Interactions of hearing loss and diabetes mellitus in the middle age CBA/CaJ mouse model of presbycusis

• Published in: Hearing research Vol. 249; no. 1; pp. 44 - 53
• Main Authors: Vasilyeva, Olga N., Frisina, Susan T., Zhu, Xiaoxia, Walton, Joseph P., Frisina, Robert D.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.03.2009; Elsevier
• Subjects: Aging - physiology; Animals; Auditory brainstem response; Auditory midbrain; Auditory Threshold; Biological and medical sciences; Blood Glucose - metabolism; CBA/CaJ mice; Diabetes; Diabetes Mellitus, Experimental - complications; Diabetes Mellitus, Experimental - physiopathology; Diabetes Mellitus, Type 2 - complications; Disease Models, Animal; Distortion product otoacoustic emissions; Ear and associated structures. Auditory pathways and centers. Hearing. Vocal organ. Phonation. Sound production. Echolocation; Ear, auditive nerve, cochleovestibular tract, facial nerve: diseases, semeiology; Evoked Potentials, Auditory; Evoked Potentials, Auditory, Brain Stem; Fundamental and applied biological sciences. Psychology; Hearing loss; Humans; Inferior Colliculi - physiopathology; Inferior colliculus; Male; Medical sciences; Mice; Mice, Inbred CBA; Non tumoral diseases; Otoacoustic Emissions, Spontaneous; Otorhinolaryngology. Stomatology; Presbycusis - complications; Presbycusis - physiopathology; Vertebrates: nervous system and sense organs; T1DM; T2DM; OAEs; IHC; Inferior colliculus; SPF; DM; OHC; SPL; ABR; Auditory brainstem response; Auditory midbrain; ANOVA; BW; STZ; IC; Distortion product otoacoustic emissions; NFAEP; EEG; GM; HINT; IP; IAC; CBA/CaJ mice; Hearing loss; DPOAEs; RMS; RM; Diabetes; Endocrinopathy; Type 2 diabetes; Animal model; Noise; Central nervous system; Electrophysiology; Auditory disorder; Autoimmune disease; Glucose; Blood; Encephalon; Distorsion product otoacoustic emission; ENT disease; Age; Human; Immunopathology; Rodentia; Metabolic diseases; Feeding; Vertebrata; Hearing; Mammalia; Colliculus inferior; Diet; Mouse; Type 1 diabetes; Auditory evoked potential; Presbyacusia; Auditory pathway
• ISSN: 0378-5955; 1878-5891; 1878-5891
• DOI: 10.1016/j.heares.2009.01.007

Recently, we characterized the more severe nature of hearing loss in aged Type 2 diabetic human subjects [Frisina, S.T., Mapes, F., Kim, S., Frisina, D.R., Frisina, R.D., 2006. Characterization of hearing loss in aged type II diabetics. Hear. Res. 211, 103–113]. The current study prospectively assessed hearing abilities in middle age CBA/CaJ mice with Type 1 diabetes mellitus (T1DM) (STZ injection) or Type 2 diabetes mellitus (T2DM) (high fat diet), for a period of 6 months. Blood glucose, body weight and auditory tests (Auditory Brainstem Response-ABR, Distortion Product Otoacoustic Emissions-DPOAE) were evaluated at baseline and every 2 months. Tone and broad-band noise-burst responses in the inferior colliculus were obtained at 6 months. Body weights of controls did not change over 6 months (∼32 g), but there was a significant (∼5 g) decline in the T1DM, while T2DM exhibited ∼10 g weight gain. Blood glucose levels significantly increased: 3-fold for T1DM, 1.3-fold for T2DM; with no significant changes in controls. ABR threshold elevations were found for both types of diabetes, but were most pronounced in the T2DM, starting as early as 2 months after induction of diabetes. A decline of mean DPOAE amplitudes was observed in both diabetic groups at high frequencies, and for the T2DM at low frequencies. In contrast to ABR thresholds, tone and noise thresholds in the inferior colliculus were lower for both diabetic groups. Induction of diabetes in middle-aged CBA/CaJ mice promotes amplification of age-related peripheral hearing loss which makes it a suitable model for studying the interaction of age-related hearing loss and diabetes. On the other hand, initial results of effects from very high blood glucose level (T1DM) on the auditory midbrain showed disruption of central inhibition, increased response synchrony or enhanced excitation in the inferior colliculus.