The purified EVs were resuspended in pre-cooled PBS, aliquoted into 2 mL low-adsorption centrifuge tubes, and processed in triplicate. Protein concentration was quantified using the BCA method to ensure that each sample contained at least 200 μg/mL protein. Subsequent analyses were performed by Shanghai Zhongke Xinshengsheng Biotechnology Co., Ltd., according to the following standardized procedures: (1) protein lysis followed by reduction, alkylation, and tryptic digestion; (2) separation and mass spectrometry detection using LC-MS/MS (Q-Exactive HF-X, Thermo); (3) database searching against Lactobacillus plantarum (UniProt) using MaxQuant (v1.6.17) with an FDR threshold of 1%; (4) differentially expressed proteins identification using Perseus, and functional annotations and pathway analysis via Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG).