的关系.方法 回顾性分析桂林市全州县人民医院院神经外科自2006年1月至2010年1月收治的48例弥漫性轴索损伤患者的临床资料,按照伤后有无在常规治疗的基础上加用局部亚低温辅助治疗分为亚低温治疗组(n=23)和对照组(n=25),前者按治疗时间又分为伤后8h内亚低温治疗组(n=9)和伤后8 h后亚低温治疗组(n=14),治疗6个月后对患者行GOS评定,分析患者的预后.结果 3组患者年龄、性别比例、治疗前颅内压、GCS评分方面差异均无统计学意义(P>0.05);分别接受不同治疗后3组患者预后差异有统计学意义(x2-6.671,P=0.036),由平均秩次判断,预后最好的为伤后8 h内亚低温治疗组,其次为伤后8 h后亚低温治疗组和对照组.结论 弥漫性轴索损伤患者伤后早期(8 h内)进行局部亚低温辅助治疗有助于脑功能的恢复,提高预后.

Abstract：

Objective To investigate the effect of local mild hypothermia at different times on the prognosis of patients with diffuse axonal injury (DAI). Methods Forty-eight patients with DAI,admitted to our hospital from January 2006 to January 2010, were chosen, and their general clinical data were retrospectively analyzed.According to whether adjuvant treatment with mild hypothermia was performed besides conventional therapy, patients were divided into mild hypothermia (n=23) and control group (n=25). The former group was sub-divided into group A (giving mild hypothermia treatment within 8 h of injury, n=9) and group B (giving mild hypothermia treatment over 8 h of injury, n=14). Patients were assessed with Glasgow outcome scale (GOS) and the prognosis of these patients was analyzed 6 months after treatment. Results No significant differences on age, gender ratio, intracranial pressure before treatment and Glasgow coma scale (GCS) scores were found among the 3 groups (P>0.05).Significant differences on the prognosis were found among the 3 groups (x2=6.671, P=0.036). Determined from the average rank, the prognosis in group A was better than that in group B, and the prognosis in group B was better than that in the control group. Conclusion Local mild hypothermia therapy within 8h of injury has functional benefit in the recovery of patients with DAI and improves their prognosis.     

8-hydroxy-2-(di-n-propylamino)tetralin intervenes with neural cell apoptosis following diffuse axonal injury

Previous studies have reported a neuroprotective effect of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) against traumatic brain injury. In accordance with the Marmarou method, rat models of diffuse axonal injury were established. 8-OH-DPAT was intraperitoneally injected into model rats 8-OH-DPAT treated rats maintained at constant temperature served as normal temperature controls TUNEL results revealed that neural cell swelling, brain tissue necrosis and cell apoptosis occurred around the injured tissue. Moreover, the number of Bax-, Bcl-2- and caspase-3-positive cells increased at 6 hours after diffuse axonal injury, and peaked at 24 hours. However, brain injury was attenuated, the number of apoptotic cells reduced, Bax and caspase-3 expression decreased, and Bcl-2 expression increased at 6, 12, 24, 72 and 168 hours after diffuse axonal injury in normal temperature control and in 8-OH-DPAT-intervention rats. The difference was most significant at 24 hours. All indices in 8-OH-DPAT-intervention rats were better than those in the constant temperature group. These results suggest that 8-OH-DPAT inhibits Bax and caspase-3 expression, increases Bcl-2 expression, and reduces neural cell apoptosis, resulting in neuroprotection against diffuse axonal injury. This effect is associated with a decrease in brain temperature.     

脑源性神经营养因子基因转染可促进弥漫性轴突损伤神经元修复和轴突再生

应用脂质体将外源脑源性神经营养因子基因导入弥漫性轴突损伤模型大鼠脑内,力图通过脑源性神经营养因子促进神经元再生及修复的作用,促进损伤大鼠的形态功能恢复。结果显示基因转染后弥漫性轴突损伤额叶皮质神经元的形态得到改善,额叶皮质组织神经丝蛋白表达增加,证实脑源性神经营养因子可促进弥漫性轴突损伤后神经元的修复及轴突的再生。     

Rosiglitazone ameliorates diffuse axonal injury by reducing loss of tau and up-regulating caveolin-1 expression

Rosiglitazone up-regulates caveolin-1 levels and has neuroprotective effects in both chronic and acute brain injury. Therefore, we postu-lated that rosiglitazone may ameliorate diffuse axonal injuryvia its ability to up-regulate caveolin-1, inhibit expression of amyloid-beta precursor protein, and reduce the loss and abnormal phosphorylation of tau. In the present study, intraperitoneal injection of rosiglitazone signiifcantly reduced the levels ofamyloid-beta precursor protein and hyperphosphorylated tau (phosphorylated at Ser404 (p-tau (S404)), and it increased the expression of total tau and caveolin-1 in the rat cortex. Our results show that rosiglitazone inhibits the expression of amyloid-beta precursor protein and lowers p-tau (S404) levels, and it reduces the loss of total tau, possibly by up-regulating caveolin-1. These actions of rosiglitazone may underlie its neuroprotective effects in the treatment of diffuse axonal injury.     

Endogenous adult neurogenesis and cognitive function recovery following traumatic brain injury in the rat hippocampus

BACKGROUND:Endogenous neural progenitor cells play a beneficial role for cognitive recovery following traumatic brain injury.However,there are few classification-control studies aimed at varying graded brain trauma.OBJECTIVE:To observe the effects of adult endogenous neurogenesis on cognitive function repair and regeneration of neural progenitor cells following varying graded traumatic hippocampal injury to determine the significance of endogenous neurogenesis in the repair of brain injury.DESIGN,TIME AND SETTING:A randomized,controlled,animal experiment was performed at the Key Laboratory of Injuries,Variations and Regeneration of Nervous System,Tianjin Medical University General Hospital,from February to October 2009.MATERIALS:Mouse anti-rat 5-bromodeoxyuridine (BrdU) and neuronal nuclei (NeuN) monoclonal antibodies were purchased from Millipore Corporation,USA.METHODS:A total of 45 Wistar rats were randomly assigned to three groups.Mild and severe injury groups were respectively subjected to (182 ± 2) kPa and (284 ± 4) kPa lateral fluid percussion to establish models of brain injury,and the control group was subjected to surgery with no lateral fluid percussion.MAIN OUTCOME MEASURES:Cognitive function was estimated using the Morris water maze.Proliferation,survival,and differentiation of newly generated cells in the injured hippocampus were observed through the use of immunofluorescent staining.RESULTS:At 7 days post-injury,the number of BrdU+ cells in the hippocampal dentate gyrus significantly increased in the mild and severe injury groups compared with the control group (P<0.01).At 61 days post-injury,the number of BrdU7NeuN+ cells in the hippocampal dentate gyrus was significantly greater in the mild injury group compared with the severe injury and control groups (P< 0.01).In addition,the control group exhibited the greatest proportion of surviving cells that differentiated into mature neurons compared with the injury groups (P< 0.01).Moreover,at 61 days post-injury,cognitive function in rats with mild injury recovered to normal levels,whereas the severe injury group exhibited cognitive deficits (P< 0.01).CONCLUSION:Traumatic brain injury may be a stimulation factor for proliferation of neural progenitor cells in the adult hippocampus but severe brain trauma does not lead to an increased number of newly generated cells.Endogenous adult neurogenesis repairs neurological functions to an extent.However,recovery of neurological function remains limited following severe traumatic brain injury.     

纳洛酮干预对大鼠弥漫性轴索损伤后突触素表达的影响

目的探讨弥漫性轴索损伤(diffuse axonal injury,DAI)后纳洛酮干预对突触素表达的影响。方法 99只Wistar雄性大鼠随机分为对照组、损伤组、纳洛酮干预组,对照组为假损伤,后两组采用改良的Marmarou大鼠颅脑DAI模型。伤后分别检测突触素表达变化情况,同时评价行为学功能和观察病理变化。结果伤后6 h、24 h,对照组行为学评分显著高于纳洛酮干预组(均P<0.01),同时纳洛酮干预组显著高于损伤组(均P<0.05)。大鼠致伤后,损伤组及纳洛酮干预组基底池、颅底可见轻度蛛网膜下腔出血,但无大面积或局灶性挫裂伤。光镜下见损伤组伤后24 h病理损害最严重,尼氏体数目显著减少、体积变小,甚至溶解消失,纳洛酮干预组上述改变有不同程度减轻。DAI后,突触素免疫阳性反应产物平均积分光密度(IOD)值分析表明:对照组IOD值高于损伤组(P<0.01)及纳洛酮干预组(P<0.05);损伤组DAI后突触素表达下降,24 h表现最为明显(P<0.01);纳洛酮干预组表达下降程度减轻,伤后6～72 h突触素表达显著高于损伤组(P<0.05),且24 h差异最明显(P<0.01)。结论早期纳洛酮干预对DAI后大...