Development of a new treatment strategy for deafness associated with mitochondrial impairent

2015 Fiscal Year Final Research Report

• Project/Area Number: 26670737
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Otorhinolaryngology
• Research Institution: The University of Tokyo
• Principal Investigator: yamasoba tatsuya 東京大学, 医学部附属病院, 教授 (60251302)
• Co-Investigator(Kenkyū-buntansha): NAKAJIMA Toshiaki 東京大学, 医学部附属病院, 臨床登録員 (50227790)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 難聴 / ミトコンドリア / 水素 / タウリン / コエンザイムQ10 / ゲルマニウム

Outline of Final Research Achievements

CBA mice that were given germanium dioxide (GeO2) orally developed progressive hearing loss and became deaf by 5 months. DNA microarray analysis demonstrated upregulation of genes associated with apotosis, etc and downregulation of genes associated with energy metabolism, hearing, etc. QRT-PCR also confirmed downregulation of genes related to mitochondrial respiratory chain enzymes. Histopathologically, degeneration of the cochlear tissues, especially the stria vascularis and spiral ganglion, was observed in animals given GeO2. When given also taurine, hydrogen-rich water, or CoQ10, the animals showed less hearing loss and cochlear degeneration, with taurine showing the strongest effect. When a combination of taurine, CoQ10, and hydrogen-rich water was given to patients with mitochondrial DNA 3243 point mutation, a majority of them showed little progression of hearing loss during follow-up period, and only one developed acute exacerbation.

Free Research Field

耳鼻咽喉科学