DISC1在精神分裂症发病机制中的作用

染色体（1;11）（q42．1;q14．3）平衡易位后会引起断点部位精神分裂症断裂基因1（disrupted—in—schizophrenia-1,DISC1）突变。DISC1是很多精神疾病的潜在易感基因,已有研究表明,DISC1的基因突变、单核苷酸多态性与精神分裂症、双相障碍等精神疾病的发病都有密切关系。但是DISC1参与精神疾病发病的作用机制还不清楚。近年来,有关DISC1的生物学特性,生理功能以及参与精神疾病发病的研究不断深入。我们对目前的研究现状作一综述。     

DTNBP1基因多态性与精神分裂症的研究进展

精神分裂症是以严重的精神障碍为特征的复杂疾病之一,发病机制尚未明确。研究表明该病由多个微效基因与环境因素共同作用导致,遗传因素发挥更至关重要的作用。DTNBP1基因作为精神分裂症的易感基因之一,对谷氨酸、多巴胺等神经递质具有调控作用,与神经递质假说密切相关。目前,国内外已广泛研究DTNBP1基因单核苷酸多态性与精神分裂症易感性及其临床症状之间的关联性,本文主要就已有研究进展做一综述。     

SB-399885阻断5-羟色胺6受体/雷帕霉素靶蛋白 途径对精神分裂症大鼠认知和记忆障碍的改善作用

目的 研究 5- 羟色胺 6 受体（HTR6）拮抗剂 SB-399885 通过阻断 HTR6 / 雷帕霉素靶蛋 白（mTOR）途径对精神分裂症大鼠认知和记忆障碍的作用。方法 将 40 只 SD 大鼠随机分为 4 组：空 白对照组、精神分裂症模型组（SZ 组）、SZ+SB-399885 组（10 mg/kg）、阳性对照组（SZ+ 利培酮,0.1 mg/kg）, 每组各 10 只大鼠。采用 MK-801 建立 SZ 大鼠模型。新物体辨别实验检测大鼠视觉识别记忆,Morris 水 迷宫实验检测大鼠认知能力,被动回避实验检测大鼠学习记忆能力,乙酰胆碱酯酶（AChE）活性测定 试剂盒检测大鼠海马和大脑皮质 AChE 活性,TUNEL 染色法检测大鼠海马 CA1 区神经细胞凋亡情况, Western blot 检测大鼠海马 HTR6 / mTOR 途径相关蛋白的表达。 结果 5-HT6 受体拮抗剂 SB-399885 和 利培酮均能显著改善 SZ 大鼠视觉识别记忆障碍、认知障碍和学习记忆障碍（均P＜0.05）。与SZ组比较, SZ+SB-399885组大鼠海马AChE活性［（0.008±0.001）μmol/（min·mg）］、神经细胞凋亡率［（21.75±4.45）%］、 HTR6 蛋白表达（0.56±0.10）和 mTOR 活性（0.41±0.05）均显著降低（均P＜ 0.05）;阳性对照组大鼠海马 和大脑皮质 AChE 活性显著降低（均P＜ 0.05）,大鼠海马神经细胞凋亡率［（19.28±5.22）%］、HTR6 蛋 白表达（0.40±0.10）和 mTOR 活性（0.33±0.05）均显著降低（均P＜ 0.05）。结论 5-HT6 受体拮抗剂 SB- 399885 可能通过阻断 HTR6 / mTOR 途径改善精神分裂症大鼠认知和记忆障碍。     

抗精神病药在精神分裂症表观遗传调控中的研究进展

<正>精神分裂症是受基因和环境因素双重影响的复杂精神疾病。精神分裂症易感基因的遗传缺陷和表观遗传调控分子相互作用可导致疾病发生。目前已知表观遗传调控紊乱主要包括DNA甲基化、组蛋白修饰异常以及微小RNA(microRNA,miRNA)表达失调等。理论上,表观遗传修饰具     

精神分裂症临床综合征与表型

大量家系研究、双生子以及寄养子研究表明,遗传因素在精神分裂症病因学中起着非常重要的作用。然而,目前精神分裂症遗传因素的研究成果很不理想,至今没有发现病因学的特别基因,并且大部分研究的阳性结果缺乏稳定的重复性。精神分裂症表型遗传的异质性被认为是造成这种现象的主要原因。有些研究者认为精神分裂症的易感基因并不是单纯决定精神分裂症这一疾病本身,而且决定着疾病的临床症状群,或者疾病的神经认知缺陷。     

Presenilin l基因研究进展

阿尔采末氏病（Alzheimer’sdisease,AD）是一种中枢神经系统原发性退行性变性疾病,可导致痴呆及死亡。老年斑和神经纤维缠结为AD两大病理特征。老年斑的主要化学成分是p淀粉样蛋白（Ap）,由B淀粉样蛋白前体（ann）经性质未明蛋白酶（p或y分泌酶）剪切产生［‘］。大多数AD呈散发型,少数患者具有家族性,为常染色体显性遗传（FAD）。已知三个基因突变可以导致FAD。第一个是APP基因,突变频率非常低。大多数FAD与14号染色体上的早老素1（p。enillnl,pSI）基因突变连锁［‘－‘］。1号染色体上的PSZ基因也与少数FAD有关。PS…     

DNA甲基化在精神分裂症中的研究

精神分裂症的发病率大约1%[1].他的病因十分复杂,虽然该病是一种遗传相关的疾病,但目前尚未发现与这种疾病直接相关的特异性的基因.遗传与环境因素之间复杂相互作用是精神分裂症的主要病因[2].     

高分辨率熔解曲线分析对96例精神分裂症与96例对照DISC1基因外显子的突变检测

目的 对精神分裂症患者的DISC1(精神分裂症断裂基因1)基因的全部外显子进行突变筛查,以求发现突变.方法 使用聚合酶联反应对96例精神分裂症患者及96例正常对照者的DNA样本进行扩增,使用Light Scanner高分辨率熔解曲线(HRM)分析系统进行DISC1基因全部的13个外显子的突变检测,比较精神分裂症患者与正常对照者的熔解曲线.结果 所有精神分裂症患者的DISC1基因外显子中未发现突变.结论 对精神分裂症患者DISC1基因外显子的初步突变筛查未能发现突变.     

CLTCL1 基因 rs1061325 位点多态性与中国 汉族精神分裂症的关联分析

目的 探讨中国汉族人群网格蛋白重链 1（CLTCL1）基因 rs1061325 多态性与精神分裂症 的相关性。方法 选取 2007— 2008 年在上海交通大学医学院附属精神卫生中心门诊或住院的 662 例 精神分裂症患者作为病例组，选取同期的 414 名健康志愿者作为对照组。采用 TaqMan 探针基因分型技 术对两组的 CLTCL1 基因 rs1061325 位点进行分型，采用阳性与阴性症状量表（PANSS）对病例组进行精 神症状严重程度评定，并分析 PANSS 评分与不同基因型的相关性。结果 病例组与对照组的 rs1061325 等位基因和基因型频率分布比较，差异无统计学意义（χ2 =0.25、0.28，P=0.62、0.87）；在共显性、显性、隐 性、超显性、加性遗传模式下基因型分布差异也无统计学意义（P＞ 0.05），rs1061325 基因型多态性对精 神分裂症患者的发病年龄［（24.15±6.71）岁］、病程［（31.23±9.49）年］和 BMI［（26.46±5.28）kg/m2 ］也均 无明显影响（F=1.15、0.33、0.75，P=0.32、0.72、0.48），rs1061325 基因型多态性与 PANSS 阳性症状分、阴 性症状分、一般精神病理分及 PANSS 总分无相关性（F=1.26、0.37、0.34、0.49，P=0.29、0.69、0.72、0.62）。 结论 在中国汉族人群中，CLTCL1 基因 rs1061325 位点与精神分裂症无关联。     

DISC1基因对神经干细胞生长发育及癫发生机制研究

精神分裂症断裂基因1(DISC1)广泛表达于脑组织,对神经元生长发育的多个阶段,如增殖、迁移、分化和成熟均发挥调控作用。DISC1基因不仅与精神分裂症、双相情感障碍和重度抑郁症等精神病的发病机制相关,还参与神经系统疾病,如癫的发生与发展。中南大学湘雅医院肖波教授研究团队致力于研究DISC1基因及其相关蛋白在神经干细胞生长发育及癫发生发展中的调控作用。本文结合既往研究,展示我们研究团队相关成果,总结DISC1基因及其相关蛋白在神经干细胞生长发育及癫发生发展中的分子生物学机制。     

Diagnostic Difficulties and Treatment Implications

Summary: Differentiation between types of epileptic seizures has been aided in recent years by the introduction of intensive neurodiagnostic techniques and the development of increasingly detailed classification systems. Paradoxically, these developments have not simplified the task of matching the appropriate antiepileptic drug to a particular seizure type. It is reasonable to assume that anticonvulsant drugs will have different effects on different types of seizures, but faulty, circular reasoning can enter the picture if one also assumes that responses of seizures to different drugs signify different seizure types. There are several examples of differential diagnoses that can fall prey to this problem, including the diagnosis between partial seizures with secondary generalization and generalized tonic-clonic seizures, and the diagnosis between complex partial seizures and absence seizures with automatisms, among others. Considerations of etiology in future classification systems can further complicate the problem: should one then choose an anticonvulsant drug on the basis of individual seizure type or on the basis of the type of epilepsy? Ramifications of this issue extend even to the drug approval process. Official sanction is not given for use of a drug for a seizure type not included in the original efficacy studies, even if later scientific evidence shows that seizure type to be related to a type that is included. New trials must be undertaken. These problems arise from how we choose to classify seizures.     

Cognitive Dysfunction Associated with Antiepileptic Drug Therapy

Summary: Epilepsy is frequently associated with cognitive dysfunction. However, the reasons for this correlation are unclear. Possible influential factors include patient age; duration, frequency, etiology, and type of seizures; hereditary factors; psychosocial issues; and antiepileptic drug (AED) therapy. Whereas many of these factors are beyond the physician's control, AED therapy is one element that can be addressed in treatment decisions by recognizing the potential cognitive effects of particular AEDs. For example, phenobarbital impairs memory and concentration; phenytoin affects attention, problem solving ability, and performance of visuomotor tasks. In contrast, carbamazepine may affect concentration, while valproate would appear to have minimal effects on cognition. Moreover, cognitive effects of AEDs are amplified with coadministration of multiple anticonvulsants (polytherapy). A review of studies on the cognitive effects of monotherapy with AEDs, as opposed to those of polytherapy, provides evidence that drug-related cognitive dysfunction can be reversed if patients are switched to a simpler therapeutic regimen. Future research should be directed toward developing reliable measures for assessing and monitoring cognition, and understanding the particular cognitive side effects of each AED. Physicians also need to revise their opinions about which side effects are "tolerable" for epileptic patients.     

Hepatic Considerations in the Use of Antiepileptic Drugs

Summary: Virtually all of the major antiepileptic drugs (AEDs) can cause hepatotoxicity, although fatal hepatic reactions are rare. The mechanisms, incidences, and risk profiles for such reactions differ from drug to drug. With carbamazepine and phenytoin, hepatotoxicity may be due to drug hypersensitivity. Although the profiles of patients at risk have not been well-defined for these two antiepileptic drugs, it would appear from reports in the literature that older adolescents and adults are at higher risk than children of developing serious or fatal hepatotoxicity. Once hepatotoxicity develops, mortality rates are 10–38% with phenytoin and 25% for carbamazepine. The risk profile for valproate fatal hepatotoxicity has been more clearly defined. Those at primary risk of fatal hepatic dysfunction are children under the age of 2 years who are receiving multiple anticonvulsants and also have significant medical problems in addition to severe epilepsy. The risk is considerably lower for patients over the age of 2 years on valproate monotherapy. In contrast to the risk profile with other AEDs, adults receiving valproate as monotherapy have the lowest risk of hepatotoxicity. Fatal hepatic dysfunction coincident with valproate may be the result of aberrant drug metabolism. Concomitant use of AEDs that induce microsomal P450 enzymes (e.g., phenytoin and phenobarbital) may enhance the production of a toxic metabolite, and hence the greater risk of hepatotoxicity with polypharmacy.     

Vascular Malformations and Epilepsy: Clinical Considerations and Basic Mechanisms

Summary: Vascular malformations (VMs) are associated with epilepsy. The natural history of the various VMs, clinical presentation, and tendency to provoke epilepsy determine treatment strategies. Investigations have probed the mechanisms of epileptogenesis associated with these lesions. Electrophysiologic changes are associated with epileptogenic cortex adjacent to VMs. Putative pathophysiologic mechanisms of epileptogenesis include neuronal cell loss, glial proliferation and abnormal glial physiology, altered neurotransmitter levels, free radical formation, and aberrant second messenger physiology.     

Carbamazepine Efficacy in Adults With Partial and Generalized Tonic-Clonic Seizures

Summary: Carbamazepine and phenytoin are drugs of choice in initial monotherapy for adult partial and secondarily generalized tonic-clonic seizures. These designations reflect the results of the Veterans Administration Epilepsy Cooperative Study Group of 1985. An earlier comparative study of carbamazepine and phenytoin by Ramsay and associates found both drugs equally effective in controlling new-onset seizures. Among the advantages of carbamazepine is that it causes relatively few cognitive and dysmorphic side effects. Its disadvantages are its unavailability in parenteral formulation and its metabolic autoinduction. The latter must be compensated for by planned dosage increases to maintain therapeutic plasma steady-state levels during the first 2 or 3 months of treatment. Carbamazepine is judged a drug of choice in the treatment of these secondarily generalized tonic-clonic seizures, and the drug of choice in children, adolescents, and women susceptible to the dysmorphic side effects associated with other anticonvulsant agents.     

Etiologic and Preventive Aspects of Epilepsy in the Child–Bridging the Gap Between Laboratory and Clinic

Summary: Four broad categories of basic phenomena are pertinent to developing ways to prevent epilepsy. These include mechanisms of epileptogenesis, ictal initiation and temporary entrainment by the seizure discharge of normally functioning brain, seizure propagation, and control mechanisms that function both to restrain the cascade of epileptic events culminating in a seizure and to arrest the epileptic event and restore the interictal state. In newborns and children, hypoxia-ischemia is a major factor leading to epileptogenesis, and several schemes are proposed to classify, quantify, and prevent hypoxic-ischemic encephalopathy. Control mechanisms must be better understood in order to develop prophylactic recommendations for epilepsy, and an experimental model of "kindling antagonism" may increase our understanding of these. Programs of prevention of seizures in children will evolve only if basic researchers and clinicians work productively together to develop an adequate understanding of factors important in epileptogenesis and antiepileptogenic control mechanisms.     

Epilepsy and anomalies of neuronal migration: MRI and clinical aspects

Neuronal migration disorders are the result of disturbed brain development. In such disorders, neurons are abnormally located. In diagnosing these conditions, magnetic resonance imaging is superior to any other imaging technique. This enables us to improve our knowledge of the clinical correlates of neuronal migration. With reference to migrational disorder, a retrospective study of all 303 patients with epileptic seizures referred for magnetic resonance imaging during a 3-year period was performed, 13 patients (aged 12-41, mean age 27) were identified. They represent 4.3% of the entire study group. Of the patients with known epilepsy, 6.7% and of the mentally retarded, 13.7% had migrational disorders. Four patients had schizencephaly as the dominant finding, one was classified as hemimegalencephaly, 2 had isolated heterotopias, and 6 had localized pachy- and/or poly-microgyria. The clinical pictures are complex. Ectopias of grey matter are recognised foci of epilepsy, but from an epileptological and a clinical viewpoint little attention has been given to these disorders. The present study shows that malmigration is not rare in epilepsy patients, especially not in the mentally retarded.     

Carbamazepine Efficacy and Utilization in Children

Summary: Carbamazepine is effective for preventing partial and generalized tonic-clonic seizures in children. Although absence epilepsies are more common in children than adults, an estimated 80% of children with epilepsy have seizure types or epilepsies that are potentially responsive to carbamazepine. The differential diagnosis of ictal staring is an especially important issue in children because absence and atypical absence seizures are more prevalent in children than adults. Age-related pharmacokinetic differences and drug interactions are major considerations in children. On average, children have higher clearance rates of carbamazepine, shorter half-lives, and higher ratios of carbamazepine-10, 11-epoxide to carbamazepine than adults. In addition, children with severe epilepsy are more likely to require multiple-drug therapy, which can lead to complex drug interactions. When carbamazepine is administered along with valproate, drug protein binding interactions can cause intermittent side effects.     

Predisposing and Causative Factors in Childhood Epilepsy

Summary: We review information from large studies of defined populations, examining the role of known factors and especially of prenatal and perinatal factors in contributing to nonfebrile seizure disorders of early childhood. We depend especially, but not exclusively, on the recently completed analyses from the Collaborative Perinatal Project of the National Institute of Neurological and Communicative Disorders and Stroke, the NCPP. About 4% of children in the NCPP who had at least one non-febrile nonsymptomatic seizure by the age of 7 years had a previous seizure during acute neurologic illness, such as meningitis or during the acute illness after trauma. Many such seizures should potentially be preventable. Of children with seizures, 10% had had a neonatal seizure and 13% had had a febrile seizure. Among the hundreds of prenatal and perinatal factors explored as predictors of childhood seizure disorders, the principal predictors identified were congenital malformations of the fetus, cerebral and noncerebral; family history of certain neurologic disorders; and neonatal seizures. In agreement with the British National Child Development Study, labor and delivery factors in the NCPP appeared to contribute very little to childhood seizure disorders. Maldevelopment, rather than damage at birth to an initially intact nervous system, appeared to be the more common mechanism. Most seizure disorders of early childhood remained unexplained by the large set of prenatal and perinatal characteristics examined.     

Anticonvulsant Drugs and Cognitive Function: A Review of the Literature

Summary: Alterations of cognitive function are separate from disturbances of behavior seen in association with epilepsy. The nature of the cognitive disability may to a certain extent depend on the seizure type. Partial seizures, mainly derived from a temporal lobe focus, impair memory tasks, while generalized seizures seem to have more effect on attentional abilities. A number of studies, reviewed in this paper, suggest that anticonvulsant drugs further impair cognitive function. Maximal impairments are seen in patients receiving polytherapy: rationalization of polytherapy improves cognitive abilities. Studies in children and adults have allowed differentiation of the effects of various commonly used antiepileptic agents. Maximal cognitive deficits are seen with. phenytoin, while phenobarbital and sodium valproate induce moderate disturbances, and carbamazepine seems relatively free from such toxicity. Further research is needed on the interrelationship between types of seizure disorders, types of anticonvulsant medications, and cognitive function.