Mitochondria as a key target of molecular hydrogen

Abstract

The aim of the work was to systematize the data on the biologically significant effects of molecular hydrogen to uncover the mechanisms of its effect on the human body. The paper analyzes the literature on the effect of molecular hydrogen administered in the form of inhalation and hydrogenenriched water on the human body, on laboratory mammals (rats, mice), and on model cell systems in vitro. As a result, a mechanism has been proposed according to which, in addition to the already known effect of hydrogen in neutralizing highly reactive oxygen species, there is at least one other group of molecules that are the target of molecular hydrogen in the body. These are the porphyrins, which are part of the hemoproteins, in particularly the cytochromes of the mitochondrial respiratory chain. In the presence of high concentrations of carbon dioxide, which is formed in the tricarboxylic acid cycle in the mitochondrial matrix, hydrogen damages some of the hemes as a result of covalent binding of the CO group to them. At low doses of hydrogen, this causes a moderate decrease in mitochondrial potential and stimulates the adaptive response of the body, including activation of the transcription factor Nrf2, expression of the heme oxygenase and antioxidant defense enzymes, mitophagy, and renewal of the mitochondrial population in the cell.Conclusion. Molecular hydrogen is an adaptogen that causes mitochondrial hormesis – the renewal and strengthening of the body’s bioenergetic and antioxidant systems.