Cochlear neuropathy in human presbycusis: Confocal analysis of hidden hearing loss in post-mortem tissue.
Cochlear neuropathy in human presbycusis: Confocal analysis of hidden hearing loss in post-mortem tissue.
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DOI：
10.1016/j.heares.2015.04.014
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发表时间：
2015-09
期刊：
影响因子：
2.8
通讯作者：
Liberman MC
中科院分区：
文献类型：
--
作者：
Viana LM;O'Malley JT;Burgess BJ;Jones DD;Oliveira CA;Santos F;Merchant SN;Liberman LD;Liberman MC
最近的动物研究表明，在噪音引起的听力损失和与年龄相关的听力损失中，耳蜗突触比毛细胞更脆弱。这种突触病变在传统的组织病理学分析中是看不见的，因为螺旋神经节中的耳蜗神经细胞体可以存活多年，而突触分析需要特殊的免疫染色或连续切片电子显微镜。在这里，我们表明，在小鼠中进行突触计数、毛细胞计数、神经元计数以及传入和传出纤维分化的相同四重免疫染色方案可以应用于人类颞骨，当在死后 9 小时内收获并制备成解剖的整个感觉上皮和骨螺旋层时。对五只年龄在 54 至 89 岁、没有任何耳科疾病史的“正常”耳朵进行的定量分析表明，尽管毛细胞群接近正常，但耳蜗突触病变和耳蜗神经周围轴突的退化可能是人类老年性耳聋的重要组成部分。尽管原发性耳蜗神经变性预计不会影响听力阈值，但它可能是噪声中听力问题的关键，而噪声是老化耳朵听力能力下降的特征。
Recent animal work has suggested that cochlear synapses are more vulnerable than hair cells in both noise-induced and age-related hearing loss. This synaptopathy is invisible in conventional histopathological analysis, because cochlear nerve cell bodies in the spiral ganglion survive for years, and synaptic analysis requires special immunostaining or serial-section electron microscopy. Here, we show that the same quadruple-immunostaining protocols that allow synaptic counts, hair cell counts, neuronal counts and differentiation of afferent and efferent fibers in mouse can be applied to human temporal bones, when harvested within 9 hrs post-mortem and prepared as dissected whole mounts of the sensory epithelium and osseous spiral lamina. Quantitative analysis of five “normal” ears, aged 54 to 89 yrs, without any history of otologic disease, suggests that cochlear synaptopathy and the degeneration of cochlear nerve peripheral axons, despite a near-normal hair cell population, may be an important component of human presbycusis. Although primary cochlear nerve degeneration is not expected to affect audiometric thresholds, it may be key to problems with hearing in noise that are characteristic of declining hearing abilities in the aging ear.