Intermittent Hypoxia Research in the Former Soviet Union and the Commonwealth of Independent States: History and Review of the Concept and Selected Applications

Abstract

This review aims to summarize the basic research in the field of intermittent hypoxia in the Soviet Union and the Commonwealth of Independent States (CIS) that scientists in other Western countries may not be familiar with, since Soviet scientists were essentially cut off from the global scientific community for about 60 years. In the 1930s the concept of repeated hypoxic training was developed and the following induction methods were utilized: repeated stays at high-mountain camps for several weeks, regular high altitude flights by plane, training in altitude chambers, and training by inhalation of low-oxygen-gas mixtures. To the present day, intermittent hypoxic training (IHT) has been used extensively for altitude preacclimatization; for the treatment of a variety of clinical disorders, including chronic lung diseases, bronchial asthma, hypertension, diabetes mellitus, Parkinson's disease, emotional disorders, and radiation toxicity, in prophylaxis of certain occupational diseases; and in sports. The basic mechanisms underlying the beneficial effects of IHT are mainly in three areas: regulation of respiration, free-radical production, and mitochondrial respiration. It was found that IHT induces increased ventilatory sensitivity to hypoxia, as well as other hypoxia-related physiological changes, such as increased hematopoiesis, alveolar ventilation and lung diffusion capacity, and alterations in the autonomic nervous system. Due to IHT, antioxidant defense mechanisms are stimulated, cellular membranes become more stable, Ca(2+) elimination from the cytoplasm is increased, and O(2) transport in tissues is improved. IHT induces changes within mitochondria, involving NAD-dependent metabolism, that increase the efficiency of oxygen utilization in ATP production. These effects are mediated partly by NO-dependent reactions. The marked individual variability both in animals and humans in the response to, and tolerance of, hypoxia is described. Studies from the Soviet Union and the CIS significantly contributed to the understanding of intermittent hypoxia and its possible beneficial effects and should stimulate further research in this direction in other countries.

Spinal Synaptic Enhancement with Acute Intermittent Hypoxia Improves Respiratory Function after Chronic Cervical Spinal Cord Injury

“…Quadriplegics are unable to exercise appreciably, and, unlike intensive physical therapy, acute intermittent hypoxia is easy to apply and carries minimal risk, because only a small number of mild to moderate hypoxic episodes are required for an enduring effect on respiratory motor output (Powell and Garcia, 2000;Serebrovskaya, 2002). Furthermore, because of progress made toward understanding the cellular mechanisms of pLTF (Baker-Herman et al, 2004;Bocchiaro and Feldman, 2004), it may be possible to intervene downstream from intermittent hypoxia and serotonin release, bypassing practical limits in the use of intermittent hypoxia during the acute phase of SCI.…”

Hypoxic training: Clinical benefits on cardiometabolic risk factors

“…Research into the use hypoxic training initiated in the former Soviet Union as early as the 1940s and since then, there were numerous publications [43]. Unfortunately, most of these studies are published in Russian and hence, excluded from this review.…”

Response of Skeletal Muscle Mitochondria to Hypoxia

“…In particular, these types of interventions have not to our knowledge been analysed with regard to changes of the mitochondrial compartment. This literature will thus not be reviewed here (see Serebrovskaya, 2002). We also recognize that hypoxaemia (combined with hypercapnia) in humans often results from lung disease such as chronic obstructive pulmonary disease (COPD).…”