Targeting Mitochondrial Function to Develop Novel Therapies for Neurodevelopmental Disorders

摘要 我们将确定潜在的新药理学疗法，旨在改善一类线粒体功能 大脑皮层神经元被认为在多种神经发育障碍中受到损害。我们有 显示 LgDel 小鼠 2/3 层投射神经元 (PN) 中的线粒体代谢受到破坏 22q11.2 缺失综合征模型，一种综合征性神经发育障碍。我们还展示了 这种破坏显然解释了关联皮质连接的数量差异 与 LgDel 小鼠的认知行为缺陷相关。最后，我们证明了一种自由基清除剂 影响线粒体功能的 N-乙酰半胱氨酸 (NAC) 可以逆转这些分子、细胞和 行为缺陷。我们现在将评估多种线粒体靶向药理学的能力 化合物以及已知的线粒体靶向药物，可调节 LgDel Layer 2/3 PN 线粒体 代谢及其对 2/3 层 PN 稳态的影响。在具体目标 1 中，我们将评估化合物 使用安捷伦 Seahorse 代谢分析仪进行经过验证的均质层 2/3 PN 体外测定中的活性 测量线粒体功能的关键方面。恢复 LgDel 线粒体的候选化合物 WT 功能障碍，而不破坏 WT 线粒体功能，将进一步验证其能力 减少异常线粒体活性氧 (ROS) 水平并恢复树突和轴突 LgDel 层 2/3 PN 的增长。为机械精度提供额外的解释分辨率 这些化合物，在特定目标 2 中，我们将进行 LgDel 与 WT 的平行转录组比较 体外第 2/3 层 PN，用于识别转录调控因线粒体而改变的途径 神经发育病理学针对的正在发育的第 2/3 层 PN 的功能障碍和生长减少。 我们将进一步将此数据与经 NAC 处理的 LgDel 层 2/3 PN 的转录组概况进行对比，其 我们之前已经证明了代谢和生长恢复活性。因此，本研究中鉴定的化合物 筛选将验证特异性、目标细胞活性，并置于差异化监管的背景下 对线粒体功能改变敏感的转录途径。这些途径是减少的基础 神经元生长有助于神经发育皮质回路病理学。因此，我们的实验确定 进一步开发基于线粒体的疗法和分子机制的潜在候选者 合理设计精确靶向新药以纠正分子和细胞病理学的框架 与多种神经发育障碍中皮质神经元和回路受损有关。

ABSTRACT We will identify potential new pharmacological therapies targeted to improve mitochondrial function in a class of cerebral cortical neurons thought to be compromised in multiple neurodevelopmental disorders. We have shown that mitochondrial metabolism is disrupted in layer 2/3 Projection Neurons (PNs) in the LgDel mouse model of 22q11.2 Deletion Syndrome, a syndromic neurodevelopmental disorder. We have also demonstrated that this disruption apparently accounts for quantitative differences in association cortical connectivity correlated with cognitive behavioral deficits in LgDel mice. Finally, we showed that a free radical scavenger that influences mitochondrial function, N-acetyl cysteine (NAC), can reverse these molecular, cellular and behavioral deficits. We will now assess the capacity of multiple mitochondrial targeted pharmacological compounds, as well as known mitochondria-targeted drugs, to modulate LgDel Layer 2/3 PN mitochondrial metabolism and its influences on layer 2/3 PN homeostasis. In Specific Aim 1, we will evaluate compound activity in a validated, homogeneous layer 2/3 PN in vitro assay using the Agilent Seahorse Metabolic Analyzer to measure key aspects of mitochondrial function. Candidate compounds that restore LgDel mitochondrial dysfunction toward WT, without disrupting WT mitochondrial function, will be further validated for their capacity to diminish aberrant mitochondrial reactive oxygen species (ROS) levels and restore dendritic and axonal growth in LgDel layer 2/3 PNs. To provide additional interpretative resolution of the mechanistic precision of these compounds, in Specific Aim 2 we will perform a parallel transcriptome comparison of LgDel versus WT Layer 2/3 PNs in vitro to identify pathways whose transcriptional regulation is altered due to mitochondrial dysfunction and diminished growth in developing Layer 2/3 PNs targeted by neurodevelopmental pathology. We will further contrast this data with the transcriptome profile of LgDel layer 2/3 PNs treated with NAC, whose metabolic and growth-restoring activity we have previously demonstrated. Thus, compounds identified in this screen will be validated for specificity, targeted cellular activity, and placed in context of differentially regulated transcriptional pathways sensitive to altered mitochondrial function. These pathways underlie diminished neuron growth that contributes to neurodevelopmental cortical circuit pathology. Thus, our experiments identify potential candidates for further development of mitochondria-based therapies and a molecular mechanistic framework for rational design of precisely targeted new drugs to correct molecular and cellular pathology associated with cortical neuron and circuits compromised in multiple neurodevelopmental disorders.