Процедуры гипоксического кондиционирования не приводят к чрезмерной активации оксидативного стресса у практически здоровых обследуемых

Abstract

Hypoxic conditioning (HC) in the mode of interval hypoxic training has therapeutic and prophylactic effects. Reactive oxygen species (ROS) play an important role in the realization of these effects. However, the impacts of different HC protocols on the induction of oxidative stress are still under discussion. Using the FRAS-5 photometric system, 24 healthy men have been assessed for ROS concentration (d-ROM index), plasma antioxidants test (PAT), and the oxidative stress index (OSI) before and after each of two following procedures: interval hypoxic-normoxic (IHNT) and interval hypoxic-hyperoxic (IHHT) training. HC protocol: breathing through the facial mask with a hypoxic gas mixture (10% O2) for 4–6 minutes, then breathing by atmospheric air (IHNT) or by hyperoxic mixture (35% O2 - IHHT) for 1.5–2 minutes; total single procedure’s duration - 40–45 minutes. No reliable average group changes in the parameters of d-ROM and PAT were registered after both HC protocols. But in each case, a significant inter- and intra-individual variability was observed. Most of the examined parameters after HC remained in the ranges of normal or boundary values. A significant positive correlation was registered between the degree of individual hypoxic resistance, measured as blood desaturation (Delta SaO2), and the increase in PAT. Also, a negative relationship was found between Delta SaO2 and the degree of OSI increase. Both of these correlations were registered after IHHT, but not after IHNT. Conclusion: single IHNT and IHHT do not induce pronounced oxidative stress in most of the healthy volunteers; however, HC treatments were accompanied by changes in d-ROM and PAT, which may reflect the activation of redox signaling pathways. In subjects who are more resistant to hypoxia, IHHT leads to a more significant increase in antioxidant potential and a decrease of OSI. The results confirm the safety of IHNT and IHHT applications. Monitoring of pro- / antioxidant status based on FRAS-5 markers may be informative for individual selection of adaptation protocols to interval hypoxia.