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: 8806554
• 负责人: Zhengqing Hu
• 金额: $ 31.98万
• 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/8806554
• 关键词: Address; Adult; Affinity; Animals; Astrocytes; Auditory; Auditory Evoked Potentials; Auditory system; Binding; Biological; Brain Stem; Cells; Chemicals; Chronic; Cochlea; Cochlear nucleus; Coculture Techniques; Conditioned Culture Media; Cues; Data; Disease; Dose; Ensure; Future; Gene Expression; Generations; Glutamates; Goals; Hair Cells; Health; Hearing; Human; 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; neurotrophic factor; overexpression; postnatal; receptor; relating to nervous system; 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(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，在各种听力障碍中受到损害。目前，还不存在生物再生的方法。 已损坏的SGN。我们这项提议的长期目标是使用干细胞(SC)来源的神经元来取代受损的SGN，并再生连接耳蜗和脑干的传入CN突触。在这个方案中，我们将使用体外和体内模型，重点研究干细胞来源的谷氨酸能神经元和CN神经元之间的传入突触产生。再生毛细胞和干细胞来源的神经元之间的连接将在另一个项目中进行研究。最近的一项研究表明，移植的干细胞来源的细胞改善了聋人动物的诱发听觉反应。然而，移植细胞和宿主CN神经元之间形成突触的机制(蛋白质-受体相互作用)仍不清楚。我们从小鼠耳蜗节-前庭神经节中鉴定了神经干细胞，并将其诱导分化为谷氨酸能神经元。我们观察到神经营养因子刺激了来自SCN的轴突延伸。然而，补充神经营养素并不能显著促进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恢复听觉功能的主要挑战。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。我们推测星形胶质细胞释放的凝血酶敏感蛋白-1(TSP1)和α-β-1(α2-1)受体对基于SC的突触发生至关重要。为了验证这一假说，我们提出了以下具体目标：目的1：确定TSP1是否是ACM诱导的体外突触发生的关键刺激因子；目的2：研究TSP1在ACM诱导的共培养中的突触发生中的作用；目标3：研究TSP1和β2？1在体内CN突触再生中的作用。这项建议研究了一种蛋白质和一种受体，它们似乎对诱导干细胞来源的细胞和CN神经元之间的突触生成至关重要。当我们的体外和活体模型在这个方案中得到优化时，我们将研究开发和改进突触连接的策略，以确保电路正确地连接到强直性 组织在我们未来的研究中。识别对CN突触形成至关重要的蛋白质和受体不仅是听觉通路再生的基础，也将为其他感觉系统的突触再生提供线索。