Projection Specific Modulation of Neural Activity with A Non-genetic Method

项目摘要 在精神病学和神经学中，有许多基于异常回路的衰弱障碍，我们确实是这样做的。 没有适当的治疗方法。光遗传学和病毒技术的最新发展 证明了调节大脑中特定投射的神经活动能够拯救 行为缺陷，包括与抑郁、自闭症和焦虑相关的行为缺陷。然而，这种方法 需要通过病毒转导对神经元进行基因改造，这为临床带来了重大障碍 出于安全方面的考虑，应用程序。此外，目前的投射靶向神经调制方法都使用 可见光，限制了光的穿透深度和独立通道的数量 可用于记录和调节神经活动。在这里，我想提出一种非遗传方法 用于对行为自由的哺乳动物的神经活动进行投影特异性调节。此方法将使用 金纳米棒，一种近红外(NIR)吸收剂和用于神经调制的热产生。我们的预赛 结果表明，金纳米棒被神经元胞体或轴突终末内化。 通过神经轴突逆行/顺行运输，并足以调节神经活动 轴突在体外转运后的近红外光。这项工作的目的是继续发展这种方法，从 从体外到体内，这将是其未来临床翻译的关键。在目标1中，我将确定 用荧光表征脑片研究金纳米棒体内内化和轴突转运 显微镜和电子显微镜。清晰度将被用来可视化整个纳米颗粒 投影。还将研究金纳米棒的体内毒性。在目标2中，我将确定 膜片钳对神经活动的光热调制，特别是离子和离子通道的类型 在调制过程中涉及。我还将验证体内神经调制的传导 用纤维光度法测量活度。在目标3中，我将考察投射特异性调制的有效性。 用我们开发的金纳米棒方法在与奖励和焦虑相关的模型电路中研究啮齿动物的行为。 这些目标的完成将导致第一个用于投射靶向调制的非遗传方法 神经活动。这种方法将补充光发生神经调制和钙成像 正交近红外通道，由于它的非对称性，将为临床治疗应用提供更好的机会 遗传性和非病毒性。这项工作将在一个咨询成员的团队下完成，该团队由一名 神经学家和纳米材料专家的良好平衡：卡尔·戴瑟罗斯博士、萨姆·甘比尔博士、洪杰博士 戴博士、范阳博士和塔莉亚·勒纳博士。在项目完成后，我将精通各种 活体技术，如光遗传学、纤维测光、清晰度和啮齿动物行为实验。

Project Summary In psychiatry and neurology, there are many debilitating disorders based on aberrant circuits for which we do not have adequate treatment methods. Recent developments in optogenetics and viral technology have demonstrated that modulating the neural activity of specific projections in the brain is capable of rescuing behavioral deficits, including those relevant to depression, autism and anxiety. However, this approach requires genetic modification of neurons via viral transduction, which introduces a significant barrier for clinical applications due to safety concerns. Also, the current projection-targeted neural modulation methods all use visible light, limiting both the light penetration depth and the number of independent channels neuroscientists can use for recording and modulating neural activity. Here, I would like to propose a non-genetic method for projection-specific modulation of neural activity in freely behaving mammals. This approach will use gold nanorods, a near-infrared (NIR) absorber and heat generation for neural modulations. Our preliminary results have demonstrated that gold nanorods are internalized by neuron soma or axon terminals, are transported retrograde/anterograde through neural axons and are sufficient to modulate neural activity under NIR light after axon transport in vitro. The aim of this work is to continue the development of this approach from in vitro to in vivo, which will be crucial for its future clinical translation. In Aim 1, I will determine the internalization and axon transport of gold nanorods in vivo by characterizing brain slices with fluorescence microscopy and electron microscopy. CLARITY will be used to visualize the nanoparticles in the whole projection. The in vivo toxicity of gold nanorods will also be studied. In Aim 2, I will determine the mechanism of photothermal modulation of neural activity by patching clamp, particularly the types of ions and ion channels involved during the modulation process. I will also verify the conductions for in vivo modulation of neural activity using fiber photometry. In Aim 3, I will examine the effectiveness of projection-specific modulation of rodent behaviors with our developed gold nanorod methods in model circuits related to reward and anxiety. The completion of the aims will result in the first non-genetic method for projection-targeted modulation of neural activity. This method will complement optogenetic neural modulation and calcium imaging with an orthogonal NIR channel and will present a better opportunity for clinical therapeutic applications due to its non- genetic and non-viral nature. The work will be accomplished under a team of advisory members consisting of a good balance of neuroscientists and nanomaterial experts: Dr. Karl Deisseroth, Dr. Sam Gambhir, Dr. Hongjie Dai, Dr. Fan Yang and Dr. Talia Lerner. After the completion of the project, I will become proficient in various in vivo techniques, such as optogenetics, fiber photometry, CLARITY and rodent behavior experiments.