Deciphering the GABA neuron alterations in schizophrenia

破译精神分裂症中 GABA 神经元的改变

• 批准号: 9890003
• 负责人: KENNETH N FISH
• 金额: $ 38.15万
• 依托单位: UNIVERSITY OF PITTSBURGH AT PITTSBURGH
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-03-15 至 2023-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9890003
• 关键词: Affect; Amygdaloid structure; Autopsy; Behavior; Biological Models; Bipolar Disorder; Brain; Cells; Cholecystokinin; Cognitive deficits; Complex; Confocal Microscopy; Data; Development; Diagnosis; Disease; Environmental Risk Factor; Enzymes; Etiology; Fluorescent in Situ Hybridization; Foundations; Functional disorder; Future; Gene Expression; Genes; Genetic Transcription; HDAC1 gene; Human; Immunohistochemistry; Impaired cognition; Individual; Label; Lasers; Learning; Major Depressive Disorder; Messenger RNA; Methylation; Microdissection; Mus; Myoepithelial cell; Neurons; Parvalbumins; Pathway interactions; Pattern; Prefrontal Cortex; Presynaptic Terminals; Primates; Process; Proteins; Reporting; Schizophrenia; Signal Pathway; Signal Transduction; Testing; Transcript; base; calbindin; calretinin; cell type; cohort; differential expression; disorder control; extracellular; gamma-Aminobutyric Acid; gene product; genetic variant; hippocampal pyramidal neuron; insight; neural circuit; neuronal cell body; neurotransmission; novel; promoter; therapeutic target; transcriptome; transcriptome sequencing

PROJECT SUMMARY Schizophrenia (SZ) results from the complex interplay of genetic variants affecting liability and environmental risk factors that alter developmental trajectories of neural circuits. Despite this etiological diversity, alterations in GABA neurons are a highly conserved feature of SZ and substantial data suggest these alterations contribute to cognitive dysfunction in the disorder. GABA neurotransmission is heavily dependent on GAD67. Many GABA neurons in the PFC of SZ subjects express normal levels of GAD67 mRNA, but this transcript is not detectable in 30-50% of PFC GABA neurons in the disorder. The identities of the affected GABA neurons are largely unknown. Transcriptionally-unique subtypes (TUS) of GABA neurons uniquely target distinct pyramidal neuron (PN) ensembles, allowing them to powerfully modulate certain brain-wide networks and behaviors. Thus, knowing the identity of the affected GABA TUS in SZ and the mechanisms underlying GAD67 mRNA deficits occurring in only some GABA TUS is essential for moving towards a mechanistic understanding of the cortical circuitry alterations in the illness. To meet these needs, the following Aims are proposed: Aim 1. Quantify GAD67 mRNA and protein levels in the soma and axon terminals, respectively, of GABA TUS in SZ. Information from profiling studies of GABA neurons in mice, was used to identify mRNA markers that distinguish 10 GABA TUS in human PFC, which capture >95% of all GABA neurons. Multiplex fluorescence in situ hybridization (FISH) is used to quantify GAD67 mRNA levels within these TUS in the PFC of matched SZ and control (CON) subjects (Cohort 1). In the same subjects, multi-label immunohistochemistry is used to quantify GAD67 protein levels in the axon terminals of the different GABA TUS. The GAD67 mRNA deficit in SZ is predict to be restricted to specific GABA TUS, which have lower terminal GAD67 protein levels. Aim 2. Determine the pattern of altered TUS that is specific to the disease process of SZ. Some alterations in cortical GABA neurons, including lower levels of GAD67, seem to be shared across SZ, bipolar disorder (BP), and major depressive disorder (MDD), whereas those of others are not. The studies of Aim 1 are conducted in an all new second cohort of matched SZ, BP, MDD and CON subjects. SZ, BP, and MDD are predicted to each have a unique constellation of affected GABA neuron subtypes relative to each other. Aim 3. Perform transcriptome sequencing of GABA TUS in SZ and CON subjects. In Cohort 1 subjects, individual neurons of each GABA TUS are identified by FISH, collected using laser microdissection, pooled and subjected to transcriptome sequencing. In SZ, the affected GABA TUS are predicted to share a pattern of differentially-expressed genes that are components of pathways known to regulate GAD67 expression. By identifying the SZ-specific constellation of affected GABA TUS and assessing their transcriptome profile, these studies will provide essential information for future mechanistic tests of TUS-specific GABA neuron circuit dysfunction in model systems and developing therapeutic targets of GABA TUS.

项目摘要 精神分裂症（SZ）是由影响责任和环境的遗传变异的复杂相互作用引起的。 改变神经回路发育轨迹的风险因素。尽管病因多样， 在GABA神经元中的变化是SZ的高度保守特征，大量数据表明这些变化 会导致认知功能障碍GABA神经传递严重依赖于GAD 67。 SZ受试者PFC中的许多GABA神经元表达正常水平的GAD 67 mRNA，但该转录本在正常水平表达。 在疾病中的30-50%的PFC GABA神经元中未检测到。受影响的GABA神经元的身份 在很大程度上是未知的。GABA神经元的转录独特亚型（TUS）独特地靶向不同的 锥体神经元（PN）集合，使它们能够有力地调节某些全脑网络， 行为。因此，了解SZ中受影响的GABA TUS的身份和GAD 67的潜在机制， 仅在某些GABA TUS中发生的mRNA缺陷对于理解机制至关重要 大脑皮层回路的改变为满足这些需要，提出了以下目标： 目标1.分别定量GAD 67 mRNA和蛋白质水平在索马和轴突终末， GABA TUS在SZ.来自小鼠GABA神经元的分析研究的信息用于鉴定mRNA 在人类PFC中区分10个GABA TUS的标记物，其捕获>95%的所有GABA神经元。复用 荧光原位杂交（FISH）用于定量PFC中这些TUS内的GAD 67 mRNA水平 匹配的SZ和对照（CON）受试者（队列1）。在同一受试者中，多标记免疫组化 用于定量不同GABA TUS的轴突末端中的GAD 67蛋白水平。GAD67 mRNA 预测SZ缺陷限于特定的GABA TUS，其具有较低的末端GAD 67蛋白水平。 目标2.确定特定于SZ疾病过程的TUS改变模式。一些 皮质GABA神经元的改变，包括GAD 67水平降低，似乎在SZ、双极和双极之间共享。 抑郁症（英语：Major depression disorder）是一种抑郁症，而其他人则不是。目标1的研究 在匹配的SZ、BP、MDD和CON受试者的全新第二队列中进行。SZ、BP和MDD是 预测每个具有相对于彼此的受影响GABA神经元亚型的独特星座。 目标3.在SZ和CON受试者中进行GABA TUS的转录组测序。在队列1受试者中， 通过FISH鉴定每个GABA TUS的单个神经元，使用激光显微切割收集，合并 并进行转录组测序。在深圳，预计受影响的GABA TUS具有以下模式： 差异表达基因是已知调节GAD 67表达的途径的组分。 通过鉴定受影响的GABA TUS的SZ特异性星座并评估其转录组谱， 这些研究将为将来TUS特异性GABA神经元的机制测试提供必要的信息 电路功能障碍的模型系统和开发GABA TUS的治疗目标。