Detection of clustered DNA damage in neuronal cells induced by ionizing radiation with different physical characteristics

Abstract

Ionizing radiation with different physical characteristics induces a wide spectrum of DNA damage. The structural DNA damage, such as single-strand breaks (SSB), double-strand breaks (DSB) and AP sites (abasic sites missing either a pyrimidine or purine nucleotide), as well as cluster damage, which are the set of all these damage, is the main factor which could lead to the formation of various mutations, chromosome aberrations, and further cell death. In this regard, research of DNA damage induction and repair under the action of ionizing radiation is the most important goal in radiation genetics, radiotherapy and space radiobiology. It is commonly known that a substantial amount of enzymes implicated in the identification, localization and damage repair formed during the action of various physical, chemical or biological factors is involved in the repair process. The use of DNA repair enzymes involved in the base excision repair, such as DNA endonuclease III (Endo III) and formamidopyrimidine glycosylase (Fpg) expanded the spectrum of experimentally-detectable clustered DNA damage. The induction and repair regularities of DNA damage (DSB, SSB, AP sites) in mammalian neuronal cells induced by ionizing radiation with different physical characteristics were investigated with the Comet Assay modifications (neutral, alkaline, enzymatic).