Individual Responses to Physical Activity: Study of the Salivary Extracellular Vesicles

Individual responses to physical activity: study of the salivary extracellular vesicles S. Fondi1, R Agostini1, L. Giacomelli1, P Ceccaroli1, E Polidori1, M Guescini1. 1Department of Biomolecular Sciences, University of Urbino Carlo Bo, 61029 Urbino, Italy Background: It is well known that regularly performed exercise improves muscle endurance through the stimulation of mitochondrial biogenesis. This notion is very well recognized in the context of athletic performance, while the effect that exercise has on muscle metabolism during aging or disease conditions when mitochondrial function is compromised has still to be fully investigated. Aim: The present project aims to identify new exercise biomarkers using saliva, an accessible biological fluid. Methods: Saliva samples were collected from athletes pre- and post-exercise and then processed by serial ultracentrifugation to isolate EVs. The samples were characterized by NTA analysis to measure EV size distribution and concentration, and BCA assay was performed for total protein content. Finally, Dot Blot assay was employed for the antibody-based detection of the EV markers proteins CD63 and HSP60. Preliminary Results: NTA analysis showed typical EV size and distribution; interestingly, Dot Blot assay assessed the highest CD63 and HSP60 positivity in most samples at 15 hours post-exercise. Conclusions: salivary extracellular vesicles could represent an innovative source of exercise biomarkers that would allow the development of standardized exercise protocols based on individual responses to physical activity.