The Contribution of Anti-oxidant and Anti-inflammatory Functions of Adenosine A1 Receptor in Mediating Otoprotection
The production of high levels of adenosine into the extracellular fluid during enhanced metabolic activity or ischemic conditions confers cytoprotection to the affected tissue. This action is mediated by adenosine receptors (ARs) which are ubiquitously expressed on the surface of cells which respond to the elevation in levels of adenosine in the extracellular fluid. While endogenous adenosine released to the extracellular fluid could confer protection under normal physiological condition, exogenously administered adenosine analogs are required to boost the protective capacity of these receptors under stress conditions. This chapter provides a summary of the adenosine/AR system in the cochlea and shows that the adenosine A1 receptor (A1AR) could protect against hearing loss by inhibiting cochlear oxidative stress, inflammation and apoptosis of cochlear cells.
KeywordsAdenosine A1 receptor Hearing loss Oxidative stress Cochlear inflammation Otoprotection
The authors would like to acknowledge NIH grant support: NCI RO1 CA166907 to VR, NIDCD RO1-DC 002396 to LPR and RO3 DC011621 to DM, and a grant from the American Hearing Research Foundation to SS.
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