Transformative Otology and Neuroscience Center, Binzhou Medical University, 346 Guanhai Road, Yantai 264003, Shandong, PR China.
Neuroscience. 2013 May 1;237:1-6. doi: 10.1016/j.neuroscience.2013.01.052. Epub 2013 Feb 4.
The Cdh23(erl/erl) mice are a novel mouse model for DFNB12 and are characterized by progressive hearing loss. In this study, erythropoietin (EPO) was given to the Cdh23(erl/erl) mice by intraperitoneal injection every other day from P7 for 7 weeks. Phosphate-buffered saline-treated or untreated Cdh23(erl/erl) mice were used as controls. Auditory-evoked brainstem response (ABR) thresholds and distortion product oto-acoustic emission (DPOAE) were measured in the mouse groups at the age of 4, 6 and 8 weeks. The results show that EPO can significantly decrease the ABR thresholds in the Cdh23(erl/erl) mice as compared with those of the untreated mice at stimulus frequencies of click, 8-, 16- and 32-kHz at three time points. Meanwhile, DPOAE amplitudes in the EPO-treated Cdh23(erl/erl) mouse group were significantly higher than those of the untreated groups at f2 frequency of 15383 Hz at the three time points. Furthermore, the mean percentage of outer hair cell loss at middle through basal turns of cochleae was significantly lower in EPO-treated Cdh23(erl/erl) mice than in the untreated mice (P<0.05). This is the first report that EPO acts as an otoprotectant in a DFNB12 mouse model with progressive hearing loss.
Cdh23(erl/erl) 小鼠是一种新型的 DFNB12 小鼠模型，其特征是进行性听力损失。在这项研究中，从 P7 开始，每隔一天通过腹腔注射向 Cdh23(erl/erl) 小鼠给予促红细胞生成素 (EPO)，持续 7 周。用磷酸盐缓冲盐水处理或未处理的 Cdh23(erl/erl) 小鼠作为对照。在 4、6 和 8 周龄时，在各组小鼠中测量听觉诱发的脑干反应 (ABR) 阈值和畸变产物耳声发射 (DPOAE)。结果表明，与未处理组相比，EPO 可显著降低 Cdh23(erl/erl) 小鼠在三个时间点的刺激频率为 click、8、16 和 32-kHz 时的 ABR 阈值。同时，在三个时间点，EPO 处理的 Cdh23(erl/erl) 小鼠组的 DPOAE 幅度在 f2 频率为 15383 Hz 时明显高于未处理组。此外，EPO 处理的 Cdh23(erl/erl) 小鼠耳蜗中间和基底转外毛细胞的平均缺失率明显低于未处理组 (P<0.05)。这是首次报道 EPO 作为一种进行性听力损失的 DFNB12 小鼠模型中的耳保护剂。
