Korean J Otorhinolaryngol-Head Neck Surg.  2008 Dec;51(12):1093-1098.

Effect of Growth Factors on Hearing Restoration in Deafened Animal Model

• Kim JH
• Park SN
• Yeo SW
• Kim YH
• Jin SY
• Kim JH
• Cho SJ
• Kim JH
• Choi MY
• Park KH

Abstract

BACKGROUND AND OBJECTIVES: Sensorineural hearing loss is caused by ototoxic drugs, radiation therapy, noise exposure and trauma, etc. They make irreversible changes in cochlear hair cells and degeneration of spiral ganglion neurons. It is known that neurotrophins and other growth factors have an important role in protectingcochlear hair cells and spiral ganglion neurons. We designed this study to analyze the effect of neurotrophins and growth factors delivered to the inner ear of deafened guinea pig. MATERIALS AND METHOD: Healthy 15 guinea pigs with normal Preyer's reflex were chosen, and were made deaf by infusion of kanamycin and ethacrynic acid. Myringotomy was done to both ears, normal saline injected into the left ear, and BDNF (brainderived neurotrophic factor), GDNF (glial cell derived neurotrophic factor), NT-3 (neurotrophin-3), IGF (insulin-like growth factor), EGF (epidermal growth factor), FGF (fibroblast growth factor) were injected in the right ear.
RESULTS
Statistically significant hearing gain was obtained up to 35.00+/-13.78 dB in the group 1 (BDNF, GDNF, NT-3 treated group), and up to 34.0+/-5.47 dB in the group 2 (IGF treated group). However, no statistically significant hearing gain was observed in the group 3 (EGF, FGF treated group).
CONCLUSION
We observed statistically important improvement of hearing threshold in the BDNF, GDNF, NT-3 treated group and IGF treated group.

Keyword

Growth factors; Guinea pig; Hearing gain

MeSH Terms

Animals
Brain-Derived Neurotrophic Factor
Ear
Ear, Inner
Epidermal Growth Factor
Ethacrynic Acid
Glial Cell Line-Derived Neurotrophic Factor
Guinea
Guinea Pigs
Hair
Hearing
Hearing Loss, Sensorineural
Intercellular Signaling Peptides and Proteins
Kanamycin
Models, Animal
Nerve Growth Factors
Neurons
Noise
Reflex
Spiral Ganglion
Brain-Derived Neurotrophic Factor
Epidermal Growth Factor
Ethacrynic Acid
Glial Cell Line-Derived Neurotrophic Factor
Intercellular Signaling Peptides and Proteins
Kanamycin
Nerve Growth Factors