Physiological Significance of p62-mediated Autophagy in Auditory Cells

Objectives:Elucidate how Keap1, Nrf2 and p62 provide molecular foundation for a possible crosstalk between autophagy and necrosis pathways in auditory cells.Methods:We used auditory cell line HEI-OC1 in this study. The viability of HEI-OC1 was determined by cell viability assays. The samples after treatment of HEI-OC1 were analyzed by a flow cytometer. Immunofluorescent confocal laser microscopy was used. Western blot was performed. Morphological observation was performed by transmission electron microscope (TEM). Transient GFP-LC3 and p62 siRNA were transfected into HEI-OC1 with electroporation.Results:HEI-OC1 treated with H2O2 exhibited dose- and time-dependent cell death. After treatment of H2O2, not apoptotic cell but necrotic cell was detected by a flow cytometer. H2O2 treatment resulted in time-dependent accumulation of LC3-II and the expression of GFP-LC3 in HEI-OC1 cells. Autophagosomes were confirmed under TEM in H2O2 treated-HEI-OC1. Immunostaining analysis demonstrated that the majority proport...