Regeneration of auditory synaptic contacts using stem cell based approaches

使用基于干细胞的方法再生听觉突触接触

• 批准号: 9263690
• 负责人: Zhengqing Hu
• 金额: $ 32.3万
• 依托单位: WAYNE STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9263690
• 关键词: Address; Adult; Affinity; Animals; Astrocytes; Auditory; Auditory Evoked Potentials; Auditory system; Binding; Biological; Brain Stem; Cell Nucleus; Cells; Chemicals; Chronic; Cochlea; Cochlear nucleus; Coculture Techniques; Conditioned Culture Media; Cues; Data; Disease; Dose; Ensure; Future; Gene Expression; Generations; Glutamates; Goals; Hair Cells; Hearing; Human; Impairment; Implant; In Vitro; Knockout Mice; Labyrinth; Lead; Ligands; Measures; Mediating; Modeling; Mus; Natural regeneration; Neurites; Neurons; Ouabain; Pilot Projects; Play; Proteins; RNA Interference; Rattus; Research; Retinal Ganglion Cells; Role; Stem cells; Supplementation; Synapses; Testing; Thrombospondin 1; Vestibular ganglion; auditory pathway; base; deafness; gabapentin; hearing impairment; implantation; improved; in vivo; in vivo Model; in vivo regeneration; injured; inner ear diseases; knock-down; nerve stem cell; neurotrophic factor; neurotropin; overexpression; postnatal; public health relevance; receptor; restoration; sensory system; spiral ganglion; success; synaptogenesis

DESCRIPTION (provided by applicant): Spiral ganglion neurons (SGNs) and their synapses with the cochlear nucleus (CN) are important components of the auditory system that are impaired in a variety of auditory disorders. Currently, no biological approach exists to regenerate damaged SGNs. Our long-term aims of this proposal are to use stem cell (SC)-derived neurons to replace injured SGNs and regenerate afferent CN synapses that connect the cochlea to the brainstem. In this proposal, we will focus on afferent synapse generation between SC-derived glutamatergic neurons and CN neurons using in vitro and in vivo models. Regenerating the connections between hair cells and SC-derived neurons will be examined in a separate project. A recent study shows that implanted SC-derived cells improved the evoked auditory responses of deafened animals. However, the mechanism (protein-receptor interaction) whereby synapse formation occurs between implanted cells and host CN neurons remains unknown. We have identified neural SCs from mouse cochlear-vestibular ganglia and induced these SCs to differentiate into glutamatergic neurons (ScNs). We observed that neurotrophins stimulated neurite extensions from ScNs. However, neurotrophin supplementation did not significantly promote synaptogenesis between ScNs and CN neurons. Therefore, identification of mechanisms that stimulate auditory synapse regeneration is a major challenge to the restoration of auditory function. Recently, we developed a co-culture model using ScNs and mouse CN neurons to address this issue. We hypothesize that astrocyte-released thrombospondin-1 (TSP1) and the alpha2delta-1 (�2�-1) receptor are critical for SC-based synaptogenesis. To test this hypothesis, we propose the following specific aims: Aim 1: Determine whether TSP1 is a critical stimulator of ACM-induced synaptogenesis in vitro; Aim 2: Investigate the role of �2�1 in ACM-induced synaptogenesis in co-cultures; Aim 3: Examine the roles of TSP1 and �2�1 in CN synapse regeneration in vivo. This proposal studies a protein and a receptor that appear to be critical for the induction of synaptogenesis between SC-derived cells and CN neurons. When our in vitro and in vivo models are optimized in this proposal, we will study the strategies to develop and refine synaptic connections to ensure that the circuit is properly wired in a tonotopic organization in our future research. Identification of proteins and receptors that are important fo CN synapse formation not only will be fundamental to auditory pathway regeneration, but also will provide cues for synapse regeneration in other sensory systems.

描述（由申请人提供）：螺旋神经节神经元（SGN）及其与耳蜗核（CN）的突触是听觉系统的重要组成部分，在各种听觉障碍中受损。目前尚无生物方法可以再生 损坏的 SGN。我们这项提案的长期目标是使用干细胞 (SC) 衍生的神经元来替代受损的 SGN，并再生连接耳蜗和脑干的传入 CN 突触。在本提案中，我们将使用体外和体内模型重点研究 SC 衍生的谷氨酸能神经元和 CN 神经元之间的传入突触生成。毛细胞和 SC 衍生神经元之间的连接再生将在一个单独的项目中进行研究。最近的一项研究表明，植入的 SC 衍生细胞改善了耳聋动物的诱发听觉反应。然而，植入细胞和宿主 CN 神经元之间发生突触形成的机制（蛋白质-受体相互作用）仍然未知。我们从小鼠耳蜗前庭神经节中鉴定出神经 SC，并诱导这些 SC 分化为谷氨酸能神经元 (ScN)。我们观察到神经营养素刺激 ScN 的神经突延伸。然而，神经营养蛋白的补充并没有显着促进 ScN 和 CN 神经元之间的突触发生。因此，识别刺激听觉突触再生的机制是听觉功能恢复的主要挑战。最近，我们开发了一种使用 ScN 和小鼠 CN 神经元的共培养模型来解决这个问题。我们假设星形胶质细胞释放的血小板反应蛋白-1 (TSP1) 和 alpha2delta-1 (�2�-1) 受体对于基于 SC 的突触发生至关重要。为了检验这一假设，我们提出以下具体目标： 目标 1：确定 TSP1 是否是体外 ACM 诱导的突触发生的关键刺激因子；目标 2：研究 �2�1 在共培养中 ACM 诱导的突触发生中的作用；目标 3：检查 TSP1 和 �2�1 在体内 CN 突触再生中的作用。该提案研究了一种蛋白质和一种受体，它们似乎对于诱导 SC 衍生细胞和 CN 神经元之间的突触发生至关重要。当我们的体外和体内模型在本提案中得到优化时，我们将研究开发和完善突触连接的策略，以确保电路在音调中正确连接 组织我们未来的研究。对 CN 突触形成重要的蛋白质和受体的鉴定不仅对于听觉通路再生至关重要，而且还将为其他感觉系统中的突触再生提供线索。