Terreros Gonzalo, Munoz Felipe, Magdalena Matías, Soto-Donoso Manuel, Torres Nairo, D'Espessailles Amanda
Laboratorio de Neurociencia Sensorial, Perceptual y Cognitiva, Instituto de Ciencias de la Salud, Universidad de O'Higgins, Rancagua 2820000, Chile.
Escuela de Salud, Universidad de O'Higgins, Rancagua 2820000, Chile.
Nutrients. 2025 May 24;17(11):1786. doi: 10.3390/nu17111786.
: Obesity is a risk factor for several diseases; however, less has been researched about how diet-induced obesity may affect the auditory system. In this sense, the purpose of this study was to evaluate the effect of diet-induced obesity on the functionality and integrity of the outer hair cells, a key component of the organ of Corti, inside the cochlea. Furthermore, we hypothesized that adipose tissue (AT) status is associated with impaired outer hair cell auditory amplification in young C57BL/6 mice, contributing to increased vulnerability to hearing damage. : Weaning male C57BL/6J mice (7 weeks old) weighing 22-23 g were divided into two diet groups: (i) a control diet or (ii) a high-fat diet (HFD) for 12 or 16 weeks. Metabolic parameters (body and AT weight, glucose tolerance test), AT dysfunction markers (AT remodeling, adipocyte size, crown-like structures), and outer hair cell function (distortion products otoacoustic emissions (DPOAEs) threshold and amplitudes) and integrity (hair cells cell count) were evaluated. : We observed that mice fed an HFD for 16 weeks showed a higher DPOAE threshold against stimuli at 16 KHz and a lower count of outer hair cells in the medial section of the cochlea. These results demonstrate a correlation between body and AT weight specifically at 16 weeks of treatment, the time point at which we observed a marked AT dysfunction. : Taken together, our results suggest that obese mice with AT dysfunction have an altered auditory efferent system, characterized by a higher DPOAE threshold and a lower outer hair cell count in the medial section, which may impact signal transduction.
肥胖是多种疾病的风险因素;然而,关于饮食诱导的肥胖如何影响听觉系统的研究较少。从这个意义上说,本研究的目的是评估饮食诱导的肥胖对耳蜗内柯蒂氏器的关键组成部分——外毛细胞的功能和完整性的影响。此外,我们假设脂肪组织(AT)状态与年轻C57BL/6小鼠外毛细胞听觉放大功能受损有关,这会增加听力损伤的易感性。
将体重22 - 23克的断奶雄性C57BL/6J小鼠(7周龄)分为两个饮食组:(i)对照饮食组或(ii)高脂饮食(HFD)组,持续12周或16周。评估代谢参数(体重和AT重量、葡萄糖耐量试验)、AT功能障碍标志物(AT重塑、脂肪细胞大小、冠状结构)以及外毛细胞功能(畸变产物耳声发射(DPOAE)阈值和幅度)和完整性(毛细胞计数)。
我们观察到,喂食16周HFD的小鼠在16kHz刺激下的DPOAE阈值较高,且耳蜗内侧部分的外毛细胞计数较低。这些结果表明,在治疗16周时,即我们观察到明显的AT功能障碍的时间点,体重与AT重量之间存在相关性。
综上所述,我们的结果表明,患有AT功能障碍的肥胖小鼠的听觉传出系统发生了改变,其特征是DPOAE阈值较高,耳蜗内侧部分的外毛细胞计数较低,这可能会影响信号转导。