title: Clustered DNA damage on subcellular level: effect of scavengers.
abstract: Clustered DNA damages are induced by ionizing radiation, particularly of high linear energy transfer (LET). Compared to isolated DNA damage sites, their biological effects can be more severe. We investigated a clustered DNA damage induced by high LET radiation (C 290 MeV u(-1) and Fe 500 MeV u(-1)) in pBR322 plasmid DNA. The plasmid is dissolved in pure water or in aqueous solution of one of the three scavengers (coumarin-3-carboxylic acid, dimethylsulfoxide, and glycylglycine). The yield of double strand breaks (DSB) induced in the DNA plasmid-scavenger system by heavy ion radiation was found to decrease with increasing scavenging capacity due to reaction with hydroxyl radical, linearly with high correlation coefficients. The yield of non-DSB clusters was found to occur twice as much as the DSB. Their decrease with increasing scavenging capacity had lower linear correlation coefficients. This indicates that the yield of non-DSB clusters depends on more factors, which are likely connected to the chemical properties of individual scavengers.
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, Fysikgrården 4, 412 96, Göteborg, Sweden, brabcova.katerina@gmail.com.
authors.forename: Kateřina
authors.initials: K
authors.lastname: Pachnerová Brabcová
authors.forename: Lembit
authors.initials: L
authors.lastname: Sihver
authors.forename: Nakahiro
authors.initials: N
authors.lastname: Yasuda
authors.forename: Youichirou
authors.initials: Y
authors.lastname: Matuo
authors.forename: Václav
authors.initials: V
authors.lastname: Stěpán
authors.forename: Marie
authors.initials: M
authors.lastname: Davídková
mesh_terms: D053903:DNA Breaks, Double-Stranded / Q000187:drug effects* / Q000528:radiation effects*; D053904:DNA Breaks, Single-Stranded / Q000187:drug effects* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D016166:Free Radical Scavengers / Q000494:pharmacology*; D020450:Heavy Ions / Q000009:adverse effects; D042541:Intracellular Space / Q000187:drug effects / Q000378:metabolism* / Q000528:radiation effects; D010957:Plasmids / Q000235:genetics
chemical_list: D016166:Free Radical Scavengers