Blebbistatin Inhibits Neomycin-Induced Apoptosis in Hair Cell-Like HEI-OC-1 Cells and in Cochlear Hair Cells

Song Gao; Cheng Cheng; Maohua Wang; Pei Jiang; Liyan Zhang; Ya Wang; Huihui Wu; Xuanfu Zeng; Hui Wang; Xia Gao; Yongming Ma; Renjie Chai

doi:10.3389/fncel.2019.00590

Blebbistatin Inhibits Neomycin-Induced Apoptosis in Hair Cell-Like HEI-OC-1 Cells and in Cochlear Hair Cells

Front Cell Neurosci. 2020 Feb 5:13:590. doi: 10.3389/fncel.2019.00590. eCollection 2019.

Authors

Song Gao¹, Cheng Cheng^{2

3}, Maohua Wang⁴, Pei Jiang⁵, Liyan Zhang⁵, Ya Wang¹, Huihui Wu¹, Xuanfu Zeng¹, Hui Wang⁶, Xia Gao^{2

3}, Yongming Ma¹, Renjie Chai^{5

7

8

9

10}

Affiliations

¹ Department of Otolaryngology, Affiliated People's Hospital of Jiangsu University, Zhenjiang, China.
² Department of Otolaryngology Head and Neck Surgery, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Jiangsu Provincial Key Medical Discipline (Laboratory), Nanjing, China.
³ Research Institute of Otolaryngology, Nanjing, China.
⁴ Department of Otolaryngology, Head and Neck Surgery, XiangYa School of Medicine, Central South University, Changsha, China.
⁵ MOE Key Laboratory for Developmental Genes and Human Disease, Institute of Life Sciences, Southeast University, Nanjing, China.
⁶ Department of Otolaryngology Head and Neck Surgery, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
⁷ Co-Innovation Center of Neuroregeneration, Nantong University, Nantong, China.
⁸ Institute for Stem Cell and Regeneration, Chinese Academy of Science, Beijing, China.
⁹ Beijing Key Laboratory of Neural Regeneration and Repair, Capital Medical University, Beijing, China.
¹⁰ Jiangsu Province High-Tech Key Laboratory for Bio-Medical Research, Southeast University, Nanjing, China.

Abstract

Aging, noise, and ototoxic drug-induced hair cell (HC) loss are the major causes of sensorineural hearing loss. Aminoglycoside antibiotics are commonly used in the clinic, but these often have ototoxic side effects due to the accumulation of oxygen-free radicals and the subsequent induction of HC apoptosis. Blebbistatin is a myosin II inhibitor that regulates microtubule assembly and myosin-actin interactions, and most research has focused on its ability to modulate cardiac or urinary bladder contractility. By regulating the cytoskeletal structure and reducing the accumulation of reactive oxygen species (ROS), blebbistatin can prevent apoptosis in many different types of cells. However, there are no reports on the effect of blebbistatin in HC apoptosis. In this study, we found that the presence of blebbistatin significantly inhibited neomycin-induced apoptosis in HC-like HEI-OC-1 cells. We also found that blebbistatin treatment significantly increased the mitochondrial membrane potential (MMP), decreased ROS accumulation, and inhibited pro-apoptotic gene expression in both HC-like HEI-OC-1 cells and explant-cultured cochlear HCs after neomycin exposure. Meanwhile, blebbistatin can protect the synaptic connections between HCs and cochlear spiral ganglion neurons. This study showed that blebbistatin could maintain mitochondrial function and reduce the ROS level and thus could maintain the viability of HCs after neomycin exposure and the neural function in the inner ear, suggesting that blebbistatin has potential clinic application in protecting against ototoxic drug-induced HC loss.

Keywords: ROS; aminoglycoside; apoptosis; blebbistatin; hair cell; hearing; synaptic plasticity.