Qingping Ma1,2,3 · Qixuan Wang4  · Zixuan Zhu5  · Qian Zhou1,2,3 · Zhongying Wang1,2,3 · Minfei Qian6  · Teng Li5  · Xixi Gu5  · Zechuan Chen5  · Xueling Wang1,3,7 · Xiaoming Zhang5  · Zhiwu Huang1,2,3,8

1 Department of Otolaryngology-Head and Neck Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China 

2 Ear Institute, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China 

3 Shanghai Key Laboratory of Translational Medicine on Ear and Nose Diseases, Shanghai 200125, China 

4 Department of Facial Plastic and Reconstructive Surgery, Eye & ENT Hospital of Fudan University, ENT Institute, Eye & ENT Hospital of Fudan University, NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China 

5 National Key Laboratory of Immune Response and Immunotherapy, Shanghai Institute of Immunity and Infection, Chinese Academy of Sciences, Shanghai 200031, China 

6 Department of Otolaryngology-Head and Neck Surgery, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200127, China 

7 Biobank, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200125, China 

8 College of Health Science and Technology, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China

Abstract

Circadian sensitivity significantly influences the severity of noise-induced hearing loss (NIHL), but the underlying mechanisms remain unclear. Here, we applied single-cell RNA sequencing to 97,043 cochlear cells, identifying macrophages as the primary immune responders to acoustic trauma, with a notable increase in their proportion in the cochlea. Immunofluorescence confirmed significant recruitment and activation of cochlear macrophages following noise exposure, while in vivo macrophage depletion resulted in the recovery of hearing. Furthermore, analyses of differentially-expressed genes and pathways revealed pronounced activation of NLRP3 inflammasome signaling in macrophages during night-time noise exposure. Measurements of elevated IL-1β and IL-18 expression in cochlear macrophages by multiplex immunohistochemistry correlated with heightened inflammation in the night-time exposure group. These findings were further confirmed by the administration of the selective NLRP3 inhibitor CY-09, which mitigated inflammasome activation, preserved synaptic integrity, and protect against hearing loss. In conclusion, our findings underscore the role of macrophage-driven NLRP3 inflammasome activation in mediating circadian variations in cochlear damage, offering a potential therapeutic target for mitigating NIHL.

Keywords

Noise-induced hearing loss; Macrophage; NLRP3 infammasome; Circadian rhythm

[SpringerLink]