PUBLICATION

Impact of Low-level Ionizing Radiation on Cell Death During Zebrafish Embryonic Development

Authors
Barrett, C., Hellickson, I., Ben-Avi, L., Lamb, D., Krahenbuhl, M., Cerveny, K.L.
ID
ZDB-PUB-180227-10
Date
2018
Source
Health physics   114: 421-428 (Journal)
Registered Authors
Cerveny, Kara
Keywords
none
MeSH Terms
  • Animals
  • Apoptosis/radiation effects*
  • DNA Damage/radiation effects
  • Dose-Response Relationship, Radiation
  • Embryo, Nonmammalian/pathology*
  • Embryo, Nonmammalian/radiation effects
  • Embryonic Development/radiation effects*
  • Gamma Rays
  • Radiation Exposure
  • Zebrafish/embryology*
PubMed
29481533 Full text @ Health Phys
Abstract
Ionizing radiation (IR) has been linked to multiple types of cellular responses, but its effects on developing organisms are still poorly understood. The authors investigated whether zebrafish embryos exhibit differential responses relative to IR dose and developmental age at time of exposure. Early-stage zebrafish embryos were exposed to different levels of gamma radiation and then, at varying points after irradiation, assayed for morphological defects and levels of cell death. To quantify in vivo cellular responses to low-dose IR exposure and explore how tissue-specific cell functions affect radiation response, apoptotic cells were counted in three regions: the tail, urogenital papilla, and left eye. The authors found that increased gamma radiation doses correlated with increased levels of apoptosis in the developing tail and eye, whereas cells of the urogenital papilla appeared to undergo apoptosis independently of radiation dose. This suggests that the linear-no-threshold model may not be appropriate in all contexts. Grouping embryos by age at IR exposure revealed that gamma radiation exposure resulted in higher levels of apoptosis in embryos irradiated at 2 d post fertilization (dpf), suggesting a radiosensitive stage of development. Moreover, levels of apoptosis were statistically influenced by days grown after irradiation, with embryos fixed at later stages showing more dramatic apoptotic responses to radiation exposure. This latency to effect suggests potential competition between DNA repair and apoptosis pathways, which may lead to the accumulation of apoptotic cells only after an initial lag period.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping