Pleiotrophin modulates neurite outgrowth of spiral ganglion neurons in vitro

Introduction:

Cochlear implants (CIs) are the only available therapy for severe to profound sensorineural hearing loss when patients do not achieve satisfactory speech perception with hearing aids. Beside great success with CI-technology during recent decades, there are still patients with not satisfying results. One reason for that may be due to the bioelectrical interface, where the stimulation electrode gets in touch with neurons or their neurites. There are several neurotrophic factors for SGNs known which may improve the performance of CIs. Pleiotrophin is a well described neurotrophic factor for spinal motor neurons and is also expressed in the cochlea of postnatal mice.

Methods:

In the present study, we investigated the effect of Pleiotrophin on spiral ganglion neurons of postnatal mice. Neuron survival and neurite outgrowth of dissociated neurons and organotypic explant cultures was studied in detail.

Results & Conclusion:

Pleiotrophin enhanced neurite length of spiral ganglion neurons significantly in our experimental setup. Pleiotrophin conditions additionally treated with BDNF and NT-3 did not show increased number of neurons or neurites in an additive effect. Our results suggest that Pleiotrophin interacts with spiral ganglion neurons through the ανβ-3 integrin pathway. Overall, PTN seems to be a neurotrophic factor for SGNs and may lead to a better treatment of sensorineural hearing loss in the future.

Publication History

Publication Date:
18 April 2018 (online)