Early-Life Seizures and Development of GABAergic Inhibition in the Human Brain

人脑中早期癫痫发作和 GABA 能抑制的发展

• 批准号: 8189659
• 负责人: LAURA A JANSEN
• 金额: $ 18.46万
• 依托单位: SEATTLE CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2016-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8189659
• 关键词: 3 year old; Address; Age; Animal Model; Antibodies; Anticonvulsants; Astrocytes; Autopsy; Barbiturates; Benzodiazepines; Brain; Brain region; Cations; Cell membrane; Cells; Cellular Membrane; Child; Chloride Ion; Chlorides; Clinical; Cortical Malformation; Data; Databases; Detection; Development; Disease; Electrodes; Electrophysiology (science); Epilepsy; Exhibits; Exposure to; Fluorescence; Freezing; Frequencies; Funding; GABA Agents; Glutamates; Goals; Human; Human Development; Immunohistochemistry; In Situ Hybridization; Infant; Infant Care; Injection of therapeutic agent; Interneurons; K-Series Research Career Programs; Label; Life; Medical; Membrane; Modeling; Neonatal; Neurologic; Neurons; Oocytes; Operative Surgical Procedures; Outcome; Pathology; Patients; Pattern; Pharmaceutical Preparations; Play; Population; Pregnancy; Premature Infant; Preparation; Property; Pyramidal Cells; Relative (related person); Resected; Resistance; Role; Sedation procedure; Seizures; Specimen; Techniques; Therapeutic; Time; Western Blotting; Xenopus oocyte; age group; aged; barbituric acid salt; base; brain tissue; cell type; clinical application; early childhood; gamma-Aminobutyric Acid; improved; innovation; neonate; neurosteroids; receptor; sex; voltage clamp; 3 year old; Address; Age; Animal Model; Antibodies; Anticonvulsants; Astrocytes; Autopsy; Barbiturates; Benzodiazepines; Brain; Brain region; Cations; Cell membrane; Cells; Cellular Membrane; Child; Chloride Ion; Chlorides; Clinical; Cortical Malformation; Data; Databases; Detection; Development; Disease; Electrodes; Electrophysiology (science); Epilepsy; Exhibits; Exposure to; Fluorescence; Freezing; Frequencies; Funding; GABA Agents; Glutamates; Goals; Human; Human Development; Immunohistochemistry; In Situ Hybridization; Infant; Infant Care; Injection of therapeutic agent; Interneurons; K-Series Research Career Programs; Label; Life; Medical; Membrane; Modeling; Neonatal; Neurologic; Neurons; Oocytes; Operative Surgical Procedures; Outcome; Pathology; Patients; Pattern; Pharmaceutical Preparations; Play; Population; Pregnancy; Premature Infant; Preparation; Property; Pyramidal Cells; Relative (related person); Resected; Resistance; Role; Sedation procedure; Seizures; Specimen; Techniques; Therapeutic; Time; Western Blotting; Xenopus oocyte; age group; aged; barbituric acid salt; base; brain tissue; cell type; clinical application; early childhood; gamma-Aminobutyric Acid; improved; innovation; neonate; neurosteroids; receptor; sex; voltage clamp

DESCRIPTION (provided by applicant): Seizures in infants and neonates are common, are often resistant to currently used treatments, and can have devastating outcomes. The most frequently used anticonvulsant medications in this age group, the barbiturates and the benzodiazepines, act by enhancement of current through neuronal GABAA receptors. The focus of the current study is to characterize the development of human cortical GABAergic inhibition from late gestation through early childhood, and further to assess how this development is disrupted by conditions causing seizures in this age group. The underlying hypothesis of this proposal is that immature patterns of GABAA receptor subunit and cation-chloride cotransporter expression in human cortex result in pharmacologic properties predictive of low efficacy or even harmful consequences of the use of GABAergic agents in the treatment of premature infants, neonates, and young children. The Specific Aims of this proposal include: 1) Define the time course of the developmental maturation of human cortical GABAA receptor subunit and cation-chloride cotransporter expression, and assess abnormalities in expression related to early-life seizures due to malformations of cortical development. This aim will be achieved through the use of quantitative Western blot analysis with infrared fluorescence detection. Frozen postmortem and surgical cortical specimens will be collected from control infants at 20 weeks gestation through 3 years of age, as well as similarly-aged infants with seizures due to glioneuronal malformations of cortical development or migrational disorders. In addition, a clinical database will be constructed and correlated with our experimental data to assess whether variables that have been shown to modulate receptor or transporter expression in experimental epilepsy models might also play a significant role in our human epilepsy population. 2) Determine the functional and pharmacological consequences of developmental and seizure-associated changes in GABAA receptor subunit and cation-chloride cotransporter expression in human cortex. An innovative experimental paradigm will be utilized which allows electrophysiological analysis of GABAA receptors from frozen human brain tissue resulting in "microtransplantation" of native human receptors into the Xenopus oocyte plasma membrane. 3) Analyze alterations in the cellular distribution of GABAA receptor subunits and chloride transporters in human cortex related to early-life seizures. Funding from this Career Development Award will permit the PI to acquire expertise in the techniques of fluorescence immunohistochemistry and in situ hybridization to determine the cortical cell populations exhibiting changes in GABAergic properties during both normal human development and its disruption by seizures due to cortical malformations. Information gained as a result of this study could have direct clinical applications that produce improved medical and neurologic care of infants and neonates. PUBLIC HEALTH RELEVANCE: Currently used treatments for neonatal seizures that target neuronal GABAA receptors are often ineffective and, based on data from animal models, may actually be detrimental. The goal of this proposal is to characterize the development of human cortical GABAergic inhibition from late gestation through early childhood, and further to assess how this development is disrupted by conditions causing seizures in this age group. Results from this study may encourage the reconsideration of the use of GABAergic medications in the treatment of seizures or sedation in infants and neonates, and also suggest better therapeutic alternatives.

描述（由申请人提供）：婴儿和新生儿的癫痫发作常见，通常对当前使用的治疗具有抵抗力，并且可能具有毁灭性的结果。该年龄组最常用的抗惊厥药物是巴比妥类药物和苯二氮卓类药物，通过通过神经元GABAA受体增强电流来起作用。当前研究的重点是表征从妊娠到幼儿期从妊娠到幼儿的人皮层GABA能抑制的发展，并进一步评估该年龄段引起癫痫发作的条件如何破坏这种发展。该提案的基本假设是，人类皮质中GABAA受体亚基和阳离子 - 氯化物共转移蛋白的表达的未成熟模式导致了药理学特性，可预测使用GABAergic药物在治疗中的早产儿，新生儿和新生儿和年轻儿童中使用GABAergic药物的低功效甚至有害后果。该提案的具体目的包括：1）定义人皮质GABAA受体亚基和阳离子 - 氯化物共转运蛋白表达的发育成熟的时间过程，并评估由于皮质发育的畸形而引起的与早期癫痫发作有关的表达异常。通过使用定量蛋白质印迹分析和红外荧光检测，将实现此目标。将在20周妊娠到3岁的对照婴儿中收集验证后和手术皮质标本，以及由于皮质发育或移民疾病的神经神经元畸形而导致的类似年龄的婴儿。此外，将构建临床数据库并与我们的实验数据相关联，以评估在实验性癫痫模型中调节受体或转运蛋白表达的变量是否也可能在我们的人类癫痫群中起重要作用。 2）确定人皮层中GABAA受体亚基和阳离子 - 氯化物共转运蛋白的发育和癫痫相关变化的功能和药理后果。将利用创新的实验范式，该范例可以从冷冻人脑组织中对GABAA受体进行电生理分析，从而导致本地人类受体“微移植”到Xenopus卵母细胞质膜中。 3）分析与早期癫痫发作有关的人皮层中GABAA受体亚基和氯化物转运蛋白的细胞分布的改变。该职业发展奖的资金将允许PI获得荧光免疫组织化学技术和原位杂交技术的专业知识，以确定在正常人类发育期间及其因皮质畸形而导致的癫痫发育中的GABAergic特性变化的皮质细胞群体。由于这项研究而获得的信息可能具有直接的临床应用，从而可以改善婴儿和新生儿的医学和神经保健。 公共卫生相关性：目前对靶向神经元GABAA受体的新生儿癫痫发作的治疗方法通常无效，并且根据动物模型的数据，实际上可能是有害的。该提案的目的是表征从妊娠到幼儿期从妊娠期到幼儿的人类皮质GABA能抑制的发展，并进一步评估该发展如何被该年龄段引起癫痫发作的疾病破坏。这项研究的结果可能鼓励重新考虑使用GABA能药物在婴儿和新生儿的癫痫发作或镇静治疗中的使用，也提出更好的治疗替代方法。