Exploratory multi-biofluid proteomic profiling of acute exercise responses in plasma, tear fluid, and nasal secretions.

BACKGROUND

Exercise induces broad physiological adaptations through complex molecular regulation across multiple biological systems. While plasma-based proteomics has substantially advanced our understanding of exercise-associated molecular changes, the proteomic responses of mucosal biofluids, including tear fluid and nasal secretions, remain poorly characterized. A multi-biofluid proteomic approach may provide a more comprehensive characterization of molecular alterations associated with acute exercise.

METHODS

Paired samples of plasma, tear fluid, and nasal secretions were collected from five young, healthy female participants before and after acute aerobic exercise and analyzed using data-independent acquisition (DIA) liquid chromatography-tandem mass spectrometry (LC-MS/MS). Proteomic profiles across the three biofluids were characterized, and joint mixed-effects modeling was performed to identify proteins exhibiting common or biofluid-specific exercise-associated responses. Functional enrichment analyses were conducted to characterize the functional categories associated with upregulated and downregulated proteins in each biofluid.

RESULTS

Highly abundant proteins shared across the three biofluids showed enrichment in immune-related processes, inflammatory responses, and protease regulation. Joint mixed-effects analysis identified proteins exhibiting common exercise-associated responses across biofluids, which were primarily enriched in translation-related proteins, including ribosomal proteins, as well as proteins showing biofluid-specific exercise-associated responses. Acute exercise induced differential proteomic alterations across the three biofluids, with differentially abundant proteins showing distinct functional enrichment patterns among the three biofluids.

CONCLUSION

This study provides a multi-biofluid DIA proteomic characterization of acute exercise-associated molecular alterations. The findings demonstrate that exercise-induced proteomic changes differ across plasma, tear fluid, and nasal secretions, highlighting the value of integrating multiple biofluids to characterize molecular responses associated with exercise. These results provide a foundation for future studies involving larger cohorts and targeted validation.