Horse extracellular particle miRNAs

Physical exercise is an essential factor to prevent and treat metabolic diseases by promoting systemic benefits through the body. Extracellular vesicles (EVs) can transport proteins and miRNAs in the bloodstream which can participate in the benefits of exercise to health. Horses endurance riding is an excellent model to study the impact of long-duration exercise in plasma EVs and plasma EVs miRNAs. Here, we purified plasma from 5 Arabian horses during five-time points of an endurance race. Extracellular particles (Eps) were purified from plasma and characterized by immunoelectron microscopy, resistive pulse sensing (qNano) and western blotting. Small RNAs were purified from horse’s plasma EPs, and miRNAs library and sequencing were performed. Endurance riding increased EPs concentration and average diameter compared to before the race. Western blotting showed a high concentration of exosomes after 2h of the race, which returned to baseline 15h after the race. MicroRNA sequencing revealed 291 miRNAs downregulated in horse’s plasma EPs miRNAs 15h after the race. In silico analysis predicted that these miRNAs could be involved in the regulation of endocytosis pathway as well as lipid metabolism and biosynthesis. This study adds new data about the fluctuation of plasma EPs concentration after long-distance exercise and brings new insights about the roles of exercise derived EPs miRNAs in target tissues.