New strategies for cochlear afferent dendrite and synaptic regeneration.

2014 Fiscal Year Final Research Report

• Project/Area Number: 25861551
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Otorhinolaryngology
• Research Institution: Akita University (2014); Kyoto University (2013)
• Principal Investigator: ASAKA Nakarin 秋田大学, 医学(系)研究科(研究院), 助教 (40637625)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: らせん神経 / IGF-1

Outline of Final Research Achievements

Previous studies in animals and humans have demonstrated the efficacy of insulin-like growth factor-1 (IGF-1) for hearing recovery in acute hearing loss. In the present study, we focus on regeneration of the synapse between inner hair cells (IHCs) and spiral ganglion neurons (SGNs) as a mechanism of hearing recovery following IGF-1 application. To test the capability of IGF-1 for promoting regeneration of IHC-SGN synapses, an ex vivo model of excitotoxicity was employed. In cochlear explants, IGF-1 promoted IHC-SGN regeneration after excitotoxic insult via the phosphoinositide 3-kinase-Akt signaling pathway. These results demonstrated that IGF-1 promoted regeneration of IHC-SGN synapses, which may be involved in mechanisms of hearing recovery following IGF-1 treatment.

Free Research Field

耳科学