Hypoxia, reducing the activity of the main source of free energy – the mitochondrial system of oxidative phosphorylation, leads to a decrease in both phosphate and redox potential of cells. The unique property of hypoxia as the main pathogenic factor causing aging is the presence of numerous enhancers of its action. First, a decrease in oxygen concentration leads to a decrease in the rate of free energy production in the cell, the main mass carriers of which are ATP, NADH, NADPH and gradients of hydrogen, sodium, potassium and chlorine ions on cell membranes.

Cells contain more than 500 NADH- and NADPH-dependent enzymes (dehydrogenases), which, due to the free energy of oxidation of pyridine nucleotides, direct cell metabolism. Also in cells there are more than 200 ATP hydrolases that catalyze reactions that require the supply of free energy for their course. In the plasma membranes of various cells, there are energy-dependent translocases, which, due to the energy of the sodium cation gradient, provide the transport of a large list of metabolites into the cell against their concentration gradients.

Secondly, a decrease in the partial pressure of oxygen in organs and tissues leads to a decrease in the enzymatic activity of a number of oxidases. With a decrease in the activity of even one of the oxidases, important metabolic consequences arise in almost all organs and tissues.

A decrease in the activity of such a huge amount of enzymes under conditions of hypoxia leads to the most catastrophic consequences for cells, causing their death and death of the body.

At the physiological level, with aging, there is also a decrease in the production capacity of carriers of free energy due to a decrease in the supply of oxygen to organs and tissues, due to a decrease in the functions of the respiratory and cardiovascular systems.

The situation is aggravated by the fact that the carriers of free energy and their derivatives (cyclic AMP, cyclic GMP, GTP, CoA, FAD, NAD^>+) are key regulators of metabolism and cells and the body as a whole.

A decrease in the concentration of ATP and NAD(P)H leads to a decrease in the concentration, including nucleotides – substrates for the synthesis of nucleic acids (RNA and DNA): GTP, CTP, UTP, deoxy-ATP, deoxy-GTP, deoxy-CTP and deoxy-TTP.

There is no more toxic and operatively acting pathogenic factor than oxygen deficiency in the body due to the presence of such a large number of enhancers and distributors of its pathogenic effect on cell metabolism.

The whole history of oxygen life takes place under the sign of the economical consumption of always scarce oxygen, at all levels of the organization.

An important mechanism for this saving is the creation of oxygen reserves, especially in intensively functioning tissues and organs. The central nervous system, which is the most powerful and most intensive consumer of oxygen (per gram of mass per unit of time) as the main energy carrier, uses glucose, a semi-oxidized product containing its own oxygen. Glial cells that perform auxiliary functions contain glycogen, which also allows them to conserve oxygen, which is necessary for the functioning of neurons. I will dwell on other mechanisms for saving oxygen later.

I will list some of the main primary consequences of hypoxia for cells and the body as a whole.

1. Activation of an energy-dependent, regulated process of programmed cell death – apoptosis, which is safe for the surrounding tissues and for the organism as a whole, as a result of external influences. Apoptosis is not self-destruction of a cell, but it killing by external factors, in the extreme case, apoptosis can be considered as forcing cells to commit suicide by external factors: – the main physiological – cortisol (circadian rhythm), which with age increasingly becomes pathological (age-dependent growth basal level of cortisol and distress), and the main pathological one – hypoxia.