Histopathological Change of Age-Related Hearing Loss in Female Advanced-Aged CBA/CaJ Mice

This study on age-related hearing loss in advanced-age CBA/CaJ mice reveals that hearing loss involves a combination of acoustic cochlear damage and metabolic changes due to mitochondrial dysfunction and oxidative stress. The research involved 11 aged mice and 12 young mice for comparison. Key findings include a peak loss of outer hair cells at 11.3 kHz, significant synapse loss at 5.6 kHz, atrophy and microthrombus formation in the stria vascularis, and endolymphatic hydrops in the cochlear apical turn. Additionally, there was a reduction in cell numbers in the spiral ganglion and cochlear nerve, along with increased oxidative stress markers. These findings suggest that addressing both chronic sound exposure and metabolic changes is crucial for preventing and treating age-related hearing loss.