title: X-irradiation induces cell death in fetal fibroblasts.
abstract: The impact of ionizing radiation on developing organisms has been widely             studied for risk assessment purposes. Even though efforts have been made to decrease             received doses to as low as reasonably achievable, the possibility of accidental             exposure has to be considered as well. Mammalian gestation is usually divided             into three periods. Radiation exposure during the 'pre-implantation period' may             essentially result in embryonic mortality while exposure during the 'organogenesis             period' may characteristically lead to malformations. In humans, the 'fetal period'             is one of particular sensitivity to radiation induction of mental retardation,             especially if the exposure occurs between weeks 8-15 of gestation. It is also             admitted that prenatal irradiation may increase the risk of leukemia and childhood             cancer, with an equal risk over the whole pregnancy. The aim of this study was             to investigate the effects of moderate to high doses of X-irradiation on mouse             skin fetal fibroblasts, one of the cell types subjected to the highest dose of             radiation. Exposure of the cells to X-rays led to a rapid and significant increase             in γ-H2AX foci, indicative of high levels of DNA double strand breaks. High doses             (>2 Gy) also led to a pronounced G2-arrest and a decrease in the number of             cells in the S phase, which was followed after 24 h by a decrease in cell survival             and an increase in the level of apoptosis and necrosis. This study shows that             mouse fetal skin fibroblasts are sensitive to high doses of X-irradiation. Furthermore,             we report a better repair for higher doses than lower, which seems to indicate             that little DNA damage is not necessarily repaired immediately. However, more             sensitive approaches are necessary to identify the risk associated with low doses             of radiation.
authors.affiliation: Laboratory of Molecular and Cellular Biology, Institute for Environment,                     Health and Safety, Belgian Nuclear Research Centre, SCK•CEN, Mol, Belgium.
authors.forename: Michaël
authors.initials: M
authors.lastname: Beck
authors.forename: Marjan
authors.initials: M
authors.lastname: Moreels
authors.forename: Paul
authors.initials: P
authors.lastname: Jacquet
authors.forename: Patrick
authors.initials: P
authors.lastname: Van Oostveldt
authors.forename: Winnok H
authors.initials: WH
authors.lastname: De Vos
authors.forename: Sarah
authors.initials: S
authors.lastname: Baatout
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000528:radiation effects*; D002460:Cell Line; D049109:Cell Proliferation / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects*; D053903:DNA Breaks, Double-Stranded / Q000528:radiation effects*; D004249:DNA Damage / Q000528:radiation effects; D004260:DNA Repair / Q000528:radiation effects; D005333:Fetus / Q000528:radiation effects*; D005347:Fibroblasts / Q000528:radiation effects*; D059565:G2 Phase Cell Cycle Checkpoints / Q000528:radiation effects; D006657:Histones / Q000096:biosynthesis / Q000528:radiation effects; D051379:Mice; D009336:Necrosis; D012867:Skin / Q000196:embryology* / Q000528:radiation effects; D014965:X-Rays
chemical_list: D006657:Histones; C475961:gamma-H2AX protein, mouse