Roles of hemocytes and bioactive lipids in the modulation of neuronal excitability and seizure behavior in Drosophila voltage-gated sodium channel mutants

血细胞和生物活性脂质在果蝇电压门控钠通道突变体神经元兴奋性和癫痫行为调节中的作用

基本信息

批准号：
10559686
负责人：
TOSHIHIRO KITAMOTO
金额：
$ 19.31万
依托单位：
UNIVERSITY OF IOWA
依托单位国家：
美国
项目类别：
财政年份：
2022
资助国家：
美国
起止时间：
2022-02-15 至 2025-01-31
项目状态：
未结题

项目摘要

PROJECT SUMMARY Local and systemic interactions between the nervous system and immune system play important roles in various physiological and pathological processes. The long-term goal of this project is to obtain a fundamental understanding of how neuroimmune communications contribute to the regulation of neural development, physiology, and behavior using an experimental model organism Drosophila melanogaster possessing the evolutionarily conserved innate immune system. The overall objective in this application is to reveal the roles and mechanisms of functional interactions between innate immune cells and the central nervous system in the modulation of neuronal excitability and behavioral hyperactivity in seizure-prone fly voltage-gated sodium (Nav) channel mutant, paraShu. The project is based on intriguing findings that: 1) paraShu adult seizure severity is significantly suppressed by diet supplemented with -3 polyunsaturated fatty acids (PUFAs) -linolenic acid (ALA); 2) hemocyte (macrophage-like blood cell)-specific knockdown of GstS1, a fly ortholog of mammalian prostaglandin D synthase, mimics the effect of dietary ALA; and 3) both dietary ALA and GstS1 knockdown are effective during development to suppress seizures in adult mutants. The central hypothesis is that the severity of adult paraShu is modulated through neural development by the action of innate immune cells in the biological processes involving bioactive lipid mediators. Two specific aims will be pursued to investigate the hypothesis: 1) Define the roles of hemocytes in modulation of neuronal excitability and behavioral hyperactivity in paraShu mutants; and 2) Identify genes and signaling pathways involved in hemocyte-dependent modulation of adult seizures. For the first aim, hemocyte functions will be genetically perturbed and the effects on neural development, electrophysiological properties, and seizure behavior will be examined in the presence or absence of phenotypic modifiers using freely moving or tethered behaving adult flies as well as dissociated primary neuronal cultures prepared from mutant larval brains. For the second aim, a candidate gene approach will be used to identify genes involved in putative lipid signaling processes, and lipidomics analysis will be carried out to determine the changes in oxylipins, lipid mediators produced from PUFAs, in the mutants in the presence or absence of phenotypic modifiers. The proposed multidisciplinary research is expected to reveal the roles of hemocytes in the diet-dependent modulation of neuronal excitability and behavioral seizures in Nav channel mutants, and provide novel genetic and molecular insights into the largely unexplored lipid signaling pathways that play important roles in the modulation of genetically predisposed neurological phenotypes. The project is scientifically and clinically significant because it will lead to a deeper appreciation of the plastic and interactive nature of the nervous system controlled by the immune system, and is expected to provide valuable insights into future strategies to prevent and treat nervous system disorders associated with aberrant immune function.

项目概要神经系统和免疫系统之间的局部和全身相互作用在该项目的长期目标是获得一个基本的生理和病理过程。了解神经免疫通讯如何促进神经发育的调节，使用具有实验模型生物果蝇的生理学和行为本申请的总体目标是揭示进化上保守的先天免疫系统的作用。以及先天免疫细胞与中枢神经系统之间功能相互作用的机制调节易癫痫蝇的神经兴奋性和行为过度活跃电压门控钠 (Nav) 通道突变体，paraShu 该项目基于以下有趣的发现：1）paraShu 成人癫痫发作的严重程度是补充 -3 多不饱和脂肪酸 (PUFA) -亚麻酸的饮食可显着抑制 (ALA)；2) 血细胞（巨噬细胞样血细胞）特异性敲低 GstS1（哺乳动物的果蝇直系同源物）前列腺素 D 合酶，模仿膳食 ALA 的作用；3) 膳食 ALA 和 GstS1 敲低均有效；在发育过程中有效抑制成年突变体的癫痫发作。成人 paraShu 的功能通过生物体内先天免疫细胞的作用通过神经发育进行调节。涉及生物活性脂质介质的过程将追求两个具体目标来研究该假设： 1）定义血细胞在调节paraShu神经元兴奋性和行为过度活跃中的作用突变体；2) 鉴定参与成人血细胞依赖性调节的基因和信号通路对于第一个目标，血细胞功能将受到遗传干扰并对神经产生影响。将在存在或存在的情况下检查发育、电生理特性和癫痫行为使用自由移动或拴系行为的成年果蝇以及解离的表型修饰剂的缺乏从突变幼虫大脑中制备原代神经培养物对于第二个目标，候选基因方法。将用于识别参与假定的脂质信号传导过程的基因，并且脂质组学分析将进行以确定突变体中氧脂质（由 PUFA 产生的脂质介质）的变化拟议的多学科研究有望揭示表型修饰剂的存在或不存在。血细胞在神经元兴奋性和行为癫痫发作的饮食依赖性调节中的作用通道突变体，并为很大程度上尚未探索的脂质信号传导提供新的遗传和分子见解在遗传易感神经表型的调节中发挥重要作用的途径。该项目具有科学和临床意义，因为它将导致人们对塑料和塑料有更深入的认识。神经系统与免疫系统的相互作用，并有望提供有价值的信息对预防和治疗与免疫异常相关的神经系统疾病的未来策略的见解功能。