Bisphenol A induces ototoxic injury by ferroptosis pathway: integrated analysis of network toxicology, RNA-sequencing...

Bisphenol A, a globally utilized plastic monomer, has extensively infiltrated aquatic and atmospheric environments, emerging as a high-priority environmental pollutant. However, its toxicological impact on ototoxic injury and the associated molecular mechanisms remain largely unexplored. In this study, we employed an integrative approach combining network toxicology, RNA sequencing, and cellular phenotyping to systematically elucidate the pathways of Bisphenol A-induced injury. Potential ototoxicity-related targets and Bisphenol A-binding proteins were sourced from databases such as BindingDB, CTD, SwissTargetPrediction, TargetNet, DisGeNET, and GeneCards, resulting in the identification of 55 candidate targets. Functional enrichment analysis revealed significant involvement in autophagy and HIF-1 signaling pathways, while multi-algorithm topology analysis identified CASP3, PTGS2, CYCS, BCL2, TNF, PPARG, NFE2L2, and MAPK3 as key hub proteins. Experimental validation demonstrated that Bisphenol A reduced cell viability and increased lactate dehydrogenase leakage in a concentration-dependent manner. RNA sequencing further revealed a marked activation of the ferroptosis pathway following Bisphenol A exposure. Ferroptotic cell death was further corroborated by increased levels of lipid reactive oxygen species, malondialdehyde, and intracellular Fe²⁺, accompanied by the down-regulation of GPX4, SLC3A2, and FSP-1 expression, as well as the up-regulation of ACSL4, PTGS2, and HO-1 expression. Collectively, our findings indicate that Bisphenol A induces ototoxic injury via the ferroptosis pathway, suggesting that this environmental contaminant may contribute to hearing loss and highlighting potential interventions against Bisphenol A exposure.