超越兴奋毒性：谷氨酸非依赖性机制介导噪声诱导的突触病并损害遗传性耳聋的基因治疗
Beyond Excitotoxicity: Glutamate-Independent Mechanisms Underlie Noise-Induced Synaptopathy and Compromise Gene Therapy for Hereditary Deafness.
文献信息
| PMID | 42888847 |
|---|---|
| 原文 | 在 PubMed 查看原文 ↗ |
| 发表日期 | 2026 |
| 作者 | Changyun Yu |
| 作者单位 | Department of Otolaryngology Head and Neck Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450000, China. |
| 期刊 | Molecular therapy : the journal of the American Society of Gene Therapy |
| SCI 分区 | Q1 |
| IF | 12.7 |
| 研究类型 | 基础研究 · 基础／转化 |
| 所属专科 | 耳科 |
中文摘要
背景： 噪声诱导的听力损失（NIHL）经典上被归因于谷氨酸兴奋毒性，但突触谷氨酸释放的确切必要性尚未通过遗传学方法进行检验。方法：在此，我们使用Vglut3敲除（Vglut3-KO）小鼠研究噪声诱导的耳蜗损伤，该小鼠缺乏来自内毛细胞的谷氨酸能传递。结果：在116 dB SPL噪声暴露后，野生型（WT）小鼠表现出永久性阈值偏移、持续的ABR波I振幅降低，以及基底转中带突触和外毛细胞（OHC）的显著丢失。出乎意料的是，Vglut3-KO小鼠尽管无法释放谷氨酸，也表现出显著的突触丢失，揭示了突触病的谷氨酸非依赖性机制。对噪声暴露耳蜗的蛋白质组学分析鉴定出62个差异表达蛋白，富集于突触和细胞外基质通路，包括Rps6ka1、Cplx2和Cdk5的上调以及Ppa2的下调。对Vglut3-KO小鼠的比较分析进一步揭示了233个差异表达蛋白，其中突触、线粒体和ECM通路广泛下调。重要的是，噪声暴露严重损害了Vglut3-KO小鼠中AAV8-Vglut3基因治疗的疗效：未暴露的突变体实现了完全功能恢复，而噪声暴露的动物未能达到正常听力阈值，尽管免疫荧光证实所有耳蜗转中VGLUT3表达均得到恢复。结论：这些发现表明，高强度噪声通过涉及突触和ECM破坏的兴奋毒性和非兴奋毒性机制诱导突触病，并且声创伤造成持续的OHC丢失，限制了基因治疗的结果，强调了在等待治疗的遗传性耳聋患者中需要全面的耳保护策略。
英文摘要
Noise-induced hearing loss (NIHL) is classically attributed to glutamate excitotoxicity, yet the precise requirement for synaptic glutamate release remains untested using genetic approaches. Here, we investigated noise-induced cochlear damage using Vglut3 knockout (Vglut3-KO) mice, which lack glutamatergic transmission from inner hair cells. Following 116 dB SPL noise exposure, wild-type (WT) mice exhibited permanent threshold shifts, persistent ABR wave I amplitude reduction, and significant loss of both ribbon synapses and outer hair cells (OHC) in the basal turn. Unexpectedly, Vglut3-KO mice also exhibited significant synapse loss despite their inability to release glutamate, revealing glutamate-independent mechanisms of synaptopathy. Proteomic analysis of noise-exposed cochleae identified 62 differentially expressed proteins enriched in synaptic and extracellular matrix pathways, including upregulation of Rps6ka1, Cplx2, and Cdk5, and downregulation of Ppa2. Comparative profiling of Vglut3-KO mice further revealed 233 differentially expressed proteins, with widespread downregulation of synaptic, mitochondrial, and ECM pathways. Importantly, noise exposure severely compromised AAV8-Vglut3 gene therapy efficacy in Vglut3-KO mice: while unexposed mutants achieved complete functional recovery, noise-exposed animals failed to attain normal hearing thresholds, with VGLUT3 expression restored across all cochlear turns as confirmed by immunofluorescence. These findings demonstrate that high-intensity noise induces synaptopathy through both excitotoxic and non-excitotoxic mechanisms involving synaptic and ECM disruption, and that acoustic trauma creates persistent OHC loss limiting gene therapy outcomes, underscoring the need for comprehensive otoprotective strategies in hereditary deafness patients awaiting treatment.