Astrocytes contribution to tuberous sclerosis pathology

星形胶质细胞对结节性硬化症病理学的贡献

• 批准号: 8995715
• 负责人: Angelique Bordey
• 金额: $ 24.98万
• 依托单位: YALE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-02-01 至 2017-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8995715
• 关键词: Address; Alleles; Alzheimer' s Disease; Apolipoprotein E; Apolipoproteins; Astrocytes; Autistic Disorder; Axon; Behavior; Brain; Cancer Center; Cerebrospinal Fluid; Cholesterol; Complex; Conditioned Culture Media; Data; Defect; Development; Diagnosis; Disease; Electroporation; Exhibits; FRAP1 gene; Foundations; Future; Genetic Transcription; Glial Fibrillary Acidic Protein; Grant; Health; Human; Hyperactive behavior; Immunoblotting; Impairment; In Vitro; Individual; Infant; Investigation; Label; Length; Mendelian disorder; Mus; Mutation; Neurodevelopmental Disorder; Neuroglia; Neurologic; Neurons; Pathology; Patients; Pattern; Play; Population; Proteomics; Role; Seizures; Social Behavior; Symptoms; TSC1 gene; TSC2 gene; Testing; Therapeutic; Time; Transgenic Mice; Tuberous Sclerosis; Tuberous sclerosis protein complex; Validation; Work; autism spectrum disorder; axon growth; base; brain abnormalities; cancer proteomics; in utero; in vivo; macroglia; neural circuit; neuron development; neuropsychological; novel; novel strategies; postnatal; premature; promoter; recombinase; research study; trait

 DESCRIPTION (provided by applicant): The precise timing of formation and length of axonal connectivity in the developing brain is essential for proper neural circuit connectivity and function. As such, alterations in axonal connectivity are thought to contribute to neuropsychological impairments in autism spectrum disorder including monogenic disorders associated with autism such as tuberous sclerosis complex (TSC). TSC individuals express a silencing mutation in one TSC1 or TSC2 allele leading to hyperactivity of the mammalian target of rapamycin complex 1 and 40-60% of these individuals display mild to severe autistic traits and other neuropsychological problems that are independent of seizures or gross brain abnormalities. In TSC as well as other disorders associated with autism, the mechanisms leading to altered axonal connectivity remain unclear. One possible mechanism that remains unexplored is the contribution of astrocytes to abnormal axonal growth in TSC. Astrocytes are a subtype of macroglia that play a critical role in regulating neuronal development including axon elongation. Here, we thus propose to test the hypothesis that Tsc1+/- astrocytes contribute to increased axonal growth in TSC. We have two aims. The first aim proposes to assess whether Tsc1+/- astrocytes accelerate axon growth and increase axonal patterning. Using iTRAQ (isobaric tags for relative and absolute quantitation)-based quantitative proteomics, we identified several molecules altered in Tsc1+/- astrocyte-conditioned medium, such as apolipoprotein E (apoE) that is a good candidate for controlling axon elongation. The second aim proposes to examine whether reduced apoE levels in Tsc1+/- astrocytes contributes to abnormal axon growth. To address our hypothesis, we will use purified cultures of astrocytes and neurons as well as in vivo approaches using conditional transgenic mice to delete one allele of Tsc1 selectively in astrocytes combined with in utero electroporation to label selective neuronal populations or single cortical neurons for axon tracing.

 描述（由申请人提供）：发育中的大脑中轴突连接形成的精确时间和长度对于适当的神经回路连接和功能至关重要。因此，轴突连接的改变被认为有助于自闭症谱系障碍中的神经心理学损伤，包括与自闭症相关的单基因障碍，如结节性硬化症（TSC）。TSC个体在一个TSC 1或TSC 2等位基因中表达沉默突变，导致雷帕霉素复合物1的哺乳动物靶标的过度活跃，并且这些个体中的40-60%表现出轻度至重度自闭症特征和其他神经心理学问题，这些问题与癫痫发作或严重脑异常无关。在TSC以及其他与自闭症相关的疾病中，导致轴突连接改变的机制仍不清楚。一个可能的机制是星形胶质细胞对TSC中异常轴突生长的贡献。星形胶质细胞是大胶质细胞的一种亚型，在调节神经元发育（包括轴突伸长）中发挥关键作用。在这里，我们因此建议测试的假设，Tsc 1 +/-星形胶质细胞有助于增加轴突生长TSC。我们有两个目标。第一个目标是评估Tsc 1 +/-星形胶质细胞是否加速轴突生长并增加轴突图案化。使用iTRAQ（isobaric tags for relative and absolute quantitation，相对和绝对定量的同量异序标记）定量蛋白质组学，我们确定了 在Tsc 1 +/-星形胶质细胞条件培养基中改变的几种分子，例如载脂蛋白E（apoE），它是控制轴突延伸的良好候选者。第二个目的是研究Tsc 1 +/-星形胶质细胞中apoE水平的降低是否有助于异常轴突生长。为了解决我们的假设，我们将使用纯化培养的星形胶质细胞和神经元，以及在体内的方法，使用条件转基因小鼠删除一个等位基因的Tsc 1选择性在星形胶质细胞结合在子宫内电穿孔标记选择性神经元群体或单个皮质神经元轴突追踪。