Mixed conductive and sensorineural hearing loss in LP/J mice

Area of Science:

• Otolaryngology
• Auditory Neuroscience
• Genetics

Background:

• Otosclerosis is a human hearing disorder characterized by abnormal bone growth in the middle ear.
• The LP/J inbred mouse strain has been proposed as a potential animal model for studying otosclerosis.
• Understanding the progression of hearing loss in this model is crucial for developing therapeutic strategies.

Purpose of the Study:

• To investigate the auditory function and pathological changes in LP/J mice.
• To compare hearing thresholds in LP/J mice with control CBA/Ca mice.
• To evaluate the suitability of LP/J mice as a model for human otosclerosis.

Main Methods:

• Auditory brainstem response testing using air and bone conduction thresholds.
• Histopathological examination of middle ear and cochlear structures.
• Microbiological analysis of middle ear specimens.

Main Results:

• LP/J mice demonstrated elevated air and bone conduction thresholds, indicating a mixed hearing loss.
• Early-stage LP/J mice (20 days) showed raised thresholds without significant hair cell loss or bony lesions.
• Later-stage LP/J mice (225 days) exhibited extensive hair cell degeneration and significant middle ear bone overgrowth.

Conclusions:

• The LP/J mouse strain develops a progressive hearing loss consistent with otosclerosis.
• Pathological changes, including sensorineural and conductive components, worsen with age in this model.
• LP/J mice represent a valuable model for investigating the mechanisms and potential treatments for otosclerosis.