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

Abstract

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.