DataSheet_1_Multi-omics analysis reveals the effects of microbiota on oral homeostasis.docx

The oral epithelium’s normal morphological structure and function play an important role in maintaining oral homeostasis, among which microbiota and chronic stress are key contributing factors. However, the effects of microbiota and chronic stress on the morphological structures and molecular function of oral homeostasis remain unclear. In this study, morphological staining was used to compare the tongue structure of specific pathogen-free and germ-free mice, and an integrated multi-omics analysis based on transcriptomics, proteomics, and metabolomics was performed to investigate the regulatory mechanisms of microbiota and chronic stress on oral homeostasis. We found that the morphological structure of the tongue in germ-free mice was disordered compared with in specific pathogen-free mice, especially in the epithelium. Multi-omics analysis indicated that differentially expressed molecules of the tongue between germ-free and specific pathogen-free mice were significantly enriched in the mitochondrial metabolic process and immune response. Interestingly, microbiota also significantly influenced the permeability of the oral epithelial barrier, represented by the differential expression of keratinization, and cell adhesion molecules. It was worth noting that the above changes in the tongue between specific pathogen-free and germ-free mice were more significant after chronic stress. Collectively, this is the first study to reveal that the microbiota might maintain oral homeostasis by reshaping the structure of the oral epithelial barrier and changing the function of molecular biology, a process that may be driven by the immune response and mitochondrial metabolic process of oral tissue. Furthermore, chronic stress can enhance the regulatory effects of microbiota on oral homeostasis.

口腔上皮（oral epithelium）的正常形态结构与功能在维持口腔稳态（oral homeostasis）中发挥重要作用，其中微生物群（microbiota）与慢性应激（chronic stress）是关键的影响因素。然而，微生物群与慢性应激对口腔稳态相关形态结构及分子功能的调控效应仍尚不明确。本研究采用形态学染色技术对比无特定病原体（specific pathogen-free）小鼠与无菌小鼠（germ-free mice）的舌部结构，并基于转录组学（transcriptomics）、蛋白质组学（proteomics）与代谢组学（metabolomics）开展整合多组学分析，以探究微生物群与慢性应激对口腔稳态的调控机制。研究发现，与无特定病原体小鼠相比，无菌小鼠的舌部形态结构出现紊乱，尤以上皮层为甚。多组学分析显示，无菌小鼠与无特定病原体小鼠舌部的差异表达分子显著富集于线粒体代谢过程与免疫应答通路。有趣的是，微生物群还可显著影响口腔上皮屏障的通透性，其表现为角质形成（keratinization）与细胞黏附分子（cell adhesion molecules）的差异表达。值得注意的是，经慢性应激处理后，无特定病原体小鼠与无菌小鼠舌部的上述差异变化更为显著。综上，本研究首次揭示：微生物群可通过重塑口腔上皮屏障结构、调控口腔组织分子生物学功能以维持口腔稳态，该过程可能由口腔组织的免疫应答与线粒体代谢过程所驱动。此外，慢性应激可增强微生物群对口腔稳态的调控作用。