Deciphering the GABA neuron alterations in schizophrenia

破译精神分裂症中 GABA 神经元的改变

基本信息

批准号：
10545717
负责人：
KENNETH N FISH
金额：
$ 48.58万
依托单位：
UNIVERSITY OF PITTSBURGH AT PITTSBURGH
依托单位国家：
美国
项目类别：
财政年份：
2019
资助国家：
美国
起止时间：
2019-03-15 至 2024-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/10545717
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 Specificity Testing Transcript calbindin calretinin cell type cohort differential expression extracellular gamma-Aminobutyric Acid gene product genetic variant hippocampal pyramidal neuron insight neural circuit neuronal cell body neuronal circuitry neurotransmission novel programs promoter sensor therapeutic target transcriptome transcriptome sequencing

项目摘要

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的结果改变神经回路发展轨迹的危险因素。尽管这种病因多样性，但改变了在GABA中，神经元是SZ的高度保守特征，大量数据表明了这些改变导致该疾病的认知功能障碍。 GABA神经传递在很大程度上取决于GAD67。 SZ受试者PFC中的许多GABA神经元表达了正常水平的GAD67 mRNA，但该转录本是该疾病中的PFC GABA神经元的30-50％无法检测到。受影响的GABA神经元的身份在很大程度上未知。 GABA神经元的转录唯一亚型（TUS）独特靶向不同锥体神经元（PN）合奏，使它们能够强大地调节某些脑部范围的网络和行为。因此，了解SZ中受影响的GABA TU的身份以及GAD67的机制仅在某些GABA TU中出现的mRNA缺陷对于向机械理解发展至关重要疾病的皮质回路改变。为了满足这些需求，提出了以下目标： AIM 1。分别量化SOMA和轴突末端中的GAD67 mRNA和蛋白质水平 SZ中的Gaba Tus。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 TU的标记，捕获所有GABA神经元的95％。多路复用荧光原位杂交（FISH）用于量化PFC中这些TU内的GAD67 mRNA水平匹配的SZ和对照（CON）受试者（队列1）。在同一受试者中，多标签免疫组织化学用于量化不同GABA TU的轴突末端中的GAD67蛋白水平。 GAD67 mRNA SZ中的赤字预计将仅限于特定的GABA TU，后者具有较低的末端GAD67蛋白水平。目标2。确定特定于SZ疾病过程的TU的改变模式。一些皮质GABA神经元的改变，包括较低水平的GAD67，似乎在SZ上共享双极疾病（BP）和主要抑郁症（MDD），而其他疾病则没有。目标1的研究1 在匹配的SZ，BP，MDD和CON受试者的全新第二个队列中进行。 SZ，BP和MDD是每个人都有一个独特的星座，是受影响的GABA神经元亚型相对于彼此的独特星座。 AIM 3。在SZ和CON受试者中对GABA TUS进行转录组测序。在队列1受试者中，每种GABA TU的单个神经元通过鱼类鉴定，使用激光显微解剖收集，合并并进行转录组测序。在SZ中，预计受影响的Gaba Tus将共享差异表达的基因是已知调节GAD67表达的途径的组成部分。通过识别受影响的GABA TU的SZ特异性星座并评估其转录组谱，这些研究将为TUS特异性GABA神经元的未来机械测试提供基本信息模型系统中的电路功能障碍和开发GABA TUS的治疗靶标。