Salivary Proteome–Microbiome Profiling in Burning Mouth Syndrome Might Highlight Mucin‐Related Host–Microbe Features

OBJECTIVE: This pilot study was designed to analyze salivary proteomic and microbiome profile in burning mouth syndrome (BMS) and to explore the potential role of salivary mucins in barrier-related host-microbe interactions. METHODS: Unstimulated saliva samples from BMS patients and healthy controls were analyzed using data-independent acquisition (DIA)-based proteomics and 16S rRNA gene sequencing. A multi-step strategy was applied to identify BMS-associated core salivary proteins. Biofilm formation, epithelial adhesion and injury, as well as molecular permeability using a transwell model were conducted to assess the mucosal barrier-microbe interactions. RESULTS: Proteomic profiling defined 29 BMS-associated core proteins with MUC5B showing prominent differential expression. Microbiome analysis showed altered community structure in BMS saliva, including increased relative abundance of Rothia. Further in vitro explorations revealed that mucin triggered dispersal of the formed biofilms, reduced bacterial adhesion to oral epithelial cells, attenuated epithelial cell injury and decreased FITC-dextran permeability in a concentration-dependent manner. CONCLUSION: BMS might be associated with mucin-related alterations in the salivary microenvironment, including reduced MUC5B and increased relative abundance of Rothia. Together with the in vitro findings, this might suggest that mucin-related barrier changes may be linked to altered host-microbe interactions in BMS.