EFFECT OF RADIATION ON AGING PROCESSES AND TELOMERE LENGTH.

Telomeres are the ending areas of chromosomes - protective «caps» that ensure the stability of chromosomes. Telomere shortening is one of the most important biological signs of aging and is involved in cellular aging and the «mitotic clock» mechanism. One of the known mechanisms of the impact of radiation on the aging process is damage to telomeres by free radicals. Oxidative stress has a toxic effect on telomere length. The increase in free radicals occurs under the action of both ionizing and nonionizing radiation, although antioxidant mechanisms are often able to neutralize harmful free radicals. Low doses of nonionizing and ionizing radiation even cause the activation of antioxidant systems, however, when the body is exposed to radiation at a high dose or for a long time, or if pathological processes with oxidative stress occur in the body, damage to cells becomes more noticeable, and aging processes accelerate. Maintaining telomere length and a normal rate of aging is important for health. In this review, we want to discuss the role of ionizing and nonionizing radiation in cellular aging, in particular, in the shortening of telomere length.