Acoustic Trauma Modulates Cochlear Blood Flow and Vasoactive Factors in a Rodent Model of Noise-Induced Hearing Loss.
Sun-Ae ShinAh-Ra LyuSeong-Hun JeongTae Hwan KimMin Jung ParkYong-Ho ParkPublished in: International journal of molecular sciences (2019)
Noise exposure affects the organ of Corti and the lateral wall of the cochlea, including the stria vascularis and spiral ligament. Although the inner ear vasculature and spiral ligament fibrocytes in the lateral wall consist of a significant proportion of cells in the cochlea, relatively little is known regarding their functional significance. In this study, 6-week-old male C57BL/6 mice were exposed to noise trauma to induce transient hearing threshold shift (TTS) or permanent hearing threshold shift (PTS). Compared to mice with TTS, mice with PTS exhibited lower cochlear blood flow and lower vessel diameter in the stria vascularis, accompanied by reduced expression levels of genes involved in vasodilation and increased expression levels of genes related to vasoconstriction. Ultrastructural analyses by transmission electron microscopy revealed that the stria vascularis and spiral ligament fibrocytes were more damaged by PTS than by TTS. Moreover, mice with PTS expressed significantly higher levels of proinflammatory cytokines in the cochlea (e.g., IL-1β, IL-6, and TNF-α). Overall, our findings suggest that cochlear microcirculation and lateral wall pathologies are differentially modulated by the severity of acoustic trauma and are associated with changes in vasoactive factors and inflammatory responses in the cochlea.
Keyphrases
- blood flow
- hearing loss
- high fat diet induced
- poor prognosis
- electron microscopy
- air pollution
- minimally invasive
- rheumatoid arthritis
- randomized controlled trial
- induced apoptosis
- genome wide
- wild type
- gene expression
- insulin resistance
- long non coding rna
- endothelial cells
- cell proliferation
- dna methylation
- drug induced
- cell cycle arrest
- clinical trial
- study protocol
- cerebral ischemia
- bioinformatics analysis
- double blind