Analysis of the modulating effect of pegylated IGF1 (pegIGF1) on the hearing function of a mouse model for auditory neuropathy

The progressive motoneuronopathy (pmn) mouse is a model for a recessively hereditary motoneuron disease caused by a mutation in the tubulin-specific chaperone E gene. The loss of motoneuron cell bodies appears as a consequence of axonal degeneration. The animals also develop a progressive hearing loss after normal hearing initiation, which is characterized by a pathology of the auditory nerve. Previous studies, treatment with pegIGF1 in the mouse model has been shown to benefit lifespan, weight, muscle strength and motor coordination. This indicates a possible preservation of neurons.

The aim of this study was to evaluate the effect of pegIGF1 on the pathology of the hearing system. Therefore, animals were treated with pegIGF1 from day 14 postnatal and electrophysiological examinations were performed on postnatal day 21 and 28. The cochleae were processed immunohistologically. The number and morphology of hair cells and neurons were analyzed.

In the electrophysiologiy an auditory neuropathy with elevated ABR thresholds but normal OAE thresholds compared to control animals could be measured. Treatment with pegIGF1 did not result in an improvement in hearing function. Histologically, all animals showed tubular axonal damage, with conspicuous number and morphology of hair cells. However, an increased survival of efferent neurons in the cochlea of treated pmn mice was observed. In summary, the pmn mouse is a suitable model of auditory neuropathy and offers the opportunity to gain more insights into this disease pattern and to evaluate new treatment approaches.

Poster-PDF A-1314.pdf

Conflict of interest

Der Erstautor gibt keinen Interessenskonflikt an.

Publication History

Article published online:
13 May 2021