Mitochondria and anesthetic-induced developmental neurotoxicity

项目摘要 数以百万计的儿童接受全身麻醉（GA）的外科手术。来自人类的新证据 流行病学和动物研究表明，短效全身麻醉药可引起急性脑 损伤，导致长期的认知缺陷和行为问题。2016年，美国食品和药物管理局 政府发布了关于GA暴露在年龄以下儿童中的潜在神经毒性影响的警告 三.由于GA的使用是许多手术所必需的，因此避免GA通常是不可能的。因此，了解如何 麻醉剂诱导的神经毒性在公共卫生中至关重要，特别是有效的 可以开发神经保护策略。一个很有前途的研究领域是线粒体， 神经元具有高能量需求，它们特别容易因功能失调而受伤和死亡。 线粒体然而，尽管对麻醉剂诱导的发育神经毒性进行了广泛的研究， （AIDN）在过去几十年中完成，线粒体损伤导致神经元损伤的机制 信号失调和细胞死亡仍不清楚。线粒体损伤与肝硬化的关系 麻醉剂诱导的长期行为异常尚未被研究。解决上述 gap，在我们的初步研究中，我们调查并发现麻醉剂对线粒体是有毒的， 开发小鼠和人类的脑细胞。我们的数据还表明，失调的非- 麻醉诱导的线粒体功能受损中的编码RNA。因此，该计划的总体目标 是通过研究线粒体的功能，继续填补麻醉剂无毒性方面线粒体知识的差距。 线粒体在AIDN中的新的调节分子机制以及发展神经保护作用 针对线粒体的方法。根据我们实验室最近的研究和初步发现， 拟议的计划将集中在以下三个独立的研究领域：1）确定功能， 麻醉诱导的认知功能障碍中线粒体信号传导的脑细胞类型特异性机制， 异常行为2)描述新的转录后调控机制， 在AIDN中调节信号传导和功能。3)探讨小分子药物对艾滋病肾病的神经保护作用。 我们将使用转基因小鼠模型和类似的人类诱导模型进行这些研究。 通过CRISPR-Cas9基因编辑获得的多能干细胞模型。此外，该计划将使用 创新的，尖端的实验神经科学工具，无偏见的多组学方法（例如，基因增益- 多光子真实的时间成像、单细胞RNA测序和高通量分析 神经元活动）。这些研究将有助于更好地理解GA驱动的线粒体 功能障碍，这可能会导致有效的治疗方法，预防艾滋病在幼儿。

PROJECT SUMMARY Millions of children receive general anesthetics (GAs) for surgical procedures. Emerging evidence from human epidemiologic and animal studies suggest that short acting general anesthetic drugs can cause acute brain injury, leading to long-term cognitive defects and behavioral problems. In 2016, the US Food and Drug Administration issued a warning about the potential neurotoxic effects of GA exposure in children under age three. As GA use is necessary for many surgeries, avoidance is often impossible. Thus, understanding how anesthetics induce neurotoxicity is of critical importance in public health, especially so that effective neuroprotective strategies can be developed. One promising area of investigation is mitochondria -- as neurons have high energy requirements, they are especially vulnerable to injury and death from dysfunctional mitochondria. However, despite the extensive research of anesthetic-induced developmental neurotoxicity (AIDN) done during the last decades, mechanisms by which mitochondrial impairment leads to neuronal signaling deregulation and cell death remain unclear. Causative relationship between mitochondrial injury and anesthetic-induced long-term behavioral abnormalities has not been explored. To address the aforementioned gap, in our preliminary studies we investigated and found that anesthetics were toxic to mitochondria in developing mouse and human brain cells. Our data also suggest the regulative function of dysregulated non- coding RNAs in anesthetic-induced impaired mitochondrial function. Thus, the overarching goal of this program is to continue to fill the gap of mitochondrial knowledge in anesthetic nontoxicity by investigating the functions and novel regulatory molecular mechanisms of mitochondria in AIDN as well as developing neuroprotective approaches targeting mitochondria. Extending upon our lab's recent research and preliminary findings, our proposed program will focus on the following three independent research areas: 1) Determine functions and brain cell type-specific mechanisms of mitochondrial signaling in anesthetic-induced cognitive dysfunction and abnormal behaviors. 2) Delineate novel posttranscriptional regulation mechanisms by which mitochondrial signaling and functions are regulated in AIDN. 3) Investigate neuroprotective effect of small molecules in AIDN. We will conduct these investigations using both transgenic mouse models and similar human induced pluripotent stem cell models obtained via CRISPR-Cas9 gene editing. Furthermore, this program will use innovative, cutting-edge experimental neuroscience tools, unbiased multi-omic approaches (e.g., gene gain- and loss-of function, multiphoton real time imaging, single-cell RNA sequencing, and high-throughput analysis of neuronal activities). The proposed studies will facilitate a better understanding of GA-driven mitochondrial dysfunction, which may lead to effective therapeutics for preventing AIDN in young children.