Dual-Omics Mapping of Tinnitus Phenotype Transition in Noise-Exposed Auditory Cortex

Noise-induced hearing loss (NIHL) is a primary contributor to tinnitus, involving mechanisms such as inflammatory damage, central sensitization, and auditory cortex remodeling. However, not all cases of tinnitus are accompanied by NIHL, and the precise relationship between the two remains incompletely understood. Phosphorylation/dephosphorylation, as a core mechanism for fine cellular regulation, influences neuronal excitability, immune responses, and disease development by modulating protein activity, signal transduction, and gene expression. We hypothesized that aberrant phosphorylation levels may alter auditory cortex neuron function, leading to pathological changes at the protein level. Leveraging auditory cortex tissue from a noise-induced tinnitus model, we systematically investigated the pathogenesis of tinnitus and its distinction from NIHL through integrated proteomic and phosphoproteomic analyses. Compared to animals with NIHL alone, the tinnitus model exhibited enhanced neuronal excitability, synaptic dysfunction, hyperactive energy metabolism, and weakened neuroprotection, with disordered membrane receptor function playing a critical role. Multi-omics analysis further revealed that tinnitus development primarily depends on phosphorylation-mediated post-translational modifications reshaping cellular function, rather than changes in protein abundance caused by alterations in gene transcription levels. Collectively, this study elucidates the physiological and cellular structural alterations in noise-induced tinnitus from the dimensions of protein expression and phosphorylation modification. It confirms that tinnitus leads to neural dysfunction through abnormal membrane receptor activity, and the characteristic proteins and phosphorylation sites identified offer novel therapeutic targets for modulating central hyperexcitability in tinnitus. Integrated proteomics and phosphoproteomics of auditory cortex tissue reveals that noise-induced tinnitus pathogenesis fundamentally diverges from noise-induced hearing loss (NIHL), critically depending on phosphorylation-mediated functional reprogramming rather than transcriptional-level protein abundance changes. Tinnitus models exhibit pathological neural hyperexcitability and synaptic dysfunction driven by disordered membrane receptor activity, alongside hyperactive energy metabolism and weakened neuroprotection. Crucially, spatiotemporal phospho-dynamics—not protein expression—reshape cellular function through post-translational remodeling, with multi-omics analysis confirming that tinnitus development is governed by site-specific phosphorylation networks. This phospho-centric mechanism explains the inefficacy of single-target therapies against distributed network perturbations and presents characteristic phosphosites/proteins as novel targets for modulating central hyperexcitability, offering multi-target intervention strategies to restore phospho-network homeostasis.