Protective Effect by 15D-PGJ2 Against Oxidative Damage to Mouse Cochlear Spiral Ganglion

LUO Yan; CAO Zhongsheng; ZHU Zhengwen; YUAN Hui

doi:10.3969/j.issn.1672-2922.2015.01.012

Abstract：Objective To evaluate the protective effects by PPAR gamma agonist 15D-PGJ2 against hydrogen perox?ide (H2O2)-induced oxidative damage to auditory nerve fibers in an in vitro model. Method Cochlear basilar membranes from mice of postnatal day 3 were cultured for 24 h and subjected to 24 h treatment of H2O2 (3 mM, 6 mM), with or without 24 h pretreatment with various concentrations of PPAR gamma agonist 15D-PGJ2 (10μM, 30μM) and followed by H2O2 treat?ment for 24 h, respectively. Auditory nerve fibers from spiral ganglion neurons projecting to the organ of Corti were labeled with neurofilament-200 via immunohistochemistry and quantified for evaluation of surviving auditory nerve fibers. The data were statistically analyzed. Results The auditory nerve fibers from spiral ganglion neurons appeared normal in the control group. In contrast, intact nerve fibers were significantly reduced by H2O2 treatment in a dose dependent manner. When cochle?ar explants were pretreated with 15D-PGJ2 before H2O2 treatment for 24 h, surviving auditory nerve fibers were significantly increased, suggesting strengthened protective effects by increasing 15D-PGJ2 concentration against H2O2. Conclusion PPAR gamma agonist 15D-PGJ2 can protect auditory nerve fibers from spiral ganglion neurons against H2O2 damage in mice.