Senolytic treatment alleviates cochlear senescence and delays age-related hearing loss in C57BL/6J mice

BACKGROUND: Age-related hearing loss (ARHL) is a prevalent sensory deficit that significantly affects quality of life in older individuals. Cellular senescence contributes to various age-related degenerative disorders. However, its effect on ARHL remains unclear. PURPOSE: The aim of this study was to explore the therapeutic potential of senolytics in attenuating cochlear senescence and delaying the progression of ARHL. METHODS: The senolytic drugs dasatinib and quercetin (D + Q) were used to target senescent cells at different stages of ARHL in C57BL/6J mice. The impact of D + Q treatment on ARHL progression and cochlear degeneration was also assessed. Additionally, the protective effects of D + Q treatment were evaluated in HEI-OC1 auditory cells and cochlear explants. Transcriptomic analysis was conducted on cochlear explants subjected to different treatments. RESULTS: D + Q treatment at an early stage of ARHL significantly delayed ARHL progression and alleviated cochlear degeneration in male and female C57BL/6J mice. Treatment of mice with normal hearing also mitigated age-related hair cell loss. In HEI-OC1 auditory cells, D + Q treatment exerted protective effects by alleviating the senescence-associated secretory phenotype (SASP). Transcriptomic analysis of cochlear explants revealed that downregulation of inflammatory cytokines and chemokines was involved in the beneficial effects of D + Q treatment against cellular senescence. Mechanistically, D + Q treatment alleviated hair cell senescence via binding to NF-κB and inhibiting its activity. CONCLUSION: Senolytics may offer a novel therapeutic strategy for attenuating cochlear senescence and slowing the progression of ARHL.