Article

The mechanisms of central auditory processing involved in auditory/vestibular
injuries and subsequent tinnitus and hearing loss in Active Duty servicemembers
exposed to blast are not currently known. We analyzed the expression of
hearing-related genes in different regions of the brain 6 h after repeated blast
exposures in mice. Preliminary data showed that the expression of the
deafness-related genes otoferlin and otoancorin was significantly changed in the
hippocampus after blast exposures. Differential expression of cadherin and
protocadherin genes, which are involved in hearing impairment, was observed in
the hippocampus, cerebellum, frontal cortex, and midbrain after repeated blasts.
A series of calcium-signaling genes that are known to be involved in auditory
signal processing were also found to be significantly altered after repeated
blast exposures. The hippocampus and midbrain showed significant increase in the
gene expression of hearing loss-related antioxidant enzymes. Histopathology of
the auditory cortex showed more significant injury in the inner layer compared to
the outer layer. In summary, mice exposed to repeated blasts showed injury to the
auditory cortex and significant alterations in multiple genes in the brain known
to be involved in age- or noise-induced hearing impairment.

Langue : ANGLAIS