It is known that hyperlipidemia is a risk factor for sensorineural hearing loss. However, the biological mechanisms underlying hyperlipidemia and hearing impairment have not been completely elucidated in the cochlea. Based on our previous study of human subjects, elderly people taking drugs for hyperlipidemia showed better hearing than those not taking any medications. We hypothesized that drugs for hyperlipidemia, such as statins, may have the potential to prevent hearing impairment. The aim of this study was to investigate the correlation between hyperlipidemia and hearing impairment and the hearing preservation effect of atorvastatin using a hyperlipidemic mouse model with diet-induced obesity (DIO). Here, we demonstrate that DIO mice had a significant hearing impairment as well as increased levels of reactive oxygen species (ROS) and hair cell death due to reduced levels of pAKT and superoxide dismutase 2 (SOD2). However, these changes were significantly prevented by atorvastatin. Oxidative stress-induced intrinsic apoptosis was decreased by the high expression of Nrf2 and antioxidant genes, which improved mitochondrial function and ROS via activation of the PI3K-pAKT pathway by atorvastatin. Therefore, atorvastatin has the potential to prevent hearing impairment via redox balance in the presence of hyperlipidemia.

众所周知，高脂血症是感觉神经性听力损失的危险因素。但是，耳蜗中尚未完全阐明高脂血症和听力障碍的生物学机制。根据我们之前对人类受试者的研究，与未服用任何药物的老年人相比，服用高脂血症的老年人的听力更好。我们假设高脂血症药物（如他汀类药物）可能具有预防听力障碍的潜力。这项研究的目的是使用饮食诱发性肥胖症（DIO）的高脂血症小鼠模型研究高脂血症和听力障碍与阿托伐他汀的听力保存效果之间的相关性。这里，我们证明DIO小鼠由于pAKT和超氧化物歧化酶2（SOD2）的水平降低而具有明显的听力障碍，以及活性氧（ROS）和毛细胞死亡的水平增加。但是，阿托伐他汀可有效阻止这些变化。Nrf2和抗氧化剂基因的高表达减少了氧化应激诱导的内在凋亡，从而改善了线粒体功能和ROS通过阿托伐他汀激活PI3K-pAKT途径。因此，阿托伐他汀有可能在高血脂的情况下通过氧化还原平衡防止听力受损。