Effects of a 6-wk Sprint Interval Training Protocol at Different Altitudes on Circulating Extracellular Vesicles

Abstract

PurposeThis study aimed to investigate the modulation of circulating exosome-like extracellular vesicles (ELVs) after 6 wk of sprint interval training (SIT) at sea level and at 2000, 3000, and 4000 m.MethodsThirty trained endurance male athletes (18–35 yr) participated in a 6-wk SIT program (30-s all-out sprint, 4-min 30-s recovery; 4–9 repetitions, 2 sessions per week) at sea level (n = 8), 2000 m (fraction of inspired oxygen (Fio2) 0.167, n = 8), 3000 m (Fio2 0.145, n = 7), or 4000 m (Fio2 0.13, n = 7). Venous blood samples were taken before and after the training period. Plasma ELVs were isolated by size exclusion chromatography, counted by nanoparticle tracking analysis, and characterized according to international standards. Candidate ELV microRNAs (miRNAs) were quantified by real-time polymerase chain reaction.ResultsWhen the three hypoxic groups were analyzed separately, only very minor differences could be detected in the levels of circulating particles, ELV markers, or miRNA. However, the levels of circulating particles increased (+262%) after training when the three hypoxic groups were pooled, and tended to increase at sea level (+65%), with no difference between these two groups. A trend to an increase was observed for the two ELV markers, TSG101 (+65%) and HSP60 (+441%), at sea level, but not in hypoxia. Training also seemed to decrease the abundance of miR-23a-3p and to increase the abundance of miR-21-5p in hypoxia but not at sea level.ConclusionsA 6-wk SIT program tended to increase the basal levels of circulating ELVs when performed at sea level but not in hypoxia. In contrast, ELV miRNA cargo seemed to be modulated in hypoxic conditions only. Further research should explore the potential differences in the origin of ELVs between normoxic and local and systemic hypoxic conditions.

The separation and identification of circulating small extracellular vesicles from endurance‐trained, strength‐trained and recreationally active men

“…In humans, recent studies investigated whether 12 weeks of resistance exercise training (Xhuti et al., 2023) or 6 weeks of sprint interval training (SIT) (Warnier et al., 2023) altered the presence of small EVs in blood samples taken at rest. The first of these studies observed that a home‐based resistance exercise training intervention (progressive elastic band‐based resistance exercise; 3 days per week) did neither alter the abundance of five EV marker proteins (ALIX, CD63, TSG101, CD9, CD81) nor the size and number of particles in the small EV size range in plasma from older adults taken at ∼96 h after their most recent exercise session (Xhuti et al., 2023).…”

“…The first of these studies observed that a home‐based resistance exercise training intervention (progressive elastic band‐based resistance exercise; 3 days per week) did neither alter the abundance of five EV marker proteins (ALIX, CD63, TSG101, CD9, CD81) nor the size and number of particles in the small EV size range in plasma from older adults taken at ∼96 h after their most recent exercise session (Xhuti et al., 2023). In the second of these studies, endurance‐trained men completed 18 sessions (two sessions per week for 9 weeks) of SIT at either sea level or 2000, 3000 or 4000 m of simulated altitude in the form of normobaric hypoxia (Warnier et al., 2023). There was no effect of exercise training at sea level, but SIT in hypoxia resulted in an increase in the number of particles in the small EV size range (assessed via NTA) in plasma taken at ∼72 h after their last exercise training session (Warnier et al., 2023).…”

“…In the second of these studies, endurance‐trained men completed 18 sessions (two sessions per week for 9 weeks) of SIT at either sea level or 2000, 3000 or 4000 m of simulated altitude in the form of normobaric hypoxia (Warnier et al., 2023). There was no effect of exercise training at sea level, but SIT in hypoxia resulted in an increase in the number of particles in the small EV size range (assessed via NTA) in plasma taken at ∼72 h after their last exercise training session (Warnier et al., 2023). Of note is that the increase observed in hypoxia was significant only when participants from all three hypoxia conditions were pooled ( n = 22), and no differences were observed in the abundance of four EV marker proteins (CD81, CD9, TSG101, HSP60).…”

Molecular insights of exercise therapy in disease prevention and treatment

“… 60 , 61 Importantly, non-coding RNAs are cell type-specific 62 , 63 but can also exert their functions in other cell types via paracrine and/or endocrine signaling through extracellular vesicles (EVs). 64 – 66 …”

The effects of extracellular vesicles and their cargo on metabolism and its adaptation to physical exercise in insulin resistance and type 2 diabetes

“…However, sEV isolated from plasma of rowers show elevated systemic miR‐342‐5p concentrations and cardioprotective effects, such as reduced LDH release and cardiomyocyte apoptosis, when injected in human cardiomyocytes subjected to ischemia/reperfusion injury [188]. In contrast, 6‐w SIT enhances the number of circulating EV and the levels of miR‐21‐5p, but decreases miR‐23a‐3p levels under hypoxic conditions [189]. A supervised interval or continuous training for 2 weeks does not alter the number of platelet or leukocytes derived EV in obese adults with prediabetes, whereas dietary sugar intake after training increases the number of endothelial EV, which correlates with improved VO 2max [190].…”