伴海马硬化的颞叶癫痫患者海马组织内BDNF表达变化

目的：研究伴海马硬化的难治性颞叶癫痫（TLE）患者海马组织内脑源性神经营养因子（brain derivedneurotrophic factor,BDNF）的表达变化,探讨其在难治性颞叶癫痫发病机制中的作用。方法：采集5例伴海马硬化的难治性TLE患者手术中切除的海马组织,用逆转录-聚合酶链反应（RT—PCR）法检测BDNFmRNA表达,并与3例非海马硬化TLE患者对照。结果：与非海马硬化组比较,伴海马硬化的难治性TLE患者海马组织中的BDNFmRNA表达明显增加（P〈0．01）。结论：伴海马硬化的难治性TLE患者海马组织中BDNFmRNA表达表达增高,可能在海马硬化和难治性颞叶癫痫发生、发展中具有重要作用。     

CFA注射致炎性疼痛过程中海马内BDNF的表达及作用研究

目的:探索完全弗氏佐剂(Complete Freund’s Adjuvant,CFA)致炎性疼痛后大鼠海马内脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)表达的变化及其作用。方法:雄性SD大鼠随机分为溶媒对照组和实验组,实验组大鼠左侧足底皮下注射CFA和生理盐水混合溶剂100μL,建立炎性疼痛模型,注射后大鼠分别存活1天、4天、7天、14天(n=20只/组)。在建模前和建模后不同时间点采用Von Frey纤维检测大鼠50%机械缩足阈值(paw withdrawal threshold,PWT)的变化。采用强迫游泳实验和糖水偏好实验检测大鼠抑郁样行为,采用RT-PCR检测不同时间点大鼠海马中BDNF m RNA的水平,采用ELISA和免疫组织化学法检测BDNF的表达变化。结果:足底注射CFA后1天50%PWT下降,持续至14天仍低于基础值。在强迫游泳实验中,注射CFA7天后的大鼠不动时间百分比增加,一直持续到CFA注射后14天。糖水偏好实验中注射CFA后7天组、14天组大鼠表现出对糖水偏好的降低,提示注射CFA后7天大鼠出现抑郁样行为并持续到第14天。在足底注射CFA第7天后BDNF m RNA和BDNF的水平达到高峰,第14天表达下调并基本恢复正常水平。结论:结果提示,足底注射CFA能诱导大鼠产生炎性痛,CFA注射7天后出现抑郁样行为,此时海马内BDNF m RNA和BDNF蛋白水平均上调,可能与足底注射CFA后出现的抑郁样行为的发生密切相关。     

MST3在颞叶癫痫模型小鼠海马的表达变化

目的观察海人酸(kainic acid,KA)所致癫痫(epilepsy,EP)小鼠海马Ste20蛋白激酵素(MST3)表达水平的变化,探讨MST3在癫痫发病过程中的可能作用。方法选用成年雄性小鼠,并随机分成模型组和对照组。模型组小鼠侧脑室注射2μL(100 ng/μL)KA,分别于术后3、8、24 h收集动物标本以进行检测。使用RT-PCR和Western Blot测定MST3 mRNA含量和MST3蛋白动态表达变化,应用免疫组化观察MST3在海马的表达分布与特点。结果与正常对照组相比,模型组海马组织内MST3mRNA的表达随时间持续升高,24 h达到高峰;MST3的蛋白表达也表现出同样的动态升高趋势;术后3～24 h的模型组海马免疫组化检测显示,模型组MST3主要以海马齿状回、门回区、CA3区域表达增加为主,并且这些区域表达逐渐递增。结论随着时间的推移,MST3表达水平呈现逐渐增加趋势,可能与神经元损伤造成的凋亡之间有密切的关系,提示MST3可能在癫痫发病过程中起重要作用。     

大鼠肠道菌群变化影响其大脑海马脑源性神经营养因子的表达

目的探讨大鼠肠道菌群变化对海马脑源性神经营养因子(Brain-Derived Neurotropic Factor,BDNF)的影响。方法在雄性SD大鼠的饮用水中添加肠道不吸收的抗生素(新霉素、杆菌肽和游霉素),饮用1周、3周之后检测大鼠体重,采用变性梯度凝胶电泳(Denaturing Gradient Gel Electrophoresis,DGGE)的方法检测大鼠粪便中菌群的组成,并用实时定量PCR检测大鼠大脑海马BDNF的表达水平。结果与对照组相比,饮用抗生素的大鼠体重无明显差异,而肠道菌群有显著变化;抗生素饮用组海马BDNF的表达水平升高(P0.05)。结论肠道菌群变化可以影响大脑海马BDNF的表达。     

慢性脑低灌注大鼠海马BDNF的表达与认知功能损害

目的　观察慢性脑低灌注大鼠认知功能损害与海马脑源性神经营养因子 (Brain derivedneurotrophicfactor,BDNF)表达的关系。方法　通过结扎大鼠双侧颈总动脉 ,制成慢性脑低灌注模型 ,分缺血 6周组和 4月组及相应假手术组 ,在相应时间点用三等份MG 2Y型迷宫法测定大鼠学习记忆能力。用免疫组化S P法检测 4组大鼠海马中BDNF的表达 ,在光镜下测其平均光密度。结果　显示手术组与假手术组相比学习记忆能力明显下降 ,慢性脑低灌注大鼠缺血 4月组与缺血 6周组相比学习记忆能力也下降 (P <0 0 5 )。缺血 4月组大鼠海马BDNF表达的平均光密度值与Y型迷宫实验正确次数间存在正相关 (r=0 782 5 ,P <0 0 5 )。结论　表明在慢性脑低灌注状态下 ,大鼠学习记忆能力随海马BDNF表达的下降而下降 ,内源性BDNF可能通过对突触传递和认知功能有内在保护作用。     

新生大鼠海马分区培养神经元对缺氧反应的差异

本文以混合培养海马神经元技术为基础,通过改进解剖方法、摸索鼠龄与存活率之间的关系,成功地进行了海马神经凶的分区培养。同时采用同视野跟踪记数法、激光扫描共降焦显微镜测钙和原位杂交等技术,研究了缺氧条件下培养的海马ＣＡ１和ＤＧ神经元存在活率、细胞内游离钙和脑源性神经营养因子（ＢＤＮＦ）ｍＲＮＡ表达水平等指标上变化的差异。结果表明,在相同的缺氧条件下,ＤＧ细胞比ＣＡ１细胞损伤轻微并且具有比ＣＡ１细胞更强     

黄连浸出液对脑缺血大鼠海马区BDNF mRNA表达的影响

为了探究黄连浸出液对局灶性脑缺血再灌注大鼠海马区脑源性神经营养因子(BDNF)mRNA表达的影响,本研究随机将50只雄性SD大鼠(240±20) g分为假手术组、模型组、黄连浸出液低剂量(2.5 g/kg)、中剂量(5.0 g/kg)和高剂量(10.0 g/kg)治疗组,采用线栓法建立大鼠局灶性脑缺血(MCAO)模型,假手术组不予线栓处理,术后对大鼠进行神经功能评分。对各治疗组给予灌胃治疗,按照人和大鼠等效剂量关系换算,每只大鼠1d灌胃两次,每次2.5 mL,连续灌胃3d。模型组、假手术组用等量生理盐水灌胃。应用RT-PCR测定了黄连浸出液对局灶性脑缺血再灌注大鼠海马区BDNF表达的影响。与假手术组(BDNF mRNA相对表达量为(0.386±0.011)比较),模型组大鼠海马区BDNF mRNA表达显著增加,相对表达量为(0.458±0.029),差异具有统计学意义(p0.05);与模型组比较,黄连中剂量和高剂量治疗组BDNF mRNA的表达均显著增加,相对表达量分别为(0.622±0.040)和(0.518±0.033),差异均有统计学意义(p0.05);与黄连高剂量组相比,中剂量治疗组差异更为显著(p0.05)。本研究表明,黄连浸出液可促进脑缺血再灌注损伤大鼠海马区BDNF mRNA的表达,改善脑缺血再灌注损伤大鼠的神经功能,保护神经元,黄连浸出液中剂量(5.0 g/kg)作用更为明显。     

海马硬化对癫痫敏感性的影响

癫痫是一种常见的神经系统疾病,随着神经影像学诊断技术的发展,海马硬化与癫痫的关系日益受到重视,报道约有60%～70%的癫痫患者伴有一侧海马硬化。动物研究发现癫痫敏感性长期增强的动物常伴有海马硬化,但二者的因果关系尚难以确定。全蝎是我国传统的抗癫痫药材,本实验室己证实全蝎具有防止癫痫敏感性形成的功效。本工作旨在用抗癫痫敏感性形成的手段观察海马硬化在癫痫敏感性形成中的作用。1　材料与方法(1)ＢｍＫ粗提液的制备　选用东亚钳蝎(ＢｕｔｈｕｓＭａｒｔｅｎｓｉｉＫａｒｓｃｈ,Ｂｍｋ)。去盐,42℃烘干并研成粉末,然后用生理盐水…     

电针联合天麻多糖对脑缺血大鼠海马CA3区Nesin、BDNF表达的影响

目的观察电针联合天麻多糖对脑缺血大鼠海马CA3区巢蛋白(Nestin)和脑源性神经营养因子(brain derived neurotrophic factor,BDNF)表达的影响。方法将40只SD大鼠随机分为正常对照组、模型组、电针组、天麻多糖组和针药结合组,每组8只。以单侧大脑中动脉栓塞法制备脑缺血模型。造模后2w,天麻多糖组和针药结合组大鼠给予天麻多糖100mg/kg灌胃,每天1次,连续2w;电针组和针药结合组大鼠给予"百会""足三里"穴电针刺激,持续30min,每天1次,连续2w。采用免疫组织化学染色法结合图像分析检测海马CA3区Nestin和BDNF的表达。结果与正常对照组比较,模型组缺血侧海马CA3区Nestin和BDNF阳性表达增加(P0.05);与模型组比较,电针组、天麻多糖组和针药结合组缺血侧海马CA3区Nestin和BDNF阳性表达显著增加(P0.05);针药结合组阳性表达显著多于电针组或天麻多糖组(P0.05)。结论电针与天麻多糖结合可显著增加脑缺血大鼠缺血侧海马CA3区Nestin和BDNF的表达,促进内源性神经干细胞激活,且作用优于单用电针或天麻多糖。     

浅析BDNF改善痴呆老龄鼠记忆障碍CA1区GrayⅠ型突触结构相关参数的变化

目的探讨BDNF（Brain derived neurotrophic factor）改善痴呆老龄鼠记忆障碍的机制。方法利用Morris迷宫试验观察脑内微量注射BDNF对痴呆小鼠自发活动和记忆巩固过程的影响,应用透射电镜和形态计量学分析痴呆老龄鼠海马GrayⅠ型突触的突出结构参数的变化。结果BDNF使痴呆小鼠在新异环境中的自发活动和探究行为明显增多;并显著延长电击后24 h的步入潜伏期（STL）;BDNF使痴呆老龄鼠海马CA1区GrayⅠ型突触的体积密度、面积密度、比表面和面数密度较治疗前增大,突触平均面积增大;突出界面曲率、突出间隙宽度、突出后致密物质均较治疗前增大,而较正常对照组减小。结论突触结构的变化和突出数量的减少是痴呆发病的病理机制之一;BDNF能够促进突触重建,改善痴呆老龄鼠的学习记忆。     

Mitophagy in Refractory Temporal Lobe Epilepsy Patients with Hippocampal Sclerosis

This study aimed to determine if there is an association between mitophagy and refractory temporal lobe epilepsy (rTLE) with hippocampal sclerosis. During epilepsy surgery, we collected tissue samples from the hippocampi and temporal lobe cortexes of rTLE patients with hippocampal sclerosis (as diagnosed by a pathologist). Transmission electron microscopy (TEM) was used to study the ultrastructural features of the tissue. To probe for mitophagy, we used fluorescent immunolabeling to determine if mitochondrial and autophagosomal markers colocalized. Fourteen samples were examined. TEM results showed that early autophagosomes were present and mitochondria were impaired to different degrees in hippocampi. Immunofluorescent labeling showed colocalization of the autophagosome marker LC3B with the mitochondrial marker TOMM20 in hippocampi and temporal lobe cortexes, indicating the presence of mitophagy. Mitochondrial and autophagosomal marker colocalization was lower in hippocampus than in temporal lobe cortex (P < 0.001). Accumulation of autophagosomes and mitophagy activation are implicated in rTLE with hippocampal sclerosis. Aberrant accumulation of damaged mitochondria, especially in the hippocampus, can be attributed to defects in mitophagy, which may participate in epileptogenesis.     

fMRI颞叶癫痫默认模式网络的研究

许多功能磁共振研究已经发现人脑的一些皮层区域在静息状态下出现共激活,这些区域形成连通的功能网络,称为"默认模式网络"。本文研究颞叶癫痫患者的默认模式网络,运用独立成分分析(Independent component analysis)分离出12例颞叶癫痫患者和12例正常对照的默认模式网络,进行组内分析得到两组被试的统计图,进行组间分析比较两组被试的默认模式网络的差异。结果表明默认模式网络均存在于颞叶癫痫患者和正常对照中,然而,在默认模式包含的网络中,颞叶癫痫患者前扣带回腹侧(ventral anterior cingulated cortex,vACC)、前额中分(medial prefrontal cortex,MPFC)、楔前叶(precuneus)、以及海马旁回区域比正常对照表现出代谢增强。这一结果有助于从脑功能的角度了解癫痫患者某些临床症状的发病机理,为今后癫痫诊治的发展提供一定的帮助。     

Frequent Seizures Are Associated with a Network of Gray Matter Atrophy in Temporal Lobe Epilepsy with or without Hippocampal Sclerosis

Objective

Patients with temporal lobe epilepsy (TLE) with hippocampal sclerosis (HS) have diffuse subtle gray matter (GM) atrophy detectable by MRI quantification analyses. However, it is not clear whether the etiology and seizure frequency are associated with this atrophy. We aimed to evaluate the occurrence of GM atrophy and the influence of seizure frequency in patients with TLE and either normal MRI (TLE-NL) or MRI signs of HS (TLE-HS).

Methods

We evaluated a group of 172 consecutive patients with unilateral TLE-HS or TLE-NL as defined by hippocampal volumetry and signal quantification (122 TLE-HS and 50 TLE-NL) plus a group of 82 healthy individuals. Voxel-based morphometry was performed with VBM8/SPM8 in 3T MRIs. Patients with up to three complex partial seizures and no generalized tonic-clonic seizures in the previous year were considered to have infrequent seizures. Those who did not fulfill these criteria were considered to have frequent seizures.

Results

Patients with TLE-HS had more pronounced GM atrophy, including the ipsilateral mesial temporal structures, temporal lobe, bilateral thalami and pre/post-central gyri. Patients with TLE-NL had more subtle GM atrophy, including the ipsilateral orbitofrontal cortex, bilateral thalami and pre/post-central gyri. Both TLE-HS and TLE-NL showed increased GM volume in the contralateral pons. TLE-HS patients with frequent seizures had more pronounced GM atrophy in extra-temporal regions than TLE-HS with infrequent seizures. Patients with TLE-NL and infrequent seizures had no detectable GM atrophy. In both TLE-HS and TLE-NL, the duration of epilepsy correlated with GM atrophy in extra-hippocampal regions.

Conclusion

Although a diffuse network GM atrophy occurs in both TLE-HS and TLE-NL, this is strikingly more evident in TLE-HS and in patients with frequent seizures. These findings suggest that neocortical atrophy in TLE is related to the ongoing seizures and epilepsy duration, while thalamic atrophy is more probably related to the original epileptogenic process.     

Cognitive and Surgical Outcome in Mesial Temporal Lobe Epilepsy Associated with Hippocampal Sclerosis Plus Neurocysticercosis: A Cohort Study

Background

Where neurocysticercosis (NCC) is endemic, chronic calcified neurocysticercosis (cNCC) can be observed in patients with mesial temporal lobe epilepsy associated with hippocampal sclerosis (MTLE-HS). Considering that both disorders cause recurrent seizures or cognitive impairment, we evaluated if temporal lobectomy is cognitively safe and effective for seizure control in MTLE-HS plus cNCC.

Methods

Retrospective cohort study of neuropsychological profile and surgical outcome of 324 MTLE-HS patients submitted to temporal lobectomy, comparing the results according to the presence or absence of cNCC.

Findings

cNCC occurred in 126 (38.9%) of our MTLE-HS patients, a frequency higher than expected, more frequently in women than in men (O.R. = 1.66; 95% C.I. = 1.05–2.61; p = 0.03). Left-side (but not right side) surgery caused impairment in selected neuropsychological tests, but this impairment was not accentuated by the presence of cNCC. Ninety-four (74.6%) patients with MTLE-HS plus cNCC and 153 patients (77.3%) with MTLE-HS alone were Engel class I after surgery (O.R. = 1.16; 95% C.I. = 0.69–1.95; p = 0.58). However, the chances of Engel class IA were significantly lower in MTLE-HS plus cNCC than in patients with MTLE-HS alone (31.7% versus 48.5%; O.R. = 2.02; 95% C.I. = 1.27–3.23; p = 0.003). Patients with MTLE-HS plus cNCC showed higher rates of Engel class ID (15.1% versus 6.6%; O.R. = 2.50; 95% C.I. = 1.20–5.32; p = 0.012).

Interpretation

cNCC can be highly prevalent among MTLE-HS patients living in areas where neurocysticercosis is endemic, suggesting a cause-effect relationship between the two diseases. cNCC does not add further risk for cognitive decline after surgery in MTLE-HS patients. The rates of Engel class I outcome were very similar for the two groups; however, MTLE-HS plus cNCC patients achieved Engel IA status less frequently, and Engel ID status more frequently. Temporal lobectomy can be safely performed in most patients with MTLE-HS plus cNCC without affecting cognitive outcome. Long-term surgical seizure control in MTLE-HS plus cNCC is still satisfactory, as long as selected patients remain under medication.     

Protective Effect of Resveratrol against Kainate-induced Temporal Lobe Epilepsy in Rats

Resveratrol (Res) is a phytoalexin produced naturally by several plants, which has multi functional effects such as neuroprotection, anti-inflammatory, and anti-cancer. The present study was to evaluate a possible anti-epileptic effect of Res against kainate-induced temporal lobe epilepsy (TLE) in rat. We performed behavior monitoring, intracranial electroencepholography (IEEG) recording, histological analysis, and Western blotting to evaluate the anti-epilepsy effect of Res in kainate-induced epileptic rats. Res decreased the frequency of spontaneous seizures and inhibited the epileptiform discharges. Moreover, Res could protect neurons against kainate-induced neuronal cell death in CA1 and CA3a regions and depressed mossy fiber sprouting, which are general histological characteristics both in TLE patients and animal models. Western blot revealed that the expression level of kainate receptors (KARs) in hippocampus was reduced in Res-administrated rats compared to that in epileptic ones. These results suggest that Res is a potent anti-epilepsy agent, which protects against epileptogenesis and progression of the kainate-induced TLE animal. The authors Z. Wu and Q. Xu contributed equally to this work.     

Network Analysis of the Default Mode Network Using Functional Connectivity MRI in Temporal Lobe Epilepsy

Functional connectivity MRI (fcMRI) is an fMRI method that examines the connectivity of different brain areas based on the correlation of BOLD signal fluctuations over time. Temporal Lobe Epilepsy (TLE) is the most common type of adult epilepsy and involves multiple brain networks. The default mode network (DMN) is involved in conscious, resting state cognition and is thought to be affected in TLE where seizures cause impairment of consciousness. The DMN in epilepsy was examined using seed based fcMRI. The anterior and posterior hubs of the DMN were used as seeds in this analysis. The results show a disconnection between the anterior and posterior hubs of the DMN in TLE during the basal state. In addition, increased DMN connectivity to other brain regions in left TLE along with decreased connectivity in right TLE is revealed. The analysis demonstrates how seed-based fcMRI can be used to probe cerebral networks in brain disorders such as TLE.     

颞叶癫痫脑“默认模式”的fMRI研究

功能磁共振成像(functional magnetic resonance imaging,fMRI)被用于检测静息时脑功能神经网络.作者运用静息fMRI检测海马硬化颞叶癫痫(temporal lobe epilepsy,TLE)脑"默认模式",采用感兴趣区域功能连接分析检测16例TLE患者和16名正常对照静息时脑的"默认模式",并进行组内和组间分析.研究发现,与正常对照相比,TLE静息时海马、颞极、额叶、颞叶、壳核及楔前叶等脑区与后扣带回的功能连接增强.研究结果表明TLE患者的固有脑功能组织模式有可能出现紊乱.这一研究将有助于从脑功能的角度了解癫痫患者某些临床症状的发病机理,为今后癫痫诊治的发展提供一定的帮助.     

Reduction of Hippocampal Collapsin Response Mediated Protein-2 in Patients with Mesial Temporal Lobe Epilepsy

Although the syndrome of mesial temporal lobe epilepsy (MTLE) associated with hippocampal sclerosis has been elaborated in recent years, pathogenesis and pathomechanisms are still elusive. Performing protein hunting in hippocampus of patients with MTLE we detected derangement of collapsin response mediated protein-2 (CRMP-2). Hippocampal tissue from controls and MTLEs was taken and two-dimensional gel electrophoresis with subsequent MALDI-MS-characterisation was applied. The proteomic approach identified 13 spots unambiguously assigned to CRMP-2. Three spots at molecular weight 55 kDa showed a significant decrease in MTLE and other 3 spots at 65 kDa showed deranged in MTLE. Immunoblotting revealed two bands at 65 and 55 kDa in the control group whereas the 55 kDa band was extremely low expressed in MTLE. CRMP-2 is required to induce axonal outgrowth and maintaining neuronal polarity in hippocampal neurons and the significant decrease of this protein may represent or underlie impaired neuronal plasticity, neurodegeneration, wiring of the brain in MTLE and may explain abnormal migration. Therefore, the decrease of CRMP-2 may well contribute to the understanding of the still unclear pathomechanisms involved in MTLE.     

Increased Metallothionein I/II Expression in Patients with Temporal Lobe Epilepsy

In the central nervous system, zinc is released along with glutamate during neurotransmission and, in excess, can promote neuronal death. Experimental studies have shown that metallothioneins I/II (MT-I/II), which chelate free zinc, can affect seizures and reduce neuronal death after status epilepticus. Our aim was to evaluate the expression of MT-I/II in the hippocampus of patients with temporal lobe epilepsy (TLE). Hippocampi from patients with pharmacoresistant mesial temporal lobe epilepsy (MTLE) and patients with TLE associated with tumor or dysplasia (TLE-TD) were evaluated for expression of MT-I/II, for the vesicular zinc levels, and for neuronal, astroglial, and microglial populations. Compared to control cases, MTLE group displayed widespread increase in MT-I/II expression, astrogliosis, microgliosis and reduced neuronal population. In TLE-TD, the same changes were observed, except that were mainly confined to fascia dentata. Increased vesicular zinc was observed only in the inner molecular layer of MTLE patients, when compared to control cases. Correlation and linear regression analyses indicated an association between increased MT-I/II and increased astrogliosis in TLE. MT-I/II levels did not correlate with any clinical variables, but MTLE patients with secondary generalized seizures (SGS) had less MT-I/II than MTLE patients without SGS. In conclusion, MT-I/II expression was increased in hippocampi from TLE patients and our data suggest that it is associated with astrogliosis and may be associated with different seizure spread patterns.