Prevention of progressive hearing loss in a mouse model of diabetes by oral intake of eicosapentaenoic acid ethyl ester.

ABSTRACT

BACKGROUND: The prevalence of hearing impairment in patients with diabetes was significantly higher, and the development of preventive methods is desirable. AIMS/OBJECTIVES: This study examined the effects of eicosapentaenoic acid (EPA) administration on the prevention of early hearing loss in diabetic mice. MATERIALS AND METHODS: Tsumura, Suzuki, Obese Diabetes (TSOD) mice were used as a model of diabetes and Tsumura, Suzuki, Non Obesity (TSNO) mice were used as controls. The animals were divided into three groups the TSNO group and the TSOD (EPA-) group (provided sunflower oil), and the TSOD (EPA+) group (provided EPA). Auditory brainstem responses (ABRs) were measured and the cochlea was evaluated histologically. RESULTS: The TSOD (EPA+) group showed a lower tendency to increase thresholds than the TSOD (EPA-) group. The TSOD (EPA+) group had a significantly lower ABR threshold than the TSOD (EPA-) group from 11 to 14 months of age at 4 kHz. Narrowing of the capillary lumens in the stria vascularis and thickening of the vessel wall in the modiolus were observed in the TSOD (EPA-) group. CONCLUSIONS AND SIGNIFICANCE: It was suggested that the suppression of cochlear vascular atherosclerosis by EPA administration in TSOD mice suppressed early age-related hearing loss.