Pioglitazone ameliorates gentamicin ototoxicity by affecting the TLR and STAT pathways in the early postnatal organ of Corti

We evaluated the effects of pioglitazone in mouse organ of Corti (OC) explants to characterize its influence on signaling pathways involved in auditory hair cell damage. Organ of Corti explants were cultured with pioglitazone, gentamicin, or a combination of both agents. Pioglitazone treatment resulted in a significant repression of interferon (IFN)-alpha and -gamma pathways and downstream cytokines, as assessed by RNA sequencing and quantitative PCR gene expression assays. More detailed investigation at the single gene and protein level showed that pioglitazone mediated its anti-inflammatory effects through alterations of the Toll-like receptor (TLR) and STAT pathways. Together, these results indicate that pioglitazone significantly represses IFN and TLR in the cochlea, dampening the activity of gentamicin-induced pathways. These data support our previous results demonstrating significant protection of auditory hair cells in organ of Corti explants exposed to pioglitazone and other PPAR-targeted agents. Overall design: Examination of pioglitazone, gentamicin or combined treatment effects on signalling pathway changes in the early postnatal wild type Organ of Corti explants.