TY - JOUR
T1 - Role of macrophage migration inhibitory factor in age-related hearing loss
AU - Kariya, S.
AU - Okano, Mitsuhiro
AU - Maeda, Y.
AU - Hirai, H.
AU - Higaki, T.
AU - Noyama, Y.
AU - Haruna, T.
AU - Nishihira, J.
AU - Nishizaki, Kazunori
N1 - Funding Information:
This work was supported by JSPS KAKENHI (Grants-in-Aid for Scientific Research from The Ministry of Education, Culture, Sports, Science and Technology of Japan; grant number, 23791900 and 25462642 ).
Publisher Copyright:
© 2014 IBRO.
PY - 2014/9/4
Y1 - 2014/9/4
N2 - Hearing loss related to aging is the most common sensory disorder among elderly individuals. Macrophage migration inhibitory factor (MIF) is a multi-functional molecule. The aim of this study was to identify the role of MIF in the inner ear. MIF-deficient mice (MIF-/- mice) of BALB/c background and wild-type BALB/c mice were used in this study. Expression of MIF protein in the inner ear was examined by immunohistochemistry in wild-type mice (WT). The hearing function was assessed by the click-evoked auditory brainstem response in both MIF-/- mice and WT at 1, 3, 6, 9, 12, and 18months of age. Morphological examination of the cochlea was also performed using scanning electron microscopy and light microscopy. MIF was observed in the spiral ligament, stria vascularis, Reissner's membrane, spiral ganglion cells (SGCs), saccular macula, and membranous labyrinth. The MIF-/- mice had a significant hearing loss as compared with the WT at 9, 12, and 18months of age. In the MIF-/- mice, scanning electron microscopy showed that the outer cochlear hair cells were affected, but that the inner cochlear hair cells were relatively well preserved. The number of SGCs was lower in the MIF-/- mice. MIF was strongly expressed in the mouse inner ear. Older MIF-/- mice showed accelerated age-related hearing loss and morphological inner ear abnormalities. These findings suggest that MIF plays an important role in the inner ear of mice.
AB - Hearing loss related to aging is the most common sensory disorder among elderly individuals. Macrophage migration inhibitory factor (MIF) is a multi-functional molecule. The aim of this study was to identify the role of MIF in the inner ear. MIF-deficient mice (MIF-/- mice) of BALB/c background and wild-type BALB/c mice were used in this study. Expression of MIF protein in the inner ear was examined by immunohistochemistry in wild-type mice (WT). The hearing function was assessed by the click-evoked auditory brainstem response in both MIF-/- mice and WT at 1, 3, 6, 9, 12, and 18months of age. Morphological examination of the cochlea was also performed using scanning electron microscopy and light microscopy. MIF was observed in the spiral ligament, stria vascularis, Reissner's membrane, spiral ganglion cells (SGCs), saccular macula, and membranous labyrinth. The MIF-/- mice had a significant hearing loss as compared with the WT at 9, 12, and 18months of age. In the MIF-/- mice, scanning electron microscopy showed that the outer cochlear hair cells were affected, but that the inner cochlear hair cells were relatively well preserved. The number of SGCs was lower in the MIF-/- mice. MIF was strongly expressed in the mouse inner ear. Older MIF-/- mice showed accelerated age-related hearing loss and morphological inner ear abnormalities. These findings suggest that MIF plays an important role in the inner ear of mice.
KW - Cochlea
KW - Ear
KW - Hair cell
KW - Hearing loss
KW - Macrophage migration inhibitory factor
KW - Spiral ganglion cells
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U2 - 10.1016/j.neuroscience.2014.08.042
DO - 10.1016/j.neuroscience.2014.08.042
M3 - Article
C2 - 25194790
AN - SCOPUS:84907567150
SN - 0306-4522
VL - 279
SP - 132
EP - 138
JO - Neuroscience
JF - Neuroscience
ER -