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.Telomery – kintsevi dilianky khromosom – tse zakhysni «kovpachky», iaki zabezpechuiut' ïkhniu stabil'nist'. Vkorochennia telomer ie odniieiu z naĭvazhlyvishykh biologichnykh oznak starinnia, prychetne do protsesiv starinnia klityn i zadiiane u mekhanizmakh «mitotychnogo godynnyka». Poshkodzhennia telomer vil'nymy radykalamy ie odnym iz vidomykh mekhanizmiv vplyvu radiatsiï na protsesy starinnia. A okysliuval'nyĭ stres maie toksychnu diiu na dovzhynu telomer.Zbil'shennia vil'nykh radykaliv vidbuvaiet'sia pid diieiu iak ionizuiuchogo, tak i neionizuiuchogo vyprominiuvannia, khocha antyoksydantni mekhanizmy neridko zdatni neĭtralizuvaty shkidlyvi vil'ni radykaly. Neionizuiuchi ta ionizuiuchi vyprominiuvannia navit' u malykh dozakh sprychyniaiut' aktyvatsiiu antyoksydantnykh system, odnak pry vplyvi na organizm oprominennia u vysokiĭ dozi abo protiagom tryvalogo chasu, chy to iakshcho v organizmi vidbuvaiut'sia patologichni protsesy z okysliuval'nym stresom, poshkodzhennia klityny staiut' bil'sh vyraznymy, a protsesy starinnia pryskoriuiut'sia. Pidtrymannia dovzhyny telomer i normal'noï shvydkosti starinnia ie vazhlyvymy dlia stanu zdorov’ia. V ogliadi obgovoriuiet'sia rol' ionizuiuchogo ta neionizuiuchogo vyprominiuvannia u protsesakh klitynnogo starinnia, zokrema – u skorochenni dovzhyny telomer.