Hypoxic preconditioning - a non-pharmacological approach in COVID-19 prevention.

Hypoxia is defined by low oxygen concentration in organs, tissues and cells. Maintaining oxygen homeostasis represents the essential cellular metabolic process for the structural integrity of tissues in different pathological conditions, including SARS-CoV-2 infection. Considering the role of hypoxia-inducible factor-1 (HIF-1) as regulator of cellular response to hypoxia and its involvement in angiogenesis, erythropoiesis, glucose metabolism, inflammation, we propose hypoxic preconditiong (HPC) as a novel prevention therapeutic approach on healthy contacts of COVID-19 patients. To date, several studies revealed the benefic effects of hypoxic preconditioning in ischemia, kidney failure and in pulmonary function recovery of lung surgery patients. HPC increases the expression of factors that promote cell survival and angiogenesis, induces an anti-inflammatory outcome, triggers coordinated hypoxia responses that promote erythropoiesis, and mobilizes the circulating progenitor cells. Futhermore, the mesenchymal stem cells (MSC) exposed to HPC show improvement of their regenerative capacities, and increases the effectiveness of stem cell therapy in different pathologies, including COVID-19. In conclusion, HPC should be considered an approach with beneficial outcomes and without significant side effects when the organism is severely exposed to the same stressor. HPC appears as a trigger to mechanisms that improve and maintain tissue oxygenation and repair, a main goal in different pathologies, including COVID-19 or other respiratory conditions.